Abstract: A construction machine is provided which includes a hydraulic closed circuit in which a single rod hydraulic cylinder is driven directly by a bidirectionally tiltable variable displacement pump and can stably speed up the contraction action of the single rod hydraulic cylinder. In the case where a contraction action of a hydraulic cylinder 10 is instructed through an operation lever 30, when a differential pressure obtained by subtracting the pressure of a cap chamber 10a from the pressure of a rod chamber 10b is equal to or lower than a first threshold value a set to a level equal to or higher than a selection setting pressure of a flushing valve 14, a controller 20 closes a rod side selector valve 12b to disable rod assist action for supplying hydraulic fluid from a second hydraulic pump 8 to the rod chamber, and when the differential pressure is higher than the first threshold value, the controller 20 opens the rod side selector valve to enable the rod assist action.

Abstract: A piston is the driven component within a pump. The piston is driven along a longitudinal axis to pump a fluid through the pump. The fluid flows through the piston between an upstream end of the pump and a downstream end of the pump. The piston outputs the fluid into the downstream end of the pump at a vector offset from the longitudinal axis, thereby inducing rotation of the piston throughout the pumping process. Rotating the piston encourages even wear on various components within the pump, such as sealing rings surrounding the piston, thereby increasing the lifespan of the components and increasing the efficiency of the pump.

Abstract: A pump fluid end includes a body that defines a plunger bore and a working fluid bore that intersects the plunger bore to form a cross bore. A packing bore is defined in the plunger bore and includes a packing sleeve bore, a taper relief bore, and a transition bore. The packing sleeve bore transitions to the taper relief bore at a radial shoulder and the taper relief bore transitions to the plunger bore across the transition bore. The transition bore extends between an external corner contiguous with the plunger bore and an internal corner contiguous with the taper relief bore and at least one of the external and internal corners is rounded and exhibits a radius. The packing bore is treated with a surface pre-stressing treatment.

Abstract: A stabilizer system includes a first object that moves relative to a second object and includes a first actuator coupled to a first wear pad. The first actuator drives the first wear pad to contact a first side of the second object to control motion of the first object relative to the second object. The first actuator operates in a first mode and in a second mode. While operating in the first mode, the first actuator applies a first force to the first wear pad to block the motion of first object relative to the second object. While the first actuator is operating in the second mode, the first actuator applies a second force, lower than the first force, to the first wear pad to enable the motion of the first object relative to the second object.

Abstract: The invention relates to a hydraulic drive having a differential cylinder which has a cylinder piston and a piston rod which is connected to the cylinder piston. The cylinder piston is arranged in a displaceable manner in a cylinder chamber in order to extend and retract piston rod. The cylinder chamber is separated by cylinder piston into a piston side, and a ring side with piston rod, each with a variable volume. The piston side and ring side are separated from one another by the piston and are connected to one another in a fluid conducting manner via a short-circuit line. The short-circuit line includes a switching valve for optionally shutting off short-circuit line in a fluid-tight manner. A switching valve can be switched into its blocking position at least indirectly in dependence on the pressure on piston side of cylinder chamber.

Abstract: 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.

Abstract: A hydraulic fluid cylinder is equipped with a cylinder tube, a piston unit, and a piston rod. The piston unit has a piston body comprising a plurality of members and provided with a gasket-mounting groove. The piston body has a first piston member and a second piston member which are layered in the axial direction. The gasket-mounting groove is formed from a combination of at least two members. A thin section exhibiting depth in the axial direction is provided in the first piston member and/or the second piston member.

Abstract: A hydraulic actuator; a control valve that controls supply and discharge of hydraulic oil to and from the hydraulic actuator; a pilot operation valve connected to the operation valve by a pair of pilot lines; a proportional solenoid pressure-reducing valve provided on at least one of the pair of pilot lines; an operation detector that outputs an operation amount signal in accordance with an inclination angle of an operating lever of the pilot operation valve; and a controller that controls the proportional solenoid pressure-reducing valve such that, from immediately after a change amount per unit time in the operation amount signal outputted from the operation detector has decreased by a threshold value or more, a pilot port pressure of the control valve gradually decreases to zero due to communication of a secondary pressure port and a tank port of the proportional solenoid pressure-reducing valve with each other.

Abstract: This invention is a high-volume large diaphragm which provides a pair of support sections specially configured to withstand the stresses implemented by an eccentrically actuated pushrod diaphragm pump. The pair of support sections is comprised of an interior support section and an exterior support section that are vertically offset relative to each other's placement on the wall of the high-volume large diaphragm. It is additionally anticipated that more than one pair of offset interior and exterior support sections can be provided on high-volume large diaphragms with significantly greater wall height.

Abstract: To utilize and protect a mechanical load torque range of a servo drive in combination with a pump, a control unit is given a target system pressure as a reference variable and an actual system pressure as a control variable. An electric motor torque acting on a pump of the servo drive is specified by the control unit to an electric motor of the servo drive, a volume flow at the hydraulic load is generated by the pump, by which a mechanical load torque sets it at the electric motor and the actual system pressure is produced in the hydraulic load via the volume flow. A dynamic system variable of the hydraulic system is transmitted to the limiting unit. The limiting unit limits the motor torque transmitted by the control unit to the electric motor as a function of the value of the system variable.

