High vacuum ejector pump with automatic cut-in valve

Claim 1

A HIGH VACUUM EVACUATOR SYSTEM COMPRISING A PRIMARY VACUUM PUMP HAVING AN INLET AND AN OUTLET, A SUCTION CONDUIT ADAPTED TO BE PLACED IN COMMUNICATION WITH A DEVICE WHICH IS TO BE EVACUATED, AN EJECTOR PUMP INTERPOSED BETWEEN AND COMMUNICATING WITH SAID SUCTION CONDUIT AND SAID INLET OF SAID PRIMARY VACUUM PUMP FOR OPERATING IN SERIES WITH SAID PRIMARY VACUUM PUMP FOR CREATING IN SAID SUCTION CONDUIT A PRESSURE LOWER THAN THAT WHICH COULD BE ACHIEVED BY THE PRIMARY VACUUM PUMP ITSELF, VALVE MEANS OPERATIVELY CONNECTED TO SAID PUMPS AND HAVING A CLOSED POSITION CUTTING OFF COMMUNICATION BETWEEN SAID EJECTOR PUMP AND A SOURCE OF MOTIVE FLUID THEREFOR, SO THAT WHEN SAID VALVE MEANS IS IN ITS CLOSED POSITION SAID EJECTOR PUMP DOES NOT OPERATE, SAID VALVE MEANS AUTOMATICALLY RESPONDING TO ACHIEVEMENT OF A PREDETERMINED DEGREE OF VACUUM BY SAID PRIMARY VACUUM PUMP FOR SUBSTANTIALLY INSTANTEOUSLY MOVING FROM SAID CLOSED POSITION TO A FULLY OPEN POSITION RENDERING SAID EJECTOR PUMP SUBSTANTIALLY INSTANTANEOUSLY FULLY OPERATIVE, SO THAT SAID EJECTOR PUMP WILL THEN PROVIDE IN SAID SUCTION CONDUIT A LOWER PRESSURE THAN THAT ACHIEVED BY SAID PRIMARY VACUUM PUMP.