Research and application on structural design of a novel electromagnetic sheet thickness adaptive roll forming auxiliary device

To meet forming requirements for sheets of varying thicknesses, the roll gap size must be adjusted regularly during the roll forming process. Traditional manual adjusting methods have low efficiency and high mistake rates. To address this issue, we present a unique electromagnetic sheet-thickness-adaptive roll forming auxiliary device that is essentially an adjustable-stiffness spring device with an electromagnetic spring and a disc spring functioning in parallel. Finite element analysis was utilized to improve the structural dimensions of the device, and a performance test was carried out to guarantee that it operated smoothly. The stiffness of the devices may be quickly adjusted by changing the current. The experimental peak value of the electromagnetic force of an electromagnetic spring under a particular current differed by no more than 5.7% from the simulation value. The application results of the proposed device with a roll forming machine show that when forming a given sheet thickness, the forming force of the roll forming machine in the adaptive forming mode is stable to within 10% of the forming force in the traditional forming mode, achieving the goal of adaptive roll forming. As a result, an adjustable stiffness spring device can solve the roll gap and forming force adaption problems encountered during the roll forming process.