| 摘要 |
PROBLEM TO BE SOLVED: To provide a swing valve type valve device suppressing a pressure loss and flow rate sensitivity in a low opening.SOLUTION: A projection 31 is provided on a back surface of a valve body 23, and a tapered passage α is formed between the projection 31 and a second exhaust scroll 22. When the valve body 23 is opened, exhaust gas passing through a part between the valve body 23 and a seat surface 22a changes a direction to a down stream side by the projection 31, and smoothly flows in a downstream direction, thereby suppressing peeling on the back surface of the valve body 23. Therefore, a pressure loss can be greatly reduced, and turbine efficiency can be improved. At least in a low opening, the projection 31 is inserted in the inside of the second exhaust scroll 22, so that an increase of a passage area to opening change can be suppressed. Therefore, flow rate sensitivity in the low opening can be suppressed, and the accuracy of flow rate control of the exhaust gas can be improved.SELECTED DRAWING: Figure 3 |
