Patent ID: 8048099

Claim:
Surgical obturator for puncturing a body wall, comprising: a tubular housing with a distal tapering rounded frusto-conical insertion area with an s-shaped slot along a terminal distal end, a knife comprising a knife body formed in the shape of a helix and a cutting edge formed on the knife body, the cutting edge of the knife following the shape of the knife body and extending in the shape of a helical line outwards from a terminal tip of the obturator in the direction of opposite sides and backwards from the tip in two sections, a projection of the helical line-shaped cutting edge onto a plane extending perpendicularly to a longitudinal axis of the obturator being S-shaped, the two sections of the cutting edge at the opposite sides of the terminal tip merging without any sharp bend in a region of the terminal tip, so that in the region of the terminal tip the cutting edge is arranged in a center of the knife and extends transversely to the longitudinal axis of the obturator, the two sections of the cutting edge outside of the region of the terminal tip being arranged on an outer convex side of the knife body, and the two sections of the cutting edge at the opposite sides of the terminal tip being transferable into each other's position by rotation through 180° about the longitudinal axis of the obturator wherein the cutting edge of the knife body projects through the s-shaped slot of the insertion area of the housing.