Connector

This Application claims the benefit of the priority of Japanese Application 6-202746, filed Aug. 3, 1994.

The present Invention relates to a connector provided with a retainer, more specifically, to a connector having a retainer which is engageable with two types of projections to enable it to shift between a first locking position and a second locking position.

In order to prevent terminal fittings from releasing, there has been developed a connector provided with a retainer as shown in FIG. 1. A plurality of cavities 3 extending in the lateral direction and open to the opposite front and rear walls is formed in housing 1 of the connector. A corresponding plurality of openings 10 in communication with cavities 3 is formed in the upper and lower surfaces thereof. Retainers 8 are disposed above and below housing 1 and are connected therewith via hinges 11. The retainers 8 are movable toward and away from housing 1. Retainers 8 are externally mountable on housing 1 and are provided with a pair of side members 12 at opposite sides, the members being deformable so as to widen the spacing therebetween. Each side member 12 is formed with window 13. On the other hand, recesses 15, engageable with corresponding side members 12, are formed at opposite side surfaces of housing 1. As shown in detail in FIG. 8, two types of projections (first locking projection 17 and second locking projection 18) are formed in each recess 15. When projections 17 engage windows 13, locking portions of retainers 8 enter openings 10, but do not enter cavities 3. In this first locking position, the insertion and withdrawal of terminal fittings 5 are permitted. Retainers 8 are moved toward housing 1 while widening the spacing between each pair of side members 12 so that both projections 17 and 18 are in windows 13. Then, locking portions 9 enter deeply into cavities 3 and engage terminal fittings 5, thereby preventing terminal fittings 5 from coming out (second locking position).

As described above, when retainers 8 shift from the first locking position, where only projections 17 are in windows 13, to the second locking position, where both projections 17 and 18 are in the windows 13, the pairs of side members 12 deform to widen the spacing between each pair. This shift of retainers 8 is shown in detail in FIGS. 9(a) to 9(c). While windows 13 of retainer 8 shift from the first locking position (as shown in FIG. 9(a)) to the second locking position, windows 13 are at least momentarily free of both projections 17 and projections 18 as shown in FIG. 9(b). Accordingly, unless the movement of retainers 8 is carefully controlled, they may be completely disengaged from housing 1, resulting in a cumbersome operation of having to mount retainers 8 on housing 1 again.

The Invention was developed in view of the above problem, and an object thereof is to provide a connector with a retainer which is not disengageable therefrom while it is moved from the first locking position to the second locking position.

In practicing the Invention to achieve the foregoing object, the height of the second locking projections is made less than the height of the first locking projections. Therefore, as the retainers move from the first locking position to the second locking position, the windows are still partially engaged by the first locking projections. Thus, the retainer can shift to its second locking position without danger of being released from the housing.

In the accompanying drawings, constituting a part hereof and in which like reference characters indicate like parts;

FIG. 1 is a perspective view of a prior art connector;

FIG. 2 is an enlarged partial side view of the connector with the retainer in its first locking position;

FIG. 3 is an enlarged partial side view of the connector with the retainer in its second locking position;

FIG. 4 is a side view in section of the connector with the retainer in its first locking position;

FIG. 5 is a side view in section of the connector with the retainer in its second locking position;

FIG. 6 is an enlarged perspective view showing the first and second engagement projections;

FIGS. 7(a) to 7(c) are sections showing the process of engagement of a side member by the projections;

FIG. 8 is a perspective view of the first and second engagement projections in a prior art connector;

FIGS. 9(a) to 9(c) are sections showing the process of engagement of a side member by the projections in the prior art connector.

Hereafter, the Invention is described in detail with respect to FIGS. 2 and 7; however, reference is made to FIG. 1 as regards the prior art features thereof.

Housing 1, unitarily formed of synthetic resin, is a female connector housing and carries fitting portion 2 which is complementary to an unillustrated male connector. Housing 1 contains a plurality of cavities 3 for accommodating terminal fittings 5. Cavities 3 extend in the forward/backward direction, are open to the opposed front and rear walls, and are separated by partition walls 4. Deflectable lance 6, engageable with inserted terminal fitting 5, is formed in each cavity 3. The leading end of each lance 6 is partially cut away to form engaging portion 7 to engage corresponding terminal fitting 5. Terminal fittings 5 are female terminal fittings and each is provided, at its leading end, with hollow connecting portion 5a into which the leading end of an unillustrated corresponding male terminal fitting is inserted. Engaging hole 5b at the lower surface of connecting portion 5a can be penetrated by lance 6. Jaw portion 5c, engageable by corresponding locking portion 9 of retainer 8, is formed at the upper surface of connecting portion 5a.

