Nov. 10, 1970 J. E. ANTES ET ELECTRICAL CONNECTOR 6 Sheets-Sheet 1 Filed Feb. 12, 1968 Nov. 10, 1970 ANTES ETAL ELECTRICAL comwcwon 6 Sheets-SheetZ Filed Feb. 12, 1968 J. a. ANTES T AL Nov. 10, 1970 6 Sheets-Sheet 3 Nov. 10, 1970 ANTES ETAL ELECTRICAL CONNECTOR 6 Sheds-Sheet 4 Filed Feb. 1,2, 1968 NW. 10, 1970 J, E, Es ETAL 3,39,@73
ELECTRI CAL CONNECTOR "F2106 Feb. 12, 1968 6Sheets-Sheet 5 Nov. 10, 1970 J. E. ANTES ETAL ELECTRICAL CONNECTOR 6 Sheets-Sheet 6 Filed 'Fb. 12, 1968 3,539,973 Patented Nov. 10, 1970 3,539373 ELECTRICAL CONNECTOR Jack E. Antes, Lakewood, and Jackie Wright, Costa Mesa, Calif., assignors to Hughes Aircraft Company, Culver City, Calif., a corporation of Delaware Filed Feb. 12, 1968, Ser. No. 704,867 Int. Cl. H011 13/34 U.S. Cl. 339143 2 Claims ABSTRACT OF THE DISCLOSURE A connector providing radio frequency shielding and preventing propagation of unwanted noise into electronic equipment. In one embodiment two mating connector sections are oppositely mountable on the apertured equipment frame. One section comprises a connector body; a solid gasket of elastomer impregnated with conductive material, or a laminated gasket of alternate layers of such material and metal, a surrounding flanged gasket constricting radio frequency interference shield having a shield aperture; a filter contact support and isolation block which covers the shield aperture and has a metal surfaced boss thicker than the shield aperture depth inserted through the aperture; and tension connecting jackscrew means. The block member, gasket, and body have transverse apertures to removably retain filter pin or socket contacts. Each filter contact comprises a tubular pi filter having an external capacitor plate interference fitted in a gasket aperture. The shield and gasket are of structure, configuration, and material so that pressure on the gasket of the retained filter contacts and pressure on the gasket of the secured shield substantially grounds certain unwanted high frequency noise through the gasket to the shield and substantial percentages of some frequencies representing unwanted noise are reflected. Another embodiment comprises a filter section connected between pin and socket connector sections and having a tubular shield configured to connect to frames of various thicknesses.
BACKGROUND OF THE INVENTION Field of the invention The present invention relates to improved multicontact electrical connectors. More particularly it relates to such connectors wherein Without sacrifice of number and significant size of connector contacts and pins, a substantial portion of stray or extraneous unwanted incoming radio frequency signals energy is reflected back or such energy is bypassed to be reduced to a level where the electrical noise or interference will not prevent receiving usable electronic signals.
Description of the prior art Connectors wherein multiple grounding connections are provided are described in U.S. Patent No. 3,231,843 of J. E. Antes et al., for Grounding Connector, issued Jan. 25, 1966. Multicontact connectors which incorporate a similar jackscrew means for securing and indexing the connector bodies containing a plurality of closely spaced contact pins and sockets are described in U.S. Patent No. 32% 1,761 of N. L. Moulin, for Connector Securing Device, issued Oct. 25, 1966 and assigned to the assignee of the present invention. The disclosure of the Moulin Pat. 3,281,761, is incorporated by reference in the present invention. While the connector of the Moulin Pat. 3,281,761 is a very desirable connector for many purposes it does not provide the means of the present invention which, without decreasing the space alloted for contact pin and socket elements, incorporates filter, shielding, isolation, and grounding means whereby unwanted noise or signals, particularly at high frequencies are bypassed to ground or reflected back while allowing the desired electrical signal voltages to pass through the contact pins and sockets of the connector.
Prior art devices attempted to solve the problems by less advantageous or unsuitable means by employing electrical filter networks made up of discrete components, i.e., capacitors, resistors, and/or inductors and miniaturized versions of these, or by providing larger connectors and inserting separate filters in the additional space provided. Also, such prior art devices do not provide removable enclosures with removable contact pins and sockets and do not effectively reflect back or ground out the unwanted signals. They do not provide shielding means to substantially totally isolate the structure from unwanted radio frequency energy. Such prior art devices do not solve the problem where a removable type contact that can be closely spaced together is needed. They do require additional space-consuming and/or costly radio frequency (RF) gasketing devices to minimize RF leakage paths. They do not provide for required inter changeability of parts and do not provide for ready adaption to external equipments having frames of different thicknesses without substantial loss of shielding effectiveness.
The present invention overcomes these and other disadvantages of prior art devices. The invention provides a connector which is capable of efiicient overall shielding effectiveness. It provides removable connector contact pins and sockets and removable filter connector contact pins and sockets in conjunction with means to reflect back to effect attenuation of stray or extraneous RF energy to a level where the signal noise or interference will not prevent receiving a usable electrical signal. The invention further solves problems where interconnection leads traversing a shield wall must be coupled in order to prevent the conduction of RF energy into and out of the shielded enclosure via the leads. The invention further provides a filter that is usable in existing available space in a connector without changing the contact pin density and without losing the environmental shield, further provides RF shielding of the opening required for a connector which is mounted in a grounded shield wall, and provides a resilient deformable conductive means and a support and isolation means which in conjunction provides reflecting back of certain unwanted noise frequencies and provides a conductive path to certain noise frequencies between the filter and the shield.
T bus the invention provides a device wherein available space in a connector is utilized without loss in contact number density, the same connector body may be used Without changes being required to insert selectively either filter pin or socket contact elements or alternatively regular (without a filter) pin or socket contact elements and provides shielding and a grounding means which effects both shielding of the connector and ground and/or reflection back of unwanted frequencies in the signals coming through the contact elements of the connector. The invention further provides an RF noise grounding means which eliminates Weight increase normally expected by the addition of filtering components and wherein failure due to metal fatigue is minimized. The invention also provides a device which is adaptable to electrical equipment of various frame thicknesses and wherein optionally filter and ordinary connector contacts can be supplied with a reduced number of different parts.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a connector adapted to mate with a wide variety of electrical equipment, which, without requirement for additional space in the connector body, provides substantially total shielding, reflects substantial amounts of noise signals of certain frequencies, and filters and grounds substantial amounts of noise signals of certain ranges of frequencies entering into the leads traversing the shield enclosure.
Another object of the present invention is to provide a connector with a shield wall enclosure structure and interconnection lead contact filter elements, pins and sockets in the connection means which traverse the shield wall to provide decoupling and to prevent the conduction of certain radio frequency energy through the shielded enclosure wall via the leads.
Still another object of the present invention is to provide a connector incorporating a filter contact means, an RF shield, and grounding means that is structured to fit within existing available space taken up by the connector without changing the contact socket or pin density and without losing the environmental shielding and in addition which will provide RF shielding of the openings required for the connectors when mounted in a shield wall.
Another object of the present invention is to provide a connector with alternatively insertable substantially similarly dimensioned and configured filter and regular contacts, wherein already available space in the connector is utilized without loss in contact number density, wherein a grounding means is provided which also shield the opening caused by the presence of the connector body, and also reflects back to the connector certain unwanted signals, where substantially no weight increase is necessitated by the additional filter, grounding, reflecting and shielding functions and metal fatigue is substantially avoided.
Another object of the invention is to provide in a connector body a means to ground the capacitor(s) of a filter contact socket or pin to a reference ground which is the wall of a shielding hood enclosure secured to a frame wherein a deformable conductive member with preformed undersized apertures interferingly contacts an outside capacitor plate of each filter pin or socket in the connector sections and wherein the deformable conductive member which may have a plurality of conductive layers in parallel to lower the resistance path is electrically contacted by a hood which extends around the periphery of the deformable member and is dimensioned to compress the deformable member transversely.
Yet another object of the present invention is to pro vide a connector incorporating means to provide RF shielding to filter unwanted noise at certain frequencies, to reflect back unwanted noise at certain frequencies, laminated deformable means to form an improved conductive grounding path to the RF shield for the filter noise and to aid in the unwanted noise reflecting and a support and isolation block sized to exert pressure on the deformable means and having a metal layer to enhance the reflection of or grounding of unwanted frequencies.
Still another object of the present invention is to provide a filter contacts connector section and mating pin and socket contact connector sections wherein selectively the filter contact connector section may be incorporated or not incorporated in combination between a pin and a socket contact connector section and wherein is provided a conductive radio frequency interference shield disposed in protective and grounding relationship to the filter contact connector section and a mating connector section and which is configured to be secured to frames of varying thicknesses.
According to the present invention there is provided an electrical connector particularly for connecting into and out of electrical equipment while providing shielding and minimizing or reducing of noise passage therethrough comprising; superimposed connector body and deformable conductive gasket members each having a plurality of closely spaced, transverse connector contact receiving apertures, the gasket and body apertures being respectively aligned, a grounding and radio frequency interference shielding hood surrounding the gasket and body, means which may in a first embodiment comprise a flange for the hood and a support and isolation block having a boss provided with a conductive face layer received in close fitting relationship into the can aperture with the boss face bearing upon the face of the deformable gasket, and in a second embodiment may comprise a surrounding radio frequency shielding enclosure around the gasket and the connector body which is configured to combine with frames or chassis of electrical equipment which frames may be of diflering thicknesses, means to connect the hood means, and gasket under tension to the frame to provide a shielding enclosure and wherein the gasket is compressed by, in the first embodiment connector filter contact pins or sockets and in the second embodiment connector pins, sockets, and filter interconnector contacts removably inserted in the aligned apertures, the connector body being provided with apertures of greater than con tact diameter to receive contact inserting and removing tools therebetween, the deformable gasket being provided with critically undersized holes for contacting the filter, for example, contacting a capacitor plate of each filter of the connector contacts when inserted into the aligned apertures in the connector (or interconnector) body and in the gasket. The conductive gasket which may comprise an elastomer or rubber material impregnated with conductive particles or alternate laminations of such impregnated material and metal foil providing reflection of some unwanted frequencies and parallel paths for lowered reresistance, prevents unwanted inductance and therefore shared coupling and cross-talk by grounding unwanted signals to the hood. The radio frequency interference shielding hood provides both better electrical connection and mechanical rigidity due to its flanged and large contact area configuration. The gasket material in the first embodiment is subject to both transverse hood compression against the top surface and lateral and longitudinal compression around the upper edges of the top surface and in the second embodiment to annular shield compression and in both embodiments to lateral compression because of the aperture diameter being critically smaller than the contact filter diameter. In the first embodiment the top compression at the gaske edges is provided by flange securing means inasmuch as the depth from the inner hood top face is less than the connector body and attached gasket thickness. The central gasket, connector body, and block means may be secured together and connector section polarization and other structural alignment obtained in the first embodiment by jackscrew and spanner nut means. The connector contact pins and sockets may be held in place by an encircling outwardly flaring spring member and the invention provides for the required room for tool entry to compress flaring portions of the spring for disassembly of the contact. This is provided by the above-described space due to the connector body aperture diameter being made larger than the connector filter contact outside diameter provided by the in vention. The gasket interference fitting size apertures of the invention into which the contacts are inserted pro vides good electrical connection of the filter to the conductive gasket and thus to ground, providing yieldable but firm support for the otherwise loosely fitting fragile pin and prevents RF energy from leaking through along the aligned apertures. The invention further provides that the gasket be manufactured by a process to render it satisfactorily corrosion resistant, that the gasket or in the laminated case its elastomer or rubber layers contain an amount of embedded conductive material and be of material, softness, shape and structure for proper compressibility to provide the necessary conductivity at the frequencies of energy required to be grounded.
