Release time : 2015-06-12 11:37:29
The ball roller bearing, developed by Schaeffler Group Industrial, represents a totally new rolling bearing series. This innovation is based on a novel rolling element in combination with new assembly methods. All areas of the conventional rolling element ???ball??? that are not under load are removed. This means that 15 percent of the ball diameter is cut off on both sides of the ball. The result is the so-called ball roller, a ball that is flattened on both sides, being 30 percent narrower than a true ball. This saves valuable space. Moreover, the particularly ???slim??? shape of the ball roller, as well as specially developed assembly methods, allow an increase in the number of rolling elements so that a filling capacity of up to approx. 90 percent can be achieved. More rolling elements in the same space result in clearly higher load ratings and correspondingly longer service life. This also opens up new downsizing opportunities for products and assemblies.
One example: A standard 6207 ball bearing according to DIN 625 incorporates nine rolling elements which is equivalent to a filling degree of approx. 60 percent. In comparison, a ball roller bearing of the BXRE207 design contains 14 rolling elements in the same space. Here the filling capacity amounts to approx. 90 percent; the bearing life increases by 2.4 times. The ball roller bearing offers new technical opportunities, whether in terms of energy efficiency, downsizing options or enhanced performance.
The ball roller bearing was presented for the first time as a project study at the Hanover Fair 2007. Since then, it has been further developed in four dimensions and to series maturity by the Schaeffler engineers. Customer requirements took center stage throughout the entire development process.
Series BXRE: Downsizing or enhanced performance
The single row BXRE bearing offers higher load carrying capacity than a standard ball bearing in the same space. This is thanks to an approx. 50 percent increase in rolling elements, which are fitted using an innovative assembly method. Due to the resulting filling capacity of approx. 90 percent, the BXRE bearing is capable of withstanding even extreme loads. BXRE bearings are therefore particularly suitable when it comes to the downsizing of products and assemblies, since they require less radial space with the same shaft diameter and the same load ratings. Typical application examples are electric motors, washing machines, chainsaws and industrial gearboxes.
Series BXRO: Competition for bearings with one or two inner rings
Ball roller bearings of the BXRO series are double row bearings whose rows of rolling elements are in an O arrangement. Therefore the bearings can support both radial and axial forces. In comparison to series 32 ball bearings, up to 50 % more rolling elements can be fitted in these ball roller bearings due to the innovative assembly method, which enables higher basic load ratings in the same space. The advantages of the BXRO over the 33 series with two inner rings lie in the simplified fixation of the inner ring on the shaft. The optimized raceway geometry of the single-piece inner ring results in increased bearing accuracy. Fields of application include automotive manual transmissions or textile machinery.
Series BXRT: Low-friction alternative to tapered roller bearings
The tandem design of the ball roller bearing is a double row bearing whose rows of ball roller are in a tandem arrangement. The rolling elements can be guided using one or two cages. The two-cage design enables the optimal adjustment of the two raceways independently of each other to perfectly match the application. This ensures maximum load support with minimum size and lower friction. Compared to tapered roller bearings, friction is about 30 percent lower thanks to the elimination of rib friction. This means that the energy consumption can be significantly reduced. Application opportunities are differentials and manual transmissions, hydraulic motors and pumps.
Special series for wheel bearings with reduced weight and friction
A special ball roller bearing series has been designed for use as wheel bearings with reduced friction and weight in passenger cars and commercial vehicles. The four-row BXR4 wheel bearings offer higher load carrying capacity and therefore enable more compact designs than conventional wheel bearings from volume production. It is particularly attractive for use in driven axles. Less friction and the lower mass of the bearing and wheel carrier make a significant contribution to reducing the fuel consumption and exhaust emissions.