| 摘要 |
<p>Pumping system for obtaining high vacuum comprising a primary pump (4) and a secondary pump (1), associated in series whereby the secondary pump draws in gas from a chamber (3) and comprising means (7) for starting the secondary pump (1) when the upstream pressure of the primary pump (4) descends below a value P1, characterized in that a passive tank (10), and an isolating valve (11) are inserted between the delivery side (12) of the secondary pump (1) and the inlet (13) of the primary pump (4) and in that it comprises control means (7) for closing the isolating valve (11) and stopping the primary pump (4) when the pressure of said passive tank (10) attains a value P2<P1 and for opening the isolating valve (11) and restarting the primary pump (4) when the pressure in said passive tank (10) again attains pressure P1.</p> |
