Vacuum pump system

Abstract

A vacuum pump system comprises two vacuum pumps which are connected to each other. In order to create vacuum pump system of a more compact size, the connection between the two vacuum pumps is performed via connection elements directly attached to the pump housing and forming connection sites, and the outlet flange of the upper pump is placed directly on the inlet flange of the lower pump without thereby causing a transmission of larger forces or moments.

1 . A vacuum pump system, comprising
 a first vacuum pump comprising a pump inlet and a pump outlet,   a second vacuum pump comprising a pump inlet and a pump outlet,   the pump outlet and/or the pump inlet of the second vacuum pump being fluidically connected, with the aid of flanges, to the pump inlet of the first vacuum pump,   wherein a first and a second pump housing are mechanically connected to each other on at least three connection sites so as to allow for force transmission, at least two of said connection sites being flange-independent.   
     
     
         2 . The vacuum pump system according to  claim 1 , wherein each connection site comprises two mutually confronting connection elements. 
     
     
         3 . The vacuum pump system according to  claim 1 , wherein at least two connection sites are arranged outside of the surfaces of said flanges. 
     
     
         4 . The vacuum pump system according to  claim 1 , wherein at least two flange-independent connection sites are configured or arranged in a manner enabling them, in combination, to transfer 25%, and preferably at least 40%, of the forces and moments occurring in operation. 
     
     
         5 . The vacuum pump system according to  claim 1 , wherein at least three connection sites are flange-independent. 
     
     
         6 . The vacuum pump system according to  claim 5 , wherein the connection of the pump inlet to the pump outlet is substantially exclusively a fluidic connection. 
     
     
         7 . The vacuum pump system according to  claim 6 , wherein no force-locking connection, and particularly no screw connection, is provided between the pump inlet and the pump outlet. 
     
     
         8 . The vacuum pump system to according  claim 1 , wherein the connection elements comprise projections extending from a housing wall. 
     
     
         9 . The vacuum pump system according to  claim 1 , wherein mutually confronting, mutually connected connection elements of a connection site comprise two mutually plane-parallel support faces. 
     
     
         10 . The vacuum pump system according to  claim 9 , wherein the support faces of at least two connection elements of a vacuum pump are arranged in one plane, preferably in the plane of a flange-abutment face. 
     
     
         11 . The vacuum pump system according to  claim 1 , wherein the connection sites comprise holding elements, said holding elements preferably being integrated into said projections or being provided separately. 
     
     
         12 . The vacuum pump system according to  claim 2 , wherein the connection elements of at least one connection site are displaceable relative to each other. 
     
     
         13 . The vacuum pump system according to  claim 2 , wherein a spacer element is provided to compensate for level differences between mutually confronting connection elements, particularly between their abutment faces. 
     
     
         14 . The vacuum pump system according to  claim 2 , wherein the connection elements are at least partially arranged in the region of side walls of the pump housing and/or in the region of support flanges. 
     
     
         15 . The vacuum pump system according to  claim 2 , wherein an adapter element arranged between two vacuum pumps connected to each other, for connection of connection elements which are not confronting each other, one of said vacuum pumps optionally comprising only one connection site which is formed as a flange. 
     
     
         16 . The vacuum pump system according to  claim 15 , wherein, for receiving the weight of an upper vacuum pump, said adapter element comprises at least two adapter feet. 
     
     
         17 . The vacuum pump system according to  claim 15 , wherein, for receiving the weight of an upper vacuum pump, said adapter element comprises at least three, preferably four adapter feet, to the effect that the inlet flange preferably remains stress-free. 
     
     
         18 . The vacuum pump system according to  claim 1 , comprising more than two vacuum pumps.