Corghi A 222 Manual De Uso página 114

Tube type tyres. As a tyre has to contain pressurised
air for a fairly long time, an air chamber is used. The
valve for adding air and maintaining, controlling
and restoring air pressure is part of the chamber
in this case.
Tubeless tyres. Tubeless tyres consist of a tyre with
inner sidewall lined with a thin layer of special
impermeable rubber, called liner. This liner helps
to maintain air pressure in the casing. This kind of
tyre must be mounted on a specific rim, to which
the valve is directly fixed.
II - Rim (Wheel). The wheel is the rigid metal part
which connects the vehicle hub to the tyre, on a
fixed but non-permanent basis.
Rim profile. The rim profile is the form of the sec-
tion in contact with the tyre. It comprises different
geometric forms, which ensure: easy tyre mounting
(bead insertion in the rim well); safe driving, in terms
of the bead anchored in its seat.
The rim section shows its various parts: a) rim width
– b) shoulder height – c) tubeless anchoring (HUMP)
– d) valve hole – e) ventilation opening – f) off set –
g) central hole diameter – h) attachment hole centre
to centre i) keying diameter – j) rim well.
III - Air chamber (tube type tyres). The air chamber is
a closed ring-like rubber structure with valve, which
contains pressurised air.
Valve. The valve is a mechanical device to inflate/
deflate the tyre and maintain air pressure inside the
air chamber (or tyre in the case of tubeless tyres).
It consists of three parts: the valve closing cap (a)
(to protect the internal mechanism from dust and
guarantee air tightness), an internal mechanism (b)
and the base (c) (the outer lining).
Tubeless Inflator. Inflation system that makes the
inflation of tubeless tyres easier.
Beading. Operation which takes place during infla-
tion and ensures perfect centring between the bead
and the rim edge.
Bead pressing gripper. A tool intended for use
when mounting the upper bead. It is fitted so that
it grips the shoulder of the rim and holds the tyre
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a
c
b
d
e
g h
f
j
c
a
b
Operator's manual A 222
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