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ENGLISH
Nitrum / Nitrum Hybrid Rev.C
Castors
Castor, Castor adapter, Castor fork
From time to time the wheelchair may veer slightly to the right or
left or the castors may flutter. This may be caused by the
following:
• Forward and/or reverse wheel motion has not been set
properly.
• The castor angle has not been adjusted properly.
• Castor and/or rear wheel air pressure is incorrect; wheels do
not turn smoothly.
The optimum adjustment of the castors is required so that the
wheelchair runs in a straight line.
The castor plates must be re-adjusted, and the wheel locks must
be checked every time the rear wheel position has been altered.
Adjusting the castor
Setting directional stability and fine-tune caster-height
These are works-settings and require special tools- please
contact your dealer for support.
Adjusting the caster-fork angle
This adjustment is necessary when changing the front- or rear
seat-height.
CAUTION:
Failure to adjust the correct angle can result in caster-flutter,
locking caster wheels and injury of the user.
Loosen Allen screws (A) (Fig. 4.15.1). The caster-fork angle can
now be adjusted to the correct position: the flat section of the
fork must be positioned 90° to the ground (Fig. 4.15.2). Once
you have set the correct position, then tighten the allen screws
(A) using the following procedure:
Tighten the outer allen screw first to a torque of 7Nm, than tight
-
en the inner allen screw to a torque of 7Nm.
Repeat this procedure up to 6 times until both allen screws are
evenly tightened to a torque of 7Nm.
Fig. 4.15.1
Fig. 4.15.2
A
90°
Anti-Flutter adjustment
Most caster-forks are equipped with an anti-flutter adjustment to
suppress caster-flutter
Turning the set-screw (Fig. 4.16 - A) on the caster-fork
clockwise using an allen-key, will put load on the bearing and
reduce caster-flutter.
You might notice that the caster-fork does not spin freely but
with a slight resistance. This has no effect on the driving
behaviour of the wheelchair.
CAUTION:
When load on the bearing is released by turning the set-screw
counter-clockwise , caster-wheels can be prone to flutter on
medium or higher speeds. If you choose to conduct this
adjustment, make yourself familiar with the driving-behaviour of
the wheelchair.
DANGER:
Caster-flutter can cause a sudden lock of the caster-wheels on
medium or higher speed, which can cause the user to fall out of
the wheelchair.
Fig. 4.16
A
