Patent ID: 7878377
Filing Date: 2011-02-01
Classification: B05C,F04B

Abstract:
1. A plunger for a syringe of a liquid dispenser for pressurizing a liquid material contained in the syringe by compressed air to discharge the liquid from an outlet provided in the syringe, comprising: a tapered front section having a rear end, an outer diameter of the rear end being slightly smaller than an inner diameter of the syringe; a cylindrical drum section comprising a continuation of the rear end of the tapered front section, a rear end of said cylindrical drum section having an outer diameter substantially the same as the inner diameter of the syringe, a rear end of said cylindrical drum section being open, the open end of the cylindrical drum section receiving compressed air from the syringe for pressurizing the liquid material contained in the syringe to discharge the liquid from the outlet in the syringe; and a collar member coupled with a circumferential surface of the cylindrical drum section, said collar member comprising two annular curved surface sections configured to maintain close sliding contact with different inner surface regions defined along a circumferential direction of the inner wall surface of the syringe, a first longitudinal end of the collar member being circumferentially joined to the cylindrical drum section at the open end of the cylindrical drum section.