US3467891A - Combination electrical,mechanical,and thermal connector assembly - Google Patents

Description

p 16, 1969 R. A. MOGLE A 3,467,891

. COMBINATION ELECTRICAL, MECHANICAL, AND

THERMAL CONNECTOR ASSEMBLY 3 Sheets-Sheet 1 Filed Oct. 8,1967

v92 es 78 INVENTOR:

RODMAN A. MOGLE,

BY We, ZLZW ms ATTORNEY.

Sept. 16, 1969 R. A. MOGL E 3,467,891

COMBINATION ELECTRICAL, MECHANICAL, AND THERMAL CONNECTOR ASSEMBLY Filed Oct. 3, 1967 3 Sheets-Sheet 2 INVENTOR RODMAN A. MOGLE1 BY Mam HIS ATTORNEY.

Sept. 16, 1969 R. A. MOGLE 3,467,891 g COMBINATION ELECTRICAL, MECHANICAL, AND

THERMAL CONNECTOR ASSEMBLY Filed Oct. 5, 1967 3 Sheets-Sheet 5 2767 FIGB RODMAN A. MOGLE,

United States Patent ABSTRACT OF THE DISCLOSURE An improved mechanical arrangement is disclosed for removably attaching a, sub frame to a main frame.

An'edge portion of the sub frame slides into a recess of :themain frame, the edge portion'being hollow and containing roller members in an elongated staggered arrangement so as to exert force laterally along the edge portion in response to axial motion of a cam or toggle device, thuswedging the sub frame securely in the main frame recess. The cam device is arranged to provide a sequence of motions so that it drives the sub frame into locked seatedposition prior to wedging it in place.

t .-Background of the invention 'There are numerous'applications where is it desired to have a movable or removable device which can be quickly secured in place and also quickly released for movement or removal Such an application is frequent in electronic equipmentfcompu'ters for example, in which numerous electronic circuits (usually in the form of printed circuits, or microcircuit modules) are carried by sub frames which are removably attached to a main frame. "The sub frames must be readily removable for testing, inspection" and repair or replacement of the circuits. The sub frames and-main frames are usually made of metal so as to provide a good electricaL'mechanical, and thermal (heat transfer) connection when assembled.

The desired quick connection and removal of the sub frameto and from the main frame (for repair, replacement, etc.) is generally incompatible with the desired high-efficiency or heat transfer. The problem of achieving effective heat transfer has become increasingly severe 'as the packaging density of electronic equip- "ment'has increased with advancing technology, whereby circuits having hundreds of heat-producing transistors and resistors are contained in'a volume of only a few cubic inches'It is desirable to dissipate this heat by conduction rather than providing air-blowing or other cooling means. To dissipate the heat by conduction, suitable large areas of the sub frames must be in good thermal heat-flow contact with the main frame. Usually this is achieved by providing. numerous bolts or clamps to hold the sub frame in tight contact with the main frame. However, it is difficult to arrange the construction to provide for convenient access to these bolts or clamps, and it is timec'onsuming to fasten and unfasten them. Also, a single bolt or clamp can be used, but this requires massive frames (for strength), and accurately finished fiat surfaces, at the contact areas.

Summary of the invention 3,467,891 Patented Sept. 16, 1969 second member having an elongated recess adapted to receive the contact portion of the first member. The contact portion is provided with an elongated opening along at least a part of the length thereof, and a plurality of roller members are positioned side-by-side for rotation about transverse axes in this opening, the roller members having a diameter less than the depth of the opening and being arranged in a staggered alternately offset manner along the length of the opening. A motion mechanism is adapted to move axially in the elongated opening to urge the rollers mutually together, as a reult of which the rollers exert a lateral force and motion thereby wedging said contact portion of the first member into firm and uniform engagement with the sidewalls of said recess of the second member, thus achieving a good electrical, mechanical, and thermal engagement of the members. The motion mechanism may include a take-up spring means for insuring consistent contact pressure.

