US3132912A - Electrical connectors - Google Patents

Description

May 12, 1964 M. FRIEDMAN 3,132,912

ELECTRICAL CONNECTORS Filed Nov. 29, 1960 2 Sheets-Sheet 1 INVENTOR.

MITCHELL FRIEDMAN May 12, 1964 M. FRIEDMAN ELECTRICAL CONNECTORS 2 Sheets-Sheet 2 Filed Nov. 29, 1960 FIG-ll IN V EN TOR.

MAN

MITCHE? FRI United States Patent 3,132,912 ELF. TREQAL CQNNEQTGRS Mite ell Friedman, iielleville, NJ. (Viewland Drive, RG. Box .51, Yorktown Heights, N.Y.) Filed Nov. 29, 196i), Ser. No. 72,514) 5 Claims. (Cl. 339-64) The invention relates to improvements in miniature electrical connectors of the multiple pin and socket type.

In the manufacture of multiple pin and socket connectors of miniature form, it has been the practice (as disclosed, for example, in De lur et al. 2,736,870, granted February 28, 1956) to retain the pins and sockets in assembled relationship with the block or body of electrically insulating material by means of spring lock washers or snap rings. The insulating body is molded with a plurality of laterally spaced cavities each of which have a communicating bore of smaller diameter than the diameter of the cavity. The bore extends to the exterior side of the body opposite the side thereof which engages the body of the other connector half when the connector halves are coupled. An internal shoulder is provided in the body at the juncture of each cavity and communicating bore. The pin and socket contacts, each of which have a rearwardly extending shank, are positioned in the cavities with the shanks extending through the bore and exteriorly of the insulating body. The contacts are each provided with a flange or a portion having a diameter larger than the diameter of the shank for engagement with the internal shoulder. The shank is made sufiiciently long so that the free end thereof may be provided with a solder cup portion to permit the connection of a wire or conductor thereto. The solder cup portion is formed by a drilling and milling operation.

In order to retain the pins and sockets in assembled relationship with their respective insulating bodies, an annular groove is cut or milled in the shank of each con tact at the area thereof adjoining the side of the insulating body. The assembly is completed by securing a metal lock washer or snap ring in the groove of each contacts shank. The lock washer, of course, has an outer diameter which is greater than both the diameter or" the bore through which the shank extends and the diameter of the main or ungrooved portion of the shank.

This commercial and well known method of manufacture has a number of limitations and disadvantages. In miniature multiple contact electrical connectors, the shanks of the contacts may have a diameter on the order of 0.040 inch, or less. It will be apparent that the reduction in cross-section, resulting from cutting or milling an annular groove therein, greatly reduces the mechanical strength of the contact, because the shank is of such small cross-section initially.

Secondly, it is desirable that the lateral spacing between contacts be kept as large as possible in order that voltage breakdown between adjacent contacts be kept to a minimum. The metal lock washers, which of necessity have an outer diameter greater than the diameter of the contacts shank-s, increase the effective diameter of the shanks, thereby reducing the surface leakage path between adjacent contacts,

Thirdly, drilling and milling the shank to form the solder cup portion thereof is very painstaking and expensive. This will be appreciated when it is considered how very small are the diameters of the contact shanks in miniature form electrical connectors.

Fourthly, the prior art technique, utilizing metal lock washers to retain the contacts in assembled relationship with their respective insulating bodies, restricts the size of the wire which may be connected to the contacts. This is due to the limitation imposed by the small diameter or each contact shank. Such small diameter, and hence the diameter of solder cup portion, is restricted by the necessity to minimize voltage breakdown between adjacent contacts, the effective lateral spacing of which is reduced by the retaining, conductive lock Washers.

In accordance with my invention, a miniature electrical connector of the multiple pin and socket type is provided which eliminates the necessity for grooving the shanks of the contacts, thereby eliminating the eiiort and expense attending this operation; also, the resulting reduction in mechanical strength of the piece is obviated. The use of lock washers is done away with. The surface leakage paths between adjacent contacts are increased to increase the resistance to voltage breakdown. The secondary drilling and milling operations to form the solder cup portions at the ends of the shanks is eliminated, together with the attendant expense. With pin and socket contacts of given and necessarily small size, larger wires may be connected to the contacts than permitted by the aforementioned prior art technique.

