Patent ID: 11890721
Assignee: HITACHI-JOHNSON CONTROLS AIR CONDITIONING, INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 3:
4. The screw rotor processing method according to claim 1, wherein
when a rotation angle to be corrected at a position with a rotation angle θi on the reference lead is dθi, a distance at a position in a Z-direction as an axial direction is Zi, the lead correction amount is dP, and the reference lead is P0, the lead correction amount dP is obtained by the following equation (Expression 1):, [
          
            Expression
            ⁢
            
              
            
            ⁢
            1
          
          ]
        
        ⁢
        
          
        
      
    
    
      
        
      
    
  
  
    
      
        
          dP
          =
          
            
              
                2
                ⁢
                
                  π
                  ⁡
                  
                    (
                    
                      
                        Z
                        
                          i
                          +
                          1
                        
                      
                      -
                      
                        Z
                        i
                      
                    
                    )
                  
                
              
              
                
                  (
                  
                    
                      θ
                      
                        i
                        +
                        1
                      
                    
                    +
                    
                      d
                      ⁢
                      
                        
                      
                      ⁢
                      
                        θ
                        
                          i
                          +
                          1
                        
                      
                    
                  
                  )
                
                -
                
                  (
                  
                    
                      θ
                      i
                    
                    +
                    
                      d
                      ⁢
                      
                        
                      
                      ⁢
                      
                        θ
                        i
                      
                    
                  
                  )
                
              
            
            -
            
              P
              0
            
          
        
        ⁢
        
          

        
        ⁢
        
          
            i
            =
            0
          
          ,
          1
          ,
          2
          ,
          …
          ⁢
          
            
          
          ,
        
      
    
    
      
        (
        
          Expression
          ⁢
          
            
          
          ⁢
          1
        
        )
      
    
  

where an index i indicates an order of a measurement point at which the lead error with respect to the reference lead at the Z-direction position of the rotor groove portion has been measured, and “i=0” corresponds to an origin of the rotation angle or the Z-direction position.