The foregoing and other objects and attendant advantages, features, and uses of the devices embodying th invention will become more apparent to those skilled in the art as a more detailed description proceeds when considered in conjunction with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view illustrative of a first preferred embodiment of the invention showing the elements of a first connector section and the body of a second connector section in position to be assembled and mounted to the frame of a unit of electrical equipment, for clarity illustrating only one filter connector socket contact in position to be fitted into the aligned apertures of a block, deformable conductive gasket, and connector body and illustrating the radio frequency interference shielding enclosure, the shielding enclosure flange and securing means and the jackscrew aligning and securing means of the first preferred embodiment;
FIG. 2 is an enlarged view of the filter contact socket element of FIG. 1;
FIG. 3 is a schematic diagram illustrating the electrical equivalent of the filter and grounding provided in the embodiment of FIGS. 1 and 2;
FIG. 4 is a side view of the first connector section of FIG. 1 in assembled relationship and with portions broken away to present sectional views of the elements to facilitate the explanation of the invention;
FIG. 5 is a side view partly in section of a male connector section having elements similar to those of the illustrative embodiment of FIGS. 14 but showing a modified connector body and a seal member to render the section more suitable for retaining the connector filter contact pin instead of the filter contact socket;
FIG. 6 is a second preferred embodiment of the combination of the invention with portions shown in crosssection to more clearly show certain elements and illustrating an embodiment comprising an a igned substantially tubular socket section, pin section, and optionally employed filter connector section and an annular encircling shield configured to connect to frames of different thicknesses and wherein a deformable conductive gasket is constricted by internal aperture contained filter contact elements and externally by the annularly encircling shield;
FIG. 7 is a second embodiment of a filter contact section interchangeable with the filter contact section of the embodiment of FIG. 6 and wherein the modified filter contact section is readily disassembled;
FIG. 8 is an electrical schematic diagram to facilitate explanation of the adverse effect on filter effectiveness of poor grounding of a filter capacitor plate through the gasket to the shielding enclosure which the present invention minimizes;
FIG. 9 is an electrical schematic diagram to facilitate function of the invention structure to minimize the unwanted coupling effect caused by sharing a common resistor which occurs when the path between two adjacent filter connector contacts is insufficiently conductive; and
FIG. 10 is a cross-sectional view of a second preferred illustrative embodiment laminated deformable conductive gasket which may be employed in the preferred illustrative embodiment connector section of FIGS. l5 and which alternatively to a solid gasket comprises alternate thin metallic foil or coating and thin deformable rubber, synthetic rubber or elastomer layers.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The primary power leads into and out of any equipment enclosure that connect to a power bus must be filtered. Even if not economical, necessity for conserving space may dictate using connectors into and out of the enclosure. It is desirable that the filters be an integral part of the input connector mechanism. Voltage supply leads entering or leaving a module or subchassis enclosure, for example where a local oscillator, mixer, modulator, or RF amplifier and high level RF energy circuits are concerned, must be also adequately filtered to minimize the transfer of RF energy from inside the module or subchassis enclosure to other critical circuits external to the subchassis. The filtering requirement applies to all leads including B+ leads, high voltage leads, filament leads and other leads which do not intentionally carry RF signals as well as the signal leads.
In the type of connector to which the invention relates closely spaced connector contact sockets and closely spaced contact pins are required. The present invention provides for this requirement by effectively utilizing integral ferrite loaded filter contact sockets or pins in combination with a critical cooperating retaining, sealing, and grounding gasket. The filter must have the best possible attenuation over a specified frequency range. Filtering only in the primary leads cannot be relied upon. As will become apparent in the light of description hereinbelow, the small bulkhead type feed-through filters along with other decoupling means of the invention and its improved grounding means minimizes the transfer of RF energy from the inside of a chassis enclosure to other critical circuits external to the chassis. The bulkhead mounted filter must be well grounded to preserve the shielding integrity of the enclosure. The invention combination incorporates feed-through filters with the grounding means which is critical to provide attenuation of a wide range of higher frequencies which should not be passed through the connector. The combination provides the maximum isolation between input and output of the filter and a minimum inductance path to ground.
Refer to FIGS. 1 and 4. The connector (not numbered) comprises two mating connector sections (not numbered) which are interfitted in mating relationship on the outside and inside of a frame or chassis 26. Frame 26 encloses electronic apparatus (not shown). The electronic apparatus may be computer or communications equipment, for example. Frame 26 is adapted to provide the mounting for the connector by machining or otherwise forming therein a connector body retaining aperture 54 and a pair of bolt, screw, or other mounting hardware retaining apertures 510. In the FIGS. 1 and 4 illustrative embodiment, apertures 51c are threaded to receivebolts 27 which are provided. Optionally, apertures 510 may be bored without threads and nuts may be provided to secure thebolts 27.
Aconnector body 21 molded or otherwise formed of electrical insulating material is provided.Connector body 21 is formed of three generally rectangular parallelepiped shaped sections, a protruding boss section 21a, an intermediate interfitting boss section 21b and a body section 210.
The body section 210 is the longest section, the intermediate boss section 21b is shorter in length but of the same width as thebody section 21c and the protruding boss section 21a is shorter and narrower than the other two sections 21a and 210.Protruding boss section 21c extends through aperture 54. Intermediate boss section 21b interfits into to fill rectangular aperture 54 in mountingframe 2 6. Mounting frame 26 is at electrical ground potential.
A deformableconductive gasket 22 of material and structure to provide a low impedance path to electrical ground potential is provided.
Gasket 22 is also of generally rectangular parallelepiped shape, of the same cross-sectional rectangular dimensions asbody section 21. One face ofgasket 22 may be cemented to the face of body section 210 ofconnector body 21. Theconductive gasket 22 is formed of a yieldable or compressible and relatively flexible rubber or elastomer material which is very conductive to AC. noise of certain frequencies under compression or is formed of alternate layers of deformable material and of metal coating or foil (see FIG. 10). When properly configuredgasket 22 reflects an adequate proportion of certain noise frequency energy.
Ingasket 22 is molded or otherwise formed a plurality of closely spaced relatively small criticallysized apertures 37 to removably retainfilter connector sockets 29 or pins 70 (see FIG. or ordinary connector contact pins or sockets which carry the signal and power voltage input and output into and out of the electrical apparatus for which the inventive connector is provided. Thefilter contact sockets 29 or pins 70 each comprise atubular filter 59 or 97 which are provided and disposed along a portion of the contact length. The diameter ofapertures 37 is critical with relation to the diameter of the pin or the socket portion contained therein. Theapertures 37 diameter is lesser than thecontact socket 29 orpin 70 diameters to the extent that the tubular filters of thecontact sockets 29 or pins 70 fit into theapertures 37 in an interference fit. However, the difference must not be so great as to cause misalignment of theapertures 37. FIG. 1 illustrates a single filterconnector contact socket 29 in position to be inserted into anaperture 37. Thegasket 22 material parameters as well as the sizing of its apertures are critical to be suitable for connector use as will be explained hereinafter in greater detail. In the first preferred illustrative embodiment configuration (FIGS. 1, 4 and 5) the gasket is made of rubber or elastomer material impregnated with conductive material and in a second preferred illustrative embodiment (FIG. alternate layers of such rubber or elastomer material (impregnated with nonconductive material) and of metal foil (or a metal coating) are provided. Unwanted frequency noise is bypassed through thefilter 59 of the filterconnector contact socket 29 orpin 70 to theconductive gasket 22. It is critical also thatconductive gasket 22 be of low impedance to provide a good connection through it to ground and that it have certain other characteristics to aid in reflecting certain noise frequencies out of the equipment. The structure and material ofgasket 22 required to perform these functions in the connector of the invention is explained in detail hereinafter to facilitate clarity of description in the light of the first following further explanation of the units and elements of the connector.
A hollow rectangular parallelepiped shaped radio frequency interference (RFI) shielding enclosure or shield 23 having an outwardlyflanged portion 35 is provided.Shield 23 is formed of metal.
The radio frequency interference (RFI)shield 23 is open on the flanged side and is hollow to define together with the mounting frame 26, a generally rectangular parallelepiped configuration chamber (not numbered) sized and shaped with relation to the size and shape ofconnector body 21c and theconductive material gasket 22, such that body 210 andgasket 22 are enclosed in the chamber byshield 23 and thegasket 22 is compressed (transversely) between the underside of the shield upper surface 36 and the adjoining face of the body section 210 of theconnector body 21.
As shown in phantom in FIG. 1 theflange 35 of theshield 23 bears upon bearing portion 34 of mounting frame 26. Through the surface 36 (opposite flange 35) ofRFI shield 23 is machined or otherwise formed a rectangular shaped aperture 20.
A filter support andisolation block 24 is provided.Block 24 comprises two substantially rectangular parallelepiped shaped portions, a block body 50 and a reduced length and width block boss 31.Block 24 is formed of nonconductive material. The rectangular boss 31 ofblock 24 is seated in the rectangular aperture ofRFI shielding enclosure 23. The block body 50 ofisolation block 24 rests upon the surface 36 of the shieldingenclosure 23. The surface of boss 31 is metal coated, or provided with a separate attached foil, or otherwise provided with ametal layer 30. Boss 31 and metal layer are of thickness greater than the depth of aperture 20 so that a deforming pressure is exerted upongasket 22 to render it more conductive in a manner to be described. Deformableconductive gasket 22 is molded, machined, or otherwise provided with a plurality of closely spacedapertures 37. Filterconnector contact sockets 29 are provided and fitted intoapertures 37, therespective aperture 37 and socket diameters being such as to provide an interference fit ofsockets 29 inapertures 37.
