Lever-operated connector

Abstract: A lever-operated connector includes a pair of connector housings displaced toward each other to be connected together by rotationally loving a lever form an open position to connected position, a cam follower portion provided on one connector housing, the lever rotatably mounted on the other connector housing, a lever lock portion, and a return spring. The lock portion has a retaining pawl provided on the one connector and a retained portion provided on the lever. The cam portion has a play region for allowing the lever to return a predetermined angle from the connected position toward the open position. A surface on which the retained portion is engaged with the retaining pawl is inclined in such a direction as to hamper retraction of the retaining pawl. Furthermore, the lever is automatically brought into upstanding condition by the return spring.

Description: BACKGROUND OF THE INVENTION This invention relates to an improved lever-operated connector in which connector housings are connected together through leverage, see e.g. US-A-5 135 408. A connector of this type has an advantage that the connection and disconnection can be effected with a small force, and this concept has been applied particularly to multiterminal connectors. Its basic principle is based on the action of leverage, and such a conventional construction disclosed, for example, in Unexamined Japanese Patent Publication No. Hei. 4-627724 is broadly as follows. A typical construction of a conventional connector shown in Figs. 9 and 10, for example, is known. On the left side of Fig. 9 is a female connector housing 1 arranging more than one female terminals (not shown), whereas on the right side thereof is a male connector housing 2 arranging more than one male terminals (not shown) and having a hood portion 2a for accommodating the female connector housing 1. Cam follower pine 3 are projected from opposite (right and left) side walls of the female connector housing 1, and guide grooves 4 for receiving the cam follower pins 3 are formed in opposite (right and left) side walls of the hood portion 2a of the male connector housing 2. A lever 5 in rotatably supported by the male connector housing 2 so that the lever 5 can turn between an open position shown in Fig. 9 to a connected position shown in Fig. 10 around pivot pins 2b projected from the side walls of the male connector housing 2. Cam grooves 6 to be engaged with the cam follower pins 3 are formed in the inner surfaces of the lever 5. The cam grooves 6 are inclined so that the cam follower pins 3 can enter deep into the hood portion 2a of the male connector housing 2 in association with the pivotal movement of the lever 5. The female connector housing 1 is inserted into the hood portion 2a of the male connector housing 2 from a state shown in Fig. 9, and the lever 5 is turned in a direction of an arrow in Fig. 9. As a result, the cam follower pins 3 and hence the female connector housing 1 enter deep into the hood portion 2a by leverage through the cam grooves 6 in the lever 5, there completing the connection of both connector housings in a state shown in Fig. 10. To ensure such connection of the connector housings, a lock mechanism that locks the lever 5 in the connected position is arranged. Details of the lock mechanism is as shown in Figs. 11A and 11B. A distal end portion of the lever 5 is hollowed out square to form a retained portion 7, and a retaining pawl 8 is formed in a distal end portion of the female connector housing 1 so that the return of the lever 5 toward the open position can be prevented with the retaining pawl 8 engaged with the retained portion 7. This retaining pawl 8 is designed so as to turn in a direction of an arrow in Fig. 11A elastically through an elastic leg 9. By pressing a distal end portion 8a of the retaining pawl 8 by a finger, the retaining pawl 8 is turned to release its engagement with the retained portion 7. The surface on which the retained portion 7 engaged with the retaining pawl 8 has conventionally been defined in such a shape that the bottom surface of the retaining pawl 8 is simply extended flat as shown in Figs. 11A and 11B. However, the above-mentioned conventional structure is disadvantageous in that if a strong turning force toward the open position is exerted on the lever 5 that is in the connected position, the retaining pawl 8 is raised by the lower surface of the retained portion 7, which then causes the elastic leg 9 to be deformed elastically so as to get away from the retained portion 7. This readily puts the retaining pawl 8 in a retracting portion as shown in Fig. 11B. As a result, the engagement between the retained portion 7 and the retaining pawl 8 is to be released more readily, which does not allow the lever 5 locking function to be performed adequately, and causes the connector housings to be disconnected undesirably. Another construction of the conventional lever-operated connector is shown in Figs. 12A to 12D. Many male terminals are arranged in a male connector housing 101, and many female terminals are arranged in a female connector housing 102 to be inserted into the male connector. A lever 103 having a cam groove 103a for effecting leverage is rotatably mounted on the male connector housing 101, and a cover 104 having an engagement projection 104a is attached to the female connector housing 102. For connecting the two connector housings 101 and 102 together, the engagement projection 104a is engaged in the cam groove 103a in the lever 103 as shown in Fig. 12B, and in this condition the lever 103 is rotationally moved in a direction of an arrow described in Fig. 12B, so that the cover 104 and hence the female connector housing 102 are displaced toward the male connector housing 101 by leverage through the cam groove 103a, therefore the two connector housings connect together. In the above-mentioned construction, the cam groove 103a in the lever 