Abstract: A hydraulic drive system includes a swing directional control valve 81 and a third boom directional control valve 82 that are connected to a third hydraulic pump 33. Furthermore, the hydraulic drive system includes: a second auxiliary directional control valve 84 that is connected to the third hydraulic pump 33, and is connectable with a second special hydraulic actuator 64 for driving special attachments; and a first selector valve 96 that is connected to the third hydraulic pump 33 upstream of the second auxiliary directional control valve 84, and is connectable with an additional hydraulic pump 97. The first selector valve 96 switches the hydraulic fluid source of the second special hydraulic actuator 64 connected to the second auxiliary directional control valve 84 at least between the third hydraulic pump 33 and the additional hydraulic pump 97.

Abstract: A work vehicle includes an engine, a hydrostatic transmission, a storage device storing leakage flow rate data defining a relationship between a differential pressure of hydraulic fluid between the first drive circuit and the second drive circuit and a leakage flow rate of the hydraulic fluid in the hydraulic circuit in stalling, and a controller in communication with the storage device. The hydrostatic transmission includes a traveling pump, a hydraulic circuit with first and second drive circuits, and a traveling motor. The controller is configured to determine a target traction force of the work vehicle, determine a target differential pressure that is a target value of the differential pressure from the target traction force, determine the leakage flow rate from the target differential pressure with reference to the leakage flow rate data, and determine a target flow rate of the traveling pump from the leakage flow rate.

Abstract: An object of the present invention is to provide a construction machine that allows easy and accurate calibration of a pressure sensor and enables accurate control of hydraulic actuators.

Abstract: A control system includes a variable displacement hydraulic pump, the pump having an inlet for receiving fluid, an outlet for discharging fluid under pressure, and a pump displacement input, a hydraulic motor having an inlet and an outlet, a fluid circuit including a supply conduit for conducting fluid discharged by the pump to the motor and a return conduit for returning fluid discharged by the motor to the pump, a pump displacement control cooperating with the pump displacement input in order to vary a displacement of the pump, a control circuit in communication with the pump displacement control for controlling the pump output such that the motor is driven at a constant rotational speed, and a system controller in communication with the control circuit and a remote location to transmit and receive information to and from the remote location.

Abstract: A compressor moves a fluid from an inlet to an outlet and provides a pressure differential there between due to respective pistons moving in and out of a plurality of piston chambers via a piston rod. A rotating shaft extends through a grooved end plate, and the rotating shaft is connected to either the grooved end plate or the piston rod. The grooved end plate defines an off center or eccentric groove. A bearing extends from the piston rod and fits within the groove such that when the rotational motion of the shaft rotates either the piston rod or the grooved end plate, the piston rod slides back and forth relative to the rotating shaft. Each position of the bearing within the groove determines a corresponding position of the piston rod relative to the rotating shaft. Each pair of pistons may extend from a single, continuous piston rod.

Abstract: A piston pump includes a first biasing mechanism configured to bias a swash plate in accordance with supplied control pressure, a second biasing mechanism configured to bias the swash plate against the first biasing mechanism, and a regulator configured to control the control pressure led to the first biasing mechanism in accordance with discharge pressure of the piston pump, wherein the second biasing mechanism has a pressure chamber to which the discharge pressure is led, and a control piston configured to be biased toward the swash plate by the discharge pressure led to the pressure chamber, and the regulator has a biasing member configured to bias the control piston toward the swash plate, and a control spool configured to be moved in accordance with biasing force of the biasing member, the control spool being configured to adjust fluid pressure.

Abstract: A rod assembly for a fluid pressure cylinder has a rod member and a packing that is mounted on an outer circumferential part of the rod member and slides along a slide hole. Assembly is simple because a conventional hard piston is not used. The assembly can be carried out simply by hand without the use of a dedicated tool. Thus, the rod assembly simplifies assembly work.

