Connector with secondary locking

Abstract: In installing a retainer (20) on a connector housing (10), a guide portion (21A) formed on a removal prevention portion (21) fits in the connector housing (10) before a holding piece (22) reaches the connector housing (10). In this manner, the retainer (20) is placed in position. Therefore, it does not occur that the front end of the holding piece strikes against the outer surface of the connector housing. Consequently, it is possible to prevent the holding piece (22) from striking against the connector housing (10) and thus prevent it from being deformed or damaged. In the state where the retainer (20) has been locked at the locking position, the guide portion (21A) penetrates through the connector housing (10) and substantially contacts the seal ring (13), thus preventing the removal of the seal ring (13). Thus, it is possible to reliably prevent the removal of the seal ring (13) by the guide portion (21A) without providing the connector housing (10) with a removal prevention component part separately from the guide portion (21A).

Description: The present invention relates to a connector in which removal of a terminal fitting is prevented by a retainer. As an example of a connector in which a retainer prevents removal of a terminal is disclosed in DE-A-3705739. In the connector, the terminal is inserted into a connector housing from the rear side thereof, the retainer is installed thereon from a side wall thereof, and the retainer is locked to the terminal to prevent the terminal from being dislocated rearward. A projection for preventing removal of the terminal is formed at a front end of an arm-shaped holding piece. The retainer is held at a predetermined position by mounting the holding piece on the connector housing along an outer surface thereof. In the retainer-mounted state, the projection for preventing removal of the terminal is locked to the terminal and prevents the removal of the terminal. In the above-described connector, the holding piece of the retainer is exposed to the outer surface of the connector housing. Thus, there is a possibility that component parts interfere with the holding piece. The removal prevention projection is formed at the front end of the holding piece. Therefore, the interference affects the removal prevention projection. In this case, there is a possibility that the removal prevention projection is dislocated in the direction in which it is removed from the terminal. Thus, the connector is not reliable in this respect. As means for solving the above-described problem, it is conceivable to form the removal prevention projection independently of the holding piece and fit the removal prevention projection into the connector housing. In this case, the removal prevention projection projects in the direction in which it is assembled on the connector housing, similarly to the holding piece. But such a configuration may cause the holding piece to be deformed or damaged when the front end thereof strikes against the outer surface of the connector housing. As means for preventing the deformation of the holding piece or the damage thereof, it is conceivable to increase its rigidity by making it thick or wide. In this case, the holding piece projects greatly from the outer surface of the connector housing, which does not comply with a demand for development of a compact connector. US-A-5167534 discloses a connector having a terminal lock plate inserted into an intermediate portion of a housing across terminal receiving holes, in which flexible lock arms for effecting primary locking of terminals have an increased retaining force. The connector includes a main housing, a sub-housing inserted into a frame portion provided at the front portion of the main housing, and a terminal lock plate, inserted into openings formed respectively through upper and lower walls of the frame portion. The terminal lock plate is of a frame-like construction having through holes arranged substantially in the same manner as the terminal rear half receiving holes and the terminal front half receiving holes so as to be aligned therewith when the lock plate is inserted into the main housing. Retaining portions, each adapted to engage a shoulder of an electrical contact portion of the male terminal, are formed respectively on the front edges of the upper and lower walls of each through hole and downwardly-directed flexible retaining arms are formed respectively on the opposite side faces of the terminal lock plate. GB-A-2255864 describes a connector comprising a housing defining a set of chambers receiving respective terminals and a retaining mechanism to retain the terminals releasably in a predetermined position in the chambers, the retaining mechanism comprising a retainer inserting aperture defined by the housing and communicating with the chambers and a retainer insertable into the retainer inserting aperture. A locking plate locks the retainer in a locked position in which the terminals are retained in the predetermined position. A further locking plate locks the retainer in a temporary position in which the terminals are removably insertable into the chambers. The present invention has been made in view of the above-described situation. It is an object of the present invention to provide a connector having an improved operability. This object is solved according to the