Application of PLC in the packaging control of the

PLC application in glass bottle tray packaging control

with the continuous improvement of the requirements for the quality of glass wine bottles (including the appearance, which can be safely used and the cleanliness), the traditional gunny bag packaging method can no longer meet the needs of production and market. The pallet packaging currently used in our factory can just overcome the disadvantages of gunny bag packaging, reduce the breakage of glass bottles (especially screw mouth bottles and special-shaped bottles) in packaging and transportation, and avoid the problem that the ash on the bottles after the gunny bags are placed for a long time and even be adhered to the rotten substances of gunny bags

due to the complex mechanical structure, strict installation requirements and large equipment investment of the complete set of glass bottle tray packaging machine, our factory selects the PLC tray winding machine with simple structure, convenient use and low cost, which uses LLDPE tensile film as the packaging material to stretch and wrap the glass bottles on the tray. The arrangement and deviation of the packed pallets and products are suitable for the storage and transportation of glass bottles and cans, which greatly reduces the breakage rate of bottles and improves the cleanliness of bottles

1. Glass bottle tray packaging process requirements and system working process

first fill the tray manually from the delivery belt (it can be divided into several layers according to the size of the bottle, with a specification of 1300mm × 1300mm； Height 800 ~ 2200mm), and pull it with manual hydraulic carrier Φ 1650 steel plate turntable. Then the width is 500mm and the thickness is 17 ~ 35 μ M LLDPE stretched film is threaded into the lower end of the tray. Through the "man-machine interface", select the "manual determination of viscosity of architectural coatings - stomer viscometer method GB 9269 (8)" or the "automatic" working mode

system working process: first start the turntable, turn on the proximity switch, turn the film feeding motor, and let the film wrap around the lower end of the tray for 2 turns (the number of turns can be set). Since the light is blocked by the glass bottle on the uniformly rotating tray, making the photoelectric switch fixed on the film frame and aligned with the wrapped glass bottle "dark", the film frame rises with the film and the photoelectric switch. When the film is wrapped from the lower end of the tray to the glass bottle at the upper end of the tray, the raised photoelectric switch can receive light outside the tray, causing the photoelectric switch to "light off". However, in order to make the top cover tightly wrapped, it can be set after the photoelectric switch is "on and off", let the film frame continue to rise while wrapping the bottle for a few seconds (Note: the film frame only moves up and down, and the tray always rotates at a constant speed) before it stops, and then wrap it around the top of the tray for another 2 turns (the number of turns can be set). Then, the film frame is lowered, and then the film is wrapped around the glass bottle from top to bottom. Finally, the lower end of the tray is wrapped with 2 circles of film, and the stop flow of the tray directly affects the speed stop rotation of the material testing machine. Glass bottle tray packaging is over

2. System hardware configuration

the programmable controller tsx08cd8r6as is the pressing center of the whole system. The PLC has complete functions and can reduce many intermediate and indirect contacts, which is convenient to simplify wiring, optimize design and improve the reliability of equipment operation. Tsx08h04m man-machine interface is also adopted, which can easily select five pages of images such as "manual operation", "automatic operation" and "parameter setting" to conduct system debugging, parameter setting, adjustment and select the mode of system operation respectively. At the same time, external frequency converters U1, U2 and U3 are connected to control the rotation speed of rotary table motor, film frame lifting motor and film feeding motor respectively. In addition, the input of PLC is also connected to switch signals such as S1 "tray home position", S2 "membrane frame lower limit", S3 "height limit", S4 "membrane frame upper limit", S5 "membrane feeding start" and S6 "emergency stop" respectively, so as to make the system operate normally and safely

3. System software design

according to the requirements of "packaging process requirements and working process", the tray packaging system can be used in manual mode and automatic mode. When using the manual mode, manually press the "A1" to "A8" special keys on the "human machine interface" operation panel for one or more times. In case of special emergency, press the S6 emergency stop button to make the system emergency stop. Before using the automatic mode, you must preset the "bottom coil winding times", "top coil winding times", "up and down operation cycle times" and the "delay time" for the film frame to stop rising after the photoelectric switch receives light at the top of the tray. Then press A8 to turn the screen to the automatic operation page

attention should also be paid to the design: it is allowed to adjust the control frequency setting values of the three frequency converters of the rotary table motor, the film frame lifting motor and the film feeding motor respectively, so as to make the rotation speed of the three motors match appropriately, so that the packaging effect of the glass bottle is the best; For safe operation, the lifting limit position of the membrane frame should also be considered separately; Due to the strong light input between layers of some special-shaped glass bottles, it is necessary to properly correct the direction of the photoelectric switch or adjust the sensing distance of the photoelectric switch. In addition, it is not allowed to press the S6 key to make an emergency stop during the automatic stop process