Yoke of Rotating Electric Machine and Method of Manufacturing the Same

Abstract

A rotating electric machine includes a bearing; a rotating shaft supported via the bearing; and a yoke with a bearing support portion formed on a yoke bottom surface. The bearing support portion houses the bearing, and on a cylinder front-end portion of the bearing support portion, integrally formed is a ring-shaped flange portion that is inclined toward an inner radial side so as to prevent the bearing from coming off one end side.

1 . A rotating electric machine, comprising:
 a bearing;   a rotating shaft supported via the bearing; and   a yoke with a bearing support portion formed on a yoke bottom surface, wherein:   bearing support portion houses the bearing, and   on a cylinder front-end portion of the bearing support portion, integrally formed is a ring-shaped flange portion that is inclined toward an inner radial side so as to prevent the bearing from coming off one end side.   
   
   
       2 . The rotating electric machine according to  claim 1 , wherein:
 the bearing support portion is formed by burring an edge of a through-hole open in the yoke bottom surface by use of a burring punch, and   the flange portion is formed by locating, at the time of burring, a front end portion of the burring punch on a base end side a distance from the cylinder front-end portion of the bearing support portion.   
   
   
       3 . The rotating electric machine according to  claim 1 , wherein a step portion formed on the rotating shaft prevents the bearing from coming off another end side. 
   
   
       4 . The rotating electric machine according to  claim 1 , wherein a shield ring attached to the yoke bottom surface prevents the bearing from coming off another end side. 
   
   
       5 . A method for manufacturing a yoke, comprising:
 forming a through-hole that is open in a yoke bottom surface and a cylindrical bearing support portion by burring an edge of the through-hole using a burring punch, wherein:   the burring punch is located on a base end side at a distance from a cylinder front-end portion of the bearing support portion so as to form a ring-shaped flange portion inclined toward an inner radial side on the cylinder front-end portion of the bearing support portion.   
   
   
       6 . A method for manufacturing a rotating electric machine, comprising:
 supporting a rotating shaft via a bearing; and   manufacturing a yoke according to  claim 5 , wherein:
 the bearing support portion houses the bearing, and 
 the ring-shaped flange portion prevents the bearing from coming off one end side. 
   
   
   
       7 . The method according to  claim 6 , further comprising the step of forming a step portion on the rotating shaft to prevent the bearing from coming off another end side. 
   
   
       8 . The method according to  claim 6 , further comprising the step of attaching a shield ring to the yoke bottom surface to prevent the bearing from coming off another end side. 
   
   
       9 . The rotating electric machine according to  claim 2 , wherein a step portion formed on the rotating shaft prevents the bearing from coming off another end side. 
   
   
       10 . The rotating electric machine according to  claim 2 , wherein a shield ring attached to the yoke bottom surface prevents the bearing from coming off another end side. 
   
   
       11 . A yoke comprising:
 a bearing support portion formed on a yoke bottom surface, wherein on a cylinder front-end portion of the bearing support portion, integrally formed is a ring-shaped flange portion that is inclined toward an inner radial side.   
   
   
       12 . The yoke according to  claim 11 , wherein:
 the bearing support portion is formed by burring an edge of a through-hole open in the yoke bottom surface by use of a burring punch, and   the flange portion is formed by locating, at the time of burring, a front end portion of the burring punch on a base end side at a distance from the cylinder front-end portion of the bearing support portion.