Connector members

Abstract: A connector member (1) for use in connecting electrical wiring is receivable in another connector part and has a housing body (2) having a plurality of passages for receiving metal wiring terminals (4). In a recess (6) of the body (2) having opposed side walls (25), there is a resilient locking arm (7) having a head portion (18). The locking arm (7) locks in use with another connector part. These are gaps between the head portion (18) and the side walls (25). A terminal retainer (3) is mounted on the body (2) and is locatable in a locking position in which it locks the metal terminals (4) in place. To prevent a wire or other foreign body being trapped in the gaps between the arm (7) and the side walls (25), the terminal retainer has a pair of gap blocking portions (23) which, in its locking position, lie on opposite sides of the head portion (18) of the locking arm (7) so as to at least partially block these gaps.

Description: BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION This invention relates to connectors for connecting electrical wiring, and in particularly to a connector member which is adapted to house metal terminals which are to be connected to terminals in another connector member. The connector member has at least one terminal retainer to lock the terminals in position, and a locking arm which in use locks the connector member to another connector part. 2. DESCRIPTION OF THE PRIOR ART A connector member of this type equipped with terminal retainers is shown in JP-A-8-287992. The connector is composed of a connector housing body and two terminal retainers. On one face of the housing body, there is a resilient locking arm for locking the connector member in position in a complementary connector part which is in the form of a housing receiving the connector member. This locking arm is partly located in a recess which is formed at the central part of the upper face of the housing body, and is designed not to protrude from the housing body more than required. Gaps are present between the locking arm and the side faces of the recess. These gaps permit a smooth fitting motion at the time of fitting with the receiving connector part, by receiving a pair of protruding guide walls which are formed in the receiving connector part. However, these gaps allow the possibility of the invasion of foreign articles, particularly the trapping of a wire during assembly of the connector. There is a risk of lifting of the locking arm if a wire is trapped beneath it, which would prevent proper functioning of the locking arm, and result in incorrect assembly of the connector. SUMMARY OF THE INVENTION An object of the present invention is to provide a connector member in which there the risk of trapping of a foreign article such as a wire or the like in gaps between a locking arm and a connector housing is reduced or avoided. According to the invention there is provided a connector member for use in connecting electrical wiring, as set out in claim 1. With the construction of the invention, since the gap blocking portions of the retainer block the gaps between the locking arm and the side walls of the recess when the retainer is installed on the connector housing body, the risk of trapping of foreign articles such as a wire or the like can be prevented or much reduced. The gap blocking portions may overlie the gaps between the locking arm, particularly the head portion of the locking arm, or may be at least partially located in the gaps. In one preferred embodiment the two gap blocking portions are mutually connected by a connection portion beneath the locking arm so that the strength of central part of the terminal retainer is improved. This is effective to prevent bending of the retainer at the time of molding the retainers and deformation at the time of use. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described by way of non-limitative example with reference to the accompanying drawings, in which:- Figure 1 is a perspective view of the parts of a first embodiment of the invention before the installation of the retainers on the connector housing body. Figure 2 is a perspective view of the connector of Fig. 1 after the installation of the retainers on the connector housing body. Figure 3 is a plan view of the connector member of Figs. 1 and 2. Figure 4 is a back view of the connector member of Figs. 1 and 2. Figure 5 is a perspective view of parts of a second connector member embodying the invention before the installation of the retainers on the connector housing body. Figure 6 is a perspective view of the connector member of Fig. 5 after the installation of the retainers on the connector housing body. Figure 7 is a plan view of the connector member of Figs. 5 and 6. Figure 8 is a back view of the connector member of Figs. 5 and 6. Figure 9 is a perspective view of parts of a third connector member embodying the invention before the installation of the retainers on the connector housing body. Figure 10 is a perspective view of the connector