Patent ID: 6364281
Filing Date: 2002-04-02
Classification: F16K

Abstract:
A method of actuating a solenoid operated valve for providing fluid flow proportional to electrical energization with minimal hysteresis comprising:(a) energizing the solenoid for increasing flow initially by a fractional amount of current in excess of the current required for the desired increased flow for a predetermined relatively short interval (overstep) and thereafter energizing the solenoid at the current required for the desired increased flow; and, (b) energizing the solenoid for decreasing flow initially by a certain amount of current less than the current required for the desired decreased flow for a predetermined relatively short interval (understep) and thereafter energizing the solenoid at the current required for the desired decreased flow whereby said overstep and understep minimize the hysteresis between energizing the coil for increasing and decreasing flow.