| 摘要 |
PURPOSE:To prevent overspeed operation of an engine, by feeding fuel superfluously and thereby causing incomplete combustion of fuel by reducing the opening area at the inlet of a venturi by bringing a plate member having a small opening into abutment with the inlet of the venturi when the amount of intake air supplied to the engine is increased. CONSTITUTION:At the time of ordinary operatin of an engine, a plate member 7 is forced onto an inlet stopper 10 by the force of a spring 9 irrespective of the quantity of intake air, so that a proper amount of intake air is supplied to the engine through a main air port 11 formed in the plate member 7 and a proper number of auxiliary air ports 12 formed around the main air port 11. On the other hand, when a throttle valve 3 is fully opened under the state that the engine is operated with low or no load, the flow rate of intake air is increased rapidly, so that the plate member 7 is moved in the direction of air flow against the force of the spring 9 until it comes into abutment with the upstream end face 8 of a venturi 2. Resultantly, intake air is passed to the vanturi 2 only through the main air port 11, so that the negative pressure developed at the venturi 2 is increased drastically and a large amount of fuel is supplied from a main nozzle 5. Therefore, the engine causes incomplete combustion and the engine out put is lowered. |
