Abstract: An artificial muscle that includes a housing having an electrode region and an expandable fluid region and an electrode pair positioned in the electrode region, the electrode pair having a first electrode fixed to a first surface of the housing and a second electrode fixed to a second surface of the housing. The first and second electrodes each have two or more tab portions and two or more bridge portions. Each of the two or more bridge portions interconnects adjacent tab portions and at least one of the first and second electrodes includes a central opening positioned between the two or more tab portions and encircling the expandable fluid region. A dielectric fluid is housed within the housing and the electrode pair is actuatable between a non-actuated and an actuated state such that actuation from the non-actuated to actuated state directs the dielectric fluid into the expandable fluid region.

Abstract: A shovel includes a plurality of hydraulic actuators each configured to move in response to a movement command; a pressure sensor configured to detect a pressure of hydraulic oil in each of the hydraulic actuators; a meter-in valve in correspondence with each of the hydraulic actuators; a meter-out valve in correspondence with each of the hydraulic actuators; and a controller having a plurality of output characteristics set for each of the hydraulic actuators. The controller is configured to calculate a required flow rate corresponding to the movement command, based on an output characteristic corresponding to the movement command from among the plurality of output characteristics.

Abstract: The present disclosure provides an accumulator system that utilizes an ionic liquid for pressurizing gases. In particular, the accumulator system of the present disclosure avoids use of any internal mechanical parts, e.g., a bladder or a piston, thereby eliminating any potential for mechanical failure experienced by conventional accumulators.

Abstract: The invention relates to an axial piston machine in which pistons carry out a stroke movement in cylinders and in which the pistons have a seal ring receptacle for a seal ring. In order to improve robustness, wear resistance, friction and stick-slip behavior, according to the invention, the seal ring is spherical, wherein the curvature radius of the seal ring, which is spherical in regions, substantially corresponds to half the diameter of the cylinder inner wall.

Abstract: The present disclosure relates to a backhoe loader energy recovery and reuse system and a control method thereof, and a backhoe loader, wherein the system comprises: an actuator, configured to drive a working device to perform an action with hydraulic oil as a medium, and having a first cavity and a second cavity; a reversing valve, having a first working oil port communicated with the first cavity and a second working oil port communicated with the second cavity, the reversing valve being configured to reverse the actuator; a stabilizing valve group, having a first oil port, a second oil port, a third oil port and a fourth oil port, the first oil port and the second oil port being communicated with the first cavity and the second cavity, respectively, and the third oil port being communicated with an oil tank; and an energy storage part, communicated with the fourth oil port and configured to store hydraulic energy; wherein the first oil port and the third oil port have a first communication state therebetwe

Abstract: Disclosed are a hydraulic control system for boom floating of an excavator and a control method thereof. In the hydraulic circuit, a main pump supplies oil to the boom cylinder through a boom reversing valve, and two working ports of the boom reversing valve are connected to a rod cavity and a rodless cavity of the boom cylinder respectively. A rod cavity floating valve and a rodless cavity floating valve are connected to an oil circuit between the rod cavity of the boom cylinder and the boom reversing valve and an oil circuit between the rodless cavity of the boom cylinder and the boom reversing valve respectively. A pilot oil pump and a handle pilot valve are arranged on the pilot oil circuit, an oil inlet of the handle pilot valve is connected to the pilot oil pump.

Abstract: A hydraulic compressed air energy storage system includes air and liquid tanks, each of which includes interdependent volumes of liquid and air. Each tank includes dedicated passages through which incoming air may be fed, forcing outflow of liquid, or incoming liquid may be fed, forcing outflow of air. Compressed air tanks are connected to a first group of the air and liquid tanks. The system further includes a pump and a liquid turbine, the liquid turbine being electrically connected to a generator for generating electric power. During charging of the system, liquid is pumped through the first group of air and liquid tanks, and air is expelled from the first group of air and liquid tanks and compressed in the compressed air tanks. During discharging of the system, compressed air is released from the compressed air tanks, and said compressed air pumps liquid through the liquid turbine, thereby generating electricity.

