Roll forming device for forming variable thickness plate

A roll forming device for forming a variable thickness plate, comprising:

• both-side stand frames that are disposed at a left side and a right side on a process base at a predetermined distance from each other and in which a sliding groove is formed at a center portion in an up and down direction;
• a lower forming roll unit in which a lower forming roll is fixed on a lower rotation shaft such that both end portions are rotatably disposed on a lower sliding block that is fixed to a lower portion of each sliding groove on the both-side stand frames;
• an upper forming roll unit in which an upper forming roll is fixed on an upper rotation shaft such that both end portions are rotatably disposed at an upper sliding block that is disposed on each sliding groove of the both-side stand frames to be slidably moved in an up and down direction above the lower forming roll unit;
• a forming roll gap adjustment unit that adjusts an initial gap between the lower forming roll and the upper forming roll, wherein a worm wheel and a worm gear are operated in an adjustment block of each upper portion of the both-side stand frames and an adjustment screw that is screw-engaged to a center of the worm wheel in an up and down direction adjusts an up-down direction position of the both-side upper sliding blocks;
• and
• a spring unit that is disposed between the adjustment screw and the upper sliding block within each sliding groove of the both-side stand frames, absorbs a forming reaction force that is applied to the upper forming roll according to a thickness variation of a plate that is to be formed, and simultaneously maintains a forming pressure of the upper forming roll within a predetermined range,
• wherein the spring unit includes:
• a support block that is fixed to an upper surface of the upper sliding block in each sliding groove of the both-side stand frames;
• a spring housing that is fixedly engaged with an upper portion of the support block, an upper surface of which is opened, and that forms a receiving space portion together with the support block;
• a retainer that is disposed at an upper portion at an inside of the receiving space portion of the spring housing, an upper end of which is connected to a lower end of the adjustment screw through a rotation body, and a spring guider is formed at a center of a lower surface thereof;
• and
• a plurality of disk springs that are disposed inside of the receiving space portion of the spring housing to be engaged with the spring guider of the retainer in a crisscross manner and offer elastic force between the retainer and the support block.