Abstract: A hydraulic operating device for a cooling fan of a utility vehicle includes a hydraulic motor and a fan assembly, which can be driven by the hydraulic motor for generating a cooling air stream. A hydraulic supply is adjustable in terms of its delivery volume in accordance with pressure feedback for providing pressurized hydraulic liquid. A control valve for setting, in a manner dependent on a control signal that represents a cooling demand, a volume flow that passes through the hydraulic motor, with a sensor line that is branched off in a supply line between the control valve and the hydraulic motor leading to a pressure control inlet of the hydraulic supply.

Abstract: Methods and systems for a transmission are provided herein. In one example, a hydraulic system is provided that includes a boost pump, a relief valve in fluidic communication with the boost pump and a reservoir, and a plurality of control valves in fluidic communication with the boost pump, positioned downstream of the relief valve, and in fluidic communication with a plurality of hydraulic devices. The hydraulic system further includes a controller designed to actively adjust a position of the relief valve based on an aggregate hydraulic pressure demand of the plurality of hydraulic devices to alter a boost pressure of a hydraulic fluid supplied to the plurality of control valves.

Abstract: A torque converter includes an impeller having an impeller shell and an impeller hub attached to a radially extending end of the impeller shell. The torque converter further includes a cap slidably engageable with the impeller hub. The cap includes a base and an inner ring portion. The inner ring portion is configured to be received by the impeller hub and includes an end spaced from the base. The end is configured to extend radially outside of an inner surface of the impeller hub in an installed position.

Abstract: An unloading valve includes a valve body, a valve trim, a return spring, a damping hole, and an unloading groove. A combined valve includes the unloading valve and a throttling valve. The throttling valve includes a buffer stopper and a buffer chamber. A piston rod assembly of the combined valve type buffer cylinder is provided in a cylinder body. The cylinder body includes a cylinder head flange, a cylinder bottom, and a cylinder barrel. The piston rod assembly includes a guide sleeve, a piston, and a piston rod. The combined valve is provided on the cylinder. The system is located in an unloading state in a buffering process to reduce the energy loss and heat buildup of the system, prevent the pressure impact of buffering on the system, make the system more reliable, and lower the difficulty of the original buffer valve in performance matching, installation and debugging.

Abstract: Disclosed is a master cylinder. The master cylinder includes a hydraulic block provided with a main bore formed therein in an axial direction, a first piston having one side inserted into the main bore to be displaceable and the other side exposed to an outside of the hydraulic block and connected to a brake pedal, a second piston inserted into the main bore more inside than the first piston to be displaceable, an elastic member provided between the first piston and the second piston and configured to provide a pedal feel, and a mounting block provided with a sub bore formed therein in the axial direction and the sub bore where the first piston is inserted thereinto and passes therethrough to be displaceable and having one side coupled to the other side of the hydraulic block, wherein the hydraulic block includes at least one hydraulic flow path formed through the other side, and the mounting block includes a connection flow path allowing the sub bore to communicate with the hydraulic flow path.

Abstract: A liquid delivery system includes a reciprocating drive and a liquid cylinder comprising a liquid piston, operably driven by the reciprocating drive, to pump a liquid along a flow path to a liquid applicator. The liquid delivery system includes a coupler configured to couple the liquid piston to the reciprocating drive. The coupler includes a plurality of collar elements and a biasing member configured to apply a biasing force on the plurality of collar elements to retain the collar elements in a position that forms a collar that couples the liquid piston to the reciprocating drive.

Abstract: A hydraulic system for a machine includes a hydraulic circuit, a heater, a temperature sensor, and a controller. The hydraulic circuit is configured to be coupled to an actuator of the machine. The hydraulic circuit includes a reservoir configured to store hydraulic fluid and a pump configured to drive the hydraulic fluid from the reservoir through the hydraulic circuit. The heater is configured to facilitate selectively heating the hydraulic fluid. The temperature sensor is configured to acquire temperature data indicative of a temperature of the hydraulic fluid. The controller is configured to activate the pump to drive the hydraulic fluid through the hydraulic circuit with the heater deactivated to facilitate cooling the hydraulic fluid in response to the temperature of the hydraulic fluid exceeding or approaching a maximum temperature threshold.

Abstract: A hydraulic control system for linear actuation that provides a bypass flow during startup of a lifting command, provides a split flow between a cylinder and a reservoir once a minimum operating speed of a pump has been reached, and provides complete flow to a cylinder after the minimum operating speed of the pump has been reached. This is achieved through control of a flow control valve and a proportional flow control valve by a processor.

Abstract: A locking unit for locking the movement of a piston which can be acted on with pressure of a fluid, the locking unit having the piston, an electromagnet, and at least one detent element. The detent element interacts with an armature or an armature rod of the electromagnet. The piston has at least one detent receptacle, and the piston can be secured by a retaining interaction of the detent element with the detent receptacle. The piston is adjustable between a retracted position and an extended position, and the piston can be designed at least in sections as a hollow part.

Abstract: A volume control actuator including a non-contact cylinder. An installation frame has a predetermined height and size. First and second installation spaces are defined in upper and lower portions of the installation frame, respectively. A pressing unit is vertically disposed on top of the installation frame to move a reciprocating rod in the first installation space reciprocating stroke movements. A fluid pipe is provided in the second installation space and connected to an installation plate to obtain a path through which fluid flows. Both ends of a rubber cylinder are fixed to a top surface of the installation plate and one end of the reciprocating rod. The rubber cylinder is provided in the first installation space so that the volume of the rubber cylinder changes in an expanding and contracting manner in response to the stroking of the reciprocating rod, thereby causing fluid in the fluid pipe to flow.

