The present invention relates to an apparatus and method for controlling a construction machine. An apparatus for controlling a construction machine according to an embodiment of the present invention may compare a fuel efficiency gain expected when engine revolutions per minute (RPM) is decreased with a fuel efficiency gain expected when a current torque curve is changed to a torque curve corresponding to a condition in which auxiliary power is provided and selected from among the plurality of torque curves and then the latter torque curve is selectively applied, based on the fuel efficiency map, and may control an engine by means of a method by which a larger fuel efficiency gain is expected.

The present invention relates to a system comprising: a shaft having a distal end and a proximal end; a casing defining a housing in which a hydraulic device is rotatably mounted on the shaft; and a sealing element comprising a low pressure dynamic sealing means and a reinforced dynamic sealing means formed by a static seal tightly mounted on a friction pad, such as to isolate the dynamic sealing means from the rotating hydraulic device, said sealing element defining a discharge chamber between the dynamic sealing means and the reinforced dynamic sealing means, which discharge chamber is connected to a drain via a pipe arranged on the surface of the shaft, between the hydraulic device and the shaft, so as to discharge the fluid located in the discharge chamber, such that said discharge chamber is not subjected to the pressure in the casing of the hydraulic device.

The invention provides a device and method for converting reciprocating motion of various amplitudes and frequencies into unidirectional fluid flow, comprising a piston section and a valves section. The unidirectional fluid flow may then be used for various processes including for example conversion to mechanical or electrical power.

Hydrostatic adjusting device of a hydraulic machine, the swept volume of which can be adjusted by way of a servo adjusting unit, having a control unit which has a control cylinder which has at least one inlet for pressurized hydraulic fluid, at least one servo connector for a connecting line to the servo adjusting unit, and at least one outlet to a hydraulic fluid collecting region. A control piston is arranged in the control cylinder, which control piston can be displaced by means of at least one control piston actuator and has control edges. In interaction with control edges which are configured in the control cylinder, the inlet or the outlet can be alternately connected hydraulically to the connecting line, whereby the pressure which prevails in the connecting line can be returned hydraulically via a control line to at least one end side of the control piston.

A hydrostatic system includes a hydraulic system and at least one sensor configured to monitor a parameter of the hydraulic system, the at least one sensor including a wireless transmitter configured to generate wireless transmissions based on the parameter. The hydrostatic system further includes an electronic control box including a wireless receiver that is configured to receive the wireless transmissions generated by the at least one sensor. The electronic control box is configured to control the hydraulic system based at least in part on the received wireless transmissions.

A hydraulic apparatus comprising a casing (1) having arranged therein a hydraulic machine (2), a shaft (4) mounted to rotate relative to the casing (1) by means of a bearing (5), a braking system (3) having a plurality of brake disks (31, 34) configured to prevent the shaft (4) rotating relative to the casing (1) in selective manner, and a control system (6, 7) for controlling said braking disks (31, 34), the hydraulic system including an irrigation system adapted to cool said brake disks (31, 34) by means of a fluid, the irrigation system including a fluid inlet (81) and a fluid outlet (82), the hydraulic system being characterized in that the fluid inlet and outlet (81, 82) of the irrigation system define a fluid flow within the casing in which the braking system (3) is downstream from the hydraulic machine (2).

Methods and systems for a hydraulic axial piston motor with a braking system are described. A brake assembly for a hydraulic axial piston motor, comprising: a cylinder block and a pair of braking pads positioned around the cylinder block, wherein compression of the braking pads against an outer surface of the cylinder block realizes braking of the cylinder block.

An opposed swash plate type fluid pressure rotating machine in which a first piston and a second piston projecting from opposite ends of a cylinder block reciprocate in a cylinder, respectively following a first swash plate and a second swash plate includes a center spring for biasing the cylinder block toward the second swash plate. A housing hole (biasing force receiving part) for receiving a biasing force of the center spring is formed on one end part of the cylinder block. The tip of a second neck (reaction force receiving part) for receiving a reaction force from the second swash plate is formed on the other end part of the cylinder block. The cylinder block is biased only toward the second swash plate by the center spring.

A method and apparatus for gas compression and expansion that simultaneously serves as storage tank for the compressed gas, and heat exchanger for heat transfer to the environment to maintain near-isothermal conditions.

A method is provided for controlling a hydraulic cylinder in a work machine, which hydraulic cylinder is arranged to move an implement that is subjected to a load, with the hydraulic cylinder being controlled by a hydraulic machine. The method includes detecting that a lifting movement of the implement is to be initiated, and attaining a basic speed of the hydraulic machine before lifting takes place.