Rotation shaft, feeding device, motor and manufacturing method for rotation shaft

Abstract

A rotation shaft includes a spiral groove for feeding which is formed on the outer peripheral face of the rotation shaft and a plurality of fine recessed parts which is formed on a flank surface of the spiral groove. The rotation shaft may be manufactured by a spiral groove forming step which forms a spiral groove on an outer peripheral face of the rotation shaft and a roughening step which forms a plurality of fine recessed parts on the flank surface of the spiral groove by using a first abrasive medium whose size is set to be capable of reaching to the flank surface. The rotation shaft may be preferably applied to a feeding device and a motor.

1 . A rotation shaft comprising: 
 a spiral groove for feeding which is formed on an outer peripheral face of the rotation shaft; and    a plurality of fine recessed parts which is formed on a flank surface of the spiral groove.    
   
   
       2 . The rotation shaft according to  claim 1 , wherein the plurality of fine recessed parts is formed on the flank surface in a dispersed state.  
   
   
       3 . The rotation shaft according to  claim 2 , wherein the plurality of fine recessed parts is formed on the flank surface by abrasion processing.  
   
   
       4 . The rotation shaft according to  claim 3 , wherein the plurality of fine recessed parts is formed on the flank surface by using a medium for barrel for the abrasion processing.  
   
   
       5 . The rotation shaft according to  claim 1 , wherein raw material of the rotation shaft is nonferrous metal.  
   
   
       6 . A feeding device comprising: 
 a rotation shaft which is formed with a spiral groove for feeding on an outer peripheral face of the rotation shaft, the spiral groove of the rotation shaft being provided with a plurality of fine recessed parts which is formed on a flank surface of the spiral groove;    a movable body which is provided with a rack part engaging with the rotation shaft and is linearly driven in an axial direction by rotation around an axial line of the rotation shaft; and    lubricant which is coated on the spiral groove of the rotation shaft.    
   
   
       7 . The feeding device according to  claim 6 , wherein the plurality of fine recessed parts formed on the flank surface of the spiral groove of the rotation shaft is formed in a dispersed state.  
   
   
       8 . The feeding device according to  claim 7 , wherein the plurality of fine recessed parts is formed on the flank surface by abrasion processing.  
   
   
       9 . The feeding device according to  claim 8 , wherein the plurality of fine recessed parts is formed on the flank surface by using a medium for barrel for the abrasion processing.  
   
   
       10 . The feeding device according to  claim 6 , wherein raw material of the rotation shaft is nonferrous metal.  
   
   
       11 . The feeding device according to  claim 6 , wherein the rack part is made of resin.  
   
   
       12 . A motor comprising: 
 a rotation output shaft which is formed with a spiral groove for feeding on an outer peripheral face of the rotation shaft, the spiral groove of the rotation output shaft being provided with a plurality of fine recessed parts which is formed on a flank surface of the spiral groove; and    a main motor body which drives the rotation output shaft to rotate around an axial line of the rotation output shaft.    
   
   
       13 . The motor according to  claim 12 , wherein the plurality of fine recessed parts formed on the flank surface of the spiral groove of the rotation output shaft is formed in a dispersed state.  
   
   
       14 . The motor according to  claim 13 , wherein the plurality of fine recessed parts is formed on the flank surface by abrasion processing.  
   
   
       15 . The motor according to  claim 14 , wherein the plurality of fine recessed parts is formed on the flank surface by using a medium for barrel for the abrasion processing.  
   
   
       16 . The motor according to  claim 12 , wherein raw material of the rotation output shaft is nonferrous metal.  
   
   
       17 . A manufacturing method for a rotation shaft comprising: 
 a spiral groove forming step which forms a spiral groove on an outer peripheral face of the rotation shaft; and    a roughening step which forms a plurality of fine recessed parts on a flank surface of the spiral groove by using a first abrasive medium whose size is set to be capable of reaching to the flank surface.    
   
   
       18 . The manufacturing method for a rotation shaft according to  claim 17 , wherein raw material of the rotation output shaft is nonferrous metal.  
   
   
       19 . The manufacturing method for a rotation shaft according to  claim 17 , wherein the roughening step uses mixed media of the first abrasive medium and a second abrasive medium whose size is larger than the size of the first abrasive medium.  
   
   
       20 . The manufacturing method for a rotation shaft according to  claim 17 , further comprising a deburring step which removes burr from the rotation shaft by using a second abrasive medium whose size is larger than the size of the first abrasive medium.