Manufacturers have already incorporated anti-vibration technology into many larger rotary hammer models. "The larger hammers have impact energies starting around
8 ft.-lbs. going all the way up to 20 ft.-lbs.," Fernandes notes. "And at the same point, they impact anywhere from 1,000 to 3,400 times per minute. That's a lot of impacts for your body to feel."
With these tools, vibration control tends to be centered in the handles, although the technology is quickly evolving.
For example, Milwaukee Electric incorporates a series of dampeners, springs and shock absorbers in its handle design. "Our handle actually pivots as you're drilling, so that impact energy is directed down through the bit and not up into the operator's hand, wrist, elbow and shoulder," Fernandes explains. "Over the course of an 8-hour day and, more importantly, over a five-day work week, those impact energies are not subjecting the user to a lot of deteriorating energy that could hurt them over a period of time."
DEWALT's SHOCKS Active Vibration Control includes shock-mounted rubber-coated handles to reduce vibration. "Basically, the hammer has multiple springs that absorb the majority of the vibration that someone would experience if they are using a large hammer with a fixed handle," Goebel points out.
Bosch utilizes isolation of the main handle to reduce vibration on most of its models. However, it recently introduced a new concept in vibration control with its 38-lb. Jack mid-size breaker/hammer.
"Rather than add components to counter balance vibration, our engineering group looked at the hammer mechanism itself, and optimized the length of the mechanism and the length of the stroke of the piston," says Burdick. "Through that design, we were able to achieve half the vibration of other tools."
Anti-vibration technology found on the larger rotary hammers is just now starting to trickle down into smaller models. Consider the 5363 from Milwaukee Electric. "It's unique in the industry in that it's the only SDS hammer with an anti-vibration system built into it," claims Fernandes. "The 5363 has a handle with a shock absorber built into it that minimizes the vibration felt by the user, and actually makes the hammer more efficient."
Goebel foresees such vibration control becoming more prevalent in smaller rotary hammer designs in the near future. "It kind of naturally started with the larger hammers," he notes, "and it's moving its way to the smaller hammers."