A cylinder includes a cylinder tube, a first closure part, a second closure part, and a piston unit. The cylinder tube has a first tube end and a second tube end. The tube and end closure parts define a cylinder interior. The piston unit defines at least one working space in the cylinder interior. The first closure part is connected to the tube by a first peripheral laser ring weld and the second closure part is connected to the tube by a second peripheral laser ring weld. The laser ring welds each define a fluid-tight sealing plane. A peripheral sealing ring is located between each closure part and a tube inner wall at an axial distance from the associated laser ring weld seam. The peripheral sealing ring defines a pressure-separated ring section between the peripheral sealing ring and the associated laser ring weld seam.

A modular electrohydraulic actuator including an electric motor, a hydraulic pump driven by the electric motor, and a hydraulic actuator in fluid communication with the hydraulic pump. The hydraulic actuator includes a hydraulic cylinder supporting a pressure sleeve in which a piston and rod is adapted for reciprocating motion in response to a supply of pressurized fluid to a first side or a second side of the piston, wherein at least one of the electric motor, hydraulic pump, hydraulic cylinder, piston, piston rod or the pressure sleeve supported in the hydraulic cylinder is selectively removable and replaceable with a different component to vary at least one performance characteristic of the electrohydraulic actuator.

A telescopic device having a housing and a rod is slidably mounted within a bore of the housing. First and second bearings provide sliding engagement between the rod and the housing. The first bearing is mounted relatively close to the open end of the bore and the second bearing is mounted relatively far from the open end of the bore relative to the first bearing. The second bearing is annular in shape with a central axis, the bearing has a radially outer mounting surface of arcuate cross-section and a radially inner bearing surface for sliding engagement with an outer surface of the rod and wherein the inner sidewall is provided with an annular groove having a second mounting surface of arcuate cross-section to house and retain the second bearing.

In a fluid pressure cylinder, a first positioning ring is provided detachably on a first annular projection of a head cover, and a second positioning ring is provided detachably on a second annular projection of a rod cover. Further, a structure is provided in which opposite ends of a cylinder tube are inserted over and capable of being retained on outer circumferential sides of the first and second positioning rings. As a result, by preparing a new cylinder tube having a different diameter, and new first and second positioning rings, and mounting the new cylinder tube through the new first and second positioning rings, which are installed on the first and second annular projections, a fluid pressure cylinder having a different bore diameter can be obtained.

A rotary actuator where a thrust bearing ring is positioned at an inside of a tube assembly accommodating oil, thereby reducing abrasion and damage caused by rolling friction and improving rotary power of an axle load by increasing hydraulic pressure of a piston. The rotary actuator includes the tube assembly, a piston, an axle load assembly, and a thrust bearing ring. The tube assembly is provided with a tube spiral portion where a spiral is formed at an inner circumference surface, and is formed of a first passage where oil flows into and out and a second passage spaced apart from the first passage by a fixed distance.

A gas pressure actuator includes a launcher, a gas generator that is disposed at a first axial end of the launcher, a rocket part placed inside the launcher, an end pad and a sealing gasket respectively disposed at a second axial end of the launcher, and a gasket holder supporting the gasket. The rocket part includes a first portion disposed at a location corresponding to the first axial end and a second portion that has a diameter less than that of the first portion and that ranges from the first portion toward the second axial end. The end pad includes a position determination part that determines positioning of the rocket part and restricts the rocket part from being displaced in a direction away from the first axial end. The gasket holder may be pressed by the first portion when the rocket part protrudes from the launcher and plastically deformed.

Disclosed are seal arrangements in a hydraulic device. The seal arrangement includes a seal channel defining a loop. A seal is seated within the seal channel. A coolant flow passage has a first part intersecting with the seal channel at a first point and a second part intersecting with the seal channel at a second point. The first part of the coolant flow passage is configured to provide hydraulic fluid to the seal channel such that, at the first point, a first portion of the hydraulic fluid flows in a first direction around the loop and a second portion of the hydraulic fluid flows in a second direction opposite to the first direction around the loop. At the second point, the first portion of hydraulic fluid and the second portion of hydraulic fluid are configured to flow into the second part of the coolant flow passage.

A cylinder has first and second coupling partners. The first coupling partner is a cylindrical tube. The second coupling partner is a closing element. One coupling partner is inserted axially into the other coupling partner. Each of the coupling partners has an annular groove. The groove of the inserted coupling partner is an external groove. The groove of the remaining coupling partner is an internal groove and the grooves of the coupling partners lie opposite one another. The working cylinder includes a spring-loaded coupling ring, and which when deformed in a tensioning direction, can be fully accommodated by the groove of one coupling partner and which, when deformed in the release direction, engages in the grooves of both coupling partners. The inserted coupling partner is oversized in relation to the remaining coupling partner and provides a additional frictional connection.

A linear telescopic actuator (1) that comprises a cylinder (2), a sliding part (3), a spring seat (4) and a first compression spring (5) capable of resiliently opposing the sliding part (3) approaching the spring seat (4). The spring seat (4) presents an outer annular groove (6) and the cylinder (2) includes an inner annular groove (7). The actuator (1) also presents a blocking part (8), the actuator (1) being adapted to adopt selectively an assembled configuration and a disassembled configuration. The blocking part (8) in the assembled configuration is engaged inside the inner and outer annular grooves (6, 7). The blocking part (8) in the disassembled configuration being disengaged from one of the grooves so as to allow spring seat (4) to slide in the cylinder (2).

A piston rod assembly for a pressurized fluid-powered actuator is provided. The assembly includes a piston rod having a fluid flow passage extending along an interior thereof, and a cap secured to the piston rod at a position along the fluid flow passage. Sealing means is positioned between the piston rod and the cap so as to provide a fluid-tight seal between the piston rod and the cap.