Annual Report 2010 - Knorr-Bremse AG.

RepoR t
99
Products
Reliable, safe, high performing, efficient and tailored to the requirements of international
customers – these were the characteristics of the commercial vehicle products either newly
developed or further improved during 2010. They included the AEBS automatic emergency
braking system, the compressor with clutch and the latest version of the TEBS trailer electronic
braking system.
Screw compressor for hybrid buses
In response to growing demand for commercial vehicles that use hybrid drive technology, Knorr-
Bremse began series production of screw compressors for hybrid buses in spring 2010. The new design
of compressor is to be installed in the 5,000 Volvo buses ordered as part of London’s fleet renewal
program, some of which is due to be completed in time for the 2012 Olympic Games. In addition to
supplying Volvo, Knorr-Bremse has also launched similar projects with other commercial vehicle manufacturers.
Screw compressors are capable of producing large volumes of compressed air, using two synchronous
counter-rotating screws with a large inlet valve and smaller outlet valve. Unlike conventional compressors,
they are not powered by the vehicle engine but by their own electric motor. They are low-vibration
and quiet in operation.
Knorr-Bremse is convinced of the potential offered by screw compressors and has also started designing
a compressor application for hybrid trucks. Unlike buses, trucks are not constantly stopping and
starting and therefore require less air to operate their brakes, so the engineers are focusing on designing
a unit that produces smaller volumes of compressed air.