Abstract: The present invention relates to an electro-hydrostatic system (1) with a hydraulic machine (11) which is driven by an electric motor (10) and has a variable volume and/or rotational speed for providing a volumetric flow rate of a hydraulic fluid, a differential cylinder (20) with a piston surface and with an annular surface, and at least one equalization container (30, 37), wherein the drive system (1) has a closed hydraulic circuit and during operation has an overpressure relative to the environment by means of the hydraulic machine (11) and/or a pretensioning source (15, 37), and the drive system (1) provides a movement of the cylinder in a first direction by means of a volumetric flow rate of the hydraulic machine (11) and a volumetric flow rate from the equalization container (30, 37), and provides a movement in a second direction by means of a volumetric flow rate of the hydraulic machine (11) and a volumetric flow rate into the equalization container (30, 37), and a power operating mode and a speed ope

Abstract: A system for damping mass-induced vibrations in a machine having a long boom or elongate member, the movement of which causes mass-induced vibration in such boom or elongate member. The system comprises multiple pressure sensors operable to measure pressure fluctuations in the hydraulic fluid pressures in the non-load holding and load holding chambers of a hydraulic actuator connected to the boom or elongate member that result from mass-induced vibration, and a processing unit operable to control a first control valve spool in a pressure control mode and a second control valve spool in a flow control mode in order to adjust hydraulic fluid flow to the actuator's load holding chamber to dampen the mass-induced vibration. The system further comprises a control manifold fluidically interposed between the actuator and control valve spools that causes the first and second control valve spools to operate, respectively, in pressure and flow control modes.

Abstract: A hydraulic transaxle comprises an axial piston hydraulic pump having a variable displacement, and a transaxle casing incorporating the hydraulic pump. The hydraulic pump includes a movable swash plate and a pair of trunnion shafts. The transaxle casing includes a pair of side walls, and includes a pair of casing holes each of which penetrates each of the side walls between an inside and an outside of the transaxle casing. The pair of trunnion shafts are passed through the respective casing holes. The swash plate is formed with a pair of swash plate holes in the respective side portions facing the respective side walls in the inside of the transaxle casing. Proximal end portions of the respective trunnion shafts are inserted into the respective swash plate holes. A distal end portion of one of the trunnion shafts projects from the corresponding casing hole to the outside of the transaxle casing.

Abstract: A hydraulic system includes a supply line, at least one implement-based control valve, an implement-based pressure regulating valve, and a load sensing circuit. The implement-based control valve(s) is fluidly coupled to the supply line and configured to regulate a flow of the pressurized hydraulic fluid supplied through at least one downstream actuator line to at least one hydraulic actuator of the implement. The implement-based pressure regulating valve is fluidly coupled to the supply line upstream of the control valve(s) and configured to regulate a fluid pressure to be equal to or greater than a minimum fluid pressure. The load sensing circuit is fluidly coupled to the pressure regulating valve and provides a line or load pressure to the pressure regulating valve. The pressure regulating valve is configured to regulate the supply of the pressurized hydraulic fluid based on the line pressure.

Abstract: A ride control system for a power machine having a lift arm movably coupled to a frame. A hydraulic cylinder configured to selectively control movement of the lift arm relative to the frame. An accumulator is in selective communication with a first end of the hydraulic cylinder. A pressure sensor communicates a signal indicative of a hydraulic pressure at a first end of the hydraulic cylinder. A ride control circuit allows selective communication between the accumulator and the first end of the hydraulic cylinder. A controller receives the signal from the pressure sensor, and prevents communication between the accumulator and the first end of the hydraulic cylinder until the signal from the pressure sensor indicates a pressure below an initial pressure threshold value.

Abstract: Circular force generator (CFG) devices, systems, and methods are disclosed having indirectly driven imbalanced rotors for generating vibrations and/or imparting vibration control. A CFG device (10) includes a first set of imbalanced rotors (12) disposed about a center point and a second set of imbalanced rotors (12) disposed about the center point. The first set of imbalanced rotors is configured to co-rotate synchronously. The second set of imbalanced rotors is configured to co-rotate synchronously. The first and second sets of imbalanced rotors are configured to create a controllable rotating force vector having a controllable magnitude and phase about the center point. A CFG system includes a controller and one or more CFG devices configured to receive control commands from the controller. A method of generating a force via a CFG device includes receiving a force command and generating a force in response to receiving the force command.

