Abstract: Some of the present systems include a hydraulic power storage system having an accumulator configured to supply pressurized hydraulic fluid to a hydraulically actuated device to actuate the hydraulically actuated device and a drain in fluid communication with the accumulator and including a valve that is actuatable to drain hydraulic fluid from the hydraulic power storage system such that an internal pressure of the accumulator is reduced and a flow restrictor configured to reduce a flow rate of hydraulic fluid through the valve, a hydraulic pump configured to pressurize the accumulator, a pressure sensor configured to capture data indicative of the internal pressure of the accumulator, and a processor configured to actuate the hydraulic pump to increase the internal pressure of the accumulator if the internal pressure of the accumulator, as indicated in data captured by the pressure sensor, falls below a threshold pressure.

Abstract: A hydraulic system of a work machine includes a first hydraulic device to operate in a first operation mode while pressure of hydraulic oil supplied from a hydraulic pump via a first oil passage is equal to or higher than a first pressure threshold. The hydraulic oil in the first oil passage is to be discharged via a second oil passage. A pilot check valve is provided in the second oil passage and has a pilot port to receive a pilot pressure of the hydraulic oil. The pilot check valve is closed to stop discharging the hydraulic oil in the first oil passage through the second oil passage while the pilot pressure is lower than the fourth pressure threshold. The pilot check valve is opened while the pilot pressure is higher than or equal to the fourth pressure threshold. The first hydraulic device is a ride control device.

Abstract: When a first control valve and a second control valve are in non-neutral positions, respectively, a fifth fluid passage and a second fluid passage are closed, thereby generating a first pressure within a fifth portion of the fifth fluid passage and a second pressure within a second portion of the second fluid passage, so that the first pressure is applied to a first valve through a fourth fluid passage to move the first valve to close the third fluid passage and a second pressure is applied to the confluence valve through a first fluid passage to move the confluence valve to a confluence position. When the confluence valve is in the confluence position, the confluence valve directs working fluid from a first working fluid supply to the second control valve.

Abstract: A hydraulic system includes a first supply line connecting a boom control valve and a bottom side of a boom cylinder, a second supply line connecting the boom control valve and a rod side of the boom cylinder, a leveling switch valve having: a first operating position allowing a leveling operation of a working tool; and a first stopping position allowing the leveling operation to stop, a ride controller including: a ride-control switch valve connected to a branched fluid line branched from the first supply line; and an accumulator configured to perform an anti-vibrating operation for suppressing a pressure fluctuation of the boom cylinder, and a drain fluid line to discharge operation fluid in a downstream section extending from the leveling switch valve to the rod side of the boom cylinder in the second supply line when the leveling switch valve is switched to the first stopping position.

Abstract: A system and method for the controlled lowering and lifting of a load are disclosed. The system and method may include operating a work machine having a hydraulic system including a hydraulic actuator for supporting a load, a first control valve in fluid communication with the actuator, and a controller for operating the first control valve. In one embodiment, the controller includes a first algorithm for operating the first control valve in a load lowering operation. When an operational fault within the hydraulic system is detected, the controller can be configured to enter into a safe lowering mode. In the safe lowering mode, the first algorithm is disabled and a pulse width modulation (PWM) current is sent from the controller to the first control valve. A user interface is provided to allow an operator to control the PWM current duty ratio to allow the load supported by the actuator to be lowered.

Abstract: A construction machine according to an exemplary embodiment of the present invention includes: an engine; a boom cylinder which is divided into a head side and a rod side; a regeneration line through which hydraulic fluid discharged from the head side of the boom cylinder moves when the boom descends; a regeneration motor which is connected with the regeneration line and is operated, and assists the engine; a pilot pump which generates a pilot pressure; a pilot line through which pilot hydraulic fluid discharged from the pilot pump moves; a regeneration connection line which connects the pilot line and the regeneration line; an on/off valve installed in the regeneration connection line; and a control device which closes the on/off valve when a pressure of the pilot line drops below a predetermined pressure or the hydraulic fluid discharged from the boom cylinder is supplied to the regeneration motor.

