| 摘要 |
<p>The valve uses a rotatable conical cock (3) to control a flow of gas through a casing (1) permitting a gradual progression from closure to maximum discharge. The cock blocks a radial feed (4) at closure, moves initially into a 'pilot light' position with a calibrated orifice (7) connecting the feed to an axial passage (5), and then rotates through a significant angle to reach the point of maximum discharge. During the latter cock movement a specially shaped notch (8) connects the feed to the passage gradually increasing the through flow. The notch has a wedge shape and connects the passage to the conical surface, having a conical face (20) together with a plane face (21) normal to the axis of rotation. The conical notch face intersects that of the cock to form an elliptical lip, the plane face being offset from the feed.</p> |
