DR. EDWARD D WILLIAMS, DMD
Dentist at Crittenden St, Philadelphia, PA

5336187, Aug 9, 1994

Jun 24, 1993

8/080307

Mark Terry - Philadelphia PA
Harry G. Hughes - Roslyn PA
Edward D. Williams - Philadelphia PA

A61M 500

604110

An accident-proof syringe that has an automatically and permanently covered needle point at all times for use with clinical apparatus operably applied to a patient by way of skin puncture; this disposable non-reusable hypodermic needle assembly comprises a hollow syringe body, a piston slidably mounted inside the syringe body and defining between the closed end of the syringe body and the piston a compartment for containing a liquid to be injected or withdrawn from a person, an injection needle, the base of which is fastened to a needle support member, said support member and said piston being adapted for allowing at least partial insertion of said support member in said piston and for allowing the needle to communicate with said syringe body compartment upon said insertion, a substantially cylindrical sleeve member which is open at both ends, said needle support member being mounted at one end portion of said sleeve member, retaining means for fastening said sleeve member to the syringe body during the storage of the hypodermic needle assembly and at least until the beginning of the injection, a substantially cylindrical, inter- protective sheath member for protecting the needle, and a collapsible bellow shaped inner needle shaft cover that surrounds a portion of the needle and abuts at one end against said needle support member and at its other end against said protective sheath member to urge the protective sheath into a rest position where said sheath member protrudes outside said sleeve member and surrounds the needle tip.