Cold Rolling of Zigzag-Toothed Gears : Improvement of Material Flow by Arranging the Teeth in Zigzags

Abstract

A new type of cylindrical gear which is called a zigzag-toothed gear is proposed.This type of gear has the same cross-sectional profile as a conventional spur gear, and a tooth trace which is arranged in zigzags on a cylindrical surface. A specigl configuration, such as a zigzag-toothed gear, improves the material flow in gear rolling so that there is a more precise form of tooth. In rolling this type of gear, the axial flow of material, which seems to be indispensable to complete the gear rolling but never appears in the rolling of conventional gears, is induced. Additionally, this type of gear has the advantage of maintaining good conditions for the lubricant and the ability to support some thrust load.