To prevent a motor from being burnt due to jaming of soil by providing a motor device for driving a pump motor in a water washing mode of storing the on-state of an operation switch of the motor and operating for a fixed time from that point to be stopped, and in a remaining water discharge mode of repeatedly operating several times shorter than the water washing mode.
In a microcomputer of a control circuit, when an operation switch 17 is turned on, a water washing mode is read, a pump motor 9 is driven during the time t1, and then it transits to a remaining water discharge mode. In the remaining water discharge mode, the pump motor 9 is driven during the time t2 in the lapse of 2 seconds after the water washing mode, and further driven during the time t2 in the lapse of t3 after that. Repetition of this discharge mode is arbitrarily set according to the use environment. Thus, soil can be completely discharged to the outside of a ship regardless of the immature of operation, so that burning of the pump motor can be prevented, and as remaining water in a toilet stool is not produced, even if the ship rolls, water is kept from being spilt in the toilet room.
NINOMIYA TAKAYUKI
ISHIZAKI KAZUHISA
HITACHI CAR ENG CO LTD