Improvements in or relating to Pneumatic Tyres.
Year: 1899

page_text: Date of Application, 4th Feb., 1899
Complete Specification Left, 1st Nov., 1899-Accepted, 16th Dec., 1899
Improvements in or relating to Pneumatic Tyres.
A communication from ALBERT DROUET, Engineer, of Levallois-Perret, in
France,
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
This invention relates to a detachable pneumatic tyre applicable to vehicles
of all descriptions, and especially to cycles, motor cycles and motor cars, etc., the
said tyre being adaptable to rims of all shapes, whether semi-circular or otherwise.
This improved pneumatic tyre is composed of two distinct elementary parts,
riz., the air chamber and the cover or envelope in conjunction with a rim, and the
special feature of the invention lies in the construction of the cover by a com-
bination of crossed threads as hereinafter described.
The outer cover consists of the ordinary combination of canvas and rubber its
side edges, however, being united together by means of cross thread connections,
leaving however, a free space between the said edges.
These cross connections are made of layers of free threads crossing each other
at any desired angie, thus individually acting in opposite direction. By these
means a closed circular tube is obtained. The said threads may, of course, be
substituted by cords, strands, etc., without altering the principle of the invention.
It will now be easily understood that by moving aside in any place the threads
of which the connection consists, to do which is easy when they are not drawn
taut by the pressure of a fully inflated air chamber, inside the cover, it is possible
to make an opening sufficiently large to draw out the slake or partially deflated
air tube, for the purpose of repair or for any other purpose.
The manner of fixing and of maintaining the tyre on the rim will now be
described.
The circular cover having been placed on the rim and receiving a pressure from
within, by air being pumped into the air-chamber, will contract, and the diameter
of the circle formed by the cover will gradually diminish, on account of the threads
or cords, forming the cross connections being acted upon by said pressure; so
that the angle which they form with the edges of the cover to which they are
attached becomes more and more obtuse, this action causing the annular con-
traction of the whole tyre, and thereby, securing a closer and intimate contact
of the tyre upon the rim along its whole periphery, in proportion as the pressure
in the air chamber increases, until it is impossible to detach it without first de-
flating the inner tube or the tyre.
Thus the air pressure acting from within along the whole circumference will
hold the tyre firmly on the rim by means of cross connections as above described.
Dated this 4th day of February 1899.
BOULT & WADE,
Agents for the Applicant,

page_text: Improvements in or relating to reumatic lyres
A communication from ALBERT DROUET, Engineer, of Levallois-Perret, in
France,
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and as-
certained in and by the following statement:--
This invention relates to a detachable pneumatic tyre applicable to vehicles
of all descriptions, and especially to cycles, motor cycles and motor cars, etc., the
said tyre being adaptable to rims of various shapes either semi-circular or
otherwise.
To facilitate the description of the invention reference will be made to the
accompanying drawings, in which:
Figure 1 shows a perspective view of a tyre constructed in accordance with this
invention, it being shown detached from the rim, and the air chamber partially
deflated.
Figure 2. shows the tyre mounted on the rim and the air chamber inflated.
Figure represents the tyre detached with a portion of the inner air chamber
or tube pulled out for the purpose of repairs.
The improved pneumatic tyre is composed of two distinct elementary parts,
riz., an air chamber or inner tube c and a cover or envelope and the special
feature of the invention lies in the construction of the cover in which a series
of crossed threads, strips or the like are employed as hereinafter described.
The outer cover b consists preferably of the ordinary construction of canvas
and rubber, its side edges however being united together by cross connections
of threads, cords, strips or the like f, g, h, i, leaving however, a space between
the said edges, as represented in Figure 1.
These cross connections are made of layers or series of free threads crossing each
other at an angle, thus individually acting in opposite directions. By this means
a closed circular tube is obtained. The threads may, of course, be substituted
by cords, strands or the like without affecting the principle of the invention.
It will now be easily understood that by moving aside in any place the
threads f g h of which the connection consists-to do which is easy when ther
are not drawn taut by the pressure of a fully inflated air-chamber c inside the
cover it is possible to make an opening sufficiently large to draw out the
slack or partly deflated air tube, for the purpose of repair or for any other purpose.
The manner of fixing and maintaining the tyre on the rim a, which is repre-
sented here by way of example, as a rim with sides curving upwards but which
may be of other suitable shape will now be described.
The circular cover with its inner tube having been placed on the rim a and
receiving a pressure from within, by air being pumped into the air chamber c,
will contract and the inner diameter of the circle formed by the cover will
gradually diminish on account of the threads or cords forming the cross connec
tions being acted upon by said pressure so that the angle which they form with the
edges of the cover to which they are attached becomes more and more obtuse,
this action causing the annular contraction of the whole inner circumference
and thereby securing a close and intimate contact of the tyre upon the rim along
its whole periphery in proportion as the pressure in the air chamber increases,
until it is impossible to detach it without first deflating the inner tube of the
tyre.
Thus the air pressure acting from within along the whole circumference will

page_text: hold the tyre firmly on the rim by means of the cross connections as above
described.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what manner
the same is to be performed I declare that what I claim is-
1. A pneumatic tyre comprising an inner air chamber and a cover the edges
of which are united by a series of threads, strips, cords or the like crossing each
other at an angle in such manner that when the inner air chamber is inflated the
angles which these threads form with the lateral edges of the cover become more
and more obtuse in consequence of the moving apart of the edges of the cover,
thereby securely holding the tyre on the rim of the wheel.
2. A pneumatic tyre cover provided with a series of threads, cords, strips or the
like connecting the edges of the cover together and crossing each other at an
obtuse angle, substantially as described.
3. The complete pneumatic tyre substantially as described and illustrated in
the accompanying drawings.
BOULT & WADE,
Agents for the Applicant.