Abstract: The object of the invention of the present application resides in provision of a work machine that can be improved in operability at start of an action of a hydraulic actuator in a fine operation in which an operation lever is operated by a small amount. To this end, on the basis of a signal from a first timing sensor and a signal from a second timing sensor, a machine body controller controls, before the first timing is sensed, the pump delivery flow rate to a minimum delivery flow rate, controls, after the first timing is sensed but before the second timing is sensed, the pump delivery flow rate to a predetermined delivery flow rate that is greater than the minimum delivery flow rate, and controls, after the second timing is sensed, the pump delivery flow rate to a delivery flow rate according to an operation amount of the operation lever.

Abstract: A controller for electronically controlling hydraulically operated lifting arms. The controller allows a wide range of quicker movement and slower movement of the lifting arms under proportional control by the operator. An electronic servomechanism is mechanically coupled to a hydraulic valve handle to control the operation of the lifting arms. The servomechanism turns a shaft in response to a proportional controller. The valve handle controls the hydraulic valve stem, allowing the hydraulically operated lifting arms to raise, lower, grip, release, and perform auxiliary hydraulic operations.

Abstract: A liquid delivery system includes a reciprocating drive and a liquid cylinder comprising a liquid piston, operably driven by the reciprocating drive, to pump a liquid along a flow path to a liquid applicator. The liquid delivery system includes a coupler configured to couple the liquid piston to the reciprocating drive. The coupler includes a plurality of collar elements and a biasing member configured to apply a biasing force on the plurality of collar elements to retain the collar elements in a position that forms a collar that couples the liquid piston to the reciprocating drive.

Abstract: A locking unit with a hydraulically actuable piston, an electromagnet with a coil and an armature, at least one latching element, a coupling rod, and a magnetic element. The coupling rod connects the magnetic element to the armature or an armature rod which is attached thereto, and a prestressing element fixes the magnetic element in a guide tube radially. As a result, an advantageous position determination is made possible by way of sensing of a magnetic field which is generated by the magnetic element.

Abstract: A pneumatic actuator (4b), in particular for use in a pressure wave generator (1) comprises: a first piston surface (91) which acts counter to a gaseous working medium in a first volume (41), wherein a pressure in the first volume (41) effects an actuator force in a first direction upon the first piston surface (91); a second piston surface (92) which acts counter to the working medium in a second volume (42), wherein a pressure in the second volume (42) effects an actuator force in a second direction opposite to the first direction, upon the second piston surface (92); a throttle between the first volume (41) and the second volume (42); an inlet/outlet opening (45) of the first volume (41) for bringing the working medium into and discharging it out of, the first volume; wherein the first piston surface (91) is larger than the second piston surface (92).

Abstract: A connection switching device (45) connects a bottom-side oil chamber (15C) of a boom cylinder (15) and a bottom-side oil chamber (16C) of an arm cylinder (16) when a boom operating device (22A) instructs the contraction of the boom cylinder (15) and an arm operating device (21B) instructs the expansion of the arm cylinder (16). The connection switching device (45) connects the bottom-side oil chamber (15C) of the boom cylinder (15) and a rod-side oil chamber (16D) of the arm cylinder (16) when the boom operating device (22A) instructs the contraction of the boom cylinder (15) and the arm operating device (21B) instructs the contraction of the arm cylinder (16).

Abstract: A work machine includes a boom, a work tool configured to drive with respect to the boom, an actuator configured to drive the work tool, a sub-link attached to the boom, and a control section. The sub-link is configured to transmit driving force of the actuator to the work tool. The control section is configured to control the actuator based on a posture of the sub-link with respect to the boom. A method of controlling a work machine includes controlling an actuator based on a posture of a sub-link with respect to a boom, the sub-link being configured to transmit driving force of the actuator to a work tool configured to drive with respect to the boom.

Abstract: Provided is a construction machine configured such that a hydraulic actuator is driven by a hydraulic pump for a closed circuit, by which oil film breakage of the hydraulic pump for a closed circuit is prevented to improve the reliability and a high operation rate can be obtained. The construction machine includes a switching valve that is provided in a branch hydraulic line connecting one of suction/delivery ports of a closed circuit pump and a charge line to each other and is opened and closed according to a control signal from a controller. The controller is configured to, in a case where a state in which a delivery volume of the closed circuit pump is kept to zero continues for a predetermined time period or more, open the switching valve and keep the delivery volume of the closed circuit pump to a predetermined delivery volume or more, the predetermined delivery volume being greater than zero.

Abstract: Disclosed is a construction machine including: an engine generating power; a pump generating hydraulic pressure by receiving power generated from the engine; a main control valve receiving signal oil from the pump; a key switch capable of turning on and off power of an electronic unit; an engine control unit that maintains operation of the engine for a predetermined time and then stops operation of the engine when the key switch is switched from an on-state, during which power of the electronic unit may be turned on, to an off-state; and a pilot cut-off valve for opening and closing the signal oil according to the state of the key switch, and an accident caused by the engine control unit may be prevented by the construction machine.

Abstract: A device for maintaining a hydraulic supply of a utility vehicle includes a hydraulic pump, which is adjustable in terms of its delivery volume via a pressure control inlet, for feeding hydraulic fluid to a hydraulic circuit, a pressure accumulator that can be charged from the hydraulic circuit via a check valve, a pressure connection between the hydraulic circuit and the pressure control inlet of the hydraulic pump being producible via a sensor line by means of a charging valve, and a supply connection between the pressure accumulator and the hydraulic circuit being producible by means of a discharging valve, by virtue of the check valve being bypassed.