To provide a coolant apparatus capable of detecting an abnormal leakage of a coolant and clogging of a coolant passage.
A control device 14 controls the rotating speed of a motor 5 for driving a pump 4 to hold the pressure of the coolant to a prescribed pressure according to the coolant pressure detected by a pressure sensor 9. The control device 14 stores the rotating speed of the motor in the initial stage of operation of a coolant pumping apparatus, as the initial rotating speed. When the rotating speed of the motor is increased to the prescribed rotating speed or higher in relation to the initial rotating speed following the fall of volumetric efficiency due to the internal wear of the pump 4, the control device 14 detects the leakage of the coolant.
YAMAZAKI KEIJIRO
HORIUCHI HITOSHI
| JP2004036421A | 2004-02-05 | |||
| JPS6235915Y2 | 1987-09-11 |
Atsushi Maeda
Yukinori Nakakura