Air bearing articulated shaft and floating module configuration for a small rotary compressor

Abstract

An apparatus for mounting a plurality of rotary compressors with minimal mechanical tolerances, wherein each of the compressors imparts axial forces on the structures with which they are mounted. The mounting apparatus includes an articulated shaft that rotationally couples and axially decouples the impeller wheels of the rotary compressors. The articulated shaft interoperates with compressors configured in a back-to-back configuration and, in addition, may be coupled to a motor. The articulated shaft and the impeller wheels may be supported by air bearings. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

What is claimed is:  
     
         1 . An apparatus comprising: 
 a plurality of rotary compressors, each compressor having at least one impeller wheel; and    an articulated shaft that rotationally couples and axially decouples at least one impeller wheel from each of said plurality of rotary compressors.    
     
     
         2 . The apparatus of  claim 1  wherein said plurality of rotary compressors are mounted in back-to-back orientation.  
     
     
         3 . The apparatus of  claim 2  further comprising a motor coupled to said articulated shaft.  
     
     
         4 . The apparatus of  claim 1  wherein a splined coupling connects at least two segments of said articulated shaft.  
     
     
         5 . The apparatus of  claim 3  wherein a splined coupling connects said articulated shaft with at least one shaft of said motor.  
     
     
         6 . The apparatus of  claim 1  wherein said articulated shaft comprises at least three independent pieces.  
     
     
         7 . The apparatus of  claim 1  further comprising: 
 an air bearing supporting each of said impeller wheels.  
 
     
     
         8 . The apparatus of  claim 1  further comprising: 
 at least one foil thrust air bearing supporting at least one of said impeller wheels.  
 
     
     
         9 . The apparatus of  claim 8  wherein said foil thrust bearing further comprises: 
 an underspring member mounted between a thrust bearing surface and a compliant foil member.  
 
     
     
         10 . The apparatus of  claim 1  further comprising: 
 a radial air bearing supporting the articulated shaft.  
 
     
     
         11 . The apparatus of  claim 10  further comprising: 
 a motor shaft; and  
 a coupling on the inside diameter of said radial air bearing that engages a complimentary coupling on said motor shaft and connects said articulated shaft to said motor shaft.  
 
     
     
         12 . The apparatus of  claim 1  further comprising: 
 a plurality of articulated shafts that rotationally couple and axially decouple at least two back-to-back mounted rotary compressor impeller wheels.  
 
     
     
         13 . The apparatus of  claim 12  further comprising: 
 radial air bearings supporting said articulated shafts; and  
 air bearings supporting said impeller wheels.  
 
     
     
         14 . The apparatus of  claim 12  wherein each of said rotary compressors comprises one stage of a multi-stage compression system.  
     
     
         15 . A system comprising: 
 a plurality of rotary compressors, each having at least one impeller wheel; and    a multi-piece shaft that rotationally couples an impeller wheel from each of said compressors and permits relative axial movement of said impeller wheels.    
     
     
         16 . The system of  claim 15  further comprising: 
 splined couplings connecting a plurality of segments of said multi-piece shaft.  
 
     
     
         17 . The system of  claim 16  further comprising: 
 radial air bearings supporting said multi-piece shaft; and  
 foil thrust air bearings supporting said impeller wheels.  
 
     
     
         18 . The system of  claim 15  wherein said system is a device that generates electricity.  
     
     
         19 . The system of  claim 15  wherein said system is an integrated turbogenerator.  
     
     
         20 . A method for rotationally driving a compound machine comprising the steps of: 
 rotationally coupling two or more rotating elements of the compound machine to permit relative axial translation between said rotating elements; and    rotationally coupling said rotating elements to a driving shaft of the compound machine.    
     
     
         21 . The method of  claim 20  wherein said rotating elements are impeller wheels of rotary compressors.  
     
     
         22 . The method of  claim 20  wherein said step of rotationally coupling two or more rotating elements of the compound machine comprises coupling said elements with an articulated shaft.  
     
     
         23 . The method of  claim 22  further comprising coupling said articulated shaft to a motor.  
     
     
         24 . The method of  claim 22  further comprising connecting at least two segments of said articulated shaft through a splined coupling.  
     
