A hydraulic engine with hydraulic pumps that moves the oil filled in the body thereof through the hydraulic pumps to allow rotational load bodies to be driven by means of the reciprocation of pistons, thereby obtaining a rotational force required for driving, includes: a power supply adapted to supply power to a driving part and to charge the power generated from rotational load bodies through the driving of a power driving part; the driving part driven through the power supplied from the power supply; a pair of hydraulic pumps adapted to pump a fluid through the rotation of the driving part; and the power driving part adapted to generate a driving force through the reciprocation of a driving piston.

An axial piston machine may include a housing, a guide, a shaft, at least two cylinders each delimited by an associated cylinder wall, at least two pistons, a feed configured to supply a working fluid, an exhaust configured to discharge the working fluid, and at least one actuator configured to open and close a plurality of secondary outlets. Each associated cylinder wall may include a primary outlet and a secondary outlet of the plurality of secondary outlets. Each primary outlet and each secondary outlet may be fluidically connected to an outlet chamber that is fluidically connected to the exhaust. Each primary outlet may open into an associated primary outlet channel that opens into the outlet chamber. Each secondary outlet may be fluidically connected to an associated secondary outlet channel that opens into the outlet chamber and is separate from the plurality of primary outlet channels.

A variable displacement pump-motor includes a pump-motor having a plurality of cylinders and pistons, and further including a main shaft rotatable relative to the system body. A hydro mechanical control system includes a plurality of main stage valves in communication with the plurality of cylinders. Each of the main stage valves is configured to open and close a cylinder of the plurality of cylinders to one or more of high or low pressure fluid sources. A pilot spool valve is in selective communication with each of the main stage valves. The pilot spool rotates with the main shaft. The pilot spool includes coding configured to operate each of the main stage valves to open and close the respective cylinders to the one or more high and low pressure fluid sources according to a translational position of the pilot spool and rotation of the pilot spool by the main shaft.

A low-energy and high pressure, hydraulic, pneumatic engine contains: a casing device, two main-cylinder devices, a holder device, two main-crankshaft devices, two recycle-valve devices, two swing-arm devices, two movable-valve devices, two recycle-cylinder devices, two recycle-crankshaft devices, and two umbrella-shaped gear devices. The engine operates without using gasoline or diesel, thus avoiding discharge of harmful substance or gas and pollution. The high pressure gas forces the hydraulic oil without using gasoline or diesel so as to start the engine, and the hydraulic oil recycles and reuses repeatedly, thus obtaining environmental protection. And the high pressure gas forces the hydraulic oil so as to circulate the hydraulic oil, and the communication of the low-energy and high pressure and the low pressure matches with the circulation space of the fluid operation to produce the torque, hence four strokes cycle of intake, compression, combustion and exhaust are not required.

The crankless sinusoidal engine has at least one cylinder, one standard piston and head with combustion chamber and inlet and exhaust valves. A main shaft with one flywheel with incorporated sinusoidal track, Connection between the piston and the sinusoidal track consists of four items; to wit, one connecting rod, one bearing trolley and two segmented rollers, said rollers being in constant contact with said sinusoidal track, one bearing on each side thereof. The bearing trolley sliding on guide pins anchored in opposite ends of cast (alternatively fabricated) housing, said guide pins positioned parallel to the main shaft.

Pressure from the piston forces the segmented rollers against the sinusoidal track, causing rotation.

An axial piston machine may include a housing, a guide, a shaft, at least two cylinders each delimited by an associated cylinder wall, at least two pistons, a feed configured to supply a working fluid, an exhaust configured to discharge the working fluid, and at least one actuator configured to open and close a plurality of secondary outlets. Each associated cylinder wall may include a primary outlet and a secondary outlet of the plurality of secondary outlets. Each primary outlet and each secondary outlet may be fluidically connected to an outlet chamber that is fluidically connected to the exhaust. Each primary outlet may open into an associated primary outlet channel that opens into the outlet chamber. Each secondary outlet may be fluidically connected to an associated secondary outlet channel that opens into the outlet chamber and is separate from the plurality of primary outlet channels.

A low-energy and high pressure, hydraulic, pneumatic engine contains: a casing device, two main-cylinder devices, a holder device, two main-crankshaft devices, two recycle-valve devices, two swing-arm devices, two movable-valve devices, two recycle-cylinder devices, two recycle-crankshaft devices, and two umbrella-shaped gear devices. The engine operates without using gasoline or diesel, thus avoiding discharge of harmful substance or gas and pollution. The high pressure gas forces the hydraulic oil without using gasoline or diesel so as to start the engine, and the hydraulic oil recycles and reuses repeatedly, thus obtaining environmental protection. And the high pressure gas forces the hydraulic oil so as to circulate the hydraulic oil, and the communication of the low-energy and high pressure and the low pressure matches with the circulation space of the fluid operation to produce the torque, hence four strokes cycle of intake, compression, combustion and exhaust are not required.

A variable displacement pump-motor includes a pump-motor having a plurality of cylinders and pistons, and further including a main shaft rotatable relative to the system body. A hydro mechanical control system includes a plurality of main stage valves in communication with the plurality of cylinders. Each of the main stage valves is configured to open and close a cylinder of the plurality of cylinders to one or more of high or low pressure fluid sources. A pilot spool valve is in selective communication with each of the main stage valves. The pilot spool rotates with the main shaft. The pilot spool includes coding configured to operate each of the main stage valves to open and close the respective cylinders to the one or more high and low pressure fluid sources according to a translational position of the pilot spool and rotation of the pilot spool by the main shaft.