Seat belt buckle

Claim 1

A seat belt buckle comprising: a base member adapted to connect to one end of a seat belt, having an opening at the front end thereof, for passing a tongue connected to another end of a seat belt therethrough; a latch member rotatably provided within said base member, said latch member including an engagement portion formed substantially at the center thereof, wing-shaped pivot portions at each side, a front trapezoidal portion, and a rear projecting portion; a spring member provided between said base member and said latch member so as to urge said latch member upwards; a casing for covering said base member, formed with a front opening for passing the tongue therethrough and a top opening; a releasing plate rotatably provided within said casing and always urged by means of a spring, said releasing plate formed with an actuating portion to press down said latch member; a holding member secured on said base member, said holding member formed with a guide opening; and, a slider integrally formed with a projecting head portion adapted to engage with said guide opening and a supporting means at the front of said slider, said slider being arranged within said holding member and urged forwardly by means of a spring which is disposed between said holding member and the rear surface of said slider so that said slider is normally located at the front end of said holding member and said supporting means contacts the under surface of said trapezoidal portion of said latch member when the tongue is not inserted, thereby preventing said latch member rotating until the tongue is completely inserted.