     
         25 . The method of  claim 22  further comprising connecting said articulated shaft with a motor shaft via a splined coupling.  
     
     
         26 . The method of  claim 20  wherein said step of rotationally coupling two or more rotating elements of the compound machine comprises coupling said at least two rotating connectors through an articulated connector.  
     
     
         27 . The method of  claim 21  further comprising mounting said rotary compressors in back-to-back orientation.  
     
     
         28 . The method of  claim 27  further comprising supporting said impeller wheels with an air bearing.  
     
     
         29 . The method of  claim 21  further comprising supporting said impeller wheels with a foil thrust air bearing.  
     
     
         30 . The method of  claim 29  further comprising mounting an underspring member between a thrust bearing surface and an aerofoil portion of said foil thrust bearing.  
     
     
         31 . The method of  claim 22  further comprising supporting said articulated shaft by a radial air bearing.  
     
     
         32 . The method of  claim 31  further comprising connecting said articulated shaft to a motor shaft by engaging a coupling on the inside diameter of said radial air bearing with a complimentary coupling on said motor shaft.  
     
     
         33 . The method of  claim 20  wherein a the step of rotationally coupling two or more rotating elements of the compound machine comprises coupling at least two pairs of impeller wheels from back-to-back mounted rotary compressors using a plurality of articulated shafts.  
     
     
         34 . The method of  claim 22  further comprising the steps of: 
 supporting said articulated shaft by radial air bearings; and  
 supporting impeller wheels from a plurality of rotary compressors on air bearings.  
 
     
     
         35 . The method of  claim 34  wherein each of said rotary compressors comprises one stage of a multi-stage compression system.  
     
     
         36 . The method of  claim 21  further comprising mounting said rotary compressors within a device that generates electricity.  
     
     
         37 . The method of  claim 21  further comprising mounting said rotary compressors for use with a turbogenerator.  
     
     
         38 . A turbogenerator comprising: 
 a plurality of rotary compressors; and    means for rotationally coupling and axially decoupling at least one impeller wheel from each of said plurality of rotary compressors.    
     
     
         39 . The turbogenerator of  claim 36  wherein said means for rotationally coupling also couples said impeller wheels to a motor shaft.  
     
     
         40 . The turbogenerator of  claim 36  further comprising: 
 means for mounting said impeller wheels.  
 
     
     
         41 . The turbogenerator of  claim 36  further comprising: 
 means for supporting said means for rotationally coupling.  
 
     
     
         42 . The turbogenerator of  claim 36  wherein each of said rotary compressors comprises one stage of a multi-stage compression system.  
     
     
         43 . An apparatus comprising: 
 a rotating shaft;    a first rotating element;    a first coupling rotationally securing the first rotating element to the rotating shaft while permitting relative axial movement between the first rotating element and the rotating shaft;    a second rotating element; and    a second coupling rotationally securing the second rotating element to the rotating shaft while permitting relative axial movement between the first rotating element and the rotating shaft.    
     
     
         44 . The apparatus of  claim 43  wherein at least one of said first or second rotating elements is an impeller wheel from a rotary compressor and said apparatus is an integrated turbogenerator.  
     
     
         45 . The apparatus of  claim 43  wherein both the first and second rotating elements are rotating elements of rotary compressors.  
     
     
         46 . The apparatus of  claim 45  wherein the rotary compressors are mounted in back-to-back orientation.  
     
     
         47 . The apparatus of  claim 43  further comprising a motor coupled to the rotating shaft.  
     
     
         48 . The apparatus of  claim 43  further comprising a turbine coupled to the rotating shaft.  
     
     
         49 . The apparatus of  claim 43  wherein the first coupling is a multifaceted coupling.  
     
     
         50 . The apparatus of  claim 43  wherein the first coupling is a splined coupling.  
     
     
         51 . The apparatus of  claim 43  further comprising an air bearing supporting the first rotating element.  
     
     
         52 . The apparatus of  claim 43  further comprising foil thrust air bearings supporting the first and second rotating elements.  
     
     
         53 . The apparatus of  claim 52  wherein said foil thrust air bearings each comprise an underspring member mounted between a thrust bearing surface and compliant foil member.  
     
     
         54 . The apparatus of  claim 43  further comprising a radial air bearing supporting said rotating shaft.  
     
