The structure of the machine is a three-roller symmetrical type, and the upper roller is vertically lifted and moved in the central symmetrical position of the two lower rollers, and is obtained by the screw-threaded worm drive, and the two lower rollers are rotated, and the output gear and the lower roller of the reducer are passed. Gear meshing provides torque to the rolled sheet. The disadvantage of this machine is that the end of the plate needs to be pre-bent by means of other equipment.