WO2008010020A1

WO2008010020A1 - Electrical connector having a secondary locking member

Info

Publication number: WO2008010020A1
Application number: PCT/IB2006/003471
Authority: WO
Inventors: Frédéric CHAZOTTES; Christian Campfort
Original assignee: Fci
Priority date: 2006-07-18
Filing date: 2006-07-18
Publication date: 2008-01-24

Abstract

This connector comprises an insulative housing (3) having at least one terminal accommodating chamber (5) , a lateral wall (7) adjacent said chamber, wherein an axially extending opening (19) is formed, and a flexible arm (11) provided to secure a suitable terminal (15) in the chamber, and - a secondary locking member (25) having a locking wall (29) corresponding to the opening (19) , for engaging the flexible arm (11) and blocking the latter in flexion. The housing (3) has a projection (21) axially extending from the lateral wall (7) in the opening (19) over a part of the length of the flexible arm (11) , the projection (21) and the arm (11) defining therebetween a recess (23) engageable by the locking wall (29) in the locking position.

Description

ELECTRICAL CONNECTOR HAVING A SECONDARY LOCKING MEMBER

BACKGROUND OF THE INVENTION

The invention relates to an electrical connector comprising

- an insulative housing having at least one terminal accommodating chamber, a lateral wall adjacent said chamber, wherein an axially extending opening is formed, whereby the chamber is laterally open on a part of its length, and a flexible arm essentially axially projecting from said wall into the chamber and provided to secure a suitable terminal in the chamber, said arm at least partly extending in correspondence with said opening and being deflectable into said opening, and

- a secondary locking member having a locking wall corresponding to the opening, said secondary locking member being mountable on the housing into a locking position, wherein the locking wall at least partially closes said opening and engages the flexible arm thereby blocking said arm in flexion.

Connectors of this type are known in the art. The openings formed in the housings of such connectors are generally provided to make the moulding easier and to minimize the size of the connectors.

However, it has been noted that applying a withdrawal effort on a terminal once secured in the corresponding chamber may produce a substantial deformation of the locking wall. Depending on the effort applied, it may be possible that the rigidity of the wall is not sufficient for the wall to properly prevent the terminal from being forced out the chamber. Further, depending on the precision in the moulding of the secondary locking member, a lack of planarity of the locking wall can make that this locking wall does not correctly engage all the flexible arms.

SUMMARY OF THE INVENTION

It is an object of the invention to provide an electrical connector of the above type, providing an increased retention effect for the terminals accommodated in the chambers with no substantial modification of the existing moulds or additional complexity.

Accordingly, the invention provides an electrical connector of the above-mentioned type, wherein the housing has a projection axially extending from the lateral wall in the opening over a part of the length of the flexible arm, the projection and the arm defining therebetween a recess engageable by the locking wall in the locking position of the secondary locking member.

The invention will be better understood on reading the following description of one particular embodiment of the invention, given as a non-limiting example.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an exploded perspective view, from the front side, of the housing of an electrical connector according to the invention;

Fig. 2 a perspective view, from the rear side, of the secondary locking member of an electrical connector according to the invention; Fig. 3 and Fig. 4 are sectional views of the connector, the housing and the secondary locking member of are shown respectively on Fig. 1 and Fig. 2, in an axial plane along the 3-3 direction, with the locking member respectively in the pre-mounted position and in the locking position.

DETAILED DESCRIPTION OF ONE PREFERRED EMBODIMENT

A connector 1 according to the invention is shown on Figures 3 and 4.

In the example shown, the connector 1 is a female terminal-holder of a type used in an automotive application.

Such a connector is suitable to mate with a counterpart connector including complementary male terminals. However, the invention may apply to different connector types.

For the sake of clarity, the Figures are orientated according to an X-axis, which represents the mating direction of the connector 1 with the counterpart connector

(not shown) . The X-axis is supposed to be orientated from the connector 1 towards the counterpart connector in mating conditions . Every direction- or orientation-related term in the following description, in particular the terms "rear" and "front", should be interpreted as referring to this axis.

