Forging device

Abstract

A forging device produces a forged product in which a protrusion is formed on a base plate. The forging device has a die with a molding hole and a punch to be driven into the molding hole. A protrusion molding cavity is formed in a bottom surface of the molding hole or a tip end surface of the punch in the die. A base plate molding portion is formed between the tip end surface of the punch and the bottom surface of the molding hole. A burr molding portion is formed between the tip end portion outer peripheral side surface of the punch and the inner peripheral side surface of the molding hole. The inner peripheral side surface of the molding hole is formed by an inclined surface that approaches an axis as it advances toward the pressing direction of the punch.

1 . A forging device for producing a forged product in which a protrusion is formed on a base plate, comprising:
 a die having a molding hole; and   a punch to be driven into the molding hole,   wherein a protrusion molding cavity is formed in at least one of a bottom surface of the molding hole of the die and a tip end surface of the punch,   wherein a base plate molding portion is formed between the tip end surface of the punch and the bottom surface of the molding hole,   wherein a burr molding portion is formed between a tip end portion outer peripheral side surface of the punch and an inner peripheral side surface of the molding hole, and   wherein the inner peripheral side surface of the molding hole is formed by an inclined surface which is inclined with respect to an axis and approaches the axis toward a pressing direction of the punch.   
     
     
         2 . The forging device as recited in  claim 1 ,
 wherein a chamfered portion is formed at an internal corner portion between the inner peripheral side surface and the bottom surface of the molding hole.   
     
     
         3 . The forging device as recited in  claim 1 ,
 wherein the tip end portion outer peripheral side surface of the punch is formed by an inclined surface which is inclined with respect to the axis and approaches the axis toward the pressing direction of the punch, and   wherein an inclination angle of the tip end portion outer peripheral side surface of the punch with respect to the axis is formed to be equal to or less than an inclination angle of the inner peripheral side surface of the molding hole with respect to the axis.   
     
     
         4 . The forging device as recited in  claim 1 ,
 wherein a chamfered portion is formed at an external corner portion between the tip end portion outer peripheral side surface and the tip end surface of the punch.   
     
     
         5 . The forging device as recited in  claim 1 ,
 wherein an external corner portion between the tip end portion outer peripheral side surface and the tip end surface of the punch is arranged at a position closer to the axis than the internal corner portion between the inner peripheral side surface and the bottom surface of the molding hole.   
     
     
         6 . The forging device as recited in  claim 1 ,
 wherein the protrusion molding cavity is constituted by a fin molding cavity for molding a fin of a heat sink.   
     
     
         7 . A forging method for producing a forged product in which a protrusion is formed on a base plate, comprising:
 a step of setting a forging material in a molding hole of a die formed by an inclined surface in which an inner peripheral side surface of a molding hole is inclined with respect to an axis and approaches the axis toward an inner portion of the molding hole; and   a step of pressurizing the forging material by driving a punch into the molding hole;   wherein in the step of pressurizing the forging material, a protrusion is formed by a protrusion molding cavity formed on at least one of a bottom surface of the molding hole of the die and a tip end surface of the punch,   wherein a base plate is molded by a base plate molding portion formed between the tip end surface of the punch and the bottom surface of the molding hole, and   wherein a burr is formed by a burr molding portion formed between a tip end portion outer peripheral side surface of the punch and the inner peripheral side surface of the molding hole.   
     
     
         8 . A production method of a forged product for producing a forged product in which a protrusion is formed on a base plate, comprising:
 a step of setting a forging material in a molding hole of a die formed by an inclined surface in which an inner peripheral side surface of the molding hole is inclined with respect to an axis and approaches the axis towards the inner portion of the molding hole; and   a step of pressurizing the forging material by driving a punch into the molding hole;   wherein in the step of pressurizing the forging material, a protrusion is formed by a protrusion molding cavity formed on at least one of a bottom surface of the molding hole of the die and a tip end surface of the punch,   wherein a base plate is molded by a base plate molding portion formed between a tip end surface of the punch and the bottom surface of the molding hole, and   wherein a burr is formed by a burr molding portion formed between a tip end portion outer peripheral side surface of the punch and the inner peripheral side surface of the molding hole.