CA1066378A

CA1066378A - Electrical connector having threaded coupling nut

Info

Publication number: CA1066378A
Application number: CA273,788A
Authority: CA
Inventors: Robert W. Brush
Original assignee: Bendix Corp
Current assignee: Bendix Corp
Priority date: 1976-08-30
Filing date: 1977-03-11
Publication date: 1979-11-13
Also published as: GB1533226A; JPS5329591A; DE7720275U1; DE2729181A1; JPS5734981U; IL52314A0; FR2363209B1; FR2363209A1; IL52314A; IT1084756B

Abstract

ELECTRICAL CONNECTOR

ABSTRACT
An electrical connector that is capable of being quickly coupled and decoupled. The coupling and decoupling is accomplished by a coupling nut having a triple start thread (310) that allows .3 inches of axial movement for 360° of rotation of the coupling nut when the coupling nut is mated to the threads of a connector shell. The triple threads (311, 312, 313) also minimize radial and axial deflection between a coupling nut (300) and a connector shell (200) and between the male and female electrical contacts (270, 370), when the two halves of the connector assembly are connected together. This minimizes wear of the engaging surfaces and increases the life of the conductor.

Description

BACKGROUND OF THE INVENTION
This învention relates to electrical connectors of the type having coupling nuts for coupling and decoupling an electrical connector assembly.
This invention is more particularly related to an improved thread type electrical connector assembly that provides greater axial movement between the mateable parts when the coupling nut is rotated 360 so that the coupling and mating of the assembly is accomplished as quickly as possible; it also provides minimal radial and axial deflection between the two halves of a connector assembly when they are connected together.
There is a continual need to improve electrical connectors to meet the rigid performance standards existing in the Aerospace field. Electrical connectors should be easily and quickly coupled and decoupled with the use of acceptable force. Further, the wear of a connector assembly should be as minimal as possible so that the connectors have a long life. This minimizes the expense of replacement and the loss of the use of electrical equipment during replacement of failed or worn connector assemblies. Further, to couple together connector assemblies quickly and properly, it is important that for each revolution of a coupling nut a maximum axial movement is obtained.
Further, the electrical connector when coupled should remain securely coupled when subject to extensive vibration. Considering all these problems and requirements it is important to balance each of them to obtain the maximum advantages and the minimum disadvantages.
Another problem associated with mating electrical connector assemblies is that radial and axial deflection of the male and female electri-cal contacts should be minimized when the coupling nut is mated to a connector shell so as to minimize the wear on the electrical pin and socket contacts within the shells when they are initially mated.
One example of an electrical connector that provides for quick coupling and decoupling of a connector assembly is shown in U.S. Patent

2,98~,811, issued May 16, 1961 to W. F. Hennessey, Jr., et al and entitled i;
"Electrical Connector". This patent illustrates a bayonet lock type electrical .

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conrlector which has a coupling nut which, instead of threads, has one or more grooves in it for mating with pins on a connector shell thereby permitting quick coupling and decoupling of tlle electrical connector assembly. A dis-advantage associated with this type of electrical connector is that the bayonet pins, which reduce radial deflection from that which occur in a threaded coupling nut, take the brunt of the forces generated during coupling and vibration.
Therefore, the pins are subjected to wear. For instance, the pins would break, partially, or completely shear off allowing the coupling nut to lose its retaining function and allow the two halves of the electrical connector to separate. Therefore, there has always been a need for an electrical connector which: (1) could be quickly coupled and decoupled; (2) when subject to vibration, would remain securely connected together; (3) required an acceptable amount of force.to connect together; (4) had minimum wear of the engageable connector parts; ~5) traveled a maximum distance axially for each revolution of the coupling nut; and (6) had minimal radial deflection of the electrical contacts when the coupling nut was engaged and tightened to mate and draw the electrical contacts to~ether, thereby minimizing wear of the metal components of the connector ~assembly and the threads themselves.
SUMMARY OF THE I~VENTION : -This invention provides a quickly connectable and dlsconnectable electrical connector assembly (with an acceptable amount of coupling force) that travels a maximum axial distance for each revolution of a coupling nut while minimlzing radial and axial deflection of the electrical contacts within the assembly thereby minimizing wear of ~ the electrical contacts and the coupling threads.
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having first and second shells connectable in alignment with the first shell having an enlarged portion located intermediate of its length, the enlarged portion having a forwardly-facing shoulder and a rearwardly-facing shoulder and the second shell having a surface adapted to seat on the forwardly-facing shoulder of the first shell when the first and second shells are-connected.
lnterfitting keying means are provided on the shells to allow their axial approach and retreat while preventing ; 10 rotation relative to each other. An insulating insert ; is mounted within each shell. Cooperating pin and socket ; type electrical contacts are provided, the pin contacts being mounted in one of the inserts and the socket contacts being mounted in the other insert, the pin and socket contacts connectable in mated relationship. Means are `- provided for connecting the first and second shells together in seated relationship, the means comprising: a sleeve rotatably mounted on the first shell the sleeve including a forwardly-facing surface located and adapted ~0 to seat on the rearwardly-facing shoulder of the first shell; means for retaining the sleeve against axial removal .~. . : .
~ in either direction from the first shell; and -interfitting : , :
thread means in the sleeve and on the second shell, each of the thread means comprising three separate and distinct threads whereby when the first and second shells are !~ -' placed in axial alignment with the keying means interfitting and the sleeve is rotated in one direction, the three thread.s in the sleeve interfit with the three threads on the second shell connecting the pin and socket contacts in a secure mated relationship with the surface of the second shell seated on the forwardly-facing shoulder of the first shell and the surface of the sleeve seated on -the rearwardly-facing shoulder of the first shell.