In accordance with another aspect of my invention, the insulating bodies for supporting the pin and socket contacts are constructed to permit the coupled connector halves to be mounted in a manner to prevent their separation, while allowing the connector to be readily disengaged irom the mounting means when it is desired to disconnect the coupled connector halves. Accordingly, the invention is directed to retainer means for securing the connector halves in connected, mating engagement, while permitting the coupled connector parts to be readily removed from the retainer means when it is desired to uncouple or disconnect the parts. Also, the invention is directed to retaining or mounting means for one of the connector halves of the invention.

These, and other advantages and improved results will be apparent from the following detailed description of a preferred embodiment of the invention, taken in conjunction with the drawings, in which:

FIG. 1 is a side elevational view showing an electrical connector of the multiple pin and socket type embodying the structure or" the invention, the connector halves being shown in uncoupled relationship;

FIG. 2 is a View, greatly enlarged, showing one of the pin contacts in assembled relationship with the insulating body prior to their permanent connection to one another, the insulating body being shown in cross-section and the contact in elevation;

FIG. 3 is a perspective view of a member adapted both to retain a contact (pin or socket) in assembled relationship with the insulating body and to provide means for connecting a wire to the contact;

FIG. 4 illustrates the member of FIG. 3, serving to permanently connect the assembled contact and insulating body as shown in FIG. 2;

FIG. 5 is a view similar to FIG. 4, but illustrating the assembled and retained relationship orone of the socket contacts with respect to its insulating body;

FIG. 6 is a perspective view of another form of member affording the combined means for retaining a contact in permanently connected relationship with respect to the insulating body and for connecting a wire to the contact; 7

FIG. 7 is a view showing a socket contact secured to the insulating body by the member shown in FIG. 6, this view also illustrating a modified form of socket contact and a corresponding modification of the insulating body for assembly therewith;

FIG. 8 is a view similar to FIG. 6, showing a pin contact cooperable with the socket contact of FIG. 7 in assembled and connected relationship with its insulating body;

FIG. 9 is a perspective view of still another form of member affording combined means for retaining a contact in assembled relationship with the insulating body and providing means for conveying current from a wire to the contact;

FIG. is a side elevational view, partly broken away and in section, illustrating the connector of the invention with the halves thereof in coupled relationship and mounted to prevent their separation;

FIG. 11 is a perspective view of the connector mounting means shown in FIG. 10;

FIG. 12 is a perspective view, partly broken away and in section, illustrating another form of mounting means for the connector of the invention;

FIG. 13 illustrates the connector mounting means of FIG. 12 in a front-of-panel arrangement; and

FIG. 14 shows the connector mounting means of FIG. 12 in a behind-the-panel arrangement.

Referring to FIGS. 1 to 5, an electrical connector made in accordance with the invention comprises a body A and a body B. The bodies A and B are molded of suitable di-electric or electrically insulating material. The insulating body A is molded with a plurality of laterally spaced cavities or Wells 10, one of which is shown in FIG. 2; the body B is molded with a plurality of correspondingly spaced cavities 12, one of which is shown in FIG. 5. The number of spaced cavities correspond to the number of contacts (pins and sockets) which the connector is to provide, and as is common in the art, the cavities may be spaced from one another and located to provide the desired orientation for mating connection of the contacts, and connector halves, in only one and proper way. Each cavity 19 has a bore 14 in communication therewith. The bore is of a lesser diameter than the diameter of the cavity, thereby providing an internal shoulder 16. Simi larly, each cavity 12 in the body B is provided with a communicating bore 18 of smaller diameter to thereby provide an internal shoulder 20. The bores are in communication with the exterior of the insulating bodies. If desired, the bodies may be molded with a short, hol low external extension or boss, designated 22 in FIG. 2 and 24 in FIG. 5, surrounding the respective bores.

