Patent US 4,072,087

A digital positioner for remote actuation of a control valve includes a double-acting actuating piston connected to the control valve and a plurality of fluid-responsive stop means disposed to either side of the actuating piston. A plurality of remotely controlled pilot valves are operatively connected to respectively control the actuating piston and selected ones of the stop means. The system is especially adapted for remotely controlling hydraulic systems having a control valve for modulated control of the system for different speeds of the system.