Vibration and shock isolators have been used forever in countless applications. A recent application I have been associated with highlights a double benefit that can be gained by their use. A diesel engine propulsion system on a railroad locomotive has isolators that are used to mount the engine to the locomotive frame. The engine is very dynamic and has relatively high vibration levels from the normal sources like driveshaft unbalance, piston firing and so. The isolators reduce the amount of this vibration that gets transmitted to the frame. The benefits are lower noise, reduced dynamic loads on the frame and adjacent equipment, increased crew comfort, etc.
The second benefit is for the engine itself. Locomotives experience high shock loads from coupling into rail cars and other locomotives in building up the consists and from pulling and braking. The coupler shock loads are somewhat attenuated by the coupler draft gear which is typically a laminated rubber bumper, however, some shock load still occurs at the frame and makes its way to the engine mounts. For this case the shock load is isolated from the engine by the isolators.
A generally inexpensive device serving two important functions: reducing engine loads passing into the frame and reducing the frame transmitted shock loads passing back to the engine.