| 摘要 |
PURPOSE:To reduce oscillation and noise of an engine at its idle operation, by slidably protruding a piston to an intake pipe, responsively moving the piston in accordance with a flow of intake air and throttling an intake passage. CONSTITUTION:A piston 2 is slidably protruded to an intake pipe 1, and a throttling part 16 is provided between a Venturi 15 of intake pipe internal wall and the point end of the piston. At idle time, though pressure P2 becomes large negative pressure, negative pressure P1 is not increased. Large negative pressure is introduced from a through hole 17 to a negative pressure chamber 12 in a negative pressure type actuator 9, and a diaphragm 10 and the piston 2 are moved rightward. In this way, intake air is throttled, and oscillation and noise of an engine can be reduced. |
