Concentric bearing and seal arrangement of a shaft in a hydrogen system

Abstract

A gas compressor that compresses a gas in a fuel cell system includes a shaft having first and second ends, a first bearing rotatably supporting the shaft at the first end and a second bearing rotatably supporting the shaft between the first and second ends. A sealing arrangement is concentric with the second bearing to inhibit migration of the gas between compartments of the compressor. The gas compressor can be a compressor, blower, pump or supercharger or turbo compressor that transports the gas.

1 . A gas compressor to compress a gas in a fuel cell system, comprising: 
 a shaft having a first end and a second end;    a first bearing rotatably supporting said shaft at said first end;    a second bearing rotatably supporting said shaft between said first and second ends; and    a sealing arrangement concentric with said second bearing to inhibit migration of said gas between compartments of said compressor.    
   
   
       2 . The gas compressor of  claim 1  further comprising a compressor impeller fixed for rotation with said shaft and rotatably driven by said shaft in a compressor compartment to compress said gas.  
   
   
       3 . The gas compressor of  claim 1  further comprising an electric motor disposed in a motor compartment and engaged with said shaft to rotatably drive said shaft.  
   
   
       4 . The gas compressor of  claim 1  wherein said compartments include a compressor compartment and a motor compartment, wherein said sealing arrangement inhibits migration of said gas from said compressor compartment into said motor compartment.  
   
   
       5 . The gas compressor of  claim 4  wherein said first end of said shaft and said first bearing are disposed within said motor compartment.  
   
   
       6 . The gas compressor of  claim 4  wherein said second bearing is disposed within said motor compartment.  
   
   
       7 . The gas compressor of  claim 1  Wherein said sealing arrangements comprises a barrier-gas sealing system.  
   
   
       8 . A gas compressor for compressing a hydrogen-containing gas for use in a fuel cell system, comprising: 
 a shaft extending between a motor compartment and a compressor compartment and having first and second ends;    a first bearing rotatably supporting said shaft at said first end within said motor compartment;    a second bearing rotatably supporting said shaft between said first and second ends;    a sealing arrangement concentric with said second bearing to inhibit migration of said hydrogen-containing gas between said motor compartment and said compressor compartment.    
   
   
       9 . The gas compressor of  claim 8  wherein said second bearing is disposed within said motor compartment.  
   
   
       10 . The gas compressor of  claim 8  further comprising a compressor impeller fixed for rotation with said shaft and rotatably driven by said shaft within said compressor compartment to compress said hydrogen-containing gas.  
   
   
       11 . The gas compressor of  claim 10  further comprising a suction inlet to enable intake of said hydrogen-containing gas into said compressor compartment and a discharge outlet to enable discharge of said hydrogen-containing gas to said fuel cell system.  
   
   
       12 . The gas compressor of  claim 8  further comprising an electric motor disposed in said motor compartment and engaged with said shaft to rotatably drive said shaft.  
   
   
       13 . The gas compressor of  claim 8  wherein said sealing arrangement comprises a barrier-gas sealing system.  
   
   
       14 . A fuel cell system, comprising: 
 a fuel cell providing an exhaust gas; and    an exhaust gas compressor to compress said exhaust gas from said fuel cell and recirculate said exhaust gas to said fuel cell, said compressor comprising:    a shaft having first and second ends;    a first bearing rotatably supporting said shaft at said first end;    a second bearing rotatably supporting said shaft between said first and second ends; and    a sealing arrangement concentric with said second bearing to inhibit migration of said exhaust gas between compartments of said compressor.    
   
   
       15 . The fuel cell system of  claim 14  further comprising a compressor impeller fixed for rotation with said shaft and rotatably driven by said shaft in a compressor compartment to compress said exhaust gas.  
   
   
       16 . The fuel cell system of  claim 14  further comprising an electric motor disposed in a motor compartment and engaged with said shaft to rotatably drive said shaft.  
   
   
       17 . The fuel cell system of  claim 14  wherein said compartments include a compressor compartment and a motor compartment, wherein said sealing arrangement inhibits migration of said exhaust gas from said compressor compartment into said motor compartment.  
   
   
       18 . The fuel cell system of  claim 17  wherein said first end of said shaft and said first bearing are disposed within said motor compartment.  
   
   
       19 . The fuel cell system of  claim 17  wherein said second bearing is disposed within said motor compartment.  
   
   
       20 . The fuel cell system of  claim 14  wherein said sealing arrangements comprises a barrier-gas sealing system.