Patent ID: 9689507
Date: 2017-06-27
CPC Classifications: F16K

Claim:
1. A vacuum valve including a valve opening and a valve plate that opens and closes the valve opening, wherein a part of an edge of the valve opening is a wedge edge portion having a wedge shape projected outward, and the wedge edge portion is provided in a region where the valve plate starts to open the valve opening when the valve plate is moved to open the valve opening, and further wherein a vertex of a wedge of the wedge edge portion is located at a position where an edge of the valve plate first comes into contact with the edge of the valve opening, the wedge edge portion includes a first straight line segment extending from the vertex, a second straight line segment extending from the vertex, a first circular arc extending from the first straight line segment, and a second circular arc extending from the second straight line segment, and the edge of the valve opening further includes an arc of a circle connecting the first circular arc and the second circular arc.