lThe machine adopts three-roller symmetrical structure with the upper roller moving vertically in the center between the two lower rollers, which is achieved through the drive of the screw, the net, the worm and the lead screw, the two lower rollers rotates, and provides the plate materials with torque through the engagement of the output gear of the moderator with the gear of the lower rollers. The disadvantage of the machine is that the ends of the plate materials need to have the help from other equipment for the pre-bending.