Image of pageindex72008.gif

Image of noise.jpg

They say that looks can be deceiving, and when it comes to power wheelchairs, sounds can not only prove deceiving, but also disconcerting.

With power wheelchairs serving as extensions of our bodies, it's no wonder that we wish them to operate as quietly as possible. And, when they springing up with "whining," "grinding," "squeaking," and "rattling" noises, they understandably capture our attention - leading us to wonder, where's that annoying noise coming from, and how can it be fixed?

What's Normal
Make no mistake, there's no such thing as a totally silent power wheelchair. Electric motors hum, brakes click, casters chatter, and actuators buzz. Yet, on modern power wheelchairs, all of these noises are kept to a minimum. In fact, quality-concious manufacturers minimize noise by design with strict requirements like adhering to motor sound limits, using no-rattle shroud components, and placing self-lubricating bushings at pivot points - all intended to reduce noise.

Throughout the day, however, based on environment, some normal noises may seem more pronounced than others, where the click of a brake releasing and the slight hum of the motors may not be heard in a living room with a television on, but may seem ever so pronounced in a silent church. Therefore, "normal" noises can seem slightly different in varied environments, without signaling an issue.

Noticing What's Abnormal Noise
In everyday use, we learn the "normal" sounds that our power wheelchairs make, and a foremost key to proper maintenance is in recognizing "abnormal" sounds. As power wheelchairs age, they can get a bit louder in areas, and that's normal - just as a five-year-old car likely isn't as quiet as it once was. However, when a strikingly abnormal noise suddenly develops, and persists, it should be a sign that service is needed.

Noises are Sneaky
Determining exactly where an abnormal noise originates on a power wheelchair can be tricky. As mechanical machines, with pivot-point suspension, plastic shrouding, motors, and bearings, power wheelchairs can develop peculiar sounds among many components. And, pinpointing the noise can take detective work, as sound travels and bounces throughout a power wheelchair, where the location that you hear the sound seemingly emitting may not be where it originates. For these reasons, providers often must get on the floor, push, pull, and tug on a power wheelchair to attentively determine where the distracting noise originates.

Despite the tricky nature of noises, some sounds are emblematic of certain issues, and knowing the possible component that a strange sound may relate to can help toward diagnosing an issue.

The High-Pitched "Whine"
A constant high-pitch "whining" sound coming from only one motor of a power wheelchair typically relates to motor brush noise - namely caused by either an oddly-worn or damaged motor brush. Often, the brush will correct itself by "re-breaking-in" after some time. For example, if one primarily uses a power wheelchair at very low speeds indoors, and a motor develops a whine, going out for a longer stroll at speed (in a safe environment), will often resolves the issue by reshaping the brush, eliminating the whine. If the whine continues, a provider should inspect the motor.

The Gritty "Grind"
A "grinding" noise can relate to the brake, which sits atop the motor and is released as the power wheelchair drives. If dirt gets in the brake, or the brake doesn't fully disengage, it can make a grinding noise. This usually requires replacing the brake (which is a quick job on modern power wheelchairs).

Additionally, degraded caster and fork stem bearings can cause a grinding noise when maneuvering, dictating replacement.

The Squawking "Squeak"
A "squeak" or "chirp" can relate to caster bearings or suspension. If a caster bearing is squeaking or chirping, it requires replacement. If suspension makes such noises, it's a matter of pinpointing the location, and lubricating it (when suspension pivot points get wet and fill with grime, then dry out, they may squeak).

The Rumbling "Rattle-Trap"
Most modern power wheelchairs feature plastic shrouding of some kind, from fenders to battery doors, to full body shrouds. A rattling sound often points to loose or vibrating plastic. First, all plastic components should be inspected to make sure that all is secure. If all plastic is secure, but still rattles against other components, thin adhesive weather striping or a small piece of adhesive-backed Velcro loop material can be placed where the plastic rattles against another surface, working as an effective insulator.

Indeed, sounds can be distracting and disconcerting; but, with a little knowledge, detective work, and service, they can be resolved. No, a power wheelchair may never be totally silent, but it shouldn't be a whining, squeaking, chirping, rattle-trap on wheels, either!

Published 4/09, Copyright 2009,