| 摘要 |
<p>PURPOSE:To reduce the energy loss of a turbine used for a supercharger, by constituting the turbine scroll by a main exhaust passage and an auxiliary exhaust passage which are both shaped in a spiral form and disposed in side-by-side relationship with each other, and providing a gate valve on the upstream side of the portion where a groove for communicating the auxiliary exhaust passage with the main exhaust passage is formed. CONSTITUTION:A turbine scroll 13 is separated by a partition wall 5B and includes a main exhaust passage 13A and an auxiliary exhaust passage 14B which are both shaped in a spiral form. These two exhaust passages 13A, 13B are communicated with each other via a connecting portion 15, the width B of which is made constant over the entire length thereof. The connecting portion 15 is formed to cover the region from the position near the tongue 16 where the scroll is started to the position near the throat portion 17. Further, a swing valve type gate valve 21 having an aerofoil profile conforming to the configuration of the inner wall surface of the scroll 13 is disposed such that the top 21A of the valve 21 comes to the position near the tongue 16 in the auxiliary passage 13B and the entire body of the valve 21 extends along the wall surface on the upstream side of the tongue 16 when the valve 21 is opened.</p> |