invention by a connector according to claim 1 Preferred embodiments are subject of the dependent claims. Accordingly, there is provided a connector which allows to prevent a retainer from deforming when the retainer is installed on a connector housing. According to a preferred embodiment of the invention, there is provided a connector comprising a connector housing into which at least one terminal can be inserted, and a retainer which can be installed on the connector housing and prevent removal of the terminal, wherein the retainer has: a removal prevention portion which can be inserted into the connector housing and locked to the terminal; a holding piece which can be installed on the connector housing and hold the retainer at a predetermined installing position; and a guide portion formed at a front end of the removal prevention portion and projecting forward from an extended end of the holding piece in the direction in which the retainer is installed on the connector housing, whereby an inclination range of the terminal on the guide surface of the retainer is so set as to cover the movable range of the receiving surface based on the accumulative tolerance of the size tolerance of each of the connector housing, the retainer, the terminal, and the cavity. According to a preferred embodiment, the holding piece extends in the shape of a cantilever in a direction in which the retainer is installed on the connector housing. Preferably, the holding piece can be installed on the connector housing along an outer surface of a body thereof. Most preferably, the at least one terminal can be inserted from a rear side of the connector housing. According to a further preferred embodiment, there is provided a connector comprising a connector housing into which a terminal is inserted from a rear side thereof; and a retainer which is installed on the connector housing at a side surface thereof and prevents removal of the terminal. The retainer has a removal prevention portion inserted into the connector housing and locked to the terminal; a holding piece extending in the shape of a cantilever in a direction in which the retainer is installed on the connector housing and installed on the connector housing along an outer surface thereof and holding the retainer at a predetermined installing position; and a guide portion formed at a front end of the removal prevention portion and projecting forward from an extended end of the holding piece in the direction in which the retainer is installed on the connector housing. Preferably, the connector comprises a waterproof seal ring installed on a periphery of the connector housing, preferably of a body thereof. The retainer is installed on the connector housing such that a guide portion of the retainer penetrates through the connector housing, and the guide portion projects at a position of the periphery of the connector housing, preferably of the body thereof, such that the guide portion prevents removal of the seal ring. In installing the retainer on the connector housing, the guide portion formed at the front end of the removal prevention portion penetrates into the connector housing before the holding piece reaches the outer surface of the connector housing. In this manner, the removal prevention portion and the holding piece are placed in position. Therefore, it does not occur that the front end of the holding piece strikes against the outer surface of the connector housing. Consequently, it is possible to prevent the holding piece from being deformed or damaged The guide portion of the retainer has the function of preventing the removal of the seal ring. Thus, it is possible to use a small number of component parts than a connector requiring a removal prevention means separately from the guide portion. According to a preferred embodiment of the invention the removal prevention portion can be inserted into the connector housing and locked to the terminal by means of at least one locking portion; wherein the locking portion comprises a guide surface being arranged at an angle different from 0° or 180° with respect to an insertion/removal direction of the terminal for engaging a receiving surface of the terminal while the retainer is being moved to its locking position thereby pressing the terminal in its insertion direction. According to a preferred embodiment, the retainer is insertable into a retainer installing hole, and wherein the size relationship between the terminal and the cavity is so set that when the terminal reaches a predetermined primary locking position the receiving surface is located inside the retainer installing hole. Most preferably, the locking portion comprises a contact surface for engaging the terminal while the retainer is being moved to its locking position when the terminal is insufficiently inserted, in particular when the receiving surface thereof is located rearward from an inclination range the guide surface. 