Up and away

Fully automated tempering of car headlights

When the material is free of stresses, the product keeps its shape. A proven method for the internal harmonization of materials is tempering. Modern thermal systems such as those produced by CeraCon GmbH do this by conveying components through heat tunnels on multiple levels to save space. In a new system, safety and axis systems from Festo are used to optimize the stress relief process for car headlights during tempering.

Light only achieves the desired effect when it is controlled. Car headlights are a perfect example of this. Two small 12-volt light sources can light up a defined section of road thanks to modern optics. When producing car headlights, particular attention has to be paid to ensure that they are perfectly shaped. Material stresses caused by joining together multiple plastic parts are relieved by heating the products over a long period of time. CeraCon GmbH specializes in systems for this so-called tempering process. Founded in 2000, the company has a product range that includes thermal systems for relieving stresses in a wide range of materials and components. In the latest machine from CeraCon for tempering car headlights, Festo components literally play a supporting role in the form of ready-to-install complete solutions. The highlight of this solution is a five meter high vertical lift. Equipped with the new CMGA safety system, it guarantees not only the rapid transport of products, but also protects the machine and its operators.

Heating tunnel on four levels
In CeraCon's new thermal system, car headlights spend an hour "destressing" in a warm bath in an environment where the air temperature is kept at a constant 266° F (130°C). To keep the footprint of the inline system as small as possible, CeraCon has developed a customer-specific, multi-level horizontal system based on its own proven components. Component carriers pass through a heating tunnel measuring around 12 meters in length on each of the four vertically stacked sections. The individual transport levels are connected using lift systems which are responsible for the vertical lifting at the entry and exit points. The footprint of the multi-level system is just a quarter of the size of a horizontally built oven. 120 components pass through the thermal system every hour with a cycle time of 30 seconds.

Fully in the frame

When it comes to tempering car headlights in the new system, uniform heat distribution is of paramount importance. This depends not only on a sophisticated ventilation and heating system, but also on the smooth transport of component carriers. To guarantee these conditions, CeraCon uses type EGC toothed belt axes. They offer high speed and dynamic response. Specially developed profiles with an optimized cross section make the actuators torsion-resistant with a high load bearing capacity. The EGC variant used in this system, which extends to an impressive height of around four meters, transports the component carriers from one level to the next in the lift system. CeraCon and Festo had to come up with something very special, in order to create the complete system, with the CMXR controller and CMMP-AS and CMMS-AS motor controllers. CeraCon began by making the frame for subsequent installation in the system, which would also be used for the secure transport of the very long axis. Once delivered to Festo, it was equipped with the EGC toothed belt axis and all the wiring and tubing was fitted. Back at CeraCon, the turnkey system just had to be set up and adapted to the rest of the installation.

Safety in the lift system

The toothed belt axes of the new thermal system are actuated using the CMXR multi-axis controller. The complete kinematic system solution combines a mechanical system with electric actuator and control technology into a complete motion control package, with integrated interfaces to all system components. Special features such as smooth position transitions considerably reduce travel times. Speed must not come at the expense of safety, however. This is ensured by the new Festo CMGA safety system, which guarantees the safe operating stop of the lift system. Employees can access the lift shaft without risk when carrying out maintenance work. CeraCon collaborated with experts from Festo to develop a new redundant brake system for the installation. The employees of both companies worked very closely together during all phases, from the joint risk assessment to technical implementation of the fully automatic and manually executable brake test.

Engineering know-how makes the difference

Intensive co-operation is also the reason why CeraCon CTO Erich Krämer has been choosing Festo for many years: "Punctuality, reliability and competency are crucial factors in plant engineering. I have been working with Festo in a number of different areas of the industry over the last 25 years or so and I greatly value the engineering expertise of Festo employees." Both companies joined forces and worked together from the design stage to the commissioning phase. Together they developed a technologically advanced solution, which sets a new benchmark in the area of thermal systems. The new system provides Tier 1 suppliers with a high-performance inline solution for tempering car headlights that saves space and that guarantees the highest possible level of employee safety.

CeraCon GmbH

Talstrasse 2
97990 Weikersheim


Key activities: Design and manufacture of customer-specific systems for the thermal treatment and buffering of components and for the processing and application of foam seals