As a further feature of the invention, the aforesaid motion mechanism is a cam device comprising a rotatable cylinder provided with a helical slot therein. A pin, fixed to the first member, extends into the helical slot of the cam cylinder, so that when the cam cylinder is rotated it moves axially of said elongated opening as determined by the cam action of the helical opening on the fixed pin. Preferably, the motion mechanism further includes an L-shaped slot in the wall of said first member adjacent to the cam cylinder, and the second member is provided with a notch adjacent the position of the L- shaped slot when the two members are in assembled position. A movable floating pin extends through the L- shaped slot and into the helical slot of the cam cylinder at a position above that of the fixed pin. The lower end portion of the helical slot is offset, so as to have no slope, the position of the fixed pin when the assembly is in the released condition, such that, when the cam cylinder is rotated in the direction for tightening the assembly, the movable pin enters said notch of the second member and exerts force axially to cause forceable seating together of the two members thereby insuring proper engagement of multiple-contact electrical connectors carried by the members. Upon further rotation of said cam cylinder in the direction for tightening the assembly, both the fixed and movable pins ride in the sloped portion of the helical slot, whereby the cam cylinder is forced axially of the elongated opening so as to urge the roller members mutually together as has been described. Thus, a single rotational motion of the cam cylinder achieves both a forced locked eating of the members and also a forced wedging of the contact portion of the first member in the recess of the second member. A reversed rotation of the cam cylinder causes a reversed sequence of action, thus mutually releasing the first and second members.

Brief description of the drawing FIGURE 1 is a perspective view of a preferred embodiment of the invention, looking downwardly toward the front and left side thereof, with the main frame and sub frame in separated position,

FIGURE 2 is a cross sectional view of the sub frame taken on the line 2-4 of FIGURE 1,

FIGURE 3 is a top view of the preferred embodiment, with the sub frame and main frame assembled but in unlocked condition;

FIGURE 4 is a partial rear view taken on the line 4-4 of FIGURE 3;

FIGURE 5 is a view the same as FIGURE 4, but with the assembly in partially locked position,

FIGURE 6 is a cross sectional view taken on the line 6-6 of FIGURE 5, and showing the assembly in fully locked position,

FIGURE 7 is a side view of a cam cylinder utilized in the preferred embodiment of the invention,

FIGURES 8 and 9 are development views of cam slots in the cam cylinder of FIGURE 7, showing actuation pins in different operative positions in the cam slots, and

FIGURE 10 is a perspective view of a hollow roller member used in the preferred embodiment.

Description of the preferred embodiment As shown best in FIGURE 1, the preferred embodi' ment of the invention comprises one or more sub frames 11 adapted for attachment into amain frame 12 provided with a plurality of pairs of oppositely disposed mutually facingparallel recesses 13, 14 adapted to receive opposite edge portions, 16, 17 of the sub frame 11 when it is slid into themain frame 12. Any desired numbers of pairs ofrecesses 13, 14 may be provided in themain frame 12, and numerousmain frames 12 may be attached together, in order to accommodate a desired number of sub frames 11. Themain frame 12 is shown as being provided with heat dissipating fins 18 in order to more readily dissipate heat conducted to the main frame from the sub frame 11. By way of example, the overall size of a sub frame 11 useful for carrying electronic circuitry such as is used in computers, may be approximately 12 inches long, 6 inches wide, and /2 inch thick. Themain frame 12 may be manufactured by machining therecesses 13 and 14, and coolingfins 18, into pieces of metal flat stock, and assembling pairs of these machined pieces in mutually facing parallel relationship by means of afront piece 21 andrear piece 22 attached by screws or other suitable means, or the unit may be made from one or more castings. Thewalls 23 between recesses 13, and thewalls 24 betweenrecesses 14, are provided with anoflset shoulder 26 and a notch .27, as shown, for the purpose of receiving a locking pin as will be described later.

The sub frame 11 is provided with one ormore recesses 31 having ledges 32 at the sides thereof containing one or more threadedopenings 33. Therecesses 31 are adapted to contain electronic circuits (not shown) carried by one or more metal sheets or strips which are attached to the sub frame 11 by means of screws threaded into theopenings 33, or by other suitable means for transferring heat from the electronic circuits to the metal sub frame 11.

