Roadway condition test appts. - has extra wheel mounted on motor vehicle and braked by force opposing direction of wheel rotation

摘要

The friction value of the roadway is measured by using two wheels (13, 16) to actuate the test elements of the appts. These wheels are pressed onto the roadway by springs (15, 20). The spring used to press the test wheel (16) engages on a lever (12) which connects the wheel (13) to the vehicle. The force blocking the test wheel is generated by means of an electric motor or magnet. The armature is connected to the shaft of the test wheel via a step-down gear. The blocking force may be obtained by means of an air cylinder.