A variable stroke high pressure pump is disclosed. The pump uses a wobble plate design with dynamically variable tilt to provide continuous adjustment of pump stroke length and output. Dynamically variable tilt is accomplished using a linearly actuated tilt thruster rotationally coupled to the drive shaft to maintain a selected tilt of the wobble plate through the rotation of the wobble plate.

A piston pump includes a first biasing mechanism configured to bias a swash plate in accordance with supplied control pressure, a second biasing mechanism configured to bias the swash plate against the first biasing mechanism, and a regulator configured to control the control pressure led to the first biasing mechanism in accordance with discharge pressure of the piston pump, wherein the second biasing mechanism has a pressure chamber to which the discharge pressure is led, and a control piston configured to be biased toward the swash plate by the discharge pressure led to the pressure chamber, and the regulator has a biasing member configured to bias the control piston toward the swash plate, and a control spool configured to be moved in accordance with biasing force of the biasing member, the control spool being configured to adjust fluid pressure.

A device and method for treating a wound of a patient with negative pressure is provided. The device comprises a heat-assisted pump system. The pump system can be powered in part by heat derived from the patient. The pump system may be configured to be highly planar, light weight, and portable. The pump system may comprise a Stirling engine or a thermal acoustic engine.

A variable stroke high pressure pump is disclosed. The pump uses a wobble plate design with dynamically variable tilt to provide continuous adjustment of pump stroke length and output. Dynamically variable tilt is accomplished using a linearly actuated tilt thruster rotationally coupled to the drive shaft to maintain a selected tilt of the wobble plate through the rotation of the wobble plate.

An opposed piston engine has a driveshaft with at least one combustion cylinder positioned between opposing, curvilinear shaped cams mounted on the driveshaft, where the center axis of the combustion cylinder is parallel with but spaced apart from the driveshaft axis. A piston assembly is disposed in each end of the cylinder, with one piston assembly engaging one cam and the other piston assembly engaging the other cam. Each piston assembly includes a cam follower that can move along a curvilinear shaped cam to reciprocate the piston assembly within the cylinder. The combustion cylinder includes an intake port in fluid communication with an annular intake channel formed in the engine block in which the cylinder is mounted, and an exhaust port in fluid communication with an annular exhaust channel formed in the engine block.

A device and method for treating a wound of a patient with negative pressure is provided. The device comprises a heat-assisted pump system. The pump system can be powered in part by heat derived from the patient. The pump system may be configured to be highly planar, light weight, and portable. The pump system may comprise a Stirling engine or a thermal acoustic engine.

A pump includes a pump body. The pump may also include a pump mounting flange configured to mount the pump to an engine flange including four clocked mounting holes. The pump mounting flange may include a first set of four mounting holes corresponding to the four clocked mounting holes in a first orientation. The pump mounting flange may include a second set of four mounting holes corresponding to the four clocked mounting holes in a second orientation.

A pump includes a pump body. The pump may also include a pump mounting flange configured to mount the pump to an engine flange including four clocked mounting holes. The pump mounting flange may include a first set of four mounting holes corresponding to the four clocked mounting holes in a first orientation. The pump mounting flange may include a second set of four mounting holes corresponding to the four clocked mounting holes in a second orientation.

A pump includes a cam plate, and an input shaft for rotationally driving the cam plate. A pump housing at least partially surrounds the cam plate and defines a cam plate oil reservoir around at least a portion of the cam plate. A bearing support is at least partially disposed within the cam plate oil reservoir. The bearing support defines a bearing oil reservoir at least partially surrounding a portion of the input shaft. At least one passage extends between the bearing oil reservoir and the cam plate oil reservoir. Dynamic motion imparted on oil within the cam plate oil reservoir facilitates migration of oil from the cam plate oil reservoir through a bearing at least partially supported by the bearing support into the bearing oil reservoir and through the at least one passage into the cam plate oil reservoir.

A variable stroke high pressure pump is disclosed. The pump uses a wobble plate design with dynamically variable tilt to provide continuous adjustment of pump stroke length and output. Dynamically variable tilt is accomplished using a linearly actuated tilt thruster rotationally coupled to the drive shaft to maintain a selected tilt of the wobble plate through the rotation of the wobble plate.