METHOD AND DEVICE FOR PRECISION COLD FORGING OF GEAR PART

摘要

PURPOSE: To reduce the forging process of a gear part by obtaining the product shape prior to reverse taper forming at one time cold forging and prolong the life thereof by reducing the bearing pressure of a forging die. ;CONSTITUTION: A flange part 14 is formed on the outer circumferential surface of a boss part 15, a gear part which has a gear teeth part 16 at the intermediate part between the boss part 15 and flange part 14, is formed cold forging only. At that time, when representing A₀ for an area of end face prior to forging of the boss part 15 and A₁ for an area of end face after forging of the boss part, an area reduction rate R=(A₀-A₁)/A₀ is in range of 28-41%. By this method, the distribution of material flow between boss part and gear teeth part is not biased either to excessive increase of working bearing pressure and excessive lowering of teeth part filling efficiency, the work is forged.;COPYRIGHT: (C)1995,JPO