Abstract: A slide valve comprises a valve body having valve ports and a slide mounted within and slidable relative to the valve body for controlling the opening, interconnection and closing of the valve ports. The slide carries a valve block forming a sealing member which is floatingly located in a recess in the slide and which includes one or more galleries to provide interconnection between two or more of the ports in one or more defined positions of the slide. The sealing member also has at least one sealing surface for sealing off one or more of the ports in one or more defined posiitons of the slide. The sealing member is urged into its sealing position solely by means of fluid pressure applied through at least one of the ports.

Abstract: A fluid motor operated by a gas or liquid and having two relatively rotatable parts comprises a plurality of pistons which cooperate with a cam member to produce the rotational output from the motor. The cam member has at least three similar lobes and forms one of the parts and the other part includes at least four cylinders each containing a piston. Each piston/cylinder combination also acts as a slide valve so as to control both the supply of fluid to one of the other pistons and the exhausting of fluid from another of the other pistons.