US3104897A - Berger - Google Patents

Description

Sept..24, 1963 K. BERGER 3,104,897

' ELECTRIC SWIVEL CONNECTOR Filed June 29, 1960 2 Sheets-Sheet 1 ,7 INV EN TOR. KOtF/YEL 5593a BY 544; an: I I

Sept. 24, 1963 K. BERGER ELECTRIC SWIVEL CONNECTOR 2 Sheets-Sheet 2 Filed June 29, 1960 INVENTOR.

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ATTORNEYS 3,164,897 ELECTRIC SWIVEL CGNNECTOR Kernel Berger, Kew Gardens, NX. Berger Machine Products Inc, 74-16 Grand Ave, Maspeth, Long Island, NY.)

Filed June 29, 1960, Ser. No. 39,599 1 Clair (Cl. 285-166) This invention relates to an electrical swivel connector.

In general, said connectors are of two kinds, one being the so-called ball type which is occasionally referred to hereinafter as an unrestricted connector, and the other the so-called restricted connector. The fundamental difference between these is that in an unrestricted, i.e. ball, connector, one member can experience rotational movement with respect to another member about any one of three intersecting rectangular axes, that is to say, true swiveling movement, whereas in the restricted connector, one member can experience rotational movement with respect to the other about only a single transverse axis, an additional mode of rotation being provided by a second joint that permits rotation about an axis running longitudinally of the connector. Because of the compound movement permitted by the two joints, a restricted connector has come to be known as a swivel connector, although this term is mechanically incorrect.

For various reasons, although ball connectors are less expensive, simpler and more compact, the trade prefers restricted, i.e. swivel connectors. However, a certain basic difliculty arises in connection with the latter. The members which experience mutual relative movement about the single axis have connecting bores for passage of a wire, so that when the angle of rotation approaches 90, the end of the bore in one of the members will be exposed. Since this is unsightly and otherwise undesirable, heretofore various elaborate mechanical arrangements have been devised to permit therequisite 90 mutual rotation to be experienced without exposing said bore. Despite the comparatively complex and cumbersome structure that ensued, such restricted connectors have found favor in the public eye.

It is an object of my invention to provide an improved and simplified restricted (swivel) connector which permits the desired 90 rotation to take place without the provision of any additional mechanical part for concealing the aforesaid bore.

As note da-bove, in previous restricted (swivel) connectors, it has been customary to provide the needed second mode of rotation by a second joint at an end of the connector remote from the restricted joint. It is another object of my invention to modify the aforesaid second joint whereby to allow a restricted (swivel) connector to experience 90 rotation without the utilization of an extra part at the restricted joint.

It is a further object of my invention to provide an electric swivel connector of the character described, which is durable and inexpensive, and which lends itself to mass production.

Other objects of my invention in part will be obvious and in part will be pointed out hereinafter.

My invention accordingly consists in the features of construction, combinations of elements and arrangements of parts, which will be exemplified in the electric fitting hereinafter described, and of which the scope of application will be indicated in the appended claims.

In the accompanying drawings in which is shown one of the various possible embodiments of my invention,

FIG. 1 is a side elevational view in partial section of an electric swivel connector constructed in accordance with my present invention and having the parts thereof arranged in alignment;

FIG. 2 is a side view of said connector, showing in full 3',ld4,897 Patented Sept. 24, 1953 2 lines the parts rearranged to swing 90 to the left, and in dot-and-dash lines the parts rearranged to swing 90 to the right;

FIG. 3 is a top view of said connector, showing in full lines the parts rearranged to swing 90 to the left, and in dot-and-dash lines the parts similarly arranged but displaced approximately 30 in azimuth;

FIG. 4 is a front elevational view to a reduced scale of said swivel connector; and

FIG. 5 is an exploded perspective view of the swivel connector.

Referring now in detail to the drawings, the reference numeral .lti denotes my new electric swivel connector. Said connector includes anelongated casing 12 of tubular, i.e., hollow, open-ended, contour. More particularly, the casing is formed adjacent its lower end to the shape of acylindrical portion 14, the axis of symmetry of which is coincident with the longitudinal axis of the casing. The lower edge of the cylindrical portion is inturned to provide aflange 16 that defines a large constricted bottom opening 18 of somewhat smaller diameter than that of the cylindrical portion.