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 transverse sectional view showing a state in which a retainer is started to be installed on a connector housing in an embodiment of the present invention, Fig. 2 is a transverse sectional view showing a state in which the retainer is temporarily locked, Fig. 3 is a transverse sectional view showing a state in which the retainer is moved from a temporary locking position to a locking position, Fig. 4 is a transverse sectional view showing a state in which the retainer is locked, Fig. 5 is a front view showing the retainer, Fig. 6 is a vertical sectional view showing a state in which the retainer is temporarily locked, Fig. 7 is a transverse sectional view showing a state in which the retainer is locked, Fig. 8 is a partly enlarged vertical sectional view showing a state in which the retainer is temporarily locked, Fig. 9 is a partly enlarged vertical sectional view showing a state in which the retainer is locked, Fig. 10 is a partly enlarged horizontal sectional view showing a state in which a terminal is locked primarily, Fig. 11 is a partly enlarged horizontal sectional view showing a state in which the terminal is pressed to a position deeper than a first locking position, and Fig. 12 is a partly enlarged horizontal sectional view showing a state in which the terminal is inserted incompletely. An embodiment of the present invention will be described below with reference to Figs. 1 through 12. The connector of the embodiment is constructed of a connector housing 10 and a retainer 20. The connector housing 10 has a body 11 substantially long or elongated in the lengthwise direction thereof and a cylindrical hood portion 12 substantially open at its front portion and radially or laterally surrounding almost all of the front portion of the body 11 (FIGS. 6, 7). At the rear end of the hood part 12, a seal ring 13 is installed on the periphery of the body 11 preferably from the front side of the connector housing 10. The seal ring 13 waterproofs a fit-in portion between the connector housing 10 and a mating connector housing. The body 11 has a plurality of hollow cavities 14. A terminal 30 is at least partially inserted or insertable into each cavity 14 preferably from the rear side thereof. A lance 34 of the terminal 30 is locked to a receiving portion 14A of the cavity 14 to lock the terminal 30 primarily or in a first position. A slit-shaped retainer installing hole 15 is formed on the body 11. The retainer installing hole 15 substantially penetrates widthwise or at an angle different from 0° or 180°, preferably substantially normal with respect to the longitudinal direction of the body 11 through the body 11 from one outer side surface of the body 11 to the other side surface thereof. The opening portion of the retainer installing hole 15 on the outer surface of the body 11 is located along the front edge of the seal ring 13. On the upper and lower surfaces of the body 11, a guide groove 16 for guiding a holding piece 22 of the retainer 20 is formed along the front edge of the seal ring 13. A locking projection 17 for locking the retainer 20 to a temporary (or first) locking position and a (final or full or second) locking position is formed on the guide groove 16. On the hood part 12, a retainer insertion hole 18 is formed in correspondence to the opening of the retainer installing hole 15 at one side surface of the body 11. The retainer insertion hole 18 is preferably not slit-shaped unlike the retainer installing hole 15 but is rectangular and open widely in the lengthwise direction thereof. The retainer 20 is made e.g. of synthetic resin and has a removal prevention portion 21 and a pair of holding pieces 22. The removal prevention portion 21 is substantially thick and substantially rectangular and comparatively rigid. The removal prevention portion 21 is fitted or fittable in the retainer installing hole 15 tightly and removably. On the removal prevention portion 21, holes 23 allowing the terminal 30 to penetrate therethrough are formed in the substantially same arrangement as that of the cavity 14. A part of the edge of the hole 23 serves as a locking portion 24 which can be locked to a receiving surface 31 of the terminal 30 inserted or insertable into the cavity 14 normally (predetermined position). As shown in Fig. 6, in the state where the retainer 20 is temporarily locked to the connector housing 10, the hole 23 substantially matches the cavity 14 and allows the terminal 30 to be inserted into the cavity 14. As shown in Fig. 7, when the retainer 20 is locked at the locking position, the locking portion 24 of the hole 23 penetrates into the cavity 14 and is locked to the receiving surface 31 of the terminal 30. Thus, the terminal 30 is unremovably locked. As shown in Figs. 8 and 9, a projection portion 25 is formed on the locking portion 24. On the projection portion 25, there are formed a guide surface 26 inclining or arranged at an angle different from 0° or 180° with respect to the insertion/removal direction I/R of the terminal 30 and a contact surface 27 located in the rear of the guide surface 26 preferably in continuation therewith and substantially parallel with insertion/removal direction I/R of the terminal 30. The guide surface 26 retracts outside an insertion/removal path of the terminal 30 or spaced by a predetermined or predeterminable distance from the cavity 14 when the retainer 20 is locked at the temporary locking position, whereas the guide surface 26 engages an edge 32 of the receiving surface 31 (preferably when the terminal 30 is not fully inserted) while the retainer 20 is being moved to the locking position, thus pressing the terminal 30 in the insertion direction of the terminal 30. That is, the size relationship between the terminal 30 and the cavity 14 is so set that when the terminal 30 