COLD-FORGING METAL MOLD AND COLD-FORGING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a cold-forging metal mold capable of easily and surely performing the stable molding of holes, and forming a deep hole having a deep dimension longer than the projection dimension of a punch pin.;SOLUTION: A cold-forging metal mold comprises: a male die 3, equipped with a punch pin 1 and a sleeve 2 which is larger in diameter than the punch pin 1 and a hole part 20 with the insertion of the punch pin 1; and a female die 5, having a first hole 51 to store a workpiece W and a second hole 52 which communicates with the depth of the first hole 51 and is smaller in diameter than the first hole 51, to press the workpiece W in the first hole 51 with a tip end reference face 21 of the sleeve 2, and to form a long hole J corresponding a predetermined projection dimension S in the workpiece W by projecting the punch pin 1 from the tip end reference face 21 up to the predetermined projection dimension S, and the workpiece W is pressed with the tip end reference face 21 in the state where the predetermined projection dimension S of the punch pin 1 is held to force the workpiece W into the second hole 52, so that a columnar space K is formed in the workpiece W on the tip 11 side of the punch pin 1 to form a deep hole Q with a depth dimension H longer than the predetermined projection dimension S.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2017,JPO&INPIT