Connector body 21 is provided withapertures 37a and connectorcontact support block 24 is provided with apertures 37]), therespective apertures 37, 37a and 37b being aligned for removable insertion of filterconnector contact sockets 29 as shown in FIG. 4-. Optionally, filter connector contact pins (see FIG. 5) or regular contact pins or sockets could be removably inserted in respective aligned trios ofapertures 37, 37a and 37b. The fit of the contact pins 70 or regular sockets or pins inaperture 37 is also an interference fit. Theapertures 37, 37a and 37!) cover an area bounded by shield aperture 20 to enable free contact insertion and removal. A- pair of threadedbolts 27 and pairs of respectively aligned RFI shieldedenclosure retaining apertures 51,gasket retaining apertures 51a and connector body retaining apertures 5112 are provided.Bolts 27 are threaded throughrespective apertures 51, 51a and 51b and threadedly engaged in mounting hardware retaining apertures 51c in frame 26 to retain theshield 23, the deformableconductive gasket 22, and theconnector body 21 upon the mounting frame 26 for shielding of thefilter connectors 29 and reflection or grounding of unwanted signals in a manner to be described. A connector polarizing and securing (or jackscrew)device 25 similar to that described in the aforementioned US. Pat. No. 3,281,761 of Moulin is provided. The connector polarizing and securingdevice 25 comprises a threadedshaft 32 which terminates in a turned or otherwise formedjackscrew boss 32a at one end and at the other end terminates in an aligning and securingboss 60. Aligning and securing boss 61) comprises a plurality of separatedkeys 52 the separations of which definenotches 53. Machined, molded or otherwise provided in connectorcontact support block 24, deformableconductive gasket 22, andconnector body 21 are respective blockcentral aperture 33, conductive gasketcentral aperture 33a and connector body central aperture 33b.Apertures 33, 33a and 33b are aligned and of diameter to removably retain theconnector securing device 25. Thecentral aperture 33 of the connectorcontact support block 24 is terminated with a block counterbore to form a spannernut stop shelf 81. The threadedshaft portion 32 and theboss 32a of connector polarizing and securingboss 25 protrudes through thecentral aperture 33.Spanner nut 28 fits intocounterbore 33, and is threadedly engaged upon the threadedshaft portion 32 of connector polarizing and securingdevice 25 to clamp together the filter connector contact support andisolation block 24, thegasket 22 and theconnector body 21. The assembly is tightened to the required securing stress. Thekeys 52 andnotches 53 are mated with the keys and notches of the connector body aligning and securing device (not shown) on the opposite side of the frame 26 to provide proper polarizing (aligning of the respective pins and sockets to be connected to each other).
A mating connector body assembly comprising additional units such as securingdevice 25,connector body 21,gasket 22,shield 23,isolation block 24,nut 28 and mountingscrews 27, is provided on the opposite side of the mounting frame 26 to complete the connection of signal and power carrying leads into and out of the electrical apparatus. The connector bodies on opposite mounting frame sides are of course complements, for example sincebody 21 of the first illustrative embodiment has boss 21a, the opposite frame side body provided is connector body 57 (see FIGS. 1 and 5) which is formed to have hollow connector body boss receptaclepin protecting portion 56. Thecontact sockets 29 or contact pins 70 are inserted optionally in either the connector body 21 (shown inside but optionally outside the frame) or the connector body 57 (shown outside but optionally inside the frame) and the mating connector contact pin or socket is secured in themating connector body 21 or 57 (shown outside but optionally inside the frame) to provide a complete through connection. Theconnector body 57 with theboss receptacle 56 is more suitable to protect thepins 70 and although interchangeability is contemplated usually this connector body will be utilized forcontact pin 70 insertion and theconnector body 21 will be utilized forcontact socket 29 insertion. Usually, also, only one, either theconnector contact pin 70 or theconnector contact socket 29 is a filter connector contact (provided with a filter) since attenuation or reflection may be provided at either end. Optionally, also, a regular connector (see FIG. 1) which omits theconductive material gasket 22 may be provided at one or the other side of the frame 26 since filtering need occur at only one point. Although any arrangement can be made, for convenience, usually all thecontact sockets 29 are inserted in one of the connector sections and the contact pins 70 in the opposite side connector section. Because of the width of theboss receptacle 56 and boss 21a which fits therein, the flanges (not numbered) of theconnector body 57 are spaced from the side of frame 26 opposite the surface 34 side.
Refer again to FIG. 4 in conjunction with FIG. 1.
The basic elements of one of the connector sections may be assembled as follows. Theconductive gasket 22 is cemented to the face of the body section 210 of theconnector body 21. The connector polarizing and securingdevice 25 is then inserted into the cementedassembly 21 and 22. TheRFI shield 23 is then slipped over the cemented assembly. The filter connector contact Support andisolation block 24 is assembled into place so that blockcentral aperture 33 fits over threadedshaft portion 32 of connector polarizing and securingdevice 25 and block boss 31 includingmetal layer 30 ofsupport block 24 fits intorectangular aperture 24 ofRFI shield 23, preventing rotation ofblock 24 with relation to the assembly.Spanner nut 28 is then secured to threadedshaft 32, completing the connector section assembly. Since the boss 31 (with its metal layer 30) is thicker than the depth of aperture ofshield 23, pressure is applied transversely to deformableconductive gasket 22 enhancing its conductivity as will be further explained. The mechanical advantage of jackscrew for causing a strong connection is achieved without the corresponding disadvantage that unwanted signal bypass occurs through the jackscrew. Theaperture 33a ofconductive gasket 22 is sized for interference fit therein of connector polarizing and securing (or jackscrew)device 25. The metal layer as of boss 31 and theconductive gasket 22 form parallel, and therefore by ohms law applied to parallel resistors, 1/ =1/ +1/ 2, a lower resistance grounding path, from the jackscrew 25 to theRFI shield 23 to bypass certain unwanted signals passing through theblock 24 supported end of thejackscrew 25. Also, as will be explained, the metal layer 3th enhances reflection back of certain noise frequencies. Thus, in the invention undesired signals which would otherwise have passed through the jackscrew 25 are short circuited to ground or reflected back in addition to unwanted frequencies of thecontact sockets 29 being bypassed to ground or reflected. The assembled connector section is fastened to mounting frame or chassis 26 with the two mounting hardware threadedbolts 27. Upon fasteningbolts 27, a pcripheral electrical contact with the conductive portion (ground potential) surface 34 is provided by theflange 35 ofshield 23. Grounding of unwanted noise energy fre quencies mHz. to 10 gHz., for example) is facilitated by the action of RFI shield upper surface 36 which applies pressure transversely to deformableconductive gasket 22 whenthreade bolts 27 are tightened to draw flange against bearing surface 34 and hence since the depth ofshield 23 from the under surface of top wall 36 is less than the thickness in unsecured state ofgasket 22 plus body section 210, the inside of upper wall 36 is drawn against and applies pressure ongasket 22. A peripheral electrical bond or contact to the ground potential frame surface 34 is assured by the pressure connection on surface 34 ofouter flange 35 of the shielding can 23 and the metal layer 3th ofisolation block 24. Completely peripheral contact touching substantially all point is provided by the shielding enclosure ofcan 23 upper bearing surface 36 which applies pressure on the elastomeric or rubbersolid gasket 22 or layered gasket 82 (FIG. 10) when tightened by the mountingbolts 27. Thegasket 22 or 82 is deformable such that due to the critical dimensions, configuration and securing of elements it hugs the inside of the shielding can 23 and thus assures a completely peripheral contact, that is a level of total ground. Paths of possible RF leakage are minimized or eliminated due to complete shielding by the metallic covering presented by theRFI shielding enclosure 23 and theconductive gasket 22 or 82. The closely spacedapertures 37 within the deformableconductive gasket 22 or 82 are then filled with filterconnector contact sockets 29, or for economy with dummy radio frequency blocking pins (not shown). The dummy pins are formed of brass or other conductive material and are not provided with filters. Alternatively theapertures 37 may be filled with filter connector contact pins 70. The filter contact sockets 29 (or the filter contact pins when inserted) fit within the deformableconductive gasket 22 or 82apertures 37 or 86 with an interference fit. The resultant pressing of the conductive material around theaperture 37 or 86 against thesockets 29 or pins 70 minimize any chance of radio frequency leakage through the groundinggasket 22 or 82 by radio frequency energy propagation down the wire and contact 29 or 70. Since theapertures 37 in rubber or elastomerconductive gasket 22 or layered gasket 82 (FIG. 10) and the dimensions of the contact sockets 29 (or pins 70) are made such that the contact socket filter outside diameter (at the point touching the gasket) is larger than the diameter of the gasket .22 or 82 aperure, an interference fit is provided between the filter contact socket 29 (or the filter contact pin 70) and the gasket material around the aperture. Thus at the point wheresocket 29 orpin 70 is horizontally resting in theconductive gasket 22 or 82 the rubber or elastomer material (and anyintermediate layer 83 or 84) in spread apart by thecontact socket 29 orpin 70 and the gasket 22 (orgasket 82, FIG. 10) material is compressed to render the gasket more conductive.
Refer again to FIGS. 1 and 4. The provision of the hood or RFI shielding can or shield 23 configured so as to provide a total shielding and grounding arrangement and with its flange provides (1) a better electrical connection because of the flat flange portion and (2) added rigidity to prevent thehood 23 from mechanically buckling. The contact around the entire periphery at the base of thehood 23 is important for proper grounding of the high-frequency signals involved. The distance between the base of thehood 23 atflange 35 and the inner bearing top surface underneath surface 36 (not numbered) and of the hood is critical to cause the exact amount of compression which is required against the top surface of thedeformable gasket 22 or 82 and at the same time to insure connection of thehood 23 to the chassis 26. This enhances the good electrical connection adjacent to each of the filter capacitor portions 63, thegasket 22 or 82, and thegrounding hood 23. This feature also causes thegasket 22 or 82 material to be under compression both laterally and vertically which is required in order that adequate gasket to shield surface contact to bypass the signals is obtained. This enables a good electrical ground without otherwise required alteration of the physical parameters of the connector contacts. It also provides filtering out of unwanted frequencies.
