Syringe

摘要

A syringe comprising a cylindrical barrel with a wall at one end with a nozzle and with a threaded actuating rod extending from its other end. The rod has a piston at the end thereof within the barrel, the piston being in fluid tight engagement with the inner wall of the barrel, and has a knob at its opposite end for rotating the rod. The rod also carries a collar with threads which mate with the rod threads, and the collar has slots which engage projections on the barrel and prevent movement of the collar relative to the barrel but which permit the collar to be disengaged readily from the barrel. Rotation of the rod causes movement of the piston axially of the barrel when the collar is engaged, but the rod can be moved axially without rotation when the collar is disengaged.