| 摘要 |
In an EGR valve, a valve element is moved with respect to a valve seat to adjust a passage section width of a measuring section, thereby regulating an EGR gas flow rate in a passage. The valve seat includes a valve hole, a first end face facing to a downstream side of the passage and a second end face facing to an upstream side of the passage. The inner circumferential surface of the valve hole has a concave curved shape with an inner diameter gradually increasing toward the second end face. The valve element is placed inside the valve hole to be movable in between a fully closed position and a fully open position. While the valve element is placed in the fully open position, passage section widths of parts of the measuring section in an EGR gas flow direction are approximate to each other. |
