The machine body is welded of quality and treated by tension elimination, improve stability and reliability of precision of the machine. In order to guarantee the machine running in stable and smooth, adopts the design of symmetrical two slid boards with balance. The precision of mold adjusting up to o 1 mm, safety, reliable and convenient. Crank, gear, connect bar are oxidized hardening and milled, having super comprehensive mechanical performance and durable function. Reasonable structural design, is convenient for automatic production and line production. Used reliable high intensity clutch/brake and twin electromagnetic valve, overloading protector can guarantee safe production all-around.