Patent ID: 6571190
Filing Date: 2003-05-27
Classification: G01L

Abstract:
A computer calibration method for calibrating a plurality of auxiliary hydraulic proportional control valves in a bi-directional flow control circuit in a work vehicle, wherein the inlet of each of the plurality of valves is provided with pressurized hydraulic fluid from a common source and wherein the outlet of each of the plurality of valves is fluidly coupled to a common load sensing circuit and is also configured to be fluidly coupled to an implement, and further wherein the load sensing circuit is fluidly coupled to the common source to control the specific hydraulic fluid output of the common source, and further wherein all of the plurality of valves are driven by an electronic controller that is configured to generate an electrical signal proportional to a desired degree of opening of each of the plurality of valves, the computer method comprising the steps of:(a) selecting a first valve of the plurality of valves; (b) applying a signal to the first valve equivalent to a first degree of desired valve opening; (c) measuring a first pressure in the load control circuit; (d) comparing the first pressure with a predetermined pressure to identify a change in pressure indicative of the first valve opening; (e) incrementing the signal to a second desired degree of valve opening greater than the first degree of valve opening if the step of comparing does not indicate that the first valve has opened; (f) repeating steps (b)-(e) until the first valve opens; (g) saving a value indicative of the signal.