Fuel cell compressor system

Abstract

The invention provides a fuel cell compressor system that comprises a motor, including a motor shaft driven by the motor; a drive housing at least partially surrounding the motor shaft; a first gear set driven by the motor shaft; a carrier torque tube driven by the first gear set; and an impeller. The impeller includes an impeller shaft driven by the second gear set, so that the impeller shaft is configured to rotate at a speed greater than motor speed. Embodiments of the invention may also include a first bearing supporting the carrier torque tube and a second bearing supporting the impeller shaft. Embodiments of the invention may also include a seal system.

1 . A fuel cell compressor system, comprising:
 a motor, including a motor shaft driven by the motor;   a drive housing at least partially surrounding the motor shaft;   a first gear set driven by the motor shaft;   a carrier torque tube driven by the first gear set, the carrier torque tube configured to rotate at motor speed;   a second gear set driven by the motor shaft; and   an impeller, including an impeller shaft driven by the second gear set, the impeller shaft configured to rotate at a speed greater than motor speed.   
     
     
         2 . A system in accordance with  claim 1 , including a first bearing disposed between the tube and the drive housing for at least partially supporting the tube, and a second bearing disposed between the impeller shaft and the tube for at least partially supporting the impeller shaft. 
     
     
         3 . A system in accordance with  claim 1 , wherein the first gear set comprises a spur gear or a planet gear carrier. 
     
     
         4 . A system in accordance with  claim 1 , wherein the second gear set comprises a helical gear or a spur gear. 
     
     
         5 . A system in accordance with  claim 2 , wherein the second bearing includes an outer race and an inner race, wherein the rate of rotation of the outer race is at substantially the same speed as the rate of rotation of the carrier torque tube. 
     
     
         6 . A system in accordance with  claim 5 , wherein the rate of rotation of the inner race is at least partially offset by the rate of rotation of the outer race. 
     
     
         7 . A system in accordance with  claim 2 , wherein the carrier torque tube and the impeller shaft rotate in the same direction. 
     
     
         8 . A system in accordance with  claim 2 , wherein the first bearing comprises a sealed greased bearing. 
     
     
         9 . A system in accordance with  claim 2 , wherein the second bearing comprises a sealed greased bearing. 
     
     
         10 . A system in accordance with  claim 1 , wherein the motor comprises a low-speed motor. 
     
     
         11 . A system in accordance with  claim 2 , wherein the first bearing rotates at motor speed. 
     
     
         12 . A system in accordance with  claim 2 , wherein the second bearing rotates at the difference between motor speed and impeller shaft speed. 
     
     
         13 . A system in accordance with  claim 1 , further comprising a seal system for preventing contamination of fluid in the system 
     
     
         14 . A system in accordance with  claim 13 , wherein the seal system is disposed between the impeller shaft and the drive housing. 
     
     
         15 . A system in accordance with  claim 13 , wherein the seal system is disposed between the impeller shaft and the carrier torque tube. 
     
     
         16 . A system in accordance with  claim 13 , wherein the seal system is disposed between the carrier torque tube and the drive housing. 
     
     
         17 . A system in accordance with  claim 13 , wherein the seal system comprises:
 a first seal;   a second seal; and   a drain located in the drive housing for draining contaminants from the system.   
     
     
         18 . A system in accordance with  claim 17 , wherein the drain is located between the first seal and the second seal. 
     
     
         19 . A system in accordance with  claim 17 , wherein a first side of the first seal is pressurized and a second side of the first seal is vented to the atmosphere, thereby creating a pressure gradient. 
     
     
         20 . A system in accordance with  claim 17 , further comprising a wave spring for forcing the first seal against the drive housing. 
     
     
         21 . A system in accordance with  claim 17 , wherein the first seal comprises one of phenolics, ceramics, glass, or silicon nitride. 
     
     
         22 . A system in accordance with  claim 17 , wherein the second seal comprises rubber. 
     
     
         23 . A fuel cell compressor system, comprising:
 a motor, including a motor shaft driven by the motor;   a drive housing at least partially surrounding the motor shaft;   a first gear set driven by the motor shaft;   a carrier torque tube driven by the first gear set, the carrier torque tube configured to rotate at a first speed;   a first bearing disposed between the carrier torque tube and the drive housing for at least partially supporting the tube;   a first impeller driven by the carrier torque tube at a first speed for imparting fluid flow through a first stage of the system;   a second gear set driven by the motor shaft;   an impeller shaft driven by the second gear set, the impeller shaft configured to rotate at a second speed;   and a second bearing disposed between the impeller shaft and the tube for at least partially supporting the impeller shaft.   a second impeller driven by the impeller shaft at a second speed for imparting fluid flow through a second stage of the system.   
     
     
         24 . A system in accordance with  claim 23 , further comprising a diverter valve configured to allow fluid to bypass the second stage of the system. 
     
     
         25 . A system in accordance with  claim 23 , wherein the second speed is greater than the first speed. 
     
     
         26 . A system in accordance with  claim 23 , wherein the first bearing and second bearing include sealed greased bearings. 
     
     
         27 . A fuel cell compressor system, comprising:
 a motor, including a motor shaft driven by the motor;   a gear set driven by the motor shaft, the gear set disposed within a drive housing at least partially surrounding the motor shaft;   an impeller, including an impeller shaft driven by the motor shaft wherein the impeller shaft is configured to be driven by the gear set at a speed greater than motor speed;   a compressor housing surrounding the impeller;   a carrier torque tube at least partially surrounding the motor shaft;   a first bearing disposed between the impeller shaft and the carrier torque tube for at least partially supporting the impeller shaft;   a second bearing disposed between the carrier torque tube and the compressor housing for at least partially supporting the carrier torque tube,   wherein the first and second bearings are each configured to rotate at a speed less than motor speed.