Patent ID: 6527742
Filing Date: 2003-03-04
Classification: A61M

Abstract:
In a safety syringe which includes a housing having a bore which extends from a distal end of said housing to a proximal end of said housing; a barrel having a distal end located in said housing and a proximal end located externally of said housing, said barrel being mounted for reciprocating movement within said housing such that said barrel is movable between a retracted position, in which said distal end of said barrel is located proximate said proximal end of said housing, and an extended position, in which said distal end of said barrel is located proximate said distal end of said housing; a needle assembly attached to said barrel at said distal end thereof, said needle assembly having a needle attached thereto; a ring mounted to said barrel about said distal end thereof, said ring being rotatable relative to said housing and to said barrel and including a first tab and a second tab circumferentially spaced from said first tab; and urging means for urging said barrel toward its said retracted position, the improvement wherein said housing has an interior wall which includes a first raised segment having a first open area and a second open area circumferentially spaced from said first open area, said first raised segment having a first ramp which protrudes into said first open area and which is sized and shaped so as to allow said first tab to slide therealong, said first open area including a second raised segment having a second ramp, which protrudes into said first open area and which is sized and shaped so as to allow said first tab to slide therealong, and a first stop, which protrudes into said first open area and which is positioned adjacent said second ramp, said second raised segment being sized and shaped so as to form a first groove on one side thereof and a second groove on an opposite side thereof, said first groove extending from said proximal end of said housing to said distal end of said housing and being sized and shaped so as to slidably receive said first tab, said second groove extending from said proximal end of said housing to said distal end of said housing and being sized and shaped so as to slidably receive said first tab, said second open area extending from said proximal end of said housing to said distal end of said housing and being sized and shaped so as to slidably receive said second tab, said first raised segment having a third ramp, which protrudes into said second open area and which is sized and shaped so as to allow said second tab to slide therealong, a fourth ramp, which protrudes into said second open area and which is sized and shaped so as to allow said second tab to slide therealong, a second stop, which protrudes into said second open area and which is positioned adjacent said fourth ramp, and locking means, positioned so as to be engageable by said first tab, for locking said barrel in its said retracted position such that said needle is concealed in said housing.