Above thecylindrical portion 14 thecasing 12 flares outwardly at a comparatively small angle, e.g., in the neighborhood of 8, providing thereby aconoidal part 20. The top of the conoidal part runs smoothly into an upper mutilate-dcylindrical portion 22. Saidportion 22 includes two curved sections 24 (see FIG. 5) joined byparallel flats 26. The curved sections are parts of a true cylinder and would conjointly define a single true cylinder except for the interruption, i.e., mutilation, of theparallel flats 26. For design appearance, the flats may be continued down theconoidal portion 20, tapering in width as they approach the lowercylindrical portion 14.

The uppercylindrical portion 22 mounts at its top end an upperspherical segment 28. Said spherical segment is a smooth continuation of :both thecurved sections 24 and theflats 26. Thespherical segment 28 terminates at a constricted top opening 34 of lesser diameter than the uppercylindrical portion 22, so that both the top and bottom ends of the casing '12 are constricted and thereby will captively retain therein objects of slightly larger diameter than said ends.

it will be appreciated that all of the sundry parts of the casing jointly comprise a single piece, the casing prefer-, ably constituting a one-piece tube of sheet metal which has been appropriately shaped by suitable dies to assume the configuration described. It also should be mentioned at this point that such con-figuration is not entirely imparted until the last stage in the assembly of the electric swivel connector. More particularly, theflange 16 is provided before assembly and thespherical segment 28 is spun to its final form as the last stage in assembly, having theretofore constituted simply an extension of thecylindrical portions 22. This operation will be described in somewhat greater detail hereinafter.

The electric swivel connector 10- further includes aball 32 which may, if desired, constitute, as illustrated, a die-casting, although it is within the scope of my invention to manufacture the same by turning or from sheet metal by a series of forming operations. Said ball includes a hollowspherical portion 34 from one sideof which extends, preferably in one piece therewith, a threadedtubular shank 36, aflange 38 being provided at the base of the shank where it joins the spherical portion. The flange is formed with a pair of diametrically opposed parallel flats it? to assist in coupling the shank to a threaded female part. The bottom of the spherical portion is formed with alarge opening 42 for passage of a wire extending through the connector. Thespherical portion 34 includes a pair of diametrically opposedflats 44 at the ends of 3, major diameter of the ball perpendicular to the longitudinal axis of theshank 36. Said ball has a diameter substantially equal to the diameter of the internal surface of the upper spherical segment 2%.

The islooated within the casing '12 at the upper end thereof, and is seated in thespherical segment 28 with the threadedshank 36, theflange 38, and the adjacent part of thespherical portion 34 protruding from the top opening 34) of the casing, and with theflats 44 rotatably resting against the inner surfaces of theflats 26. It will be observed that at diametrically opposite edges of the upper opening 3%, the upperspherical segment 28 is deeply notched as at 46. The location of these notches with respect to the center of thespherical portion 34 is such that theneck 48 between theflange 38 and the spherical portion will abut said notches to confine the extremes of movements of theshank 36 with respect to the casing to an angular range less than 180. More particularly, this range is sufiiciently below 180", e.g. about 90, to prevent theopening 42 from being exposed as the ball turns. It further will be observed that the cooperation between theflats 26 and 44 restricts rotation of the ball with respect to the casing to turning movement about a single axis that is perpendicular to the longitudinal axis of theshank 36, is perpendicular to theflats 26, 44, is coincident with a major axis of thespherical portion 34, and is substantially centered in theflats 44, As soon will be seen, theball 32 is biased against the upper end of the casing, so that it can turn, subject to stop limits, in the manner aforesaid.

The portion of theball 32 located within thecasing 12 rests on an open-ended thimble 50. Said thimble is in the form of a sheet metal cup, the major portion of which constitutes acylindrical side wall 52 having an out-turned annular sphericallysegmental flange 54 at its upper end. Preferably the flange is shaped to match the curvature of the spherical portion 34', so that there is a nice fit between these parts. Adjacent its base the thimble is provided with an in-turnedshoulder 56 running into a shorttubular projection 58 co-am'al with theside wall 52,

The biasing action above described is furnished by an open-endedhelical compression spring 60, the upper end of which telescopically receives the shorttubular projection 58. It is apparent from the dnawings that thethimble 50 is located within thecasing 12, and that thespring 60 which biases the thimble against the ball, and the ball in turn against the constricted upper end of the casing, likewise is located internally of the casing.

I further provide an open-ended ferrule 62 constituting atubular sleeve 64 having a frusto-conical outwardly extendingflange 66 at its lower end. Thesleeve 64 is of proper diameter to telescopically fit within the lower end of the spring '60. Theflange 66 terminates in a large diametershort tube 68. The lower end of thespring 60 telescopically receives thetubular sleeve 64 and bears against theflange 66.

