Spindle motor and method of manufacturing the same

Abstract

A spindle motor is formed so as to support a pivot of a rotor by a pair of open bearings. The open bearings thus constructed will be less expensive and simple structures, so that a manufacturing cost thereof is reduced compared to a conventional spindle motor using a pair of ball bearings with shields. Accordingly, a low-cost spindle motor can be provided.

What is claimed is:  
     
         1 . A spindle motor for supporting a rotor by a pair of ball bearings, wherein said pair of ball bearings is open ball bearings of which both sides are open.  
     
     
         2 . A spindle motor according to  claim 1 , wherein said pair of open ball bearings is disposed in such a manner that extending parts formed in one side of outer rings or inner rings abut each other.  
     
     
         3 . A spindle motor according to  claim 1  or  2 , wherein said pair of open ball bearings is disposed in a shaft rotatable spindle motor in which said inner rings rotate together with said rotor.  
     
     
         4 . A spindle motor according to any one of  claims 1  to  3 , wherein said pair of open ball bearings is disposed in a shaft fixed spindle motor in which said outer rings rotate together with said rotor.  
     
     
         5 . A method of manufacturing a spindle motor for supporting a rotor by a pair of ball bearings, said ball bearing being open ball bearings both sides of which are opened, said method comprising: 
 a bearing washing process of cleaning said open ball bearings;    a grease filling process of filling grease in said open ball bearings cleaned in said bearing washing process; and    a bearing mounting process of mounting said open ball bearings filled with the grease in said grease filling process on said spindle motor;    these processes being sequentially performed upon assembly process of said spindle motor.