Abstract: A scalpel is provided with a blade guard which is mounted for movement between a blade-guarded position and a blade-exposed position and an actuating mechanism for the blade guard is positioned in such a way that the fingers of the surgeon automatically engage the mechanism when the scalpel is held in its normal position of use. The actuating mechanism is coupled to the blade guard through a linkage assembly which causes the blade guard to move over a substantially greater distance than the distance which the surgeon's fingers move in operating the actuating mechanism. In a preferred embodiment, the blade guard slides over a linear path, the actuating mechanism comprises a tongue-like structure integral with the scalpel, and the linkage assembly comprises a plurality of pivotally interconnected lever arms. One of the lever arms is positioned so as to be captured in a detent mechanism when the blade guard is fully retracted to its blade-exposed position.

Abstract: Apparatus for passing a fluid into or out of a warm-blooded animal which includes a fluid containing body, a needle assembly releasably mountable on the exterior surface of the body, a plunger for urging a fluid into or out of the body and an externally mounted cap or retraction device for automatically covering the needle after it has been used and preventing the needle from reentering the aperture in the body.

Abstract: A scalpel is provided with a blade guard which is mounted for movement between a blade-guarded position and a blade-exposed position and an actuating mechanism for the blade guard is positioned in such a way that the fingers of the surgeon automatically engage the mechanism when the scalpel is held in its normal position of use. The actuating mechanism is coupled to the blade guard through a linkage assembly which causes the blade guard to move over a substantially greater distance than the distance which the surgeon's fingers move in operating the actuating mechanism. In a preferred embodiment, the blade guard slides over a linear path, the actuating mechanism comprises a tongue-like structure integral with the scalpel, and the linkage assembly comprises a plurality of pivotally interconnected lever arms. One of the lever arms is positioned so as to be captured in a detent mechanism when the blade guard is fully retracted to its blade-exposed position.