Retainers 8 are located above and below housing 1 and are coupled therewith via elastically deformable hinge members 11. Both retainers 8 are preferably unitarily formed with housing 1 in vertical symmetry. In each of the upper and lower surfaces of housing 1, a plurality of slits 10 extends in parallel relationship over a specified distance backward from fitting portion 2. Slits 10 correspond to cavities 3, and communicate therewith. Locking portions 9 are projectable into cavities 3 through openings 10, are arranged at the same pitch as cavities 3 along the longitudinal direction of retainers 8, and are in the form of projections tapered from their leading ends. They do not project into cavities 3 when retainers 8 are in their first locking positions, thereby permitting the insertion and withdrawal of terminal fittings 5. When retainers 8 are in their second locking positions, locking portions 9 project deeply into cavities 3 and engage jaw portions 5c of corresponding terminal fittings 5 as shown in FIG. 5. In this way, terminal fittings 5 are doubly locked by engagement by lances 6 and locking portions 9 of retainer 8; thus, they are securely retained in cavities 3.

A pair of side members 12 is formed at the opposite sides of each retainer 8, and the spacing between the pair of side members 12 is such that they can engage recesses 15 in the side walls of housing 1. Further, each pair of side members 12 is permitted to undergo elastic deformation so as to widen the spacing therebetween, and window 13 in the form of an oblong hole is provided in each of side members 12. Furthermore, a pair of projections 14 is formed on the surface of each retainer 8 facing fitting portion 2. Projections 14 engage recesses (not shown) formed in housing 1 when retainers 8 are in their second locking positions, thereby preventing undesired lifting of retainers 8.

On the opposite side surfaces of housing 1, recesses 15 are located in positions where side members 12 are fitted. The bottom surface (in a vertical direction) of each recess 15 is slanted, has a specified downward inclination, and acts as guide surface 16 for guiding the shifting of corresponding retainer 8 from the first locking position to the second locking position. In each recess 15, projections 17 and 18 project in a horizontal direction to hold retainer 8 in its first and second locking positions and are parallel to the inclination of guide surface 16. Recesses 15 are arranged symmetrically so as to correspond to vertically symmetrically disposed retainers 8.

Projections 17 and 18 have the same width (dimension W in FIG. 2), which is substantially equal to the width of window 13. Further, the distance defined by the outer ends of projections 17 and 18 is substantially equal to the entire length of window 13. Accordingly, window 13 is engageable with projection 17 only, as shown in FIG. 2 (first locking position), and is also stably engageable with both projections 17 and 18, as shown in FIG. 3 (second locking position). In order to conform to the arcuate ends of window 13, both ends of projection 17 and the lower end of projection 18 in FIGS. 2 and 3 have a corresponding arcuate shape. Further, height H2 (in the projection direction) of projection 18 is slightly less than the thickness of side member 12, and is also less than the height of projection 17 (H1>H2). Thus, even while side member 12 moves over projection 18 so as to fit projection 18 in window 13 (FIG. 7(b)), projection 17 engages window 13 by a specified engagement margin. This engagement margin is such that the disengagement of retainer 8 from housing 1 is effectively prevented. Furthermore, the surface of projection 18 facing projection 17 is slanted surface 18a to assist retainer 8 in moving smoothly over projection 18.

When the connector is formed, retainers 8 are held in positions away from housing 1 as shown in FIG. 1 and are brought to their first locking positions prior to the insertion of terminal fittings 5. More specifically, hinges 11 are bent to bring retainers 8 closer to housing 1, and side members 12 enter recesses 15 to fit projections 17 in windows 13 (FIG. 7(a)). Since respective locking portions 9 do not enter cavities 3 at this stage, terminal fittings 5 can be smoothly inserted. Inserted terminal fittings 5 cause respective lances 6 to deflect out of cavities 3, but lances 6 return to their original shape thereafter because of their elasticity, with the result that engaging portions 7 of lances 6 engage holes 5b, thereby partially locking terminal fittings 5.

Subsequently, retainers 8 are moved into their second locking positions so that both projection 17 and projection 18 enter windows 13. As a result, retainers 8 are fixed in their second. locking positions. Since respective locking portions 9 of retainers 8 project into cavities 3 and engage jaw portions 5c of corresponding terminal fittings 5 in this position, terminal fittings 5 are retained so that they cannot come out of cavities 3.

While retainers 8 shift from their first locking positions to their second locking positions, side members 12 are displaced while being guided by guide surfaces 16 of recesses 15 and move over projections 18 while undergoing deformation to widen the spacing therebetween. Since windows 13 remain engaged by projections 17 due to the greater height thereof, the undesired disengagement of retainers 8 from housing 1 is avoided. When windows 13 have passed. over projections 18, side members 12 return to their original shape due to their elasticity. As a result, windows 13 are engaged by both projections 17 and 18 and retainers 8 are securely held in their second locking positions. Thus, retainers 8 cannot be inadvertently disengaged from housing 1 while shifting from their first locking positions to their second locking positions.

Various changes and modifications may be made in the invention without departing from the spirit thereof. For example, although projections 17 and 18 are fitted in one window 13, separate windows 13 may be formed therefor. In this case, window 13 for projection 17 is preferably an oblong hole having a sufficient length to permit the sliding movement of retainer 8. Alternatively, the Invention may be applied to male connectors, or the number of contacts, the number of hinges, etc. may be varied as desired.

These and other changes may be made while remaining within the scope of the Invention, which is not to be limited except by the character of the claims appended hereto.