Pursuant to my invention, I provide an unrestricted type joint 70 at the lower end of the casing, that is to say, a joint which permits rotation about three intersecting rectangular axes, in other words, a true swivel joint. This joint does have a diflerent kind of restriction, which I will refer to hereinatter as a limitation, in that Iotation about two of these axes is limited to approximately 45 to either side of center, i.e., about 90 through center, and about the third axis to less than 360 'I obtain the desired action by utilizing a second ball '72 which, desirably, is manufactured in the same manner as thefirst ball 32, that is to say, preferably by diecasting, although optionally by any other mode or fabrication. Theball 72 includes a hollowspherical portion 74 from which there extends a threadedtubular shank 76 provided with the usual shoulder 73, the latter being connected to the spherical portion at aneck 80. The top of the spherical portion is formed with alarge opening 82 for passage of a Wire extending through the joint. For a purpose which soon will be apparent, I mutilate the surface of thespherical portion 74 along a great circle zone running in a general direct-ion from theopening 82 7 toward theshank 76. This mutilation may take the form of a raised ridge, a fiat or a groove, and herein constitutes agroove 84 lying on a great circle of thespherical portion 74. The upper end of the groove stops short of theopening 82. The lower end of the groove stops short of theneck 80.

The trustoconical flange 66 seats thespherical portion 74 of theball 72 and said flange bears against said spherical portion under the force exerted by the spring 6t), that is to say, said spring urges the twoballs 32, 72 I to swivel about a point on this axis at the center of thespherical portion 74. Theferrule 62 includes an internally protrudinglug 36 the surface whereof is shaped to ride smoothly in the groove 84.- The lug is located on thetube 68 at any point in a plane perpendicular to the longitudinal axis of the casing and intersecting thespherical portion 74 along a great circle so that it is disposed at an end of a major diameter of thespherical portion 74 of'the lower ball. Theferrule 62 additionally is provided with an erectrotating stop arm 38 which rides along, i.e., adjacent, the inner surface of thecylindrical portion 14 of the casing part. Said portion has .an inwardlyprotuberant boss 90 in the path swept by thearm 88.

Before assembly of the parts, thecasing 12 has an unconstricted top end, that is to say, the upperspherical segment 28 has not yet been formed but the flange-16 already has been provided. At this time the upper end of the casing constitutes an unmodified continuation of the uppercylindrical portion 22, including thecurved sections 24 and theflats 26. The various parts are inserted into the casing in the order shown in FIG. 1, that is to say, theball 72 is seated in theopening 18 with theshank 76,flange 78, neck and adjacent part of thespherical portion 74 protruding from the open lower end of the casing.

Next, theferrule 62 is placed atop the ball with thelug 86 riding in thegroove 84 and thespring 60 is seated on thesleeve 64 of the ferrule. Thetube 68 is located between theball 72 and the cylindrical portion of the casing so that the ball is rotatably encaged between theferrule 62 and the lower end of the casing. Next thethimble 50 is set on thespring 60, with thetubular projection 58 inside the spring. Finally, theball 32 is seated on thethimble 54 At this time, due to the lengths of the sundry parts in a direction parallel to the longitudinal axis of the casing, theball 32 will be too high in the casing. Accordingly, thespring 60 is compressed by forcing theball 32 downwardly until it is located at its proper position within the casing. Then, with suitable spinning machinery, thespherical segment 28 is formed, thereby constricting the upper end of the casing and captively locking all of the parts therein. Spinning theupper segment 28 provides 7 a spherical seat for theupper ball 32. Theflange 16 furnishes a swivel seat for thelower ball 72.

When the twoballs 32, 72 are angularly arranged so that theirrespective shanks 36, 76 are co-axial, as shown in FIG. 1, an electric wire can he threaded in a straight line through theconnector 10. Thus, referring to FIG.

1, it will be seen, reading from top to bottom, that aligned straight openings are formed in theball 32, thethimble 50, thespring 60, theferrule 62, and theball 72.

Theupper ball 32 is capable of restricted movement, that is to say, movement about a single axis, perpendicular to the longitudinal axis of the casing between an inline position (the position shown in FIG. 1) and two extreme angular positions (shown in FIG. 2), in one of which the .neck 48 will abut one of thenotches 46, in the other of which the neck will abut the opposite notch. As mentioned earlier, the notches are so arranged that in neither of these extreme positions will theopening 42 be exposed. However, because of this limitation of movement about a single perpendicular axis, theupper ball 32 is not capable of swinging up to 90 to both sides with respect to the longitudinal axis of the casing, the actual extremes of movements being about 45 as indicated in FIG. 2. It is in order to compensate for this limitation that I have provided in connection with the restricted joint at the upper end of the casing, an unrestricted second joint, albeit of limited movement, at the lower end of the casing.

