Abstract: The multi-temperature double-acting piston includes a peripheral sealing ring, a lower hot crown and/or an upper hot crown, and moves in translation in a cold cylinder of a heat engine which includes a lower cylinder head and an upper cylinder head, the piston including a central piston pin the lower piston rod of which passes through the lower cylinder head so as to be connected to a power transmission housed in a transmission casing, and the upper piston rod of which passes through the upper cylinder head so as to open out into a piston cooling and lubricating chamber, a lubricating-cooling gallery provided in the pin putting the chamber in communication with the casing via an internal piston volume.

Abstract: An intermittent flushing plunger packing assembly is described herein. The packing assembly includes a plurality of annular seals disposed about the plunger configured to reciprocate along a linear axis within the fluid bore of the pump, and an annular packing nut disposed circumferentially about the plunger and configured to retain the plurality of annular seals and adjust a combined height of the plurality of annular seals. A selected one of the plurality of annular seals proximate to the fluid cylinder of the pump has a flushing fluid chamber in fluid communication with a flushing fluid port coupled to a first one-way check valve allowing a pressurized flushing fluid to be introduced and retained within the flushing fluid chamber and creating a fluid barrier to prevent frac fluid in the fluid cylinder from bypassing the annular seals.

Abstract: A displacement pump is configured to mount to a drive housing. A reciprocating drive is connectable to a pump rod of the displacement pump and includes a connecting rod and a drive link that receives a head of the pump rod. A flange projects from a pump body of the pump and a ring projects from the pump body of the pump. A portion of the drive housing is received in a gap between the flange and the ring.

Abstract: A working cylinder has a cylinder tube has closure parts arranged at tube ends. The cylinder tube and the closure parts define a cylinder interior. The cylinder has a coupling section that has one of the closure parts, a cylinder tube end and a hollow adapter body. The closure part has an external thread and the adapter body has an internal thread that define a common threaded section constructed to releasably couple the closure part and the adapter body. The cylinder tube end is connected to the adapter body on a cylinder tube side thereof by a ring weld seam. The weld seam defines a sealing plane sealed with respect to a pressure media. The piston unit defines at least one working chamber inside the cylinder.

Abstract: A system for controlling a hydraulic supply on a mobile machine comprises electronic load sensing and is configured to predictively increase the pump supply pressure PSP following a determination that a hydraulic consumer is about to be actuated. The pump supply is increased irrespective of the reported hydraulic load at the time to meet a predicted hydraulic demand of consumer. The control system may revert to a load-sensing-based control of the pump supply after a given time period or in dependence on a predefined operational parameter being met. A corresponding method of controlling a hydraulic system on a mobile machine is also disclosed.

Abstract: A hydraulic control system for linear actuation that includes an electric motor connected to a hydraulic pump and a hydraulic cylinder connected to the pump by a first flow line. A pressure transducer, a pressure control valve, and a check valve are connected to the first flow line between the pump and the cylinder and a tank is connected to the pump by a second flow line and the cylinder by a return line. A control valve is connected between the first flow line and the return line.

Abstract: A supply device for an apparatus includes: a first flow path through which a fluid can flow; a first consumer which is arranged in the first flow path and can be supplied with the fluid via the first flow path; a pump which is arranged in the first flow path and by which the fluid can be pumped out of a reservoir through the first flow path; a throttle which is arranged in the first flow path upstream of the first consumer and downstream of the pump; a second flow path through which the fluid can flow and which is fluidically connected to the first flow path at a first connection point located in the first flow path upstream of the throttle and downstream of the pump; and a second consumer which is arranged in the second flow path and can be supplied with the fluid via the second flow path.

Abstract: A linear drive assembly configured for use within a power end assembly. The linear drive assembly is configured to interconnect a crankshaft and a pony rod and comprises a crosshead assembly attached to a connecting rod assembly. In one or more embodiments disclosed herein, the connecting rod assembly is configured to attach to opposite sides of the crosshead assembly so that no portion of the connecting rod assembly is disposed within an interior of a crosshead included in the crosshead assembly.

Abstract: A control system for a work machine includes a plurality of hydraulic pumps that discharge hydraulic oil, a hydraulic cylinder that moves a working equipment element, a plurality of flow rate control valves that are respectively connected to the hydraulic pumps and adjust a flow rate of the hydraulic oil supplied to the hydraulic cylinder, a plurality of supply flow paths respectively connected to the of flow rate control valves, a meter-in flow path that connects a collective part of the supply flow paths and an inlet of the hydraulic oil in the hydraulic cylinder, a plurality of discharge flow paths respectively connected to the flow rate control valves, a meter-out flow path that connects a collective part of the discharge flow paths and an outlet of the hydraulic oil in the hydraulic cylinder, and a throttle disposed in the meter-out flow path.

Abstract: In a pressure compensation valve, a spool portion of a valve body is provided with a throttle passage that constantly communicates with a pump port. A case is provided with supply pressure communication passages to block space between the throttle passage and a load pressure chamber when a poppet portion closes space between the pump port and a cylinder port by biasing force of a load pressure spring, and that, meanwhile, communicate between the throttle passage and the load pressure chamber via a throttle hole when the spool portion moves in an opening direction by a predetermined stroke. A lead-out pressure chamber that presses the poppet portion in a closing direction in a case where an internal pressure increases is provided between the poppet portion and the case, and a lead-out pressure passage that constantly communicates with the cylinder port is connected to the lead-out pressure chamber.

Abstract: A method includes using two parallel electrohydraulic servo valves EHSVs with a single transfer valve to move an actuator during a normal operation mode. The method includes upon failure of one of the EHSVs, using the single transfer valve to disconnect a non-operational one of the EHSVs and continuing to move the actuator with a functional one of the EHSVs in a backup mode.

