A compressor comprises a first cylinder for compressing a fluid and a second cylinder for driving a piston in the first cylinder. The first cylinder comprises a chamber with first and second ends. The piston is reciprocally movable along an axial direction of the chamber for compressing a fluid. Three or more first ports at the first end include at least one first inlet port and at least one first outlet port. Three or more second ports at the second end include at least one second inlet port and at least one second outlet port. Each port has an axial direction parallel to the axial direction of the chamber. A check valve is connected inline with each port along the axial direction of the port.

A compressor comprises a first cylinder for compressing a fluid and a second cylinder for driving a piston in the first cylinder. The first cylinder comprises a chamber configured to receive the fluid. The piston is reciprocally movable in the chamber for compressing the fluid. The chamber comprises four ports at the first end including two inlet ports and two outlet ports with a check valve is connected to each port. Each of the four ports is slanted such that the plurality of check valves and inlet and outlet conduits are spaced apart from the second cylinder. The compressor further comprises an inlet conduit to supply the fluid from a fluid source to the chamber through the inlet ports and an outlet conduit for receiving fluid from the chamber through the outlet ports.

A compressor comprises a first cylinder for compressing a fluid and a second cylinder for driving a piston in the first cylinder. The first cylinder comprises a chamber configured to receive the fluid. The piston is reciprocally movable in the chamber for compressing the fluid. The chamber comprises four ports at the first end including two inlet ports and two outlet ports with a check valve is connected to each port. Each of the four ports is slanted such that the plurality of check valves and inlet and outlet conduits are spaced apart from the second cylinder. The compressor further comprises an inlet conduit to supply the fluid from a fluid source to the chamber through the inlet ports and an outlet conduit for receiving fluid from the chamber through the outlet ports.

An axial piston machine has a swash plate and an adjusting device having an adjusting cylinder and a double-acting adjusting piston which is longitudinally movable in the adjusting cylinder and includes a piston and a piston rod, which is fixedly connected to the piston and is articulated to the swash plate. The joint between the adjusting piston and the swash plate is a movable swivel joint having a joint body receptacle on one part and a joint body on the other part of the adjusting piston and the swash plate. The joint body is closely guided in the joint body receptacle in the direction of movement of the adjusting piston, is rotatable about an axis of rotation running parallel to the pivot axis of the swashplate, and is movable with a directional component perpendicular to the direction of movement of the adjusting piston and perpendicular to the axis of rotation.

An axial piston machine has a swash plate and an adjusting device having an adjusting cylinder and a double-acting adjusting piston which is longitudinally movable in the adjusting cylinder and includes a piston and a piston rod, which is fixedly connected to the piston and is articulated to the swash plate. The joint between the adjusting piston and the swash plate is a movable swivel joint having a joint body receptacle on one part and a joint body on the other part of the adjusting piston and the swash plate. The joint body is closely guided in the joint body receptacle in the direction of movement of the adjusting piston, is rotatable about an axis of rotation running parallel to the pivot axis of the swashplate, and is movable with a directional component perpendicular to the direction of movement of the adjusting piston and perpendicular to the axis of rotation.

A piston (8) is provided in a motor main body (4). A first motor chamber (9) is provided above the piston (8) and a second motor chamber (10) is provided below the piston (8). A pilot valve element (18) is provided so as to protrude from the piston (8). When a supply/discharge valve (13) is moved to its upper limit position or its lower limit position by the movement of the pilot valve element (18) in an up-down direction, a first valve member (25) of the supply/discharge valve (13) switches between supplying and discharging pressure fluid to and from the first motor chamber (9) and a second valve member (26) of the supply/discharge w valve (13) switches between supplying and discharging pressure fluid to and from the second motor chamber (10).

A linear pump includes a centrally-disposed drive system and a plunger having a center portion coupled to the drive system, and first and second fluid ends disposed at the first and second ends of the plunger. The pump further includes first and second packing seals each being disposed about the plunger to isolate fluids within the respective first and second fluid ends. First and second adapters are disposed at an interface between the drive system and respective first and second fluid ends, each adapter incorporating an angled deflector configured to deflect and redirect high-pressure fluids escaping past the respective packing seal toward the drive system.

A closed loop, self-priming hydraulic system comprising a reciprocating, hydraulic piston pump, a high pressure loop and a low pressure loop is disclosed. The reciprocating, hydraulic piston pump comprises a first piston operating in a first piston bore and a second piston operating in a second piston bore. The high pressure loop is defined by a high pressure accumulator that is fluidly connected to an inlet of the first piston bore and an outlet of the second piston bore. The low pressure loop is defined by a low pressure accumulator that is fluidly connected to an inlet of the second piston bore and an outlet of the first piston bore. The closed-loop, self-priming hydraulic system manipulates a hydraulic fluid to convert energy from one form to another.

A closed loop, self-priming hydraulic system comprising a reciprocating, hydraulic piston pump, a high pressure loop and a low pressure loop is disclosed. The reciprocating, hydraulic piston pump comprises a first piston operating in a first piston bore and a second piston operating in a second piston bore. The high pressure loop is defined by a high pressure accumulator that is fluidly connected to an inlet of the first piston bore and an outlet of the second piston bore. The low pressure loop is defined by a low pressure accumulator that is fluidly connected to an inlet of the second piston bore and an outlet of the first piston bore. The closed-loop, self-priming hydraulic system manipulates a hydraulic fluid to convert energy from one form to another.

A pump system is disclosed. The pump system includes a cavity (102) comprising one or more inlet check valves (120, 122) and one or more outlet check valves (124, 126). A piston (104) having an enlargement (106) at a substantially middle portion of the piston (104). The piston (104) is capable of moving within the cavity (102) for forming a first chamber (116) and a second chamber (118), wherein up movement of the piston (104) the volume in the first chamber (112) is increased and simultaneously the volume in the second chamber (118) is decreased and vice versa.