The expandable nature of the rubber orelastomer gasket 22 orlayer 84 around the aperture and the interference fit insure that all parts of thegasket 22 or 82 around theaperture 37 and theelectrode 63 or 97 on the filter of thecontact socket 29 orpin 70 are in contact. This also minimizes or eliminates any change of RF leakage through the groundinggasket 22 or 82 by RF energy propagation down thecontact socket 29 orpin 70 and wire (not numbered). When properly compressed theconductive gasket 22 or 82 provides a virtual short circuit some of the noise frequencies desired to be grounded and if made of proper thickness or comprises a metal layer reflects back other noise frequencies. Further since most of the surface portions of thegasket 22 or 82 are contacted by theshield 23 interior or block 24 metal layer upon expansion without space permitted therebetween this insures optimization of the shielding action.
Refer to FIG. 2. FIG. 2 illustrates the first preferred embodiment filterconnector contact socket 29. The filterconnector contact pin 70 of the first preferred embodiment is illustrated in FIG. 5. Thesefilter contact sockets 29 and pins 70 of FIGS. 2 and 4- present modifications of the type of regular contact pins or sockets available in several sizes under Catalog No. M*l6Y16C000, M*20Y20C000 and M*22Y22C000 (adding S to the number if a socket and P if a pin) from the Electronic Products Division of the Hughes Aircraft Company, 500 Superior Ave. Box 1278, Newport Beach, Calif. Tubular contact socketpin receiving portion 67, spring retaining reducedportion 68 and barrel portion 38 are provided. A longitudinal aperture (not shown) is disposed along the central axis ofportions 67, 68 and 38 to receive the aligned pin of the mating connector section. At the other end offilter contact socket 29 is apin crimp barrel 39. A reduced tubular portion 40 is also provided. An aperture adapted to contain a wire lead (22 gauge wire, for example) from a source of electrical power or signal voltage (not shown) is provided and extends along the central axis within thepin crimp barrel 39 and the tubular section 40. An inspection aperture 42 is provided. At assembly, a cylindrical contact spring (not shown) is inserted aroundtubular section 68 for frictional engagement with the contact pin 69 (see FIG. 5) upon insertion through thetubular section 67 ofcontact socket 29. A pair of contact socket larger diameter beveledportions 43 and 44 separate a reduceddiameter socket section 45 on which is fitted a retaining clip 46. A reduced tubular portion 61 which may retain the pin end, is provided. Alternatively, a wire member could be utilized for the reduced portion 61. A plurality of ferrite beads 47 are strung over a reduced tubular section 41 and form an inductor of a tubular shapedpi filter 59. Aceramic tube 62 is prepared by applying two separate coatings 64 to its inner circumference to form the inner plates or inner electrodes 64 of two capacitors C1 and C2 and a single outer coating to form the outer plate or the outer electrode 63 of capacitors C1 and C2 (see FIG. 3). These electrode coatings may be applied by painting on the ceramic tube a silver or gold slurry, fired on or baked at about 1200 to 1400. The gold slurry may comprise a gold and glass mixture. Thetubular pi filter 59 comprises the inductor provided by the ferrite beads 47 and the two capaictors (C1 and C2 of FIG. 3) comprising the common plate formed by the conductive outside electrode 63 of thefilter 59 and the opposite or inner plates comprising the inner tube conductive layers or electrodes 64, the dielectric comprising theceramic tube 62. The electrical configuration is shown in FIG. 3. The resistance of FIG. 3 represents that of the inductor at the frequencies of RF energy considered in the path laterally through the beads 47. The opposing electrode 63 shown in schematic FIG. 3 as two connected together and grounded electrodes is obtained by painting the entire coating over the surface opposite the conductive coating 64. The inner conductive plates 64, the ceramictubular member 62, and the outer conductive plates 63 thus forms the pair of capacitors Cl and C2 shown in FIG. 3 which together with the inductive reactance or resistance of the ferrite beads forms thepi filter 59. The inductive reactance or the impedance is of the order of 50 ohms at 100 mc. frequency. The capacitors C1 and C2 each are about 750 picofarad capacitors. Thefilter 59 may be of the type obtainable from Eric Technical Products, Inc., Ontario, Canada and is illustrated and described on p. 19 of its catalog under the designation Erie EMI Filters for Use in Connector Assemblies."
As will be described hereinafter, thefilter 59 is grounded through the conductive material filled elastomer or rubber gasket 22 (see FIGS. 1 and 3) or layered gasket 82 (see FIG. 10). The assemblage of the filterconnector contact socket 29 is completed by applying hard solder to retain thefilter tube structure 59 in place. This solder is melted to form solder sections 48 and 49 to make the structure permanent. A dielectric insulatingcoating 56 such as an epoxy paint is provided covering the outside portions of electrode 63, the solder sections 48 and 49, a portion of reduced tubular section 61 and the tubular section 41 adjacent to reduced tubular portion 40. Thus, just the center (gold) coating or plated portion of filter outer electrode 63 is exposed and is connected to theconductive gasket 22 which forms a grounding path from this capacitor plate 63. The painting of thedielectric epoxy 56 on both of the edges permits conduction from the conductive surface 63 into theconductive gasket 22, yet prevents shorting of the high voltage from the pin portion which might otherwise occur because of particles of conductive gasket material or along the conductive material of the gasket. This feature of providing the dielectric along the edges and over the solder portions 48 and 49 thus prevents the signal of voltage from being shorted out.
Refer to FIG. 5. FIG. 5 illustrates a preferred connector section wherein a filter connector contact pin instead of asocket 29 is provided. Thepin 70 structure is similar to that of thecontact socket 29 hereinabove described and thetubular filter 97 provided for thepin 70 is identical. Further description of thepin 70 and itstubular filter 97 details which are the same as or apparent from the socket is therefore not provided. A crimp pin end barrel and acontact pin portion 69 are provided. A wire (not shown) which forms the connection to thebarrel 77 is inserted into the open end of the pin crimp barrel and the assemblage is then crirnped, for example, in four places. The crimp barrel of thepin 70 is placed adjacent to the hard solder as in the above operation for thefilter socket 29. As in the case of thecontact filter 59 the painting material is a silver or gold slurry which is fired on or baked on to form a coating at about 1200 to 1400 The gold slurry comprises a gold and glass mixture comprising about 8090 percent of gold. After the solder is placed adjacent to the ends of the assembly, thecrimp barrel 77 is put on and the unit assembled in an oven at about 361 F. or higher to about 400 F. In this manner, solder flows along thepin contact 70 and makes a good mechanical and electrical connection and the solder also makes a good connection with the inner electrode 64 of theceramic tube filter 59. Optionally, of course, any of several conventional methods of assembly of the wire in thecrimp barrel 77 may be employed, for example, other methods include solder cup assembly wherein the crimp barrel is diagonally cut to provide an open cup configuration for soldering, etc.
As indicated hereinabove the material and parameters ofgasket 22 or 82 are critical. Conductive filler impregnated rubber or elastomer material which has some of the characteristics and parameters for the purposes of the invention is described in aforementioned US. Patent Nos. 3,140,342, 3,194,860, and 3,202,488 and the disclosure of these patents is referenced herein to broadly illustrate the manufacture and composition of material forgasket 22. However, such patented gasket matreial requires critical changes and modifications to be suitable for the present invention. Conductive rubber and other elastomeric ma- 13 terials of the required characteristics may be used as the basic material. Thegasket 22 or 82 must be of suitable hardness conductivity when deformed by the contacts and shield, thickness and configuration, and the apertures must be of proper size for interference fit without misalignment occurring.
Thegasket 22 material may comprise, for example, a synthetic or natural rubber which is made conductive by impregnating therein conductive material. For example, an RTV (room temperature vulcanizing) rubber may be made conductive by impregnating therein silver filler of the greatest possible number to lend conductivity. This may be, for example, from 78 to 92 percent composition of silver filler by weight. Such materials include, for example, rubber materials manufactured by the Ablestick Co. of Gardena, Calif. identified as HPl6l28, RTV 731 Silicone or adhesive silicone rubber MIS13,968; a rubber material sold by the Dow Corning Corp. and identified as RTV3140. Alternatively a synthetic rubber such as Neoprene, Viton, or Hypalon may be utilized. Still further, alternatively, silicone elastomers, urethane elastomers, flexible epoxy or vinyl plastisols may be employed. For connector use, the conductive rubber or other flexible conductive material must be corrosion resistant. Therefore, if a rubber material is selected, the rubber must be noncorrosive, that is, the rubber must give off alcohol when cured rather than acetic acid so as to solve the corrosion problem. This is accomplished by selecting a rubber which can be cured by catalyzing with stannous octoate dibutyl tin dilaurate. Such material when selected must comprise at least 75 percent to 92 percent by Weight of conductive filler such as silver, copper or plated copper spheres to 25 percent of the RTV3140. The so-called conductive elasto'mers and rubbers of the above-mentioned patents and their process are unsuitable. They do not provide the required conductivity and as taught by the invention additional conductive filler should be employed to provide a low resistance path to ground at the proper frequencies and the elastomer rubber or synthetic rubber must be made more conductive by impregnating a larger number and/ or size of metal spheres or other conductive materials. The filler must be sufiicient for the critical conductivity required when thegasket 22 is compressed. The gasket material is not sufiiciently conductive to ground noise frequencies without required compression by the contacts and shield. The degree of hardness of the rubber or elastomer material which is required to provide compressibility and grounding through the spheres or other conductive material when the apertures are made of proper diameter with relation to the diameter of the contact pins or contact sockets mut be provided.
In conjunction with the hardness (or softness) of the elastomer or rubber material of thegasket 22, orlayer 84 ofgasket 82, the dimensions ofgasket 22 or 82 in the configuration is critical. Theelastomer gasket 22 or elastomer lawer 84 (or gasket 82) should be in the approximate range of sixty to ninety durometers hardness. The compression eifected both in the transverse direction along the pins and the lateral direction must assure good conductivity. The aperture size, flexibility, and gasket layer thickness are critical. The gasket must be thick enough or because of the metal layers appear thick enough to bypass incoming noise. frequencies or to reflect incoming noise frequencies as will be explained hereinafter. Also, thegasket 22 thickness must be sutficient, such that upon displacement compression, the silver or other conductive filler is not prevented from making good contact. The aperture size must be such as to provide an interference fit with the contacts such that both transverse and lateral compression results. However, thedeformable gasket 22 or 82 must not be laterally displaced so as to cause substantial misalignment of the apertures in which thecontact sockets 29 or pins 70 fit. Aperture sizes of about .057 inch with a pin outside diameter of .063, for example, are satisfactory.
