| 摘要 |
PURPOSE:To provide sensible adjustments of weak gas pressures, by maintaining the line pressure by means of magnetic fluid sealing adapted to be momentarily broken if an over pressure arises in the line thereby to let off the over pressure. CONSTITUTION:The top portion 52 of a core member 5 is made in a truncated cone shape and opposing ring-shaped magnetic pole members 61, 62. A magnetic fluid 4 is enclosed in the portion for sealing the same around the circumference of the truncated cone 52, a permanent magnet 6, and the magnetic pole members 61, 62 which, together, form a magnetic flux passing portion. When a high pressure arises in the line, the magnetic fluid seal is broken to momentarily relieve the line from the pressure thereby to adjust it to a predetermined pressure. The gap for the magnetic fluid seal is adjusted by means of an eccentric cam 9, whereby the cylinder pressure is maintained at a predetermined pressure. |
