Connector

Abstract: [Object] To prevent a locking portion from being excessively deformed when the insufficient insertion of a terminal fitting is detected. [Solution] Cavities 3 are provided in two stages, and locking portions 11 thereof are arranged back to back to share deformation permitting spaces 16. The upper and lower locking portions 11 are arranged such that the longitudinal axes thereof are transversely offset to each other. Detecting portions 23 to be inserted into the deformation permitting spaces 16 project from a retainer 20. At the left and right ends of an inserting end surface 24 of each detecting portion 23, excessive deformation preventing portions 25 which can individually come into contact with leading ends 13 of the upper and lower locking portions 11 are symmetrically formed with respect to vertical direction. If a female terminal fitting 8 is insufficiently inserted as in the upper stage of FIG. 7, the retainer 20 may further deform the locking portion 11 after coming into contact therewith, while being inserted. However, the excessive elastic deformation of the locking portion 11 is restricted by the leading end 13 thereof being brought into contact with the excessive deformation preventing portion 25 at the lower side.

Description: The present invention relates to a connector provided with a retainer. As a connector provided with a front type retainer, the one disclosed in Japanese Utility Model Publication No. 63-37085 is known. This connector is, as shown in FIG. 10, constructed such that cavities b are provided in two stages in a housing and locking portions c are formed back to back in the respective cavities b. Terminal fittings d are inserted into the cavities b from behind, and are pushed in while deforming the locking portions c into a common deformation permitting space e as shown in the upper stage of FIG. 10. When the terminal fittings d are inserted to their proper insertion positions, they are locked so as not to come out of the cavities b by the locking portions c which have been restored to their original shape to be fitted into locking holes f. There is also provided a retainer g to be inserted into the deformation permitting space e from front. If the terminal fittings d are properly inserted, the retainer g is inserted into the deformation permitting space e to prevent the elastic deformation of the locking portions c, thereby doubly locking the terminal fittings d. On the other hand, if the terminal fitting d is left insufficiently inserted as shown in the upper stage, any further insertion of the retainer g is prevented due to the contact with the locking portion c projecting into the deformation permitting space e. In this way, the insufficient insertion of the terminal fitting d can be detected. In the prior art construction, it does not cause any problem if the retainer g is slowly inserted in the case that the locking portion c of the terminal fitting d left insufficiently inserted projects into the deformation permitting space e. If the retainer g is forcibly pushed, it may be inserted by deforming the locking portion c to a large extent after coming into contact with the leading end thereof. Then, the locking portion c may be damaged or broken at its base portion or the like and the insertion of the retainer g makes it unable to detect the insufficient insertion of the terminal fitting d. Document EP-A1-0 420 010 discloses an electrical connector according to the preamble of claim 1, matable with a pin header, wherein the connector comprises a retainer to lock terminal fittings into the connector. The retainer further comprises a secondary lock which is able to indicate a state of incomplete insertion of a terminal fitting and prevents the locking device from damage in such a state. Document EP-A1-0 827 236 discloses an electrical connector comprising a retainer to lock terminal fittings into the connector, wherein there are provided excessive deformation preventing portions on both, the retainer and the connector to prevent the locking portion from damage in a state of incomplete insertion of a terminal fitting into the connector. It is the object of the invention to provide a connector with enhanced protection of damage of a locking portion, while detecting insufficient insertion of the a terminal fitting and keeping the connector simple. This object is fulfilled by the connector having the features disclosed in claim 1. Preferred embodiments are defined in the dependent subclaims. Advantageously, the connector according to the invention can further be manufactured in decreased size. According to the invention, a damage of the locking portion can be prevented by preventing an excessive elastic and/or non elastic deformation thereof. When the locking portion is elastically deformed to project into the deformation permitting space, the retainer comes into contact with the locking portion while being inserted into the deformation permitting space. If the retainer is particularly strongly inserted, it may further elastically deform the locking portion. However, the deformable end of the locking portion is brought into contact with the excessive deformation preventing portion provided on the retainer, thereby preventing the locking portion from being excessively elastically deformed. The above prevents the locking portion from being damaged and/or broken, and the insufficient insertion of the terminal fitting can be accurately