Abstract: A drive apparatus for a vehicle includes a hydraulic pump connected to two separate hydraulic motors by a center section. A center section hydraulically connects the pump and the motors by means of a pump running surface connected to two motor running surfaces by hydraulic porting. A plurality of projections extend from the center section. Two of the projections have a first flat surface that is coplanar with the pump running surface, and a third projection has a separate flat surface that is parallel to and offset from the pump running surface. The third projection may be disposed between the two motor running surfaces.

Abstract: An actuator according to the present invention includes a telescopic body, a tank, a first opening/closing valve provided in a first passage that connects a rod side chamber to a piston side chamber, a second opening/closing valve provided in a second passage that connects the piston side chamber to the tank, a pump that supplies a fluid to the rod side chamber, a motor that, drives the pump, an exhaust passage that connects the rod side chamber to the tank, and a valve element provided in the exhaust passage, wherein a telescopic unit is formed by integrating the telescopic body, the first opening/closing valve, and the second opening/closing valve, a driving unit is formed by integrating the pump and the motor, and the telescopic unit and the driving unit are provided as separate bodies.

Abstract: A shock absorber includes a piston joined to a piston rod that proceeds into and recedes from a cylinder, an extension-side chamber and a compression-side chamber that are separated from each other by the piston and have a working fluid reserved therein, first and second extension-side discharge passages in which the working fluid discharged from the extension-side chamber flows, an extension-side supply passage in which the working fluid to be supplied to the compression-side chamber flows, first and second compression-side discharge passages in which the working fluid discharged from the compression-side chamber flows, and a compression-side supply passage in which the working fluid to be supplied to the extension-side chamber flows. An extension-side damping valve and a compression-side damping valve are respectively provided in the first extension-side discharge passage and the first compression-side discharge passage.

Abstract: A revolution vibration suppressing method and apparatus for pump truck boom is provided. Vibration severity of the boom in the revolution direction is detected. Dynamic characteristic parameters of the boom are extracted. A control signal that can be used to control the revolving actuator to compensate the vibration severity according to the vibration severity and the dynamic characteristic parameters is calculated. The revolving actuator is driven according to the control signal to move, to suppress the revolution vibration of the boom. A revolution vibration suppression controller and a revolution vibration suppression device for a pump truck boom are provided to implement the methods. With the disclosed methods and apparatus, the vibration of a pump truck boom in the revolution direction can be suppressed, and therefore the risk of failures of the boom is decreased and the operating safety in the work is improved.

Abstract: This invention consists of the addition of a novel clutch arrangement which facilitates speed changing gears on both the output and input of the transmission and provides for a compact packaging configuration for a plurality of hydraulic pump/motors. The use of a small accumulator without a valve and a related reservoir absorbs the pressure shocks from rapidly opening and closing the valves that that select or de-select the pump/motors. It is also disclosed that two adjacent pump/motors on the same shaft can be constructed such that they share an input or output port thereby reducing the size of the combination. The transmission can perform the retarder function by placing a flow retarding valve in the re-circulating path in one or more of the pump/motors.

Abstract: A device for compensating for hydraulic effective pressures in a hydraulic accumulator (9) and a hydraulic actuator (5) of a hydraulic system (11, 13) has a valve arrangement (27) for blocking a connection between the hydraulic actuator (5) and hydraulic accumulator (9) and has a control valve device (11) performing a pressure compensation when a predetermined difference in effective pressures is exceeded.

Abstract: A vibration control device for railroad vehicle includes an actuator with a cylinder coupled to a truck of a railroad vehicle, a piston, a rod coupled to the piston and a vehicle body, a rod-side chamber and a piston-side chamber in the cylinder, a tank, a first on-off valve disposed at an intermediate position of a first passage communicating between the rod-side chamber and the piston-side chamber, a second on-off valve disposed at an intermediate position of a second passage communicating between the piston-side chamber and the tank, and a pump for supplying fluid to the rod-side chamber. A warm-up operation of the actuator is performed by opening the first and second on-off valves and driving the pump after the vibration control device is started and before a transition is made to a normal control mode for suppressing the vibration of the vehicle body.