member of Fig. 9 after the installation of the retainers on the connector housing body. Figure 11 is a plan view of the connector member of Figs. 9 and 10. Figure 12 is a back view of the connector member of Figs. 9 and 10. DESCRIPTION OF THE PREFERRED EMBODIMENTS The first embodiment of the present invention is described referring to Figs. 1 to 4. The connector member 1 (female connector) is intended for use in the manner shown in JP-A-8-287992 discussed above, by insertion into a receiving housing part. It comprises the connector housing body 2 inside which the metal terminal fittings are in use located and two terminal retainers 3, 8, which are installed on the connector housing body 2. The connector housing body 2 is integratedly molded of a suitable synthetic resin material, and has terminal-receiving passages 5 in two rows at top and bottom, defined by walls 5A. The passages 5 are open at the back or rear face of the connector housing body 2 seen in Fig. 1. One metal terminal 4 on a wire W is shown by way of example in Fig. 1. These terminals 4 are inserted into the passages 5 so that the wire W protrudes (see Fig. 2). Resiliently deformable elements (not shown) which lock the terminals 4 in the passages in a latching manner are arranged on the inner wall faces of the passages 5 (wall faces which partition the passages at top and bottom) or on the terminals 4 themselves, in a known manner. Further, also in a known manner, there is a longitudinal rib (not shown) on a wall of each passage 5, which is received in a groove or slot (also not shown) of the terminal 4 when the terminal is inserted in the correct orientation. This prevents insertion of the terminal in the wrong way. At the front ends of the passages 5 are the apertures (seen in Fig. 4) through which opposing metal terminal fittings (not illustrated) are inserted, when the connector 1 is brought into engagement with a corresponding male connector (not illustrated). Upper and lower faces of the connector housing body 2 have retainer holes 17 into which the respective terminal locking bars 12 of the retainers 3, 8 enter. The holes 17 are at the central part of the passages 5 in the longitudinal direction. When the retainers 3, 8 are at the normal locking position (shown in Fig. 2), the respective terminal locking bars 12 project into the passages 5 through the retainer holes 17, engage the respective terminals 4 and, acting in addition to the resiliently deformable elements mentioned above, retain the terminals in place against accidental withdrawal. However, when the retainers 3, 8 are at the temporary position on the housing body 2 described below, the respective terminal locking bars 12 do not project into the passages 5 and permit the insertion (and if necessary extraction) of the terminals 4. A recess 6 open at the front and rear faces of the body 2 and also open upwardly is provided on the central part of the body 2 on its upper side. A locking arm 7 is arranged in the recess 6. The locking arm 7 extends rearwardly in a cantilever manner from its front end which is integral with the base of the recess 6. Gaps with nearly the same width are formed between the locking arm 7 and both side walls 25 of the recess 6. As described above, these gaps are necessary in order to receive a pair of walls on the receiving housing part (not illustrated) for guiding the engagement of the connector member 1 with the receiving housing part. These gaps also allow an operator's finger to depress the locking arm 7. An upward projection 18 is formed at the rear end of the locking arm 7. The locking arm 7 is resiliently depressed by pushing by an operator's finger on the projection 18 when the connector member 1 is fitted with and separated from the receiving housing part. A second projection 9 is located at the centre of the locking arm 7, and retains the connector member 1 in the receiving housing part by being received in a recess in the receiving housing. The rear end of the locking arm 7 is nearly in the plane of the rear face of the housing body 2 or is somewhat recessed from that face. The retainer holding recesses 14 at which the retainers 3, 8 are installed are located at both side faces of the housing body 2. Each retainer holding recess 14 has a triangular shape, and two protrusions 15, 26 project from its base wall. When only the temporary locking protrusion 15 at the rear is received in a slot 16 in side walls 19 of the retainer 3, the retainer 3 is at the temporary position. On the other hand, when the retainer 3 is pushed slidingly along the recess 14, its flexible side walls 19 bend to allow the second locking protrusion 26 to enter the slot 16. When both the locking protrusions 15, 26 are received in the slot 16, the retainer 3 is at the normal (full) locking position, with its locking bars 12 engaging the terminals 4 as described above. The terminals 4 which are installed in the passages 5 are each prepared by bending an electrically conductive steel plate, to form at the rear end a barrel part 10 in which