Vorgesteuertes Fluidumventil

摘要

A gas purge valve comprising a housing (2) provided with an inlet (22) for connecting to a liquid system to be purged. A flexible diaphragm (14) formed with an aperture (16) of restricted dimension is maintained in the housing dividing it into first (18) and second (20) chambers, the first chamber communicating with the inlet. A pilot valve (30) controlled first outlet (26) is formed in the second chamber and a second outlet (42) is formed in the first chamber. There is also provided a diaphragm seating (46) formed in the first chamber, being engageable by said diaphragm so as to seal said second outlet; the arrangement being such that the pilot valve is displaceable between a first position in which gas is discharged from the second chamber so as to vent the second chamber and a second position in response to liquid presence, so as to seal the first outlet. The diaphragm is displaceable in response to differential pressure created by the venting into unsealing the second outlet for full venting of the first chamber. <IMAGE>