Patent ID: 8821147

Claim:
An extrusion die device comprising: a die holder including a first surface located at an inlet side of an extrusion raw material, a second surface located at an outlet side of a formed material, and a supporting hole penetrating from the first surface to the second surface; and a die assembly accommodated in the supporting hole, wherein the die assembly comprises: a male die including a core member having a projected portion, a core case holding the core member while disposing the projected portion close to the second surface; a female die including a body which includes an engagement groove engaging the core case of the male die disposed close to the first surface, and which engages the supporting hole, and a nesting member formed in an annular shape and accommodated in the body at a portion close to the first surface; and a cap member formed in a plate shape, disposed at a position closer to the first surface than from the male die, covering a portion of the core member, and connected to the core case, a space between the nesting member and the core member is defined as a molding hole allowing the extrusion raw material to pass therethrough, and wherein the supporting hole of the die holder is formed in a forwardly shrinking-shape toward the first surface, and an engagement portion formed in a tapered shape that matches the forwardly shrinking-shape of the supporting hole is provided on the body of the female die at a position close to the first surface.