| 摘要 |
<p>A pilot diaphragm valve (10) for a pulsator in a milking plant comprising a piston diaphragm valve (11), wherein the position of a piston (12) is determined by the pressure on a diaphragm (14) and wherein a diaphragm chamber (22a) on one side of the diaphragm communicates with the pilot valve (13). A toggle arm (26) is arranged in a wall of the pilot valve chamber, and one end of said toggle arm forms a movable valve member (26a) adapted to alternately open and close a vacuum inlet and an air inlet (42, 46). The other end (26b) of the toggle arm protrudes out of the valve chamber (25) and engages a displaceable slider (28) comprising a plurality of permanent magnets (31) mounted in such a manner that two magnetic poles of the same type face each other and may slide into a coil (32) adapted to be connected to an electronic circuit being able to supply the coil with current pulses, the direction of which may alternate at the desired frequency for changing the pressure on the teat cup of the milking machine between vacuum and atmospheric pressure. As a result, a current controlled valve having very small electric power consumption is obtained.</p> |