In this respect, the connector 1 has a front side 2 corresponding to the mating side. As shown on Figures 1, 3, and 4, the connector 1 has an insulative housing 3 made of a plastic material and formed with a plurality of terminal accommodating chambers 4, 5, 6.

In the example shown, the chambers 4 are provided to accommodate power terminals whereas the chambers 5, 6 have smaller dimensions and are designed to accommodate signal terminals. The chambers 5, 6 of the connector 1 are disposed in several parallel rows, more precisely in two outer rows of chambers 5 and two inner rows of chambers 6. The housing 3 substantially has a parallelepiped shape with peripheral axial walls 7, 8 including a pair of opposed parallel lateral walls 7, and a pair of opposed parallel transversal walls 8. Each lateral wall 7 extends adjacent a respective outer row of chambers 5 and delimits said chambers .

The housing also has a front face 9 formed with through passages communicating with the chambers 4, 5, 6 for insertion of respective male terminals suitable to mate with the female terminals accommodated in the chambers.

Locking projections 10 are provided on the transversal wall 8 to be engaged by a complementary snap-fit securing members .

Referring especially to Fig. 3 and 4, it can be seen that the housing 3 is formed with flexible arms 11, 12 associated with respective chambers 5, 6, said flexible arms

11, 12 being provided to secure suitable terminals 15 in the corresponding chambers 5, 6, by snap-fit effect.

On the Fig. 3 and 4, two terminals 15 are shown in their service position, wherein they are fully engaged in the respective chambers 5, 6 and secured therein by the respective flexible arms 11, 12.

Each of the flexible arms 11 associated with the chambers 5 projects forwards and essentially axially from the adjacent lateral wall 7 into the corresponding chamber 5. The arm 11 is a cantilevered arm with a free end at the front side thereof, and a base section 16 which connects the arm 11 to the wall 7. The arm 11 further comprises a tooth 17 providing a stop member for engaging a rear edge of the terminal 15 as shown on Fig. 3 and 4.

The lateral wall 7 is formed with through openings 19 corresponding to respective chambers, each of said opening 19 axially extending from the base 16 of the arm 11 to the front end of the chamber 5. The chamber 5 is thus laterally open on a part of its length and the flexible arm 11, which extends in correspondence with the opening 19, can be deflected into the opening upon the insertion of the terminal in the chamber 5. The housing 3 further comprises a tab 21 axialIy projecting in the opening 19 from the wall 7 at the base 16 of the arm 11, over a part of the length of said arm 11. In the example shown, the tab 21 extends over the half length of the arm 11. The tab 21 and the arm 11 in its operative position (i.e. when snap-fitted with the terminal to secure the latter in the accommodating chamber) define a recess 23 therebetween, which is open at the front side.

The housing 3 is integrally made by moulding from a plastic material. As shown on Fig. 2-4, the connector 1 also comprises a secondary locking member 25, which is also preferably made as one piece moulded from a plastic material.

The secondary locking member 25 is formed as a cap, having a front plate 27 and two opposed lateral locking walls 29 rearwards projecting from said plate.

The front plate 27 is formed with through passages 31 arranged in correspondence with the respective chambers 4, 5, 6.

The locking walls 29 are provided with internally formed axial fingers (or ribs) 33 corresponding to respective openings 19, each having a free end 35 at the rear side thereof, opposed to the front plate 27. The free ends 35 of the fingers are designed to be engageable in the respective recesses 23. The secondary locking member 25 is adapted to be mounted on the housing 3, from the front mating side thereof, by sliding in the axial direction X. When mounted on the housing 3, the locking member 25 is axially slideable between a pre-mounted position (illustrated on Fig. 3) and -a fully engaged locking position (illustrated on Fig. 4) .

