Electro motors are widely used in industry, for robots in automotive construction as well as in painting facilities. Bosch Rexroth AG manufactures electric motors in Lohr am Main and an important step in this process is glueing magnets on rotors. For this process the rotors must be preheated. Conventionally, this was done with a convection oven in batch mode, which took about an hour and lead to a bottleneck in production, especially in cold environments. Searching for a new heating process, Bosch Rexroth chose infrared heating technology, which heats much faster than hot air. After successful tests at the Heraeus application centre in Kleinostheim, Germany, Bosch Rexroth finally installed three infrared modules with controls in a heating up unit. Special shields ensure that the employees are not dazzled during operation and that the heated air can be extracted. The new system only requires about one square meter of floor space, half as much as the old convection oven. The time saving is even higher, according to the rotor size, the infrared unit needs instead of 60 minutes only two to four minutes for reaching the required temperature. “We have rotors of different diameters here. All are easily preheated by the infrared system,” says Patricia Tschorn, process development engineer at Bosch Rexroth AG, “The short reaction time of the emitters is particularly useful, which means that the environment heats up much less than with hot air before. This is pleasant for the employees!”
The infrared application center
Heraeus Noblelight has been making heat usable for industry and science for many years. The in-house application center offers the opportunity to carry out practical tests with competent technical support. The tests are evaluated and discussed with the customer. The aim is to find the best emitter type and the best configuration for the respective application - and to coordinate the heating process that fits the requirements precisely and efficiently.