In the illustrative embodiment maximum attenuation of RF noise over the frequency range of 30 mHz. to 10 gHz. must be attained and at least a 40 to 50 decibels attenuation is desirable. To attenuate signals above 30 mc. representing unwanted noise frequencies, the connector contacts must be of size and configuration in conjunction with thegasket 22 or 82apertures 37 or 86 and must be emplaced to exert pressure against the conductive material in thegasket 22 or 82 such that grounding of the unwanted signals is assured. Additionally, the structure must be flexible to avoid damage to the fragile tiny contacts. Thus, the size of the apertures in the gasket is critical because when theconnector contact sockets 29 or pins 70 are emplaced through theapertures 37 or 86 the connectors must apply force to the silver layers or other conductive material in the gasket such that contact ground (that is to the chassis) is assured so that return line feedback is obtained. However, theapertures 37 or 86 must not be so undersized as to make it virtually impossible to remove the contacts without breaking them or to permanently embed the connectorfilter contact pin 70 or filterconnector contact socket 29 into thegasket 22 or 82.
Refer to FIG. 10. As will be explained this embodiment of the gasket member which may be provided in the FIGS. 1-5 combinations or in the FIGS. 6 and 7 combinations to be described comprises a plurality of rubber or elastomer non-conductive thin layers orlamina 84 and alternate metal foil or metal coating layers orlamina 83 which may be provided and suitably secured together to form agasket 82.Apertures 86 corresponding to apertures 37 ofgasket 22 are formed and also are sized to provide an interference fit therein offilter contact sockets 29 or pins 70 (or dummy contacts not shown). The metal foil or metal coating layers are peripherally extended inwardly into theapertures 86 to contact thefilter 59 outer electrodes 63. A feature of the alternate metal layers and nonconductive material filled elastomer layers is that a plurality of parallel paths to theshield 23 are provided. The efifect of the parallel conductive paths is to increase the overall conductivity, that is lower the total resistance to ground thereby supplying desirable, and in some instances, critical means of providing a more conductive path to ground.
The filter support andisolation block 24metal layer 30 surface bears in the transverse direction against the deformableconductive gasket 22 or 82 to compress the gasket in the transverse direction. This compression in the case ofgasket 22 helps to assure the conductivity of thegasket 22. For this purpose the flange 31 is made of greater transverse thickness with relation to the depth of aperture 20 so that without securing the spanner nut 28 a predetermined amount of clearance is present between the bottom portion of the flange 50 and the top surface 36 of the shieldingenclosure 23. Upon tighteningnut 28 thegasket 22 or 82 is compressed and this clearance removed. Additionally a conductive grounding path is provided by the compression of thegasket 22 or 82 by theRFI shielding enclosure 23. TheRFI shielding enclosure 23 is clamped in place by the mountingbolts 27 which secure the assembly of thegasket 22 or 82, andthe'connector body 21 to chassis 26. The tightness of the clamp ing action ofbolts 27 causes a compressing pressure to be exerted on the elastomer orrubber gasket 22 orlayers 84 to assure the conductivity.
The connector section should be provided completely with filter pins or dummys. If some of the pins are not filter pins, recontamination will occur and make all of the filter pins ineffective. The connector of the invention attenuates 100 mc. incoming unwanted noise frequencies about 45 db (decibels) and here is approximately exponential increase in attenuation of higher frequencies to the 10 gI-lz. or 10,000 mc. noise inputs which are attenuated about db. About 40 db attenuation is normally acceptable for the purposes in a connector such as that of the invention is to be utilized. The problem becomes increasingly troublesome at the middle frequencies around a l0002000' me. (1-2 gHz.) range. That is, at l gI-Iz., 50 percent of the unwanted noise propagates through the contact and into the equipment without thefilter 59. At about 10 gHz., because of RF reflected energy there is no propagation of noise into the electrical equipment. At 1 gHz. 50 percent of the noise is propagated and the RF signal passed by the filter must be Well grounded.
From 30 to 500 me. thefilter 59 and deformableconductive gasket 22 are elfective in eliminating the noise at those frequencies with the compression due to the interference fit of thefilters 59 in theapertures 37 and the compression provided by tightening theRFI shielding enclosure 23 bybolts 27 to the frame and by tightening the filter support andisolation block 24 by jackscrew 25 against thegasket 22. Some attenuation is thus provided without the metal undercoating layer on the filter support andisolation block 24. However, a marked increase in attenuation is provided by thecoating 30. Between the 8l0 gHz. range and above, substantially no propagation goes down the connector contact into the electrical equipment because the energy is totally reflected. A serious problem arises from noise freqeuncies from 500 me. to 8000 me. (or 8 gHz.). In this range about percent of the energy is propagated down the line and the filter effect is not adequate because the conductive filledrubber gasket 22 does not provide a good enough ground in conjunction with thefilter 59. Because of the stress relieving phenomena of the rubber under compression, effectively only a very thin conductive layer is present adjacent the walls (electrode 63) of thefilter 59 and at the portion of the rubber gasketadjacent block 24. At the frequencies above 500 me. the conductive layer provided bygasket 22 is too thin for maximum effectiveness and some thickness of layer is required to provide proper RF reflection and RF grounding. To take care of RF noise attenuation between 500 me. and 8 gHz. either provision of the FIG. 10 embodiment gasket of multiple layers comprising alternate elastomer material layers and thin metal painted or foil layers or the provision ofmetal layer 30 is suitable. The painting or metal foil should preferably extend inwardly into the aperture filter edge contacting portions. The series of thin conductive paths created by the conductive coatings or foil layers 84 on each of the elastomer conductive material filled layers extended to theshield 23 accomplishes the purpose of the compressible path along thefilter 59 edge. The filter support andisolation block 24 also prevents thecontact sockets 29 or pins 70 from bending at the connector entrance area as well as providing for compression on thegasket 22 or 82 material.
Restating, even with the compression provided by making the pins fit withan interference fit in theapertures 37 or 86, respectively, of the deformableconductive gasket 22 or 82 and with the compression exerted by the shieldingenclosure 23 and the underside of theboss 21, the conductivity through the gasket is not suflicient at the middle frequencies of 500 megacycles to 8 gHz. There might be an attenuation of only 20 dbs rather than the 40 dbs required for example. For this reason, either theconductive layer 30 is provided to enhance the conductivityor thegasket 32 formed of the laminated elastomer layers 84 and solid foil layers or both are provided so as to increase the conductivity. The foil (or metal coated) layers 83 and layers 84 are apertured withapertures 86 to receive thecontact sockets 29 or pins 70. Thus, to provide a better conductive path to the shielding can orenclosure 23 and therein to ground, the bottom surface of theisolation block 24 boss 31 is coated with silver or otherwise provided with an aperturedconductive layer 30.Conductive layer 30 may be provided by a silver spray or by rolling silver onto boss 31 or by plating boss 31, for example.
Refer again to FIGS. 1, 4 and 5. The boss 31 of the filter connector support andisolation block 24 is of greater thickness than the aperture 20 of shielding can 23 such that is, protrudes beneath the aperture 20 of the shield, that is, beyond the wall of surface 36 and compresses thegasket 22. The surface of boss 31 is also coated with a highly conductive metallic coating or laminated with ametal foil layer 30. The boss 31 is made thicker than the depth of the aperture 20 to enable pressing against the deformableconductive gasket 22 upon securing the jackscrew andboss 25 such as by a securing force, for example, of about two ounce-inches. Thelayer 30 and/or the FIG. 10'embodiment gasket 82 provide structure that enchances the reflecting of the higher noise frequencies such as 8 to 10 gI-Iz. !back so that such high frequency noise is not propagated into the electrical equipment.
Refer to FIG. 5. It is important that theconnector contact sockets 29 and pins 70 be removable. For this reason, retaining clip member 46 and the corresponding structure of reducedsleeve 45, bevelled stopportions 43 and 44 and the other portions of thecontact sockets 29 and pins 70 are of configuration and size in conjunction with the aperture size of theconnector body 21apertures 37a, the connector contact support andfilter block 24,apertures 37b, thegasket 22 or 82, apertures 37 (and corresponding apertures in the FIG. 5 and FIG. 6 connector sections) such that room is provided between thesocket 29 orpin 70 andaperture 37a and a tool (not shown) required to compress the flaring portion 66 of retaining clip 46 back from stop shoulder 43 into double bevelled aperture or corresponding elements of clip 96 into connector body double bevelledaperture 79 of pin connector section assembly of FIG. 5 or the FIG. 6 assembly for disassembly of theconnector socket 29 orconnector pin 70. For this reason a loose connection is required with room for the tool between theconnector body 21,aperture 37a and the filterconnector contact socket 29 orpin 70 peripheral surface. Thegasket 22 or 82 is provided withapertures 37 or 86, respectively, which are smaller in diameter than the filter S9 or 97 diameter but since the gasket is yieldinglydeformable filter 59 or 97 is not hurt on being inserted through theaperture 27 or 86. This diameter size relationship between the filters peripheral surfaces and the gasket apertures causes an interference yet flexible fit of the filter in engaging the gasket walls of thegasket apertures 37 or 86 to provide not only electrical connection of the filter capacitor outer electrode 63 to ground in order to attenuate the high frequency noise or unwanted signals, but it also provides a yieldable but firm support for the otherwise looselyfitting socket 29 orpin 70 which prevents damage to thesocket 29 orpin 70. Thesocket 29 orpin 70 is of dimensions such that by itself it is extremely fragile. However, because of the resiliency, springiness, flexibility, supple ness and elasticity material of the deformableconductive gasket 22 or 86 thepin 70socket 29 is held firmly in place. In addition to being held firmly, thepin 70 orsocket 29 is held yieldably so that any shocks will be absorbed by the springy and resilient material of thegasket 22 and yet permit removal. This feature of providing a good electricalcontact and yet permitting removal of thepin 70 orsocket 29 without loss of pin or socket density and still making the gasket apertures large enough and the gasket thick enough and of proper hardness to avoid socket or pin misalignment is a feature of the present invention. It is often a requirement that a certain amount of connectors per square inch must be provided in the space allotted. Further, the connection of the pins must not be permanent but the pins and contacts must be removable for replacement or other reasons. By utilizing the conductive material impregnated rubber orelastomer material gasket 22 of suitable hardness, and an adequate number and size of conductive spheres (or adequate other conductive materials), the advantages are obtained of good electrical connection, vibration damping and substantially eliminating need for some close machine tolerances and dimensions. Close tolerances are provided on the outside diameter of thefilter contact pin 70 orsocket 29 with respect to theconnector body 21aperture 37a such that thefilter connector socket 29 orpin 70 will be closely fitting yet enable a tool to be pushed therearound for disassembly and assembly purposes without appreciably affecting the physical characteristics of thepin 70 orcontact 29. However, the tolerance with respect to the rubberconductive gasket 22 is much less critical. This permits temperature variation and variation in manufacturing of the pins and the rubber gaskets (thickness-wise but not aperture-wise). The compression of the rubber or elastomer material ofgasket 22 by the adjacent filter capacitor plate 63 facilitates the electrical bypassing of high-frequency unwanted signals to ground and also prevents RF energy from traveling along the outside of thesocket 29 orpin 70 into the enclosure to which connection is to be made. It is apparent that this structure and description is also applicable to the FIGS. 6 and 7 embodiments to be described.
