| 摘要 |
PURPOSE:To prevent from hysteresis phenomena while reducing the power of a motor fan in both areas of a large air volume and a small one by settling set values for switch level and for reset level as control values based on a detected value by the use of a pressure sensor, and by controlling the power of a motor fan according to these two set values. CONSTITUTION:A controller 11 of a vacuum cleaner 1 consists of an electric circuit or an electronic circuit containing central processing unit such as microcomputer, and controls a motor fan 2 corresponding to detected values by the use of a pressure sensor 12. The pressure sensor 12 is installed at a downstream part of a filter 4, or inside of a dust case 5 or an upper stream part of an inlet port 8 side. As the set value for reset level can be a specified reset value corresponded to the controlled state newly switched, resetting at the same operating point as that at the time of switching is possible so that hysteresis phenomena can be prevented. |
