One of the most common uses for compression springs is in vehicle suspension. The suspension system is one of the most important mechanisms in a car and is attached to the chassis and wheels. Without spring loaded suspension passengers would be in for an extremely bumpy ride, and the car would end up breaking due to the impact between car and road surface. Due to its flexibility, a spring absorbs the shock from hitting bumps and creates a certain flexibility of movement when it compresses. Without springs, the tyres wouldn’t retain contact with an uneven road surface, causing the vehicle to bounce off the bumps.

The main components that make up a vehicle’s suspension system are coiled compression springs and shock absorbers. The springs are a coiled length of wire and are able to store energy when a force compresses them together. The same amount of energy is realised when the force ceases, and the spring then returns to its neutral length. The sprung mass is the mass of the vehicle supported on the springs, and the unsprung mass can be loosely defined as the mass between the road and the suspension springs. It is important that engineers work out the correct stiffness of spring during manufacture. Looser springs will give a light motion and smooth ride, meaning the car will glide easier over bumps and in dips; however this also means less control. Taut and heavy springs will mean the wheels don’t always keep in perfect contact with the road surface, but it does ensure better control and means that a vehicle is capable of carrying heavy loads.

Shock absorbers, also called dampers, absorb the impact of rising and falling on uneven roads. They ensure that the energy from hitting the surface is absorbed, and so it doesn’t vibrate the chassis. The shock absorbers also prevent the suspension making the car bounce, so that the wheels also stay planted on the road. The dampers are velocity sensitive, so the faster the vehicle moves the more resistance there is to bumps. Modern suspension systems are constructed so that the spring fits partly over the damper. The spring absorbs the energy from the car’s movement, and then the damper dissipates the energy by forcing oil through a tiny hole; which is a hydraulic process. This way the energy caused by the car is stopped at wheel level, and won’t cause any vibration or damage to the car’s body.

Springs are a simplistic but incredible contraption, and are used in every vehicle now made. Their presence in a suspension system ensures that travelling is smooth and the car can sustain the impacts of travelling at speed. Here at Airedale Springs we make made-to-measure compression springs for suspension systems, as well as many other springs and pressings for other industries. Our expert knowledge and experience means we can design any spring to your specifications with the highest quality materials.