Abstract: A work vehicle comprises a chassis, a compartment, a vibratory power unit positioned in the compartment and mounted to the chassis to move in vibration relative to the chassis, a pump, a fluid attenuator, and a rigid tube. The pump and the fluid attenuator are mounted to the vibratory power unit to move in vibration relative to the chassis. The rigid tube interconnects the pump and the fluid attenuator for fluid communication therebetween.

Abstract: A method for adapting stiffness in a variable stiffness actuator includes a member configured to transmit motion that is connected to a fluidic circuit, into which a control fluid circulates. The fluidic circuit includes a supply and distribution unit of the control fluid having a reservoir of the control fluid and a pumping unit. The supply and distribution unit includes two distribution lines of the control fluid, which are fluidly connected to the actuator such that an increase and/or decrease in the pressure of the control fluid activates the member that transmits motion. The stiffness of the actuator is adapted by adapting the pressure of the control fluid into the two distribution lines. The present invention includes also a variable stiffness actuator utilizing the above method for adapting stiffness.

Abstract: A vibration damping system by means of a hydraulic actuation system, in particular for rolling mills, comprising at least one hydraulic actuator (1) having a movable part (11) and a corresponding hydraulic feeding circuit (2), and hydraulic damping means (3) for a vibrating force acting on the movable part (11) of the hydraulic actuator (1); the damping means (3) being connected to the hydraulic circuit (2) to actuate a damping of the vibrating force, wherein that the damping means (3) comprise a double chamber cylinder (31) having a first chamber (34) hydraulically connected to the hydraulic circuit (2), and a movable part (35) connected to an electric damping part (32), with the first chamber (34) hydraulically connected to and communicating with the second chamber (33) of the double chamber cylinder (31) by means of a calibrated pipe (36).

Abstract: A vibration suppressor is disclosed that is configured for use in a system having a hose under pulsating hydraulic pressure. The pulsating hydraulic pressure causes vibration of the hose at the pulsation frequency. The vibration suppressor is applied to the hose and is constructed to have a resonant frequency slightly below the pulsation frequency where the pulsating hydraulic pressure is at a peak level, due to, but not limited to, the existence of a resonance in the hydraulic system.

Abstract: The device to actively control the vibrations of an articulated arm consisting of a plurality of segments each comprising at least its own actuator associated with a hydraulic drive circuit including a block valve. At least one of said actuators is associated with an hydraulic control circuit of the vibrations, comprising at least a sensor able to detect the vibrations and/or the position of one or more segments, a processing unit to process the signals of the sensor/sensors and a pump commanded by the electronic command board and cooperating with said block valve. The hydraulic control circuit is associated with the hydraulic drive circuit.

Abstract: A hydraulic pilot control arrangement for a spool valve is provided, wherein the spool of the spool valve is biased towards a central position. The arrangement includes a first and a second pilot hydraulic line connected to opposite sides of the spool of the spool valve and a pilot pressure regulating arrangement is provided for selectively establishing or removing a pilot pressure in each of the first and second lines. The arrangement includes a damping device including a chamber divided into a first and a second pressure compartment by a sliding piston, the first and second pressure compartments being connected respectively to the first and second pilot hydraulic lines, and the piston is biased towards a rest position in the chamber.

Abstract: A tuning cable for hydraulic system noise reduction is secured to a secondary fitting where the secondary fitting is mounted in a primary fitting using a pressed-in fit, a threaded connection or a slip fit after a tuning cable is installed in the secondary fitting by crimping the secondary fitting. The primary fitting is secured to a hydraulic connector which is also secured to a hydraulic hose to form a hydraulic hose assembly. In an alternative embodiment the secondary fitting is slipped directly into the hydraulic connector.

