Patent ID: 6390379
Filing Date: 2002-05-21
Classification: F24F,H05K,Y02B,Y10S

Abstract:
A method for controlling a revolving speed of a heat-dissipating fan, said fan being mounted to an electronic apparatus and revolving for dissipating heat generated during the operation of said electronic apparatus, said method comprising steps of:predetermining a target temperature and a tolerance value; performing a temperature-measuring step of measuring a current temperature of said electronic apparatus in operation; performing a temperature-comparing step of comparing said current temperature with said target temperature; performing a selective signal-output step of outputting a triggering signal to change the revolution of said fan when a difference between said current temperature and said target temperature is greater than said tolerance value; and respectively determining an actuating value of an electric power supplied to said fan to actuate the revolution of said fan and a suspending value of said electric power to stop the revolution of said fan, comprising steps of: providing an electric power for said fan in a motionless state; intermittently stepping up said electric power to revolve said fan, and detecting a revolving speed of said fan at each power-change step; determining a first threshold value of said electric power making said revolving speed of said fan exceed a first given value as said actuating value; intermittently stepping down said electric power provided for said fan in a motional state, and detecting a revolving speed of said fan at each power-change step; and determining a second threshold value of said electric power making said revolving speed of said fan lower than a second given value as said suspending value.