detected. Furthermore, according to the invention, the locking portions of the plurality of cavities are arranged substantially back to back so that a pair of the corresponding locking portions can be elastically deformed to project into the at least partly common deformation permitting space, and/or wherein the longitudinal axes of the pair of the locking portions are transversally offset to each other, and the retainer is provided with the excessive deformation preventing portions in positions corresponding to the respective locking portions. The excessive deformation of the locking portion during the insufficient insertion detection can be prevented even in connectors of the type in which deformation permitting spaces are shared by two locking portions by arranging locking portions back to back in order to make the connector smaller. Preferably, one or more wall forming portions are formed on the retainer, each of which forms a cavity wall, preferably a bottom or ceiling wall of the respective cavity, in front of the corresponding locking portion when the retainer is inserted to its proper insertion position. According to a further preferred embodiment, the substantially middle of an inserting end of each detecting portion with respect to a widthwise direction thereof is retracted from opposing ends to form a recess. Preferably, the recess is formed such that the inserting end surface substantially has a triangular cross section. 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 a vertical section of a connector before female terminal fittings and a retainer are mounted, FIG. 2 is a plan view in section of a female housing, FIG. 3 is a front view of the female housing, FIG. 4 is a rear view of the retainer, FIG. 5 is a plan view of the retainer, FIG. 6 is a perspective view of the retainer when viewed from front, FIG. 7 is a vertical section showing an operation of inserting the female terminal fittings, FIG. 8 is a vertical section showing a state where the retainer is in its proper insertion position, FIG. 9 is a partial enlarged vertical section showing a state where the insufficient insertion of the female terminal fitting is detected, and FIG. 10 is a vertical section of a prior art connector. Hereinafter, one embodiment of the invention is described with reference to FIGS. 1 to 9. In this shown embodiment, the invention is applied to a female connector of the type which makes a connection detection using a spring. In FIGS. 1 to 3, a female connector housing (hereinafter, "female housing") identified by 1 is made e.g. of a synthetic resin material. The female housing 1 has a main body 2 which is formed with e.g. eight cavities 3: preferably four in an upper stage and four in a lower stage. An outer tubular portion 4 having an open front end is formed substantially around a front half of the main body 2. Into the outer tubular portion 4 is fitted an unillustrated mating male connector housing. On the lateral, preferably upper surface of the main body 2 are provided a lock arm 5 for holding the male and female housings connected, a spring holder 6 assembled with a coil spring for detecting the connected state of the housings, etc. These members are described in detail later. Four cavities 3 are arranged substantially side by side in each of the upper and lower stages as described above. In the mating side, preferably the front surface of each cavity 3 is formed a terminal insertion opening 10 through which a tab of a corresponding male terminal mounted in the mating male housing is insertable. In the bottom walls of the upper cavities 3 and the ceiling walls of the lower cavities 3 are formed locking portions 11. These locking portions 11 have a known construction of extending forward with the leading ends thereof hanging free and being provided with locking projections 12 fittable into locking holes 9 formed in female terminal fittings 8. Although the upper and lower locking portions 11 are provided back to back, the upper locking portions 11 are located toward the right ends of the bottom walls of the corresponding cavities 3 and the lower locking portions 11 are located toward the left ends of the ceiling walls of the corresponding cavities 3 when viewed from front. In other words, the longitudinal axes of the corresponding locking portions in the upper and lower stages are transversely offset or displaced. An insertion space 14 extends substantially over the entire width of the female housing 1 between the upper and lower stages of the cavities 3 in the front part of the main body 2. A back side of the insertion space 14 is partitioned by partition plates 15, so that e.g. four deformation permitting spaces 16 are defined between the pairs of the corresponding upper and lower locking portions 11. The leading sides or portions of the upper and lower locking portions 11 are elastically deformable into the corresponding deformation permitting spaces 16. In other words, the upper and lower locking portions 11 at least partially share the respective deformation permitting spaces 16. A retainer 20 for doubly locking the female terminal fittings 8 and detecting the insufficient insertion of the female terminal fittings 8 is mountable preferably at the front surface of the main body 2. This retainer 20 is preferably of so-called front type and is preferably in the form of a cap to be fitted on the front end of the main body 2 as shown in FIGS. 4 to 6. In the rear surface (left