Windscreen wiper system in particular for a motor vehicle

The windscreen wiper mechanism, for a motor vehicle, has a wiper bearing (14) with a shaped tube body (18) to take the wiper shaft (28) which carries the wiper to and fro across the windscreen. The shaped tube has nominal fracture points (50) as grooves to take up any abnormal forces (F) e.g. a pedestrian striking the windscreen. A ring-shaped disk (54) acts as a trip, inserted into a wedge-shaped groove (52) in the wiper shaft.