Abstract: A new control system is provided for a reciprocating fluid stroke motor of the type which is pressured at its rod end, reciprocation being achieved by intermittent exposure of its full blind-end face to the pressure fluid to overcome the pressure applied to its smaller rod-end face. The control means includes a valve for a passage through the piston, with adjustably-positioned trip-stops for shifting the valve between open and closed positions. The valve is biased to snap fully open when the piston movement toward its opening-stop opens it slightly and remain open until striking the closing-stop. Monostable or bistable trip-switch types of biasing means may be used, and unless one holding the valve closed with no fluid pressure is chosen, resumption of pressure supply after discontinuance will cause an initial retraction of the piston to its starting position, allowing time for the controlled apparatus to attain acceptable speed.

Abstract: The valve of this invention connects a source of water sequentially to separate outlet connections. A piston is moved by the water pressure through a forward stroke which determines the duration of the existing connection. The duration is adjustable by a throttle (one corresponding to each connection) which regulates the speed at which fluid is discharged by the piston. At the end of the timing stroke the piston indexes itself to a new position, moving likewise two selector valve discs, one to make a new outlet connection for the water supply and one to select the corresponding throttle for timing. Also a cycle control valve opens at the end of the timing stroke to let a return spring move the piston through a return stroke.