Evolution Of The Electric Wheelchairs

The first electric wheelchairs were introduced in America in the 1950s. Whereas today's electric wheelchairs could rightly be called "electronic," the first wheelchairs were truly merely electric. The E& J 840 was a simple machine that had no circuit boards and no smooth, proportional control like today's electric wheelchairs. Instead, the joystick was pushed or pulled against 4 on/off switches which would cause the chair to jerk when it started, stopped or changed directions. Some of the jerkiness was mitigated by the two very heavy series wound or field coil motors which would start up slowly. This was extremely inefficient, not to say downright excruciatingly slow. The chair had two basic speeds, high and low. The chair had two six-volt batteries which were connected in parallel for low speed and in series for high speed. You would have to be stopped to switch between the two speeds.

The next big step in motorised wheelchair development was the introduction of electronic circuitry and proportional control drive. This allowed the wheelchair rider to have greater control over the operation of the chair. Now, the further the wheelchair rider moved the joystick in the direction she wanted to travel, the faster the chair would go in that direction. Electronic circuitry also allowed for the replacement of the series wound motors with much more efficient and lighter permanent magnet motors. Now, instead of being limited to starting off at a crawl, the wheelchair rider could start off at any speed the chair was capable of.

The first of these proportional drive wheelchairs was the Motorette, which was an add-on unit to a manual wheelchair. The two 12-volt motors sat on top of the rear wheels just behind the rider. The motor shafts turned a small cog which pressed against the rear tire. The cogs would slip when the tires got wet or if they weren't fully inflated. Although the batteries were placed forward under the wheelchair, the weight of the motors made the chair tippy. When the Motorette malfunctioned, "it went crazy and acted like a bucking bronco," said one person familiar with the chair at the time. Still, the Motorette, when it was working right, made for a faster and smoother ride.

Most of the early electric wheelchairs used a slightly modified manual wheelchair frame with wheelchair batteries, belt-drive motors and a control box added on. The rear axle mounts were placed further back on the frame, pushing the center of gravity of the chair forward to compensate for the added weight of the batteries in the back. Little else was done to the frame. Wheelchair manufacturers, at this time principally Everest and Jennings, hadn't figured that the chairs would be used by active persons outside the home or institution. This led to serious problems when an electric wheelchair rider would drive his chair into a curb at the lightening speed of 3 miles per hour, bending the caster forks and cracking the frame.

From what it was, to become what it is today Invacare electric wheelchair, Pride mobility wheelchairs, Guardian wheelchair, Jazzy electric wheelchair, and Merits wheelchair has definitely created much more efficient electric wheelchairs to cater to the higher demands of the modern world. What's more they have made it even more affordable compared to the yester-years, even used electric wheelchairs are of comparable price to brand new manual wheelchairs.

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