The sub frame 11 is provided withcentering pins 36 adapted to enter centering openings 37provided in themain frame 12 for the purpose of insuring proper mating of multiple contactelectrical connectors 38, 39 carried respectively by the sub frame 11 and main frame 12 (refer to FIGURE 4). Each of theside portions 16 and 17 of the sub frame 11 is provided with anelongated opening 41 therein, extending substantially the entire length of the side portion. A plurality ofroller members 42 are positioned in theopening 41, in a staggered alternately offset manner, as best shown in FIGURE 2. Preferably theroller members 42 have a diameter equal to approximately /3 the dimension of the width of theopening 41. Preferably theroller members 42 comprise hollow metal cylinders, as shown in FIGURE 10, arranged on mutually parallel axes that are mutually perpendicular to the axis of theelongated opening 41 and to the thickness dimension of the sub frame 11.

The bottom end of the arrangement ofroller members 42 is supported by anadjustable screw 43, threaded into a threadedportion 44 near the lower end of each of-theside portions 16 and 17, and provided withslots 46 to accommodate an adjustment tool, theseslots 46 being reached by the adjustment tool via an access cut out 47 provided in each of theside portions 16 and 17.

Theelongated openings 41 are bounded along three sides thereof by theside portions 16 and 17, the fourth side thereof, which faces asidewall 23 or 24 betweenrecesses 14 or 13 of themain frame 12 when asssembled,

constituting aretainer plate 51 which fits partially into the elongated opening and which is resiliently urged against the assembly ofroller devices 42 by means ofwire spring 52 carried inslots 53 of the sub frame 11 and retained in place byretainer pins 54,theseretainer springs 52 extending into engagement againstshoulders 56 of theretainer plates 51 so as to urge these plates inwardly in theopenings 41 and against the assembly ofroller members 42. a

A pair of motion mechanisms, which are camdevices 61 in the preferred embodiment of the invention, are respectively positioned at the upper ends of theelongated openings 41 in theside portions 16, 17 of the sub frame 11.

Eachcam device 61 comprises an assembly of acam cylinder 62, anactuation lever 63 pivotally attached to thecam cylinder 62 at the upper end thereof, a take-upcompression spring 64 attached to thecam cylinder 62 at the bottom end thereof, and a fixedpositioning pin 66 and a movable floating lockingpin 67 arranged in a manner to be described. The sub frame 11 is provided withopenings 71 and 72 into which the two pivotedlevers 63 are respectively placed when the assembly isin the locked condition. Eachlever 63 is pivotally attached to the upper end of the associatedcam cylinder 62 means of apivot pin 73, so that thehandle 63 is pivotable about an axis lateral to that of thecam cylinder 62. By turning thelever 63, thecam cylinder 62 is caused to rotate, as will be described more fully. Thecompression spring 64 may be what is known in the art as a Belleville washer stacked spring, Le, a stack of Belleville washers, which are resilient and slightly conical'in shape, stacked in alternating orientation on aspring rod 76 having a retaining head 77 and passing through an opening in the lower end of thecam cylinder 62 and captivated thereto by means of a C-ring retaining washer 78, as best shown in FIGURE 2. I

Thecam cylinder 62 is provided with apair ofhelical slots 81 and 82, as best shown in FIGURES .7, 8 and 9. In FIGURES 8 and 9, thevertical axis 79 represents cam lift height in inches, and thehorizontal axis 80 represents cam rotation in degrees. Thehelical slots 81 and 82 are identical, and are angularly spaced 180 apart on thecam cylinder 62, the lower portions (approximately of cam rotation) 83 thereof being offset so as to have no slope. Theslots 81 and 82. extend a total angular peripheral distance of 490 in the preferred embodiment of the invention, and theupper portions 84 thereof are offset a short distance so as to have no slope, as shown. Adetent 86 is provided in each of the slots at the 310 position, as shown, for a purpose to be described later.

The fixedpin 66 is positioned in openings at opposite sides of the sub frame 11, and extends throughboththelical slots 81 and 82 of thecam cylinder 62. The floatingpin 67 extends outwardly of the frame 11 a short distance, and passes through an L-shapedslot 91 in a side-wall of the sub frame 11, and through bothhelical slots 81 and 82 of thecam cylinder 62 at a position approximately one-half revolution above the position of the fixed.pin 66. The floatingpin 67 is captivated by means of acylindrical plug 92 positioned within thehollow cam cylinder 62 and provided with an opening through which thepin 67 fits snugly.

