GB2314696A

GB2314696A - Connector with strain relief means

Info

Publication number: GB2314696A
Application number: GB9713259A
Authority: GB
Inventors: Chrystostomos Pet Chrysostomou
Original assignee: Whitaker LLC
Current assignee: Whitaker LLC
Priority date: 1996-06-24
Filing date: 1997-06-23
Publication date: 1998-01-07
Anticipated expiration: 2017-06-23
Also published as: GB2314696B; GB9713259D0; GB9613178D0

Abstract

An IDC connector (2) comprises IDC terminals mounted in an insulative housing that is surrounded by an outer support housing (8). A cover (10) is provided with strain relief members for pinching insulated conducting wires (3) in grooves (44) of the support housing (8). The strain relief members are provided with tapered faces against which retention members (46) of the support housing (8) are swaged. The latter enhances pressure of the strain relief members against the wires and ensures secure and robust locking of the strain relief members and cover.

Description

CONNECTOR WITH WIRE STRAIN RELIEF MEANS This invention relates to a connector with strain relief means for securing conducting wires to the connector.

Insulation displacement contact (IDC) connectors typically comprise an insulative housing having IDC terminals mounted therein, the terminals having slots for receiving insulated conducting wires therein. Edges of the slot cut through the outer insulating layer and contact the inner conducting strands of the wires. IDC connectors thus enable interconnection between conductors and terminals to be effected in a particularly costeffective and rapid manner, as wires merely have to be stuffed into the IDC slots of terminals. One of the disadvantages of IDC connections, however, is the limited mechanical strength of the connection and limited current carrying capacity in comparison to crimped connections.

It would be desirable, in particular for certain applications where high reliability is required (e.g. in automotive safety features such as airbag ignition devices), to provide more robust and secure IDC connectors. tt would further be desirable to provide such connectors in a simpler and more cost-effective design.

An object of this invention is to provide a robust, secure and reliable connector.

Objects of this invention have been achieved by providing the connector according to claim 1. Plastic deformation of the connector support structure to maintain the connector cover securely in the locked position, ensures robust and reliable connection of wires to the connector. In particular, a high pulling force on the wires is enabled.

An embodiment of this invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is an isometric view of a connector according to this invention with the cover disassembled; Figure 2 is an exploded isometric view of part of the connector according to this invention, showing the terminal receiving housing and an IDC terminal; Figure 3 is an isometric view towards a bottom face of a cover of the connector according to this invention; Figure 4 is an isometric view of the connector with conducting wires about to be terminated thereto; Figure 5 is an isometric view of the connector with cover assembled; and Figure 6 is an isometric view of the fully assembled connector.

Referring to Figures 1-3, an IDC connector 2 is shown comprising an insulative terminal receiving housing 4, IDC terminals 6, an outer support housing 8, and a cover 10.

The outer housing 8 could be part of a device such as an automotive airbag gas generator, and could be made of metal.

The terminal receiving housing 4 comprises terminal receiving cavities 12 extending from a connection end face 14 to a mating face 16. Projecting beyond the connection end face 14, are walls 18 for separating connection sections of adjacent IDC contacts. Also projecting beyond the connection end face 14, are wire guide walls 20 for guiding wires either side of the walls 18 for termination to the respective terminals 6.

The IDC terminal 6 comprises a contact portion 22 and an IDC portion 24. The terminal is stamped and formed from sheet metal. The IDC section 24 comprises a U-shaped base 26 having opposed side walls 28,29 joined by a base wall 30. A slot 32 extends from one wall 28 to the other wall 29 and is provided with insulation displacing contact slots 34 in each of the walls 28,29 for cutting through the outer insulating layer of conducting wires 3 when stuffed thereinto. The contact section 22 comprises a flat tab contact extending through the receiving cavities 12 beyond the mating face 16 for plugging connection to a complementary connector, or for insertion in an ignition chamber of an automotive airbag gas generator. The terminal 6 can either be stitched into the cavities 12 in an automated assembly procedure, or over-moulded by the housing 4. A bottom end 38 of the IDC walls 28,29 rests upon the connection end face 14 for support thereagainst, particularly during termination with wires 3. The wire guide walls 20 provide a ledge 40 extending beyond the separation walls 18 for supporting the walls 28,29 from buckling or bending out of their planes.

