| 摘要 |
PURPOSE:To widen the controllable range by providing possibility of changing over a neg. pressure chamber of an exhaust gas by-pass valve, which is to retain a gas modifier installed in the exhaust passage of a modified gas engine at a certain specified temp., from the neg. pressure source to the atmospheric side and vice versa. CONSTITUTION:An exhaust by-pass valve 6 is installed at a gas modifier casing 2, and when this valve 6 is opened the modifier 1 is protected from the hot exhaust gas. Neg. pressure chamber 9 of a neg. pressure actuator 8 is put in communication with the valve chest 24 of a three-way solenoid valve 22 through a piping 23. A port 25 of this three-way valve 22, which is opened when current is supplied is put in communication with a constant neg. pressure chamber 17 through a piping 26 equipped with a surge tank 27, and a port 28 which is closed when current is supplied is released to the atmospheric side. According to this arrangement neg. pressure is consumed only when the exhaust by-pass valve is half opened while no neg. pressure is consumed when the valve is fully closed, so that the controllable range of the exhaust by-pass valve is greatly widened. |
