Patent Publication Number: US-4921448-A

Title: Connector terminal retainer construction

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a wire harness connector, and more particularly to a terminal retainer construction for fixedly anchoring in position the terminal members which are inserted into terminal compartments in a wire harness connector housing. 
     2. Prior Art 
     For fixing in position the terminal members which are inserted into terminal compartments in a connector housing, it has been the general practice to provide flexible or resilient retainer arms integrally on the inner wall surfaces of each terminal compartment, which retainer arms engage the terminal members upon insertion of the terminal members into the terminal compartments to prevent dislocation or dislodgement of the terminal members. Recently, a proposal has been made to provide a terminal retainer which is fittingly interlockable with a rear portion of the connector housing to prevent dislocation or dislodgement of the terminal members securely in cooperation with or in place of the flexible retainer arms. 
     FIG. 9 illustrates such a prior art retainer structure, which is provided with support projections d on the inner surfaces of opposing wall portions c of each terminal compartment b in a connector housing a. Tapered drive surface e are formed on the rear side of the support projections d, while temporary or provisional locking projections f and main locking projections g are provided in relatively rearward and forward positions on the outer wall surfaces with respect to the position of the housing a. 
     Indicated at h is a frame-like terminal retainer with resilient locking arms j and resilient retainer arms k extending forwardly from a frame body i respectively onto and into a connector housing a to be connected therewith. 
     The terminal retainer h is firstly joined with the housing a in a provisionally interlocked state where the resilient locking arms j are in interlocking engagement with the provisional locking projections f. In this state, the resilient retainer arms k are extended linearly forward without interfering with a terminal member l inserted into the terminal compartment b. 
     Nextly, the terminal retainer h is pushed in further to bring the retainer into a finally interlocked state where the resilient locking arms j are in interlocking engagement with the main locking projections g. In this state, the fore ends k 1  of the resilient retainer arms k which are abutted against the tapered drive surfaces e are thereby bent inward to grip a terminal press-on wire portion m, and located behind support projections n and o of the terminal member l to prevent its dislocation in the rearward direction. 
     In the above-described prior art arrangement, the resilient retainer arms k of the terminal retainer h which stop the terminal member l are forcibly deformed against its resiliency and retained in the deformed state by the tapered drive surfaces e, and therefore they are apt to be fixed in the deformed state losing resiliency under influence of heat. Such a non-resilient deformation makes it difficult to extract the terminal member or to re-insert the retainer member due to the interference of the deformed retainer arms k with the terminal member. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing situations, the present invention has as its object the provision of a connector terminal retainer which can eliminate the drawbacks of the prior art construction as discussed above. More specifically, it is an object of the present invention to provide a connector terminal retainer, wherein the terminal retainer to be fitted on a connector housing is provided with resilient retainer arms which are in an interfering position relative to terminal members being inserted into the connector housing to assume a provisionally interlocked state but which, after permitting insertion of the terminal members by resilient deformation, restore an original form when pushed into a finally interlocked state anchoring the terminal members fixedly in position, thus eliminating the problem of the conventional resilient retainer arms which become unusable due to permanent deformation. 
     In accordance with the present invention, in order to achieve the above-mentioned objects, there is provided a connector terminal retainer of the type including a connector housing having a plural number of terminal compartments, terminal members to be inserted into the compartments, and a terminal retainer fittingly interlockable with a rear portion of the connector housing stepwise through two stages; a stage of provisional interlocking and a stage of final interlocking, characterized in that the terminal retainer comprises a frame-like body with openings for insertion of the terminal members and resilient terminal-anchoring fingers extending forwardly into the terminal compartments, the resilient fingers being capable of restoring an original form by the resiliency thereof after insertion of the terminal members to anchor securely in the respective terminal compartments of the connector housing in the finally interlocked state of the terminal retainer free of the problem of permanent deformation. 
     The above and other objects, features and advantages of the invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings which show by way of example preferred embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings: 
     FIG. 1 is a perspective view of an embodiment of the invention, showing male and female connector housings which are provisionally interlocked with the respective terminal retainers; 
     FIG. 2 is a view similar to FIG. 1 but showing the connector housings and terminal retainers in finally interlocked state; 
     FIG. 3 is a view similar to FIG. 1 but showing the connector housings and terminal retainers in separated state; 
     FIG. 4 is a sectional view of the male and female housings and the terminal retainers in provisionally interlocked state; 
     FIG. 5 is a view similar to FIG. 4 but showing the two housings and terminal retainers in finally interlocked state; 
     FIG. 6 is a perspective view of another embodiment of the invention, showing the connector housings and terminal retainers in separated state; 
     FIG. 7 is a sectional view of the connector housings and terminal retainers of FIG. 6 in provisionally interlocked state; 
     FIG. 8 is a sectional view of the same connector housings and terminal retainers in finally interlocked state; 
     FIG. 9 is a sectional view of conventional connector housings and terminal retainers in provisionally interlocked state; and 
     FIG. 10 is a view similar to FIG. 9 but showing the connector housings and terminal retainers in finally interlocked state. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to FIG. 1 through 4, there is illustrated an embodiment of the invention, in which indicated at A is a male connector housing of a synthetic resin material, and at B is a female connector housing similarly of a synthetic resin material. Separately formed terminal retainers A 1  and B 1  are fitted on rear portions of the male and female connector housings A and B respectively. The connector housings A and B are provided with a plural number of terminal compartments 1 and 2 in two rows, namely, in upper and lower rows, receiving female type terminal members C in the terminal compartments of the male connector housing A and receiving male type terminal members D in the terminal compartments of the female connector housing B. 
