US 3569918 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
United States Patent l 13,569,918
72] Inventor Bruce -Ar 181,648 8/1876 Disston 145/108X pasadellatcalif- 2,154,012 4/1939 Rhodes 85/39 1 PP 872,568 6 FOREIGN PATENTS ggfg g': f 574,406 3/1924 France 339/214  Assignee lntemafionalTelephoneandTelegraph 649,739 1/1951 GreatBntam 339/215 Corporation Primary ExaminerMarvin A. Champion New York, N.Y. Assistant Examiner-Robert A. Hafer  MULTIPIECE ELECTRICAL CONTACT Attorneys-C. Cornell Remsen, Jr., Walter J. Baum, Paul W. Hemminger, Percy P. Lantzy and Thomas E. Kristofferson ABSTRACT: A multipiece electrical contact having a mating portion, the front end of which is adapted to be interconnected with the mating portion of another electrical contact' MULTIPIECE ELECTRICAL CONTACT The invention relates in general to multipiece electrical contacts, and more particularly, to a contact retention system for mounting in a monoblock insulator.
BACKGROUND OF THE INVENTION Conventional pin and socket contacts have been mounted in an insulator by utilizing a retaining shoulder around the body of the contact which is captivated between a front and rear insulator. Such a technique requires the separate molding to two individual insulators which must later be combined. Further, because of this two-piece insulator construction, moisture or contamination between the two insulators can result in a voltage breakdown or otherwise reduce the electrical capabilities of the connector.
Alternatively, the pin or socket contact may be assembled with a separate retaining device attached to the body of the contact. The contact is then inserted into a single piece insulator body by pushing the contact into the insulator. When the contact is in position, the retaining member permanently locks the contact in the insulator. However, the use of separate retaining devices on the contact requires stringent process control to ensure minimum contact axial displacement under load and minimum contact splay.
More frequently, however, the retaining members have been molded in or assembled in the contact insulator cavity. A typical type contact retention system of the type which is formed in the insulator is described in Us. Pat. No. 3,158,424. In such an arrangement axial displacement and contact splay can be more easily controlled than when the contact retaining device is mounted directly on the contact itself. However, stringent process control is still required.
A still further technique would be to mold the pin or socket contact directlyinto the insulator. However, as is readily apparent, not only is molded-in construction usually more costly to produce, but in multicontact arrangements, if one contact is bad, there is no way to replace the contact and the entire assembly must be discarded.
In order to overcome the attendant disadvantages of prior art contacts for mounting in an insulator assembly, the present invention utilizes a monoblock insulator which eliminates the shortcomings of two-piece insulator construction. By adjusting the dimensions and tolerances of the novel contact, axial displacement under load can be controlled and completely eliminated if desired. Further, replacement of bad contacts is possible as the contact is removable, thus eliminating the necessity of discarding the entire connector assembly. Moreover, because of the simplicity of the components of the contact and the interchangeability thereof, the cost of the contacts are greatly reduced and the ability to automate both the construction of the contacts and assembly thereof into an insulator is enhanced.
The advantages of this invention, both as to its construction and mode of operation will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like referenced numerals designate like parts throughout the FIGS.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an exploded view of a preferred embodiment of a pin contact prior to mounting in an insulator in accordance with the invention;
FIG. 2 shows the pin contact of FIG. I mounted in an insulator; and
FIG. 3 illustrates a socket contact utilizing the assembly technique of the type shown in FIGS. 1 and 2 and which may be mated with the pin contact of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, there is shown an exploded view of the two-piece pin contact in accordance with the invention prior to mounting in an insulator member 12. The contact comprises a mating portion 14 and a termination portion 16. The front end of the contact comprises a pin member 18 for mating with a typical socket contact. The rear end of the pin member 18 is connected to an enlarged collar 22 formed of a cylindrical section 24 and a tapered front section 26 whose rear diameter is equal to the cylindrical section 24 and whose front diameter tapers so that it is equal at its front end to the pin member 18, and is made integral therewith. The rear end of the collar 22 has'a rearward facing shoulder 28. Extending rearwardly axially from the portion 24 of the collar 22 is a cylindrical shank member 32 having a slightly tapered rear end 34. The main portion of the shank member 32 contains, around its outer surface, axially extending knurls 36.
