Powder metal internal gear rolling process

Abstract

A method for forming an internal gear is provided comprising providing a powder metal preform workpiece, supporting the workpiece about its periphery, and roll forming said workpiece to produce a set of densified gear teeth of a predefined dimension.

1 . A method for forming an internal gear is provided comprising:
 providing a powder metal preform workpiece;   supporting the workpiece about its periphery; and   roll forming said workpiece to produce a set of densified gear teeth of a predefined dimension.   
     
     
         2 . The method according to  claim 1  wherein said powder metal workpiece comprises a toothed preform. 
     
     
         3 . The method according to  claim 1  wherein said powder metal workpiece comprises a non-toothed preform. 
     
     
         4 . The method according to  claim 1  wherein said set of densified gear teeth are any one of a straight or helical form. 
     
     
         5 . The method according to  claim 1  wherein said roll forming includes either axial or radial feeding. 
     
     
         6 . The method according to  claim 1  wherein said roll forming includes a single rolling tool. 
     
     
         7 . The method according to  claim 1  wherein said roll forming includes a plurality of rolling tools. 
     
     
         8 . A tool set for forming an internal gear comprising:
 a holding fixture for supporting a powder metal workpiece around the periphery of said workpiece; and   a rolling tool for roll forming an inner surface of said workpiece to produce a set of densified gear teeth of a predefined dimension.   
     
     
         9 . The tool set according to  claim 8  wherein said rolling tool is configured to apply to said set of densified gear teeth either straight or helical teeth. 
     
     
         10 . The tool set according to  claim 8  wherein said rolling tool is fed either axially or radially. 
     
     
         11 . The tool set according to  claim 8  comprising a single rolling tool. 
     
     
         12 . The tool set according to  claim 8  comprising a plurality of rolling tools.