Abstract: A hydraulic thrust reverser system (TRAS) including a first return line having a first check valve therein, and a second return line having a second check valve therein, wherein the first return line and the second return line are in fluid communication with each other via a fluid restrictor located upstream of the first and second check valves, wherein the first return line extends from a piston system of the TRAS, the piston system being for moving at least one thrust reverser door, and wherein the second return line extends from a lock system of the TRAS, the lock system being for controlling locks to selectively prevent the movement of the at least one thrust reverser door.

Abstract: A hydraulic system is capable of improving the acceleration performance of a slewing motor and suppressing an increase in the flow rate of hydraulic fluid supplied to the slewing motor. The hydraulic system includes a slewing speed sensor that detects a slewing speed of a slewing body and a controller that controls a slewing motor capacity, which is a capacity of the slewing motor. The controller controls the slewing motor capacity so as to make the slewing motor capacity when the slewing speed is in a low speed range be greater than the slewing motor capacity when the slewing speed is in a high speed range.

Abstract: A method and device supply a vehicle with main and auxiliary air, wherein the device includes a compressor driven via an electric motor for generating compressed air to fill at least one main air tank for supplying pneumatic units of the vehicle, wherein the vehicle has at least one first and second power source for supplying electric energy, wherein a pneumatic actuator that upgrades the vehicle and activates the first power source is provided with the compressed air produced by the compressor in that, in that phase, the second power source feeds the electric motor of the compressor, wherein a switching valve device supplies the compressed air for upgrading to an auxiliary air tank associated with the pneumatic actuator, and otherwise the switching valve device supplies the compressed air produced by the to the main air tank.

Abstract: Hydraulic power savings for a rear module handler cylinder of a round module cotton harvester is possible by using a regenerative hydraulic arrangement for raising an empty handler and using gravity to lower the handler. A bale handler system for a cotton picker baler includes a handler for receiving a round module that is movable between upright and lowered positions and a handler cylinder operably connected to the handler. The handler cylinder system includes a regenerative valve. The regenerative valve is engaged when the handler moves to the upright position during regenerative handler raise mode of operation, the regenerative valve is not engaged when the handler moves to the lowered position during float handler lower mode of operation. While in the float handler lower mode of operation, the handler cylinder retracts and diverts an oil flow pressure from a base end to a rod end of the handler cylinder.

Abstract: A hydraulic excavator includes: a revolving frame; a work implement including a first actuator and a second actuator; a control valve; and a first pipe through which hydraulic oil flows between the control valve and each of the first actuator and the second actuator. The first pipe includes: a first conduit connected to the control valve; a second conduit and a third conduit that are connected to the first actuator and the second actuator, respectively; and a first branch portion at which the first conduit branches into the second conduit and the third conduit. A first region and a second region are on one side and the other side respectively with respect to the virtual straight line passing through a center of swing of the revolving frame. In the first region, a work implement is disposed. In the second region, the control valve and the first branch portion are disposed.

Abstract: A hydrokinetic torque coupling device for coupling together driving and driven shafts, comprises a casing, impeller and turbine wheels, a torsional vibration damper, a turbine hub non-rotatably connected to the turbine wheel, and first and second vibration absorbers. Each of the first and second vibration absorbers is one of a dynamic absorber and a pendulum oscillator. The turbine hub is non-rotatably coupled to a driven member of the torsional vibration damper. The first vibration absorber is mounted to the turbine hub and the second vibration absorber is mounted to one of the turbine hub and the casing. The first vibration absorber and the second vibration absorber are tuned to address different orders of vibrations. The dynamic absorber includes an inertial member and a connecting plate coupled to the inertial member. The pendulum oscillator includes a support member and flyweights configured to oscillate relative to the support member.

Abstract: A hydraulic system including: a pressure line; a pump; an actuator; a valve device configured to control the flow of pressurized hydraulic fluid to the actuator; an electronic control unit configured to control the valve device by a control signal proportional to the desired speed of the actuator at any given time; a pressure accumulator capable of supplying, together with the pump, pressurized hydraulic fluid for moving the actuator; a sensor device configured to measure, directly or indirectly, the amount of pressurized hydraulic fluid in the pressure accumulator at any given time; setting devices configured to set a setting signal to be proportional with the desired speed of the actuator at any given time. The electronic control unit is configured to restrict the targeted speed of the actuator not to exceed a predetermined maximum speed which is proportional to the amount of pressurized hydraulic fluid in the pressure accumulator.

