Gear burnisher method and apparatus

Abstract

In a gear burnishing system having burnishing gear positions arranged around a subject gear at its center, a burnishing gear is formed as a scraper gear retained on a shaft rotationally by a keyway formed in an inner bore of the scraper gear which is wider by a predefined gap than a corresponding key formed on the shaft such that the scraper gear can move angularly by a small amount for maximum contact on the subject gear. In a preferred embodiment, a number of scraper gears are arranged in a stack on the shaft. Both ends of each scraper gear are beveled along the peripheral edges to cause each tooth to be raked and to create knife blades and serve to trap debris. Each tooth is formed with equal blade angles and a recess with compound angles for debris entrapment. The scraper gears can be mounted with bearings for limited gimbal movement to assure following the subject gear.

1 . In a gear burnishing system having a plurality of burnishing gear positions arranged in a star pattern with a subject gear held in its geometric center, the improvement in which a burnishing gear is formed as a scraper gear axially retained in position on a shaft at at least one burnishing gear position, wherein the scraper gear is retained on the shaft rotationally by a keyway formed in an inner bore of the scraper gear which is wider by a predefined gap than a corresponding key formed on the shaft such that the scraper gear can move angularly by a small amount for maximum contact on the subject gear. 
   
   
       2 . The improvement for a burnishing gear according to  claim 1 , wherein a number of scraper gears are arranged in a stack retained on the shaft. 
   
   
       3 . The improvement for a burnishing gear according to  claim 2 , wherein the gear burnishing system has three burnishing gear positions at 4 o'clock, 8 o'clock, and 12 o'clock positions around the subject gear, and a stack of scraper gears is arranged at each of the 4 o'clock and 8 o'clock positions and a pressure gear is arranged at the 12 o'clock position. 
   
   
       4 . The improvement for a burnishing gear according to  claim 3 , wherein due to the stacks of scraper gears at the 4 o'clock and 8 o'clock positions, a subject gear will be subjected to a number of contacts equal to two times the number of gears per stack at each stack position. 
   
   
       5 . The improvement for a burnishing gear according to  claim 4 , wherein each stack has 3 scraper gears, and a subject gear will be subjected to six times the number of contacts as compared to a conventional burnishing gear system. 
   
   
       6 . The improvement for a burnishing gear according to  claim 2 , wherein both ends of each scraper gear are beveled along the peripheral edges in such a fashion as to cause the end condition of each tooth to be raked and to create knife blades, and the bevels cause peripheral gaps between the scraper gears in the stack which serve the function of trapping debris as they traverse the subject gear during the burnishing process. 
   
   
       7 . The improvement for a burnishing gear according to  claim 6 , wherein on each scraper gear, each tooth thereof has an angular surface formed as a scraper blade and an opposite angular surface formed with compound angled surfaces including an angle that is equal to the angle of the scraper blade and a recess that provides a gap needed for debris entrapment. 
   
   
       8 . The improvement for a burnishing gear according to  claim 6 , wherein the scraper gear is mounted on the shaft by bearings that provide for limited gimbal movement to assure that the burnishing action will follow a lead crown present on the subject gear. 
   
   
       9 . The improvement for a burnishing gear according to  claim 8 , wherein the scraper gear is mounted on opposite sides by a pair of spherical type bearings on the shaft. 
   
   
       10 . The improvement for a burnishing gear according to  claim 6 , wherein the scraper gear stacks are mounted on adjustable slides which can be adjusted then locked in place to adjust the center distance between them. 
   
   
       11 . A method for burnishing a subject gear using a scraper gear according to the improvement in  claim 1 .