Refer to FIG. 8. As is apparent from that schematic representation where the path to ground is not sufficiently conductive, the impedance Z1 of the rubber causes coupling of the unwanted signals into the enclosure rather than bypassing the high-frequency unwanted signals to ground.
Refer to FIG. 9. With a relatively high impedance Z2 between the pins there exists a commonly shared impedance which causes coupling of the signals betweensockets 29 or pins 70. The tuned circuits in FIG. 9 represent the characteristics of pairs ofsockets 29 or pins 70. The lowering of the resistance or impedance Z1 by the provision of the proper FIG. 1 or FIG. 10 deformable gasket material and parameters (FIG. 8) avoids unwanted coupling of the different signals or voltage carried by different pins 70 (or sockets 29). This effectively eliminates cross-talk by providing a very low resistance between the pins yet avoiding actual contact. The invention is therefore applicable to small closely spaced pins 70 (or contacts 29). Without the high conductance of theconductive gasket 22 or 82 as combined in the invention an unwanted inductance and therefore coupling and cross-talk between two connector pins would occur.
Refer to FIGS. 1 and 5.Connector body 57 which contains pins 70 has an upstanding rectangulartubular boss portion 56 hollowed out to provide protection for the pin ends 69 and is dimensioned to fit in closely mating relationship over the protruding boss section 21a ofconnector body 21. This interfitting also causes thepins 70 to align themselves with the respective sockets so that a good connection between all of the contact pins 70 andcontact sockets 29 is maintained. A nonconductive interfacial seal 71 is provided and enclosingly covers the pin containingbody member 57 to prevent moisture and other ambient contaminating conditions from adversely affecting the transmission of signal and power voltages. The remaining elements of the pin retaining connector section comprise an elastomer or rubberconductive section 92, a connectorcontact support block 84, and ashield 93. As in the case of the filterconnector contact socket 29, thegasket 92 is of conductive elastomer material filled with a conductive filler or instead gasket 82 may be provided, theconnector body 57 is of non-conductive dielectric material and the connector pin support block 94 is of non-conductive dielectric material having a metal layer (not numbered) corresponding to layer 30 ofblock 24. Corresponding tosocket filter 59 which has been described hereinabove, apin filter 97 is provided. A pin retaining clip 96 (similar to described clip 46) is provided for eachpin 70 and is configured to permit insertion into the apertures (not numbered) of block 94,gasket 92,connector body 57, connector end seal 71 and removal by assembly tools as in the case of the contact socket retaining clip 46 as will be described hereinafter.
18 Refer to FIGS. 4 and 5. The uncoated portion of the outer electrode 63 of the socket filter capacitor is in continuous direct contact around its periphery with the elastomer or rubberconductive gasket 22, orgasket 86 where utilized in the combination, and extends partially into the connectorcontact support block 24 and thefilter connector body 21. Thedielectric coating 56 on the ends of the socket filter and the remainder of the contact socket extends through adjacent portions of theconnector body 21 and theblock 24 and protects against shorts. Similarly, the filter contact pin, conductive electrode uncoated portion of the outer electrode of the filter capacitor (not numbered) is in continuous direct contact around its periphery with the elastomer or rubberconductive gasket 92, or laminated metal and deformablenon-conductive layer gasket 82 and extends partially into the connector contact support block 94 and theconnector body 57. The dielectric coating on the pin filter (not numbered) is similar todielectric coating 56 of thesocket 29 and the remainder of thecontact pin 70 extends through adjacent portions of theconnector body 57 and the block 94.
Each of the connectorsocket retaining apertures 37a in the connector body 21 (and each of the pin retaining apertures in the corresponding connector body 57) comprises a smaller diameter aperture (orconnector body 57 smaller diameter aperture 79) chamfered at both ends into which the retaining clip 46 (retaining clip 96 for the pin) is disposed, the chamfered aperture ends forming two bevelled shoulders between which the retaining clip 46 is retained around the contact socket reduced diameter portion 45 (retaining clip 96 around reduced diameter portion 75 for the pin 57) to retain the filter connector contact sockets 29 (or connector contact pins in the opposite connector) in fixed position in respective alignedapertures 37 b, 37 and 37a.
One of the features of the connector of the invention is that the filterconnector contact sockets 29 and pins are readily insertable and removable. Acontact socket 29 is inserted by first inserting thecontact receiving portion 67 throughsuccessive apertures 37b, 37 and 37a. Theconnector apertures 37b of theconnector support block 24, and the portion ofaperture 37a of theconnector body 21 nearest thegasket 22 are of greater diameter than thesocket 29 orpin 70 largest outside diameter to permit insertion therethrough. The portions of thesocket 29, inserted first, tubularcontact socket portion 67, tubular reducedcontact socket portion 68 which contains a contact spring therearound and tubular contact socket sleeve portion 38 are of lesser diameter than the reduced diameter double bevelled aperture 65 withinconnector body 21. The connector apertures 65 may be each formed by molding or other-wise forming a counterbore at each end of the connector aperture which terminates in a bevelled rear portion and a space between the two apertures defines the reduced diameter double bevelled aperture 65. Upon insertion, at theconnector body 21 and a tool having a front sleeve end which resembles a leadless mechanical pencil, and which advances in peripheral surrounding relationship around successive tubularcontact socket portions 67, 68 and 38, may be provided and facilitate pushing of the open slot end 66 of retaining clip 46 and hence the retaining clip 46 into the space between the bevelled surface of the reduced diameter aperture 65 and the reduceddiameter socket section 45 to permit insertion of the contact pin. Upon release of the tool member, the flaring flange 66 of the spring retaining clip means 46 will spring into place surrounding adjoining chamfered contact socket portion 43 and movement of the contact socket (retaining clip 96 similarly locks the contact pin in place in the contact pin retaining connector section) in either direction will be prevented. In this condition the reduced tubular portion 61 and a portion of the outer filter capacitor surface covered by thedielectric paint 56 is within theconnector body 21 and the conductive surface of the outer electrode 63 of the filter capacitors C1 and C2 is held in interference fit relationship in theaperture 37 of deformableconductive gasket 22. The last to enter portion of thetubular filter 59, which is surfaced with thedielectric paint 56, including dielectric surfacing over the solder 48, is retained in theconnector support block 24. The dielectric coating material guards against shorting of the signal or power high voltage from the contact socket to ground along the rubber or elastomerconductive gasket 22. In assembled condition thecrimp barrel 39 and reduced tubular portion 40 are also contained in theconnector block body 24 aperture and embedded slightly from theouter block 24 surface. The tubular contact socketpin receiving portion 67 is also embedded slightly below the end face of theconnector body 21 when in assembled condition.
Refer to FIG. 4. Outer electrode 63 on thefilter contact socket 29 makes a physical and electrical contact with the groundinggasket 22 necessary for the pi filter network. The retainer clip 46 retains thecontact 29 within the moldedconnector body 21 by a jam type feature as described hereinabove. It will be understood, of course, that other tpyes of retention means than the jam type illustrated might also be introduced without departing from the principles of the invention.
Removal of the contact socket 29 (or pin 70) is effected by means of a simple extraction tool (not shown). The tool comprises a right cylindrical sleeve which fits around the tubular pin receiving andsleeve portions 67 and 38 and which compresses the flange 66 of spring retainer 46 such that it is withdrawn into the pace around the reduceddiameter socket section 45. The tool further comprises a central retractable and insertable pin which pushes the contact socket 29 (or pin 70) through the reduced aperture 65 and the socket 29 (or pin 70) may be readily withdrawn through theapertures 37 and 37b to be removed. Thus, the contact socket 29 (or contact pin 70) can be removed for rewiring or replacement. Together with seal 71 and of itself,deformable gasket 22 provides a sealing feature against harmful environment such as ambient moisture. Thedielectric coating 56 prevents shorting by contamination or by conductive particles. Because of the high resistance afforded by the dielectric 56, increased reliability is obtained and the possible electrical creepage path of B+ voltage to ground is increased. This provides improved high voltage breakdown characteristics and insulation resistance.
It should be understood that a filter connector section is not normally used with a filter plug connector section where the attenuation, which would be the end result normally, is not needed. A standard non-filter mating connector section is therefore normally used.
As will be described in description of FIGS. 6 and 7 hereinafter, although the above-described embodiments show grounding on a standard rack and panel-type connector, it is contemplated and within the scope of the invention that the means of the invention could be provided at the interface of a standard plug receptacle connector and the filter contacts may be housed within an enclosure that permits its use or removal in the event it is not used.
