| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an effective solution for a problem where a metal powder and a metal filler are stuck between a die and a lower punch to result in an increasing die sliding resistance and accordingly die move is disabled such that a gear manufactured in a powder metallurgy process can be molded without trouble. <P>SOLUTION: An outer diameter side chamfering/molding part 7 is arranged at the outer diameter side of the tip of the lower punch 2 having an inner diameter side chamfering/molding part 6 at the tip. Further, a powder removing groove 8 having a sharp edge and a discharge groove 9 communicating with the powder removing groove are arranged at the outer circumferential surface of the sliding part 2b of the lower punch, and an lower end of the discharge groove 9 arranged at a tooth bottom of a meshing tooth 2a is made to run to a lower punch small diameter part 2c below the sliding part 2b. <P>COPYRIGHT: (C)2013,JPO&INPIT |
