Pumping system for evacuating gas from a plurality of chambers and method for controlling the pumping system

Abstract

A pumping system for evacuating gas from a plurality of chambers, includes at least one turbomolecular pump, at least two fore-vacuum pumps, at least one connection conduit extending between the at least two fore-vacuum pumps. and at least one transverse constriction for at least one of reducing and regulating gas flow.

What is claimed is: 
     
         1 . A pumping system for evacuating gas from a plurality of chambers, comprising at least one turbomolecular pump; at least two fore-vacuum pumps; at least one connection conduit extending between the at least two fore-vacuum pumps; and at least one transverse constriction for at least one of reducing and regulating gas flow. 
     
     
         2 . A pumping system according to  claim 1 , wherein the at least one transverse constriction is formed as an adjustable constriction. 
     
     
         3 . A pumping system according to  claim 1 , comprising a further turbomolecular pump constructively identical to the at least one turbomolecular pump. 
     
     
         4 . A pumping system according to  claim 1 , wherein at least one transverse constriction is formed as one of throttle orifice, throttle valve, and gas flow controller. 
     
     
         5 . A pumping system according to  claim 1 , wherein the at least one transverse constriction is formed as one of regulated and switchable valves. 
     
     
         6 . A pumping system according to  claim 1 , comprising a plurality of transverse constrictions switchingly arranged one of seriesly and parallel to each other. 
     
     
         7 . A pumping system according to  claim 1 , wherein there is provided a superordination process control for regulating the at least one transverse constriction. 
     
     
         8 . A pumping system according to  claim 1 , wherein a device for measuring one of actual vacuum and gas flow rate is provided at least at one of a point of at least one chamber of the plurality of chambers, in the at least one conduit, and pump connections provided to that end. 
     
     
         9 . A pumping system according to  claim 1 , wherein the at least one turbomolecular pump is formed as an exhaust pressure-dependent pump. 
     
     
         10 . A pumping system according to  claim 1 , wherein the pumping system is designed for evacuating gas from a plurality of chambers comprising at least two chambers connected with each other. 
     
     
         11 . A pumping system according to  claim 10 , wherein one of the at least two fore-vacuum pumps is located immediately adjacent to one of the at least two chambers. 
     
     
         12 . A pumping system according to  claim 1 , comprising a plurality of turbomolecular pumps, wherein at least one of the fore-vacuum pumps is arranged in front of at least one of the turbomolecular pumps. 
     
     
         13 . A pumping system according to  claim 1 , comprising a plurality of turbomolecular pumps, and wherein the at least two fore-vacuum pumps are arranged, at least one off together and separately, in front of one of a part of the turbomolecular pumps and all of the turbomolecular pumps. 
     
     
         14 . A pumping system according to  claim 1 , comprising a plurality of turbomolecular pumps, and wherein at least one of the plurality of turbomolecular pumps has two inlets. 
     
     
         15 . A method of controlling a pumping system for evacuating gas from a plurality of chambers, comprising at least one turbomolecular pump; at least two fore-vacuum pumps; at least one connection conduit extending between the at least two fore-vacuum pumps; and at least one transverse constriction for at least one of reducing and regulating gas flow, the method comprising the steps of measuring one of vacuum and gas flow rate at at least one of a point of at least one chamber, in the at least one conduit, and pump connections provided to that end; and using the at least one of measured variables for controlling the at least one transverse constriction.