PURPOSE: To obtain a press structure which is capable of absorbing an eccentric load which is a reaction to a ram when working by press, by interposing a pair of opposed buffer members having a spherical surface, between the ram and a punch holder.
CONSTITUTION: In case when reaction force of F>(f) has operated against a shank axis (a)-(a), a shank 3 is turned in the direction as indicated with an arrow centering around the supporting point of a contact point B of a die 9 of a punch 6a and the axis (a)-(a) side. Accordingly, a projecting spherical surface 3a of the shank 3 goes down microscopically against a lower hollowed spherical surface 2b of a buffer member 2. As the spherical surface 3a goes down microscopically, the member 2 goes down microscopically, as well, and is inclined to turn by being drawn along with turning of the spherical surface 3a. In this case, since the diameter of a spherical surface 2a is smaller than the diameter of the spherical surface 2b, a microscopic space is generated between a projecting spherical surface 1a of the tip of a ram and the spherical surface 2a, and the member 2 is turned microscopically. Subsequently, the spherical surface 1a and the spherical surface 2a, and the spherical surface 2b and the spherical surface 3a are returned to the normal contact state by a fall of the ram 1 and also a controlling action of repulsion compressive force of a return spring 7b.
JPH0811000 | PUNCHING METHOD IN PRESS |
TAKAHASHI MASAOMI