103 is smoothly curved to be gradually changed in curvature so that the lever 103 can impart a downward displacing force to the engagement projection 104a at any point through the angle of rotational movement of the lever 103 from an open position (Fig. 12B) to the connected position (Fig. 12D). In this construction, for disconnecting the two connector housings form each other, the lever lock mechanism is first released to allow the rotational movement of the lever 103, and then the finger is put on the distal end portion of the lever 103, and then the lever is turned upward. However, in this operation, even when the locking by the lever lock mechanism is released, the lever is not automatically moved to a position where the finger can be easily put on the lever. Therefore, the connector housings 101 and 102 are held with one hand, and the lever 103 is forcibly turned with the finger of the other hand in the condition. Thus, this operation can never be effected with one hand. Therefore, after the connector is incorporated into a narrow space in an equipment, there has been encountered a problem that it is quite difficult to disconnect the connector. The prevent invention has been accomplished under the above circumstances, and an object of the invention is to provide a lever-operated connector which can lock a lever in a connected position surely and whose function for preventing the disconnection of connectors is excellent. Another object of the invention is to provide a lever-operated connector in which connectors can be easily disconnected from each other when the locking is released. According to the present invention a lever-operated connector is provided, said connector comprising: a pair of connector housings displaced toward each other to be connected together by rotationally moving a lever from an open position to a connected position; at least one pin provided on one connector housing for engagement with at least one groove, said groove being provided in said lever, which is rotatably mounted on the other connector housing and a lever lock portion for retaining said lever in the connected position, said lever lock portion comprising: a retained portion provided on said lever, and a retaining pawl for holding said retained portion. The lever-operated connector according to the present invention is furthermore characterized by a return spring for urging said lever toward said open position, said groove comprising a play region for said pin so as to allow said lever to return a predetermined angle from said connected position toward said open position, wherein said lever is automatically brought into an upstanding condition by the urging force of said return spring when said lever is released from said lever lock portion. When the two connector housings are connected together, with the lever disposed in the connected portion, the lever is urged toward the open position by the return spring. However, the lever is held in the connected position by the lever lock portion. In this condition when the engagement of the lever by the lever lock portion is released, the lever tends to be turned toward the open position by the return spring. In the case of the conventional lever-operated connector, the cam groove 103a of the lever 103 is smoothly curved such that the lever always imparts a downward displacing force to the engagement projection 104a , and therefore even when the lever is disposed near to the connected position, the engagement projection is still engaged with the cam groove 103a of the lever 103. Therefore, even if the lever is urged toward the open position by a return spring, the lever will not be returned from the connected position toward the open position. In contrast, in the lever-operated connector according to the present invention, the cam portion of the lever has the play region which allows the lever to return the predetermined angle from the connected position toward the open position. Therefore when the engagement of the lever by the lever lock portion is released, the lever is rotationally returned the predetermined angle by the force of the return spring. As a result, the lever is disposed in a slightly upstanding condition, and then the finger is put on the lever, so that the lever can be easily turned. As described above, in the lever-operated connector of the present invention, when the locking by the lever lock portion is released, the lever is automatically returned rotationally the predetermined angle, so that the finger can be easily engaged with the lever, thus providing an excellent advantage that the disconnection of the connector can be effected quite easily. BRIEF DESCRIPTION OF DRAWINGS Fig. 1 is a perspective view of an overall construction of one preferred embodiment of the present invention; Fig. 2 is a perspective view of a lever; Fig. 3 is a front-elevational view of a lever lock portion; Fig. 4 is a vertical cross-sectional view of the lever lock portion; Figs. 5A to 5C are views showing the process of turning of the lever and the process of movement of an pivot pin; Fig. 6 is a perspective view of the connector in a connected state; Fig. 7 is a side-elevational view showing the process of a disconnecting operation; Fig. 8 is a side-elevational view showing the process of the disconnection operation; Fig. 9 is a side view showing a conventional lever-operated connector in a disconnected state; Fig. 10 is a side view showing the conventional lever-operated connector in a connected state; Figs. 11A and 11B are sectional views showing a conventional structure for locking a lever; and Figs. 12A to 12D are schematic side-elevational views showing the conventional lever-operated connector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One preferred embodiment of the present invention will now be described with reference to Fig. 1 to 8. Fig. 1 shows an overall construction. A male connector housing 111 having male terminals (not