The termination portion 16 of the contact is formed of a rear cylindrical member 42 which terminates in an enlarged collar 44, and forward cylindrical section 46 extending forwardly from the front end of the collar 44. The forward facing surface of the collar forms a shoulder 48. A front opening bore 52 in the member 16 extends through the entire length of the cylindrical section 46, the collar 44, and into the front end of the rear cylindrical member 42. The bore 52 is tapered as at 54 at the front end of the section 46. Further, a rearwardly opening bore 56 in the member 42 forms a solder pot. A rear portion of the member 42 is removed as at 58 so as to form the solder pot as is conventional.
The mating portion and termination portion of the contact are designed to be mounted in an insulator member such as member 12. The insulator member 12 contains a central bore portion 62 and an enlarged forward bore portion 64 having a forward facing shoulder 66, and an enlarged rear bore 68 having a rearward facing shoulder 72 formedat the junction of the bores 62 and 68.
Referring now to FIG. 2, as can be readily seen, contact is assembled in the insulator 14 with the shank member 32 extending first into the bore 64 and the front cylindrical section 46 extending into the bore 68. The shank member 32 enters the bore 52 and forms a tight fit therein. The knurls 36 facilitate insertion of the shank. The forward facing shoulder 48 abuts the rearward facing shoulder 72 and the rearward facing shoulder 28 abuts the forward facing shoulder 66 of the insulator. Thus, a tight fit is formed between the two portions 14 and 16 of the contact with axial movement in the insulator not possible.
Referring not to FIG. 3, there is shown an alternative configuration wherein a socket contact 82 is utilized in place of the mating portion 14. As can be readily seen, an identical termination portion 16 is utilized, although, of course, other configurations are possible. The socket contact 82 contains a hooded front end 84 which is connected to a collar 86 by means of reduced diameter sections 88 and 90. The rear end of the collar contains a knurled shank 92 for insertion into the bore 52 of the termination portion 16 in a manner depicted in FIG. 2.
Further, it should be understood that by making the mating portion 18 or 82 and termination portion 16 of two piece construction, that different materials could be used for each portion. For example, mating portion 14 could be made of a high strength conductive alloy such as leaded nickel copper, the socket contact 82 could be made of beryllium copper, and terminal portion 16, which forms a solder pot could be made of an inexpensive brass, each portion advantageously using the metal to the best ability.
Moreover, it should be understood that the contact could be utilized in environments other than as depicted and need not be mounted between the two flanges of the insulator member 12.
Also, while the bore 52 is depicted as part of the termination portion 16 and the shank member 32 as apart of the mating portion 14 it should be understood, of course, that the contact could as easily be formed with the bore as part of the mating portion and the shank member as part of the termination portion.
I claim: 1. A multipiece electrical contact for assembly in a onepiece insulator member comprising:
said insulator member having a front end and a rear end and having a bore with a forward facing shoulder formed at one end of said bore and rearward facing shoulder formed at the other end of said bore; and multipiece contact being formed of a mating portion and a terminating portion, said mating portion having a rearward facing shoulder and said terminating portion having a forward facing shoulder, said mating portion and said terminating portion being inserted from the front end and the rear end, respectively, of said insulator member and wherein said contact portions are secured to each other and wherein said rearward facing shoulder of said mating portion abuts said forward facing shoulder of said insulator member and said forward shoulder of said terminating portion abuts said rearward facing shoulder of said insulator member, one of said portions having a cylindrical member extending from its shoulder into said bore and the other of said portions having a shank member extending from its shoulder into said bore and mating with said cylindrical member and forming a tight fit therewith.
2. A multipiece electrical contact in accordance with claim 1 wherein the front end of said cylindrical member abuts the shoulder of said shank member.