surface in FIG. 1) of the retainer 20 with respect to an insertion direction, a total of e.g. eight windows are formed to have a lattice-like shape as a whole and substantially correspond to the respective cavities 3. A base plate 22 to be inserted into the above insertion space 14 is provided in the substantially middle of the retainer 20 with respect to vertical or height direction. Four detecting portions 23, at least a part of which is substantially closely insertable into the corresponding deformation permitting spaces 16, project from the leading end of the base plate 22. The substantially middle of an inserting end surface 24 of each detecting portion 23 with respect to the thickness or width direction thereof is retracted from the opposite ends, so that the inserting end surface 24 has a triangular cross section. At the left and right ends of the inserting end surface 24 of each detecting portion 23, excessive deformation preventing portions 25 for restricting the elastic deformation of the corresponding locking portions 11 by coming into contact with leading ends 13 of the locking portions 11 are formed substantially symmetrically with respect to vertical direction. More specifically, the excessive deformation preventing portions 25 are formed on lower slanted surfaces at the left ends of the inserting end surfaces 24 of the detecting portions 23 when viewed from front (front side in FIG. 6) so as to come into contact with the leading ends 13 (FIG. 7) of the upper locking portions 11. On the other hand, the excessive deformation preventing portions 25 are formed on upper slanted surfaces at the right ends of the inserting end surfaces 24 of the detecting portions 23 when viewed from front so as to come into contact with the leading ends 13 of the lower locking portions 11. On the upper and lower surfaces of the base plate 22 of the retainer 20 are formed wall forming portions 27, each of which forms the bottom or ceiling wall in front of the corresponding locking portion 11 when the retainer 20 is inserted substantially to its proper insertion position. A pair of upper and lower elastic locking pieces 28 is formed on each of left and right side walls of the retainer 20. Further, as shown in FIG. 2, locking holes 29 into which the respective elastic locking pieces 28 are elastically fittable when the retainer 20 is inserted substantially to its proper insertion position are formed in the left and right side walls of the main body 2 of the female housing 1. When the female terminal fitting 8 is inserted into the corresponding cavity 3 preferably from behind, it is pushed while elastically deforming the locking portion 11 to project into the deformation permitting space 16 shared by the pair of corresponding upper and lower locking portions 11 as shown in the upper stage of FIG. 7. When the female terminal fitting 8 is inserted to its proper insertion position, the locking portion 11 is restored preferably substantially to its original shape and at least partially fitted into the locking hole 9 as shown in the lower stage of FIG. 7. In this way, the female terminal fitting 8 is locked so as not to be withdrawn in a withdrawal direction, preferably the backward direction. When the insertion of all female terminal fittings 8 is completed, the retainer 20 is inserted so as to be put on the front part of the main body 2 of the female housing 1. When the retainer 20 is inserted to a specified position, the retainer 20 is so mounted as not to disengage by the engagement of the elastic locking pieces 28 and the locking holes 29 of the main body 2. At substantially this time, at least a part of the respective detecting portions 23 are substantially closely inserted into the corresponding deformation permitting spaces 16 as shown in FIG. 8. Since the elastic deformation of the locking portions 11 is restricted in this way, the female terminal fittings 8 are doubly locked. On the other hand, the female terminal fitting 8 may be left insufficiently inserted without being inserted to its proper insertion position as shown in the upper stage of FIG. 7. In such a case, the locking portion 11 is elastically deformed and the leading end 13 thereof is projecting into the deformation permitting space 16. If the retainer 20 is inserted in this state, the inserting end surface 24 of the corresponding detecting portion 23 comes into contact with the projecting locking portion 11 as shown in FIG. 9. Here, if the retainer 20 is forcibly inserted, it may be further inserted while further deflecting the locking portion 11. However, even if the locking portion 11 tries to be deflected, the leading end 13 thereof is brought into contact with the excessive deformation preventing portion 25 (lower side) provided on the inserting end surface 24 of the detecting portion 23 (FIG. 9). This prevents the locking portion 11 from being excessively deformed and stops any further insertion of the retainer 20. Also in the case that the female terminal fitting 8 is left insufficiently inserted in the lower stage, the corresponding locking portion 11 is brought into contact with the upper side excessive deformation preventing portion 25 in a similar manner, which prevents it from being excessively elastically deformed. If the presence of the female terminal fitting 8 left insufficiently inserted is detected by the retainer 20 being unable to be inserted to its proper insertion position as described above, the