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The Eoregoing arrangement provides an electrical connector that is quickly connectable and disconnectable with an acceptable amount of rotational force while minimi~ing the radia] and axial deflection associated with an electrical connector when the coupling nut initially engaged is coupled to one of the connector shells.
Accordingly, it is an object of this invention to provide an improved electrical connector that has a long and reliable life when subjected to the rugged ~ 10 environment encountered in Aerospace applications.

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It is another object of this invention to provide an electrical connector that cannot be easily cross-threaded, i.e., misthreaded.
It is still a further object o~ this invention to provide a coupling nut that has the same basic turning requirements to couple and uncouple a connector assembly as does a bayonet type electrical connector assembly.
The above and other objects and features of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings and claims which form a part of this specifica-tion. Further, the use of reference numerals is for the purpose of clarifica-10 tion only and is not intended to limit the invention to the specific structure referenced and shown.

BRIEF DESCRIPTION OF THE DRAWINGS
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Figure 1 is a cut away view of the three main portions of an electrical connector assembly.
Figure 2 is a cut away view of an electrical connector assembly when connected together.
Figure 3 is an end view of the coupling nut taken along lines III-III of the coupling nut shown in Figure 1.
Figure 4 is a cut away view of connected electrical connector 20 assembly shown in Figure 2 taken along lines IV-IV. ~:
Figure 5 is an end view of one-half of the electrical connector assembly shown in Figure 1 and taken along lines V-V.

DESCRIPTION OF THE PREFERRED EMBODIMENT
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I Referring now to the drawings, Figure 1 illustrates a cross-sectional ; exploded view of an electrical connector assembly which incorporates the principles of the invention. An electrical connector assembly comprises a first shell 100, a second shell 200, and a coupling nut 300 mounted on one o~ the shells 100 for connecting the shells together. The typical components of one-.
half of an electrical connector assembly include a ~irst shell 100 containing ;' .

