GB2046533A - Electrical connectors - Google Patents

Abstract

In electrical connectors of the wire-wrap type, each connector contact 16 is fitted with a wire-wrap post 22 of square cross-section which is secured against twisting during wire-wrapping operations and is aligned in the connector shell 10 by a rigid support disc 24 having square apertures 26, by a mass of hardened potting compound 28 and by a resilient support 12 having an aperture 13 in which the contact 16 is an interference fit. <IMAGE>

Description

SPECIFICATION Improvements in electrical connectors The present invention relates to two-part electrical connectors.

It has been proposed to utilise wire-wrap techniques to make electrical connections between the wires and the terminals of electrical connectors, for example, plugs and sockets. To achieve this it has been proposed to provide a wire-wrap post of, for example, square or triangular cross-section, connected to each contact and to wrap the conductor wire tightly around the terminal post. The corners of the wire-wrap post "bite" into the wire and thus a secure, conducting contact between the wire and the contact of the connector is produced.

In order to make a connection of this type efficiently it is necessary to ensure that each wire-wrap post is very securely fixed in the connector so that the turning forces exerted on the post during the wire-wrapping processes are withstood. It has been proposed to provide ribbed portions on the body of each contact and to pot the contacts in a potting compound and thus prevent rotation or twisting of the contacts during the wire-wrapping process.

It is one object of the present invention to provide an improved electrical connector in which the contacts are provicied with wire-wrap terminal posts and which is such that manufacture is facilitated with precise location of the contacts and their terminal posts and improved resistance to damage during subsequent wire-wrapping operations is provided.

It is another object of the invention to provide a method of making a connector-part according to the invention.

According to the present invention there is provided one part of a two-part, multi-contact, electrical connector, wherein each contact has a wire-wrap terminal post, projecting rearwardly therefrom, the contacts each being an interference fit in respective apertures in a resilient dielectric support which is an interference fit in the shell of the connector and being further supported by a mass of potting compound in the shell rearwardly of the dielectric support, the terminal posts projecting through apertures in a fixed rigid dielectric disc mounted rearwardly of the potting compound with the walls of the apertures closely fitting the respective terminal posts, the disc serving to locate the terminal posts and sub stantiallyto prevent twist of the forward ends of the posts during subsequent wire-wrapping operations.

Further according to the invention there is provided a method of making one part of a two part, multi-contact, electrical connector, including the steps of providing a rigid shell, inserting a resilient dielectric contact-support into the shell, the support having a plurality of apertures therethrough and being an interference fit in the shell, inserting a contact into each aperture in the support, the contacts being longitudinally aligned with one another with the aid of a jig, each contact being an interference fit in its aperture in the support and having a wire-wrap terminal post projecting rearwardly therefrom beyond the rear of the shell, potting the contacts in the shell to the rear of the support in liquid potting compound, closing the rear of the shell with a rigid dielectric disc having in it apertures through which the wire-wrap posts pass and which closely fit the wire-wrap posts, and allowing the potting compound to set. Thus during manufacture of the connector-part the rigid dielectric disc serves as a jig to locate the terminal posts laterally with respect to the shell until the potting compound is set. Thereafter the disc prevents twist of the forward ends of the posts during wire-wrapping operations and hence provides an insurance against damage to the contact as a whole and to the bond with the potting compound. In addition the rigid disc provides a surface on which symbols for identifying the wire-wrap posts can be printed.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a portion, partly in cross-section, of one (male) part of a two-part electrical connector, and Figure 2 shows a portion, partly in cross-section, of another (female) part of a two-part electrical connector.

Referring to Figure 1, this shows a first (male) part of a two-part electrical connector having a shell 10 of standard dimensions nad a resilient dielectric support 12 which is an interference fit in the shell 10 and is located both by engagement of a circumferential ridge 25 on the inside of the shell 10 and a circumferential groove 21 on the support 12 and by abutment of a ramped circumferential shoulder 29 of the support 12 on a complementary ramped circumferential ridge 31 of the shell. A layer of adhesive (not shown) further secures the support 12 in the shell 10. Connector contacts, in the form of pins 16, pass through apertures 13 in the support 12, each contact being an interference fit in its aperture. Each pin 16 has a portion 20 of increased cross-section which forms a seal with the walls of its respective aperture 13.Wire-wrap posts 22 of square cross-section extend rearwardly (towards the right-hand end in Figure 1) from the pins 16 and may be crimped thereto or formed integrally therewith. A mass of hardened potting compound 28 fills the space within the shell 10 to the rear of the resilient dielectric support 12. The rear of the shell 10 is closed by a rigid dielectric support disc 24 having in it square apertures 26 through which the wire-wrap posts pass, the disc 24 fitting tightly within the shell 10 around its periphery, and being located circumferentially by engagement of a peripheral peg 32 in a corresponding notch 34 formed in the shell 10. Alternatively, this location may be provided by a notch in the disc and a peg on the shell. Identification symbols (not shown) for the wire-wrap posts 22 are printed on the disc 24 adjacent to the apertures 26 by a silk-screen process.

