Adjusting The Wheel Adapters - Otto Bock discovery tmax Instructions For Use Manual

Adjustments

6.12 Adjusting the Wheel Adapters

CAUTION
Incorrectly adjusted wheelbase
Risk of the user falling or tipping over
► Only adjust the wheel adapter after completing the adjustments described above.
► Maximum stability is reached in the far rear position (wheel adapter is up against the stop screw: see fig. 36,
item 2). When the wheel adapter is moved forward, the stability of the wheelchair decreases.
► Avoid extreme settings that could lead to tipping when adjusting the seat angle.
► Adjust the wheelbase so that the person pushing the wheelchair has to exert little force to tip it.
► Please note that with the rear wheel in the front position and with an unfavourable body position, the user may
tip backwards even on level ground.
► Be sure to position the rear wheels towards the rear for transfemoral amputees. This improves the stability of
the wheelchair.
► Changing the size and position of the rear wheels may cause the caster wheels to wobble at higher speeds. If
changes are required, verify the horizontal alignment of the main frame.
INFORMATION
► To change the position of the wheel adapter, the knee lever wheel lock first has to be loosened and sub­
sequently readjusted (see the chapter "Adjusting the Knee Lever Wheel Lock").
► The position of the wheel attachment bushings in the wheel adapter was matched to the chosen rear wheel
size/caster wheel size at the factory.
The wheel adapter can be shifted on the main frame. This has the following effects:
Wheel adapter/rear wheel position
Shifting to the rear (farther away from the
seating centre of gravity)
Shifting forward (closer to the seating
centre of gravity)
Setting recommendations
Depending on the clinical picture of the user, the intended area of application and the experience/strength of the
attendant, the position of the wheel adapter can be individually readjusted. The adjustments should be made as fol­
lows:
• Little force needs to be exerted when tipping up the wheelchair.
• The wheelchair will stand stable at all times on slopes/inclines.
Adjusting the wheel adapter
1) Loosen the locking mechanism linkage (see Page 15).
2) If necessary, loosen the knee lever wheel and remove the rear wheels.
3) Loosen 3 x Allen head screws on the wheel adapter on both sides (see fig. 35/see fig. 36, item 1).
4) Adjust the depth of the wheel adapter on both sides at the same time. Avoid tilting or canting.
5) Slightly tighten all Allen head screws.
6) Verify even positioning. In order to do so, measure the distance from the end of the frame tube to the back
edge of the adapter (see fig. 35, item 2). The maximum allowable deviation is 1 mm.
7) Firmly retighten all Allen head screws to a torque of 10 Nm.
8) Mount the locking mechanism linkage (see Page 15).
9) Readjust the knee lever wheel lock (see Page 23).
22 | Ottobock
Effects
Larger wheelbase; tipping resistance increases;
wheelchair is harder to tip backwards when crossing obstacles;
larger forces required for tipping
Smaller wheelbase; tipping resistance is reduced;
wheelchair is easier to tip backwards when crossing obstacles;
lower forces required for tipping
discovery tmax