Abstract:
A locking device for a two part plug-in connector comprises two separate locking pieces (10,20), one mounted on one part of the connector and including hooks, the other mounted on a second part of the connector and comprising hook-receiving notches. One or other of the locking pieces (10,20) is movable relative to its connector part.

Description:
The present invention relates to electrical connectors of the type comprising two plug-in parts. 
     BACKGROUND 
     In general, one part of a connector comprises a plurality of male contacts cooperating with female contacts in the other part. If one of the parts of the connector is generally fixed (at the back of a rack for example), the other part is held only by cooperation between the contacts. This second part, which is subjected to the weight of the cable to which it is joined, may come loose from the first part, either due to an impact or because of incorrect plugging in. 
     OBJECT OF THE INVENTION 
     One object of the invention is to provide a locking device which prevents connectors from opening unexpectedly and provides satisfactory engagement. 
     Another object of the invention is to provide a locking device which, besides its function of clamping the parts of the connector, also acts as an index, so as to prevent the parts of the connector from being joined in erroneous fashion. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a device for locking a connector comprising a first part and a second part, one of the parts carrying contacts of a first type for cooperating with contacts of a second type carried by the other part, the connection being made by bringing a first face of one part close to a second face of the other part, wherein the first part includes a first locking piece equipped with hooked members extending perpendicularly to two edges of the first face towards the exterior of the part, said locking piece being capable of moving with respect to the first part parallel to said edges and being restored to a fixed position by a spring, the second part including a second locking piece, fixed with respect to the second part, disposed in the vicinity of the second face and comprising apertures having a shape complementary to that of the hooked members. 
     Alternatively the hooked locking piece may be fixed with respect to its connector part, while the locking piece with hook-receiving apertures is capable of moving with respect to its connector part. 
    
    
     BRIEF SUMMARY OF THE DRAWINGS 
     The invention will be clearly understood from the description given hereinafter of a preferred embodiment with reference to the accompanying appended drawings, in which: 
     FIG. 1 is an exploded view of a connector equipped with a locking device in accordance with the invention; 
     and 
     FIGS. 2a and 2b illustrate operation during connecting and locking. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 is an exploded view of the various components of a connector and of a locking member in accordance with the invention. 
     This example is a connector of which one of the parts, here the part bearing the reference 1, is fixed to a rack 2. 
     The rack is a printed circuit board. The board may be horizontal or vertical. Pins such as 3 pass through the board and the connector part 1 by way of holes such as 5. The part 1 of the connector, taking the form of a box inside which the pins 3 project, is intended to be joined to another part 6 including cavities 7 corresponding to the pins 3; at the bottoms of these cavities there are pins 8 whose ends 8a cooperate with the pins 3 in order to make the electrical contact, and whose other ends are joined to wires 9 combined to form a cable 9a which emerges from the part 6. 
     In order to lock this connector, its parts 1 and 6 are equipped with respective first and second locking members. 
     The first locking member, bearing as a whole the reference 10, is a metal piece fitted round the part 1 and comprising slides such as 11a to 11d capable of sliding in grooves 12a to 12d in the part 1. Hooked members such as 13 extend parallel to two large faces 14a and 14b of the part 1, and extend beyond the edges of this part. 
     A spring in the form of a bent resilient metal strip 15 bears both against one end of the part 1 and against a folded-over portion 16 of the piece 10. 
     It is held in place by lugs 15a and 15b which bear against the slides 11a and 11b respectively. 
     The second locking member, bearing the reference 20, is a piece surrounding the connector part 6, in the vicinity of the face facing the element 1. This piece is fastened to the part 6 by means of screws 21a and 21b passing through orifices 22a and 22b in transverse lugs 23a and 23b on the piece. The lugs rest on shoulders 24a and 24b on the part 6, which shoulders are provided with holes 25a and 25b to receive the screws 21a and 21b. 
     At its sides, the piece 20 includes notches 26 intended to cooperate with the hooked members 13. The size d of the aperture 26a of the notch is just slightly greater than the length of the hook taken from its toe 13a to its heel 13b, so as to enable the hooks to engage in the notches. 
     The manner in which the connector is used is illustrated in FIGS. 2a and 2b. 
     In order to join the two parts 1 and 6 of the connector, pressure is applied to the locking member 10 in the direction of (arrow F 1  in FIG. 2a), so that when the cavities 7 come into position facing the pins 3, the hooks 13 are facing the notches 26 and can enter therein. 
     The two parts of the connector are brought close together (arrow F 3 ), and then (FIG. 2b) the pressure on the locking member 10 is relaxed. Each hook then enters the central part of the corresponding notch. 
     It will be noted that the shape of the hooks enables introduction and locking to be automatic. 
     It will be noticed that the arrangement of the hooks and notches provides additional security, since it is impossible to connect the two elements of the connector the wrong way round. 
     In the example described, it is the part having hooks which is capable of moving in translation; naturally the part having notches could be movable, with the part having hooks then being fixed.