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one or more Female type (socket) electrical contacts 170 retained within the shell 100 by inserts 110, 120, 130. The outside of the first shell 100 generally includes a rear portion that is threaded for receivin~ a moisture sealing and/or strain relief nut (not ~hown) and a forward portion that includes one or more axially extending projections or keys for orienting the first shell with a second shell 200.
The second shell 200 contains one or more male type (pin) electrical contacts 270 that mate with the socket contacts 170 of the first shell 100 retained within the second shell 200 by one or more inserts 230. The male pin type contacts may also be retained in the same manner as the female socket type contact 170 of the first shell 100 are retained. Within the forward portion of the second shell 200 there are one or more ax-ially extending recesses -~
or keyways 201 that are engageable with the key 101 on the first shell 100.
The keys 101 on the first shell 100 and the keyways 201 in the second shell 200 operate as keying means to locate the first and second shells in their proper positions so that when there are a plurality of male and female contacts they engage in a predetermined manner. On the forward portion of the outside o~
the second shell 200 there are a plurality of threads 210 ~or receivlng the threads 310 of the coupling nut 300.
The coupling nut 300 is rotatably mounted on the first shell 100 by a snap ring 400 which is snapped into a groove 102 in the first shell 100 thereby captivating the rear end portion 305 of the coupling nut 300 between the rearwardly facing shoulder 103 of the first shell 100 and the snap ring 400. The coupling nut 300 includes, on the inside forward portion, threads 310 that are mateable with the threads 210 on the outside forward surface of the second shell 200.
Figure 2 illustrates an electrical connector assembly wherein the two halves of the electrical connector assembly are coupled together. The coupling nut 300 has been threaded onto the second shell 200 drawing together the pin contacts 270 into the socket contacts 170. This figure also illustrates how the male or female electrical contacts 170 may be removably retained within the connector shell. In this embodiment a plastic insert 110 has forwardly extending fingers 111 that engage the rearwardly facing shoulder 171 of the socket contact 170. ~y insertion of a proper tool the forwardly extending fingers 111 may be radially deflected, thereby allowing the socket contact 170 to be removed from the inside of the first shell 100. Also included in this connector assembly is a rubber grommet 500 that forms an annular seal between the first shell 100 and the second shell 200 when the coupling nut (300) draws the two shells together and compresses the gasket or grommet 500.
Figure 3 illustrates an end view of the coupling nut 300 taken along lines III-III of Figure 1. This view illustrates the threads 310 within the coupling nut 300. It is essential to the invention that the threads 310 be comprised of at least three separate threads 311, 312, 313. Preferably, each of the threads 311, 312, 313 begin at approximately 120 from the other.
This symmetrical spacing minimizes the problem of cross-threading that would be present when less than three threads are used and minimizes radial deflection to a degree that results in negligible wear on the threads and the electrical contacts.
Figure 4 illustrates a cross-sectional view of the connector assembly shown in Figure 2 taken along lines IV-IV. The coupling nut 300 which is rotatably mounted to the first shell 100 may be rotated in either direction.
Preferably, when the coupling nut is rotated in direction A and -the threads are mated with the threads 210 on the second shell 200, the two shells 100, 200 of the connector assembly are drawn together engaging the electrical contacts 270, 170 and compressing the gasket 500.
Figure 5 is a cross-sectional view of the second shell 200 taken along lines V-V of Figure 1. The threads 210 on the outside forward portion of the second shell 200 are comprised of three separate threads 211, 212, 213 which are also symmetrically arranged one from the other at approximately 120 apart.
Referring now to the drawings in general, the connector assembly would be coupled together in the following manner: First the keying means 101, 201 of the first and second shells 100, 200 are aligned and then the threads 310 of ' ,, , , , , ,..... . ., :
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the coupling nut 300 are engaged with the threads (210) of the second shell 200. By rotating the coupling nut 300 in direction A, the male contacts 270, which have been aligned with the female contacts 170 by the keying means 101, 201 are drawn together into mated relationship. The coupling nut is rotated in direction A until the rubber gasket 500 is compressed to form a moisture proof seal between the first and second shells 100, 200.
While a preferred embodiment of the invention has been disclosed it will be apparent to those skilled in the art that changes may be made to the invention as set forth in the appended claims, and, in some cases~ certain features of the invention may be used to advantage without corresponding use of other features. Accordingly, it is intended that the illustrative and descriptive materials herein be used to illustrate the principles of the invention and not o limit the scope thereof.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A separable electrical connector comprising:
first and second shells connectable in alignment with said first shell having an enlarged portion located intermediate of its length, said enlarged portion having a forwardly-facing shoulder and a rearwardly-facing shoulder and said second shell having a surface adapted to seat on the forwardly-facing shoulder of said first shell when said first and second shells are connected;
interfitting keying means on the shells to allow their axial approach and retreat while preventing rotation relative to each other;
an insulating insert mounted within each shell;
cooperating pin and socket type electrical contacts, said pin contacts mounted in one of said inserts and said socket contacts mounted in said other insert, said pin and socket contacts connectable in mated relationship; and means for connecting the first and second shells together in seated relationship, said means comprising:
a sleeve rotatably mounted on the first shell said sleeve including a forwardly-facing surface located and adapted to seat on the rearwardly-facing shoulder of said first shell;
means for retaining the sleeve against axial removal in either direction from said first shell; and interfitting thread means in said sleeve and on said second shell, each of said thread means comprising three separate and distinct threads whereby when said first and second shells are placed in axial alignment with said keying means interfitting and said sleeve is rotated in one direction, the three threads in said sleeve interfit with

claim 1 cont'd......
the three threads on said second shell connecting the pin and socket contacts in a secure mated relationship and the surface of said second shell seated on the forwardly-facing shoulder of said first shell and said surface of said sleeve seated on the rearwardly-facing shoulder of said first shell.