Delta's Coating Machine Solution Provides High Stability and High Precision

Industrial coating technology is widely applied in industries such as paper, textiles, and leather. In recent years, metals are also used as coating materials to substrates for electrical tape and optical coating in rising high tech industries such as optical and semiconductors. As a result, manufacturers require high-quality and highly stable coating machines. Delta industrial automation integrates its products to provide a coating machine solution that can control constant tension, coating precision, and speed synchronization of coating rolls on coating machines.

Today's lithium battery coating machines used in industry cover a controlled thickness and even length coatings to film materials. After drying in dryers and finishing edge position control and tension control, coated substrates are collected in rolls on rewind air shafts. Features of the coating machine include: a coating process divided into intermittent, continuous, and transfer coating; dryers using electrically heated up and down loop blowers; digital tension controlling systems with tension closed-loop control; and coating machines driven by servo motors.

Core technologies for coating machines include keeping constant tension, retracting coating rolls, controlling high coating precision, and synchronizing the speed of coating rolls. However, if a controlling system is not precise enough it can cause constant deformation and damage to film materials, which lowers yield rates and wastes production costs.

Substrates used on coating machines demand constant tension control because they are usually very thin and easily split or wrinkle. The control system is required to quickly and precisely adjust the motors' speed because the speed of retracting coating rolls can affect the substrate roll sizes. This ensures constant tension of the surface of film materials, whether the motors are accelerating or decelerating. It is a challenge to meet the demand for high precision and customers' needs to flexibly adjust the precision in coating technology. Synchronization control on coating rolls is also required to ensure precision after moving the coating rolls in intermittent coating. Speed synchronization of coating rolls is required to compensate drive shaft speed on other workstations to prevent film materials from deforming or splitting after moving the coating rolls.

There are eight drive shaft axes moving in a coating machine at the same time. If the speed of any one of the axes is slightly different from others, especially when the motors are accelerating or decelerating, it will cause the material to deform or split. Coating machines require high performance CPUs to process an abundance of data because the machines need to control the position, speed, and movement of the eight axes, and approximately 200 digital input and output (DI/DO) points.

Delta provides industrial automation products to achieve control, motion, and drive for coating machines. The products include: high-performance mid-range programmable logic controller (PLC) AH500 Series, high performance motion control AC servo drive for network communication applications ASDA-A2 Series and general field oriented vector control drives VFD-VE Series.

The AH500 Series CPU module AHCPU510-RS2 and motion control (MC) module AH20MC-5A Series provide a controlling platform and communicate with 8 axes of AC servo drives ASD-A2-1521A-F Series through Delta high-speed motion control system DMCNET. The AH500 Series PLCs then control tension and retraction functions with AC motor drive VFD-075V43A-2 Series.

AH MC modules can control eight AC servo drives within 1 millisecond and connect all the drives with only one communication cable, which is easy and convenient for wiring. It allows users to control any axes on its network by monitoring on computers. AH CPU modules are responsible for other controls besides motion control while AH MC modules are responsible for motion controls. They are independent controllers but exchange data frequently.

The AH500 Series supports hot-swapping, which improves stability and maintainability. Its built-in software with fully integrated interface helps users to set up a hardware structure for new projects. The AC servo drive ASDA-A2 Series has numerous built-in motion control functions and a high resolution encoder to effectively improve the precision of coating machines. It also features easy wiring and is highly reliable. The AC motor drive VFD-VE Series can drive open-loop control to keep constant tension for retracting coating rolls. By changing the speed of a slave axis with speed superposition function, the VFD-VE Series can prevent tension changes on the copper when separating synchronized axes in the process of intermittent coating. It can also eliminate tension changes caused by position changes from the axes.

Lithium battery coating machines are special advanced machines both medium and large that require high precision. Delta's lithium coating machine solution is applied in actual automation production lines, and has achieved client demands for high performance, high precision, and high efficiency control.