As shown in FIG. 1, the insulating body A is molded to provide an external flange 25. Similarly, the body B is provided with an external flange 25. Also, the bodies are each provided with a lug Z7, 27', each lug being located rearwardly of its respective flange. Preferably, the bodies A and B are molded to provide a cylindrical external outline. The purposes and functions of these flanges and lugs will be subsequently described.

As shown in FIG. 2, each pin contact C has a front portion 26, the free exposed end 28 of which is adapted for electrical connection to a mating female or socket portion. Rearwardly of the portion 26, the contact has a portion 30 of enlarged diameter, such portion being of a diameter slightly less than the diameter of the cavity 10 in which it is seated. The enlarged port-ion of the pin contact provides a shoulder 32 facing the internal shoulder 16 formed in the insulating body. Rearwardly of the enlarged portion 30, the pin contact is provided with a shank 34 of reduced diameter which extends through the bore 14 with a slight amount of clearance.

Correspondingly, and as shown in FIG. 5, each socket contact D, comprises a front socket portion 36, here shown to be of the split type, having a maximum diameter slightly less than the diameter of the cavity 12. The rear end of the socket portion provides a shoulder 38 facing the internal shoulder 20 of the insulating body. Rearwardly of the socket portion, the contact is provided with a shank 40' of reduced diameter which extends through the bore 18 with a slight amount of clearance.

The pin and socket shanks 34 and 4b are of a length to protrude but a short distance beyond their respective insulating bodies; each shank is of a shorter length than required when the end portion thereof is drilled to furnish a solder cup portion. In accordance with the invention,

the solder cup or means to connect a wire to the contact is supplied by the means which serves to retain the contact in secured relationship to the insulating body.

With a plurality of pin contacts C assembled with the insulating body A, each contact is secured to the insulating body by means of a sleeve-like member E. In the embodiment of the invention shown in FIG. 3, the member E is in the form of a short, hollow sleeve or tube. In fact, the sleeve is formed by severing sections from continuous length tubing. One end of each section or sleeve preferably is cut or scarfed to enlarge the opening to the interior of the sleeve. As shown, a portion of the sleeve wall is cut away to provide the solder cup configuration 4-2 and to enlarge the opening 43 to the interior of the member. The other end 44 is cut straight across or perpendicular to the longitudinal axis of the piece. The sleeve has a diameter slightly larger than the diameter of the shank with which it is to be assembled. The outer diameter of the sleeve is slightly greater than the diameter of the bore in an insulating body through which the shank extends.

To secure each contact to the insulating body and to also provide means permitting positioning a wire or conductor in electrically conductive relationship to the contact, the member E is slipped over the relatively short, protruding portion of the shank. As shown in FIG. 4, the sleeve member is telescoped for a part of its length over the end of the shank, with the inner end 44 of the sleeve located closely adjacent the insulating body A. The sleeve is crimped to the underlying shank at 46. The increased thickness provided by the Wall of the sleeve, together with the cooperation of the enlarged portion 32 with the internal shoulder 16 limiting movement of the contact in the opposite direction, serve to prevent the contact from being separated from the insulating body. The part of the sleeves length which extends beyond the end of the shank provides the recess 43, here enlarged by the cut-away portion 42, for the positioning of a wire or a conductor W therein. The conductor may be secured to the sleeve and hence, to the contact, by soldering or crimpmg.

It is preferred that the inner end of the sleeve 44 be spaced 2. short distance from the insulating body when the enlarged portion 32 of the contact is flush up against the internal shoulder 16 before securing the sleeve to the contact. 'In this manner, a slight amount of play lengthwise of the contact is obtained, thereby providing the desired play facilitating engagement of a pin contact with a mating socket contact.

As shown in FIG. 5, the socket contacts D similarly are secured to the insulating body B, and are each provided with a recess or solder cup to receive a Wire W by the simple expedient of crimping a member to the protrud ing portion of each contact shank.

