| 摘要 |
PURPOSE:To plan to clean the exhaust gas and improve the capacity of operation by a method wherein an exhaust gas recirculation control valve is controlled by a most suitable EGR rate commanding signal generating device generating the signal in accordance with a detected temperature and the revolving number of the engine detected by an exhaust gas temperature senser and a revolving number senser. CONSTITUTION:A central processor unit (CPU)41 discriminates the difference between an acceleration detected by an acceleration senser 47 and the predetermined value thereof when a water temperature detected by a cooling water temperature senser 46 is higher than the predetermined value thereof. If the acceleration is smaller, the CPU41 reads out a memorized value in accordance with the combination of an exhaust gas temperature and a revolving number detected by an exhaust gas temperaure senser 44 and an engine revolution number senser 45 from a memorizer 42 and outputs a signal in accordance therewith to a pulse signal generating circuit 43. The circuit 43 outputs a pulse signal having a duty ratio in accordance with the signal to a vacuum control valve 26 and the valve 26 connects repeatedly a port C to the ports A, B with a constant time ratio in accordance with this ratio, thereby generating a vacuum in the port C. This vacuum controls a diaphragm 19 and the valve port 16 of the exhaust gas recirculation control valve 13. |