The invention functions as follows. When the sub frame 11 andmain frame 12 are disassembled, as shown in FIGURE 1, thecam cylinders 62 have been turnedyby means of thelevers 63, so as to be in their'upmost-position, as shown in FIGURES 1, 2 and 4. In this position, the fixedpin 66 is at the zero degree or lower-most point on thecam slots 81 and 82, and the floating pin67 is at the 200 point, as shown in FIGURE '8. In this position, the floating pins 67 extend angularly with respect tothe sub frame 11, through the short leg portion of the-IL- shapedslot 91, as shown best in FIGURES 3 and 4. The

sub frame 11 is slid into a pair ofrecesses 13, 14 of themain frame 12, and the floating pins 67 pass closely by the offsetshoulders 26 of the recess sidewalls 23, 24, and respectively seat against thesidewalls 23 and 24 adjacent thenotches 27. In this position, the multiple contact electricall'connectors 38 and 39 have not reached engagement position. With thecylinder 62 in the aforesaid zero degree'or raised position, no pressure is exerted on the assembly ofroller members 42, and hence theretainer plate 51 is in its most recessed position in theelongated opening 41 in each of theside portions 16, 17 of the sub frame 1'1, and hence the sub frame 11 slides readily in the pair ofrecesses 13, 14.

Thelevers 63 are now rotated, manually, each through an angle of 310 in the directions indicated by the circular arrows 93, 94 (FIGURE 3) and then are placed downwardly into theopenings 71 and 72, respectively, thus completing the assembly procedure in a quick and simple manner/The aforesaid rotation of 310 of thecam cylinder 62 by means of thelevers 63 causes the following sequence of actions to occur. During the first twenty' degrees of cam cylinder rotation, the floatingpin 67 moves sideways into thenotch 27 of themain frame 12, as shown in FIGURE 5, at which point the fixedpin 66 is at the twenty degree point asindicated by numeral 66a in FIGURE 8, the floatingpin 67 still being at the 200 point. During the remainder of the cam rotation, the'fixed' pin and floatingpin 67 are-in vertical alignmentf'a'nd are 180 apart in each of thecam slots 81 and82.'

As'the cam cylinder 62' is rotated further, from the point'to th'90 point, the floatingpin 67, which now is captivated in fixed position by thenotch 27, causes thecam slots 81 and 82 to force downwardly on the fixedpin 66 thereby forcing the subframe 11 downwardly into seated position in theframe 12, thus forcing the multiple contactelectrical connectors 38 and 39 together. In FIG- URE 5, which represents the apparatus with the cam mechanism at the 90 point, with-the fixedpin 66 and floatingpin 67 at the 90 and 270 points, respectively, as shown in FIGURE 9, the sub frame 11 has been forced downwardly into themain frame 12 as compared with the position shown in FIGURE 4.- This cam forcing of the multiple contactelectrical connectors 38 and 39 together is important, because, due to the multiplicity of contacts needed to accommodate electrical connections to the numerous circuits carried by the sub frame 11, it would not be feasible to rely on a person manually forcing the sub frame 11 into seated position in the main frame Beginning with the 90 cam rotation point, as shown in FIGURE 9, the fixedpin 66 and floatingpin 67 remain relatively fixed in position with respect to each other, and simultaneously ride in the slopedhelical slots 81 and 82. Since these pins are in fixed position with respect to theframes 11 and 12, further. rotation of thecam cylinder 62 causes the cam cylinder to turn downwardly with respect to the elongated opening '41 in each of theside portions 16 and 17 of the subframe 11, thus urging thespring assembly 64 downwardly against the arrangement ofroller devices 42, thereby. expanding the roller arangement laterally and forcing ,thepressure retainer plate 51 outwardly against theadjacent sidewalls 23 and 24 in themain frame 12. Thus, the sub frame becomes tightly wedged into therecesses 13 and 14, at or prior to the full 310 rotation of thecam cylinders 62, at which point the fixedpin 66 engages thedetent 86 in theslots 81 and 82 as indicated by numeral 66 in FIGURE 9, and at which point the floating pin is at theupper position 67 in theslots 81 and 82. With the fixed pin in thedetent 86 as indicated at numeral 66', there is a clicking positioning of thelevers 63 over their respective frame opening 71 and 72, whereupon these levers are readily placed downwardly into these openings so as to be flush with the top of sub frame 11 and hence out of the way, it being noted that for at least a portion of the rotation of thelevers 63 they must be pivoted slightly upwardly in order to properly rotate thecam cylinders 62 into the sub frame 11. Thespring arrangement 64 functions to take up any excess motion in the downward motion of thecam cylinder 62 with respect to the fully wedged position of the sub frame 11 in themain frame 12.