shown) is shown at a right side of Fig. 1, and a female connector housing 112 having female terminals (not shown) is shown at a left side thereof. The female connector housing 112 is of such a size that it can be inserted into the male connector housing 111. A pair of cam follower pin. 113 corresponding to cam follower portions (only one of which is shown) are formed on and projected laterally from opposite (right and left) sides of the female connector housing 112. A pair of quide grooves 115 are formed respectively at opposite (right and left) sides of the male connector housing 111, and when the male connector housing 111 is fitted on the female connector housing 112, the cam follower pins 113 are received in the guide grooves 115, respectively. A pair of pivot pins 116 (only one of which is shown) are formed on and projected laterally from the opposite (right and left) sides of the male connector housing 111, respectively. A U-shaped lever 117 is rotatably supported on the pivot pins 116. Cam grooves 118 serving as cam portions are formed respectively in the inner surfaces of the opposite sides of the lever 117 facing the male connector housing 111, as shown in Fig. 2. When the male connector housing 111 is fitted, the cam follower pins 113 are received and engaged in the cam grooves 118, respectively. The shape of the cam groove 118 will be described later in detail, and as a whole the cam groove 118 has an arc shape whose curvature is gradually changed. During the rotational movement of the lever 117 from an open position (Fig. 1) to a connected position (Fig. 6), the cam follower pin 113 and hence the female connector housing 112 are displaced to be inserted into the male connector housing 111, thereby connecting the two connector housings together. A spring reception recess 119 in formed at the portion of the side wall of the lever 117 where one pivot pin 116 extends therethrough, and a return spring 120 comprising a coil spring is received in the recess 119. One end portion of the return spring 120 is received in a retaining groove 119a extending from the reception recess 119, and the other end portion thereof is retained by a retaining projection (not shown) formed on a side wall of the male connector housing 111. With this arrangement, the lever 117 is normally urged toward the open position by the return spring 120. As shown in Fig. 1, a retaining pawl 122 is formed on the upper surface of the female connector housing 112 through an elastic leg 123, the retaining pawl 122 being interposed between side walls 121 (see Fig. 4). When the rear end portion (the left portion in Fig. 4) of the retaining pawl 122 is pressed down, the elastic leg 123 is flexed and elastically deformed, so that the distal end portion of the retaining pawl 122 is raised. A retaining projection 124 for engagement with the retaining pawl 122 is formed on the central portion of the lever 117, and a lever lock portion 125 for retaining the lever 117 in the connected position is constituted by these portions. The shape of the cam groove 118 in the lever 117 is shown in detail in Fig. 5A to 5C. More specifically, the cam groove 118 has a pair of opposed inner surface which are arcuate as a whole. And when the female connector housing 112 in to be inserted, one (hereinafter referred to as "insertion-side cam surface 118A") of these inner surfaces is strongly contacted with the cam follower pin 113 to displace this connector housing 112 into the male connector housing 111. When the female connector housing 112 is to be disconnected, the other inner surface (hereinafter referred to as "disconnection-side cam surface 118B") is strongly contacted with the cam follower pin 113 to displace this connector housing 112 away from the male connector housing 111. In the embodiment, the portion 118B1 (an inlet portion for inserting the cam follower pin 113) of the disconnection-side cam surface 118B corresponding to the open position of the lever 117, as well as the portion 118B2 (an end portion to which the cam follower pin 113 can advance deepest) of this cam surface corresponding to the closed position of the lever 117 has a characteristic shape, which will be described later. And the remainder is smoothly continuous and is gradually changing in curvature. Namely, at the portion 118B1 corresponding to the open position of the lever 117 is flat as shown in Fig. 5A. With this arrangement, when the female connector housing 112 is merely inserted into the male connector housing 111, each cam follower pin 113 abuts against the flat portion 118B1, so that a further insertion of the female connector housing is prevented. With respect to the portion 118B2 corresponding to the connected position of the lever 117, a constant curvature portion 118B2 whose curvature is constant is provided at a region lying from this portion to a portion back toward the open portion at a predetermined angle . With this, arrangement, the lever 117 has a play region which allows the lever 117 to return a predetermined angle  from the connected position toward the open position. The operation of the above construction will now be described with respect to the case of disconnecting the connected two connectors from each other. Let's assume that the two connectors are in the connected condition as shown in Fig. 6, and that the lever 117 is retained in the connected position by the lever lock portion 125. Even in this case, the lever 117 is urged toward the open position by the return spring 120. However, the lever 117 is prevented by the lever lock portion 125 from being turned toward the open position. Here, for example, the thumb is engaged with the rear end portion of the retaining pawl 122 of the lever lock portion 125, as shown in Fig. 7, and presses it down. As a result, the elastic leg 123 is elastically deformed to raise the distal end of the retaining pawl 122, so that the retaining pawl 122 is disengaged from the retaining projection 