Abstract: The present invention discloses a revolution vibration suppressing method for pump truck boom, comprising: detecting the vibration severity of the boom in the revolution direction; extracting dynamic characteristic parameters of the boom; calculating a control signal that can be used to control the revolving actuator to compensate the vibration severity according to the vibration severity and the dynamic characteristic parameters extracted; and driving the revolving actuator according to the control signal to move, to suppress the revolution vibration of the boom. In addition, the present invention further provides a revolution vibration suppression controller and a revolution vibration suppression device for a pump truck boom, and a pump truck comprising the device. With the technical scheme described above, the vibration of a pump truck boom in the revolution direction can be suppressed, and therefore the risk of failures of the boom is decreased and the operating safety in the work is improved.

Abstract: Disclosed is a hybrid excavator which reduces the impact generated at the start of the operation of the boom cylinder, or the like, of a hybrid excavator. The hybrid excavator according to the present invention comprises: a hydraulic pump motor connected to an electric motor and operated in the forward or reverse direction; a hydraulic cylinder connected to the hydraulic pump motor and operated in an expanding manner; a first and second hydraulic valve installed in a first and second passage, respectively, between the hydraulic pump motor and the hydraulic cylinder, for blocking the first and second passages when switched by an external control signal; a third hydraulic valve installed in the connecting path connected to first and second dividing passages.

Abstract: The present disclosure relates to an apparatus for attenuating fluid ripple in a fluid circuit. A standpipe manifold may include multiple standpipes coupled to a fluid conduit at a same axial location. The multiple standpipes may be configured to attenuate different frequencies of fluid pressure waves passing through the fluid conduit.

Abstract: A hydraulic system comprising a receiving body with electrohydraulic valve, with at least one hydraulic pump, and with channels for connecting the pump to at least one hydraulic load. A pulsation situation arises as a result of the delivery of a pressure medium by the pump and/or as a result of pressure medium being withdrawn by the load. At least one damping unit is provided, having a plurality of pulsation damping means such as, in particular, a damping chamber, and orifice. The hydraulic system provides a uniform and cost-effective solution for different operating situations and prevents a decrease in comfort. The damping unit has at least one switching means for adjusting the action of said damping unit to a varied pulsation situation by connecting or disconnecting one or more damping means.

Abstract: A hydraulic oscillating motor which has at least two working chambers which are coupled via pressure lines to a device for pressure compensation. A first working chamber is connected to a first pressure line and a second working chamber is connected to a second pressure line. The motor further has a device for pressure compensation with a first compensating cylinder and a second compensating cylinder. Each of the compensating cylinders has in each case one compensating volume and in each case one elastic force store for delimiting the respective compensating volume. The compensating volume of the first compensating cylinder is connected to the first pressure line, and the compensating volume of the second compensating cylinder is connected to the second pressure line.

Abstract: A hydraulic system includes a power source, a fluid displacement assembly, a plurality of actuators, a plurality of control valves and an electronic control unit. The fluid displacement assembly is coupled to the power source. The plurality of actuators is in selective fluid communication with the fluid displacement assembly. The plurality of control valves is adapted to provide selective fluid communication between the fluid displacement assembly and the plurality of actuators. The electronic control unit is adapted to actuate the plurality of control valves, the electronic control unit receives a rotational speed of the power source, determines a firing frequency of the power source based on the rotational speed, selects a frequency of the pulse width modulation signal for the plurality of control valves based on the firing frequency of the power source, and actuates the plurality of control valves in accordance with the frequency of the pulse width modulation signal.

Abstract: An agricultural combine has a header height control circuit supplied with hydraulic fluid from a closed center pump. The pump has a variable displacement. The pump displacement is controlled by a control line connected to the pump. The control line is supplied with fluid from the feederhouse lift cylinders that passes through a valve. The valve supplies hydraulic fluid at the feederhouse lift cylinders to the control line of the pump. Upon receiving fluid from the valve the closed center pump rapidly changes its outlet pressure to match the pressure in the feederhouse lift cylinders and thus reduces the response time of the closed center pump.

Abstract: A hydraulic power output unit can be used in a hydraulic hybrid drive system for propelling a vehicle. The hydraulic power output unit includes a housing having an input shaft that extends within the housing and is adapted to be rotatably driven by a source of rotational power. A hydraulic pump is rotatably driven by the input driveshaft to pump hydraulic fluid. A vibration damper is provided within the housing for dampening vibrations in the input shaft.