At the lower end of the casing, theball 72 can experience several modes of movement, all of which are limited, that is to say, the ball has unrestricted (true swivelling) limited movement. Thus, said ball is able to turn about one horizontal axis (assuming the connector to have its longitudinal axis vertically oriented), this being the axis perpendicular to the plane of thediametrical groove 84. When this turning movement is experienced, thelug 86 rides in thegroove 84. Additionally, the ball can turn about a second horizontal axis at right angles to and intersecting the foregoing *axis, that is to say, about a horizontal axis running from thelug 86 to the longitudinal axis of the casing. Such movement is permissible because thelug 86 is loocated to lie approximately at the end of a major diameter of theball 72. Furthermore, the ball can turn about an axis coincident with the longitudinal axis of the casing. This latter movement is accompanied by movement of theferrule 62 to which the ball is keyed by the lug and groove. Such latter turning about the axis of the casing causes thestop arm 88 to swing about the inside of the casing.

It now will be apparent that movement of thelower ball 72 with respect to the casing can take place about three intersecting axes and therefore is of the so-ca-lled unrestricted type. Although the angular movement is unrestricted, it is limited in extent to prevent cutting of the wire which extends through the lower joint, twisting of said wire, or exposure of theopening 82. Movement of theball 72 with respect to either of the two horizontal axes above described is limited by abutment of theneck 80 against the edge of theopening 18. Additionally, rotation of the ball about the horizontal axis perpendicular to the plane of thegroove 84 is limited by abutment of thelug 86 against the shoulders at the ends of the groove. Rotation of the ball about the longitudi nal axis of the casing is limited by abutment of thestop arm 88 against theboss 90.

The parts are so dimensioned that theupper ball 32 can swing about 45 to either side of the longitudinal axis of the casing, and so that thelower ball 72 likewise can turn about 45 to either side of the longitudinal axis of the casing. These two angles are complemental, i.e., add up to 90, so that if both balls are turned in the same direction to their extreme limits, the longitudinal axis of theshank 36 will be perpendicular to the longitudinal axis of theshank 76, as illustrated in full lines in FIG. 2. If it is desired to swing theupper shank 36 to its diametrically opposed position, as shown in dot-and-dash lines in FIG. 2, the two balls are swung to their opposite extreme limits, or the casing is turned about the vertical axis of thelower ball 72, this latter motion being illustrated in FIG. 3. It will be appreciated by those skilled in the art that the limitation upon the lastmentioned movement, by abutment of the stop arm and boss, will prevent the wire that passes through the connection from being twisted to the point of breaking.

It thus will be seen that I have provided an electric swivel connector which achieves the various objects of my invention, and is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein described orshown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

An electric swivel connector comprising an open-ended hollow elongated casing having seats at opposite ends thereof, said casing having a pair of diametrically opposed flats near one of the seats and a cylindrical portion near the other seat, the cylindrical portion having an axis coincident with the longitudinal axis of the casing, a first hollow open-ended ball having diametrically opposed flats engaging the flats in the casing, said ball being seated in the seat near the flats in the casing whereby said first ball is mounted in said casing for rotation relative thereto only about a single axis transverse to the length of the casing, said ball having a shank extending therefrom and protruding from said casing to limit such rotation of: the ball about said single axis to an are less than 180, a second hollow open-ended ball, a tubular member rotatable in the cylindrical portion of the casing, the second ball being seated against the second seat of the casing, cooperating means in the second ball and tubular member for limiting rotation of the second ball relative to the tubular member to an axis transverse to the length of the casing, whereby said second ball is mounted in the casing for rotation about three rectangular axes one of which is parallel to the length of the casing, said second ball having -a shank extending therefrom and protruding from said casing to limit such rotation of the second ball about two of said rectangular axes other than the parallel axis to an are less than 180, means to limit rotation of the tubular member with respect to the casing to an arc exceeding 180 and less than 360 whereby rotation of the second ball relative to the casing about the parallel axis is similarly limited, and hollow open-ended spring means forcing said balls apart. 3

References Cited in the file of this patent UNITED STATES PATENTS 1,665,810 Gillick Apr. 10, 1928 1,927,703 Glowacki Sept. 19, 1933 2,862,730 Berger Dec. 2, 1958 2,887,329 Blakely May 19, 1959 3,012,798 Berger Dec. 12, 1961

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