Patent ID: 6837874

Claim:
A safety trocar assembly having: a longitudinal central axis; a portal unit with elongated, tubular cannula having an open distal end; a trocar unit having an elongated obturator adapted to be removably inserted through said cannula, having a handle on a proximal end, and a penetrating end on a distal end, said penetrating end exposed through said open distal end of said cannula and having a cutting means for making an orifice in body cavity wall, a penetrating apex, and a sloping side wall that are immovable relative to said obturator; a protector means situated on said obturator and having a penetrating apex shield adapted to actuate between a retracted position in which said penetrating apex is open and an extended position in which said penetrating apex is closed by said penetrating apex shield and in the projection onto the plane normal to said longitudinal axis said sloping side wall surrounds said penetrating apex shield; said penetrating apex shield surrounds said penetrating apex and has distal edge forming means for precluding the introduction, jamming, and engagement of tissue fibers of body cavity wall between said penetrating apex shield and said penetrating apex; bias means for biasing said penetrating apex shield toward said extended position and for permitting said penetrating apex shield move to said retracted position in response to a proximally directed force applied to said penetrating apex shield distal edge; said bias means returning said penetrating apex shield to said extended position when the force applied to said penetrating apex shield distal edge is removed, that occurs when said penetrating apex and said penetrating apex shield distal edge have entered a patient's body cavity, however, before said penetrating end has been fully inserted into body cavity.