Five kilos lighter: lighting installation optimised with plastic bearings

The gyroscopes have a span of over two metres and are used at concerts on indoor stages as well as on outdoor festival stages. The movements and light colours are controlled from the lighting technician's console.

The rotating circular elements are equipped with motor and gear pairs. A suitable bearing solution was sought for the drive shaft at the output of the motor housings.

During the demonstrations, the gyroscopes are exposed to temperatures of almost 50°C and during transport from the venue to the storage area from -10 to 45°C. The bearings must be able to withstand considerable vibrations and shocks caused by repeated assembly, dismantling and transport.

Due to their outdoor use, they must also be corrosion-free , free of dust and grease and work absolutely reliably even if they are in use for several months on tour without maintenance.

And there are further requirements: the bearings must not be magnetic so as not to cause electromagnetic interference, and they must be as compact and light as possible to keep the weight of the rotating elements low and minimise the size of the motor and gearbox components.

As perfect alignment of the shaft is not possible, the developers focussed their search on self-aligning bearings with ball and socket joints.

Kellook turned to igus and found the perfect solution with igubal EFSM four hole flange bearings in combination with sleeve bearings made of iglidur J material, which serve as spacers on the drive shaft.

As with all igus bearing products, integrated solid lubricants in the plastic material ensure low-friction dry operation without the need for external lubricants. In this way, €19.72 can be saved on lubricant every year in this application. More decisive than the material savings are the labour savings: the use of igus bearing eliminates around 32 hours of labour for preventive maintenance each year.

And there is a further plus point: Kellook was able to weight saving of 5kg in the rotors, which was of decisive importance for the project, as this allowed the size of the motor and gearbox pairs to be reduced and the motor housings to be successfully integrated into the thickness of the rotors. This streamlining not only facilitates transport and assembly, but also represents a considerable aesthetic gain.