| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a device and method for forming a gear which can accurately form a gear having external teeth and spline grooves while holding the pressure required for the forming small and ensuring die durability. <P>SOLUTION: A device 1 for forming a gear comprises a die 3, a mandrel 4, a punch 5, a die sleeve 6 and an inner die 7, and forms a gear by conducting enclosed die cold forging together with stamping. In the device 1 for forming a gear, the lower end insertion part 42 of the mandrel 4 is arranged in a through hole 81 of a ringlike material 80, and the ringlike material 80 is pressurized against the die sleeve 6 and the inner die 7 by the punch 5, thereby, forming a shape of the gear having external teeth by causing a part of the ringlike material 80 to flow into an external tooth formation hole 31 of the die 3. The mandrel 4 is made to descend to stamp spline grooves on the inner peripheral side portion of the ringlike material 80 by a punching blade 411 of the mandrel 4 and a punch receptacle blade 61 of the die sleeve 6. <P>COPYRIGHT: (C)2012,JPO&INPIT |
