OIL COOLER CONTROL METHOD AND OIL COOLER CONTROL UNIT

摘要

PROBLEM TO BE SOLVED: To provide an oil cooler control unit capable of preventing the oil leakage by the thermal distortion of the oil cooler corresponding to the change of the ambient temperature. SOLUTION: The oil cooler control unit controls the revolving speed of a variable speed fan 19 that supplies the cold wind to the oil cooler 16 to cool the working oil in an oil pressure circuit 14. A target temperature setting means 31 sets up a variable temperature obtained by adding the prescribed temperature to the ambient temperature as the target temperature of the working oil control when the ambient temperature detected by the ambient temperature sensor 28 is in the prescribed low temperature range. The target temperature setting means 31 sets up the prescribed highest control temperature of the working oil in the low temperature range as the target working oil control temperature when the ambient temperature exceeds the prescribed low temperature range. The fan revolving speed control means 32 controls the revolving speed of the variable speed fan 19 so that it makes the working oil detection temperature detected by the working oil temperature sensor 29 correspond to the aimed working oil temperature detected by the aimed temperature setting means 31. COPYRIGHT: (C)2004,JPO&NCIPI