Abstract: A hydraulic actuator includes an energy recuperation device which harvests the energy generated from the stroking of a shock absorber. The energy recuperation device can function in a passive energy recovery mode for the shock absorber or an active mode for the shock absorber. The energy that is generated by the energy recuperation device can be stored as fluid pressure or it can be converted to another form of energy such as electrical energy.

Abstract: A torque shock or vibrations caused by the rotary inertia of a hydrostatic continuously variable transmission is reduced to improve ride quality of a vehicle when excessive torque occurs in a torque transmission path between a crankshaft and a drive wheel. A motorcycle includes a hydrostatic continuously variable transmission rotatably driven by torque of a crankshaft of an internal combustion engine. A rear wheel is rotatably driven by torque from the transmission. A torque damper absorbs excessive torque occurring in a torque transmission path from the crankshaft to the rear wheel. The torque dampers include an input side torque damper disposed in an input side torque transmission path between the crank shaft and the transmission and an output side torque damper disposed in an output side torque transmission path between the transmission and the rear wheel.

Abstract: The invention concerns a vibration-decoupling device for a hydraulic circuit and in particular concerns a vibration-decoupling device for a hydraulic circuit used in an agricultural vehicle. The device has a fluid transfer element (3) able to be connected at one end (4) to a high pressure outlet of a hydraulic pump (1) and to transport fluid expelled from the pump. The another end (5) of the fluid transfer element (3) is moveably connected with a fixed element (11) such as a gear assembly housing so that the fluid can be passed to a hydraulic consumer. A support element (9) is moveably connected with the fixed element (11) and the fluid transfer element (3) and acts so that a force is exerted on the fluid transfer element (3) in one direction while the other end (5) of the fluid transfer element (3) and the fixed element (11) remain securely connected together.

Abstract: A hydraulic system for a mobile machine having an implement is disclosed. The hydraulic system may have a hydraulic actuator configured to move the implement, a storage device configured to store pressurized fluid, and a valve operable to fluidly communicate the storage device with the hydraulic actuator. The hydraulic system may also have a sensor associated with the mobile machine to generate a signal indicative of a speed of the mobile machine, and a controller in communication with the valve and the sensor. The controller may be configured to compare the speed of the mobile machine to a setpoint and to determine an amount of time elapsed while the speed of the mobile machine exceeds the setpoint. The controller may further be configured to selectively operate the valve to fluidly communicate the storage device with the actuator based on the elapsed amount of time and the speed to cushion movement of the implement.

Abstract: A machine is provided with a first work arm, at least one first cylinder having a first lift chamber configured for receiving pressurized fluid so as to lift the first work arm, and a first accumulator associated with the first lift chamber of the first cylinder. The machine further includes a second work arm, at least one second cylinder having a second lift chamber configured for receiving pressurized fluid so as to lift the second work arm, and a second accumulator associated with the second lift chamber of the second cylinder. A control arrangement is provided for selectively fluidly connecting one or both of the first and second accumulators with the associated first and second lift chambers.

Abstract: A method of limiting jerk in a hydraulic system of a machine includes defining a maximum pressure rate. An output pressure of a hydraulic fluid is continuously measured over time from a work port of a hydraulic valve to determine an output pressure rate. The measured output pressure rate is compared to the maximum pressure rate. A requested flow rate is adjusted when the measured output pressure rate is greater than the maximum pressure rate to decrease the pressure differential generated in response to changing the flow rate of the hydraulic fluid through the valve, which thereby limits a change in acceleration or deceleration of the hydraulic system to limit felt jerk in the machine.

Abstract: A cushion arrangement for smoothing stage changes in an hydraulic cylinder and including at least one compression chamber of variable volume with a movable and/or deformable chamber wall element displaceable by at least one of the pistons when approaching the transition zone between first and second stages of displacement. The compression chamber is operatively connected to a gas volume to be compressed upon displacement of the chamber wall element.

Abstract: [Summary] [Problem] To provide a load compensation device which can compensate loads on a working arm, and has excellent safety and durability. [Means of Resolution] A working arm 104 is supported by a first pivot-mounting part 103 on a supporting body 102, an actuator cylinder 105 is supported by a second pivot-mounting part 107 above the first pivot-mounting part 103, and a piston rod 108 of the actuator cylinder 105 is linked to a third pivot-mounting part 109 of the working arm 104. A piston rod 112 of a compensation cylinder 110 is linked to a movable frame 113, and a piston 112A of the compensation cylinder 110 is urged upward by means of a compression coil spring 114 which pushes the movable frame 113 upward.

