There is provided a hydraulic drive device for a working machine with which a number of times of maintenance can be reduced. A controller (20) opens a first on-off valve (25a), closes a second on-off valve (25b), switches a first directional switching valve (30a) to a first position (A), and switches a second directional switching valve (30b) to a third position (C), thereby pressure oil from a hydraulic pump (1a) is supplied from the first on-off valve to an actuator (5a) through the first directional switching valve. When history data of the first on-off valve is determined to satisfy a prescribed condition, the controller closes the first on-off valve, opens the second on-off valve, switches the first directional switching valve to a second position (B), and switches the second directional switching valve to a fourth position (D), thereby pressure oil from the hydraulic pump is supplied from the second on-off valve to the actuator through the second directional switching valve. For example, the controller determines that the prescribed condition is satisfied when an operation number of times of the first on-off valve reaches a first prescribed value.

The present disclosure discloses a hydraulic machine including a support assembly and a main cylinder device connected with the support assembly. The main cylinder device includes at least two main cylinder assemblies and at least two piston rods respectively. The at least two piston rods are opposite to each other and move along opposite directions and on the same straight line. A support worktable device is disposed on the support assembly and spaced with the main cylinder device. At least two pressing mechanisms are formed between the support worktable device and the at least two main cylinder assemblies or between the support worktable device and the at least two piston rods. The at least two pressing mechanisms are configured for pressing work pieces simultaneously.

There is provided a hydraulic drive device for a working machine with which a number of times of maintenance can be reduced. A controller (20) opens a first on-off valve (25a), closes a second on-off valve (25b), switches a first directional switching valve (30a) to a first position (A), and switches a second directional switching valve (30b) to a third position (C), thereby pressure oil from a hydraulic pump (1a) is supplied from the first on-off valve to an actuator (5a) through the first directional switching valve. When history data of the first on-off valve is determined to satisfy a prescribed condition, the controller closes the first on-off valve, opens the second on-off valve, switches the first directional switching valve to a second position (B), and switches the second directional switching valve to a fourth position (D), thereby pressure oil from the hydraulic pump is supplied from the second on-off valve to the actuator through the second directional switching valve. For example, the controller determines that the prescribed condition is satisfied when an operation number of times of the first on-off valve reaches a first prescribed value.

A stabilizing system includes a plurality of jacks, each operated by a corresponding hydraulic actuator. A hydraulic fluid transfer pump supplies hydraulic fluid to and receives hydraulic fluid from one or more pressure chambers of the actuator. A pilot-operated check or directional valve may be provided in fluid communication with one or more of the pressure chambers and configured to regulate the flow of hydraulic fluid to and from the pressure chamber. A directional control valve may connect the pump output with the jacks via respective pilot-operated directional valves. The directional control valve may include a plurality of switch positions respectively connecting the pump output with pairs of the jacks.

A method and system for the hydraulic control of a concrete placing boom (14) comprising a plurality of boom arms (16), wherein hydraulic drive cylinders (18) for the boom arms (16), which are connected to one another in an articulated manner, are controlled by a hydraulic circuit (34), wherein a supply pressure is supplied via a hydraulic pump (32) to the hydraulic circuit (34), and wherein a pressure signal is captured in the drive cylinders (18) by at least one pressure sensor (38) for each cylinder. The maximum pressure in the drive cylinders (18) is determined from the pressure signals and the supply pressure is adjusted by an electronic control unit (36) according to the maximum pressure.

A robotic joint that includes a hydraulic actuator. The hydraulic actuator includes a hollow tube that has a first opening at a first end of the hollow tube and that has a second opening at a second end of the hollow tube. The hollow tube contains hydraulic fluid. A moveable magnet moves within hollow tube as a result of a magnetic field within the hollow tube. A magnetic field source located outside the hollow tube creates the magnetic field within the hollow tube. When the moveable magnet moves to the first end of the hollow tube, a first piston pushes hydraulic fluid out of the first opening. When the moveable magnet moves to the second end of the hollow tube a second piston pushes hydraulic fluid out of the second opening.

An actuator comprising: a piezo actuator; a drive having a drive chamber and a drive piston element driven by the piezo actuator; a first output having an output chamber and a piston element; and a second output having an output chamber and a piston element. At least part of the hydraulic fluid is conveyed out of the drive chamber by movement of the drive piston element and into the first output chamber. At least part of the hydraulic fluid is conveyed out of the drive chamber and into the second output chamber. The second output piston element has a hydraulically active second output face which is different in size from the first output face. There may be a coupling device mechanically coupling the first output piston element to the second output piston element.

An energy generating system that utilizes a movement of a fluid/gas includes a plurality of floor tiles, a fluid/gas, and a power generating unit. Preferably, the plurality of floor tiles is layered across an area with high foot traffic. The fluid/gas is confined in a fluid tank positioned underneath the plurality of floor tiles such that a pressure applied on the plurality of floor tiles is transferred onto the fluid/gas, and generates movement in the fluid/gas. The movement allows the fluid/gas to flow towards a plurality of turbines of the power generating unit through a piping network and a plenum passage, and rotate the plurality of turbines. The rotational movement of the turbines is converted into electrical energy by a generator of the power generating unit. The electrical output of the generator is stored in a battery bank.

A multi-buffer energy accumulation apparatus comprises: an energy storage cylinder, an oil tank, a first scroll spring mechanism, a second scroll spring mechanism, a hydraulic motor, differential planetary train of gearings, and a generator; wherein the energy storage cylinder comprises a hermetically sealed cylinder body, one end of the hermetically sealed cylinder body being provided with an elastic mobile device, the other end thereof being provided with an energy transmission device, and hydraulic oil is filled in the hermetically sealed cylinder body between the elastic mobile device and the energy transmission device; the hermetically sealed cylinder body, the hydraulic motor, and the oil tank are connected via an oil circuit to form a hydraulic loop; the energy transmission device is connected with the first scroll mechanism; the hydraulic motor is connected with the second scroll spring mechanism.

A hydraulic pressure generating device includes a base body having a master cylinder configured to generate a brake hydraulic pressure and a slave cylinder configured to generate a brake hydraulic pressure. The base body is provided with a motor configured as a driving source for the slave cylinder and a control device configured to control the motor. A motor shaft of the motor, a cylinder axis of the master cylinder, and a cylinder axis of the slave cylinder are disposed in parallel with each other. Then a virtual plane including the cylinder axis of the master cylinder is set as a reference plane, a housing of the control device is disposed on one side of the reference plane and the motor is disposed on the other side of the reference plane.