With increasingly stringent requirements for the quality of glass bottles (including appearance cleanliness), traditional burlap sack packaging is no longer adequate for production and market needs. Our factory's current pallet packaging effectively overcomes the drawbacks of burlap sack packaging, reducing breakage of glass bottles (especially screw-top and irregularly shaped bottles) during packaging and transportation. It also avoids the problem of dust accumulation and even decaying burlap residue adhering to the bottles after prolonged storage. Because complete online glass bottle pallet packaging machines have complex mechanical structures, strict installation requirements, and significant investment costs, our factory has opted for a simple, easy-to-use, and low-cost PLC pallet wrapping machine. This machine uses LLDPE stretch film as the packaging material to stretch and wrap the glass bottles on the pallet. The packaged pallets are ideal for the storage and transportation of glass bottles and jars, greatly reducing breakage rates and improving bottle cleanliness. 1. Glass Bottle Pallet Packaging Process Requirements and System Operation First, manually fill the pallet with glass bottles from the delivery belt (the bottles can be layered according to size, specifications 1300mm×1300mm; height 800～2200mm), and use a manual hydraulic pallet trolley to pull it onto a Φ1650 steel plate turntable. Then, thread a 500mm wide, 17～35μm thick LLDPE stretch film onto the bottom of the pallet. Select "manual" or "automatic" working mode via the "human-machine interface". System operation: First, start the turntable, activate the proximity switch, and the film feeding motor rotates, allowing the film to wrap around the bottom of the pallet twice (the number of wraps can be set). Because the light is blocked by the glass bottles on the uniformly rotating pallet, the photoelectric switch fixed on the film frame and aligned with the glass bottle being wrapped is "dark-lit," so the film frame, carrying the film and photoelectric switch, rises. When the film wraps the glass bottle from the bottom of the pallet to the top, the raised photoelectric switch can receive light from outside the pallet, causing the photoelectric switch to "light up and turn off". However, to ensure a tight seal at the top edge, the film frame can be set to continue wrapping the bottle and rising for a few seconds after the photoelectric switch "lights off" (note: the film frame only moves up and down, while the tray rotates at a constant speed) before stopping, and then wrapping the film around the top of the tray twice more (the number of wraps can be set). Then the film frame descends, wrapping the glass bottle from top to bottom. Finally, wrapping the film around the bottom of the tray twice more, and then the tray stops rotating. The glass bottle tray packaging is complete. 2. System Hardware Configuration The programmable controller TSX08CD8R6AS is the pressing center of the entire system. This PLC is fully functional, reducing many intermediate contact parts, simplifying wiring, optimizing design, and improving equipment reliability. It also uses a TSX08H04M human-machine interface, allowing easy selection of five screens such as "manual operation," "automatic operation," and "parameter setting" for system debugging, parameter setting, adjustment, and selection of system operation modes. Simultaneously, external frequency converters U1, U2, and U3 are connected to control the speeds of the turntable motor, film frame lifting motor, and film feeding motor, respectively. In addition, the PLC inputs also receive switch signals such as S1 "Tray in Position", S2 "Film Carrier Lower Limit", S3 "Height Limit", S4 "Film Carrier Upper Limit", S5 "Film Initiation Start", and S6 "Emergency Stop" to ensure normal and safe system operation. 3. System Software Design According to the "Packaging Process Requirements and Working Procedures", this pallet packaging system has two operating modes: manual and automatic. In manual mode, press the dedicated buttons "A1" to "A8" on the "HMI" control panel once or several times. In case of special emergencies, press the S6 emergency stop button to stop the system immediately. Before using automatic mode, the "Bottom Ring Wrapping Count", "Top Ring Wrapping Count", "Up and Down Running Cycle Count", and the "Delay Time" for the film carriage to stop rising after the photoelectric switch receives light at the top of the pallet must be preset. Then press A8 to turn the screen to the automatic operation page. The design should also consider the following: Allow for independent adjustment of the control frequency settings of the three frequency converters (turntable motor, film rack lifting motor, and film feeding motor) to ensure proper coordination of motor speeds and optimal packaging of the glass bottles; for safe operation, the lifting limit positions of the film rack should also be considered separately; due to strong light penetration between layers of some irregularly shaped glass bottles, the direction of the photoelectric switch or the sensing distance of the photoelectric switch needs to be appropriately adjusted. Furthermore, pressing the S6 button to abruptly stop the automatic stop process is not permitted.