Opposed screw compressor with staggered screw rotor

Abstract

A rotor for use in a fluid machine includes a rotor shaft, a first portion supported by the rotor shaft and having a plurality of first lobes, and a second portion supported by the rotor shaft having a plurality of second lobes. The plurality of first lobes at an inwardly facing end of the first portion is arranged at a stagger angle relative to the plurality of second lobes at an inwardly facing end of the second portion. The stagger angle is greater than zero.

What is claimed is: 
     
         1 . A rotor for use in a fluid machine comprising:
 a rotor shaft;   a first portion supported by the rotor shaft and having a plurality of first lobes;   a second portion supported by the rotor shaft having a plurality of second lobes, wherein the plurality of first lobes arranged at an inwardly facing end of the first portion are arranged at a stagger angle relative to the plurality of second lobes arranged at an inwardly facing end of the second portion, the stagger angle being greater than zero.   
     
     
         2 . The rotor of  claim 1 , wherein the stagger angle is less than an angular pitch of the plurality of first lobes. 
     
     
         3 . The rotor of  claim 2 , wherein the stagger angle is equal to between 10% and 90% of the angular pitch. 
     
     
         4 . The rotor of  claim 2 , wherein the stagger angle is equal to between 25% and 75% of the angular pitch. 
     
     
         5 . The rotor of  claim 1 , wherein each of the plurality of first lobes has a first lobe shape at the inwardly facing end of the first portion and each of the plurality of second lobes has a second lobe shape at the inwardly facing end of the second portion, wherein the first lobe shape and the second lobe shape are substantially identical. 
     
     
         6 . The rotor of  claim 1 , wherein the first portion and the second portion are fixed for rotation with the rotor shaft. 
     
     
         7 . The rotor of  claim 1 , wherein the first portion and the second portion are rotatable about the rotor shaft. 
     
     
         8 . The rotor of  claim 1 , wherein the first portion is rotatable independently from the second portion. 
     
     
         9 . The rotor of  claim 1 , wherein the fluid machine further comprises another rotor including:
 another rotor shaft;   another first portion supported by the another rotor shaft and having a plurality of first lobes; and   another second portion supported by the another rotor shaft having a plurality of second lobes, wherein the plurality of first lobes arranged at an inwardly facing end of the another first portion are arranged at another stagger angle relative to the plurality of second lobes arranged at an inwardly facing end of the another second portion, the another stagger angle being greater than zero.   
     
     
         10 . The rotor of  claim 9 , wherein the stagger angle and the another stagger angle are different. 
     
     
         11 . A rotor for use in a fluid machine comprising:
 a rotor shaft;   a first portion supported by the rotor shaft and having a plurality of first lobes;   a second portion supported by the rotor shaft having a plurality of second lobes, wherein the plurality of first lobes arranged at an inwardly facing end of the first portion aligned with the plurality of second lobes arranged at an inwardly facing end of the second portion.   
     
     
         12 . The rotor of  claim 11 , wherein an angle formed between the plurality of first lobes arranged at the inwardly facing end of the first portion and the plurality of second lobes arranged at an inwardly facing end of the second portion within 5% of an angular pitch of the plurality of first lobes. 
     
     
         13 . The rotor of  claim 12 , wherein the angle is zero degrees. 
     
     
         14 . The rotor of  claim 11 , wherein each of the plurality of first lobes has a first lobe shape at the inwardly facing end of the first portion and each of the plurality of second lobes has a second lobe shape at the inwardly facing end of the second portion, wherein the first lobe shape and the second lobe shape are substantially identical. 
     
     
         15 . The rotor of  claim 11 , wherein the first portion and the second portion are fixed for rotation with the rotor shaft. 
     
     
         16 . The rotor of  claim 11 , wherein the first portion and the second portion are rotatable about the rotor shaft. 
     
     
         17 . The rotor of  claim 11 , wherein the first portion is rotatable independently from the second portion. 
     
     
         18 . The rotor of  claim 11 , wherein the fluid machine further comprises another rotor including:
 another rotor shaft;   another first portion supported by the another rotor shaft and having a plurality of first lobes; and   another second portion supported by the another rotor shaft having a plurality of second lobes, wherein the plurality of first lobes arranged at an inwardly facing end of the another first portion are aligned with the plurality of second lobes arranged at an inwardly facing end of the another second portion.   
     
     
         19 . The rotor of  claim 18 , wherein a first angle of formed between the plurality of first lobes arranged at the inwardly facing end of the first portion and the plurality of second lobes arranged at an inwardly facing end of the second portion is equal to a second angle of formed between the plurality of first lobes arranged at the inwardly facing end of the another first portion and the plurality of second lobes arranged at an inwardly facing end of the another second portion.