| 摘要 |
<p>The valve controller uses compressed air with feedback and a converter station to supply a signal for a servo motor. The position of the servo motor is indicated by a spring between the measuring device and the motor. The regulator cancels out the effects of friction and changing forces on the valve stem. The spring is of the helical type (41), with one end rotated by a lever operated by the servo motor. The other end of the spring is connected to the measuring device. The pressure is measured by a diaphragm (33, 34) whose neutral position is in line with the axis of the adjustment shaft (42).</p> |
