| 摘要 |
<p>A valve (400) comprising a tapered wedge gate closure member (424) which is actuated by a stem (422) that is operatively connected with the valve operator at the upper end, the lower end of the stem connected to a toothed pinion (432) engaging an arcuate toothed rack (430) on the gate (424), or to a toothed pinion (532) engaging a linearly straight toothed rack (530) on the gate (524), thereby reciprocating the gate (424) across the fluid flow path (412-414) in a direction transverse to the stem axis, and the stem (422) is operatively connected with the valve operator by means of a stem moving means that causes selective axial and rotary movement of the stem (422).</p> |