the wire W is fixed, and at the front end the connecting parts 11 which connect in use with the opposed male terminals. Further, an opening 13 into which the terminal locking bars 12 of the retainers 3, 8 are inserted is arranged at a central part. The two retainers are the upper retainer 3 which is installed at the locking arm 7 side of the housing body 2 and the retainer 8 which is installed at the lower side which has no locking arm. The construction of the upper retainer 3 is described in detail, and the same reference numerals are given to corresponding parts of the lower retainer 8. The retainer 3, integrally molded in a suitable synthetic resin, is as mentioned installed on the upper face of the connector housing body 2 and locks with the terminals 4. Where the retainer 3 extends over the locking arm 7, it has a U-shape slot 20 having the same width as the recess 6 of the housing body 2. The two side parts 21 are connected by a connecting piece 22 at the rear side to define the slot 20. Two gap blocking projections 23° protrude rearwardly at the rear side of the connecting piece 22. When the retainer 3 is installed on the connector housing body 2 in its normal locking position, the connecting piece 22 is located just forwardly of the projection 18 of the locking arm and overlies the locking arm 7. The projections 23 are located on each side of the end part of the arm 7 at the gaps between the arm 7 and the side walls 25 of the recess 6 so as to overlie and thereby block these gaps. That is, the width of the projections 23 is equal to, or slightly greater than, the width of the gaps between the locking arm 7 and the side walls 25. When the retainer 3 is at the normal (full) locking position, the rear end positions of the projections 23 are nearly in the same vertical plane as the rear end of the locking arm 7, or are situated slightly in front of that plane. At this time, the discrepancy between the rear end of the locking arm 7 and the end of the projections 23 in the front to back direction is designed to be smaller than the diameter of the wire W, even in the case when the end of the projections is forward of the rear end of the locking arm. At the lower faces of the side parts 21 (the faces confronting the connector housing body 2), the terminal locking bars 12 corresponding to the passages 5 are located. From both sides of the retainer 3, the retainer side pieces 19 which project to overlap the sides of the connector housing body 2 are arranged to be resiliently deformable. The long slots 16 are in the retainer side pieces 19. As there is no locking arm 7 at the connector housing body 2 at the lower side, the retainer 8 is formed with a single sheet part 24. The terminal locking bars 12 are arranged at its upper side. The operation of the connector member of Figs. 1 to 4 is as follows. First, the retainers 3, 8 are put into the temporary position on the connector housing body 2. That is, the temporary locking protrusions 15 are fitted in the slots 16 by bending the retainer side pieces 19. Then, the metal terminals 4 are installed in the passages 5 of the connector housing body 2. The terminals 4 are locked a first time by the deformable projections (not shown) which are on the walls of the passages 5 (or alternatively on the terminals, as mentioned above). Next the normal locking protrusions 26 are fitted in the slots 16 by pressing the retainers 3, 8 towards the connector housing body 2 to reach the normal locking position. At this time, since the terminal locking bars 12 engage the openings 13 of the terminals 4 in the connector housing body 2, the terminals 4 are locked a second time. Further, on the upper side retainer 3, the projections 23 now block the gaps between the locking arm 7 and the side wall faces 25 of the recess 6 as seen in plan view. At the same time, at the normal locking position, the edge positions of the projections 23 are nearly in the same plane with the rear end of the locking arm 7, or situated slightly in front of that. As the degree of the discrepancy is smaller than the diameter of the electrical wire W, the wire W cannot go into these gaps. As the gaps are also at least partially blocked at the temporary locking position, the wire W cannot easily go into the gaps. Therefore, the risk of trapping foreign articles such as a wire or the like under the locking arm 7 can be reduced at both the normal and temporary locking positions, and accordingly, the permanent deformation or other problem caused by excessive lifting of the locking arm 7 by the wire W can be avoided. Next the second embodiment of the present invention is described referring to Figs. 5 to 8, in which the same reference numbers are used for parts corresponding to those of Figs. 1 to 4. Detailed description of these parts is therefore omitted. In this embodiment the gap blocking projections 30 at the rear edge of the retainer 3 protrude further downwardly as compared with the projections 23 in Figs. 1 to 4. The projections 30 block the gaps between the locking arm 7 