Abstract: A Control apparatus for a piston/cylinder arrangement, having a valve arrangement connected to a first part space, which assumes a closed position preventing a fluid held in the first part space from flowing out if the pressure in the fluid is smaller than a pressure control value set on the valve arrangement and which assumes an opening position if the pressure in the fluid is greater than the set pressure control value, and having a priming device which is coupled to the valve arrangement and the first part space serving to prepare for the damping of a pressure increase in the fluid which is brought about by a movement of the piston caused by a load acting on the piston in the direction of the first part space such that a pressure increase can be generated in the fluid to a predefined pressure priming value independently of the load.

Abstract: A method for springing a movement of an implement of a work machine during a movement of the work machine is provided, in which at least one hydraulic cylinder is connected to the implement for controlling its movements, comprising the steps of connecting a hydraulic machine to the hydraulic cylinder, and of controlling the hydraulic machine in response to a disturbance acting upon the implement during the movement of the work machine.

Abstract: A control method and system for controlling a hydraulically actuated mechanical arm to perform a task, the mechanical arm optionally being a hydraulically actuated excavator arm. The method can include determining a dynamic model of the motion of the hydraulic arm for each hydraulic arm link by relating the input signal vector for each respective link to the output signal vector for the same link. Also the method can include determining an error signal for each link as the weighted sum of the differences between a measured position and a reference position and between the time derivatives of the measured position and the time derivatives of the reference position for each respective link. The weights used in the determination of the error signal can be determined from the constant coefficients of the dynamic model. The error signal can be applied in a closed negative feedback control loop to diminish or eliminate the error signal for each respective link.

Abstract: A method for controlling an actuating device in an automated shifting system of a motor vehicle. The position of the actuating device is determined by a path measurement system. The actuating device can be controlled by a pressure regulation device, including a pressure medium reservoir, at least two pressure lines and a switching valve for connecting a first pressure line to a pressure medium line leading to the pressure chamber of the actuating device, and a pressure regulating device for adapting the pressure level of the main pressure line to the control pressure level of the actuating device. By appropriately controlling the pressure regulation device before the piston of the actuating device moves in the intended direction, it is moved in the direction opposite to the intended movement direction. When this movement direction is registered the movement direction is changed to the intended movement direction.

Abstract: The present invention discloses a method and device for suppressing vibration of boom of concrete pump truck, in which the boom cylinder is connected with the vibration suppression cylinder; the information about hydraulic pressure in the boom cylinder and/or about changing of concrete pumping direction is monitored by a pressure sensing unit in real time; the monitored information about hydraulic pressure and/or about changing of concrete pumping direction is transmitted to the control unit for vibration suppression cylinder; the control unit for vibration suppression cylinder analyzes and processes the monitored information and adjusts the volumes of the rod side chamber and the non-rod side chamber in the vibration suppression cylinder such that the vibration suppression cylinder may generate a pulsed vibration and the pulsed vibration at the end of the boom is less than or equal to the vibration amplitude caused by the intermittent concrete supply at the end of the boom in amplitude, with a phase differen

Abstract: A hydraulic steering system has a steering linkage and an actuator actuating the steering linkage. Pressurized hydraulic fluid can be fed to the actuator and removed from the actuator through a return pipe. A device installed into the return pipe counteracts volume flow pulsations by damming up the hydraulic fluid return flow. The device dams up the hydraulic fluid only in the event of an occurrence of a volume flow pulsation.

Abstract: A hydraulic control system for controlling preferably at least two consumers, has a pump supplying the consumers with a pressure medium and having an adjustable pump capacity, an adjustable metering orifice assigned to each of the consumers, a power-beyond connection to which at least one power-beyond consumer is attachable, an inlet pressure scale connected downstream of the pump and provided in a pressure medium flow path between the pump and at least one of the two consumers, wherein the power-beyond connection branches off in the pressure medium flow path between the pump and the inlet pressure scale, a spring with a force acting upon the inlet pressure scale in a closing direction, an inlet having a pressure acting upon the inlet pressure scale in an opening direction, wherein the inlet pressure scale is configured so that it is actable upon in the closing direction selectively by either a highest load pressure or by a pressure that is greater than the highest load pressure.

