| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vacuum cleaner which can protect a commutator motor inexpensively at a stage as early as possible when abnormal spark is generated. <P>SOLUTION: Variation width is detected every predetermined time of a current on an electric circuit connected with a commutator motor (S1-S3), and in order to detect the fact that abnormal spark is generating in the commutator motor out of a predetermined number of times of a preset current variation width thus detected, the commutator motor is stopped (S5) on condition that the number of times when a preset upper limit threshold is reached is a preset number of times of abnormality (Yes side at S4). <P>COPYRIGHT: (C)2009,JPO&INPIT |
