Abstract: A primary piston assembly for a master brake cylinder of a braking system of a vehicle, including a first primary piston component having a first piston element to which a driver braking force is transmittable in such a way that a pressure chamber volume of a pressure chamber of a master brake cylinder of the braking system which is fillable with liquid is reducible by moving the first piston element with the aid of the driver braking force, and a second primary piston component having a second piston element to which the first braking assisting force is transmittable in such a way that the pressure chamber volume of the pressure chamber is reducible by moving the second piston element with the aid of the first braking assisting force.

Abstract: In one aspect, a system for controlling the supply of hydraulic fluid to an implement of a work vehicle may generally include a pump, a control valve coupled to the pump and first and second fluid lines provided in flow communication with output ports of the control valve. The system may also include a pressure control valve provided in flow communication with the second fluid line that is configured to regulate a fluid pressure of the hydraulic fluid being supplied to a hydraulic cylinder of the implement. Additionally, the system may include a bypass fluid line configured to provide a flow path for hydraulic fluid between the pump and the second fluid line that is independent of the control valve and a load sensing line configured to provide an indication of the fluid pressure of the hydraulic fluid being supplied to the hydraulic cylinder.

Abstract: A brake booster for a vehicle brake system includes a brake force transmitting element, a booster force transmitting element, a first rotation sensor, and a second rotation sensor. The brake force transmitting element is moveable in an axial direction for transmitting a pedal brake force from a brake pedal to a primary brake cylinder. The booster force transmitting element is moveable in the axial direction for transmitting a booster brake force to the primary brake cylinder. The first rotation sensor is kinematically coupled with the brake force transmitting element via a motion converting mechanism for measuring the axial position of the brake force transmitting element. The second rotation sensor is kinematically coupled with the booster force transmitting element for measuring the axial position of the booster force transmitting element. The measurements of the first and second rotation sensors are used for controlling the generation of the booster brake force.

Abstract: An element is provided to maintain a clearance gap between a piston and a cylinder wall. In some embodiments, an element is included that is capable of spatial change. In some embodiments, the element is a component such as a clearance ring, a surface bearing, or a segment of a clearance ring or surface bearing. A clearance gap may be maintained by inward and outward motion of the component with respect to a piston assembly and a cylinder wall, where the motion is determined by a balance of forces acting on the component. In some embodiments, an inward force generated by an external gas pressure source is balanced by an outward preload force generated by, for example, a pneumatic piston. In some embodiments, a clearance gap is maintained based on in part on the ratio of inner to outer surface areas of a clearance ring.

Abstract: The present invention relates to a system preventing the pressured oil leakage in a cylinder line enabling very low leakage rates without using the valve or the system, or without reducing the diametrical space between the housing and spool.

Abstract: A brake apparatus improved in mountability on a vehicle is provided. The apparatus includes a master cylinder 4 that generates hydraulic brake pressure by a driver's brake operation, and a stroke simulator 5 that creates an artificial operation reaction force of a brake operation member when the brake fluid flown out of the master cylinder 4 enters the stroke simulator 5. The master cylinder 4 and the stroke simulator 5 are integrally arranged to overlap each other in a perpendicular direction (as viewed from the perpendicular direction) when installed in the vehicle.

Abstract: To keep operability of a hydraulic actuator excellent even in a state pressure has been sufficiently accumulated in a pressure accumulator. In a hydraulic driving device of a work machine including a hydraulic actuator, a tank, a flow control valve, and a pressure accumulator, there are further provided with a first pressure compensation valve that is for controlling difference between front and back pressures of the flow control valve constant and a second pressure compensation valve that is arranged between the pressure accumulator and the tank and is for controlling difference between front and back pressures of the flow control valve and the first pressure compensation valve constant.

Abstract: A valve housing includes a cylindrical valve bore with a high pressure inlet, a low pressure inlet and a discharge outlet. A first flushing valve spool is arranged elastically pre-stressed within the valve bore for enabling a fluid connection between the low pressure inlet and the discharge outlet. A shuttle valve spool is arranged elastically pre-stressed within the valve bore for enabling the fluid connection between the low pressure inlet and the discharge outlet. The first flushing valve spool is moveable into an open position if the fluid pressure at the low pressure inlet exceeds a first threshold value, and the shuttle valve spool is moveable into an open position for connecting the low pressure inlet with the discharge outlet, if the pressure difference between the high pressure inlet and the low pressure inlet exceeds a second threshold value.

Abstract: A hydraulic excavator drive system includes: a cylinder that drives a moving part that is an arm or a bucket. Hydraulic oil is supplied from a hydraulic pump to the cylinder via a control valve. A bypass line branches off from a rod-side supply/discharge line. The bypass line is blocked and opened by a restrictor. The restrictor is controlled by a controller such that, when the hydraulic oil is supplied to the cylinder through a head-side supply/discharge line, the restrictor blocks the bypass line if a pressure detected by a load detector is lower than a predetermined value, and opens the bypass line if the pressure detected by the load detector is higher than or equal to the predetermined value.

Abstract: An apparatus (10) blocks and adjusts a pressure for a hydraulically controllable actuator (12), particularly a lifting unit (16) of a machine (18). The apparatus (10) allows a working chamber (20, 22) to be selectively connected to a pressure supply unit (94) having a storage device (34) or to a discharge end (66), in particular a reservoir end, by a valve unit (38). In a controlling position of the valve unit (38), when the storage pressure in the storage device (34) is greater than the working pressure in the working chamber (20) of the actuator (12), the storage pressure is relieved in the direction of the discharge end (66) until the working pressure has been reached.

