Electrical connector with terminal position assurance device

Abstract: [Object] To provide a connector which can be produced by a mold having a simple configuration. [Solution] In the inner surfaces of the opposite side walls of a cavity 11 of a connector housing 10 are formed guiding grooves 16 for permitting the passage of restricting projections 24 when a female terminal fining 20 is inserted while being properly oriented. In the outer surfaces of the opposite side walls of the connector housing 10 are formed guide grooves 18 for permitting the passage of engaging projections 42 of a retainer 40. Through holes 17 are so formed in the side walls of the connector housing 10 as to partially communicate the guiding grooves 16 and the guide grooves 18.

Description: The present invention relates to a connector provided with a terminal fitting having a restricting projection for preventing the upside-down insertion of a terminal fitting. A known connector of this type is disclosed in Japanese Unexamined Patent Publication No. 5-47433. This connector is constructed such that a restricting projection is formed on one side surface of a female terminal fitting, and a guiding groove for permitting the passage of this restricting projection is formed in the inner wall of a cavity of a connector housing. When the terminal fitting is inserted while being properly oriented, the restricting projection can pass along the guide groove to be insertable into the cavity. When the terminal fitting is inserted upside-down, the restricting projection cannot be inserted into the cavity by being unable to enter the guiding groove. On the other hand, this type of connector is generally provided with a resin locking portion for locking the terminal fitting into the cavity and a retainer for preventing the deformation of the resin locking portion in an unlocking direction. The retainer is mountable on the connector housing by engaging an elastic engaging claw integrally formed therewith with an engaging hole formed in the connector housing. However, in the aforementioned connector, it is necessary to independently form the guide groove in the connector housing and the engaging hole used to mount the retainer. This complicates the construction of a mold, especially of a pin portion for forming the cavity, causing an increased cost for the mold, and reduces the rigidity of the pin, making it likely to be broken. In view of the above problems, an object of the present invention is to provide a connector which can be produced by a mold having a simplified construction. This object is solved according to the invention by a connector according to claim 1. preferred embodiments are subject of the dependent claims. According to the invention, there is provided a connector in which at least one terminal fitting is inserted or insertable into a cavity formed in a connector housing, a retainer for retaining the terminal fitting substantially in the cavity is at least partially mounted on the connector housing in the longitudinal direction to an insertion direction of the at least one terminal fitting, wherein the terminal fitting is provided with at least one restricting projection for preventing the terminal fitting from being inserted up-side-down or in a wrong orientation, and an inner wall surface of the cavity of the connector housing is formed with at least one guiding groove or a corresponding number of guide grooves for permitting the passage of the restricting projection(s) when the terminal fitting is inserted while being properly oriented, wherein at least one through hole penetrating an outer wall of the connector housing is so formed as to be substantially continuous with the guiding groove, and the retainer is made mountable on the connector housing by engaging at least one engaging projection formed in or on the retainer with the through hole. Accordingly, since the through hole used to mount the retainer can be formed, taking advantage of the guiding groove for preventing the upside-down insertion of the terminal fitting, a mold is advantageously allowed to have a simple construction. According to a preferred embodiment of the invention, the through hole is so formed as to be substantially continuous with the back or rear portion of the guiding groove as seen in an insertion direction of the terminal fitting. According to a preferred embodiment, there is provided a connector in which a terminal fitting is inserted into a cavity formed in a connector housing, a resin or elastic locking portion formed in the connector housing locks the terminal fitting to prevent the terminal fitting from coming out of the cavity, a retainer for restricting a deformation of the resin or elastic locking portion in an unlocking direction is mounted on the connector housing, the terminal fitting is provided with a restricting projection for preventing the terminal fitting from being inserted upside-down, and an inner wall surface of the cavity of the connector housing is formed with a guiding groove for permitting the passage of the restricting projection when the terminal fitting is inserted while being properly oriented, wherein a through hole penetrating an outer wall of the connector housing is so formed as to be continuous with the back of the guiding groove, and the retainer is made mountable on the connector housing by engaging an engaging projection formed in the retainer with the through hole. Preferably, a guide groove for guiding the engaging projection of the retainer toward the through hole is formed in the outer wall of the connector housing, and the through hole is so formed as to communicate the rear end of the guide groove and the rear end of the guiding groove. Accordingly, the through hole can be formed, taking advantage of a mold pin