Abstract: A shaft arrangement for an axial piston pump assembly to couple to a rotatable member such as a gear therewith. A shaft extends at least partially through a housing chamber of the pump about a longitudinal axis. Reciprocating pistons are disposed within the chamber radially about the shaft. A cam unit is fitted over the shaft and provides an angled camming surface to engage the pistons. Bearing assemblies are fitted over the cam unit. An adapter can be fitted over the proximal end of the cam unit. The adapter has a distal surface which may abut the bearing assembly and be axially spaced from the cam unit, and an outer radial surface to engage the rotatable member. A clamping device provides a desired clamp load path between the rotatable member, the adapter, the cam unit, the bearing assemblies and the shaft.

Abstract: A shaft arrangement for an axial piston pump assembly to couple to a rotatable member such as a gear therewith. A shaft extends at least partially through a housing chamber of the pump about a longitudinal axis. Reciprocating pistons are disposed within the chamber radially about the shaft. A cam unit is fitted over the shaft and provides an angled camming surface to engage the pistons. Bearing assemblies are fitted over the cam unit. An adapter can be fitted over the proximal end of the cam unit. The adapter has a distal surface which may abut the bearing assembly and be axially spaced from the cam unit, and an outer radial surface to engage the rotatable member. A clamping device provides a desired clamp load path between the rotatable member, the adapter, the cam unit, the bearing assemblies and the shaft.

Abstract: A hydraulic system, such as a fuel injection system, includes a fixed displacement pump with at least one pump piston. A sleeve surrounds each pump piston and provides the method by which fluid displaced by the pumping stroke of the pump piston is directed either to a high pressure area in the pump or a low pressure area. The sleeves are a portion of an electro-hydraulic controller that includes a mechanical bias to bias the pump to a high output position when a pressure differential between the outlet area and the inlet area is relatively low, such as at cold start up. This aspect facilitates priming of the system. In addition, the controller includes a biasing hydraulic surface in opposition to the mechanical biaser that serves to bias the pump to its low output position when the pressure differential between the outlet area and the inlet area is relatively high. This aspect prevents over pressurization in the event that electric current to the controller is disrupted.

Abstract: A hydraulic system, such as a fuel injection system, includes a fixed displacement pump with at least one pump piston. A sleeve surrounds each pump piston and provides the method by which fluid displaced by the pumping stroke of the pump piston is directed either to a high pressure area in the pump or a low pressure area. The sleeves are a portion of an electro-hydraulic controller that includes a mechanical bias to bias the pump to a high output position when a pressure differential between the outlet area and the inlet area is relatively low, such as at cold start up. This aspect facilitates priming of the system. In addition, the controller includes a biasing hydraulic surface in opposition to the mechanical biaser that serves to bias the pump to its low output position when the pressure differential between the outlet area and the inlet area is relatively high. This aspect prevents over pressurization in the event that electric current to the controller is disrupted.

Abstract: A hydraulically-actuated system includes a fixed displacement pump with at least one piston that reciprocates in a pump housing that defines a high pressure area and a low pressure area. A control valve is attached to the pump housing and moveable between a first position in which the piston displaces fluid in a first proportion between the high pressure area and the low pressure area, and a second position in which the piston displaces fluid in a second proportion between the high pressure area and the low pressure area. At least one hydraulically-actuated device is connected to the high pressure area of the pump. A source of low pressure fluid is connected to the low pressure area of the pump. An electronic control module is in communication with and capable of controlling the position of the control valve.