| 摘要 |
<p>A single use disposable hypodermic syringe (10) having a hollow elongated barrel portion (12), a piston (14) in sealing engagement and axially translatable along the barrel, a piston rod (16) secured to the piston (14) and projecting from the rearward end of the barrel (12) for use in reciprocating the piston, a walled chamber (23) disposed proximate the forward end of the barrel and plug means (24) disposed in the chamber and moveable from a rearward to a forward position. The plug (24) defines fluid passages (48) therein to allow fluid flow about the plug (24) and an annular flange (46) for maintaining the plug (24) in the rearward position upon air being passed through the fluid passages (48). The annular flange (46) also cooperates with a second portion of the chamber wall for permanently maintaining the plug (24) in the forward position. With the plug (24) in the forward position, the annular flange (46) seals the fluid passages (48) upon the piston (14) being retracted within the barrel (12) to prevent any additional liquid from being aspirated into the barrel (2) of the syringe about the plug (24) thereby rendering the syringe non-reusable.</p> |
