The moving jaw body is a steel plate welding piece. The welding stress can be eliminated by heat treatment and annealing, and the defects caused by welding can be effectively eliminated by grinding the weld, so that the strength of the moving jaw body is higher. Moving jaw body is equipped with movable jaw plate front, upper with the aid of eccentric shaft and bearing hanging on the frame, lower support on the bracket, and with the bracket into a hinge, at both ends of the eccentric shaft is equipped with a belt wheel and flywheel, in order to reduce the rated power of the motor, and the speed of the machine does not fluctuate too much.