Integrated cold forging method and apparatus therefor for weight of monolithic eccentric yoke for steering

摘要

The present invention relates to a method for weight reduction cold forging of an integrated eccentric yoke for steering and a device thereof. The present invention provides a first forging die (10) comprising a first upper mold (110) and a first lower mold (120) having a first punch (140) from the cylindrical material (A) by the first punch. A lower cylindrical portion B1 having a constant outer diameter and a tapered surface B2 gradually extending from the lower cylindrical portion B1 are formed, and the lower cylindrical portion forms a constant outer diameter from an upper portion of the tapered surface B2. A first forging step S100 for forming a primary molded body B having an upper cylindrical portion B3 having an outer diameter larger than that of (B1); The second forging mold including the second upper mold 210 having the second punch 240 and the second lower mold 220 of the primary molded body B manufactured in the first forging step S100. The outer wall C3 curved to one side is formed from the planar portions C1 and C2 formed parallel to each other in the upper cylindrical portion B3 by the second punch 240 at 20, and protrudes from the rear wall portion ( A second forging step (S200) of molding the secondary molded body C so that C4) is formed; Hole processing to form a punch insertion hole (C5) having a surface tooth (C6) at the inlet at a constant depth from the upper surface of the secondary molded body (C) formed in the second forging step (S200) in the axial center Step S300; The third upper mold 310 and the third lower portion having the punch insertion hole C3 of the secondary molded body C having the punch insertion hole C5 having the third punch 340 formed therein in the hole processing step S300. Tertiary molded body (D) having a punching hole (D1) in which the inner diameter is larger than the punch insertion hole (C5) by punching with a third punch 340 in the third forging die (30) consisting of a mold (320) A third forging step (S400) to form a; Heat treatment step (S450) to remove the bur (bur) of the tertiary molded body (D) formed in the third step (S400) and heat treatment to produce an eccentric yoke; integral eccentric for lightweight and durable steering including Provide York