| 摘要 |
H:/scg/lntenvovecn/NRPorbl/DCC/SCG/6373140 l.DOC-29/05/2014 A syringe assembly, comprising: a hollow barrel with a nozzle at a distal end of said barrel, said barrel defining at least one pair of apertures; a plunger slidably movable within said barrel, said cap and said barrel at least partially defining a fluid chamber therebetween, wherein said plunger has at least two flanges protruding laterally outward therefrom; a resilient cap attached to the distal end of said plunger and engaging an interior surface of said barrel; a hollow needle in fluid communication with said fluid chamber and retractably mounted with respect to said barrel; a spring retainer having a retainer body with at least one pair of projections each protruding laterally outward from said body into a respective one of said at least one pair of apertures thereby locking said spring retainer to said barrel, said spring retainer body defining a longitudinally elongated passage for receiving said plunger therethrough, said spring retainer and said plunger cooperatively defining a needle-retraction channel; a needle retraction mechanism passing through said needle-retraction channel and operatively supported by said spring retainer, said needle retraction mechanism including a needle holder attached at a distal end thereof to said needle, and a spring circumscribing a portion of said needle holder and biasing said needle holder from an advanced position, in which said needle projects out of said barrel nozzle, to a retracted position, in which said needle and said needle holder are fully enclosed within said barrel; wherein said spring retainer grips said needle holder thereby retaining said spring in a compressed state between said needle holder and said spring retainer, and releases said needle holder in response to said plunger sliding to a fully advanced position, whereby said spring is allowed to expand and thereby move said needle holder to said retracted position; and wherein said spring retainer defines at least two windows each configured to receive a projection respective one of said of at least two plunger flanges when said plunger reaches said fully advanced position, whereby said plunger is locked to said spring retainer. |
