Abstract: The invention relates to an electrohydraulic control assembly of the type having a slide valve unit for controlling the operating direction of a hydraulic servomotor. The assembly includes a bridge circuit between the pressure source and the drain tank which has a pressure operated valve in each of its four branches. Diagonally opposite bridge terminals between the supply and exhaust branches of the bridge circuit are connected operating chambers on opposite sides of the slide valve unit. The bridge circuit valves are operated by solenoid valves to achieve selective directional operation of the slide valve unit.

Abstract: The invention relates to a hydraulic regulator of a type which may be operated by electromagnetic switching valves. The assembly includes a piston and cylinder arrangement with position setting chambers at opposite ends thereof of larger diameter than the servo piston. Movable abutment elements in the chambers of larger diameter than the servo piston are biased by centering springs. There are parallel circuit branches in which the end chambers are disposed and switching valves are in these branches. The actuating of one of the valves to block its branch lower the pressure in the end chamber in that branch causing the piston to move towards the blocked branch so as to move away from the biasing force of the opposite spring biased element and engage the biasing force of the adjacent spring biased element. When the other switching valve is actuated to block its branch to stop the piston in a desired position, the fluid pressure in the end chambers is equal.

Abstract: The invention relates to a hydraulic regulator of a type which may be operated by electromagnetic switching valves. The assembly includes a piston and cylinder arrangement with position setting chambers at opposite ends thereof of larger diameter than the servo piston. Movable abutment elements in the chambers of larger diameter than the servo piston are biased by centering springs. There are parallel circuit branches in which the end chambers are disposed and switching valves are in these branches. The actuating of one of the valves to block its branch raises the pressure in the end chamber in that branch causing the piston to move in the other direction so as to move away from the biasing force of one spring biased element and engage the biasing force of the other spring biased element. When the other switching valve is actuated to block its branch to stop the piston in a desired position, the fluid pressure in the end chambers is equal.