Elastomeric actuators and methods of making the same are provided herein. In some examples, an actuator includes a body comprising a plurality of pairs of frustums, wherein the body is configured to receive a fluid to extend the actuator and to remove the fluid to contract the actuator. In some examples, each pair of frustums includes two thin frustum shells sharing a common base circle diameter.

A hydraulic actuator includes a body defining a bore having a first end surface, a second end surface, and a bore surface, and a piston slidable in the bore. The piston, bore surface and first end surface define a first chamber, and the piston, bore surface and second end surface define a second chamber. The body also defines an accumulator chamber and a fluid passage between the first chamber and the accumulator chamber. An accumulator is received in the accumulator chamber and a valve selectably opens and closes the fluid passage.

A gas cylinder includes supply passages for supplying, to an accommodation chamber, a part of gas supplied to a second port. When the pressure in a first pressure chamber is equal to or lower than a prescribed pressure, a valve element closes a discharge flow passage by the biasing force of a spring member and the pressure in the accommodation chamber. When the pressure in the first pressure chamber exceeds the prescribed pressure, the valve element is moved by the pressure in the first pressure chamber, against the biasing force and the pressure in the accommodation chamber, to thereby open the discharge flow passage.

A cover system for a damper includes an outer tube and a piston rod extending from an end of the outer tube. The cover system also includes a dust tube disposed around a portion of the outer tube. The dust tube includes a first end located proximal to the end of the outer tube and a second end opposite to the first end. The dust tube at least partially encloses the piston rod. The cover system further includes a cap connected to the outer tube. The cap is adapted to at least partially cover the first end of the dust tube.

A fluid leakage detection system has a detection space to which working oil leaked out through a rod seal is guided; the rod seal being configured to seal an annular gap between a piston rod and a cylinder head; a sensor unit configured to detect pressure in the detection space; and a controller configured to acquire detected result from the sensor unit, wherein the controller has: a calculation unit configured to calculate a pressure parameter representing a pressure fluctuation in the detection space; a determination unit configured to determine occurrence of leakage of the working oil based on the pressure parameter; and the pressure parameter includes an upper limit value and a lower limit value of the pressure fluctuation obtained from the detected result detected by the sensor unit within a predetermined detection period.

A bale chamber includes: movable density doors; at least one fluid cylinder including a fluid chamber, a piston separating the fluid chamber into a piston side and a rod side, a cylinder rod coupled to the piston on the rod side and configured to move at least one of the density doors, a piston fluid port, and a rod fluid port; and a fluid supply circuit fluidly coupled to the fluid chamber and configured to supply working fluid to the fluid chamber, the fluid supply circuit including a fluid supply controller that is selectively switchable to a first fluid supply mode and a second fluid supply mode, the fluid supply circuit being configured to supply working fluid to only the piston side when in the first fluid supply mode and to supply working fluid to both the piston side and the rod side when in the second fluid supply mode.

A hydraulic cylinder is provided with a cylinder tube, a piston unit, and a piston rod. The piston unit has a piston body; packing mounted on the piston body; a holding member mounted on the piston body; and a magnet held by a magnet holding part of the holding member. The magnet holding part has a notch that is open on the outer circumferential surface of the holding member.

A cylinder device includes: a first piston (8) inserted in a first cylinder hole (4) so as to be movable in an axial direction, a piston rod (7) being hermetically inserted in the first piston (8), the first piston (8) being fixed to the piston rod (7); a second piston (10, 37) inserted in a second cylinder hole (5) so as to be movable in the axial direction, the piston rod (7) being inserted in the second piston (10, 37); and a partition wall (13) dividing a cylinder hole (6) into the first cylinder hole (4) and the second cylinder hole (5), the partition wall (13) being movable in the axial direction.

A screw pump comprises a body which has a cylindrical duct formed therein. A screw shaft is located in the cylindrical duct and is arranged to transport liquid between an inlet and an outlet of the screw pump. The screw shaft has a screw thread which defines a helical liquid path within the cylindrical duct. The body of the screw pump includes a groove extending along an inside surface of the cylindrical duct, the groove defining, in part, a ball-passage which extends alongside the screw shaft and intersects with the helical liquid path. The ball-passage contains a plurality of balls which are guided along the ball-passage by the screw thread when the screw shaft rotates relative to the body.

A plurality of detection valves (12 and 13) are provided to a housing (1), and at least one air passage (14 and 15), which communicatively connects the detection valves (12 and 13) to each other in series, are provided to the housing (1). One or some of the detection valves (12 and 13) are each configured as a throttle detection valve (13) including a throttle passage (56a).