Abstract: A fluid container for releasable connection to a vehicle component, wherein the fluid container has at least one fastening lug with an opening which is aligned with a plug-through opening in the vehicle component and the connection is secured by a locking pin which can be extended into the plug-through opening and the opening and/or opening and can be locked in an end position by a rectilinear plug-in movement in a plug-in direction; in order to increase the load-bearing capacity of the connection and to simplify the installation, it is proposed that the fastening lug has a locking device which is arranged in alignment with the respective opening and the locking device includes at least two elastically resilient tabs which act in a latching manner on a thickened locking portion of the locking pin and thereby secure the locking pin in its axial direction.

Abstract: A main flow path that introduces high-pressure air to an air cylinder, or discharges exhaust air therefrom, includes a sub flow path provided alongside the main flow path; an exhaust flow rate adjustment unit that suppresses the operation speed of the air cylinder by adjusting the flow rate of the exhaust air flowing through the sub flow path; and a switching valve that is connected between the air cylinder, the main flow path and the sub flow path, and that connects the main flow path and the sub flow path to the air cylinder in a switching manner. The switching valve is constituted by a spool valve.

Abstract: An actuator including a housing, an actuator rod and a snubber assembly. The actuator has an axis, the housing has a first end and an aperture positioned at the first end of the housing, and the actuator rod extends through the aperture along the axis of the actuator. The snubber assembly is mounted at the first end of the housing, and includes one or more energy absorbing devices. The snubber assembly is positioned on the housing such that an axis of each of the one or more energy absorbing devices is offset relative to the axis of the actuator. The snubber assembly is configured such that the one or more energy absorbing devices provide bidirectional end-of-stroke damping.

Abstract: To provide a construction machine that has a hydraulic system mounted thereon in which a closed-circuit pump, and an open-circuit pump and a proportional valve are arranged as a pair, and that makes it possible to use an unused open-circuit pump or proportional valve to accelerate the speed of a single rod hydraulic cylinder when the single rod hydraulic cylinder and a hydraulic motor are driven simultaneously. A controller (51) controls a cap-side selector valve (46) and a rod-side selector valve (47) such that a particular open-circuit pump (15) not connected to a single rod hydraulic cylinder (3) is connected to the single rod hydraulic cylinder, and controls an opening area of a particular proportional valve (49) provided on a flow line that connects a delivery port of the particular open-circuit pump to a tank, when the single rod hydraulic cylinder and a hydraulic motor (7) are driven simultaneously.

Abstract: A work vehicle includes an axle frame extending in a left-right direction, a cylinder coupled to the axle frame, and a first supply conduit connected to the cylinder and configured to supply hydraulic fluid to the cylinder. The first supply conduit is fixed to the axle frame.

Abstract: A radial piston hydraulic motor comprising a box frame with a cam ring connected thereto, pistons in a piston frame and press rollers in the pistons, which press rollers can be pressed by means of the pressure of a hydraulic fluid, such as hydraulic oil, against an inner surface of the cam ring. The piston frame comprises connections between the interior space and passages, and a shutter valve is provided within each connection for controlling the hydraulic fluid flow through the connection between the passages and the interior space. The shutter valve is arranged to allow hydraulic fluid to flow from the passage into the interior space, when the pressure in the working pressure inlet passage, in the return passage and in the interior space is equal, i.e. the motor is in free-rotating state.

Abstract: A hydraulic drive system for a work machine including a hydraulic energy recovery device that is configured to perform load sensing control and accumulates hydraulic fluid that returns from a hydraulic cylinder in operation of lowering a front work implement into an accumulator includes, in order to prevent, when operation other than operation of lowering the front work implement is to be performed, hydraulic energy accumulated in the accumulator from being consumed uselessly, a regeneration selector valve in a hydraulic line for regenerating the hydraulic fluid accumulated in the accumulator into a hydraulic fluid supply line of a main pump. The regeneration selector valve is controlled such that, only when saturation occurs with the main pump, flow from the accumulator to the hydraulic fluid supply line is permitted.

