Abstract: A fluid working machine comprising a controller and a working chamber, an electronically controllable low pressure valve associated therewith and a fast high pressure valve associated therewith, characterized in that the working chamber has associated therewith a slow high pressure valve for controlling the connection of the working chamber to a secondary high pressure manifold. A fluid working machine according to the invention may be operated to rotate its shaft to a certain position, for example to allow easy maintenance of a wind turbine generator.

Abstract: In an engine having at least one cylinder with a reciprocating piston and a connecting rod for driving rotation of a crank disk and a crankshaft, a cam sleeve is moved along the crankshaft in response to a change in engine speed. The cam sleeve is coupled to a cam ring that moves with the cam sleeve and in a spiraling motion about the longitudinal axis of the crankshaft. A follower engages an outer face of the cam ring and is movable against a pushrod that opens an injector valve. The follower is structured and disposed to move in response to contact with a lobe on the outer face of the cam ring to urge the pushrod against the injector valve. The pushrod passes through a throttle control ring that rotates in an arc. Rotation of the throttle ring, with the use of a control lever, shifts the position of the pushrod on the follower relative to a fulcrum of the follower to control the distance the pushrod is driven by the follower and, thus, the amount the injector valve is opened.