Electronic devices, instruments and systems installed on vehicles for both road and rail transport are subject to stresses transmitted by the unevenness of the ground or the rail joints. If these stresses, in the form of vibrations or repeated shocks, are not sufficiently reduced by the vehicle’s main shock absorbing systems, they can have an effect on its running and on the duration of some of the systems installed on board. In other cases, the source of vibration is installed in the vehicle (the vehicle’s engine is an obvious example) and so any devices placed near it need to be protected. In all cases, devices installed in transport vehicles may be affected by accelerations in various directions, at times significant, either during normal use or in the case of exceptional events (accidents). For this reason, all the anti-vibration mounts installed must be of a sufficient size not only to optimise the reduction of vibration or impact stress, but also to resist inertia loads due specifically to these accelerations.
The 500 series ear shock absorber have been adopted most for Heating, ventilation and air conditioning systems in railway, subway and buses.