The Controlling System’s Design Of Laser Die-cutting Equipment

With the development of our society, the traditional die-cutting technology in packagingindustry is becoming more and more difficult to meet the demand of small amount and varietiesof die-cutting sample box because of its complex process flow, fixed form and expensivedie-cutting plate manufacturing cost. In view of the current situation, this paper proposes a newkind of laser die-cutting technology which is convenient and has high precision, simple processand very high efficiency. It is suitable to the pipeline work.The laser die-cutting system is a high technology which concentrates the laser, optics,precision machinery, control, software and electrics. The operating principle is as follows. Thereading, computing, parameter configuration, die-cutting data generating and storing of the PLTvector file are controlled by the upper computer. After the die-cutting begins, the data is sent tothe upper computer for storage by the USB. The lower computer breaks off for5μs and gets outthe die-cutting data for doing the corresponding compensation calculation. Then, the controllingsignal of the galvanometer scanning and the power signal of the laser are generated forcontrolling the orbit of the die-cutting spot and the magnitude of the laser power. This papermainly aims at the investigation of the control system of the whole device and its emphases is tocomplete the control of the galvanometer scanning system, laser power and transmitting devisesrespectively and synchronously.In order to improve the performance of the whole system, the parallel arithmetic scheme ofthe upper computer and lower computer is applied in this paper. For the design of the hardware,Cyclone П set FPGA chip EP2C20is chosen as the main control chip and the USB is applied tocommunicate in the communication module. The16high precision DA conversion chipDAC7741is applied to control the galvanometer by converting the digital signal to analog signal.The control of the laser power is completed by the generation of the PWM wave form throughthe FPGA and the generation of the analog signal through the control of the12serial DAconversion chip DAC7611. For the control of the flight instruments, this paper applies thestandard485chip to accomplish the control of the upper computer and frequency transformer.And the closed-loop control is completed by the feedback of the velocity of the conveyer belt and die-cutting beginning signal through the coder and photoelectric switch.For completing the synchronous control to these three sides, this paper firstly proposes thesynchronous control of the power and the kinematic velocity by the study of the vector file andthe combination of distortion compensation scheme with the orbit algorithm. Then, thecoordination control scheme of the transmission devises, galvanometer scanning and laser poweris proposed under the situation that the velocity of the conveyer belt is fixed basically.