Pad printing color registration problem
Any printing method will involve multi-color problems, and pad printing is no exception. However, the shapes of products involved in pad printing are very different. Therefore, the problem of color registration in pad printing is more complicated.
Generally speaking, as many sets of ink supply systems and print heads as there are pad printers, there will be as many color registrations. Each ink supply system can use inks of different colors, or inks of the same color.
1) Multicolor pad printing on one side
Products, especially injection molding products with three-dimensional shapes, often have many surfaces, requiring multi-color pad printing on the same position on one surface. This is the simplest type of color registration for pad printing, whether it is a shuttle pad printing machine or a turntable. Type pad printers are competent. After finishing one color pad printing, the product moves to another position for pad printing of the second color until all colors are completed. The positional movement of the shuttle pad printing machine and the turntable pad printing machine is basically equidistant and controlled by cylinders. Multi-color pad printing using such a pad printer requires the multi-color patterns to be approximately at the same position on the product.
Nowadays, although many products are multi-color pad printing on one surface, there is often a large distance between the multi-colors, such as the panels of some household appliances, or some long-shaped products. At this time, only the shuttle pad printing machine may be used. It can be completed with the addition of a servo workbench. The servo-controlled workbench can easily control the moving distance between each station and the next station.
2) Multi-color pad printing on different sides
Now more and more three-dimensional products require multi-color pad printing on multiple sides. Initially, a single-color pad printing machine was used to pad print one color by one color, but this method is slow and costly, and each position needs to be printed with a separate jig.
With the widespread use of servo systems on pad printers, such products can be easily completed with a shuttle pad printer plus a set of servo-rotating fixtures
Hair dryers, safety helmets, electric toys, cameras and other products with complex shapes often require printing of scales, characters, and patterns on all sides, which can also be the same color or different colors. For products such as pad printing, it is necessary to analyze the side of the product that needs to be pad printed, the positional relationship of the printed graphics on each side, and then set the parameters of the servo motor.
It should be said that even a pad printing machine with a servo device is very slow, but its outstanding advantage is that it can be completed with a set of fixtures on one machine, and one machine can be operated by only one person. Save labor cost.
Obviously, the pad printing machine of the servo device adopts the human-machine interface and PLC system, which has high requirements for the operator's technical level. The operator must not only understand the structure and performance of the machine, but also understand the printing process.
