| 摘要 |
PROBLEM TO BE SOLVED: To reduce burden applied on a battery and a power generator for charging it by carrying out current-carrying to an intake pre-heating device intermittently, when current-carrying is carried out to the intake pre-heating device after a diesel engine is started and after heating is carried out to pre-heat intake air supplied to a combustion chamber. SOLUTION: When a diesel engine is operated, current-carrying is carried out to the electric heater 9a of an intake pre-heating device 9 after the engine is started, and pre-heating is carried out. After the engine is started, current- carrying is carried out to the electric heater 9a, and after heating is carried out. At the time of after heat, an electromagnetic relay is turned on/off by a set duty ratio when it is detected by a temperature sensor 11 that the temperature of engine cooling water is a setting value or less, and current-carrying is carried out to the electric heater 9a intermittently. After current-carrying is started to the electric heater 9a, the electromagnetic relay 8 is held in an off condition when it is detected that the temperature of cooling water exceeds the setting value, and intermittent current-carrying is stopped to the electric heater 9a. |
