| 摘要 |
<p>The combination of a valve (13) comprising a closure member (11) operated by a moving spindle (12), the spindle being adjustable so that by selective positioning of the closure member the desired valve throughput can be achieved, and a drive member (1) operating over a suitable stroke to modify the adjustment of the spindle. The member is connected to the spindle by a first (2) and a second (6) lever able to operate in such a way as to convert a given stroke of the drive member into a functional displacement of the spindle. The first lever (2) has one end (at 3) rotatably coupled to the drive member (1). A pivot pin (4) is mounted near its other end and rotatably coupled, at point E by a coupling means, to the second lever (6). The second lever (6) has one end connected to the spindle (12). The coupling means comprises slide means to modify the real position of point E. The valve closure member (11) is a rotary member and the spindle (12) is mounted rotatably in the valve. One end of the second lever (6) is attached to the spindle (12) in order to rotate with it. The coupling means imparts an angular displacement to the second lever (6) in such a way that the spindle (12) and the closure member (11) are in turn angularly adjustable by the second lever so as to allow the desired throughput to be selected while the stroke of the drive member (1) remains unchanged. <IMAGE></p> |