Abstract: A rod assembly for a fluid pressure cylinder includes a rod member and a packing that is mounted on an outer circumferential part of the rod member and slides along a slide hole. Assembly is simple because a conventional hard piston is not used. The assembly can be carried out simply by hand without the use of a dedicated tool. Thus, the rod assembly simplifies assembly work.

Abstract: A regeneration valve includes a housing defining a first port, a second port, a third port, and a chamber fluidly communicating with the first, second, and third ports. The chamber has a valve element movable between a first position, in which the second port fluidly communicates with the first port, and a second position, in which the second port fluidly communicates with the third port. A resilient member biases the valve element towards the first position. In operation, a flow restrictor element moves between the first port and the second port for restricting fluid flow from the second port to the first port. At a predetermined flow rate between the second port and the first port, if a supply pressure of fluid at the actuation chamber exceeds the bias of the resilient member, the valve element moves to the second position for fluidly communicating the second and third ports.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing, a motor and a pump. The hydraulic control unit housing has a manifold housing portion and an accumulator housing portion. The manifold housing portion defines a fluid pathway arrangement for communicating fluid along at least a first fluid pathway. The accumulator housing portion houses an accumulator assembly having a biasing assembly and a piston. The accumulator housing portion and manifold housing portion cooperate to form an accumulator chamber that houses the biasing assembly. The motor is disposed on the first side of the manifold housing portion. The pump is disposed on a second side of the manifold portion, opposite the first side. The pump is configured to pump fluid into the accumulator chamber of the accumulator housing portion.

Abstract: A hydraulic actuator includes a hydraulic cylinder; a piston within the hydraulic cylinder and movable in response to movement of hydraulic fluid in a hydraulic circuit coupled to the hydraulic cylinder; a synchronisation connection for receiving an input from a simultaneous transmission line; and a valve for controlling the flow of hydraulic fluid in the hydraulic circuit. The valve is a rotary valve comprising: a first valve section arranged to rotate in either a first rotational direction or a second rotational direction in response to input from the simultaneous transmission line in order to open a hydraulic flow path to the cylinder and urge the piston to move along the hydraulic cylinder in a corresponding first linear direction or second linear direction; and a second valve section arranged to rotate in either the first or second rotational direction.

Abstract: A servohydraulic drive includes a hydrostatic displacement machine, an electric machine that is mechanically speed-coupled with the displacement machine, a hydraulic cylinder that is fluidically connected to the displacement machine via first and second working lines, a hydraulic accumulator, and a supply unit. The displacement machine has a stroke that is adjustable via a hydraulic adjustment device. The cylinder is configured to be activated by reversal of the fluid flow through the displacement machine in opposite directions. The accumulator is preset to a low pressure and is fluidically connected via a valve assembly in each case to the lower pressure working line. The supply unit is configured to supply the adjustment device with pressurized fluid under the necessary pressure for the adjustment regardless of the present pressure in the working lines such that the displacement machine is configured for an active and load pressure-independent adjustment of its stroke volume.

Abstract: A hydraulic fracturing pump includes a power end with a plurality of torsion tubes extending between sides of a crankcase housing in which a crankshaft is rotatably mounted. The crankshaft is coupled by piston arms to crossheads disposed to reciprocate along crosshead axes that are perpendicular to the crankshaft. Disposed within the crankcase housing are a plurality of ribs generally perpendicular to the crankshaft and extending from the base of the crankshaft housing to an upper surface of the crankshaft housing. The torsion tubes are generally adjacent the upper surface of the crankcase housing and pass perpendicularly through each of the plurality of ribs and are attached to the ribs to provide rigidity to the power end.