摘要 |
A vacuum pump comprising a closed housing, an elastometric diaphragm in the form of a cup therein, said diaphragm having a rim, said rim being sealed into the wall of the housing, said diaphragm dividing the housing into two chambers one including the interior of the diaphragm and the other being at the exterior thereof, a constant vacuum outlet for the latter chamber and a pair of check valves which are substantially the same but reversed for the chamber at the interior of the diaphragm.
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