Abstract: This disclosure is applicable to intelligent automobiles, new energy automobiles, conventional automobiles, or the like. In an example embodiment, a fluid outlet pipe of a first hydraulic chamber is configured in segments on a push rod support portion and a push rod. When a piston is located at an inner stop point of a piston stroke, a first hydraulic adjustment port located on the push rod support portion communicates with a second hydraulic adjustment port located on the push rod, and when the piston is located at a position other than the inner stop point in the piston stroke, the first hydraulic adjustment port does not communicate with the second hydraulic adjustment port.

Abstract: A hydraulic system comprises: a hydraulic pump that includes an swash plate; an swash plate angle sensor for measuring the angle of the swash plate; an swash plate driving piston for moving the swash plate of the hydraulic pump in response to changes in pressure applied to a large diameter section; an swash plate control hydraulic line for supplying the large diameter section with a portion of the hydraulic oil discharged by the hydraulic pump; a control valve that controls the flow rate of the hydraulic oil that is following into and out of the large diameter section; an electro-proportional pressure reducing valve for producing pilot pressure that is to be transmitted to one side of the control valve; and a control device for controlling the electro-proportional pressure reducing valve according to an operation signal of an operation device and the angle information from the swash plate angle sensor.

Abstract: A cylinder positioning system (1) comprising a control unit for a pneumatically driven cylinder (14) in a cylinder chamber is provided. The control unit comprising a controller configured to control a set of drive units of the cylinder positioning system. Each drive unit emits a drive current to a respective electromagnetic direct acting valve (9,10, 11, 12) of the cylinder positioning system. Each respective electromagnetic direct acting valve has a closing/opening time of less than 2 ms. The control unit is configured to receive a set position for the cylinder and an actual position for the cylinder, to compare the set position of the cylinder with the actual position of the cylinder and to emit control signals to the drive units to move the cylinder from the actual position towards the set position.

Abstract: A hydraulic system for a working machine includes a variable displacement hydraulic pump, a plurality of hydraulic actuators, and a plurality of control valves. Each of the control valves includes an input port, an output port, and a flowrate reduction section. At least one of the control valves includes a flowrate increase section. The hydraulic actuators are a boom cylinder, a working tool cylinder, and an auxiliary actuator. The control valves are a boom control valve for controlling the boom cylinder, a working tool control valve for controlling the working tool cylinder, and a first auxiliary control valve for controlling the auxiliary actuator. The boom control valve and the working tool control valve each include the flowrate reduction section, and the first auxiliary control valve includes the flowrate reduction section and the flowrate increase section.

Abstract: A pivot joint for a robot, including a double-acting pneumatic pivot actuator, which has a first working chamber with a first working port and a second working chamber with a second working port, and further including a valve arrangement having a first valve group for a selective connection of the first working port to one of a pressurization port and an exhaust port, and having a second valve group for a selective connection of the second working port to one of the pressurization port and the exhaust port. The valve arrangement includes a safety valve which is connected to the first working port and to the second working port and which is configured for blocking a connection between the first working port and the second working port in a blocking position and for releasing the connection between the first working port and the second working port in a release position.

Abstract: Disclosed here is a system and method to control multiple eversion-based actuators using a single motor, or no motor, thereby reducing the size and cost of the multiple eversion-based actuators. An activation mechanism can include a motor rotating in an expansion direction, rotating shaft, clutch, brake, pressure source under high pressure, and/or valve. The activation mechanism can cause the actuators including a wound reel of material to unwind and lengthen. A retraction mechanism can include a motor rotating in a contraction direction opposite the expansion direction, rotating shaft, clutch, pressure source having low pressure, valve associated with the pressure source, and/or the passive retraction system. The retraction mechanism can cause the actuators to rewind and shorten.

Abstract: A valve arrangement structure of a control valve unit includes a control valve body to which oil is supplied from a main pump. The valve arrangement structure includes a pressure regulator valve that is arranged in the control valve body and regulates a pressure of discharged oil from the main pump to a line pressure, a pressure control valve that is arranged in the control valve body and regulates the pressure of the oil to a required pressure with the line pressure as a source pressure, and a first oil passage that is provided in the control valve body and connects the main pump and the pressure regulator valve. The pressure control valve is arranged on a second oil passage branched from the first oil passage.

Abstract: A hydraulic machine includes an actuator, a tank, a directional control valve disposed between the actuator and the tank, and an adjustable return check valve disposed between the directional control valve and the tank. The directional control valve includes an attachment actuator directional control valve disposed between an attachment actuator of the actuator and the tank and a swing actuator directional control valve disposed between a swing actuator of the actuator and the tank. The adjustable return check valve allows fluid to flow from the attachment actuator directional control valve toward the tank while applying the low back pressure but blocks a flow, and allows fluid to flow from the swing actuator directional control valve toward the tank while applying the high back pressure but blocks a reverse flow.

Abstract: A working machine includes a machine body, a left traveling device located left on the machine body, a right traveling device located right on the machine body, and a controller configured or programmed to perform automatic deceleration to automatically reduce a first rotation speed of a left traveling motor and a second rotation speed of a right traveling motor by shifting a speed stage of each of the left and right traveling motors from a second speed stage to a first speed stage that is lower than the second speed stage. The controller is configured or programmed to: not perform the automatic deceleration when the first rotation speed or the second rotation speed is equal to or higher than a predetermined rotation speed; and perform the automatic deceleration when the first rotation speed and the second rotation speed are less than the predetermined rotation speed.