Self-damaged disposable syringe

The utility model relates to a self-damaged disposable syringe, which mainly comprises an injection cylinder 1, a push rod 2 provided with a cross-shaped cross section and positioned in the injection cylinder, a piston 7 positioned on the front end of the push rod, elastic sheets 5 positioned between the inner wall of the injection cylinder and the rod wall of the cross-shaped push rod and a retreat stopping gear 6 for the elastic sheets, and the retreat stopping gear is positioned on a spine 3 of the cross-shaped push rod and between the elastic sheets. The utility model is characterized in that the cross sections of the elastic sheets 5 are folded into a star shape, grooves of the star shaped elastic sheets are clamped on a spine 3 of the cross-shaped push rod 2, blades spread on both sides of the grooves are attached on another two mutually connected spines 3 of the cross-shaped push rod 2, and three points 4 of the tail parts of the elastic sheets are in the shape of claw. The utility model has the advantages of simple structure, simple processing, etc. The self-damaged disposable syringe which is suitable for any volume can be conveniently processed because of the structure design of the elastic sheets with the star-shaped cross sections.