The present invention relates generally to an electrical connector assembly, more particularly to an electrical connector for use in a supplemental inflatable restraint (SIR) system for the protection of vehicle occupants.

It is known to mount an air bag of a SIR system in a vehicle, the air bag inflation being triggered by a device known as an initiator. The initiator is connected to an electrical connector which is operatively coupled to a pair of wires leading from a controller. An example of such a connector is disclosed in US6217388B1. This document discloses a connector assembly comprising a connector housing with a plug portion, a pair of terminal fittings mounted in the connector assembly and crimped to a pair of wires, and a connector position assurance (CPA) device.

Although the patent '388 discloses a good electrical connector, it still has some deficiencies. The number of parts necessary to build the connector makes the assembly relatively complex. Additionally, the construction disclosed in this document is not convenient when it is required to have a connector with a cable outlet parallel to the mating axis of the plug portion, the terminal fittings being substantially parallel to the pair of wires. WO9741623 discloses a connector with a lateral cable outlet. US5788534 discloses a connector with a clamping mechanism.

It is an object of the present invention to solve the above mentioned problem and to provide an improved electrical connector assembly. According to the invention, it is provided an electrical connector assembly comprising a connector housing configured to receive at least one terminal fitting attached to the free end of an electrical wire, characterized in that the electrical connector assembly further comprises a holder which is mounted onto the connector housing for holding the terminal fitting in the housing, said holder having:

• locking means which cooperates with complementary locking means provided on the connector housing in order to retain the holder in a locked position onto the connector housing,
• a first clamping surface which cooperates with a second clamping surface provided on the connector housing in order to clamp a portion of the electrical wire when the holder is in its locked position,

• said complementary locking means provided on the connector housing includes a flexible arm and in that said second clamping surface is located on an inner side of the flexible arm;
• said second clamping surface is constituted of a flange extending along a transverse axis with regards to the mating axis;
• the flexible arm has a cam surface against which a portion of the terminal fitting is sliding during its insertion into the housing in order to bias the flexible arm outwardly;
• the holder locking means includes a retaining lug which cooperates with a complementary detent latch portion provided on the flexible arm in order to retain the holder in the locked position.

Thanks to the invention, only two steps are necessary for attachment of the terminal fitting to the connector assembly. Firstly the terminal fitting is inserted in the connector housing and then the holder is mounted on the connector housing. Thus, the manufacturing and assembly of the connector according to the invention are made easier and more reliable with a limited number of parts.

According to other features of the present invention:

• the terminal fitting comprises a ferrite block which is fitted into the connector housing, and said clamping surfaces are arranged above the ferrite block when the terminal fitting is received in the connector housing and the holder is in its locked position;
• said holder comprises an axial portion forming a cover substantially parallel to an axial casing portion of the connector housing, and the cover comprises a wire slot for receiving a portion of the electrical wire, said portion of the electrical wire being clamped between the bottom of the wire slot and the second clamping surface;

• said electrical connector assembly is configured to receive a terminal fitting with only two electrical wires, and said retaining lug extends between the two electrical wires;
• the connector is of a straight type, the mating axis of the connector being substantially parallel to the drawing direction of the corresponding electrical wire, and the holder is slidably mounted onto the connector housing along a mounting direction which is substantially orthogonal to the mating axis, from a removed position to its locked position;
• a connector position assurance device is axially mounted on the connector housing through a portion of the holder.

The present invention is now described by way of example with reference to the accompanying drawings in which:

• figure 1 is an exploded perspective view showing a connector assembly according to the present invention having a connector housing and a holder for retaining a terminal fitting;
• figure 2 is a perspective view showing a first step of the assembly of the connector of figure 1 wherein the terminal fitting is to be inserted in the connector housing and is bending a flexible arm outwardly;
• figure 3 is a view similar to the one of figure 2 showing a second step of the assembly wherein the terminal fitting is inserted in the connector housing;
• figure 4 is a view similar to the one of figure 2 showing a third step of the assembly wherein the holder is about to be slidably mounted towards an axial casing portion of the connector housing;
• figure 5 is a view similar to the one of figure 2 showing the connector housing with the holder in locked position holding the terminal fitting in the housing.

An exemplary embodiment of a connector assembly 10 according to the teaching of the present invention is shown on figure 1 to 5.

In the present description, axial, radial, transverse will be used in connection with the connector parts, with reference to the connector mating axis A1. In a non-limitative purpose, the connector mating axis A1 is orientated vertically along with the orientation of figure 1.

The connector assembly 10 includes a connector housing 12 comprising a frame portion 14, a substantially cylindrical plug portion 16 extending downwardly from the frame portion 14, along the connector mating axis A1, for connection with a corresponding counterpart connector (not shown), and a substantially axial casing portion 18 extending upwardly from the frame portion 14.

The connector housing 12 is configured to receive a terminal fitting 20 having here two parallel axial terminals 24, 26 inserted into respective holes 28, 30 of the frame portion 14, and extending axially in the plug portion 16 for electrical connection. The axial terminals 24, 26 are connected to respective wires 32, 34 through an electronic interference damping device in the form of a ferrite block 36 which has two through holes 38, 40 for the insertion of the lower free ends of the wires 32, 34.

In the embodiment shown, the ferrite block 36 comprises a casing of substantially oblong cross section with an upper transverse surface 42 and a lower transverse surface 44 of oblong shapes connected by an axial wall 46.

The connector assembly 10 is preferably of the straight type, meaning the cable outlet, or wire outlet, is substantially parallel to the mating axis A1.