reaches a predetermined primary locking position at which the lance 34 of the terminal 30 is locked to the receiving portion 14A, the receiving surface 31 is located inside the retainer installing hole 15 (see Fig. 10). In thus setting the size relationship therebetween, the size tolerance of each of the connector housing 10, the retainer 20, the terminal 30, and the cavity 14 are considered. Regardless of whether the accumulative tolerance thereof is maximum at a plus side or a minus side, the receiving surface 31 is located inside the retainer installing hole 15. The inclination range S (see Fig. 8) of the terminal 30 on the guide surface 26 of the retainer 20 is so set as to cover the movable range of the receiving surface 31 based on the accumulative tolerance. Accordingly, regardless of whether the receiving surface 31 is located at the plus side or the minus side, the guide surface 26 surely contacts the edge 32 of the receiving surface 31. The holding piece 22 is substantially continuous with one peripheral edge of the removal prevention portion 21 through a substantially plate-shaped connection portion 28 extending along the outer side surface of the body 11. The holding piece 22 extends sideways in the shape of a cantilever or projection or overhang in correspondence to the upper and lower surfaces of the body 11. When a pair of the holding pieces 22 is installed on the connector housing 10, it is so located as to substantially sandwich the body 11 laterally or from above and below and so elastically expands that it is apart from the body 11. A temporary locking groove 29A and a main locking groove 29B which can be locked to the locking projection 17 of the body 11 are formed on a surface, of the holding piece 22, corresponding to the body 11. Referring to Figs. 5 and 7, the front end of the removal preventing portion 21 (which substantially extends in a direction of insertion of the retainer 20 into the housing body 11) projects substantially beyond the extending end portions of the holding pieces 22 in the insertion direction. Hence, the front end constitutes a fitting guide portion 21 A that serves to substantially fix or determine the position and/or orientation of the retainer 20 in the housing body 11. The guide portion 21A is preferably bevelled or slanted (FIG. 7) on preferably both edges (i.e. comprises one or two slanted portions being arranged at an angle different from 0°, 90° or 180° with respect to the insertion/removal direction I/R of the terminal 30). In assembling the retainer 20 on the connector housing 10, the retainer is approached to the side surface of the connector housing 10, with the front end of the removal prevention portion 21 and that of the holding piece 22 directed forward. At this time, the guide portion 21A is inserted into the retainer installing hole 15 before the front end of the holding piece 2 reaches the connector housing 10. The holding piece 22 has a such a length as to extend over the substantially entire upper and lower surfaces of the body 11 preferably in the widthwise direction thereof when the retainer 20 is locked. When the retainer 20 is locked, the holding piece 22 substantially contacts the front surface of the seal ring 13 and prevents the seal ring 13 from being removed, and the connection portion 28 extends along the outer side surface of the body 11 and substantially contacts the front surface of the seal ring 13, thus preventing the removal of the seal ring 13. At the side opposite to the connection portion 28, the guide portion 21 A located at the front end of the removal prevention portion 21 projects from the side surface of the body 11 and substantially contacts the front surface of the seal ring 13, thus preventing the retainer 20 from being removed. The operation of the embodiment is described below. In assembling the connector of the embodiment, initially, as shown in Fig. 2, the retainer 20 is temporarily locked to the connector housing 10. At this time, when the retainer 20 is approached to the connector housing 10, the guide portion 21 A is inserted into the retainer installing hole 15 before the front end of the holding piece 22 reaches the connector housing 10 (see Fig. 1). As the fitting guide portion 21 A is inserted into the retainer insertion hole 15, the retainer 20 is positioned preferably in substantially upward/downward (or lateral) direction and substantially forward/backward (or longitudinal) direction in the connector housing 10. As the insertion of the fitting guide portion 21 A further advances, the retainer 20 is more stably oriented preferably with respect to substantially upward and downward (or lateral) directions and substantially forward and backward (or longitudinal) directions. When the posture of the retainer 20 is stabilized, the front end of the holding piece 22 starts to be fitted in the guide groove 16. The holding piece 22 expands elastically and rides on the locking projection 17. When the retainer 20 reaches the temporary locking position, the holding piece 22 restores towards, preferably substantially to the original posture elastically, and the temporary locking groove 29A engages the locking projection 17. In this manner, the retainer 20 is held at the temporary locking position (see Fig. 2). In this state, the terminal 30 is or can be inserted into the cavity 14 from the rear side thereof. The terminal 30 reaches