| 摘要 |
PURPOSE:To surely prevent variation in operational response by providing a means, which can detect a no-load condition and a warm-up state of an engine, and by making the EGR control start under a no-load condition after the engine warming-up is completed. CONSTITUTION:When an engine 1 is started, a control device 9 checks whether the water temperature is lower than the set value, or whether the engine 1 is in a warming-up state, or not based on a detection signal from a water temperature sensor 14. When it is found out that the temperature is higher than the set value and the engine warming-up in completed, the condition for starting EGR is set. When the output from a throttle valve switch 11, which detects that a throttle valve 4 is entirely closed, indicates that the engine is under a no load condition, or that the condition for starting EGR is satisfied, the command ''Start EGR.'' is issued. With this contrivance, a negative pressure control electromagnetic valve 8 can be controlled so that regulated negative pressure is introduced into a negative pressure chamber of an exhaust reflux valve 6 in order to open the valve 6 as required, thereby making EGR start. |
