Improvements relating to Pneumatic Tyres.
Year: 1899

page_text: COMPLETE SPECIFICATION.
Improvements relating to Pneumatic Tyres.
I, JOSEPH THOMAS WICKS, of Ferndale, Tamworth Road, Gravelly Hill, Bir-
mingham, in the County of Warwick, India Rubber Expert and Factory Manager,
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 follow-
ing statement:―
The object of the present invention is to produce a strong and durable cover
for pneumatic tyres at a cheaper rate than heretofore.
To this end, I provide for the employment, in the cover, of the material which
is the more expensive, ri-the rubber, on an economical scale, and I make up
the deficiency in bulk with additional woven fabric or cloth which is compara-
tively cheap.
In carrying out my invention, the tyre is built up of several plies of cotton
duck or other suitable fabric, each of which is thoroughly impregnated with
rubber, preferably compounded rubber, that is to say, rubber contain-
ing vulcanizing elements and other ingredients. This rubber is applied
either in solution or in a plastic form. For thus thoroughly impreg-
nating the fabric, pressure or friction is employed by means of rollers,
preferably rotated at different speeds, when plastic rubber is used, until
the rubber is worked completely through and through the cloth. The plies thus
impregnated are then placed together in any desired number, to make the required
thickness of cover, and vulcanized. They thus become incorporated into one
solid body, by reason of the rubber, which permeates the whole, combining into
a mass. The addition of lines of sewing, or of rivets, will not be necessary to pre-
vent the separation of the plies, although such may be made, if desired. This
fabric may be used, as it is, for a cover, without the addition of further rubber,
but a thin layer or topping coat of rubber may be applied by means of the rollers,
in an uncured state, to the outside of the frictioned fabric, if desired, to form a
tread, and incorporated with the whole by vulcanization. This top layer may
be embossed to give it an irregular or non-slipping surface, ornamental or other-
wise. It may be mentioned that the topping may be either a narrow tread
extending longitudinally of the cover, or it may be of full width.
In the accompanying drawing, an effort has been made to illustrate this
invention,-
Fig. 1 being a diagram, in plan of a fragment of my tyre cover.
Fig. 2 is an edge view (enlarged) of a single ply of frictioned fabric, from
which the tyre cover is built up; and
Fig. 3 shews, in side view, a pair of rolls in the act of incorporating the rubber
with a strip of cotton duck.
On referring to Fig. 1, it will be seen that there are three plies of fabric, a, b,
and each supposed to be charged with rubber compound in the manner indi-
cated in Figs. 2 and 3.
C₁
In these figures, the black indicates the pressed-in rubber, and the white
circles indicate the threads of the fabric.

page_text: In Fig. 3, dd are calendering rollers for applying the rubber, the upper one
being supplied with rubber in a plastic condition from time to time, as the inter-
stices of the fabric are filled.
e is a rubber topping coat rolled onto the fabric of the cover, and incorporated
therewith by vulcanization.
The topping coat e is, as will be seen, merely wide enough to form a narrow
tread, but it may, if desired, be the full width of the cover. This topping coat
may be replaced by a narrow central tread, thickened towards the middle and
vulcanized to the cover.
f.ff, are three rows of stitches, to give additional solidity to the cover, if
desired.
A cover of this description is cheaper than an ordinary cover, inasmuch as it
contains much less rubber than a cover of equal weight, made in the usual way,
but it does not, on that account, suffer in quality, for it is excessively strong and
durable, and the layers and topping coat are not likely to come apart, like layers
attached by solution in the usual manner.
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:-
-
The manufacture of covers for pneumatic tyres in the manner above described,
by impregnating plies of cotton duck, or other suitable fabric with rubber, and
incorporating the whole into a solid body by vulcanization, whereby a strong
durable cover, at a cheap rate, is obtained, substantially as set forth.”
Dated this 1st day of Novembar 1899
NEWTON & SON,
Agents for the Applicant.