Abstract: A cylinder apparatus includes a piston and a cylinder tube including a first end and a second end. The cylinder tube is formed to include a central bore extending from the first end to the second end for receiving the piston therein and a second bore extending from the first end to the second end spaced apart from the central bore. The cylinder apparatus also includes a first end cap coupled to the first end of the tube and a second end cap coupled to the second end of the tube. The second end cap is formed to include a first port in communication with the central bore of the tube and a second port in communication with the second bore. First end cap and second end cap have similar configurations and use substantially identical seals. Therefore, the semi-finished parts of the present invention have substantially identical configurations, regardless of the specific embodiment selected for a particular use.

Abstract: A rotary actuator for converting reciprocating motion to rotary motion including a housing having spaced-apart end plates connected by guide rods. A bellows is provided having opposite sides one of which is connected to one of the end plates, the bellows being adapted to be connected to a source of fluid under pressure so that the bellows expands from a collapsed to an expanded position. A guide plate is provided movably mounted on the guide rods with the other bellows side being connected thereto. A rack and pinion assembly is provided mounted on the other end plate, the rack being connected to the guide plate so that expansion and contraction of the bellows causes linear movement of the rack thereby imparting rotary movement to the pinion. A spring acts between the guide plate and the other end plate thus resisting expansion of the bellows and returning it to the collapsed position upon the release of fluid pressure.

Abstract: A fluid power system including a fluid power cylinder having a piston and fluid ports at its opposite ends, a directional valve for selecting the direction of piston actuation, and a metering control valve coupled between the directional valve and the cylinder. The control valve includes a cylinder section having a control piston therein and a valve body connected to the cylinder section and having a valve spool-receiving cavity therein. The valve body has first and second fluid ports therein communicating with the cavity, one of the valve body ports being coupled to one of the power cylinder ports and the other being coupled to the directional valve. A valve spool is disposed in the valve body cavity operatively connected to the control piston and movable therewith, the spool having a passage therein.