| 摘要 |
PROBLEM TO BE SOLVED: To provide a drainage device that can be manually operated even if trouble occurs to detection means.SOLUTION: If an error in detection of an angular position of a crank 34 by an upper sensor 61 occurs after control over rotational driving of a motor starts, the motor is stopped after a time which is a predetermined multiple of a time of one rotation passes after the crank 34 starts rotating. The motor is thus stopped after the time which is the predetermined multiple passes, so that the crank 34 can be put back to the position where the crank 34 starts rotating, i.e. an initial position. |
