BENDING METHOD OF LAMINATED STEEL PLATE

摘要

PURPOSE:To prevent plate shifting and mouth opening by pulling and elongating the other plate in the stage of bending a laminated steel plate sandwiching a resin layer toward one plate side. CONSTITUTION:The laminated steel plate 3 is sandwiched between a punch 1 and a movable die 6. Bending of one end of the plate 3 by a stationary die 2 is executed by ascending of the punch 1 and retreating of the die 6. Resistance parts 8 which apply resistance to the steel plate 5 in contact with the forming surface 7 of the die 2 are provided to said surface by forming projections, etc. and therefore the shifting of the plate 5 is controlled and only the steel plate 4 is permitted to shift. The plate 5 is therefore pulled by the parts 8 and is elongated in the bending direction until bending is completed. The pressing force acts also toward the inside in the thickness direction thereof. The lengths at the front ends of the flanges are thus unified and the mouth opening is prevented by the above-mentioned method.