Multi-stage hook and claw compressor assembly

Abstract

A multi-stage compressor system for compressing a working fluid includes a compressor housing and a drive unit configured to drive a first shaft and a second shaft. The first shaft defines a first axis of rotation and the second shaft defines a second axis of rotation, where the first axis is parallel to the second axis of rotation. The compressor system further includes a first airend and a second airend operable to receive and compress the working fluid. The first airend includes a first rotor configured to be driven by the first shaft and a second rotor configured to be driven by the second shaft. The second airend further compresses the working fluid received from the first airend, and includes a third rotor configured to be driven by the first shaft and a fourth rotor configured to be driven by the second shaft.

What is claimed is: 
     
         1 . A multistage air compressor configured to compress a working fluid, the two-stage air compressor comprising:
 a single compressor housing having a first airend and a second airend;   a drive unit configured to drive a first shaft and a second shaft, the first shaft defining a first axis of rotation and the second shaft defining a second axis of rotation, the first axis of rotation parallel to the second axis of rotation, the first shaft having a first end configured to be driven by the drive unit;   the first airend operable to receive and compress the working fluid, the first airend including a first rotor configured to be driven by the first shaft and a second rotor configured to be driven by the second shaft, the first rotor and the second rotor defining a first rotor pair;   the second airend operable to receive the working fluid from the first airend and further compress the working fluid, the second airend including a third rotor configured to be driven by the first shaft and a fourth rotor configured to be driven by the second shaft, the third rotor and the fourth rotor defining a second rotor pair,   wherein the first rotor and the third rotor are disposed at a center distance from the second rotor and the fourth rotor, respectively.   
     
     
         2 . The multistage air compressor of  claim 1 , wherein at least one of the first rotor pair or the second rotor pair is a conjugate pair. 
     
     
         3 . The multistage air compressor of  claim 1 , wherein at least one of a bore diameter of the first rotor or a bore diameter of the third rotor is equal to a bore diameter of the second rotor or a bore diameter of the fourth rotor, respectively. 
     
     
         4 . The multistage air compressor of  claim 1 , wherein at least one of a bore diameter of the first rotor or a bore diameter of the third rotor is different to a bore diameter of the second rotor or a bore diameter of the fourth rotor, respectively. 
     
     
         5 . The multistage air compressor of  claim 1 , wherein the bore diameter of the first rotor pair in the first airend is different than a bore diameter of the second rotor pair in the second airend. 
     
     
         6 . The multistage air compressor of  claim 1 , wherein a rotor profile of the first rotor pair is different than a rotor profile of the second rotor pair. 
     
     
         7 . The multistage air compressor of  claim 6 , wherein one of the rotor profile of the first rotor pair is a hook and claw rotor profile and the rotor profile of the second rotor pair has a lobe rotor profile. 
     
     
         8 . The multistage air compressor of  claim 6 , wherein the first rotor pair has a first rotor width, and second rotor pair has a second rotor width, and wherein the first rotor width is equal to the second rotor width. 
     
     
         9 . The multistage air compressor of  claim 1 , wherein the first rotor pair has a first rotor width, and second rotor pair has a second rotor width, and wherein the first rotor width is different from the second rotor width. 
     
     
         10 . The multistage air compressor of  claim 1 , wherein the compressor housing includes a partitioning wall configured to separate the first airend from the second airend. 
     
     
         11 . The multistage air compressor of  claim 1 , further comprising a timing gear assembly mounted on the first shaft and the second shaft, the timing gear assembly configured to synchronously drive the second shaft with respect to the first shaft. 
     
     
         12 . The multistage air compressor of  claim 1 , wherein the first airend has a first mass flow rate and a first volumetric flow rate, and the second airend has a second mass flow rate and a second volumetric flow rate, where the first mass flow rate and the second mass flow rate are equal to each other, and where the first volumetric flow rate is greater than the second volumetric flow rate. 
     
     
         13 . The multistage air compressor of  claim 1 , wherein the compressor housing defines a cooling channel disposed within inner side wall of the compressor housing configured to circulate a coolant between the first airend and the second airend and inhibit heat conduction between the first airend and the second airend. 
     
     
         14 . The multistage air compressor of  claim 1 , further comprising an intercooler disposed between the first airend and the second airend, the intercooler configured to cool the working fluid prior to entering the second airend. 
     
     
         15 . The multistage air compressor of  claim 1 , where a first inlet port of the first airend and a second inlet port of the second airend open synchronously to receive the working fluid. 
     
     
         16 . The multistage air compressor of  claim 1 , where a first inlet port of the first airend and a second inlet port of the second airend open asynchronously to receive the working fluid. 
     
     
         17 . A multistage fluid compressor system comprising:
 a hook and claw (HC) compressor assembly for configured to compress a working fluid, the HC compressor assembly including:
 a single compressor housing containing multiple stages that compress the working fluid, 
 a drive unit configured to drive a first shaft and a second shaft, the first shaft defining a first axis of rotation and the second shaft defining a second axis of rotation, the first axis of rotation parallel to the second axis of rotation, the first shaft having a first end configured to be directly driven by the drive unit, 
 a first airend housed in the compressor housing and operable to receive and compress the working fluid, the first airend including a first rotor configured to be driven by the first shaft and a second rotor configured to be driven by the second shaft, and 
 a second airend housed in the compressor housing and operable to receive the working fluid from the first airend and further compress the working fluid, the second airend including a third rotor configured to be driven by the first shaft and a fourth rotor configured to be driven by the second shaft; and 
 a cooling system configured to circulate a coolant between the first airend and the second airend and inhibit heat conduction between the first airend and the second airend. 
   
     
     
         18 . The multistage fluid compressor system of  claim 17 , wherein a rotor profile of the first rotor pair is different than a rotor profile of the second rotor pair. 
     
     
         19 . The multistage fluid compressor system of  claim 18  wherein the first rotor pair has a first rotor width, and second rotor pair has a second rotor width, and wherein the first rotor width is different from the second rotor width. 
     
     
         20 . A multistage air compressor configured to compress a working fluid, the two-stage air compressor comprising:
 a single compressor housing having a first airend and a second airend;   a drive unit configured to drive a first shaft and a second shaft, the first shaft defining a first axis of rotation and the second shaft defining a second axis of rotation, the first axis of rotation parallel to the second axis of rotation, the first shaft having a first end configured to be driven by the drive unit;   the first airend operable to receive and compress the working fluid, the first airend including a first rotor configured to be driven by the first shaft and a second rotor configured to be driven by the second shaft, the first rotor and the second rotor defining a first rotor pair;   the second airend operable to receive the working fluid from the first airend and further compress the working fluid, the second airend including a third rotor configured to be driven by the first shaft and a fourth rotor configured to be driven by the second shaft, the third rotor and the fourth rotor defining a second rotor pair,   wherein the first rotor and the third rotor are disposed at a center distance from the second rotor and the fourth rotor, respectively, and wherein the first rotor pair has a first rotor width, and second rotor pair has a second rotor width, and wherein the first rotor width is different from the second rotor width.