for forming the guide groove and the guiding groove. This obviates the need for a slide construction, enabling the mold to be further simplified. Further preferably, at least one resin or elastic locking portion formed in the connector housing locks or can lock the terminal fitting to prevent the terminal fitting from coming out of the cavity. Thus the terminal fitting can be securely locked in the cavity. Still further preferably, the connector housing is formed with a deformation permitting space for permitting the elastic locking portion to be deflected or deformed upon insertion and withdrawal of the terminal fitting into or from the cavity. Further preferably, the retainer comprises at least one deformation restricting portion for restricting a deformation of the resin or elastic locking portion in an unlocking direction thus retaining the terminal fitting substantially in the cavity. Thus the terminal fitting can be securely prevented by the retainer from coming out of the cavity. Most preferably, the deformation restricting portion is located in the deformation permitting space when the retainer is at least partially mounted on the connector housing. According to a further preferred embodiment, the at least one restricting projection is formed on a substantially box-shaped portion of the terminal fitting. These and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawings in which: FIG. 1 is an exploded vertical section of a connector according to a first embodiment of the invention, FIG. 2 is an exploded horizontal section of the connector, FIG. 3 is a horizontal section of the assembled connector, FIG. 4 is an exploded vertical section of a connector according to a second embodiment of the invention, and FIG. 5 is a vertical section of the assembled connector of FIG. 4. < First Embodiment> Hereafter, a first embodiment of the invention is described with reference to FIGS. 1 to 3. Identified by 10 in these Figures is a connector housing which is formed with a cavity 11 for substantially accommodating a female terminal fitting 20. The cavity 11 substantially extends along forward and backward directions (transverse direction of FIG. 1). A tab insertion opening 12 communicating the cavity 11 is open in the mating or front surface of the connector housing 10. If a tab portion of an unillustrated male terminal fitting is inserted or insertable through the tab insertion opening 12 with the female terminal fitting 20 accommodated in the cavity 11, this is connected with the female terminal fitting 20. In the cavity 11, an elastic or resin locking portion 13 (or deformable or deflectable locking portion) is integrally or unitarily formed with the connector housing 10. The elastic locking portion 13 is so formed that its free end projects forward of the connector housing 10 and has a locking projection 14 on the upper surface of its leading end. Below or in a deflection direction of the elastic locking portion 13 is provided a deformation permitting space 15 for permitting the leading end of the elastic locking portion 13 to be deformed downward. The female terminal fitting 20 is of a known shape which is comprised of an insulation barrel 21 to be fastened to an insulation coating of the wire 30 together with a rubber seal 32 for protecting the wire 30 from water, a wire barrel 22 to be fastened to a core 31 of the wire 30 and a substantially box-shaped portion 23 before or adjacent or neighbouring to the barrels 21, 22. An elastic contact piece (not shown) to be connected with the unillustrated male terminal fitting is provided in the box-shaped portion 23. Restricting projections 24 are formed on the outer surfaces of the preferably opposite side walls of the box-shaped portion 23. The restricting projections 24 are substantially continuous with the box-shaped portion 23 before and after them along the insertion direction of the female terminal fitting 20, and cut off from the box-shaped portion 23 at the top and bottom and bulge out preferably in U-shape therefrom. The restricting projections 24 are formed in positions displaced from the vertical center of the female terminal fitting 20, so that the positions thereof along vertical direction are different if the female terminal 20 is held upside-down. On the other hand, guiding grooves 16 for permitting the passage of the restricting projections 24 when the female terminal fitting 20 is inserted while being properly oriented are so formed in the inner surface of the opposite side walls of the cavity 11 of the connector housing 10 as to substantially extend along the insertion direction of the female terminal fitting 20. At the back of the guiding grooves 16 are formed through holes 17 substantially penetrating the side walls of the connector housing 10. The through holes 17 are so formed as to communicate preferably with the halves of corresponding guide grooves 18 which extend backward from the leading end of the cavity 11 to an intermediate position, and the front parts of the guiding grooves 16 of the restricting projections 24 (see FIG. 2). The through holes 17 are formed by providing projections for forming the guide grooves 18 in a specified portion of a mold for forming the outer wall of the connector housing 10 and projections for forming the guiding grooves 16 in a specified portion of the mold for forming the cavity 11, such that the leading ends of these projections are to be brought into contact to overlap when the molds are clamped. A retainer 40 is mountable on a front part of the connector housing 10. The retainer 40 has such a substantially rectangular tubular shape as to substantially cover the front part of the connector housing 10 in its mount position. In a position of the retainer 40 substantially corresponding to the tab insertion opening 