| 摘要 |
The fuel/air ratio of a mixture of air and a fuel containing petrol and a substantial portion of partially oxygenated hydrocarbons, for example ethanol or methanol, is maintained at or close to stoichiometric by a closed loop control. The control includes an oxygen sensor 14 in the exhaust from the combustion chamber 10 which provides a state signal E1 indicating whether burning is below or above stoichiometric. The state signal is processed by an air-to-fuel ratio control circuit 22 to provide a control signal E2 that biases an air-to-fuel ratio control mechanism 20 in a direction that maintains the air-to-fuel ratio within a very narrow band around stoichiometric. A three-way catalyst is employed to minimize the pollution output from this internal combustion system and because of the closed loop control, the catalyst's effectiveness is optimized. <IMAGE> |
