| 摘要 |
PURPOSE:To protect an engine from seizure without fail by a method wherein the abnormal operation of the engine is detected on the base of at least one of parameters such as the quantity of a lubricating oil, the supply pressure of the lubricating oil, the temperature of the engine and the engine r.p.m. and the supply of fuel to the engine is stopped. CONSTITUTION:An oil quantity abnormality detecting circuit 17 which is connected in series with a chattering removing circuit 18 and a NOT circuit 19 is connected to a float type oil level sensor 9 provided in the oil sump 8 of an engine. Further, an oil pressure abnormality detecting circuit 21 and an overheating detecting circuit 23 each having the same series circuit structure as the circuit 17 are connected to an oil pressure switch 11 provided in a pressure oil passage 10 and a thermo-switch 12 provided in a water jacket, respectively. In addition, an abnormal rotation detecting circuit 26 adopted to detect the abnormal rotation of the engine through high and low speed comparison circuits 30 and 29 after the output of an engine r.p.m. sensor 14 is rectified by a rectifier 27 and then passed through a F/V converter 28, is provided. Thus, when an output is generated from any one of the above-mentioned circuits 17, 21, 23 and 26, a contact 53 of a relay 52 is opened and an electromagnetic valve 5 in a fuel gas supply passage is closed. |