     The terminal compartment 1 is provided with a stopper 3 at its front end and, integrally with its inner wall surface, with a resilient terminal holding finger 4, while the terminal compartment 2 is provided with a resilient terminal holding finger 5 integrally with its inner wall in addition to a stopper (not shown) located in an intermediate position. 
     Provided on the top side of the male connector housing A is a resilient locking arm 6 and provided with a locking projection 6a and an operating projection 6b. Opposingly to the resilient locking arm 6, the female connector housing B is provided with a locking portion 7 for engagement with the locking projection 6a. Further, the male and female connector housings A and B are provided with rearwardly extending resilient locking arms 8 and 9 at the opposite sides, respectively. 
     The terminal retainers A 1  and B 1  have frame-like main bodies 12 and 13 which internally define openings 10 and 11 to insert the terminal members C and D therethrough along with wires W connected to the respective terminal members, and which have forwardly extending resilient terminal anchoring fingers 14 and 15 opposingly to the corresponding terminal compartments 1 and 2 in the upper and lower compartment rows of the male and female connector housings A and B. The main bodies 12 and 13 of the terminal retainers A 1  and B 1  are provided with provisional locking projections 8a and 9a and main locking projections 8b and 9b at the opposite sides which are successively engageable with the resilient locking arms 8 and 9 of the male and female connector housings A and B, respectively. 
     Prior to insertion of the terminal members C and D, the connector housings A and B and the terminal retainers A 1  and B 1  are assembled into a provisionally interlocked state, with the resilient locking arms 8 and 9 in interlocking engagement with the provisional locking projections 8a and 9a as shown particularly in FIG. 1. In this state, the terminal members C and D are inserted into the terminal compartments 1 and 2 through the openings in the terminal retainers A 1  and B 1 . At this time, the inserted terminal members C and D cause the resilient terminal anchoring fingers 14 and 15, which are in an interfering position, to flex outward by flexural deformation against the resilient force of the resilient fingers 14 and 15. In the male connector housing A, the female type terminal members C are held in abutting engagement with stepped locking portions 14a  of the resilient fingers 14 as soon as electric contact portions of the terminal members C ride over the resilient fingers 14. On the other hand, in the female connector housing B, the male type terminal members D are held in abutting engagement with stepped locking portions 15a of the resilient fingers 15 as soon as locking projections 17, which are formed by slitting intermediate portions of the male type terminal members D, ride over the resilient terminal anchoring fingers 15 (FIG. 4). 
     Nextly, the terminal retainers A 1  and B 1  are pushed into the connector housings A and B until the resilient locking arms 8 and 9 engage with the main locking projections 8b and 9b to hold the retainers in a finally interlocked state (FIG. 2). By so doing, the resilient fingers 14 and 15 in engagement with the terminal members C and D push the latter into the respective terminal compartments 1 and 2 to engage the resilient terminal holding fingers 4 with the electric contact portions 16 in the connector housings A and engage the resilient terminal holding fingers 5 with locking holes 17 in the connector housing B(FIG. 5). The provisional locking projections 8a and 9a and main locking projections 8b and 9b are each provided with a tapered guide surface on the forwardly side, so that the resilient locking arms 8 and 9 can ride over these projections when the retainers are pushed in, through flexural deformation of the locking arms 8 and 9. 
     In the provisionally interlocked state, the terminal members C and D can be immediately engaged with the resilient terminal holding fingers 4 and 5 in the connector housings A and B by further pushing them into the respective terminal compartments. Even when the terminal member C and D are in an incompletely inserted state, they can be driven into engagement with the resilient terminal holding fingers 4 and 5 as the terminal retainers A 1  and B 1  are pushed into the finally interlocked state. 
     Referring to FIGS. 6 through 8, there is illustrated another embodiment of the invention, wherein resilient terminal holding fingers 4&#39; and 5&#39; in the upper and lower terminal compartments 1&#39; and 2&#39; of the male and female connector housings A&#39; and B&#39; are formed to extend upwardly and downwardly in a diverging fashion from a wall which partitions the upper and lower terminal compartments 1&#39; and 2&#39;, respectively. In the same manner as in the foregoing embodiments, these resilient terminal holding fingers 4&#39; and 5&#39; engage the female and male type terminal members C and D which are inserted symmetrically in face-to-face relation into the upper and lower terminal compartments 1&#39; and 2&#39;. 
     In this instance, the terminal retainers A 1  and B 1  are provided with a plural number of upwardly and downwardly diverging resilient terminal anchoring fingers 14&#39; and 15&#39; to engage the terminal members C and D in the same manner as in the first embodiment described above. 
     As described heretoabove, the connector terminal retainer construction of the present invention consists of a combination of a connector housing with a number of terminal compartments, terminal members to be inserted into the terminal compartments, and a terminal retainer to be fittingly interlocked with a rear portion of the connector housing through two stages; a stage of provisional interlocking and a stage of final interlocking. The terminal retainer is provided with openings for insertion of the terminal members and resilient terminal anchoring fingers extending into the terminal compartments in the connector housing, each one of the resilient fingers being capable of restoring its original form by its own resiliency in the finally interlocked position in engagement with a terminal member. Thus, the resilient terminal anchoring fingers retain resiliency while in engagement with the terminal members in the respective locking positions, without losing resiliency. It is followed by the fact that, even when the terminal members are inserted and extracted repeatedly, the resilient fingers can be easily displaced upon abutment thereon of a terminal member, facilitating insertion and extraction of the terminal members while holding them securely in fixed state in the interlocked position of the retainer.