The outward support housing 8 is in the form of a wall surrounding the terminal receiving housing 4 and extending beyond the connection end face 14 thereof, to a wire receiving end 42. The support housing 8 comprises wire receiving grooves 44, on opposing sides aligned with the wire receiving slots 32 of the terminals, for receiving the wires 3 thereacrossy as shown in Figure 4.

Adjacent grooves 44 are separated by cover retention members in the form of deformable walls 46. A pair of walls 46 are separated by a slot 47 running parallel to the grooves 44. The support housing 8 further comprises cover retention members in the form of latching shoulders 48 for engaging retention members in the form of latches 50 of the cover 10.

The cover 10 comprises a base wall 52 from which extend on opposing sides the resilient latches 50. The cover 10 further comprises strain relief members 54 receivable in grooves 44 of the support housing 8. On an opposing edge of the cover to the retention members 54, are plug portions 56 for insertion in the grooves 44.

The support housing 8 and terminal receiving housing 4 are symmetrical, and conducting wires 3 can be terminated to the terminals 6 mounted in the housing 4 from either side; in other words extending through the wire-receiving grooves 44 of the support housing 8 from one end, or from the opposing end. In the embodiment shown, the wires 3 are connected at their ends 5 to the connector 2, and therefore the cover 10 is not symmetrically designed i.e. on one side there are strain relief members 54 and on the other side plug portions 56.

The strain relief members 54 comprise a lower strain relief surface 60 provided with ribs 62 extending transversely to the direction of the wire for digging into the insulation to enhance the strain relieving effect.

Strain relief members 54 are separated by a gap 64 between which the groove separating walls 46 are received. The slot 64 is defined by opposed faces 66 whereby a portion 68 of the face 66 is tapered. The taper is arranged such that the slot 64 has a funnel shape extending inwardly towards the strain-relieving surface 60.

Termination of wires 3 to a connector is effected as shown in Figures 4-6. First, the wires 3 are positioned above the terminal slots 32 which are also aligned with the support housing grooves 44. Subsequently, the wires are depressed into the IDC slots 34 until abutment of the wires 3 with the bottom of the grooves 44 of the support housing 8. As shown in Figure 4, ends 5 of the wires 3 partially extend into grooves 44 positioned on the opposing side to the grooves from which the wires enter the connector. As shown in Figure 3, the cover 10 has corresponding groove portions 57 formed within the plug portions 56 for receiving the end portions 5 of the wires that lie within the grooves 44. The cover 10 is then positioned over the support housing 8 and latched into position where the latches 50 cooperate with the shoulders 48. During latching, the cover strain relief members 54 compress the wires 3 within the grooves 44. On the other side, the plug portions 56 close the ends of the grooves 44 such that the wire ends 5 are insulated from the exterior of the connector.

The support housing strain relief walls 46 are then deformed as shown in Figure 6, such that they abut the tapered surfaces 68 of the cover strain relief members 54.

This abutment causes the strain relief members to be further depressed against the wires 3. Compression of the wires is thus increased and simultaneously the cover is securely and robustly locked to the support housing 8. A secure and reliable IDC connection is thus ensured in a design that enables simple assembly procedures. In particular, a very robust strain relief is provided.

Claims

1. A connector for termination to conducting wires, comprising terminals assembled within a support housing and having connection sections for termination to the wires, the housing having grooves enabling access of the wires from externally of the connector to the connection sections, and a cover securable to the housing and having strain relief members for engaging the wires in the grooves and retaining the wires to the connector, the housing having plastically deformable retention means engageable with the cover for enhancing pressure of the strain relief members on the wires.

2. The connector of claim 1 wherein the retention means comprises a retention member for deformably engaging each strain relief member.

3. The connector of claim 2 wherein each strain relief member comprises a tapered surface engageable by the cooperating retention member.

4. The connector of claim 3 wherein the tapered surfaces of adjacent strain relief members form a funnel shape that receives therebetween a pair of deformable walls comprising the retention members, the walls being swaged apart against the opposed tapered surfaces.

5. The connector of any one of the preceding claims wherein the terminals are mounted to an insulative terminal receiving housing as an assembly, such assembly being surrounded by the support housing.

6. The connector of claim 5 wherein each terminal comprises an IDC connection portion having a pair of slotted walls with insulation cutting edges for cutting through insulation of a wire and contacting the inner conducting strands of the wire.

7. A connector for termination to conducting wires, constructed and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.