by Joanna Dykhuis, IQS Editor
When Rafael Nadal won the French Open in early June, he reclaimed his spot as the number one men’s singles player in the world. Like many other professional tennis players, Nadal played with a small rubber vibration absorber on his strings to minimize vibrations when the racket and ball made contact. Some believe these accessories lessen the risk of developing tennis elbow while others count on them as their good luck charm. In reality, the only difference is the perceived reduction of string vibration and sound. Vibration absorbers are used far beyond tennis courts, however, and they play an important role in protecting machinery and equipment from noisy and damaging vibrations.
Rubber is durable and dense which makes it an ideal material for absorbing the energy of an impact. When a tennis ball hits a racket, vibrations travel along the strings into the frame and then into the player’s hand, wrist and arm. The rubber of the vibration absorbers takes in the energy so only a small amount of it passes on to the player. The variety of shapes and sizes is endless because rubber lends itself well to processing. Vibration absorbers, also called vibration isolators or dampeners, may be long and narrow or round and thick. For tennis rackets, the more strings the absorber comes into contact with, the more vibration it can absorb.
Photos courtesy of Bushings, Inc.
Rubber is also a key component in industrial vibration absorption and the most common device is a rubber mount that is placed between two pieces of machinery or parts to minimize contact and the transfer of vibrations. These shock-reducing devices absorb energy from jarring movements and vibrations, two unwanted side effects of many equipment processes. These useful devices vary widely and range from simple rubber bumpers to spring-loaded shock absorbers. Rubber bumpers and other similar products are used in a large number of machines in virtually all industries. They are also found in every form of transportation vehicle to protect certain parts of the engine or chassis from hitting and damaging other parts. Vibration isolators absorb impact from normal use as well as from rough conditions. Rubber pads have a similar purpose and are typically placed between a machine and the floor to dampen noise, absorb vibrations and minimize wear and tear. Many washers and dryers in both residential and commercial settings are set on these pads because of the vigorous motion of the drum during the spin cycle. Vibration absorbers are also used with structures such as bridges or sports stadiums as a protective measure against vibrations that come from traffic, wind, people or earthquakes.
Another category of vibration absorbers is also widely used but is slightly more complex than a basic piece of rubber. Mechanical vibration absorbers are most often referred to as shock absorbers or shock mounts and provide a cushion when under impact. Spring-loaded shock absorbers, hydraulic vibrations absorbers and bushings use compression and decompression to contain movement instead of the material absorbing the impact. Because there are moving parts, shock absorbers may require attention and repair after heavy usage to ensure their efficiency. Generally, however, they still fulfill their role of protecting moving parts from each other to reduce contact and therefore equipment malfunction and decreased production. Whether helping a tennis champ achieve another victory, keeping your washing machine from shaking the whole house or preventing machinery collisions, vibration absorbers have an impact.