the predetermined position smoothly inside the cavity 14 without interfering with the retainer 20, and the lance 34 thereof is locked to the receiving portion 14A of the cavity 14. Then, the terminal 30 is pulled rearward. If the terminal 30 is prevented from being moved rearward, an operator finds that the lance 34 has been reliably locked to the receiving portion 14A of the cavity 14 primarily. When the lance 34 has been locked to the receiving portion 14A of the cavity 14, as shown in Fig. 8, the receiving surface 31 of the terminal 30 substantially faces the retainer installing hole 15 and is substantially located in correspondence to the inclination range S of the guide surface 26 of the retainer 20. If the terminal 30 has been inserted at a position deeper than the position at which the lance 34 of the terminal 30 is locked to the receiving portion 14A, the receiving surface 31 is located within the inclination range S or at a position forward from the inclination range S (see Fig. 11). When the receiving surface 31 is located at the position forward of the inclination range S, the lance 34 of the terminal 30 is locked to the receiving portion 14A by pulling it rearward. Thus, the function of locking the terminal primarily can be secured. Thereafter, the retainer is pressed to move it to the locking position. At this time, the holding piece 22 rides across the locking projection 17 while the holding piece 22 is expanding elastically (see Fig. 3). When the retainer 20 reaches the locking position, the main locking groove 29B engages the locking projection 17. In this manner, the retainer 20 is held at the locking position (FIG. 4). In the process of pressing the retainer 20 into the locking position, when the edge 32 of the receiving surface 31 of the terminal 30 is located within the inclination range S of the guide surface 26, the guide surface 26 substantially contacts the edge 32 obliquely, and the terminal 30 is pressed forward by the inclination thereof. When the guide surface 26 is dislocated from the edge 32 of the receiving surface 31, the locking portion 24 substantially contacts the receiving surface 31 from the rear side. Consequently, the terminal 30 is locked in the secondary locking state and thus removal thereof can be reliably prevented (see Fig. 9). As shown in Fig. 12, let it be supposed that the terminal 30 is not inserted into the predetermined position. In this case, when the receiving surface 31 of the terminal 30 is located within the inclination range S of the guide surface 26, the edge 32 is pressed forward by the guide surface 26 when the retainer 20 is pressed into the locking position. As a result, the terminal 30 is moved to the predetermined primary locking position. When the terminal 30 is inserted in a small amount and when the receiving surface is located rearward from the inclination range S of the guide surface 26, the contact surface 27 substantially contacts the side surface of the terminal 30. Thus, it is impossible to press the retainer 20 further toward the locking position. In this manner, the operator can find the presence of the terminal 30, i.e. whether it is correctly, sufficiently or incorrectly inserted. In the state where the retainer 20 is locked at the locking position, the guide portion 21 A penetrates through the retainer installing hole 1 5 and projects on the outer surface of the connector housing 10, thus contacting the front surface of the seal ring 13 and preventing the removal of the seal ring 13. In this manner, the removal of the seal ring 13 can be prevented reliably throughout its circumference by the connection portion 28, the holding piece 22, and the guide portion 21 A. As described above, in the embodiment, the guide portion 21A is formed at the front end of the highly rigid removal prevention portion 21 of the retainer 20. The guide portion 21 A engages the connector housing 10 earlier than the holding piece 22, thus placing the retainer 20 in position. Therefore, it does not occur that the front end of the holding piece 22 strikes against the outer surface of the connector housing 10. Consequently, it is possible to prevent the holding piece 22 from being deformed or damaged. In the state where the retainer 20 is locked at the locking position, in the side opposite to the side at which the retainer 20 is installed on the connector housing 10, the guide portion 21 A prevents the removal of the seal ring 13. That is, the guide portion 21A serves as a removal prevention function. Thus, it is unnecessary to provide a component part dedicated for removal prevention. Therefore, it is possible to prevent the removal of the seal ring 13 reliably. The present invention is not limited to the embodiment described with reference to the drawings, but embodiments described below are included in the technical scope of the present invention as defined in the claims. Further, embodiments described below can be made in various modes without departing from the scope of the present invention as defined in the claims. (1) In the embodiment, the guide portion of the retainer prevents the removal of the seal ring, but in the present invention, the guide portion may have a removal prevention function. (2) In the embodiment, the connector of waterproof type having the seal ring has been described. But the present invention is applicable to a connector of non-waterproof type.

