Electrical connector for locked connection of socket-type contacts

The connector has a first housing element (1) and a second, complementary housing element. The latter has a row of connecting passages in each of which sits a socket type electric contact member. The first housing element (1) has a row of connecting passages each arranged to receive a plug type electric contact member. The latter has a contact part adapted to be plugged into a socket type contact member of the second housing element, a body with a notch, and means for fastening an electric lead. Each connecting passage has at least one locking member (12) in the form of an elastic tongue with at least one locking projection to engage in the notch of the plug contact member. Slit openings are formed between the locking members to receive projections of a locking key (31). The key (31) can be held in at least two positions. It has a pre-locking position where the projections (35) are outside the slits, and a locking position where the projections (35) are in the slits. In the first position, the locking members can be freely moved away. In the second position the locking members are blocked. The first housing element (1) is aligned so as to receive the locking key (31) at its end (23) to engage with the second housing element. The key (31) has a wall (32) with a row of openings (33). These are brought into alignment with the connecting passages of the two housing elements to enable the plug and socket members to be connected. The key (31) has, on its side, at least one sprung flap (45) which extends from the surface of the key (31) and can be moved into and out of a seat (47) in the key (31). The flap (45) is arranged such that in the pre-locking position, it extends beyond the end (23) of the first housing element (1) which cooperates with the second housing element, thus preventing the two housing elements being locked together. In the locking position, the flap (45) is recessed into the seat (47) allowing the housing elements to be locked together.