| 摘要 |
PURPOSE: To automatically adjust the number of revolution of a motor for rotary brush drive to reduce damage on a carpet, by connecting a rectifying diode to the motor for rotary brush drive with a rectifying diode to make half-wave rectification of an AC power source in series and an electromagnetic relay to close on receiving a dust detecting signal from a dust detecting part with the rectifying diode in parallel. CONSTITUTION: When dust is detected at a dust detecting device 15 by connecting a power source 12 to rotate an air blowing motor 11, a dust detecting signal is transmitted from a dust discriminating circuit 16 to a phase control circuit 14 and a continuity angle of a directional thyristor 13 is displaced to increase the number of revolution of the air blowing motor 11 is increased for a prescribed time. When a switch is closed, a rotary brush drive motor 17 is driven, and when no dust is detected by the dust detecting device 15, half-wave rectifying of the AC power source is carried out by a rectifying diode 19 to reduce the number of revolution of the rotary brush drive motor 17 to a half. When dust is detected by the dust detecting device 15, the contact point of an electromagnetic relay 20 is closed to supply all wave of AC to the rotary brush drive motor 17 to make high speed operation for a prescribed time, and then the motor returns to the original condition and the rotary brush makes seeping out dust in a carpet. |
