Abstract: The present disclosure provides a pilot proportional control valve apparatus, an automatic calibration method, engineering machinery and a storage medium, and relates to the technical field of engineering machinery, wherein the pilot proportional control valve apparatus including a hydraulic system and a controller; the hydraulic system including: a plurality of proportional pressure reducing valves, a calibration reversing valve, and a pressure sensor; the calibration reversing valve including a plurality of reversing units, an output end of each proportional pressure reducing valve being respectively connected with an input end of one corresponding reversing unit; the pressure sensor being arranged in a detection oil path; the controller performing calibration processing on the proportional pressure reducing valve according to a pilot oil detection pressure and an output pressure value of the proportional pressure reducing valve.

Abstract: The disclosure concerns an electronic control unit for a hydraulic system, the hydraulic system comprising a pump drivingly coupled to a motor, the pump configured to provide a supply pressure in a supply line of the hydraulic system. The electronic control unit is configured to receive a load sensing signal corresponding to a sensed load measure of the hydraulic system; determine, based on the load sensing signal and a predetermined pump margin, a target torque parameter for the motor; and adjust the motor based on the target torque parameter. The disclosure further concerns a hydraulic system and a method for controlling a hydraulic system.

Abstract: A piston for an internal combustion engine, said piston having an upper piston portion (1) in which a ring zone (2) is located, and a piston lower part (3) having two opposing, load-carrying skirt wall sections (4,5) on the pressure- and counter-pressure sides of the piston adjoins the upper piston portion (1), and the two load-carrying skirt wall sections (4,5) are interconnected via connecting walls (6,7) that are recessed relative to the outer diameter of the piston. Each connecting wall (6, 7) includes a pin bore having a pin bore axis (18) for receiving a pin. The two opposing, load-carrying wall sections (4, 5) have different wall thicknesses and different transition regions at the transition of their lateral skirt connections (8,9 and 16,17) to the recessed connection walls (6,7).

Abstract: A handle includes a limiting member, a handle body, a switch member and a biasing member. The limiting member is adapted to connect with an air pump and has a limiting recess. The handle body is pivotally connected to the limiting member to change between a folded position and a use position, and has a slot. The switch member is pivotally arranged in the slot and has a restricting portion detachably engaged with the limiting recess. The restricting portion is engaged with the limiting recess when the handle body is in the use position, and is disengaged from the limiting recess as the switch member moved relative to the slot. The biasing member biases the switch member toward the outside of the slot.

Abstract: A torque converter includes a front cover arranged to receive a torque and an impeller having an impeller shell connected to the front cover. The torque converter further includes a turbine in fluid communication with the impeller and including a turbine shell. The torque converter further includes a lock-up clutch including a clutch plate that is non-rotatably connected to the turbine shell.

Abstract: A power production system is provided that includes: a hydraulic turbine, installable in a penstock and being rotatable in a first rotation direction by effect of a flow of fluid flowing in the penstock in a downward direction; an energy converter group; an accumulator; a control unit, configured to operate the system in a power generation mode, in which the energy converter group receives an input mechanical power from the hydraulic turbine rotating in the first rotation direction, generates an output electric power and supplies said output electrical power to an external grid and/or to the accumulator, and in a downward pushing mode, in which the energy converter group absorbs an input electrical power from the accumulator and generates an output mechanical power to move the hydraulic turbine.

Abstract: A device for holding a hydraulic cylinder stem in position includes a hydraulic block having series-connected primary and secondary check valves. The latter includes a secondary control stem having a secondary valve body and a seal. A first throttle upstream and a second throttle downstream are closed in a secondary control stem closed position where the seal tightly blocks the secondary check valve, each throttle having a tiny throttle closing gap, preferably 0.1 mm or less. The control stem can move axially into an intermediate position where the throttles remain closed, that is, have a tiny closing gap, but valve body and seal are lifted from a secondary valve seat. The control stem can be moved further into an opening position where the throttles are open, each having an opening gap much larger than the closing gap, and the valve body and seal are lifted from the valve seat.

