Apparatus for full-enclosed die forging

Abstract

An apparatus for full-enclosed die forging for forging a material into a workpiece having concavities on its opposite end surfaces including a first die provided on a stationary frame. A second die is provided on a movable frame which moves toward and away from the stationary frame to come into and out of contact with the first die. A first punch on the stationary frame and a second punch on the movable frame plunge into a cavity formed by the closed pair of these dies from the opposite sides. The first die is movable in a forging direction in a die housing provided on the stationary frame and is forced to the second die by a first spring member in the die housing. A plurality of die engaging members are housed in the die housing, and are disposed at the surrounding of the first die and are biased into the die housing. The second die is attached to a slide member provided slidably in the forging direction on the movable frame and is forced together with the slide member to the first die by a second spring member. A thrusting portion on the slide member is provided for thrusting the die engaging members inside the die housing to engage the die engaging members with the first and the second dies after the first die and the second die are closed to each other in the process of the advancement of the movable frame. A differential mechanism causes the slide member to move forward according to the advancement movement of the movable frame slower than the movable frame after the die engaging members are engaged with the first and the second dies. With the first punch fixed and the second punch on the movable frame side advancing integrally with the movable frame, this allows the first and second dies to advance integrally with the slide member to move toward the first punch at a speed slower than that of the second punch.

Dependencies are inferred from the claim text.