| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an analog control circuit for driving a fan, easy in troubleshooting and maintenance, and efficiently cooling the liquid with a simple constitution by continuously rotating the fan by using an inexpensive analog circuit. <P>SOLUTION: This analog control circuit for driving the fan comprises a DC power source, a temperature sensor detecting a temperature of a liquid to be cooled by the fan, and outputting a temperature signal in proportion to the temperature, a temperature determining circuit receiving the temperature signal and outputting a first command current corresponding to the temperature, a differential amplification circuit for amplifying the first command current and outputting the same as a second command current, a drive circuit receiving the second command current and the DC current and outputting the drive command current to an electromagnetic proportional valve, and the electromagnetic proportional valve receiving the drive command current and controlling a rotating speed of the fan. <P>COPYRIGHT: (C)2004,JPO |
