| 摘要 |
PURPOSE: To reduce a motor output and to lower a noise level by setting a second pressure switch which is worked by a pressure level in an exit path exceeding a predetermined level to work a control circuit. CONSTITUTION: A control circuit 20 which is connected to a motor 15 is worked to reduce a motor output till a predetermined level. A first pressure switch 21 to which the control circuit 20 is connected is worked by pressure in a filter chamber 12, and works the control circuit 20, when this pressure decreases below the predetermined pressure level. Therefore, negative pressure to attract a nozzle on a face to be cleaned is prevented from excessive increasing. A second pressure switch 22 which is connected to the control circuit 20 in parallel with the first pressure switch 21 works the control circuit 20, when a pressure level in a exit path 17 between a suction fan 14 and an exit 16 exceeds the predetermined level. Hence, a flow of air flowing through this suction type cleaner and, therefore, a noise level are reduced corresponding to decreasing of suction resistance such in the case of releasing the nozzle from the face to be cleaned.
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