Improvements in Elastic Tyres and Rims for Wheels of Cycles.
Year: 1890

page_text: Date of Application, 10th Oct., 1890
Complete Specification Left, 5th June, 1891-Accepted, 11th July, 1891
PROVISIONAL SPECIFICATION.
Improvements in Elastic Tyres and Rims for Wheels of Cycles.
JOHN BOYD DUNLOP 50 Gloucester Street Belfast Veterinary Surgeon do
hereby declare the nature of this invention to be as follows:—
My invention relates to improvements in rims and tyres for wheels of cycles,
whereby the rims are made lighter and more rigid, the friction between the tyre
and the road surface is reduced and the speed of the cycle is increased.
I employ a continuous stripe or band of linen cloth or other similar inelastic or
non-stretching material which is inserted within the body of the elastic tyre, near to
its tread surface.
The direct object of this invention is to prevent expansion of the tread surface of
the tyre as it comes in contact with the ground, and to maintain the said surface
more firmly in position in resisting tractional strain.
The rim is thicker at its edges than it is at its sides towards its centre and is of
the usual semi-circular form.
The tyre is preferably tubular and somewhat of an oval or eliptical form with
the hole nearer to the rim surface than to the tread surface.
This invention may be applied to tubular, cellular, grooved, or solid elastic tyres
in which the weight of the rider is wholly, or mainly supported by means of the
rubber composing the tyre; but is not applicable to those hollow inflatable tyres in
which the weight of the rider is mainly supported through the medium of the air
compressed within the tyres.
Dated this 9th'day of October 1890.
JOHN BOYD DUNLOP.
COMPLETE SPECIFICATION.
Improvements in Elastic Tyres and Rims for Wheels of Cycles.
1, JOHN BOYD DUNLOP, of 50 Gloucester Street, Belfast Ireland, 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 :-
My invention relates to tyres for the wheels of velocipedes and other vehicles,
and more especially to clastic tyres of that kind or class wherein the weight is
wholly or partially supported by the-india-rubber or other elastic material forming
the said tyres.
The object of my said invention is to obviate or reduce the objectionable
spreading or expansion of the outer surface or tread, or that portion of the tyre
that comes in contact with the ground or other surface when the said tyre is
in use.
Elastic tyres of the kind or class above mentioned as hitherto made are especially
liable to such spreading or expansion.
In my improved tyre, the outer surface or tread, or that portion of the said
tyre which comes in contact with the ground or other surface, remains firmly,
or comparatively firmly in position under the action of a superimposed weight, or
whilst resisting tractional stresses, thereby greatly reducing the friction between
the said tyre and the ground. or other surface and enabling the propulsion or
traction of the vehicle to be more easily effected, and greater speed to be
attained with a less expenditure of force (as for instance in the case of veloci-
pedes or the like) than is possible with tyres of this kind or class as hitherto

page_text: made. This result is obtained by combining with the tyre, a sirip or band of
linen cloth or similar material which will prevent in a great measure lateral
expansion of the said tyre.
In the accompanying drawing I have shown how my said invention may be con-
veniently and advantageously carried into practice.
Figure 1 is a side elevation partly in vertical section showing a portion of the
rim of a velocipede or other wheel, and a hollow or tubular elastic tyre with my
improvements applied thereto.
Figure 2 is a transverse section on the line a. Figure 1.
Like letters indicate corresponding parts in these two figures.
A is the rim of the wheel; B, B are some of the spokes thereof; C is an india-
rubber or other clastic tube which forms the main portion of the tyre and which is
secured upon the rim A in any convenient manner.
D is a strip or band of linen, cloth or other non-elastic material, or only slightly
elastic material, that is to say, material which will stretch or yield but slightly, and
will therefore, prevent undue spreading or expansion of the tyre. The said strip or
band D is cemented to, moulded and vulcanized with, or otherwise firmly secured
to the tube C, and extends around the periphery thereof. C' is an outer or pro-
tective covering or layer of india-rubber or other suitable material cemented or
otherwise firmly secured over the continuous strip or band D, and intended to
withstand the weap caused by friction against the ground or other surface when the
tyre is in use.
In some instance the said continuous strip or band D is cemented to, or moulded
and vulcanized with the said outer or protective covering C, and the said band or
strip and covering re then firmly secured by cement or otherwise to the india-
rubber or other tube C.
I prefer to form the said tube C slightly oval or elliptical in transverse section
and to place the hole (which is preferably of a corresponding shape in transverse
section to the said tube) nearer to the inner surface, or that surface which is
intended to come in contact with the rim of the wheel than to the outer surface or
tread thereof.
Although I have hereinbefore described my said invention as applied more
particularly to a hollow or tubular india-rubber or other clastic tyre, it is obvious
that my said invention is also advantageously applicable to cellular, grooved, solid,
or other suitable forms of elastic tyres. My improved tyre may be first built up
and afterwards placed in position upon the wheel of the velocipede or other vehicle,
or it may be built thereon.
My invention is not intended to be applied to hollow inflatable tyres in which the
weight of the rider is mainly supported through the medium of air compressed in
the said tyres.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
First. An elastic tyre having a strip or band of linen, cloth or other non-elastic
or but slightly elastic material surrounding the periphery thereof, or enclosed
therein near the periphery, with or without the outer protective covering, substan-
tially as, and for the purposes hereinbefore specified.
Second. The improved tyre constructed substantially as described with reference
to the accompanying drawing for the purpose specified.
Dated this 4th day of June 1801
JOHN BOYD DUNLOP.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.