Abstract: A cylinder device (1) according to the present invention includes: a cylinder (2); a piston (3) slidably inserted into the cylinder (2); a rod (4) inserted into the cylinder (2) and connected to the piston (3); a rod-side chamber (5) and a piston-side chamber (6) partitioned by the piston (3) within the cylinder (2); a first on-off valve (9) provided in the middle of a first passage (8) allowing the rod-side chamber (5) to communicate with the piston-side chamber (6); a second on-off valve (11) provided in the middle of a second passage (10) allowing the piston-side chamber (6) to communicate with the tank (7); and a pump (12) for supplying liquid to the rod-side chamber (5).

Abstract: A hydraulic control system for controlling preferably at least two consumers, has a pump with an adjustable delivery quantity supplying pressure fluid, an adjustable metering orifice with which the consumers are each associatable, a power beyond connection to which at least one power beyond consumer is connectable, an inlet pressure governor unit situated downstream of the pump and acted on in a closing direction by a load pressure of the consumers or of the at least one power beyond consumer, the inlet pressure governor unit being provided in a pressure fluid flow path between the pump and at least one of the two consumers, while the power beyond connection branching off from a pressure fluid flow path between the pump and the inlet pressure governor unit, a tank, the inlet pressure governor unit in a spring-prestressed position closing a connection to the at least one of the two consumers and the tank, and in another position a pressure fluid connection to the tank is opened, the inlet pressure governor uni

Abstract: The invention relates to a hydrodynamic torque converter having an impeller wheel, a turbine wheel and an oscillation damper which is accommodated in the converter housing, and a converter lockup clutch. Two damper stages are arranged here as a serial damper between the output hub of the torque converter and the converter lockup clutch, and a damper stage is arranged between the turbine wheel and the output hub. In order to improve the damping properties, a rotary oscillation absorber is additionally provided which is arranged between the dampers and is also connected to the turbine wheel in a rotationally fixed fashion.

Abstract: An apparatus for easing an impact on a boom of an excavator and a method of controlling the same are disclosed, which can minimize the vibration occurring in the boom due to the impact on a boom cylinder by actively controlling an amount of hydraulic fluid being supplied to the boom cylinder when the operation of the boom cylinder is suddenly stopped due to an operator's sudden manipulation of an operation lever for a working device.

Abstract: An arrangement for delivering hydraulic fluid to at least one hydraulic actuator of a work vehicle for moving a work implement and/or steering the vehicle includes at least two pumps which are adapted to be operatively driven by a power source and adapted to operatively drive said at least one hydraulic actuator via hydraulic fluid. A first pump is operated with a phase shift relative to a second pump.

Abstract: A hydraulic system for a vehicle, comprising a hydraulic actuation device for moving one or more moveable components of the vehicle. The actuation device comprises a hydraulic pump with an associated drive means, a reservoir for hydraulic fluid as well as one or more hydraulic actuators connected to the pump through hydraulic hoses. The hydraulic actuators act on the one or more moveable components. The pump is designed to supply pressurized hydraulic fluid to the one or more hydraulic actuators. A pressure ripple reduction device for reducing pressure ripples in the hydraulic fluid originating from the hydraulic pump is provided, having an expansion chamber.

Abstract: An integrated breakaway cylinder for controlling a boom of a self-propelled sprayer and method for constructing a boom assembly is disclosed in the present application. The integrated breakaway cylinder is constructed from a first stage cylinder and a second stage cylinder. The first stage cylinder is configured in a rod and barrel arrangement. The second stage cylinder is also configured in a rod and barrel arrangement, with the barrel of the first stage cylinder serving as the rod of the second stage cylinder. The first stage cylinder operates to extend and retract a boom. The second stage cylinder operates to absorb shock from inertia or the boom impacting an object. The design of various embodiments of the present invention couples the operation of maneuvering a boom with shock absorption into a single integrated cylinder.