| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent fluctuating sound caused by the revolution number in operation of a compressor. <P>SOLUTION: The revolution number is calculated in the revolution number calculation means 109, the revolution number of the command revolution number is compared with the calculated revolution number of a DC motor 104, and the revolution number of the DC motor 104 is controlled to be the command revolution number by the revolution number control means 108. If a duty ratio output from the revolution number control means 108 is 100%, the revolution number lower than the command revolution number is selected from set revolution numbers stored in a set revolution number storage means 114, the selected revolution number is compared with the revolution number calculated in the revolution number calculation means 109, and the compressor is operated for a given length of time by using a timer 117 to control the revolution number to be the selected revolution number, so that the fluctuating sound of the compressor 115 is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
