CPC F04B 37/14 (2013.01) [F04B 41/06 (2013.01); F04B 49/007 (2013.01); F04D 13/12 (2013.01); F04D 19/042 (2013.01); F04D 25/16 (2013.01); F04D 27/005 (2013.01)] | 15 Claims |
1. A vacuum exhaust system for evacuating a plurality of vacuum chambers, said vacuum exhaust system comprising:
a plurality of turbo vacuum pumps configured for evacuating said plurality of vacuum chambers;
a plurality of chamber valves for isolating or connecting said plurality of turbo vacuum pumps with said plurality of vacuum chambers;
a plurality of branch channels each connected to a corresponding exhaust of said plurality of turbo vacuum pumps;
a main channel formed from a confluence of said branch channels and configured to provide a fluid communication path between said plurality of branch channels and a booster vacuum pump, said booster vacuum pump being configured to evacuate said main channel;
a backing vacuum pump connected to an exhaust of said booster vacuum pump;
a plurality of bypass channels for providing a fluid communication path between at least some of said plurality of vacuum chambers and the backing vacuum pump; wherein said plurality of bypass channels each comprise a backing valve configured to be switched between two states comprising a first state that prevents gas in the bypass channel from passing through the backing valve to reach the backing vacuum pump and a second state that allows gas in the bypass channel to pass through the backing valve to reach the backing vacuum pump; and
a plurality of connecting valves, each connecting valve positioned between a respective bypass channel and the booster vacuum pump and configured to be switched between two states comprising a first state that prevents gas in the respective bypass channel from passing through the connecting valve to reach the booster vacuum pump and a second state that allows gas in the respective bypass channel to pass through the connecting valve to reach and be pumped by the booster vacuum pump.
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