124 of the lever 117. In this embodiment, the lever 117 is normally urged toward the open position by the return spring 120, and the lever 117 has the play region for allowing the lever to return the predetermined angle from the connected position toward the open position. Therefore, the lever 117 is immediately rotationally returned the predetermined angle under the influence of the return spring 120, then the lever 117 is stopped, as shown in Fig. 8. Therefore, the lever 117 is disposed in a generally upstanding condition as indicated in a solid line in Fig. 8, and a gap is formed between the lever 117 and the upper surface of the male connector housing 111. Therefore, the finger can be readily put on the lever 117 even if the operation is carried out with one hand. In this condition, the disconnection-Side cam surface 118B of each cam groove 118 is pressed against the cam follower pin 113, and a frictional force is exerted between the male and female terminals. The finger is put on the distal end of the lever 117, and pulls and turns the lever, so that each cam follower pin 113 of the female connector housing 112 is urged upward by the disconnection-side cam surface 118B of the cam groove 118 to be displaced toward the open position, and the female connector housing 112 is withdrawn from the male connector housing 111. As a result, the female and male terminals are disconnected from each other. Thus, in this embodiment, for disconnecting the connectors from each other, the finger is first engaged with the retaining pawl 122 to release the locking of the lever 117, so that the lever 117 is automatically brought into a generally upstanding condition. Then, the lever 117 is put on the finger, and is turned. Therefore, even if the connector is mounted in a narrow space in an equipment, it can be disconnected with one hand, and the operation including maintenance can be effected easily. For connecting the connectors together, the female connector housing 112 is inserted into the male connector housing 111, and the lever 117 is turned into the connected position, and finally the retaining projection 124 of the lever 117 is engaged with the retaining pawl 122, as is the case with the conventional construction. By doing so, each cam follower pin 113 is displaced by the cam groove 118 in the lever 117, so that the female connector housing 112 is brought into the connected position. Therefore, the operability for connecting the connectors together is not adversely affected at all. The present invention is not limited to the above embodiment, and for example the following modifications can be made. (a) In the above embodiment, although the lever is provided on the male connector housing while the cam follower pins are provided on the female connector housing, this may be reversed; that is, the lever may be provided on the female connector housing while the cam follower portion may be provided on the male connector housing. (b) In the above embodiment, although the cam follower pins (cam follower portions) are formed directly on the female connector housing, this is not always necessary. For example, a cam follower portion may be formed on a cover that is to be attached to one connector housing, in such a manner as to be engaged in a cam groove formed in a lever mounted on the other connector housing, and by turning the lever, the cover and hence the connector housing are displaced. The present invention is not limited to the embodiments described above and shown in the drawings; but the invention may be embodied while modified in various modes within such a range as not to deviate from the material part of the invention.

Claims: A lever-operated connector comprising: a pair of connector housings (111, 112) displaced toward each other to be connected together by rotationally moving a lever (117) from an open position to a connected position; at least one pin (113) provided on one connector housing (111, 112) for engagement with at least one groove (118), said groove (118) being provided in said lever (117), which is rotatably mounted on the other connector housing (112, 111); and a lever lock portion (125) for retaining said lever (117) in the connected position, said lever lock portion (125) comprising: a retained portion (124) provided on said lever (117), and a retaining pawl (122) for holding said retained portion (124), characterized by a return spring (120) for urging said lever (117) toward said open position, said groove (118) comprising a play region (118B2) for said pin (113) so as to allow said lever (117) to return a predetermined angle () from said connected position toward said open position, wherein said lever (117) is automatically brought into an upstanding condition by the urging force of said return spring (120) when said lever (117) is released from said lever lock portion (125). The connector according to claim 1, wherein said return spring (120) is a coil spring. The connector according to claim 1 or 2, wherein a side wall of said one connector housing comprises a retaining projection, and said lever (117) further comprises a spring reception recess (119), wherein one end portion of said return spring is received in a retaining groove (119a) extending from said reception recess (119), and the other end portion of said return spring (120) is retained by said retaining projection. The connector according to claim 1, 2 or 3, wherein one groove surface (118B1) is flat at a portion corresponding to the open position, and the other groove surface (118B2) is formed in a constant curvature at a portion corresponding to the connected position to be said play region of the groove portion.

Inventors: KONOYA HISASHI, SAITO MASASHI, KONOYA, HISASHI, SAITO, MASASHI, KONOYA, HISASHI, C/O SUMITOMO WIRING SYSTEMS, LTD., SAITO, MASASHI, C/O SUMITOMO WIRING SYSTEMS, LTD.
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1993
Main classification: H01R13
IPC codes: H01R13