corresponding female terminal fitting 8 may be further pushed to its proper insertion position. As described above, the excessive elastic deformation of the locking portions 11 is restricted by the excessive deformation preventing portions 25 provided on the retainer 20 according to this embodiment. This prevents the locking portions 11 from being damaged or broken. Further, since the excessive deformation preventing portions 25 can also restrict any further insertion of the retainer 20, the insufficient insertion of the female terminal fittings 8 can be more accurately detected. The female housing 1 according to this embodiment is designed to reduce its height by arranging the upper and lower locking portions 11 back to back to share the deformation permitting spaces 16. Here, if the pairs of upper and lower locking portions 11 are formed in the middle of the cavities 3 with respect to the widthwise direction thereof, i.e. the longitudinal axes of the upper and lower locking portions are substantially aligned with respect to the transverse direction, the excessive deformation preventing portions 25 as above cannot be formed on the detecting portions 23 of the retainer 20. Since the corresponding upper and lower locking portions 11 are arranged such that the longitudinal axes thereof are transversely offset to each other in this embodiment, the excessive deformation preventing portions 25 which can interact with the upper and lower locking portions 11 can be formed at the left and right ends of the detecting portions 23. < Other Embodiments > The present invention is not limited to the described and illustrated embodiment but, for example, the following embodiments are also embraced by the technical scope of the present invention as defined in the claims. Besides the following embodiments, a variety of other changes can be made without departing from the scope as defined in the claims. (2) The invention is not only applicable to female housings as shown in the foregoing embodiment, but also similarly applicable to male housings. LIST OF REFERENCE NUMERALS 1 Female Housing 3 Cavity 8 Female Terminal Fitting 9 Locking Hole 11 Locking Portion 13 Leading End (Deformable End) 16 Deformation Permitting Space 20 Retainer 23 Detecting Portion 24 Inserting End Surface 25 Excessive Deformation Preventing Portion

Claims: A connector, comprising: one or more cavities (3) into which one or more terminal fittings (8) are to be inserted and which cavities are provided with elastically deformable locking portions (11), each locking portion (11) permitting the insertion of the corresponding terminal fitting (8) while being elastically deformed to project into a deformation permitting space (16) and being restored to a position substantially not projecting into the deformation permitting space (16) when the terminal fitting (8) is inserted to its proper insertion position, thereby locking the terminal fitting (8), and a retainer (20) which has detecting portions (23), each of which is insertable into one of the deformation permitting spaces (16) and comes into contact with the locking portion (11) elastically deformed to project into the deformation permitting space (16) when the terminal fitting (8) is left insufficiently inserted, thereby enabling a detection of the insufficient insertion of the terminal fitting (8), wherein each detecting portion (23) comprises an excessive deformation preventing portion (25) for restricting an excessive elastic deformation of the locking portion (11) by coming into contact with a contact part (13) of the locking portion (11) when the retainer (20) comes into contact with the elastically deformed locking portion (11), due to an insufficient inserted terminal fitting, and wherein the locking portions (11) of the plurality of cavities (3) are arranged substantially back to back so that a pair of the corresponding locking portions (11) can be elastically deformed to project into the at least partly common deformation permitting space (16), characterized in that the longitudinal axes of the pair of the locking portions (11) are transversally offset to each other, and the retainer (20) is provided with the excessive deformation preventing portions (25) in positions corresponding to the respective locking portions (11). A connector according to one or more of the preceding claims, wherein each locking portion (11) is restored substantially to its original shape when the terminal fitting (8) is inserted to its proper insertion position, thereby locking the terminal fitting (8). A connector according to one or more of the preceding claims, wherein one or more wall forming portions (27) are formed on the retainer (20), each of which forms a cavity wall in front of the corresponding locking portion (11) when the retainer (20) is inserted to its proper insertion position. A connector according to one or more of the preceding claims, wherein the substantially middle of an inserting end (24) of each detecting portion (23) with respect to a widthwise direction thereof is retracted from opposing ends to form a recess. A connector according to claim 4, wherein the recess is formed such that the inserting end surface (24) substantially has a triangular cross section.

Inventors: ISHIKAWA RYOTARO, KAWASE HAJIME, NISHIDE SATORU, ISHIKAWA, RYOTARO, KAWASE, HAJIME, NISHIDE, SATORU
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1999
Main classification: H01R13
IPC codes: H01R13