This paper presents air brakes noise study to decrease the complaint noise occurrences greater than 50 dB. Local market specific brake noise test procedure is developed to get objective and subjective noise measurement from heavy commercial vehicle. The test route is determined to profile the different brake lining temperatures to cover low, moderate and high braking applications at forward driving, reverse driving and left-right cornering conditions to simulate existing different braking conditions. The vehicle level objective and subjective brake noise data is evaluated to quantify brake noise perception from driver point of view. It was seen that the front right wheel noise level "5,25% noise occurrence over 50 dB" can be an issue and cause customer dissatisfaction. The wheel brake components that a maximum noise occurrence is recorded were delivered to test center to replicate noise profile on the dynamometer test rig. The dynamometer noise spectra shows major noise at the frequency, 4400Hz like as vehicle noise search data. Pad size and chamfer can change modal coupling contact area in addition to adjust contact pressure distribution between rotor and pad. Thus, air disc brake pads with different chamfer and slot combinations are tested to reduce number of noise occurrences ending up with acceptable customer level.

Tutuk, Ergün; Akca, Dilek; - Ford Otosan Speier, Torstein; - Link Engineering Güntay, Bora; - Ege Fren