Abstract: A hydraulic system includes a first output fluid tube connecting between a hydraulic pump to output operation fluid and a first operation valve to change a first pilot pressure of the operation fluid, a second output fluid tube connected between the hydraulic pump and a second operation valve to change a second pilot pressure of the operation fluid, a switching valve provided in the second output fluid tube, and a warm-up fluid tube connected between the first operation valve and the switching valve, wherein the switching valve is switched between a first position allowing the operation fluid to be drained through the first output fluid tube, the first operation valve, the warm-up fluid tube and the switching valve, and a second position allowing the operation fluid to be supplied through second output fluid tube to the second operation valve.

Abstract: A hydraulic pressure supply device includes: a hydraulic pump capable of changing a discharge capacity; an electric motor capable of changing a rotational frequency; a discharge capacity adjustment mechanism capable of adjusting the discharge capacity of the pump between a maximum and minimum discharge capacity; a pressure detector configured to detect pressure of an operating liquid discharged from the pump; a rotational frequency detector configured to detect the rotational frequency of the motor; and a controller configured to control operations of the motor and adjustment mechanism based on the rotational frequency, detected by the detector, to keep pressure of an actuator at arbitrary pressure, wherein, the controller controls the operation of the adjustment mechanism so the discharge capacity of the pump becomes a set lower limit discharge capacity. The set lower limit discharge capacity is set to be larger than the minimum discharge capacity and be adjustable by the controller.

Abstract: A torque converter includes an impeller and a cover rotationally fixed to the impeller. The cover has opposing inner and outer surfaces and a through hole extending from the inner surface to the outer surface. A stud is attached to the cover. The stud has a head and a shank extending from the head. The head defines an annular projection circumscribing the shank and raised from the head. The stud is disposed on the cover with the shank extending through the hole to project from the outer surface and with the head being connected to the cover by coalescence between the annular projection and the inner surface creating a hermetic seal around the hole.

Abstract: A system including a pneumatic actuator with an actuator member and a compressed air supply device which is configured to apply compressed air to the pneumatic actuator in order to set the actuator member in an actuator member movement towards an end position of the pneumatic actuator, wherein the compressed air supply device is further configured to provide an end position damping for the actuator member movement and, during the end position damping, to adjust a conductance value of a discharge valve, via which the compressed air supply device discharges compressed air from a pressure chamber of the pneumatic actuator which pressure chamber counteracts the actuator member movement, in accordance with a conductance characteristic in dependence of a driving force acting on the actuator member.

Abstract: The present disclosure relates to a motion control unit that is capable of receiving electrical power from an electrical power source and hydraulic power from a hydraulic power source. The motion control is configured to produce a blended power output derived from the electrical and hydraulic power which can be used to power a hydraulic actuator. The motion control unit can also split hydraulic power recovered from hydraulic actuator to the electrical power source and the hydraulic power source.

Abstract: A piston-cylinder unit having a cylinder housing (1) with a cylinder interior (2) and a piston (3) arranged in cylinder interior (2), from which a piston rod (4) starts and is guided out from the cylinder housing (1) through an opening and at the same time is sealed with respect to the cylinder housing (1) by a piston rod seal (12) arranged on the cylinder housing (1). A sliding sleeve (11) made of plastic and entrained by the piston rod (4) is arranged on the piston rod (4), and the piston rod seal (12) bears against said sliding sleeve.

Abstract: A control device of a loading machine includes an adjustment determination unit and an operation signal output unit. The loading machine includes a swing motor and a swing body. The adjustment determination unit determines whether or not an angle formed by an azimuth direction of a swing body when the swing body stops and a target stop azimuth direction is less than an allowable angle based on an azimuth direction, a swing speed, and the target stop azimuth direction of the swing body during braking of the swing motor. The operation signal output unit outputs a swing control signal for driving the swing motor in a case in which it is determined that the angle formed by the azimuth direction of the swing body when the swing body stops and the target stop azimuth direction is equal to or greater than the allowable angle.