Patent ID: 7762094
Filing Date: 2010-07-27
Classification: F25B,Y02B

Abstract:
1. A valve control system for controlling a variable opening valve maintainable in a plurality of opening degrees between a fully open position and a fully closed position, said system comprising: a sensor which detects a control amount; a control unit which calculates a variation between the control amount and an aimed value for the control amount based on an output of said sensor, calculates an operation amount for actuating said valve as a control object based on the calculated variation, corrects the calculated operation amount to a predetermined value equal to or smaller than a predetermined limit value in a case where the operation amount exceeds the limit value, and outputs the calculated operation amount or the corrected operation amount; and an actuator operably communicated with said valve to control the opening degree of said valve in accordance with the operation amount output from said control unit; wherein said actuator comprises a pulse motor; and said control unit calculates a number of pulses as pulse signals to be supplied to said pulse motor based on the variation, and limits the number of pulses to be supplied to a predetermined value equal to or smaller than a maximum number of pulses that can be responded to by said pulse motor in one period, in a case where the number of pulses to be supplied is larger than the maximum number of pulses.