Refer to 'FIG. 6. FIG. 6 illustrates a second preferred illustrative embodiment of the combination of the invention wherein there are provided a filter connector section 121, a standard (no filter) socket connector section 122 and a standard (no filter)pin connector section 123. Connector section 121 is structured and located to interfit at the interface betweensections 122 and 123. Socket connector section 122 andpin connector section 123 may be conventional connector sections available from the Hughes Aircraft Company, Newport Beach, Calif. Theconnector comprising sections 122 and 123 is provided with a connector polarizing and securing orjackscrew device 125 to clamp the securing orconnector sections 121, 122 and 123 together. The socket connector section 122 holds the contact sockets 129' which are provided. Socket section 122 comprises awire guide 124, a sealing gland 141 to prevent moisture and other ambient atmospheric conditions from adversely affecting the connector performance, and asocket connector body 131 which may be molded as in the case ofconnector body 21 of FIG. 1.Aligned apertures 167, 168 and 169 of socketconnector section block 124, gland 141 andbody 131 are respectively provided and contain contact sockets 1'29. The connector sockets 129 may be regular (without a filter) sockets of the type obtainable from the Hughes Aircraft Company and designated WS22Y22C000. Similarly,pin connector section 123 is provided to hold the contact pins 149.Pin section 123 also comprises asup port block 134, apin sealing gland 151 and apin connector body 161. The connector body pins 149 may also be the regular connector contact pins of the type obtainable from the Hughes Aircraft Company under the designation WP22Y22C000. Retainingclips 136 and 137, similar to the retaining clip 46 of the FIG. 1 filtercontact socket device 29, may also be provided. In the filter connector section 121 are provided a pair of insulating material filter body blocks 1'27 and 128. Filter blocks 127 and 128 are formed of insulating material. Sandwiched between theblocks 127 and 128 is provided ground plane gasket 100. Gasket may be formed of an elastomer material filled with conductive filler and having critically sizedfilter retaining apertures 114, similar togasket 22 of the FIG. 1 embodiment. Gasket 100 is preferably of greater diameter than the diameters of the insulating material filter body blocks 127 and 128 and terminates in an annular rounded section 113. A floating ground shell orRFI shielding enclosure 99 which may be formed of metal is provided.Shell 99 is configured to encircle or surround the periphery of the connector filter section 121 and a portion of the periphery of thesocket connector body 131. Shieldingenclosure 99 slides transversely over annular rounded section 113 and provides shielding isolation from extraneous radio frequency noise. Afilter 106 is provided. As in the case of the grounding to the shielding can 23 of the deformableconductive member 22 in the FIGS. 1 and 4 embodiment, thefilter 106 is grounded through the conductive elastomer ground plane gasket 100 to the floatingground shield 99. The floatingground shield 99 has an apertured flange 103 through which it is rigidly bolted by provided bolt means 101 to theframe 102 which may be the frame of i an electronics equipment into which shielded connection is to be made. Theframe 102apertures 133 contain the bolts 101. A nut 104 secures theshield 99 to the frame and also connects thesocket connector body 131 through aflange 134 securely to the other side of theframe 102 to thereby provide radio frequency noise shielding around the periphery of the connector. Theshield 99 is slidably disposed along the length of a portion of theconnector body 131 and of filter section 121 such that it contacts the deformable conductive gasket 100 at a point depending upon the transverse position of the floatingground shell 99. The point at which the floating ground shell contacts the gasket 100 is determined by the thickness of the electronic equipment frame orchassis 102. Thus, a self-adjusting feature of the floatinggrounding shield 99 is provided since a good ground will be established through gasket 100 of the filter outsidecapacitive electrode 105 of thefilter 106 which is provided.Filter 106 may be identical to that shown in the FIG. 2 embodiment and will not be described herein. That is, thefilter 106 comprises a tubular inner member upon which is mounted a plurality of ferrite beads (not shown in FIG. 6). Disposed upon the ferrite beads, as in the case of the FIG. 2 embodiment, is a tubular ceramic core (not shown) which has a pair of highly conductive gold or silver elertrodes (not shown) coated on the inside surface and asingle electrode 105 coated on the outside surface. Thefilter 106 is provided with amating pin member 109 to fit into the pin receiving aperture 107 of socket connector section 122 and amating socket 110 on its opposite side of thetubular filter element 105 to receive the pin 138 of pinconnector contact section 123. In view of the detailed discussion hereinabove of the assembly of the connector contact sockets and pins and the securing of the tubular filter member by solder, further discussion to this end is not presented. In the fashion described for the embodiment of FIG. 10 the conduc tive elastomer ground plane gasket 100 alternatively may be made of laminated non-conductive material filled elastomer and metal foil or coating layers. Optionally, the conductive elastomer ground plane gasket 100 may be cemented to one or both of the insulating material filter body blocks 127 and 128. A pair ofinterfacial seals 143 and 144 which may be formed of silicone rubber and have doughnut-shaped pin sealing features similar to seal 71 of FIG. may be provided. Thefilter body block 127 has a reducedconnector aperture 111 bevelled at both ends similar to aperture 65 of FIG. 1 and aretaining clip 112 similar to clip 46 of FIG. 1 is provided.
The retainingclip 112 is secured in reduceddiameter aperture 111 bevelled at both ends in the manner shown and described for retaining clip 46 of the FIG. 1 embodiment and its details need not be repeated herein. As in the case of that embodiment, this feature enables removability of thefilter adapter 106 from the filter connector section 1 21 for insertion of areplacement filter adapter 106 as desired. As described in the description of FIG. 4, upon disassembly of thepin 109 of thefilter adapter 106 from the filter connector section 121, a tool (not shown) which may resemble a hollow tube may be inserted to bend the edge of the retainingclip 112 and to retractclip 112 into theaperture 111 whereby a. central rod member of the tool may push thepin 109 and hence thefilter contact 106 out of the filter connector section 121.
Refer to FIG. 7. A disassembleablefilter connector section 170 is provided. A deformable conductive gasket 171 and filter connector body blocks 173 and 174 similar to respective gasket 100 and filter body blocks 127 and 128 are provided. Optionally, one side only, as shown in FIG. 7, or none of the sides of the conductive gasket 171 is bonded or cemented to the surroundingconnector body members 173 and 174. In this embodiment, the structure similar to the reducedaperture 111 and retainingclip 112 may optionally be not employed, as shown in FIG. 7, or employed. The filter connector body blocks 173 and 174 are each terminated by capturing closed entry means 175 and 176. Capturing closed entry means 175 and 176 comprise bevelled constricted end entryapertures forming shoulders 179 and 180. Individualfilter connector contacts 172, similar tocontacts 106 of FIG. 6 but with a squared-off shoulder, and without the retainingclip 112 structure, and two protrudingpins 177 and 178, are provided. The individualfilter connector contacts 172 are contained such thatpin 177 is secured within the socket 107 of the regular connector contact 129 (see FIG. 6) and thepin socket 178 is secured within a similar regular connector contact socket 107 (see FIG. 6) of another connector contact socket 129. Thus, without cementing of the gasket 171 to either or both of thefilter connector bodies 173 and 174 and without thespring retaining clip 111 the FIG. 7 filter connector section is held assembled without possibility of leakage. That is, without cementing of one or both sides of the conductive elastomer gasket 171 to thebodies 173 and 174, due to theshoulder 180 surrounding thesmaller pin 177 circumference and the shoulder 179 surrounding thesmaller pin 178 circumference to close off both sides a rigid enclosed structure is provided by capturing closed entry means 175 and 176. A fastening means 181, 182 and 183 is provided to fasten the one or both of thefilter connector bodies 173 and 174 together. The filter connector section of FIG. 7 may be readily disassembled by unfasteningmeans 181, 182 and 183 and by then removing one connector body and finally by removing theinside filter 172. It will be understood, of course, that if desired a central filter unit for the FIG. 6 embodiment which is disassembleable and structured similarly to the FIG. 7 embodiment but with a socket end instead ofpin 178 may be provided and is contemplated by the teachings of the present invention. Also a double socket ended device similar to FIG. 6 but structured to mate with two regular (no filter) pin sections is contemplated.
Thus, the illustrative embodiment of the present invention illustrates a connector combination including RF noise energy filter, shielding, reflecting, isolation and grounding means which provide maximum attenuation and reflecting back of RF over a desired frequency range, for example, the frequency range of 30 mHz. (megahertz) to 10 gHz. (gigahertz). For this purpose the invention provides means wherein a filter (which may be a pi filter) incorporated within the connector socket or pin structure has a capacitor plate of the (pi) filter connected to reference voltage (ground) via a low impedance path means which path means also is structured to enhance reflection of certain noise frequencies. The filter may, for example, be tubular and fit over a portion of the socket or pin and the grounded capacitor plate may be a common external plate opposite two internally disposed plates of the tubular pi filter. The low impedance path may comprise a gasket. The gasket of the invention is so structured that it possesses the required minimum coupling between physically adjacent filters, as well as providing a low impedance path to ground. The gasket may be rubber or elastomer material filled with conductive filler or comprise a laminated structure of layers of rubber or elastomer and thin layers of metal. To obtain the minimum impedance of the gasket, the gasket material is made deformable and is pressured by a shield enclosure and a contact support and isolation block and by contacts inserted in the gasket apertures. The pressure on the gasket of the inventive combination provides physical contact of the conductive particles which may be, for example, silver-plated spheres suspended in rubber or elastomeric gasket material and it insures adequate physical contact, and thereby electrical contact, between the conductive material embedded in the gasket and the filter capacitor plate and a low resistance path between such contact and the reference ground plane (the shield and frame). The invention also provides for parallel paths to the grounded shield to enhance conductivity and provide for interfacing a filter unit containing connector section shielded and configured in accordance with the teachings of the invention and wherein the filter unit may be provided for optional use or removal at the interface of regular pin containing and socket containing connectors. Further, the filter unit containing connector section may be readily disassembleable. Also, such a disassembleable unit may be provided to mate with two regular connector pin sections, with two regular connector socket sections, or with one regular connector contact pin and one regular connector contact socket section.
While the principles of the invention have now been made clear, there will bevimmediately obvious to those skilled in the art many modifications in structure, arrangement, proportions, the elements and components used in the practice of the invention, and otherwise, which are particularly adapted for specific environments and operating requirements without departing from those principles. While salient features have been illustrated and described with respect to particular embodiments, it should be readily apparent that modifications can be made within the spirit and scope of the invention, and it is therefore not desired to limit the invention to the exact details shown and described.
What is claimed is:
1. A connector comprising:
(a) a deformable gasket of structure and material content to have enhanced conductivity to certain noise frequencies of energy under compression,
(b) a plurality of contacts, each comprising a tubular filter portion mounted therearound,
(c) grounding means in a first pressurizing contact with said gasket and totally surrounding the circumference of said gasket,
(d) said gasket being ape-rtured with apertures of size such that the filter portion of a said contact is removably retained in pressure fitting engagement therein, and
(e) an isolation block movably secured in a second pressurizing contact with said gasket to compress said deformable gasket to assure conduction of said certain noise frequencies of energy.
2. The connector of claim '1 wherein:
(a) said isolation bloc kfurther comprises a metal surface layer bearing upon the surface of said gasket, to provide reflecting of certain unwanted frequencies of energy and provide an increased conductive path to said grounding means from said contact filters through said gasket.
3. The connector of claim 1 wherein:
(a) said gasket comprises layers of deformable material and layers of conductive metal to provide parallel electrical paths between said filters and said groundin-g means to enhance conductivity of said gasket and to enhance reflection of said certain noise frequencies of energy.
4. The connector of claim 1, said connector further comprising:
a) a connector body,
(b) said connector body and said isolation block being apertured with apertures of larger diameter than said gasket to removably retain said contacts, and
(c) means to secure said body, said gasket and said isolation block in said compressed relationship to compress said deformable gasket.
