Media-resistant plain and spherical bearings in the solar cleaning robot

Problem

Good media resistance is very important for all bearing points in the cleaning robot, as they inevitably come into contact with cleaning agents. The components and bearing points must also be suitable for outdoor use and insensitive to strong sunlight and changing weather conditions. The designers were looking for suitable sockets especially for the bearing points in the wheels and in the brush.

Solution

With iglidur P plain bearings, igus offers a solution with very good media resistance. As the bearings do not require any external lubricants, neither dust nor dirt can stick to the bearing points and no maintenance is required. In the brush, the designers use igubal ESFM flange bearings. Thanks to the spherical ball, they compensate for misalignments, are corrosion-resistant, extremely wear-resistant and also completely maintenance-free.

Solar plant cleaning as a challenge for operators

Regular cleaning of solar and photovoltaic surfaces is an absolute must, but it poses a major challenge for system operators and service providers. The reason is that the surfaces are difficult to access and sensitive, and cleaning must be extremely thorough. "Manual work carried out by personnel is a common solution here, which is dangerous and physically demanding," explains Andreas Grochowiak, CEO of TG hyLIFT GmbH. The results vary from person to person, and the effort is very high for several hundred square metres of solar plant surface. The hyCLEANER black SOLAR promises easy, safe and, above all, up to five times faster cleaning than by hand, and with only low water consumption. The machine is easy to operate using radio remote control and achieves ranges of up to 100 meters without problems. Stepping onto the sensitive roof and solar panels is no longer necessary.
 

The hyCLEANER black SOLAR is used at the football stadium Stade de Suisse in Bern. There it regularly cleans more than 12,000 square metres of solar plant surface.

Lubrication-free polymer bearings for reliable support

The hyCLEANER moves forward by means of four wheels on two toothed belts. The belts are covered with special straps and exert their grip on the wet surface. For example, the hyCLEANER can move on solar panels at an angle of up to 35 degrees and can easily even cross over maintenance aisles and spaces between the panels of up to 30 centimetres. The wheels, which drive the hyCLEANER via a plastic toothed belt, are made of POM material and guided via a stainless steel shaft. "In order to prevent wear between the two materials and thus increase the service life of the cleaning machine, we decided to use iglidur P plain bearings from igus," explains Andreas Grochowiak. The material is specifically designed for outdoor use and only absorbs moisture in very small quantities. It is resilient and has a low wear rate. Another advantage: It is free of lubrication and corrosion like all igus materials, thanks to its polymer base.

The hyCLEANER moves by means of wheels on two plastic toothed belts, which are covered with special bands and generate their grip on the wet surface.

Fixed flange bearing for use in wet environments

For starting up the cleaning machine, the user only needs a water connection. A reeling device provides a simple and user-friendly hose management system over several metres. The solar surfaces are cleaned with water and a special 90 centimetre wide cleaning brush having a diameter of 30 centimetres. Upon request, other sizes can be implemented quickly and easily, thanks to the modular system of the hyCLEANER black SOLAR. The brush rotates at up to 400 revolutions per minute. This is supported by an igubal EFSM fixed flange bearing, which is easily and quickly installed on the shaft end of the brush compensating for misalignment. The spherical ball of the fixed flange bearing is made of the high-performance plastic iglidur W300, which is characterised by extremely high wear resistance and long service life.
 
Andreas Grochowiak is convinced of the quality of the igus bearings: "It's been several years since we have been relying on igus' lightweight plain bearing technology in our machines. For example, it is successfully used in our hyCLEANER blue EVO series for the cleaning of glass and other surfaces as well as in the hyCLEANER red EVO series for the cleaning of facades. “

To compensate for misalignments in the brush mounting, the designers used a square flange bearing made of lubrication-free high-performance plastic from igus.

Successfully used around the world

The TG hyLIFT GmbH sells its cleaning systems all over the world and sees the best opportunities for its products in the future. "This concept of cleaning solar plants is still largely unknown in the industry, so we have to start here and convince both solar system operators and service providers in the facility management industry of our product," explains Grochowiak. The advantages are obvious: the company saves time and resources while increasing the safety of employees. The semi-automatic cleaning machine is used, for example, at the Stade de Suisse in Bern, where the hyCLEANER regularly cleans 12,000 square metres of solar space. The solar plant cleaning system is also used in modern architecture, such as the Arnhem Centraal train station in the Netherlands and at the Marineda City shopping centre in Spain. Further projects are currently underway in Estonia and Spain. Always present: the polymer bearings from igus.

Gerald Voß (left), Technical Sales Consultant of igus, together with Andreas Grochowiak (right), CEO of TG hyLIFT GmbH.