| 摘要 |
PROBLEM TO BE SOLVED: To almost fixedly hold a changing width of a pressure of gas in a gas-sealed chamber, even when the changing width is increased in the pressure of gas in a pressure supply source connected to the gas-sealed chamber. SOLUTION: A pressure supply pipe 90 connects a gas-sealed chamber 84 to an intake manifold of an engine. When a solenoid opening/closing valve 92 arranged in a pressure opening pipe 94 is opened when the engine is operated, a pressure in the gas-sealed chamber 84 is changed to follow a change of gas pressure in the intake manifold. A pressure regulating valve 96 is opened when the pressure in the gas-sealed chamber 84 is lowered down to a lower limit value of preset operating pressure. In this way, the outside air is introduced through the pressure opening pipe 94 into the gas-sealed chamber 84, and a pressure drop therein is prevented. |