The aforesaid wedging of the sub frame 11 in therecesses 13 and 14 of themain frame 12, provides both good electrical (such as electrical ground) connection, and also provides for uniform heat conduction contact between the sub frame 11 andmain frame 12, all along the length of theside portions 16 and 17 of the sub frame 11, thus effectively conducting heat generated by electrical circuits carried by the sub frame 11, to themain frame 12 where it is further dissipated into surrounding space with the aid of theheat radiating fins 18. The adjustment screws 43 are adjusted when necessary so as to assure proper functioning of the assembly ofrollers 42 to exert proper outward pressure and motion on thepressure plate 51. The main heat conducting path, it may be noted, is not through thepressure plates 51, but rather through the opposite sides of theend portions 16 and 17 to theadjacent sidewalls 23, 24 of themain frame 12.

It will be readily realized that the invention solves the prior problems that have been described above, and provides an arrangement whereby a first member can be securely attached to a second member quickly and easily by merely sliding them together, and turning one or more levers or actuating other means for turning the cam cylinders, or otherwise exerting force downwardly on the arrangement ofrollers 42. Furthermore, this quick assembly arrangement provides sequential functions of forcing the sub frame member into seated position with respect to the main frame member, and then wedges the members together along one or more elongated portions there of, thus providing effective electrical, mechanical, and thermal contact therebetween. To disassemble the arrangement, a person simply lifts thelevers 63 out of theiropenings 71 and 72, and rotates them in the reverse direction as for locking the assembly, whereby in one simple motion of the levers the assembly is released from the wedging action in therecesses 13 and 14, and is forced upwardly thereby separating the multiple contactelectrical connectors 38 and 39, whereupon the sub frame 11 is easily slid out of themain frame 12.

As has been described, theroller members 42 preferably comprise hollow metal cylinders as shown in FIG- URE 10; however, they may comprise solid cylinders or spherical balls if desired, the cylinders being preferred because of greater contact area mutually between them. As a further feature of the invention, the hollow roller cylinders are made sufiiciently resilient so as to provide some or all of the aforesaid motion takeup as an aid to or in lieu of the functioning of thetakeup compression spring 64.

While a preferred embodiment of the invention has been shown and described,'various other embodiments and modifications thereof will become apparent to persons skilled in the art, and will fall within the scope of invention as defined in the following claims.

I claim:

1. An arrangement for pressing first and second members together at elongated contact areas thereof, wherein the improvement comprises a plurality of roller members arranged in an elongated staggered manner alongside said contact areas, and means for applying force axially on said elongated arrangement of roller members thereby to cause said roller members to exert a lateral force for pressing said first and second members together at said elongated contact areas thereof.

2. An arrangement as claimed in claim 1, in which said first member is provided'with an elongated opening alongside said elongated contact areas, said elongated arrangement of roller members being positioned in said elongated opening, and including an elongated pressure plate positioned in said elongated opening and means for urging said pressure plate toward said arrangement of roller members so that the outer surface of said pressure plate normally is substantially flush with the surrounding surface of said first member, whereby said axial force on the roller members causes them to force said pressure plate outwardly with respect to said elongated opening.