Abstract: The present disclosure relates to a hydraulic circuit, comprising: a motion control valve including a valve spool and a hydraulic actuator for actuating the valve spool, and a hydraulic control device having an outlet fluidically connected to the hydraulic actuator, the hydraulic control device comprising a pressure-reducing valve or a pressure compensated flow control valve.

Abstract: A hydraulic drive system for a construction and/or thick matter pump system includes a first drive cylinder and a second drive cylinder, a first directional valve and a second directional valve, and a flushing hydraulic liquid device. The first directional valve is configured to connect the first drive cylinder to the second directional valve by way of a first switching position and to connect the second directional valve to the flushing hydraulic liquid device by way of a second switching position. The second directional valve is configured to connect the second drive cylinder to the first directional valve by way of a first switching position and to connect the first directional valve to the flushing hydraulic liquid device by way of a second switching position.

Abstract: A power system has a piston pump that is driven by high pressure gas from a high pressure gas source that alternatingly pressurizes a first gas chamber and a second gas chamber to drive a first piston and a second piston such that the piston pump pressurizes hydraulic fluid from a hydraulic reservoir into a hydraulic accumulator. The expanded high pressure gas from the piston pump is expelled to a low pressure gas outlet and the pressurized hydraulic fluid is used as a motive fluid to perform work.

Abstract: A pneumatic-hydraulic control device includes a piston seat mounted in a cylinder, a piston pin disposed in the piston seat and having an axial air channel, and an acting assembly. When the piston pin is closed, hydraulic oil cannot flow between the piston seat and the piston pin, so that the cylinder cannot be moved. When the piston pin is opened, hydraulic oil flows between the piston seat and the piston pin, so that the cylinder can be moved. The acting assembly includes a sleeve tube connected with the piston seat and an acting member connected with the piston pin and inserted in the sleeve tube to form an exhaust channel. The exhaust channel communicates with the axial air channel to eliminate negative pressure generated between the piston pin and the piston seat when the piston pin is pulled down, thereby reducing a pull-down resistance of the piston pin.

Abstract: Throttle ring for a piston compressor, the throttle ring comprising an axially running ring axis (Ar), an axial height (h), a radially inner running surface and a radially outer circumferential surface, and an upper flank and a lower flank, wherein the upper flank faces the compression space of the piston compressor when the throttle ring is in intended use. The running surface has at least one circumferential groove in the circulating direction, which is connected to the radially outer circumferential surface by at least one radial bore.

Abstract: The present invention relates to a mobile work machine, in particular to a wheeled loader, having a hydraulic circuit, having a pump for conveying a hydraulic medium through the hydraulic circuit, and having at least one control block having an inflow control edge and an outflow control edge for controlling the flow of the hydraulic medium, wherein the work machine has a working tool and a cylinder for actuating the working tool and wherein the cylinder has an outflow and in inflow for the hydraulic medium, and wherein the outflow is in fluid communication with the outflow control edge and the inflow is in fluid communication with the inflow control edge, and wherein the inflow control edge does not have any or has fewer fine control notches than the outflow control edge and thus works in a largely unrestricted manner, while the outflow control edge is equipped with one or more fine control notches so that with a pulling load at the working tool, the outflow control edge restricts the outflow amount through t

Abstract: An example system includes an electric motor (102); a pump (104) coupled to the electric motor; a hydraulic circuit (108) fluidly-coupled to the pump and configured to receive fluid flow from the pump; a hydraulic line (110) fluidly-coupled to the hydraulic circuit, wherein the hydraulic circuit is configured to provide a fluid signal to the hydraulic line, wherein the fluid signal is indicative of a fluid flow demand of the hydraulic circuit; a pressure sensor (112) mounted to the hydraulic line and configured to provide sensor information indicative of pressure level of fluid in the hydraulic line; and a controller (114) configured to control a speed of the electric motor to vary fluid flow rate provided by the pump to the hydraulic circuit to meet the fluid flow demand based on the pressure level indicated by the sensor information.

