| 摘要 |
PROBLEM TO BE SOLVED: To maintain a clean state inside an exhaust hose by driving a pumping motor in the opposite direction to that of pumping after the pumping motor is turned to take out water from a bucket and returning the water which is left over in the exhaust hose to the bucket. SOLUTION: When a lever switch 5 is turned on, a microprocessor 100 outputs a normal rotary drive signal where a normal direction drive unit 300 turns a pump motor 500 in the normal direction and takes out water from a bucket by way of an exhaust hose. When the lever switch 5 is turned off, the microprocessor 100 stops the operation of the pump motor 500 and ends the taking out of water. After a specified time has elapsed since then, the microprocessor 100 outputs a reverse rotary drive signal while a reverse direction drive unit 400 turns the pump motor 500 in the opposite direction, thereby returning water remaining in the exhaust hose to the bucket. This construction makes it possible to maintain a clean state in the exhaust hoe and remove a foreign matter deposited on a filter. |
