| 摘要 |
PROBLEM TO BE SOLVED: To reduce friction between a rotational shaft and a bearing to ensure a large opening angle of a valve member, by lowering energization force of an energization member energizing the valve member in a closing direction.SOLUTION: A valve member 38 of a valve structure 32 is rotatably supported to an outer cylinder 34 by a rotational shaft 40. The rotational shaft 40 is fixed to the valve member 38 inside the tangent line of the outer periphery of the valve member 38 and at a position of avoiding a center point. A return spring 52 is a tension spring, which makes tension force generating rotation force of the valve member 38 in a closing direction always act on a link arm 54.SELECTED DRAWING: Figure 1 |