and the side wall faces 25 in a similar manner but are inserted in the gaps when the retainer 3 is installed on the connector housing body 2 (see Fig. 6 and Fig. 8). This construction also has the same function and effect as the first embodiment. The third embodiment of the present invention is described referring to Figs. 9 to 12 in which the same reference numbers are used for parts corresponding to those of Figs. 1 to 4. Detailed description of these parts is therefore omitted. In this embodiment the connector housing body 2 has the same construction as in the second embodiment. However, the projection 40 at the rear edge part of the retainer 3 is formed by a pair of opposed arms 41 (which constitute gap-blocking portions) which extend downward on opposite sides of the locking arm 7 from the connecting piece 22. Further, a connecting piece 42 connects the pair of arms 41 at their lower ends. The locking arm 7 can be inserted in the aperture 43 which is surrounded by the four parts 22, 41, 41 and 42. However, when the connecting piece 42 is at the normal locking position, the operation of the locking arm 7 is not obstructed. This construction improves the strength of the central part of the retainer 3, as the arms 41 are mutually connected by the connecting piece 42. Therefore, bending at the insertion of the retainer 3 and its deformation in usage are effectively prevented. Such effects are particularly effective in the case in which there is risk of deformation when the retainer 3 is long when there are multiple poles of the connector. A connector equipped with a pair of retainers has been illustrated, but one having one retainer may be used and the retainer need not be a separate body from the connector housing body. The retainer may be in an integrated relationship with the connector housing body to which it is connected by hinges or the like.

Claims: A connector member for use in connecting electrical wiring, having a housing body (2) having a rear end and a front end and a first face extending from the rear end to the front end and a plurality of passages (5) for receiving metal wiring terminals (4) extending from said rear end towards said front end, a recess (6) in said first face having opposed side walls (25), a resilient locking arm (7) having a first end mounted on said housing body, an arm portion extending in cantilever manner from said first end and a head portion (18) which is remote from said first end and projects above said arm portion in the direction away from the base of the recess (6), said locking arm (7) being adapted to make locking engagement in use with another connector part, and said locking arm (7) being at least partly located in said recess (6) between said opposed side walls (25) thereof, with gaps between said head portion (18) and said side walls (25), and a terminal retainer (3) mounted on said housing body (2) so as to extend across said first face thereof, and locatable on said housing body in a locking position in which in use it locks in place any said metal terminals (4) which have been inserted in said passages (5) of said housing body, characterized in that said terminal retainer (3) has at its rearward end, a pair of gap blocking portions (23,30,41) which, at least in said locking position thereof, lie on opposite sides of said head portion (18) of said locking arm (7) so as to at least partially block said gaps between said head portion (18) of said locking arm and said side walls (25) of said recess, and wherein, when said terminal retainer (3) is in its locking position, the rear ends of said gap blocking portions are, with respect to a plane which is perpendicular to the front-to-rear direction of the connector member and lies at the rear end of the locking arm (7), positioned forwardly of said plane or nearly at said plane, whereby in use said gap blocking portions prevent a wire entering said gaps between said head portion (18) of said locking arm and said side walls (25) of said recess. A connector member according to claim 1, wherein said terminal retainer (3) has a bridge portion (22) overlying said locking arm in said locking position, said gap blocking portions (23) extending rearwardly from said bridge portion so as to overlie said gaps between said head portion of said locking arm and said side walls of said recess, thereby blocking said gaps. A connector member according to claim 1, wherein in said locking position of said terminal retainer (3), said gap blocking portions (30,41) thereof are located in said gaps between said head portion of said locking arm and said side walls of said recess. A connector member according to claim 3, wherein said terminal retainer has a connection portion (42) having opposite ends respectively joining said pair of gap blocking portions (41), said connector portion (42) underlying said locking arm (7).

Inventors: KONOYA HISASHI, NAKAMURA HIDETO, KONOYA, HISASHI, NAKAMURA, HIDETO
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1997
Main classification: H01R13
IPC codes: H01R13