Improvements in Pneumatic Tyres for Bicycles.
Year: 1896

page_text: Date of Application, 2nd May, 1895--Accepted, 27th June, 1896
COMPLETE SPECIFICATION.
Improvements in Pneumatic Tyres for Bicycles.
We, BENSON PETER ALEXANDER, Manufacturer, and DAVID WATSON
ALEXANDER, Merchant, both of 5-7 Scott Street, in the City of Toronto, in
the County of York, in the Province of Ontario, Canada, 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 :-
Our invention relates to improvements in pneumatic tyres for bicycle or other
wheels and the object of the invention is to produce a pneumatic tyre, which is
cheaper lighter, more durable and of superior resiliency than those at present in
use and it consists essentially of a tyre comprising an outer tube or envelope for
the pneumatic tube, which is made of leather, and has its ends and longitudinal
edges suitably joined and of a supplemental band made of rubber having the
greatest thickness in the centre such band of rubber being arc-shaped in cross
section and designed to extend around the entire periphery of the leather
envelope and cover the end join of the same as hereinafter more particularly
explained.
Fig. 1, is a perspective view of portion of a pneumatic tyre constructed in
accordance with my invention showing it applied to the rim.
Fig. 2, is a circumferential part section.
Fig. 3, is a cross section showing the tyre under pressure.
Fig. 4, is an enlarged detail of the peripherial band.
In the drawings like letters of reference indicate corresponding parts in each
figure.
A is the rim, and B is the outer envelope, which is made of leather preferably
of long fibre, the circumferential edges of which are suitably joined at b within the
rim A and the ends of which are joined at 6' as indicated. The join may be of
any suitable form. C is a band made of rubber moulded into shape. The band C
is arc-shaped in cross section and thicker in the centre and gradually reduced thin
to both edges. The band C fits around the entire periphery of the envelope B
and covers the join b. The crescent-shaped band C is provided with a reinforcing
lining c, which is cemented to the interior thereof and is designed to form a perfect
means of connecting such band to the central portion of the periphery of the
leather envelope as indicated. The reinforcing lining c is made preferably of fine
silk or other fine textile material. D is the air tube.
The advantages of a pneumatic tyre constructed with a leather envelope and a
tread of rubber cannot be over estimated.
It is well known that leather is uniform throughout and has no weak spots. It
will, therefore, be seen that when the leather is made thin and provided with a
peripherial band of rubber as shown to form the tread, that such band will give
life and resilient qualities with no tendency to bulge or blow out as is the case
where rubber alone is used. Such a tyre as we describe will not puncture, will be
more durable and the tread will be perfect throughout and the band will protect
the join from ripping open.
The leather being made thinner than in ordinary leather tyres will add to the
resiliency while the band will prevent the leather from spreading circumferentially
as it otherwise would have a tendency to do when it becomes damp on the tread
were a band not provided.

page_text: The defect of rubber tyres is from the fact that weak spots form in them and
cause pin holes or blow outs. They puncture very easily and are too heavy to use
thick enough to be durable. The rubber tyre will also not maintain a uniform
size but will become uneven and is inuch more expensive than leather. The defect
of a leather tyre is that the end join will not hold without protection, dirt
accumulates on the tread and the leather is not sufficiently resilient when thick.
Leather also wears very quickly when in use as the tread comes in contact. with
the ground and water, dampness or atmospheric changes effect the leather, so that
it becomes weightier and stretches too large for the rim. As leather cannot be
made absolutely water proof the above defects are apparent. All these defects of
both rubber and leather are entirely obviated by the use of a leather envelope
with a tread consisting of a band of rubber such as described.
Another advantage is that when the tread or band of rubber becomes worn out
it can be replaced at a minimum cost so that the rider may have practically a new
tyre.
We might finally add that in rubber tyres the great wear takes place upon the
depression of the tyre as shown in Fig. 3, that is to say at the points of the rubber
where the greatest bulge takes place. As, however, in my tyre leather is used we
fiud in practice that such leather on account of its peculiar fibrous qualities is not
effected at the bulging points on both sides and consequently the life of the tyre
such as we describe is greatly increased.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :
1. In a bicycle or other wheel the combination with the rim, of a thin leather
envelope designed to fit thereon and held by the air tube when expanded in
substantially circular cross-sectional form and a tread of rubber encircling the
periphery of the envelope as and for the purpose specified.
2. In a bicycle or other wheel the combination with the rim, of a thin leather
envelope designed to fit thereon and having suitable joins for the ends and
circumferential edges and held by the air tube when expanded in substantially
circular cross-sectional form and a tread of rubber encircling the periphery of the
envelope and designed to cover and hold the end join from ripping as and for the
purpose specified."
3. In a bicycle or other wheel the combination with the rim, of a thin leather
envelope designed to fit thereon and held by the air tube when expanded in
substantially circular cross-sectional form and a tread consisting of a band
extending around the peripherial outer surface of the envelope or tyre and
formed crescent-shaped in cross section, the thickest portion of the crescent being
in the centre of the tread and such band being securely cemented to the envelope
throughout as and for the purpose specified.
4. In a bicycle or other wheel the combination with the rim, of a thin leather
envelope designed to fit thereon and held by the air tube when expanded in
substantially circular cross-sectional form and a tread consisting of a band
extending around the peripherial outer surface of the envelope or tyre and formed
crescent-shaped in cross section the thickest portion of the crescent being in the
centre of the tread and such band being securely cemented to the envelope
throughout and a reinforcing lining of fibrous material between the band and the
envelope as and for the purpose specified.
3000
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.