Safety syringe

Abstract

A syringe apparatus and process for using the same is provided, the syringe apparatus having a barrel, a plunger movable within the barrel, a needle assembly attached to an end of the barrel and having a passageway therethrough, a deformable base positioned within the barrel, flexible supports included on the deformable base, a spring within the passageway of the needle assembly, a hollow needle passing through the passageway, an enlarged head on the needle, and a rupturable web on an end of the plunger, whereby when the plunger moves through the barrel toward the needle assembly, a fluid can be moved from the barrel through the hollow of the needle, and continued movement of the plunger flexes the supports and moves the deformable base downwardly until such time a sufficient force is imparted to the rupturable web by the enlarged head to tear the web, the deformable base then releasing the needle due to force applied by the spring to project the needle into the interior of the plunger. Seals are provided for making a liquid impervious seal on both ends of the syringe after the needle is retracted. The seal on the end left open by needle retraction is a closing member which can be used to seal off the opening without placing a user's hands in front of the opening. The syringe includes indicia that is revealed upon needle retraction to label the syringe as a biohazard. A syringe apparatus using a deformable base, enlarged needle head and needle assembly of an alternative embodiment is also provided wherein sacrificial supports in the needle assembly are utilized and severed by the deformable base.

1 - 39 . (canceled)  
   
   
       40 . A process for retracting a needle at the completion of subcutaneous injection with a hypodermic syringe, comprising the steps of: 
 forcing a plunger of said syringe downwardly to force a needle support deformable base downwardly and sever sacrificial supports;    forcing an end portion of said needle to tear a base portion of the plunger; and    propelling said needle into a hollow of said plunger such that said needle is contained entirely within said plunger.    
   
   
       41 . A syringe comprising: 
 a barrel having a first end and an opposite second end;    a plunger having a forward end and movable within the barrel from the second end of the barrel towards the first end, the plunger having a hollow interior communicating with the forward end;    a deformable base mounted within the barrel intermediate the first and second end;    sacrificial supports in the barrel for supporting the deformable base within the barrel;    a hollow needle having a pointed front, extending through the first end of the barrel and a rear end received within the deformable base;    energy storage means positioned in the barrel between the first end and the deformable base and in engagement with the needle; and    a rupturable boot on the forward end of the plunger; whereby a fluid is moved from within the barrel through the needle as the plunger moves through the barrel to the deformable base, and when the rupturable boot contacts the deformable base, continued movement of the plunger moves the deformable base toward the first end, the rear end of the needle thereby causing the boot to tear and losing contact with the deformable base to allow the energy storage means to eject the needle into the interior of the plunger.    
   
   
       42 . A syringe apparatus comprising: 
 a barrel;    a plunger movable within said barrel;    a needle assembly attached to an end of said barrel and defining a passageway therethrough;    a deformable base positioned within said barrel adjacent said needle assembly and defining a passage therethrough, said deformable base forming a liquid tight seal between said base and said barrel;    energy storage means within said passageway;    a hollow needle passing through said passageway; an enlarged head on said needle engaged within said passage of said deformable base; and    a rupturable web on an end of said plunger for moving a fluid within said barrel through the hollow of said needle when said plunger is moved through said barrel toward said needle assembly;    whereby when said plunger moves through said barrel toward said needle assembly, a fluid can be moved from said barrel through the hollow of said needle, and continued movement of said plunger moves said deformable base downwardly until such time as sufficient force is imparted to said rupturable web by said enlarged head of said needle to tear said rupturable web, said deformable base then releasing said needle with said enlarged head due to force applied thereto by said energy storage means to project said needle with said enlarged head into the interior of said plunger.    
   
   
       43 . The apparatus according to  claim 42  wherein said enlarged needle head is cylindrical.  
   
   
       44 . The apparatus according to  claim 42  wherein said deformable base is cylindrical.