Abstract: The disclosed embodiments relates an arrangement for tilting or turning a tool, the arrangement including at least one actuator for tilting and turning the tool, the actuator including at least a frame part adapted to be closed by a cover, the frame part and the cover enclosing a chamber portion (8) where a blade part having one or more blade gaskets is provided to divide the chamber portion into separate chamber spaces, the blade part being connected, at its first end, to a shaft, the second end of the blade part being adapted move reciprocally in the chamber portion, rotating the shaft at the same time. The joint between the frame part and the cover is sealed by a gasket contacting the blade gaskets.

Abstract: A control device and method for controlling a disengaging actuator (1) of a tool attachment, the device comprising a three-state switch (2), with a middle neutral position (20), a first end position (21), and a second end position (22), a control unit (3, 3?), having an input corresponding to an activation of the first end position (21), an electro-valve (4) coupled hydraulically to the disengaging actuator (1), having a coil (40), a first control line (41) and a second control line (42) coupled respectively to first and second terminals of the coil (40) of the electro-valve, wherein one of the first and second control lines is coupled to the second end position (22) of the three-state switch and the other of the first and second control lines is coupled to an output of the control unit, such that both control lines have to be activated to allow disengagement.

Abstract: A hydraulic system includes: a high-pressure line; a pump configured to supply pressurized hydraulic fluid to the high-pressure line; a variable displacement hydraulic machine connected by a fluid connection to the high-pressure line for rotationally driving the rotatable load; an electronic control unit; an energy storing device connected to the high-pressure line and configured to communicate with the high-pressure line by receiving energy from the high-pressure line and/or supplying energy to the high-pressure line; and a first detector configured to detect the amount of energy stored in the energy storing device and to transmit a signal indicating said amount of energy stored to the electronic control unit. The electronic control unit is configured to control the volume flow intake of the variable displacement hydraulic machine dependent on a target output of the variable displacement hydraulic machine and on the detected amount of energy stored in the energy storing device.

Abstract: Disclosed herein are various embodiments of a hydraulic actuator that includes one or more check valves having a dynamically varying cracking pressure. In certain embodiments, a hydraulic actuator may be configured to vary the cracking pressure of a check valve based on an operating condition of a pump of the hydraulic actuator. The check valve may be located along a bypass path in the hydraulic actuator, thereby allowing for fluid flow to bypass a pump of the hydraulic actuator by passing through the check valve. The use of such hydraulic actuators is contemplated in, for example, an active suspension system of a vehicle. Additionally, various embodiments of suitable check valves are disclosed. Additionally, methods are disclosed for operation of the check valve and the hydraulic actuator.

Abstract: Disclosed are seal arrangements in a hydraulic device. The seal arrangement includes a seal channel defining a loop. A seal is seated within the seal channel. A coolant flow passage has a first part intersecting with the seal channel at a first point and a second part intersecting with the seal channel at a second point. The first part of the coolant flow passage is configured to provide hydraulic fluid to the seal channel such that, at the first point, a first portion of the hydraulic fluid flows in a first direction around the loop and a second portion of the hydraulic fluid flows in a second direction opposite to the first direction around the loop. At the second point, the first portion of hydraulic fluid and the second portion of hydraulic fluid are configured to flow into the second part of the coolant flow passage.

Abstract: A mechanical transmission system that transmits motions and forces from one location to another while allowing the relative position/orientation of the two locations to change continuously is disclosed. The system can be used to actuate the joints and tooling of a robotic arm using stationary motors in the robot's base. Since the motors do not contribute any weight or inertia to the arm, this yields a lightweight and agile arm that is more human safe. The transmission includes a controller hydraulic cylinder connected to a remote cylinder by a tubing assembly, which contains hydraulic fluid, and a wire cable. The fluid transmits pushing forces between pistons of the cylinders, while the cable transmits pulling forces. The tubing assembly allows the cylinders to move in space relative to one another.