Abstract: Various embodiments related to hydraulic actuators and active suspension systems as well as their methods of use are described.

Abstract: A hydraulic driving device of an industrial vehicle includes: a tank which stores hydraulic oil; a hydraulic pump which includes a suction port sucking the hydraulic oil and a discharge port discharging the hydraulic oil; a hydraulic cylinder which is driven by the hydraulic oil discharged from the discharge port of the hydraulic pump; a direction switching valve which is disposed among the hydraulic pump, the tank, and the hydraulic cylinder and switches a hydraulic oil flow direction in response to an operation state of operation means for driving the hydraulic cylinder; in which the direction switching valve includes a main spool which moves in response to the operation state of the operation means and a flow regulator which is disposed inside the main spool to control a flow rate of the hydraulic oil flowing from the hydraulic cylinder to the tank.

Abstract: A torque fluctuation inhibiting device for inhibiting torque fluctuations in a rotor to which a torque is inputted is disclosed. The torque fluctuation inhibiting device comprises a mass body, a plurality of drag mechanisms, and a restriction mechanism. The mass body is disposed to be rotatable with the rotor and to be rotatable relative to the rotor. Each of the plurality of drag mechanisms is for generating a circumferential force when a relative displacement is produced between the rotor and the mass body in a rotational direction. The circumferential force is directed to reduce the relative displacement. The restriction mechanism is for restricting actuation of one or more of the plurality of drag mechanisms.

Abstract: An open center (OC)-open center load sense (OCLS) conversion valve and hydraulic circuits therewith configured to control flow from a hydraulic pump to multiple hydraulic functions. The conversion valve includes cartridge, load sense, pump, first function supply, first function return, and downstream ports. When an OC cartridge is inserted in the cartridge port, regardless of load sense, the pump and first function supply ports are connected and the first function return and downstream ports are connected. When an OCLS cartridge is inserted in the cartridge port and load sense is detected, the pump and first function supply ports are connected and the first function return and downstream ports are connected. When an OCLS cartridge is inserted in the cartridge port and load sense is not detected, the pump, first function return and downstream ports are connected.

Abstract: A hydraulic system for a transmission of a motor vehicle, the system having first and second pumps for conveying hydraulic fluid into primary and/or system-pressure circuits so that an intended pressure prevails in the circuits. The system further including liquid retention means preventing a flow of hydraulic fluid conveyed by the second pump from being conducted through the first pump when the first pump is not conveying and the second pump is conveying, and preventing a flow of hydraulic fluid conveyed by the first pump from being conducted through the second pump when the second pump is not conveying and the first pump is conveying. The system additionally including a sailing-mode lubricating valve for controlling, by an open-loop system, a flow rate of hydraulic fluid conveyed by the second pump into the primary and/or secondary system-pressure circuits such that the intended pressure is set in the system-pressure circuits.

Abstract: A hydraulic propulsion system converts heat or thermal energy into hydraulic energy, and such hydraulic energy into mechanical work. The hydraulic propulsion system includes a thermal unit, a hydraulic cylinder with pistons and springs mounted therein, one or more hydraulic motors, one or more hydraulic accumulators, and one or more electrical energy generators, as well as a plurality of flow control valves to control the flow of hydraulic fluid between the various components. The hydraulic propulsion system may be enhanced by a sonic transmission unit including a sonic wave generator.

Abstract: A cylinder driving device includes: an electric motor; a pump; a main passage and a main passage; a hydraulic cylinder; an operation check valve and an operation check valve; and a restriction valve and a restriction valve configured to restrict a flow of the working oil directed to the operation check valve and an operation check valve, wherein an opening area of the restriction valve and the restriction valve is reduced in response to an increase in a flow rate of the working oil discharged from the hydraulic cylinder to the main passage and a main passage.

Abstract: A soft robot having an integrated electrical component includes an expandable or collapsible body, the body comprising an inlet that is configured to communicate with a fluid source and a flexible strain limited layer secured to a portion of the expandable or collapsible body, wherein the strain limited layer includes at least one electrical component.

Abstract: A hydraulic system for a working machine, includes an operation member, an operation valve to change an output pressure of an operation fluid in accordance with operation of the operation member, a hydraulic device to be activated by the operation fluid outputted from the operation valve, a first fluid tube coupling the operation valve to the hydraulic device, and a bleed circuit connected to the first fluid tube and configured to output the operation fluid in the first fluid tube. The first fluid tube includes a first section fluid tube arranged in a section between the operation valve and a coupling portion coupling the first fluid tube to the bleed circuit, and a second section fluid tube arranged in a section between the coupling portion and the hydraulic device, the second section fluid tube having an inner diameter different from an inner diameter of the first section fluid tube.

Abstract: A pressurized gas-powered actuator includes a housing and a piston movably positioned within the housing. The piston has a drive pocket formed therein. A gas generator is positioned exterior of the piston and in fluid communication with the drive pocket.