In the embodiment of the invention illustrated in FIG. 6, the sleeve-like member E is in the form of a helically coiled spring, uniform in its innner and outer diameters and having closely adjacent turns. As shown in FIGS. 7 and 8, the short length springs serve to secure the contacts, pins and sockets, to their respective insulating bodies, each spring also affording a recess 45 for the positioning of a conductor therein. In this form of the invention, the short-length of coiled spring is secured in position by welding same to the shank after it is telescoped onto the shanks protruding portion. The inner diameter of the coiled spring initially may be less than the diameter of the shank; its elasticity permitting such form of sleeve to be fitted over the larger diameter shank. The outer diameter of the coiled spring, when on the shank, is larger than the diameter of the adjoining bore. Resistance welding electrodes, designated 47, 47, spot Weld the parts together at 48, 48'. Preferably, the wire which is posia tioned within the open end of the coiled spring is soldered thereto.

While the coiled spring, sleeve-like members E may we used to secure in position contacts C and D as shown in FIGS. 4 and 5, the contacts C and D, and correspondingly the insulating bodies A and B, may possess the configuration shown in FIGS. 7 and 8. Here the insulating body A is formed with laterally spaced cavities 50 which are of relatively shallow depth and formed so that each pin-mating socket portion 52 extends beyond the face of the insulating body. The insulating body B is provided with comparatively deep cavities 54 to surround socket-mating pin portions 56. Both the sockets and pins are provided with enlarged portions or flanges 58 and 60 for engagement with internal shoulders 62 and 64, respectively. The contacts each have rearwardly extending shanks s6 and 63 extending through the bores 70 and 72, respectively, for a short distance beyond their respective insulating bodies.

in the embodiment of the invention illustrated in FIG. 9, the sleeve-like member, designated E, is in the form of a sleeve or tube, the wall of which, however, is not continuous as in the showing of FIG. 3. This form of sleevelike member is fabricated from flat strip, preferably of a copper alloy, which is bent up to provide a narrow longitudinally extending opening or seam 74. One end of the piece may be cut away at 75 to enlarge the opening or recess 76 into the interior of the member. This form of member is secured to the contact by spot welding, and the wire is preferably connected thereto and the contact by soldering.

It will be apparent that the described procedure for assembling and securing the contacts to their insulating bodies obviates the necessity for cutting into the shank of the contact, reducing its cross-section and thereby Weakening its mechanical strength. From the standpoint of voltage breakdown, the wall thickness of the sleeve-like members is sufi'iciently small so that the distance between adjacent contacts may be kept to a minimum. Also, since the contacts shanks are of uniform diameter, and unbroken in cross-section, they may be made of smaller diameter than with the prior art technique, and still provide adequate mechanical strength, while increasing the paths of surface leakage between adjacent contacts for greater resistance to voltage breakdown.

The configuration of the sleeve-like members E, E and E", as illustrated in FIGS. 3, 6 and 9 is such that they lend themselves to automatic feeding and assembly with the contacts positioned in the insulating body. The members E and E", because of their solder cup configuration at one end, permit them to be readily oriented for feeding from a hopper. The coiled spring form of sleeve E, shown in E6. 6, is symmetrical or the same at both ends and, or" course, does not even require endwise orientation for hopper-feeding to the point of assembly with the contacts.

As previously indicated, it is preferred to form the insulating bodies of the connector halves with the external flanges 25 and 25'. Such structure enables retaining the connector halves in their coupled condition. As shown in FIG. 10, the flanges 25 and 25 are located on their respective insulating bodies so that they are spaced from one another a predetermined, fixed distance when the connector halves are coupled to one another, with the pin and socket contacts in mating engagement. To realize the "benefits of the flanged structure, mounting and retaining means in the form of a spring clip F, as illustrated in FIG. 11, may be utilized for separably mounting the electrical connector to a wall or support 80 (FIG.

The spring clip F comprises a base portion 82 having means in the form of a pair of longitudinally spaced apertures S4, 84' to permit securing the clip to the wall 80, as by rivets or the like passed through the apertures and through suitable openings in the Wall. If desired,.the base portion 32 may be provided with a downturned tab 86 at one or both ends thereof to be received in mating recesses (not shown) formed in the supporting wall, thereby additionally preventing relative movement between the clip and its support. The clip F is provided with opposite pairs of longitudinally spaced arms 88, 8S and 99, 90' formed integrally with the base 82. These arms are formed integrally with the base portion of the clip and are bent up to extend substantially perpendicularly to the base. Also, the upstanding arms are each shaped to provide concave surfaces 92 for mating engagement with the convex sides of the cylindrical insulating bodies A and B. The top end of each of the arms is reversely bent at 94 to facilitate insertion and removal of the coupled connector. g v

