Control valve with mechanical feedback and method for controlling fluid flow

摘要

A control valve (14) and a method of controlling fluid flow include an input device (20) which provides an input for moving a primary valve member (100) an amount which is a function of the input, thereby opening flow pathways through the valve (14). The control valve (14) is connected to a mechanical feedback mechanism which moves a feedback valve member (106) an amount which is a function of the movement of a device to which the fluid flow is directed, such as a hydraulic actuator (12). Movement of the actuator (12) to a desired position causes the second valve member (106) to be moved to such a position that, in combination with the first valve member (100), the flow pathways through the valve (14) are closed. The actuator (12) is thereby moved to and maintained at the desired position without the need for the electronics feedback sensor used in prior art systems to sense actuator position.