Abstract: A working machine includes a machine body, an operation fluid tank mounted on the machine body, a hydraulic device to be operated by an operation fluid supplied from the operation fluid tank. A valve unit includes a plurality of control valves to control the hydraulic device. The control valves are arranged along a horizontal direction. A switch valve is to be connected to the control valves. A first tube member includes a first fluid tube to connect the control valve and the switch valve to each other and supports the switch valve above the control valve.

Abstract: Disclosed are a device and a method for controlling a hydraulic pump in a construction machine, the method including: checking whether a dynamic characteristic of an engine deviates from a predetermined permissible range when a load is applied to the hydraulic pump and a pump load reaches pump torque required by the hydraulic pump; when the dynamic characteristic of the engine deviates from the predetermined permissible range, applying a pump load to the hydraulic pump so as to increase the pump torque to predetermined torque with a predetermined change rate; collecting information which is generated when the pump load is applied; generating a new torque change rate map by generating a torque change rate for each load section based on the information collected in the information collecting step; and updating an existing torque change rate map to the new torque change rate map generated in the map data generating step.

Abstract: A turning control apparatus includes a turning body and a hydraulic motor to turn the turning body. A high-pressure relief circuit relieves hydraulic pressure of a first hydraulic line at a first relief pressure, the first hydraulic line supplying an operating oil to drive the hydraulic motor. A hunting reduction circuit relieves a hydraulic pressure of a second hydraulic line at a pressure lower than the first relief pressure, the second hydraulic line being connected to a deceleration-side hydraulic port from which the operating oil is discharged when the hydraulic motor is being driven. The hunting reduction circuit connected to the deceleration-side hydraulic port is caused to open before an operation lever to operate turning of the turning body returns to a neutral position.

Abstract: An optional-attachment-operating direction switching valve is provided in a part of an unloading passage which part is on the upstream of an arm-operating direction switching valve and a bucket-operating direction switching valve.

Abstract: A compressor of the present invention comprises a crankshaft, a first compression part, and a second compression part for further compressing a gas discharged from the first compression part. The first compression part comprises a first reciprocating motion conversion part, a first pressing part, and a first cylinder body comprising a plurality of cylinder components, while the second compression part comprises a second reciprocating motion conversion part, a second pressing part, and a second cylinder body comprising a plurality of cylinder components. The number of the cylinder components of the second cylinder body is smaller than that of the cylinder components of the first cylinder body.

Abstract: A magnet-type rodless cylinder (1) is provided with a guide mechanism having an outer rolling groove (26), an inner rolling groove (29), a cylinder body (32), a pair of connection paths (34) for connecting an area between the outer rolling groove and the inner rolling groove with the cylinder body, and a plurality of steel balls (36) that can roll within an endless circuit (35) formed of the cylinder body, the connection paths and the area between the outer rolling groove and the inner rolling groove, wherein the connection paths (34) are formed at a pair of inner members, i.e. return caps (33), disposed on the inner sides of metal end plates (12) that are attached to the front and rear ends in the sliding direction of a sliding body (4).

Abstract: A pneumatic system for operating a drive for a windshield wiper for a rail vehicle, wherein the windshield wiper drive has a piston guide device that has a first connection and a second connection opposite the first connection. At least one piston in the piston guide device carries out linear movements in opposite directions along the main direction of extension of the piston guide device to bring about an alternating rotational movement of the wiper shaft. The pneumatic system has a supply connection for a compressed air supply, wherein the supply connection is connected to the first connection via a first normal operation connection line and a first emergency operation connection line arranged parallel thereto and to the second connection via a second normal operation connection line and a second emergency operation connection line arranged parallel thereto.

Abstract: A hydraulic system includes an engine; at least one hydraulic pump operatively coupled to the engine for transfer of mechanical power therebetween; and a controller operatively coupled to the engine and the at least one hydraulic pump. The controller is configured to determine a lug speed error as a difference between a target lug speed value and a speed of the engine, set at least one closed-loop gain to zero when the speed of the engine is greater than or equal to the target lug speed value, set the at least one closed-loop gain to a non-zero value when the speed of the engine is less than the target lug speed value, generate a pump control signal by scaling the lug speed error by the at least one closed-loop gain.

Abstract: A driver brake force simulator is provided for a braking system of a vehicle, including at least one spring, and a displaceable piston which delimits a pressure chamber formed in the driver brake force simulator and which is movable from its starting position, against an elastic force of the at least one spring, by a predefined maximum displacement travel in a first direction in such a way that a volume of the pressure chamber which is fillable with brake fluid is increasable. The driver brake force simulator includes at least multiple disk springs as the at least one spring. Moreover, a manufacturing method is provided for a driver brake force simulator for a braking system of a vehicle by supporting a displaceable piston of the driver brake force simulator with the aid of at least one spring. The displaceable piston is supported by at least multiple disk springs as the at least one spring.

Abstract: A construction machine includes: a lower traveling body; an upper slewing body; a front attachment; a plurality of hydraulic actuators including traveling motors; hydraulic pumps; a plurality of control valves for the hydraulic actuators; a plurality of operation units for the control valves; traveling operation detectors that detect operations for the operation units for the traveling motors of the operation units; a back-pressure compensation valve generating back pressure in a return pipe line connecting each of the control valves and a tank and having a setting pressure switchable between low and high pressure setting values; and a back-pressure control section performing a back-pressure lowering control of making the setting pressure of the back-pressure compensation valve be the low pressure setting value when traveling operation amounts in the traveling operation units are large.