Patent ID: 6286412
Filing Date: 2001-09-11
Classification: E02F,F15B

Abstract:
A control system for an electrohydraulic valve used to control the operation of a work element through the use of operator input control mechanisms generating operator input signals upon the application thereof, the valve being connected to the work element via a hydraulic circuit which includes an actuator coupled to the work element for controlling the operation thereof, the control system comprising:a flow sensor positioned in communication with the valve and adapted to determine an actual valve output flow rate of a hydraulic fluid flowing therethrough, the flow sensor outputting a signal indicative of the actual valve output flow rate;a pressure sensor positioned in communication with the actuator and adapted to sense a load pressure being applied to the actuator, the pressure sensor outputting a signal indicative of the load pressure;desired valve output flow rate determinator in communication with the pressure sensor and the operator input control mechanisms for receiving the load pressure signal and the operator input signal and determining a desired valve output flow rate for the valve based thereon, the determinator outputting a signal indicative of the desired valve output flow rate;a comparator in communication with the flow sensor and the desired valve output flow rate determinator and adapted to receive signals therefrom, said comparator being operable to compare the actual valve output flow rate with the desired valve output flow rate and produce a comparator output signal representing a difference therebetween; anda controller in communication with the comparator and the valve and adapted to receive the comparator output signal and modify an input flow rate signal to the valve based upon the comparator output signal such that the desired valve output flow rate from the valve is achieved.