Significantly, the inner edges 96, 96 and 9 7, 97 of each pair of arms 88 and 88, and 9h, 90, respectively, are longitudinally spaced from one another a distance slightly greater than the external edges, designated 98 and $8, of the connector halves when they are in coupled condition, as shown in FIG. :10. As a result, when the coupled connector halves, having the wires in electrical continuity with the contacts, is pressed down in between the upstanding arms of the clip, the flanges 25 and 25 are received between the clips arms to prevent separation of the connector halves. On the other hand, the coupled connector may be readily lifted bodily from between the resilient arms of the spring clip when it is desired to disconnect the connector halves.

One or the other of the flanged connector halves is adapted for mounting on a panel by means of the device G shown in FIG. 12. The mounting device G may be secured to the front 1% of a panel 192, as shown in FIG. 13, or at the back 164 of the panel, as shown in FIG. 14. In each instance the panel is provided with a circular aperture MP5, or MS, which is slightly larger in diameter than the diameter of a connector half atthe area thereof adjacent its flanged portion 25 (or 25').

As shown in FIG. 12, the mountingdevice G comprises an inverted cup-like portion we having a central opening 107 in the inturned wall 1% thereof. The circumferential side wall 110 terminates in a pair of laterally extending ears 112 and 112 each of which is provided with means in the form of an aperture lid and 114', respectively, to enable securing the device to a panel, as by rivets or a nut and bolt arrangement. The internal diameter of the side wall Hi9 is slightly greater than the flanged area of the insulating body. The diameter of the opening 197 is slightly greater than the diameter of an insulating body at the area thereof adjacent the external flange. The internal height of the side wall 110 is slightly greater than the width of the flange 25 (or 25). The inturned wall 108 is provided with a cutout or notch 115 in communication with the opening 107. The mounting device G is preferably blanked and formed from metal. If desired, the device may be molded of plastic material having suitable mechanical strength.

For a front-of-the-pancl mounting as shown in FIG. 13, one of the connector halves, here shown as the connector half B, which is assembled with socket contacts, is positioned in the cup-like member so that the flange 25' is seated against the underside of the inturned wall 103. The portion of the insulating body B, designated 118, which is forward of the flange extends through the opening 107 with a slight amount of clearance. In order to prevent rotation of the connector half, the aperture 105 in the panel 1492 is provided with a notch in communication with the aperture 1&5. The main body portion, designated 122, of the connector half is then extended through the panel aperture M95 with the lug 27' extended through the panel notch 12% until the rear edge of the flange is seated against the front wall of the panel. A suitable connecting means is then passed through the apertures 114 and 114 and aligned openings made in the panel to secure the entire assembly in position.

For a behind-the-panel mounting, as shown in FIG. 14, the panel aperture N5 does not require notching. The mounting device G is slipped over the portion 122 rearwardly of the flange 25 with the lug 27 positioned in the notch 116. The assembly is then secured to the rear side 104 of the panel with the portion 118 of the insulating body extending through the aperture 105 and to the front 100 of the panel.

With the connector half secured in position, as shown in either FIG. 13 or FIG. 14 and prevented against rotation about its longitudinal axis, the mating connector half may be coupled therewith. It will be apparent that either the pin connector half or the socket connector half may be mounted on the panel in the front of or back of relationship as shown.

While several preferred embodiments of the invention have been specifically described and illustrated, it will be apparent that various modifications and changes may be made without departing from the spirit and scope of the invention as sought to be defined in the following claims.

