Improvements in Tyres for the Wheels of Velocipedes and other Vehicles.
Year: 1891

page_text: Date of Application, 5th Aug., 1891
Complete Specification Left, 10th May, 1892-Accepted, 18th June, 1892
PROVISIONAL SPECIFICATION.
Improvements in Tyres for the Wheels of Velocipedes and other
Vehicles.
I, JOHN BOYD DUNLOP, of 50 Gloucester Street, Belfast, Ireland, Veterinary
Surgeon, do hereby declare the nature of this invention to be as follows :-
My invention relates to tyres for the wheels of velocipedes and other vehicles
and more especially to hollow inflatable tyres of the kind or class known as
pneumatic tyres.
The object of my said invention is to provide an improved air-proof tube for use
in pneumatic tyres which will not allow the air or other gas with which the said
tube is inflated to escape in the event of the said tube becoming punctured or cut.
In carrying my said invention into practice I form the said air-proof tube of two
layers of india-rubber or other suitable air proof material cemented or otherwise
joined together.
One of these layers is larger than the other and whilst being cemented or other-
wise secured together they are subjected to mutual compression and expansion.
For this purpose I prefer to construct the inner or smaller layer in the form of a
tube and to expand or distend it to a suitable extent by inserting therein another
air-proof tube of suitable dimensions and inflating the latter, or by means of rods or
bars, inserted into the inner layer or tube and forced asunder by means of screws
wedges or the like, or I expand the said inner layer or tube in any other convenient
manner. When the said inner layer or tube is sufficiently expanded or distended
the outer or larger layer is laid on and cemented or otherwise secured thereto.
Upon the inner or smaller expanded tube or layer being permitted to collapse it
contracts and compresses or puckers the outer or larger layer and thereby effectually
closes any holes or punctures which may be formed therein as the result of accident,
and prevents the escape of the gas or air from the said tube when used in a tyre.
I prefer to employ very pure india-rubber for the outer layer which may or may
not be vulcanized. When it is desirable to compress or pucker the outer layer still
further I invert the tube.
Dated thin 5th of
1901
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Tyres for the Wheels of Velocipedes and other
Vehicles.
I JOHN BOYD DUNLOP of 50 Gloucester Street, Belfast Ireland Veterinary
Surgeon 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 hollow inflatable tyres of the kind or class known as
pneumatic tyres.
The object of my said invention is to provide an improved air-proof tube for use
in pneumatic tyres which will not allow the air or other gas with which the said
tube is inflated to escape in the event of the said tube becoming punctured or cut.
In carrying my said invention into practice I form the said air-proof tube of two

page_text: layers of india-rubber or other suitable air-proof and elastic material cemented or
otherwise joined together.
One of these layers is larger than the other and whilst being cemented or other-
wise secured together they are subjected to mutual compression and expansion.
For this purpose I prefer to construct the inner or smaller layer in the form of a
tube and to expand or distend it to a suitable extent circumferentially and longi-
tudinally by inserting therein an auxiliary air proof tube somewhat longer and of
larger diameter than the said inner layer and then inflating the said auxiliary tube.
The auxiliary air proof tube is constructed of india rubber and canvas and closed
at both ends by means of an air proof cap, so that it may be inflated.
Or I may
achieve the same purpose by inserting rods or bars into the inner layer or tube and
then forcing them asunder by means of screws wedges or the like or I expand the
said inner layer or tube in any other convenient manner. When the said inner
layer or tube is sufficiently expanded or distended the outer or larger layer is laid
on and cemented or otherwise secured thereto. When the two tubes are cemented
together the auxiliary tube or the rods and wedges are withdrawn.
Upon the inner smaller expanded tube or layer being permitted to collapse by
the withdrawal of the auxiliary tube or rods and wedges it contracts and compresses
or puckers the outer or larger layer and thereby effectually closes any holes or
punctures which may be formed therein as the result of accident and prevents the
escape of the gas or air from the said tube when used in a tyre.
I prefer to employ very pure india-rubber for the outer layer having a small
percentage of sulphur. When it is desirable to compress or pucker the outer layer
still further I turn the tube inside out.
The ends of the tube are closed or joined in the usual way by a band of india-
rubber and cement or by inserting one end of the tube into the other end of the
same.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
An improved air-proof tube for use in pneumatic tyres constructed in the manner
substantially as described and for the purpose specified.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.