Vacuum pump system with a liquid ring pump

摘要

Disclosed is a vacuum pump fitted with a liquid mechanical pump for pumping out gas, for example against the atmospheric pressure. According to the invention, the liquid of the liquid mechanical pump (6) is an inert fluid; the liquid mechanical pump (6) works together with a membrane-type primary pump (9) and is provided, on the inlet side, with a suction valve (3) controlled so as to open only when the temperature of the liquid mechanical pump (6) exceeds a lower threshold value.