| 摘要 |
PURPOSE:To announce a warning of the abnormal operation of an exhaust gas reflux device and stop its operation so as to protect an internal combustion engine by detecting the normal and abnormal condition of said device using a detector. CONSTITUTION:An intake and exhaust manifolds 2, 8 of an internal combustion engine are communicated with each other by means of an exhaust gas recirculation passage 16 having an exhaust gas return valve 17 which is actuated by an electromagnetic valve 19 regulating the negative pressure of a negative pressure passage 18. Signals from lead switch 7 detecting the acting of a pulse motor 5, a sensor of O2 in the exhaust gas system, an atmospheric pressure sensor 10, and a negative pressure sensor 15 are input to an electronic control circuit 6, while a control valve 4 of a carburettor and the valve 19 are feed-back-controlled. The control circuit 6 judges it abnormal when the difference between output and input levels exceeds a predetermined value and makes the valve 19 to close the valve 17. |