12 of the connector housing 10 is similarly formed a tab insertion opening 41 for permitting the insertion of the tab portion of the male terminal fitting. On the inner surfaces of the opposite side walls of the retainer 40 are formed engaging projections 42 engageable with the through holes 17 by being inserted along the guide grooves 18 of the connector housing 10. The retainer 40 is formed with a deformation restricting portion 43 which is located in the deformation permitting space 15 or in a deflection direction of or preferably below the elastic locking portion 13 of the connector housing 10 when the retainer 40 is properly mounted. The deformation restricting portion 43 is located below the elastic locking portion 13 when the connector housing 10, the female terminal fitting 20 and the retainer 40 are properly assembled with each other, thereby restricting the deformation of the elastic locking portion 13. This embodiment is constructed as described above, and is assembled in the following procedure. When the female terminal fitting 20 is inserted into the cavity 11 preferably from behind the connector housing 10 while being properly oriented, the leading end of the box-shaped portion 23 is brought or bringable into contact with the locking projection 14 of the elastic locking portion 13, thereby deforming the elastic locking portion 13 toward the deformation permitting space 15, and the female terminal fitting 20 is inserted or insertable in an insertion direction or toward the back of the cavity 11. At this time, the guiding grooves 16 of the connector housing 10 permit the passage of the restricting projections 24 formed on the box-shaped portion 23. When the female terminal fitting 20 is inserted substantially to its proper position, the elastic locking portion 13 returns to its original position due to its elastic restoring force to be engaged with the bottom rear end of the box-shaped portion 23, with the result that the female terminal fitting 20 is locked in the cavity 11. If the female terminal fitting 20 is inserted upside-down into the cavity 11, an operator can notice an error since the restricting projections 24 cannot enter the guiding grooves 16. On the other hand, when the retainer 40 is mounted on the front part of the connector housing 10, the engaging projections 42 of the retainer 40 are slightly elastically deformed outward to pass along the guide grooves 18 of the connector housing 10. When the retainer 40 substantially reaches its proper mount position, the engaging projections 42 fall into the through holes 17 due to their elastic restoring forces to prevent the disengagement of the retainer 40 from the connector housing 10. In this way, the assembling is completed (see FIG. 3). This embodiment has an advantage that the mold has a simple configuration since the locking mechanism for the retainer 40, i.e. the through holes 17 can be formed, taking advantage of the guiding grooves 16 formed to prevent the female terminal fitting 20 from being inserted upside-down according to this embodiment. < Second Embodiment> FIGS. 4 and 5 show a second embodiment. Unlike the restricting projections 24 of the female terminal fitting 20 in the first embodiment, a restricting projection is formed on the outer surface of the upper wall of the box-shaped portion 63. In the following, no description is given on the same or similar elements as those of the first embodiment. A restricting projection 64 formed on the outer surface of the upper wall of a substantially box-shaped portion 63 of a female terminal fitting 60 as shown in FIG. 4 is substantially continuous with the box-shaped portion 63 adjacent or at its front and rear ends with respect to the insertion direction of the female terminal fitting 60, and bulges out preferably in U-shape by being cut off at its left and right sides. On the other hand, a guiding groove 56 for permitting the passage of the restricting projection 64 when the female terminal fitting 60 is inserted while being properly oriented is formed in the inner surface of the ceiling wall of a cavity 51 of a connector housing 50. Further, a through hole 57 is formed at one end or at the back of the guide groove 56. A retainer 70 preferably having a substantially rectangular tubular shape is mountable on a front part of the connector housing 50. An engaging projection 71 engageable with the through hole 57 of the connector housing 50 is formed on the inner surface of the ceiling wall of the retainer 70. During the assembling of the connector according to this embodiment, the restricting projection 64 formed on the box-shaped portion 63 is permitted to enter the cavity 51 by the guiding groove 56 of the connector housing 50. Thus, if the female terminal fitting 60 is mistakenly inserted upside-down into the cavity 51, the female terminal fitting 60 cannot be inserted to its proper mount position because of the restricting projection 64 standing in the way. Further, when the retainer 70 is mounted on the front part of the connector housing 50, the engaging projection 71 of the retainer 70 moves while being slightly elastically deformed upward. When the retainer 70 reaches its proper mount position, the engaging projection 71 falls into the through hole 57 due to its elastic restoring force (see FIG. 5). In this embodiment as well, the mold having a simple configuration can be used since the locking mechanism for the retainer 70, i.e. the through holes 57 can be formed, taking advantage of the guiding groove 56 formed to prevent the female terminal fitting 60 from being inserted upside-down. The present invention is not limited to the described and illustrated embodiment, but a variety of changes can be made without departing from the scope of the invention as defined in the claims.

