Due to drivers‘ increased quality consciousness, brake noises are accepted
less and less. What causes these, at times unpleasant noises and how
can they be counteracted? When braking, vibrations always occur due to
dry friction, which, depending on the frequency, are described with a wide
variety of terms.
In the low frequency range, they are referred to as, e.g., rubbing, buzzing
or juddering and in the medium and high frequency range, e.g., as squealing
or wire brush.
In order to counteract these phenomena, TMD, Europe‘s leading brake pad
manufacturer, has been carrying out intensive basic research for many years.
At a very early phase of new vehicle development, the results contribute
towards comfort optimisation.
Consequently, their intrinsic vibration behaviour and noise absorption properties
are thoroughly tested when developing new brake pad materials. With
the results achieved, the noise behaviour of new vehicles and their components
are analysed and infl uenced on special noise test benches, in some
cases, with complete prototype axle components and brakes. During this
early development phase, changes can still be made to the wheel brake and
pad contour.
At a later point in time, practice-oriented vehicles tests are then performed
during which the intensity and frequency of any noises are determined. The
test includes endurance runs in Spain, as well as assessment during a variety
of street circuits and high-speed judder tests. In this context, it is of particular
importance to determine which component vibrates at what frequency in
order to be able to take targeted noise absorption measures. Fine adjustment
can now be performed by small contour modifi cations such as grooves and/or
chamfers. The compressibility of the brake pads can also be changed within
the framework of the tolerance ranges.
Depending on the application, the wedge-shaped underlayer patented by TMD
also contributes towards optimisation. In the ideal case, so-called secondary
measures such as rubber varnish, adhesive foils, damping plates, counterweights,
etc., can be dispensed with. Although these ancillary materials can contribute
towards improvement, they also have an effect on the pedal feel, the wear volume
and, naturally, the costs.
Consequently, in the case of a brake pad, a compromise must always be found
between safety, comfort and economic efficiency.
In this context, the correct allocation of the different brake pad materials is just as
important as the assessment of the overall condition of the complete wheel brake
and the other axle and wheel suspension components.
One must also be aware that each change to the vehicle such as wide tyres,
changes to the track, lowering, etc., also considerably affects the noise and
comfort behaviour of motor vehicles.
less and less. What causes these, at times unpleasant noises and how
can they be counteracted? When braking, vibrations always occur due to
dry friction, which, depending on the frequency, are described with a wide
variety of terms.
In the low frequency range, they are referred to as, e.g., rubbing, buzzing
or juddering and in the medium and high frequency range, e.g., as squealing
or wire brush.
In order to counteract these phenomena, TMD, Europe‘s leading brake pad
manufacturer, has been carrying out intensive basic research for many years.
At a very early phase of new vehicle development, the results contribute
towards comfort optimisation.
Consequently, their intrinsic vibration behaviour and noise absorption properties
are thoroughly tested when developing new brake pad materials. With
the results achieved, the noise behaviour of new vehicles and their components
are analysed and infl uenced on special noise test benches, in some
cases, with complete prototype axle components and brakes. During this
early development phase, changes can still be made to the wheel brake and
pad contour.
At a later point in time, practice-oriented vehicles tests are then performed
during which the intensity and frequency of any noises are determined. The
test includes endurance runs in Spain, as well as assessment during a variety
of street circuits and high-speed judder tests. In this context, it is of particular
importance to determine which component vibrates at what frequency in
order to be able to take targeted noise absorption measures. Fine adjustment
can now be performed by small contour modifi cations such as grooves and/or
chamfers. The compressibility of the brake pads can also be changed within
the framework of the tolerance ranges.
Depending on the application, the wedge-shaped underlayer patented by TMD
also contributes towards optimisation. In the ideal case, so-called secondary
measures such as rubber varnish, adhesive foils, damping plates, counterweights,
etc., can be dispensed with. Although these ancillary materials can contribute
towards improvement, they also have an effect on the pedal feel, the wear volume
and, naturally, the costs.
Consequently, in the case of a brake pad, a compromise must always be found
between safety, comfort and economic efficiency.
In this context, the correct allocation of the different brake pad materials is just as
important as the assessment of the overall condition of the complete wheel brake
and the other axle and wheel suspension components.
One must also be aware that each change to the vehicle such as wide tyres,
changes to the track, lowering, etc., also considerably affects the noise and
comfort behaviour of motor vehicles.
