Freedom Chair A08 arm rest mount

Project  / Project number: 299  /  Status:

0

The challenge

Our client is a young lady studying at university who has a conventional powered wheelchair with a channel arm rest to keep her arm in position and allow her to control the chair properly. But she was looking for a lightweight folding powered chair too, that could easily be folded and taken around in a family car.

The Freedom Chair A08 was suitable – but the arm pads were not.  Ottobock do a range of channel arm rests in four different lengths, and these can be attached to many conventional wheelchairs in place of the arm rests.  However, the arm on the Freedom Chair A08 curves, and even if it had been straight, the Ottobock arm rest on its standard mountings would have fouled the folding operation.

The solution

Initially, we attempted to make a padded platform which clamped onto the original arm rest pad. Whilst this worked to some degree, there was just too much movement in the original arm pad and its fixings so an alternative had to be found that clamped directly and very firmly onto the arm tube, with zero movement.

We took two pairs of strong industry standard polypropylene hydraulic pipe clamps – and then machined a tight fitting pair of pins to go through the original screw holes in the arm tube, and then secured these to the clamps. This prevented any tendency for the hydraulic clamps to twist around the tubing. We then fabricated a bespoke mount to attach the Ottobock arm rest to the clamps.  This allowed the arm rest to be positioned so it didn’t foul the folding of the chair.  The forward/backward adjustment of the Ottobock arm rest was retained, and we provided machined plastic shims to fine tune the height of the arm rest, and another set to fine tune the height of the joystick control.

 

Under construction in the workshop.

Detail of the hydraulic clamps and custom mounts. The standard T nuts and bars supplied with the arm rest can also be seen.

The new arm rest in position. We used the longest arm rest in the range – approx 18 inches long.

Completed and adjusted chair on the day of delivery.

The benefit

Our client has greater freedom to travel.

Leave a Reply

Your email address will not be published. Required fields are marked *