Abstract: This hydraulic pump system includes: a hydraulic pump having a discharge flow rate that is changeable; a regulator device that adjusts the discharge flow rate of the hydraulic pump; an operation device including an operation tool; a lock switching input unit that unlocks the operation tool; an unloader valve that adjusts a discharge pressure of the hydraulic pump by changing the opening area of the unloader valve; and a control device that controls movement of the unloader valve. When a predetermined actuation condition is satisfied, the control device causes the unloader valve to reduce the opening area to increase the discharge pressure of the hydraulic pump. The regulator device increases the discharge flow rate after the control device causes an increase in the discharge pressure of the hydraulic pump. The actuation condition includes a condition that the lock switching input unit has unlocked the operation tool.

Abstract: A valve plate of a hydraulic pump/motor, includes a high pressure-side port and a low pressure-side port, a first oil groove provided to be endless in an outer peripheral part of the high and low pressure-side ports, and a plurality of second oil grooves. Further, a plurality of pad oil grooves communicating with the first oil groove and opened toward the end face of the cylinder block is provided in an outer peripheral portion of the high pressure-side port, at least in a portion being on a downstream side of the relative rotation, in a pad region contacting the end face of the cylinder block, and the plurality of pad oil grooves is provided such that a proportion of an opening area to the end face of the cylinder block is larger on the downstream side than on an upstream side of the relative rotation.

Abstract: A transfer-of-mass system for increasing rotational energy output thereof includes a sealed container having a central axis and an outer wall radially spaced apart from the central axis. A liquid partially fills the container. A motor causes the container to rotate about its central axis at a speed of rotation such that the liquid is acted upon by centrifugal forces to move it to the container's outer wall. Energy is applied to the liquid to cause at least a portion of the liquid at the container's outer wall to move towards the container's central axis wherein the container rotates faster than the speed of rotation caused by the motor.

Abstract: In accordance with at least one aspect of this disclosure, a system (e.g., for aircraft systems) includes an actuator cylinder. The actuator cylinder comprises, a composite cylinder body, the composite cylinder body being axi-symmetric across at least a longitudinal axis. In embodiments, the composite cylinder body can include, a first plurality of plies laid in a first direction relative to the longitudinal axis and second plurality of plies laid in a second direction relative to the longitudinal axis different from the first direction to form a hollow chamber. The actuator cylinder can include a first metallic reinforcing ring and a second metallic reinforcing ring disposed at respective axial ends of the cylinder body configured to anchor the first plurality of plies and provide an axial reaction under axial stress and configured to provide load transfer from the cylinder body to one or more adjacent actuator components.

Abstract: A chamber for pumping relatively small volumes of fluid is provided. The chamber includes a plug moveable between a retracted position and an extended position. When the plug is in the retracted position, the plug may be positioned and located toward a first end of the chamber such that fluid may enter into the chamber through an inlet. Once the fluid is received into the chamber, the plug may be moved toward the extended position. As the plug moves toward the extended position, the plug may be pressed into a variable volume plate. As the plug is pressed into the variable volume plate, the plug may deform and enter into a cavity. When the plug enters the cavity, the plug may push fluid out from the cavity. Thus, a known volume of fluid may exit the chamber when the plug is moved from the retracted position to the extended position.

Abstract: Venting a cylinder of a piston-cylinder unit of a power brake pressure generator of a hydraulic power brake system for a motor vehicle. A piston in the cylinder is displaced from a forward-displaced position back into a home position and subsequently forward again. When the piston is displaced back, a connection valve is closed so that the piston sucks brake fluid from a brake fluid container, the brake fluid flowing over a lip seal acting in the manner of a pressure relief valve as the first piston seal. During the forward stroke, the piston pushes brake fluid through the then open connection valve into the brake fluid container. Any air contained in the cylinder is pushed with the brake fluid from the cylinder and separates from the brake fluid in the brake fluid container.