PURPOSE: To provide a cold-forging apparatus and a cold-forging method, by which a product can be minimized by making an effective area in the toothed part of the toothed product large and such a toothed product can simply be manufactured in a low cost. ;CONSTITUTION: In this apparatus, a lower die 1 forming the toothed part 1a in the inner peripheral part, a lower punch 2 inserted so as to be vertically moved in this lower die 1 and an upper punch 3 vertically driven while facing to this lower punch 2 from the upper part, are provided. Further, an energizing means 4 elastically energized in the condition of the upper end part 2a of the lower punch 2 projected from the upper surface 1b of the lower die 1 is arranged. On the outer peripheral part of the upper punch 3, a toothed part 3a inserted with a prescribed small gap Δ into the toothed part 1a at the inner peripheral part of the lower die 1 is formed. The lower end surface 3b of the toothed part 3a in this upper punch 3 is formed as ascending sloping state to the outer part.;COPYRIGHT: (C)1995,JPO
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