| 摘要 |
PURPOSE:To lengthen the life of a valve by inclining the wall surface of a gas passageway of a valve seat to the moving direction of a valve plate, and rotating the valve plate by flowing of gap passing through the gas passageway to uniformalize abrasion of the valve plate extending over the whole surface thereof. CONSTITUTION:A gas passageway 1 of a valve seat 2 has wall surfaces 1A, 1B inclined to the moving direction A of a valve plate 2. In this arrangement, gas obliquely flows into the valve plate 5, so that the valve plate 2 receives turning torque to be rotated a little. As gas flows intermittently, the valve plate is rotated little by every time gas flows so as to change a contact place of a valve spring 6 with the valve plate 5. Accordingly, abrasion is caused extending over the whole surface thereof to lengthen the life of the valve plate. |
