Safety trocar penetrating instrument with safety shield having faceted distal end

Claim 1

A safety trocar penetrating instrument comprising an elongate, tubular portal sleeve having a distal end and a proximal end; housing coupled with said proximal end of said portal sleeve and having valve therein for controlling fluid flow through said housing and said portal sleeve and for allowing passage of instruments therethrough; a trocar disposed within said portal sleeve and having a longitudinal axis, a proximal end and a solid, distal end terminating at a sharp tip beyond said distal end of said portal sleeve for penetrating tissue said trocar distal end including a plurality of angled flat sides joined at edges; a safety shield disposed between said portal sleeve and said trocar and having a proximal end and a distal end and being movable between an extended position with said safety shield distal end protruding distally of said trocar tip and a retracted position with said safety shield distal end disposed proximally of said trocar tip to expose said trocar tip; hub abutting said housing for receiving said proximal ends of said trocar and said safety shield, said trocar and said safety shield passing through said valve in said housing; bias means for biasing said safety shield toward said extended position and for permitting said safety shield to move proximally to said retracted position in response to a proximally directed force applied to said safety shield distal end, said bias means returning said safety shield to said extended position when the force applied to said safety shield distal end is removed; and stop means for limiting proximal movement of said safety shield; wherein each of said angled flat sides of said angled distal end is disposed at an acute angle with the trocar longitudinal axis and said safety shield distal end includes an external surface; wherein said stop means includes an internal surface on said safety shield distal end and an external surface on said trocar for matingly, cooperatively engaging said internal surface to limit proximal movement of said safety shield; wherein said safety shield external surface includes a plurality of flat sides equal in number to said plurality of trocar distal end sides and joined at junction lines aligned with said edges in said retracted position and wherein each of said flat sides of said safety shield external surface is disposed in said retracted position at an acute angle with the trocar longitudinal axis that is substantially the same as the acute angle of each of said flat sides of said trocar.