Claims: A connector in which at least one terminal fitting (20; 60) is inserted or insertable into at least one cavity (11; 51) formed in a connector housing (10; 50), a retainer (40; 70) for retaining the terminal fitting (20; 60) substantially in the cavity (11; 51) is at least partially mounted on the connector housing (10; 50) in the longitudinal direction to an insertion direction of the at least one terminal fitting (20; 60), wherein the terminal fitting (20; 60) is provided with at least one restricting projection (24; 64) for preventing the terminal fitting (20; 60) from being inserted up-side-down, and an inner surface of the wall of the cavity (11; 51) is formed with at least one guiding groove (16; 56) for permitting the passage of the restricting projection(s) (24; 64) when the terminal fitting (20; 60) is inserted while being properly oriented, wherein at least one through hole (17; 57) penetrating the outer wall of the cavity (11; 51) is so formed as to be substantially continuous with the guiding groove (16; 56), and the retainer (40; 70) is made mountable on the connector housing (10; 50) by engaging at least one engaging projection (42; 71) formed in or on the retainer (40; 70) with the through hole (17; 57). A connector according to claim 1, wherein the through hole (17; 57) is so formed as to be substantially continuous with the rear portion of the guiding groove (16; 56) as seen in an insertion direction of the terminal fitting (20; 60). A connector according to one or more of the preceding claims, wherein at least one guide groove (18) for guiding the engaging projection (42; 71) of the retainer (40; 70) toward the through hole (17; 57) is formed in the outer surface of the cavity (11; 51), and wherein the through hole (17; 57) is so formed as to communicate the rear end of the guide groove (18) and the rear end of the guiding groove (16; 56). A connector according to one or more of the preceding claims, wherein at least one elastic locking portion (13) formed in the cavity (11; 51) locks or can lock the terminal fitting (20; 60) to prevent the terminal fitting (20; 60) from coming out of the cavity (11; 51). A connector according to claim 4, wherein the cavity (11; 51) is formed with a deformation permitting space (15) formed such that the elastic locking portion (13) can be deflected upon insertion and withdrawal of the terminal fitting (20; 60) into or from the cavity (11; 51). A connector according to one or more of the preceding claims, wherein the retainer (40; 70) comprises at least one deformation restricting portion (43) for restricting a deformation of the elastic locking portion (13) in an unlocking direction thus retaining the terminal fitting (20; 60) substantially in the cavity (11; 51). A connector according to claims 6 and 5, wherein the deformation restricting portion (43) is located in the deformation permitting space (15) when the retainer (40) is at least partially mounted on the connector housing (10). A connector according to one or more of the preceding claims, wherein the at least one restricting projection (24; 64) is formed on a substantially box-shaped portion (23; 63) of the terminal fitting (20; 60). A connector according to one or more of the preceding claims and claim 3 having two or more cavities (11; 51) into which a corresponding number of terminal fittings (20; 60) is inserted or insertable, wherein a preselected number equal to or lower than the total number of cavities (11; 51) is provided with a guide groove 818) and a corresponding through hole (17; 57).

Inventors: TANAKA NOBUYOSHI, TANAKA, NOBUYOSHI
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1999
Main classification: H01R13
IPC codes: H01R13