Improvements in and connected with Pneumatic Tyres.
Year: 1892

page_text: COMPLETE SPECIFICATION.
[Communicated from abroad by WALTER BADENACH HARDY, of The Gables,
Babcock Street, Brookline, Norfolk County, Massachusetts, United States
of America, Rubber Manufacturer.]
Improvements in and connected with Pneumatic Tyres.
I, HENRY HARRIS LAKE, of the firm of Haseltine Lake & Co., Patent
Agents, 45 Southampton Buildings in the County of Middlesex, do hereby
declare the nature of this invention and in what manner the same is to 'be
performed to be particularly described and ascertained in and by the following
statement:
This invention relates to inflatable tyres for bicycles and tricycles, the object
being to so construct them as to lessen the danger of leakage of air and to facilitate
repairs.
The
My invention consists in a tyre having an inflatable inner tube, and a wrapper
suitably secured to the rim with flaps each side thereof adapted to be folded
successively around the inner tube while in position on the wheel rim, such flaps
thus forming, outside of the inner tube, a body or tread portion made up of two
thicknesses or flaps successively applied and secured. These flaps are of such
breadth as to reach around the inner tube and to the opposite edges of the rim, and
are made of vulcanized rubber lined or reinforced by firm flexible canvas.
rubber is vulcanized in a mould while the wrapper is bent around a core or form*
corresponding to the inflated inner tube, so that its normal tendency is to clasp the
tube. The core or form is a continuous clastic body circular in cross section, or
in two rigid semi-circular parts, so that it may be removed when the flaps have
been lifted or turned back. When the inflatable tube is substituted for the core
the flaps are restored to position and secured in any suitable manner as by cement,
and fitting
hooks or lacings. Marginal beads formed along the edge of the wrapper
into grooves at the inward-turned edges of the wheel-rim, hold the parts firmly
when the tyre is inflated. The mould is grooved to receive the rubber which
forms these beads. 1 apply a much thicker body of rubber on the outer flap than
on the inner, to constitute the tread surface of the tyre, and I prefer to use,
beneath the wrapper proper, an extra strip of rubber and canvas lying along the
valley of the rim, to give special firmness to this base of the tyre.
In the drawings,
Figure 1 represents, in cross section, the mould the core, and the rubber and
canvas wrapper being vulcanized between them.
Figure 2 is a transverse section of the wheel rim and tyre complete.
A Figure 2 represents the wheel-rim having a suitable transverse curvature to
receive in its sunken periphery my improved tyre. B is the inflatable inner tube;
made of vulcanized rubber in any approved form, either a plain tubular ring or
one of the so-called "nonpuncturable" tubes in which the outermost portion,
nearest to the tread, is held under compression, so that any small perforations
made therein will be closed by the internal pressure.
CD is the wrapper to which my invention more particularly relates, C being the
innermost flap or fold formed of canvas coated with rubber on its outer surface,
and D the much heavier outer flap or fold, made of a continuation of the same
I furnishi
canvas with a thick body of rubber secured thereon by vulcanization.
an extra strip, F, of rubber and canvas beneath the wrapper proper and lying"
along the valley of the rim, to give additional body to this portion of the wrapper.
This wrapper is secured to the concave rim A in a firm manner, either by
vulcanizing or cementing it along its longitudinal centre to the concave face of the
rim, or by riveting it thereto, or by such other means as may be preferred. The

page_text: vulcanizing to the wheel rim may be readily effected by first coppering the face of
the rim, then applying thereto the rubber face of the parts C or F while in the
raw state, then pressing this central part of the wrapper to the rim by the curved
core E, then wrapping the flaps CD successively around the. core, and enclosing
the whole in the circular mould M, and subjecting the rubber to the vulcanizing
process.
I prefer to form the wrapper, as illustrated in Figure 1, not upon the wheel rim,
but on a concave ring G, having the same diameter and transverse curvature as the
body of the wheel rim, upon which the tyre is to be used. This ring G fits into a
recess formed in the mould M to receive it, and the wrapper is supported during
its construction by the ring and the internal core E. The rubber is prevented
from adhering to the concave ring G by the use of powdered talc, as is well known
to rubber workers. The flaps of the wrapper are similarly prevented from
adhering together during vulcanization. The mould is in two parts, each grooved
circularly to receive between them the wrapper enclosing the core and mounted ir
the ring G and when they are placed in the heater for a sufficient length of time the
rubber is properly vulcanized.
The vulcanizing of the rubber while the wrapper is wrapped around the core
and confined by the mould, fixes its normal position to coincide with that which it
occupies when in use, or in other words gives it a permanent tendency to retain the
same form in cross section which it had when vulcanized. Hence the flaps will
tend to embrace the inner tube, and a moderate force will hold them in place, after
said tube has been introduced in place of the core E around which the wrapper was
formed. In removing the core the edges of the flaps will be loosened from the
rubber beneath them, and they will be turned back enough to release the core and
insert the deflated tube; then the tube may be wholly or partially inflated and the
flaps wrapped around and secured to it.
The drawings represent the means I prefer to use, for securing the edges of the
wrapper to the wheel rim. The edges a of the rim are hooked or turned inwardly
as in Figure 2, and ribs or beads are formed in the rubber of the wrapper to fit
into the marginal grooves of the rim. One of these ribs or beads will be along the
extreme edge of the outer flap and the other at a line opposite thereto, about over
the edge of the inner flap. Each half of the mould is grooved to receive the rubber
which forms these ribs or beads,.as seen in Figure 2.
When the tyre is deflated the ribs or beads may be readily introduced into and
removed from the marginal grooves a of the rim; but when inflated they are firmly
held, and the firmness of the hold increases with the pressure.
It will be observed, as a peculiarity of this tyre that it does not need to be
removed from the wheel-rim in case of injury to the inner tube, since it is
practicable to open up the wrapper and repair the inner tube when occasion
requires, and then to replace the folds of the wrapper without having, in any
degree, loosened its hold upon the wheel-rim. The great advantage of a con-
struction which permits this is obvious.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. In a pneumatic tyre, an inflatable inner tube in combination with a wrapper
formed of canvas and rubber, the flaps of which are successively wrapped around
the outer face of the inner tube and secured around the same, so that a tread
portion is provided made up of the superposed flaps of said wrapper embracing the
inner tube, substantially as set forth.
Hofe
2. The concave metallic rim A, the inflatable inner tube B, the wrapper secured-
longitudinally along said rim and having flaps CD each extending from the edge
of the rim around the tube B and successively secured thereon, substantially as
set forth.
3. The concave rim A having inward-turned edges a constituting marginal
.

page_text: grooves,
in combination with an inflatable inner tube and with the wrapper C D
permanently secured to the rim, and having ribs or beads r fitting into said grooves,
substantially as and for the purpose set forth.
Dated this 30th day of August 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.