PROBLEM TO BE SOLVED: To compact a cylindrical green compact having a constriction part at the middle part in the axial direction of the outer circumferential face so as to be drawn out from dies to the axial direction.;SOLUTION: An internal die 20 having a die hole 25 forming the outer circumferential face shape of the cavity C of a green compact 1 is composed of a plurality of split dies 21 split to a horizontal direction orthogonal to an axial direction, and the respective split dies 21 are installed on punch holders 13 via sliders 27 so as to be freely separable. The sliders 27 are made to approach each other by a tension spring 28, and, ordinarily, the split dies 21 are made into a matched state. After the powder is compressed by upper and lower punches 35, 15, the external die 10 around the internal die 20 is relatively lowered, cam bars 31 are pushed into a space between rollers 29 mounted at the sliders 27, the split dies 21 are split, and a green compact can be drawn out from the inside of the split dies 21 to an axial direction.;COPYRIGHT: (C)2010,JPO&INPIT
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