Rotary ram collet lock needle point guard

摘要

A needle point guard having a movable collet to lock the needle in place in the shielded position is provided. The needle point guard of this invention includes a housing, a collet, a rotary ram, a threaded cam fixed to the rotary ram, a spring disposed between the rotary ram and the housing and a trigger catch to hold the threaded cam in place against the force of the spring. The spring is wound when the needle is in the unshielded position. When the needle is withdrawn into the needle point guard, the trigger catch pivots to allow the spring to rotate the threaded cam. This rotation is translated into axial motion by the treads on the threaded cam and threads formed on the inside of the housing. This axial motion forces an annular flange on the collet to bite down on the needle, to thus hold the needle in place in the shielded position.