Automotive Industry

The automotive industry places various demands on pad printing with parts like Isofix, fuel caps, engine covers, rims, and backlit controls. Error prevention is essential in this process.

 

The automotive industry has a wide range of requirements for pad printing. These range from simple symbols for assembly and inspection aids to armrests with white symbols on a black background, and even symbols printed in negative on transparent parts with opaque black ink. These parts are then overprinted with a translucent color to make them visible in the vehicle using LED backlighting. Furthermore, very large components, such as rims and engine covers, are also pad printed.

In addition to pad printing, error prevention and quality control are particularly important in the automotive industry. Defective parts must not be delivered under any circumstances. Increasingly, camera systems are being used to ensure quality control. Another specific feature is that pad printing machines are usually not used by car manufacturers themselves but by their suppliers.

Simple Symbols and Markings for Vehicle Components

Simple symbols or markings, such as part numbers, logos, as well as assembly and inspection aids, are applied to components like springs, catalytic converters, electronic parts, brake pads, fuel caps and rubber hoses. These products are produced either on conveyor belts or using platen systems with multiple setups:

  • Top-down printing: Our LCN Line is ideal for space-saving use above the substrate, for example, with catalytic converters. The machine can be adjusted in height, which is particularly advantageous for catalytic converters.
  • Side printing: For brake pads, where printing occurs from the side without needing to rotate the component, the MSS line is used.
  • Multi-use setups: For complex applications with different designs, colors, and selection options, the ML pad printing machine is employed.

White Symbols on a Black Background for Vehicle Interiors

In vehicle interiors, such as components like indicator levers, car keys, or vehicle safety systems (e.g., ISOFIX or Top Tether), white symbols are often printed on a black background – frequently in very high quantities.

These parts are usually printed directly at the injection molding machine to reduce costs. The robot unloading the parts simultaneously loads the pad printing machine, eliminating the need for additional conveyor systems. Since the pad printing machines are located in the robot's safety cell, no separate safety housing is required. The holders for these parts are complex, as they need to accommodate various components, potentially rotate and reposition them for optimal printing.

Backlit Controls

A particular challenge for pad printing in the automotive industry is backlit controls, such as door trim strips, center consoles with hazard lights, or climate control units.

Here, transparent parts are first printed in negative with opaque black ink and then overprinted with a translucent color. These areas are later backlit by LEDs. Backlighting places high demands on print quality, as errors are easily visible. Only our ML or Modul line with an electric pad stroke are suitable for these applications. The precise speed control of the pad ensures consistent and flawless ink transfer.

Engine Cover

Although engine covers are typically not visible in the vehicle, they still need to be printed with high quality. These parts are significantly larger than typical pad-printed components and require specialized solutions. Lines and print images that are too large for standard ink cups are implemented using transverse ink cups. For these large-scale prints, multi-color transverse ink cups are also sometimes used, which is a unique feature.

Rim

Standard machines often reach their limits when printing on car rims, as rims are much larger and heavier compared to other typical pad printing products. Covering the entire surface of the rim with the pad is often a challenge. Additionally, the different angles of the printing areas complicate the process. The movement of the rim, its rotation, and the changing angle to the pad result in numerous positioning adjustments, leading to larger tolerances and potential inaccuracies. For this application, machines specifically designed for rim printing are usually employed. Rims are either printed with a logo at a specific location or with full-surface, multi-color designs. Since rims have curved surfaces, distortion during printing must be compensated for, which requires precise adjustments and expertise from the operator.