Manufacturing method of bearing device

Abstract

A method for manufacturing a bearing device includes steps: providing a hollow mold, then injecting a feedstock of powder and molten binder into the mold under pressure, thus forming a desired perform of a cylindrical body and a desired perform of a cover; separating the binder from the desired perform of the body and the desired perform of the cover; sintering the desired perform of the body and the desired perform of the cover, thereby forming the body and the cover; and mounting the cover on the body, thereby forming the bearing device.

What is claimed is: 
     
         1 . A method for manufacturing a bearing device comprising:
 providing a hollow mold, then injecting a feedstock of powder and molten binder into the mold under pressure, thus forming a desired perform of a body and a desired perform of a cover, the desired perform of the body defining an axial hole, a guiding groove at an outer side wall of the desired perform of the body, and a bore in a middle portion of the desired perform of the body to communicate the axial hole and the guiding groove;   separating the binder from the desired perform of the body and the desired perform of the cover;   sintering the desired perform of the body and the desired perform of the cover, thereby forming the body and the cover; and   mounting the cover on the body, thereby forming the bearing device.   
     
     
         2 . The method of  claim 1 , wherein polyethylene is used as a material of the binder of the feedstock. 
     
     
         3 . The method of  claim 2 , wherein the binder of the feedstock is removed by debinding or extraction. 
     
     
         4 . The method of  claim 1 , wherein a precision machining operation is performed on the desired perform of the body and the desired perform of the cover after the sintering process. 
     
     
         5 . The method of  claim 1 , wherein a sintering operation is performed on the cover and the body together after the mounting process. 
     
     
         6 . The method of  claim 1 , wherein the cover comprises a top circular wall and an annular wall extending downward from a periphery of the top circular wall. 
     
     
         7 . The method of  claim 6 , wherein the cover defines a central hole and comprises a guiding portion extending downwards from an inner edge of the central hole. 
     
     
         8 . The method of  claim 1 , wherein a bottom of the body defines a through groove to divide the bottom of the body into two walls, inner surfaces of the walls forming a first storing room communicating the axial hole and the through groove. 
     
     
         9 . The method of  claim 8 , wherein the bottom of the body defines an annular undercut to have a guiding surface, the guiding surface forming a second storing room to communicate the bottom end of the guiding groove to the through hole of the bottom of the body. 
     
     
         10 . The method of  claim 9 , wherein a diameter of the guiding surface of the body gradually decreases from top to bottom.