Claims: A connector comprising a connector housing (10) into which at least one terminal (30) can be inserted; and a retainer (20) which can be installed on the connector housing (10) and prevent removal of the terminal (30), wherein the retainer (20) has: a removal prevention portion (21) which can be inserted into the connector housing (10) and locked to the terminal (30); a holding piece (22) which can hold the retainer (20) at a predetermined installing position; and a guide portion (21A) formed at a front end of the removal prevention portion (21) and projecting forward from an extended end of the holding piece (22) in the direction in which the retainer (20) is installed on the connector housing (10) characterized in that the holding piece (22) expands elastically during installation on the connector housing (10). A connector according to claim 1, wherein the holding piece (22) extends in the shape of a cantilever in a direction in which the retainer (20) is installed on the connector housing (10). A connector according to one or more of the preceding claims, wherein the holding piece (22) can be installed on the connector housing (10) along an outer surface of a body (11) hereof. A connector according to one or more of the preceding claims, wherein the at least one terminal (30) can be inserted from a rear side of the connector housing (10). A connector according to one or more of the preceding claims, comprising a waterproof seal ring (13) installed on a periphery of a body (11) of the connector housing (10), wherein the retainer (20) is installed on the connector housing (10) such that a guide portion (21A) of the retainer (20) penetrates through the connector housing (10), and the guide portion (21A) projects at a position of the periphery of the body (11) of the connector housing (10) such that the guide portion (21A) prevents removal of the seal ring (13). A connector according to one or more of the preceding claims, wherein the removal prevention portion (21) can be inserted into the connector housing (10) and locked to the terminal (30) by means of at least one locking portion (24); wherein the locking portion (24) comprises a guide surface (26) being arranged at an angle different from 0° or 180° with respect to an insertion/removal direction (I/R) of the terminal (30) for engaging a receiving surface (31) of the terminal (30) while the retainer (20) is being moved to its locking position thereby pressing the terminal (30) in its insertion direction. A connector according to claim 6, wherein the retainer (14) is insertable into a retainer installing hole (15), and wherein the size relationship between the terminal (30) and the cavity (14) is so set that when the terminal (30) reaches a predetermined primary locking position (Fig. 10) the receiving surface (31) is located inside the retainer installing hole (15). A connector according to claim 6 or 7, wherein an inclination range (S) of the terminal (30) on the guide surface (26) of the retainer (20) is so set (Fig. 8) as to cover the movable range of the receiving surface (31) based on the accumulative tolerance of the size tolerance of each of the connector housing (10), the retainer (20), the terminal (30) and the cavity (14). A connector according to one or more of the preceding claims 6 to 8, wherein the locking portion (24) comprises a contact surface (27) for engaging the terminal (30) while the retainer (20) is being moved to its locking position when the terminal (30) is insufficiently inserted, in particular when the receiving surface (31) thereof is located rearward from an inclination range (S) of the guide surface (26).

Inventors: KUBO AKINOBU, VARGAS MARQUEZ JULIO CESAR, KUBO, AKINOBU, VARGAS MARQUEZ, JULIO CESAR, Kubo, Akinobu, Sumitomo Wiring Systems, Ltd., Vargas Marquez, Julio César
Applicants: SUMITOMO WIRING SYSTEMS, VOLKSWAGEN AG, SUMITOMO WIRING SYSTEMS, LTD., VOLKSWAGEN AKTIENGESELLSCHAFT
Application year: 2000
Main classification: H01R13
IPC codes: H01R13