| 摘要 |
<p>A dampener for a clapper valve wherein a rotor member having radially outwardly extending vanes which subdivide each of two fluid cavities defined in a housing into first and second fluid volumes is characterized by radially extending, first and second passages axially spaced within the rotor which respectively communicate each of the first volumes and the corresponding second volume. The increase in pressure within either of the volumes generated by the motion of the vanes (which move with the clapper) is accommodated by the fluid in one passage venting to the other passage through an axially movable valve. The valve piston presents equal surface areas to each passage, to thereby fluid balance the damper in both the opening and closing directions of the clapper. A bypass channel is provided through which one of the fluid volumes in the first cavity with one of the volumes in the second cavity.</p> |