     
         55 . The apparatus of  claim 54  wherein said rotating shaft is connected to a motor shaft through a coupling on the inside diameter of said radial air bearing that engages a complimentary coupling on said motor shaft.  
     
     
         56 . The apparatus of  claim 43  wherein the first and second rotating elements are components of two back-to-back mounted rotary compressors.  
     
     
         57 . The apparatus of  claim 43  wherein the apparatus is a turbogenerator.  
     
     
         58 . The apparatus of  claim 57  wherein the first and second rotating elements are components of rotary compressors in a multi-stage compression system.  
     
     
         59 . A method for mounting components in a compound machine comprising: 
 rotationally coupling a rotating shaft to a first rotating element using a coupling that permits relative axial movement between the first rotating element and the rotating shaft; and    rotationally coupling a second rotating element to the rotating shaft using a coupling that permits relative axial movement between the second rotating element and the rotating shaft.    
     
     
         60 . The method of  claim 59  wherein at least one of the first or second rotating elements is an impeller wheel from a rotary compressor.  
     
     
         61 . The method of  claim 59  wherein both the first and second rotating elements are components of rotary compressors that are mounted in opposite directions.  
     
     
         62 . The method of  claim 59  further comprising coupling the rotating shaft to a motor.  
     
     
         63 . The method of  claim 59  further comprising mating a splined surface of the rotating shaft with a complimentary surface of a motor shaft.  
     
     
         64 . The method of  claim 59  further comprising mounting said first and second rotating elements on air bearings.  
     
     
         65 . The method of  claim 59  further comprising supporting said rotating shaft by a radial air bearing.  
     
     
         66 . A compound machine comprising: 
 a rotating shaft;    a first rotating component;    a second rotating component;    a first coupling rotationally securing the first rotating component to an intermediate coupling while permitting axial translation of the first rotating component relative to the intermediate coupling; and    a second coupling rotationally securing the second rotating component to the intermediate coupling while permitting axial translation of the second rotating component relative to the intermediate coupling.    
     
     
         67 . The compound machine of  claim 66  wherein said first and second rotating elements are impeller wheels of rotary compressors.  
     
     
         68 . The compound machine of  claim 66  further comprising: 
 a motor shaft rotationally coupled to, and axially decoupled from, said second rotating component by said second coupling.  
 
     
     
         69 . The compound machine of  claim 68  wherein said second coupling is a splined coupling.  
     
     
         70 . The compound machine of  claim 68  wherein said second coupling has a multifaceted interface.  
     
     
         71 . The compound machine of  claim 66  wherein said compound machine is a turbomachine.  
     
     
         72 . The compound machine of  claim 68  further comprising radial air bearings and foil thrust air bearings.  
     
     
         73 . The compound machine of  claim 68  wherein said compound machine is an integrated turbogenerator.  
     
     
         74 . A turbogenerator having a motor generator driven by a turbine wheel, the improvement comprising: 
 a multi-stage rotary compressor comprising a plurality of rotating components and a structure that rotationally couples but does not axially couple said plurality of rotating components.    
     
     
         75 . The turbogenerator of  claim 74  wherein each of said plurality of rotating components are compressor impeller wheels.  
     
     
         76 . The turbogenerator of  claim 74  wherein said structure is an articulated shaft.  
     
     
         77 . The turbogenerator of  claim 74  wherein each of said plurality of rotating components are supported by foil thrust air bearings and said structure is supported by radial air bearings.  
     
     
         78 . The turbogenerator of  claim 74  wherein at least two stages of said multi-stage rotary compressor are mounted back-to-back.  
     
     
         79 . The turbogenerator of  claim 74  wherein said multi-stage rotary compressor has at least four stages mounted in back-to-back pairs.  
     
     
         80 . A rotationally-driven compound machine comprising: 
 means for coupling two or more rotating elements of the compound machine to permit relative axial translation between said rotating elements; and    means for rotationally coupling said rotating elements to a driving shaft of the compound machine.    
     
     
         81 . The rotationally-driven compound machine of claim  80 , wherein said rotating elements are impeller wheels, further comprising means for supporting said impeller wheels.  
     
     
         82 . The rotationally-driven compound machine of claim  80 , further comprising means for supporting said means for coupling two or more rotating elements.