Abstract: An obturator has an elongated shaft with a first shaft portion and a second shaft portion within an obturator housing. The distal end of the first shaft portion creates a first shield and the distal end of the second shaft portion creates a second shield. A blade having a piercing tip and cutting edges is interposed between the first shield and the second shield. In use, once the piercing tip passes the body wall, the first shield moves to cover the piercing tip and protect internal organs from accidental injury while the cutting edges continue to cut the body wall. Once the second shield passes through the body wall, the second shield moves to cover the cutting edges.

Abstract: Trocar seal assemblies are disclosed which consist of a helically-shaped seal positioned within a trocar's cannula; wherein, as an instrument is inserted through the central bore of the helically-shaped seal, the helically-shaped seal expands, thereby increasing the diameter of the central bore. In other embodiments, a protective member is positioned within a retaining member; wherein the protective member is configured as a helix and, as an instrument is inserted through the central bore of the helix, the helix expands, thereby increasing the diameter of the central bore.

Abstract: Trocar seal assemblies are disclosed which consist of a protective member and a retaining member. The protective member prevents accidental perforations of the retaining member during the insertion of an instrument through the seal assembly and assists in forming a seal against the instrument when inserted in the seal assembly. The protective member is generally configured with a circular upper portion and a generally conical lower portion. The lower portion of the protective member consists of a plurality of flaps which increasingly overlap as they progress to the lower portion of the conical shape, thereby forming a seal at the lowest portion where the flaps overlap entirely. The overlapping flaps expand with minimal resistance when instruments are inserted through the seal assembly, thereby ensuring a proper seal regardless of the size or configuration of the instrument.

Abstract: An externally threaded mandrel extends from one end of the inner tube of a pair of telescoping tubes and is staked thereto. A trifurcated collet threads on the mandrel whereby a conical exterior surface on the mandrel cooperates with a conical interior surface of the collet. Longitudinal ridges on the inner surface of the outer tube interlock with longitudinal grooves on the collet preventing relative motion between the outer tube and the collet while permitting longitudinal translation of the outer tube relative to the inner tube. Rotation of the inner tube in one direction advances the mandrel into the collet, with the interacting conical surfaces driving the furcate segments of the collet outward against the inner wall of the outer tube until a tight fit is produced. Friction between the collet and tube wall locks the tubes together. Reverse rotation of the inner tube withdraws the mandrel and releases the outer tube from the grip of the collet segments. The collet is made of a resilient plastic material.

Abstract: A positive cam lock for a pair of telescoping extension poles. The cam support is mounted to the inner pole and carries a coaxially rotatably mounted idler cam and an eccentrically rotatably mounted locking cam. The outer pole has a number of inwardly extending splines which engage corresponding grooves on the locking and idler cams. When the outer pole is rotated, the eccentric cam will rotate and lock the outer pole at a desired axial position with respect to the inner pole while the idler cam prevents misalignment. A key mounted to the locking cam rides in a keyway on the cam support for preventing over-rotation of the locking cam.