| 摘要 |
<p>A variable orifice dual gate valve (10) having two opposed slidable valve gates (14, 15) in overlapping sliding contact relationship. Inner orifice edges (16, 17) of these plates coact to form a variable size orifice in the valve body (11) upon simultaneously sliding of the valve gates (14, 15) in opposite directions through manipulation of a gear and screw drive mechanism (20). The gear and screw drive mechanism (20) includes a handle drive shaft (23) connected at an exposed end to a valve handle (22) and a drive gear (25) is secured to the other end of the handle drive shaft (23) for axial rotation. This drive gear (25) is meshed in driving engagement with two driven gears (26, 27) that in turn are respectively secured to drive right hand lead screw and left hand lead screw shafts (28, 29).</p> |