To this purpose, the secondary locking member 25 has snap-fit securing members 37 formed on both transversal sides thereof as resilient arms, for securing the locking member 25 on the housing 3 in the locking position by engaging the respective locking projections 10. The secondary locking member 25 and the housing 3 are also provided with complementary stopping means (not shown) for provisory stopping the locking member 25 on the housing 3 in the pre-mounted position.

As shown on Fig. 3, in the pre-mounted position of the locking member 25, the front plate 27 is axially spaced apart from the front face 9 of the housing 3. The fingers 33, and more generally the locking wall 29, are spaced apart from flexible arms 11, whereby said arms 11 can be deflected. In this position of the locking member 25, terminals can thus be inserted in the chambers wherein no terminal is accommodated, and the locking member does not provide any additional retention force to the one provided by the arm 11, where a terminal is accommodated in the corresponding chamber.

As shown on Fig. 4, in the operative position (or locking position) of the locking member 25, the front plate 27 engages the front face 9 of the housing. Correspondingly, the fingers 33 come into engagement with the respective arms 11, thereby preventing the arms from deflecting and disengaging from the respective terminals 15.

In this position, the fingers 33, and more generally the locking wall 29, partially close the corresponding openings 19 thereby providing a closing wall to the chambers 5. The free ends 35 of the fingers 33 engage the respective recesses 23 and thus provide a wedge effect substantially increasing the resistance to deformation in flexion of the arms 11.

In the case where a terminal 15 is attempted to be forced out of the chamber 5, for example by applying a withdrawal force to the corresponding cable, the wedge effect provides an additional resistance to the flexion of both the locking wall 29 and the arm 11. The arm 11 thus cannot be deflected and the terminal 15 cannot be withdrawn from the chamber 5 unless a sufficient force is exerted to break the arm 11.

It will be appreciated that in some prior art connectors, the locking wall could be deformed in flexion together with the arm in such an extent that the terminal could be forced out of the chamber, under a withdrawal force of a relatively low intensity.

The invention provides a wedge effect which substantially increases the retention force on the terminals, by simple means which do not involve complex manufacturing processes.

Claims

1. Electrical connector comprising

- an insulative housing (3) having at least one terminal accommodating chamber (5) , a lateral wall (7) adjacent said chamber, wherein an axially extending opening (19) is formed, whereby the chamber (5) is laterally open on a part of its length, and a flexible arm (11) essentially axially projecting from said wall (7) into the chamber (5) and provided to secure a suitable terminal (15) in the chamber, said arm (11) at least partly extending in correspondence with said opening (19) and being deflectable into said opening, and

- a secondary locking member (25) having a locking wall (29) corresponding to the opening (19) , said secondary locking member (25) being mountable on the housing (3) into a locking position, wherein the locking wall (29) at least partially closes said opening (19) and engages the flexible arm (11) thereby blocking said arm in flexion, characterized in that the housing (3) has a projection (21) axially extending from the lateral wall (7) in the opening (19) over a part of the length of the flexible arm (11) , the projection (21) and the arm (11) defining therebetween a recess (23) engageable by the locking wall (29) in the locking position of the secondary locking member (25) .

2. Electrical connector as claimed in claim 1, characterized in that said secondary locking member (25) is adapted to be slideably mounted on the housing (3) in an axial direction (X) from a front mating side (2) of the connector.

3. Electrical connector as claimed in claim 1 or 2, characterized in that said locking member (25) and said housing (3) have complementary securing means (10, 37) for securing the locking member (25) on the housing (3) in the locking position, and complementary stopping means for provisory stopping the locking member (25) on the housing (3) in a pre-mounted position, wherein the locking wall (29) is spaced apart from the flexible arm (11) , whereby said arm can be deflected.

4. Electrical connector as claimed in claim 3 , characterized in that the locking member (25) is axially slideable on the housing (3) between the pre-mounted position and the locking position.

5. Electrical connector as claimed in anyone of claims 1 to 4, characterized in that the housing (3) is integrally made by moulding from a plastic material.