US Patent 7658725 Enclosed needle device with duckbill release mechanism

An enclosed needle catheter insertion device (10) includes a catheter (12) and a needle insertion device (14) which are held together by cooperating arms (52, 53) with one or more detents (56) cooperating with a radially projecting surface (26) of the catheter hub (16). Insertion device (14) includes a guard housing (30) to enclose a needle (34) in a shielded position and a support housing (32) supporting the needle (34) for movement between a ready position, with the tip (36) of the needle (34) exposed, to the shielded position. Cooperating lock elements (47, 78) are provided for the housings (30, 32) which are positioned to define a lock actuation stage between the ready and shielded positions, whereat the needle is still within a passageway (54) defined by the cooperating arms (52, 53).