Abstract: A self-retracting step assembly is attached to a swimming platform provided on the rear of the hull of a boat. The self-retracting step assembly includes a ladder comprising a series of telescoping tubes which enable its extension and retraction. The step assembly including the ladder assembly are attached to the swimming platform in a position in which the ladder is capable of extending into the water wherein the watercraft or boat floats. The telescoping ladder assembly can be extended and placed from a normally horizontal position into an inclined position wherein at least the last step of the ladder reaches the water. The energy for extending the ladder is supplied by a human user. The step assembly includes a motor or mechanical means for storing the energy used for extending the ladder. The ladder assembly is locked into the extended and inclined position by an improved mechanism that is located within the assembly attached to the swimming platform.

Abstract: The trocar system includes a cannula insertable through a body wall using an obturator having a distal tip. A traction tread disposed interiorly of the obturator inverts at the distal tip and extends proximally along the outer surface of the obturator or cannula. At the distal tip the tread can facilitate parting rather than cutting the tissue. Along the outer surface, the tread can engage the tissue to pull it proximally along the advancing obturator. This produces counter forces which can result in a net proximal force facilitating distention of the abdominal wall and separation of the abdominal wall from internal organs. The traction tread can be axially and/or radially continuous. An associated method of operation includes the steps of contacting the body wall with the traction tread at the distal tip, and engaging the body wall with the traction tread along wall portions facing the outer surface.

Abstract: A pump comprising a housing, a diaphragm mounted in the housing, a pumping member or members, and a drive, preferably a wobble plate drive, for driving the pumping member or members on intake and discharge strokes. The wobble plate is preferably mounted on a ball bearing and includes a snap retainer assembly to retain the bearing in place without force fitting. The wobble plate preferably defines one or more open ended chambers in which the pumping member or members are placed. The annular zone or zones of the diaphragm which flex when driven by the wobble plate drive to provide the pumping action are configured to increase efficiency and/or to reduce wear.