Research on the mold release motion for spiral bevel gear forging

At present, spur bevel gears are mainly processed by forging, showing advantages of high processing efficiency, low processing cost and fine microstructure material. Spiral bevel gears, meanwhile, are widely generated by machining, including face-milling, face-hobbing, etc., in spite of the superiority identified of forged spiral bevel gears for years. The major hindrance originally lied in the manufacture of the mold, and along with the development of multi-axial machine tool, it is now no longer a problem. Accurate design of mold release motion (MRM) to avoid interference, however, remains a problem due to the fact that the tooth lengthwise of spiral bevel gear is not straight. To resolve this, this paper, through deriving the equation of the tooth surface, investigating algorithm for mold release motion interference and discussing the motion parameter presetting, proposes first a mold release motion analysis (MRMA) method for forging spiral bevel gear. Subsequently, based on the method, a computerized program is developed, in which the ideal mold release motion can be obtained through adjusting the recommended motion according to the mold release interference analysis. (C) 2017 Elsevier Ltd. All rights reserved.