Connector Assembly Having an Anti-Decoupling Mechanism

This invention relates to a connector assembly of the type having a coupling ring for coupling and decoupling the two housings of the connector assembly. The invention is more particularly related to an improved anti-decoupling mechanism that retains the coupled housings together against forces, such as vibration, which tend to uncouple the housings.

A connector assembly is used to connect together separate lines that convey a signal; such as wires in electrical circuitry and optical fibers in light transmitting circuitry. The assembly includes two housings that may be coupled together by a coupling ring rotatably mounted on one of the housings. The other housing and the coupling ring each have threads which when mated together, and the coupling ring rotated, draws the housings together and mates respective electrical contacts mounted within the housings. To prevent decoupling of connector housings, some connector assemblies include anti-decoupling mechanisms that are comprised of one or more springs having a projection thereon mounted on the inside of the coupling ring and a plurality of teeth annularly arranged and projecting from one of the housings that engage the projections. One example of an electrical connector assembly having this type of anti-decoupling mechanism may be found in U.S. Pat. No. 4,109,990 issued Aug. 29, 1978 and entitled "Electrical Connector Assembly Having Anti-Decoupling Mechanism". In this arrangement the projections on the springs are continuously pressed against the teeth during the coupling and decoupling of the connector housings. This results in excessive wear of the projections and the teeth after the housings have been coupled and decoupled 500 times or more to comply with durability requirements. As the ratchet teeth and projection on the spring wear, the anti-decoupling mechanism becomes less effective. This increases the likelihood that the coupling ring will rotate and cause partial or complete decoupling of the housings. In an electrical connector this causes partial of complete unmating of the electrical contacts within the respective connector housings, which results in the loss of diminution of the electrical signal conveyed by the contacts.

This invention reduces the wear between the engaging members of an anti-decoupling mechanism for a connector assembly of the type utilizing a spring and ratchet teeth arrangement between a coupling ring and a connector housing. The invention is characterized by an axially extending portion at the free end of each of the springs that is adapted to engage a respective shoulder on the other housing and apply additional pressure between the spring and teeth during the last few degrees of rotation during coupling of the housings.

One advantage of this invention is that it improves the durability of the anti-decoupling mechanism of a connector assembly.

Another advantage of this invention is that it increases the effectiveness of the anti-decoupling mechanism over previous mechanisms.

Another advantage of the invention is that it provides for an increase of pressure between the engaging members of the anti-decoupling mechanism during the last portion of the final coupling rotation of the coupling ring.

FIGS. 1 and 2 illustrate a partial diagrammatic view of the anti-decoupling mechanism of an electrical connector assembly.

FIG. 3 is an end view of the receptacle for an electrical connector assembly shown in FIG. 4.

FIG. 4 illustrates an exploded view of a connector assembly incorporating the features of this invention.

Referring now to the drawings, FIG. 1 is a partial view of a connector assembly which illustrates the anti-decoupling mechanism incorporating the principles of this invention. This Figure illustrates the coupling ring 30, which is rotatably mounted on one of the housings 20, just before it is completely coupled to the other housing 10. A spring 40 is mounted at one end to the inside of a coupling ring 30 which couples together two housings 10, 20. One of the housings 10 includes a thread 11 on the forward portion thereof that starts with an axially extending shoulder 12. The other housing 20 includes a plurality of radially extending and annularly arranged teeth 21 that engage an inwardly extending radial projection 41 on the spring 40.

FIG. 2 illustrates a partial view of a connector assembly with the coupling ring 30 completely coupled to the housing 10. During the last portion of the rotation of coupling the coupling ring 30 to the housing 10, the axially extending end portion 42 of the spring 40 engages the blunt start shoulder 12 of the thread 11 and upon further rotation of the coupling ring 30 in the same direction causes the projection 41 to be pressed further between the teeth 21 on the other housing 20 hence, increasing the pressure between the projection 41 and the teeth 21.

FIG. 3 is an end view of a receptacle for the electrical connector assembly shown in FIG. 4. This view illustrates that there are preferably three threads 11 on the receptacle housing 10 and that each of the threads has a blunt start, i.e., an axially tapered shoulder 12 rather than a tapered portion.

FIG. 4 illustrates an exploded view of a connector assembly incorporating the features of this invention. The connector assembly is generally comprised of a first housing 10, a second housing 20, and a coupling ring 30. Not shown are electrical contacts or optical fiber terminals that may be mounted within the housings 10, 20. The coupling ring 30 is rotatably mounted to the housing 20 by captivating its radial flange portion 32 against the annular shoulder 22 of the housing 20 by a snap ring 60. Mounted inside the coupling ring 30 there are preferably three springs 40. Each of the springs 40 has a radial projection 41 and an axially extending portion 42 which is adapted to engage a blunt start or axial shoulder 12 of the thread 11 on the housing 10. Each of the springs 40 is mounted inside the coupling ring 30 by a pin 50 that extends through a hole 33 in the flange 32 of the coupling ring 30 and through the coiled end portion 44 of the spring 40. Inside the coupling ring 30 there are three threads 31 which match the number of threads 11 on the housing 10.

To couple the connector assembly together the coupling ring threads 31 are engaged with the threads 11 on the housing 10 and the coupling ring 30 is rotated. This draws the second housing 20 into the first housing 10 to mate any electrical contacts or fiber optic terminals mounted within the housings 10, 20. During the last five degrees of rotation of the coupling ring 30 onto the housing 10 the axially extending portion 42 of the free end of the spring 40 engages the shoulder 12 on the threads 11 and moves the projection 41 on the spring 40 inwardly. This causes a greater pressure between the projection 41 on the spring 40 and the teeth 21 on the housing 20. This increased pressure between the projection 41 and the teeth 21 helps to prevent decoupling of the housings 10, 20 when the coupled connector assembly is subjected to vibration.

While a preferred embodiment of the invention has been disclosed, it will be apparent to those skilled in the art that minor changes may be made to the invention as set forth in the appended claims and, in some instances 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 to limit the scope thereof.