Patent ID: 6162200
Filing Date: 2000-12-19
Classification: A61M

Abstract:
A syringe comprising:a tubular barrel having an open proximal end, a distal end with a fluid expelling passage defined therein, and a barrel chamber;a seal being disposed within said barrel chamber a predetermined distance away from said open proximal end in fluid-tight and axially-sliding engagement with said barrel chamber, so that fluid held in said barrel chamber between said fluid expelling passage and said seal can be expelled from said barrel chamber to the outside via said fluid expelling passage by sliding said seal towards said fluid expelling passage; andsaid seal defining at least two diametrically enlarged portions at axially spaced apart portions on said seal so as to be respectively in abutment with the inner wall of said barrel chamber and a concave portion between adjacent diametrically enlarged portions of said at least two diametrically enlarged portions for defining a clearance relative to said inner wall of said barrel chamber;wherein lubricant film exists at interfaces between said at least two diametrically enlarged portions of said seal and said inner wall of said barrel chamber, and lubricant is filled in said clearance.