When vehicles were first developed, the bumpers on them were usually just solid metal bars attached to the frame. When a vehicle had a low-speed front or rear-end accident, these types of bumpers transferred the energy of the crash right onto the vehicle. The energy transference typically caused a fair amount of damage to the front and/or back-end of the vehicle that was expensive to repair. The energy from the impact also transferred into the car which often resulted in injuries to the driver and passengers. A lot has changed since those early days and now the bumpers are made of energy-absorbing materials that reduce the amount of damage to vehicles and passengers.
How Energy Bumpers are Made
In 1971, the U.S. National Highway Traffic Association demanded that cars bumpers be able to absorb a slow-speed impact of up to 5 miles per hour. The first energy-absorbing bumpers were typically made by placing pistons between the front of the frame and the back of the bumper. Today, the bumpers are made out of plastic and cars use crumple zones to absorb the impact of a low-speed accident. The crumple zones are made by placing foam between the bumper and frame and by attaching the bumper to the fenders instead of the frame.
Another change in regulation made it so car bumpers are placed at the same height range on vehicles so a bumper will hit another bumper. In the case of trucks, a low bar is now placed on the back of the trucks to absorb an in impact. These bars move a little bit when hit and this movement will reduce the amount of energy getting transferred to both vehicles.
How the Bumpers Work
When a car hits something at a low speed, the bumper will press backward to use the crumple zone to soften the impact as the foam and fenders absorb the energy. The crumpling of the bumper, fender, and foam limits the amount of damage that can happen to the car and the people inside of it.
At Romeo Rim, we are a leading supplier of the Energy Absorbing (EA) Bumper Module System for the transit, para-transit and delivery truck markets, contact us today for more information or even info on molding solutions.