I claim:

1. In a miniature electrical connector of the multiple pin and socket type, an insulating body having a cavity and a bore of smaller diameter communicating therewith providing an internal shoulder, a contact having an enlarged portion for engagement with said shoulder and a rearwardly extending shank of reduced diameter, said shank having a diameter less than the diameter of said bore, said shank being positioned in said bore and having a portion thereof extending exteriorly a short distance beyond the insulating body, and a diametrically expansible sleeve like member having an outer diameter slightly greater than the diameter of said bore telescoped for part of its length over the exteriorly extending portion of the shank and secured thereto, the inner end of said member being located closely adjacent to but slightly spaced from said body, said sleeve-like member cooperating with said enlarged portion and said shoulder to retain the contact to the insulating body, the part of the sleeves length extending beyond the end of the shank providing a recess for the positioning of a conductor herein.

2. In a miniature electrical connector of the multiple pin and socket type as set forth in claim 1, wherein the sleeve-like member comprises a short length of coiled spring.

3. In a miniature electrical connector of the multiple pin and socket type as set forth in claim 1, wherein the sleeve-like member comprises a short length of coiled spring; and wherein the coiled spring is secured to the shank by welding.

' 4. In a miniature electrical connector of the multiple pin and socket type as set forth in claim 1, wherein the sleeve-like member comprises a longitudinally split sleeve.

5. In a miniature electrical connector of the multiple pin and socket type as set forth in claim 1, wherein the sleeve-like member comprises a longtiudinally split sleeve; wherein the Wall of the member at one end thereof is cut away for partof its circumference to enlarge the opening to the interior of the member; and wherein the member is welded to the shank.

References Cited in the file of this patent UNITED STATES PATENTS 2,088,322 Hen-hing July 27, 1937 2,200,332 Henning May 14, 1940 2,500,892 Bennett Mar. 14, 1950 2,563,762 Uline et a1. Aug. 7, 1951 2,690,541 Elliott Sept. 28, 1954 2,720,633 Westberg Oct. 11, 1955 2,732,534 Giel Jan. 24, 1956 2,736,870 De Jur et al Feb. 28, 1956' 2,738,486 Wadsworth Mar. 13, 1956 2,813,257 Cornell Nov. 12, 1957 2,820,213 Sheehan Jan. 14, 1958 2,856,674 2 Hill Oct. 21, 1958 2,869,091 Robards Jan. 13, 1959 2,896,186 Hardmark July 21, 1959 2,917,722 Cobbett et a1 Dec. 15, 1959 2,938,190 Krehbiel May 24, 1960 2,968,020 Barnhart Jan. 10, 1961 3,003,135 Purinton Oct. 3, 1961 3,059,209 Bird Oct. 16, 1962

Claims (1)

1. IN A MINIATURE ELECTRICAL CONNECTOR OF THE MULTIPLE PIN AND SOCKET TYPE, AN INSULATING BODY HAVING A CAVITY AND A BORE OF SMALLER DIAMETER COMMUNICATING THEREWITH PROVIDING AN INTERNAL SHOULDER, A CONTACT HAVING AN ENLARGED PORTION FOR ENGAGEMENT WITH SAID SHOULDER AND A REARWARDLY EXTENDING SHANK OF REDUCED DIAMETER, SAID SHANK HAVING A DIAMETER LESS THAN THE DIAMETER OF SAID BORE, SAID SHANK BEING POSITIONED IN SAID BORE AND HAVING A PORTION THEREOF EXTENDING EXTERIORLY A SHORT DISTANCE BEYOND THE INSULATING BODY, AND A DIAMETRICALLY EXPANSIBLE SLEEVE-LIKE MEMBER HAVING AN OUTER DIAMETER SLIGHTLY GREATER THAN THE DIAMETER OF SAID BORE TELESCOPED FOR PART OF ITS LENGTH OVER THE EXTERIORLY EXTENDING PORTION OF THE SHANK AND SECURED THERETO, THE INNER END OF SAID MEMBER BEING LOCATED CLOSELY ADJACENT TO BUT SLIGHTLY SPACED FROM SAID BODY, SAID SLEEVE-LIKE MEMBER COOPERATING WITH SAID ENLARGED PORTION AND SAID SHOULDER TO RETAIN THE CONTACT TO THE INSULATING BODY, THE PART OF THE SLEEVE''S LENGTH EXTENDING BEYOND THE END OF THE SHANK PROVIDING A RECESS FOR THE POSITIONING OF A CONDUCTOR HEREIN.

Images