3. An arrangement as claimed in claim 1, in which said means for applying force axially includes means for imparting motion over a predetermined distance along the axis of said elongated arrangement of roller members, and further including a compression spring take-up means interposed in said combination of roller members and means for applying force, so as to take up any excess of said motion thus providing consistent pressure over said elongated contact areas.

4. An arrangement as claimed in claim 3, in which said take-up means comprises said roller members, said roller members being in the form of hollow cylinders made from resilient material so as to be compressible for providing said take-up of any excess motion.

5. An arrangement for removably attaching a sub frame to a main frame, said sub frame being adapted to carry electrical circuitry and said main frame being provided with at least one elongated recess adapted to receive an elongated side portion of the sub frame when said sub frame is slid into said main frame, wherein the improvement comprises a plurality of roller members arranged in an elongated staggered manner along said elongated side portion, and means for applying force axially on said elongated arrangement of roller members thereby to cause said roller members to exert a lateral force for bringing said side portion and said recess into mutual contact substantially along the lengths thereof.

6. An arrangement as claimed in claim 5, in which said elongated side portion of the sub frame is provided with an elongated opening extending therealong, an elongated dimension of said opening being exposed along a side of said sub frame adjacent to and alongside said elongated recess of the main frame when said frames are assembled together, said elongated arrangement of roller 8. An arrangement as claimed in claim 7, in which said take-up means comprises said roller members, said roller members being in the form of hollow cylinders made from resilient material so as to be compressible for providing said take-up of any excess motion.

9. An arrangementas claimed in claim 6, in which said means for applying force axially on the elongated arrangement of roller members comprises a cam cylinder positioned in said'sub frame near an end of and substantially in axial alignment with said elongated opening, said cam cylinder being rotatable between limits defined as the locked and unlocked conditions of said frame assembly and being provided with at least one helical slot having an offset region of zero slope, a fixed pin carried by said sub frame and extending into said helical slot at said offset region thereof when said cam cylinder is at said unlocked limit of rotation, an opening through the wall of said sub frame adjacent said cam cylinder, a floating pin extend-ing into said helical slot and extending through said last-named opening externally of said sub frame, said last-named opening being dimensioned to permit limited rotation of said floating pin with rotation of the cam cylinder, a notch -in said main frame adapted to receive said floating pin when said cam cylinder is rotated from the unlockd condition whereby the action of the fixed pin riding in said offset region of the rotating members being positioned in said elongated opening, and

including an elongated pressure plate positioned in said elongated opening and means for urging said pressure plate toward said arrangement of roller members so that the outer surface of said pressure plate is substantially flush with said side of the sub frame, whereby said axial force on the roller members causes them to force said pressure plate outwardly with respect to said elongated opening and against a surface of said elongated recess thereby wedging together said sub frame and said main farme.

7. An assembly as claimed in claim 6, in which said means for applying force axially includes means for imparting motion over a predetermined distance along the axis of said elongated arrangement of roller members, and further including a compression spring take-up means interposed in said combination of roller members and means for applying force, so as to take up any exces of said motion thus providing consistent pressure of said wedging together of the sub frame and main frame.

slot and said floating pin riding in the rotating helical slot forces said sub frame to move into seating position with respect to said main frame until the fixed pin reaches an end of said offset region, whereupon with continuing rotation of the cam cylinder said fixed pin and said floating pin ride simultaneously in the helical slot thus causing the cam cylinder to screw toward said assembly of roller members thereby applying said force axially thereto.

10. An assembly as claimed in claim 9, in which said cam cylinder is so dimensioned that the upper portion thereof extends from said sub frame when at said unlocked limit and the top thereof is substantially flush with the surface of said sub frame when at said locked limit, and including an actuation lever pivotally attached to said cam cylinder at the top thereof and oriented to lie over the top surface of said sub frame when the cam cylinder is at said locked limit, a detent in said helical slot to receive one of said pins at said locked limit, and an opening in the top surface of said sub frame adapted to receive said pivoted lever when the assembly is in locked condition.

References Cited UNITED STATES PATENTS 9/ 1949 Andersson. 6/1966 Arguin et al.

OTHER REFERENCES IBM Technical Disclosure Bulletin, vol. 6, No. 6, November 1963,page 39.

U.S. Cl. X.R.

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