Abstract: A device and a system for controlling the turning of an object includes a shaft enclosing a first space, and a sleeve forming a second space between the shaft and the sleeve. Movement of the sleeve is transmitted to movement of the object. The device further comprises a housing comprising means for rotating the shaft and at least one inlet for a lubricant, and a lubricant collector. The shaft has a first through hole extending from the first space to the second space, and the sleeve has at least a second through hole for providing the second space in fluid communication with the lubricant collector. The housing is in fluid communication with the second space, and the first space is pressurizeable for causing the lubricant in the second space to be displaced through the second through hole and collected in the lubricant collector.

Abstract: An indirect hydraulic load hierarchical control system and method for a wave energy device includes a first hydraulic cylinder group, a second hydraulic cylinder group, a third hydraulic cylinder group, a high-pressure energy accumulator group, a pressure detection control module, a first hydraulic power generator set, a second hydraulic power generator set and a third hydraulic power generator set. A detection end of the pressure detection control module is used for acquiring an internal pressure of the high-pressure energy accumulator group, comparing the internal pressure with a preset pressure level, and respectively controlling the on-off of reversing valves and electromagnetic valves according to a comparison result. The present invention has the beneficial effects that all hydraulic loads can be automatically loaded or automatically unloaded, so that the wave energy device operates in a full load state or in an optimal energy conversion efficiency state.

Abstract: A cylinder device for a hydraulic lifting device has a housing and a piston rod axially movable relative to the housing. A rotary element is mounted on the housing in such a way that a rotary movement of the rotary element relative to the housing is possible and an axial movement of the rotary element relative to the housing is prevented. The piston rod has a movement transmission element, wherein the movement transmission element translates an axial movement of the piston rod into a rotary movement of the rotary element. A sensor unit is attached to the housing, which detects the rotary movement of the rotary element. Furthermore, a hydraulic lifting device with such a cylinder device, a chassis of a mobile device with a lifting device and a mobile device with a chassis are provided.

Abstract: A hydraulic circuit includes a prime mover that is configured to generate an oscillating flow of hydraulic fluid, and an actuator that is driven by the prime mover and configured to provide oscillating motion and to be connected to a load in each direction of the motion. The hydraulic circuit also includes a reclamation device that is disposed in the hydraulic circuit between the prime mover and the actuator. The reclamation device captures and stores a portion of hydraulic fluid displaced from the actuator during a transition between opposed motions, where the portion of hydraulic fluid corresponds to an amount of hydraulic fluid equal to a volume of fluid required to compensate for compression of fluid within the hydraulic circuit due to system pressure and load pressure. The stored fluid is used by the circuit in a subsequent motion.

Abstract: A four-quadrant radial piston hydraulic device includes a housing, plunger assemblies, an eccentric spindle rotatably disposed on the housing, pilot-operated check valves one-to-one corresponding to the plunger assemblies, two-way cartridge valves one-to-one corresponding to the plunger assemblies, a distribution shaft and a confluence plate. A reversing slide valve is disposed on the confluence plate. A working method of a four-quadrant radial piston hydraulic device is also provided. When the radial piston hydraulic device is used as a hydraulic motor and a hydraulic pump, it is capable of realizing two-way rotation, which solves a limitation of valve flow distribution in motor application.

Abstract: A working-fluid supply system includes: a first pump and a second pump driven by an engine; a first switching valve capable of switching a supply target of the second pump to either one of the discharge side and the suction side of the first pump; a first switching control unit configured to perform a switching control of the first switching valve; and a first pressure control unit configured to perform a control such that pressure on the suction side of the first pump becomes a predetermined first pressure when the first switching valve is switched such that the supply target of the second pump becomes the suction side of the first pump.

Abstract: A pump assembly for generating pressure in a brake circuit of a controllable power brake system of a motor vehicle. The pump assembly has, as a pressure generator, a piston-cylinder unit in which a piston is actuated with the aid of a piston drive. The piston drive converts a rotational movement, with which a nut of this piston drive is driven, into a translatory movement of a spindle, which is in turn connected to the piston in a rotationally fixed manner. The piston is a steel component in which a plastic deformation at a piston head forms a device for connecting the spindle to the piston in a rotationally fixed manner.