SYRINGE

摘要

A syringe for dispensing medicaments includes a barrel with a discharge end and an open end for receiving a plunger. The plunger has a head with engagement means for receiving a plunger seal. The plunger seal is a tubular member which is severed along a generally longitudinal direction providing a slit which allows the seal to be expanded for fitting onto the plunger head. Preferably the slit has an irregularity at the forward end which provides a locking configuration which prevents the seal from being twisted away from its normally tubular shape. For metered dose application, the shank of the plunger may be threaded for the desired placement of a stop ring threaded on the shank. In one form, the ring and barrel have interlocking means to prevent the ring from moving backward when pressure is applied to the plunger after the ring has reached the barrel.