PURPOSE: To reduce the fluctuation of vibration characteristics by loading a metal plate with a pressurizing force in accordance with the bending angle and eliminating the generation of excessive residual stress.
CONSTITUTION: In a leaf spring forming device by which the metal plate 4 is pressurized to a lower die 2 having a prescribed curvature by a roller 5, a piezoelectric element 7 is used as a pressing force source for the roller 5. The bending angle of the metal plate 4 is detected by a rotary encoder, etc., and the applying voltage of the piezoelectric element 7 is controlled according to a detecting signal and the pressuring force of the roller 5 at the time of bending is regulated. Since the slight pressuring force loaded on the metal plate is precisely controlled, no fluctuation is generated in the bent shape.
KONO AKIOMI
MORI KENJI
IMAI SATOMITSU
SAKAGOSHI SEIJI
TAKEUCHI YOSHINORI
NAKAJIMA YASUYUKI
