A method for operating a hydraulic consumer on an electrically actuated control valve includes providing the valve with an open valve position for establishing a connection between a valve inlet and a pilot line for influencing a pivot angle set on an axial piston pump and a system pressure which is present at the valve inlet and dependent on the pivot angle. Data regarding the current system pressure and the current pivot angle are detected and communicated to a control unit. The method includes determining an incorrect setting of the control valve if the control unit detects that a delivery volume flow of the axial piston pump is smaller than a value to be expected based on valve position, or the control unit detects that the system pressure present at the valve inlet is at a maximum without a delivery volume flow flowing in the direction of the hydraulic consumer.

A method for operating a hydraulic consumer on an electrically actuated control valve includes providing the valve with an open valve position for establishing a connection between a valve inlet and a pilot line for influencing a pivot angle set on an axial piston pump and a system pressure which is present at the valve inlet and dependent on the pivot angle. Data regarding the current system pressure and the current pivot angle are detected and communicated to a control unit. The method includes determining an incorrect setting of the control valve if the control unit detects that a delivery volume flow of the axial piston pump is smaller than a value to be expected based on valve position, or the control unit detects that the system pressure present at the valve inlet is at a maximum without a delivery volume flow flowing in the direction of the hydraulic consumer.

A pumping system includes a first variable displacement pump having a first inlet and a first outlet. The first outlet is fluidically connected to a system outlet. A first actuator is mechanically coupled to a first displacement mechanism of the first variable displacement pump A second variable displacement pump includes a second inlet and a second outlet. The second outlet is fluidically connected to the system outlet. The pumping system also includes a second actuator mechanically coupled to a second displacement mechanism of the second variable displacement pump. An electrohydraulic servo valve is hydraulically connected to the first and second actuators. An electronic engine controller is in communication with the electrohydraulic servo valve and is configured to send electrical current to the electrohydraulic servo valve to drive the first actuator and the second actuator.

A pumping system includes a first variable displacement pump having a first inlet and a first outlet. The first outlet is fluidically connected to a system outlet. A first actuator is mechanically coupled to a first displacement mechanism of the first variable displacement pump A second variable displacement pump includes a second inlet and a second outlet. The second outlet is fluidically connected to the system outlet. The pumping system also includes a second actuator mechanically coupled to a second displacement mechanism of the second variable displacement pump. An electrohydraulic servo valve is hydraulically connected to the first and second actuators. An electronic engine controller is in communication with the electrohydraulic servo valve and is configured to send electrical current to the electrohydraulic servo valve to drive the first actuator and the second actuator.

A compressor including: a casing; a rotary shaft rotatably mounted in the casing; a compression mechanism configured to compress a refrigerant by operating in conjunction with the rotary shaft; a thrust plate configured to support an end surface of the rotary shaft; a chamber configured to accommodate the thrust plate; and a slit configured to guide oil to the chamber, in which a part of the slit is formed to face a contact portion between the rotary shaft and the thrust plate, such that it is possible to supply the oil between the rotary shaft and the thrust plate, thereby preventing damage to the thrust plate for supporting the rotary shaft. In addition, an inner diameter of the chamber gradually increases, and the chamber extends to an end surface of a cylinder block, such that the cylinder block may be easily extracted from a mold.

A compressor including: a casing; a rotary shaft rotatably mounted in the casing; a compression mechanism configured to compress a refrigerant by operating in conjunction with the rotary shaft; a thrust plate configured to support an end surface of the rotary shaft; a chamber configured to accommodate the thrust plate; and a slit configured to guide oil to the chamber, in which a part of the slit is formed to face a contact portion between the rotary shaft and the thrust plate, such that it is possible to supply the oil between the rotary shaft and the thrust plate, thereby preventing damage to the thrust plate for supporting the rotary shaft. In addition, an inner diameter of the chamber gradually increases, and the chamber extends to an end surface of a cylinder block, such that the cylinder block may be easily extracted from a mold.

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 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.

Control systems and feedback assemblies for hydraulic axial displacement machines, such as pumps and motors. The control systems and feedback assemblies can reduce friction on the charging spools and provide for a more reliable return of the swashplate to a neutral position. Aspects of the control systems and feedback assemblies can be modularized for, e.g., easy maintenance and to reduce the overall size of the system.

A hydraulic system includes: a cylinder that moves a moving object in a vertical direction by extension and retraction of a rod; a first bidirectional pump connected to a head-side chamber of the cylinder by a first supply/discharge line; a second bidirectional pump connected to a rod-side chamber of the cylinder by a second supply/discharge line and coupled to the first bidirectional pump in a manner enabling torque to be transmitted between the first and second bidirectional pumps; a relay line connecting the first and second bidirectional pumps such that a hydraulic liquid discharged from one of the first and second bidirectional pumps is introduced into the other of the first and second bidirectional pumps; and a servomotor that drives the first or second bidirectional pump. At least one of the first and second bidirectional pumps is a variable displacement pump whose delivery capacity per rotation is freely variable.