| 摘要 |
<p>PURPOSE:To reduce the production of white smoke without increasing back pressure by providing a bypass pipeline equipped with a filter so as to bypass a muffler in the exhaust pipe of an engine, so that the outlet of the bypass pipeline can be opened by a valve body as the exhaust pressure decreases. CONSTITUTION:When the exhaust gas pressure at the downstream side of a muffler 13 decreases at the time of low-temperature starting of an engine, at the time of idling, or at the time of light load operation or the like, the force to turn a valve body 17 in the closing direction via a flap 19 is weakened. Therefore, the valve body 17 is turned by gravity via a hinge pin 18 in the clockwise direction, so that the outlet of a bypass pipeline 14 bypassing the muffler 13 part of an exhaust pipe 12 is opened, and at the same time the exhaust pipe 12 is closed. As a result, the exhaust gas containing white smoke flows in the bypass pipeline 14 in which a filter 15 is provided, thereby hydrocarbon and its oxide which produce white smoke are caught by the filter 15. Thus, the white smoke to be discharged from the exhaust pipe 12 can be reduced.</p> |