A holder 48 is mounted onto the connector housing 12 in order to hold the terminal fitting 20 in position. The holder 48 comprises a bottom portion forming a sliding portion 50 which is provided with two opposing parallel inner grooves 52, 54 on its bottom face in order to slidably cooperate with two corresponding opposing guiding surfaces 56, 58 on the frame portion 14. The sliding movement of the holder 48 on the frame portion 14 allows snap-fitting assembly of the holder 48 with the connector housing 12 along a snap-fitting transverse axis A2 which is substantially perpendicular to the mating axis A1.

For the purpose of snap-fitting assembly, the holder 48 and the frame portion 14 are provided with complementary locking means including lateral locking lugs 60, 62 cooperating with lateral locking apertures 64, 66 to retain the holder 48 in a locked position, as shown in figure 5.

The holder 48 comprises an axial portion 68 forming a cover which is fitted to the axial casing portion 18 such that the ferrite block 36 is enclosed between the cover 68 and the axial casing portion 18 when the holder 48 is in its locked position.

Advantageously, a first pair of locking apertures 64 is located on the sliding portion 50 lateral walls, complementary with a first pair of locking lugs 60 located on the frame portion 14 lateral walls, and a second pair of locking apertures 66 is located on the axial casing portion 18 lateral walls, complementary with a second pair of locking lugs 62 located on the cover 68 lateral walls.

Advantageously, an upper part of the axial casing portion 18 is provided with a retention portion in the form of a flexible arm 70, or beam. According to the embodiment shown, said flexible arm 70 is constituted of a beam extending substantially transversally, perpendicularly to the snap-fitting axis A2, between the two lateral walls of the axial casing portion 18. Said flexible arm 70 is able to bend elastically outwardly, in an opposite direction to the cover 68 along the snap-fitting axis A2, when the terminal fitting 20 with the ferrite block 36 is inserted into the connector housing 12. The flexible arm 70 is provided on its inward side with a detent latch portion 71 having an upper slanted cam surface 72 which is able to cooperate with the lower transverse surface 44 of the ferrite block 36 in order to bend the flexible arm 70 outwardly, from a rest position, shown on figures 3 to 5, to a bent position, shown on figure 2.

The cover 68 has a first clamping surface 74 which cooperates with a second clamping surface 76 located on the flexible arm 70, here on the detent latch portion 71, in order to clamp retained portions of the wires 32, 34 right above the ferrite block 36, when the holder 48 is in its locked position, as shown on figure 5.

According to the embodiment shown, the second clamping surface 76 is constituted of a flange located radially on the inner side of the detent latch portion 71. Advantageously, the upper portion of the cover 68 has two wire slots 78, 80, or notches, for receiving the two retained portions of the wires 32, 34. The bottom of each wire slot 78, 80 forms a portion of the first clamping surface 74 such that, in the locked position of the holder 48, the retained portions of the wires 32, 34 are blocked into the wire slots 78, 80 under elastic pressure from the second clamping surface 76.

Advantageously, the upper portion of the cover 68 is provided with an elastic retaining lug 82 extending radially outwardly along the snap-fitting axis A2 towards the detent latch portion 71 in order to retain the holder 48 in the locked position. Said detent latch portion 71 and said retaining lug 82 have complementary cooperating locking surfaces allowing snap-fitting of the two parts together which helps maintaining the clamping force on the retained portions of the wires 32, 34. In the locked position, the retaining lug 82 extends above the ferrite block 36, between the two wires 32, 34, and the outer free end of the retaining lug 82 is received in a complementary locking notch 84 arranged in the axial casing portion 18, below the detent latch portion 71.

It has to be noted that, when the terminal fitting 20 is in position and the holder 48 is in its locked position of figure 5, the retained portion of the cables 32, 34 is pulled transversely along the snap-fitting axis A2 ensuring good retention of the cables 32, 34.

According to the embodiment shown, a connector position assurance (CPA) device 86 is axially mounted on the connector housing 12 through the sliding portion 50 of the holder 48. The CPA device 86 will not be described in details as it is a conventional device in the field of connector assemblies.

The assembly of the connector assembly 10 according to the invention will now be described in connection with figures 2 to 5.

First the terminal fitting 20 connected to the wires 32, 34 is brought downwardly along the mating axis A1 towards the connector housing 12 in order to insert the terminals 24, 26 into the corresponding holes 28, 30 of the frame portion 14, and in order to have the ferrite block 36 received in a corresponding receptacle of the connector housing 12. During axial insertion of the terminal fitting 20, the lower surface 44 of the ferrite block 36 comes into abutment against the cam surface 72 which biases the flexible arm 70 outwardly, as shown in figure 2. Alternatively, a tool could be used to bend the flexible arm 70 outwardly in order to allow insertion of the ferrite block 36 along the mating axis A1.

At the end of the terminal fitting 20 insertion, the terminals 24, 26 are fully received within the corresponding holes 28, 30, and the flexible arm 70 has gone back to its rest position, as shown in figure 3.

Then the holder 48 is fitted to the connector housing 12 by sliding its sliding portion 50 along the snap-fitting axis A2 towards the axial casing portion 18, as shown in figure 4, until the holder 48 reaches its locked position shown in figure 5, wherein all the locking lugs 60, 62 are received in their locking apertures 64, 66, and wherein the retaining lug 82 is received in its locking notch 84 and snap-fitted to the detent latch portion 71. In the locked position, the retained portions of the wires 32, 34 are clamped between the clamping surfaces 74, 76.