Abstract: A retractable ladder assembly for marine applications having a frame and a ladder having a pair of channel members pivotally connected to the frame and extendible there from in a vertical position and in a horizontal position. A plurality of rung members extend between the channel members, and channel extension members are slidably supported in the channel members. A pair of strut connectors have one end pivotally connected to the frame and the other end pivotally connected to the lower ends of the channel extension members. A power actuator is supported by the frame to pivot the channel members between a vertical position and a horizontal position, the channel extension members extending from the upper ends of the channel members in the vertical position and are contained in the channel members in the horizontal position.

Abstract: The present invention provides a hydraulic actuator suitable for use in marine and other harsh environments. In the presently preferred embodiment, the hydraulic actuator includes a motor that is coupled to a pump assembly that is configured to displace hydraulic fluid. The hydraulic actuator also includes a cylinder bore that has an upper chamber and a lower chamber which are separated by a movable piston member. Pressure actuated valves are used to regulate the flow of high pressure hydraulic fluid to the cylinder bore. The pressure actuated valves are actuated in response to pressure generated by the pump assembly.

Abstract: A retractable ladder assembly for marine applications having a frame and a ladder having a pair of channel members pivotally connected to the frame and extendible there from in a vertical position and in a horizontal position. A plurality of rung members extend between the channel members, and channel extension members are slidably supported in the channel members. A pair of strut connectors have one end pivotally connected to the frame and the other end pivotally connected to the lower ends of the channel extension members. A power actuator is supported by the frame to pivot the channel members between a vertical position and a horizontal position, the channel extension members extending from the upper ends of the channel members in the vertical position and are contained in the channel members in the horizontal position.

Abstract: A hydraulic pump having a pump body formed by stacked plates mounted end-to-end. First and second ports for delivery and return of hydraulic fluid are formed through a port plate that is surmounted by a valve plate through which first and second main valve passages, each aligned with the first and second ports respectively, are formed. The valve plate is surmounted by a manifold plate in which first and second fluid distribution chambers, fluidly communicated with the first and second main valve passages respectively, are formed. A pump plate atop the manifold plate contains a gear assembly in a pumping chamber formed in the ends of the pump and manifold plates that draws fluid from one fluid distribution chamber and discharges it to the other.

Abstract: Disclosed is a system for controlling a numerically controlled machine tool sysem from a PC type computer system of the kind using an 8088 microprocessor chip and 8-bit words. The system includes an inverter timing board which is inserted into the PC equipment for conditioning signals from the parallel port of the computer into signals having wave forms of selected time length comforting to the numerical control tape code which is acceptable by the numerical control equipment at the machine tool.