| 摘要 |
<p>A switching valve for the selective connection of each of a plurality of measuring locations with a manometer has a first valve body mechanically connected to the manometer and a second valve body rotatable with respect to the manometer, the second body having a radial control bore connected constantly with the measuring bore of the manometer. In order to attain tight closure between the two valves without the use of seat valves, the second valve has a spherical zone into which opens a control bore. In the other part are a plurality of packing bodies, the number of which corresponds to the number of measuring locations, each of the packing bodies having a central bore in a plane perpendicular to the axis of the first valve, each packing body have an annular sealing surface which is in constant contact with the spherical zone. A chamber including the spherical zone can be connected outside of the packing surfaces to a vent tank.</p> |