5. The electrical connector of claim 1 wherein:
(a) said gasket further comprises alternate layers of deformable non-conductive material and thin metal coatings to provide parallel paths of lowered resistance to the shield ground and to provide a sufficiently thick appearing surface to reflect certain unwanted RF noise frequencies.
6. The connector of claim 4 including:
(a) metal shield enclosure and a frame forming a chamber of size such that said chamber contains said gasket and a portion of said body member and constricts said g-asget therein,
(b) said metal shield enclosure having an aperture,
() said isolation block securable means comprising a raised boss of thickness greater than the depth of said shield aperture, and
'(d) said boss being superimposed upon the face of said gasket and securing said isolation block, said deformable gasket and said body together such as to constr-ict said deformable gasket.
7. The connector of claim 6 wherein:
(a) said isolation block boss further comprises an apertured metal layer disposed at the interface between said gasket and said boss.
8. The connector of claim 1 wherein said contact filter 24 (b) said gasket having a plurality of apertures, (c) a plurality of connector contacts, (d) said contacts and said gasket apertures being relatively configured and sized such that at least a portion of said contacts are removably retained in said apertures in contactingly fitting relationship, and
(e) means comprising a metal layer positioned contiguous to said gasket to enhance conductivity by providing a parallel conducting path for said lower frequency A.C. signals and to enhance reflection of said range of higher frequency A.C. signals.
10. The electrical connecting means of claim 9 and further comprising:
(a) a contact support and isolation block,
(b) said block comprising a protruding boss,
(c) means to secure said gasket and said block under compression such that said boss faces and applies pressure to said gasket to assure conductivity of said gasket,
(d) said metal layer being disposed at the interface between said boss and said block facing surface of said gasket.
11. The electrical connecting means of claim 9 wherein:
(a) said contacts comprise integral filter means,
(b) said contacts are positioned with relation to said gasket apertures such that said filter means contact the gasket walls defining said apertures,
(c) said integral filter means further comprise an outer electrode and conductive means to provide a conductive path and retain said filters on said contacts, and including (d) dielectric means superimposed on said outer electrode at its end portions thereby preventing electrical short circuits by increasing the length of surface creepage paths.
12. The electrical connecting means of claim 9 wherein:
(a) said deformable gasket comprises at least one layer of elastomeric material and at least one layer of relatively thin metal.
13. The electrical connecting means of claim 10 and further comprising:
(a) a conductive material shield configured to define a chamber removably retaining said gasket,
(b) said shield having an aperture therein, said boss of said isolation block being retained within said shield aperture,
(0) said boss being of greater thickness than the depth of said aperture,
(d) said means to secure said block into said aperture thereby applying said boss of greater thickness than the depth of said aperture against said deformable gasket to thereby provide compression of said boss against said deformable gasket.
14. The connector of claim 9 wherein said gasket, said contact and gasket aperture relative sizes, and said means comprising a metal layer are structured to enhance conductivity of said lower frequency A.C. signals and enhance reflection of said higher range A.C. signals to suppress said A.C. signals over a frequency range from about thirty megahertz to about ten gigahertz.
15. An electrical connector to provide radio frequency shielding, to reflect unwanted noise of certain frequencies,
and to prevent propagation of unwanted noise of certain other frequencies into eletronic equipment having a frame at electrical ground comprising:
(a) a pair of mating connector sections oppositely mountable on said electronic equipment frame, (b) at least one of said connector sections comprising a connector body, a deformable conductive gasket, a shielding enclosure and a filter contact support and isolation block, (c) said body, said gasket and said block being aligned and each having a plurality of apertures, said body, gasket and block apertures being aligned,
portion, deformable gasket, grounding means, and isolation block, are structured and of material to provide attenuation and reflecting of said noise frequencies of energy over a frequency range from about thirty megahertz to about ten gigahertz.
9. An electrical connecting means comprising:
(a) a gasket of structure and conductive material content such that it is substantially reflective to a predetermined range of higher frequencies of A.C. signals and is deformable under pressure to be selectively more conductive to a predetermined range of lower frequencies of AC. signals,
(d) a plurailty of filter connector contacts disposed in said aligned apertures,
(e) said shielding enclosure being of conductive material and surrounding the periphery of said body and said gasket and configured inside to interfit over the body and gasket in closely interfitting pressure applying relationship,
(f) means to secure said shielding enclosure to said frame,
(g) said shielding enclosure having an aperture through its end opposite the frame secured end,
(h) said gasket apertures being formed of lesser size diameters than the diameters of said connector contacts for protective but removable retention of said contacts and so as to provide deformation of said gasket by said contacts,
(i) said filter block comprising -a filter block body having a surface, resting upon the shielding enclosure surface surrounding said shielding enclosure aperture, and
(3') said block further comprising a protruding boss of thicker dimensions than the depth of said shielding enclosure aperture to thereby apply compression to said gasket and assure conductivity of said gasket, to certain A.C. signal frequencies,
(k) said boss further comprising a conductive layer disposed at the interface between said boss face and the face of said gasket to thereby provide an enhanced conductive path to said shielding enclosure through said gasket and to provide reflection of certain unwanted noise frequency energy to prevent propagation of said unwanted noise frequency energy into said electronics equipment.
16. The apparatus of claim wherein:
(a) said gasket comprises a laminated structure,
(b) said laminated structure comprises alternate deformable material layers and thin metal layers to thereby provide increased conductivity by providing parallel paths for noise energy through said gasket and providing a layer which appears thick to noise energy at certain RF frequencies to thereby enhance reflection of said noise frequencies of energy and to prevent propagation of unwanted RF frequency energy into the electronic equipment.
17. The apparatus of claim 16 wherein:
(a) said metal layers and said deformable layers are apertured and wherein said metal layers extend into the side Walls of said deformable material apertures.
18. An electrical connector attachable to a frame, said connector comprising:
(a) a first filterless connector contact retaining section and a second filter connector contact retaining section,
(b) means to secure said first and second connector contact retaining sections together,
(c) a plurality of first filterless connector contacts and second filter connector contacts extending respectively through each of said sections, said first section contacts being mated to said second section contacts,
(d) said filter connector contact retaining section comprising a deformable conductive gasket, and having a plurality of apertures sized to contactingly retain said filter connector contacts therethrough,
(e) a shielding enclosure sleeve transversely adjustably fitted in bearing relationship to the periphery of said filter connector section deformable gasket, and
(f) means to secure said shielding enclosure sleeve so that one end of said sleeve abuts said frame.
19. The connector of claim 18, said connector further comprising:
(a) a third filterless connector contact retaining section,
(b) a plurality of third filterless connector contacts retained in said third contact retaining section and mated to said filter connector retaining contacts at the filter contact ends opposite said first and second mated contact ends.
20. The connector of claim 19 wherein:
(a) said contacts comprise sockets in one of said first and third filterless sections and contact pins in the other filterless section,
(b) said filter contacts comprise a pin on one end and a pin receiving socket on the other end structured to mate in retaining relationship with said filterless sections contact sockets and contact pins.
21. The connector of claim 18, said connector further comprising:
(a) a third filterless connector contact retaining section,
(b) a plurality of connector contacts in said third filterless section,
(c) said first and third filterless contacts being selectively all pins or all sockets,
(d) said filter section contacts comprising double ended extensions, the same configuration to mate with said filterless section selectively pins or sockets.
22. The connector of claim 18 wherein:
(a) said gasket further comprises a cross-sectional portion of larger dimensions than the interior cross-sectional dimensions of said shielding enclosure sleeve whereby said shielding enclosure sleeve is adapted to slide along said gasket in peripheral interference fitting relationship such that a conductive path exists from each of said filter contacts through said conductive gasket to said shield enclosure sleeve.
23. The electrical connector of claim 18 wherein:
(a) said shielding enclosure sleeve further comprises a flange, and
(b) said means to secure said shielding enclosure sleeve further comprises means to secure said flange to abut the face of said frame.
24. The apparatus of claim 18 wherein:
(a) said filter connector contact retaining section comprises a first and a second insulating material connector body disposed on opposite sides of said gasket and apertured to receive said filter connector contacts,
(b) said bodies each being of lesser cross-sectional di mensions than the dimension of said gasket such that substantially frictionless contact with the inside diameter of said shield enclosure is provided.
25. The electrical connector ofclaim 24 wherein:
(a) said filter connector contacts have contact mating extensions,
(b) said filter connector section further comprising a first and a second sealing gland, said gland being of non-conductive material apertured to contain said "filter contact extensions in contacting fit relationship.
26. The connector of claim 18 wherein said filter contacts, gasket, apertures, and said sleeve are of material, structure and relative size such that noise frequencies of the approximate range of thirty megahertz to ten gigahertz are bypassed to said shield or reflected to attenuate and reflect energy of said noise frequencies.
27. A connector adapted to be secured to a frame comprising:
(a) a pair of filterless contact retaining sections and at least one filterless contact retained in each of said sections,
(b) an interfacing filter contact retaining section and at least one filter contact retained in said filter contact retaining section,
(c) said filter contact retaining section comprising at least one connector body and a deformable conductive gasket, said gasket and body having an aperture in which is retained said at least one filter contact in contacting engagement,
(d) a shielding sleeve peripherally disposed around said interfacing filter contact retaining section in slidable engagement to frictionally engage the outer surface of said deformable gasket member, and
(e) securing means adapted to secure said shielding sleeve to said frame in adjustable relationship of said sleeve With respect to said deformable conductive gasket to permit adjustable securing of the shield sleeve to frames of differing thicknesses.
28. The connector ofclaim 27 wherein:
(a) said filter contact retaining section connector body is disassemblable from said gasket, and said apparatus further comprises (b) capturing means which removably retains said at least one filter contact within said filter contact retaining section, and wherein said' filter contact has extensions configured to interfit with said filterless contacts, and
(c) securing means clamping together said gasket and said connector body such that upon disassembly of said securing means said connector body may be removed from said gasket and individual filter connector contact members may be replaced.
References Cited UNITED STATES PATENTS 10 2,379,942 7/1945 Webber 339-60 2,443,654 6/1958 Else et a1. 33960 2,492,742 12/1949 Gresheim 317-257 X 3,322,385 5/1967 May et al. 339-143 X 3,371,147 2/1968 Daubenberger et al. 339'94 X 15 3,123,133 4/1964 Noschese 339-14 RICHA'RD E. MOORE, Primary Examiner 20 US. 01. X33.