The apertures 26 are dimensioned to provide a tight fit between their walls and the wire-wrap posts 22 and provide precise location ofthe posts and in conjunction with the apertures in the resilient dielectric support 12 ensure accurate "line up" of the contact-posts which could otherwise be skewed and/or "hedgehogged".

The disc 24 is secured by adhesion to the potting compound 28 or by an adhesive in the recess 30 at the rear end of the shell.

Referring to Figure 2, this shows a second (female) part of a two-part electrical connector having all the features recited above with reference to Figure 1 with the exception that the connector contacts are sockets 18 instead of pins and the resilient dielectric support 12 is formed to have a ramped circumferential shoulder 23 and is located in the shell 10 by abutment of this shoulder against a corresponding circumferential shoulder 27 on the inside of the shell 10 and is further secured by a layer of adhesive (not shown). In order to assemble one part of an electrical connector as shown in Figure 1 or Figure 2 the resilient dielectric support 12 is first inserted, by use of an inserting tool (not shown), into the shell 10 and secured therein by a layer of adhesive (not shown).

The connector contacts 16 or 18 are then inserted in the support 12 from the rear of the connector. An alignment jig (not shown) is used in conjunction with the shell during this operation. The jig is arranged to limit the penetration of the contacts 16 or 18 into the support 12 and takes the form, in the case of the connector-part shown in Figure 1, of a plate that the pins 16 contact when they have penetrated the support 12 to the desired extent or, in the case of the connector-part shown in Figure 2, a plate with pegs that locate the sockets 18 and similarly limit their degree of penetration through the support 12. The space within the shell 10 to the rear of the resilient dielectric support 12 is then filled with a potting compound, which may be, for example, an epoxy compound or a room-temperature vulcanising material, in its liquid form. The interference fit provided by the portions 20 of the contacts 16 or 18 against the walls of their associated apertures 13 prevents any potting compound from leaking past the resilient dielectric support 12. The rigid dielectric support disc is then fitted to the shell 10, it being located circumferentially by engagement of the peg 32 in the notch 34, and secured by adhesion to the potting compound. Further adhesion may be provided by a layer of adhesion in the recess 30. When the potting compound has hardened the alignment jig is withdrawn from the front of the shell.

New claims or amendments to claims filed on 5th June1980 New or amended claims:

Claims (12)

1. One part of a two-part, multi-contact, electrical connector, wherein each contact has a wire-wrap terminal post, projecting rearwardlytherefrom,the contacts each being an interference fit in respective apertures in a resilient dielectric support which is an interference fit in the shell of the connector and being further supported by a mass of potting compound in the shell rearwardly of the dielectric support, the terminal posts projecting through apertures in a fixed rigid dielectric disc mounted rearwardly of the potting compound with the walls of the apertures closely fitting the respective terminal posts, the disc serving to locate the terminal posts and substantially to prevent twist of the forward ends of the posts during subsequent wire-wrapping operations.

2. A method of making one part of a two part, multi-contact, electrical connector, including the steps of providing a rigid shell, inserting a resilient dielectric contact-support into the shell, the support having a plurality of apertures therethrough and being an interference fit in the shell, inserting a contact into each aperture in the support, the contacts being longitudinally aligned with one another and with the aid of a jig, each contact being an interference fit in its aperture in the support and having a wire-wrap terminal post projecting rearwardlytherefrom beyond the rear of the shell, potting the contacts in the shell to the rear of the support in liquid potting compound, closing the rear of the shell with a rigid dielectric disc having in it apertures through which the wire-wrap posts pass and which closely fit the wire-wrap posts, and allowing the potting compound to set.

3. One part of a two part electrical connector, wherein the or each contact has a wire-wrap terminal post of non-circular cross-section projecting rearwardly therefrom, each contact being received in a respective aperture in a resilient dielectric support which fits in the shell of the connector, and each terminal post projecting through a respective aperture in a rigid dielectric disc secured against rotation and mounted rearwardly of the dielectric support with the wall of the aperture closely fitting the terminal post, the disc serving to locate the terminal post and to resist twist of the post during a subsequent wire-wrapping operation.

4. A connector according to claim 3, in which each contact is an interference fit in the respective aperture in the dielectric support.

5. A connector according to claim 3 or 4, in which the dielectric support is an interference fit in the shell of the connector.

6. A connector according to claim 3,4 or 5, including a mass of potting compound in the shell rearwardly of the dielectric support.

7. A connector according to claim 7, in which the rigid disc is mounted rearwardly of the pottingcom- pound.

8. A connector according to any of claims 1 and 3 to 7, in which each contact is integrally formed with its wire-wrap terminal post.

9. A connector according to any of claims 1 and 3 to 8, in which the wire-wrap post is of square crosssection.

10. A connector according to any of claims 1 and 3 to 9, in which the rigid dielectric disc is secured.

against rotation by a peg engaging in a notch at its periphery.

11. One part of a two-part electrical connector, substantially as herein described with reference to the drawing.

12. A method of making one part of a two-part electrical connector, substantially as herein described with reference to the drawing.