The Development Of The Tear Tape Feeding Control System On The Cigarette Packing Machine

The tear tape which is also called the golden lug strap can be found on the surfaces of cigarette packs, recording cassette boxes and other products which are covered with pellicle. The purpose of putting the tear tape on the pellicle of the products is to help consumers to open the products more easily and to make the products look more beautiful and even to prevent adulterators from making similar false products. Packing tear tape is an important step on the automatic cigarette production lines in the cigarette factories. The feed of the tear tape must keep in synchronism with the run of the cigarette packing machine at every moment. If the speed of the cigarette packing machine changes, the speed of the feed of the tear tape will also change to make the tear tape stand the uniform pull and to ensure the packing quality of the cigarettes. Whether this step is normal or not has direct effects on whether the whole packing process runs well. It also has effects on the production efficiency and the packing quality of the products. The old feeding mechanism of the tear tape on the cigarette packing machine has some defects that cannot be avoided. Sometimes the defects can greatly influence the normal packing process. This thesis introduces the development of the tear tape feeding control system on the cigarette packing machine. The structures and features of the original tear tape feeding mechanism of the cigarette packing machine and its defects are analysed. A tear tape feeding control system with electric transmission is designed and accomplished. The problems which appear during the feeding of the tear tape on the cigarette packing machine are solved successfully. The permanent magnetic servo DC motor is used as the driving source of making the axis of the tear tape rotate to feed the packing mechanism with the tear tape. The Pulse Width Modulation (PWM) technology is used to design the high efficiency driving circuitry in the control system. The 80C31 Single-chip Microprocessor is used as the core processor The close loop control technology, linear sensor, signal isolate converter and signal processor unit are applied to control the permanent magnetic servo DC motor to control the rotating speedof the axis of the tear tape. So the tear tape is ensured to be fed steadily according to the demands of the packing machine at any time.