Improvements in the Manufacture of Elastic Tyres and Protective Coverings for the Wheels of Carriages, Cycles, and other Vehicles.
Year: 1896

page_text: Date of Application, 14th July, 1895
Complete Specification Left, 9th Apr., 1897-Accepted, 22nd May, 1897
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Elastic Tyres and Protective
Coverings for the Wheels of Carriages, Cycles, and other
Vehicles.
I, JOSEPH VINER JOHNSON, of Coneycroft, Selborne, in the County of Hants,
Gentleman, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in the manufacture of elastic tyres and
protective coverings for the wheels of carriages, cycles, and other vehicles, and it
is designed to render such tyres or coverings less liable to injury by punctures, or
cuts, than are tyres of ordinary manufacture.
To this end, I construct the elastic tyre, or protective covering, in such a way
that it is in a state of natural permanent compression, the degree of such compression
being greatest at the tread or wearing face where the tyre bears on the ground.
Owing to this natural state of compression existing in the mass of the cover
or tyre, it offers great resistance to either cut or puncture. Should, however,
either occur, the tendency is for it to close up, not for it to spread or open as in
ordinary tyres, and coverings.
In carrying out my said invention, form or build up the tyre or covering, by
moulding, or otherwise, so that its natural curvature is sharper, that is, of less
radius, than the curvature of the circumference of the wheel to which it is to be
applied, and I so arrange it that the part which is to form the wearing face or
tread is outermost during such manufacture.
When such a tyre or covering is applied to. the wheel it is intended for, it
requires to be unbent somewhat, owing to its natural sharp curvature, and this
unbending compresses the particles thereof, especially towards the wearing face or
tread, and causes them to tend to come together.
According to one arrangement, I form or build up the tyre or covering upon a
strip of canvas, or other suitable non-elastic material, wound helically around a
mandrel, the necessary coating or thickness of indiarubber, or rubber composition,
being applied thereto in any suitable manner. In unwinding such a strip, it may
be necessary to cut the same in a helical direction between its convolutions or folds
owing to adherence of the rubber on adjacent portions thereof.
To apply the indiarubber, the mandrel, with the canvas or the like thereon, may
advantageously be placed in a mould having a helical groove of suitable cross
section, and the rubber or composition be run into such groove. A strip of metal,
or a length of wire, may also be wound around the mandrel, or inside the mould, to
form a division between the adjacent parts of the finished tyre.
Instead of moulding the rubber, or composition, it may be applied to the canvas,
or the like, in successive coatings or layers.
Another method of obtaining a natural compression in the tyre or covering, is
to make the same as though it were to fit a wheel smaller than that for which it is
intended. It is then cut and applied to the wheel, thereby causing an unbending
and consequent permanent compression. A filling piece must, in this case, be
employed to compensate for the greater length of circumference.
My invention is especially applicable to the thick solid tyres of carriages and
other comparatively heavy vehicles, although it may advantageously be applied

page_text: to other solid tyres, as well as to protective coverings for pneumatic or cushion
tyres.
Dated this 14th day of July 1896.
ERNEST DE PASS,
Chartered Patent Agent,
78, Fleet Street, London, and 5A, Market Street, Nottingham,
Agent for the Applicant.
Improvements in the Manufacture of Elastic Tyres and Protective
Coverings for the Wheels of Carriages, Cycles, and other
Vehicles.
I, JOSEPH VINER JOHNSON, of Coneycroft, Selborne, in the County of Hants,
Gentleman, 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, reference being had to the accompanying drawings
and to the letters and figures marked thereon, that is to say:
This invention relates to improvements in the manufacture of elastic tyres, and
protective coverings, for the wheels of carriages, cycles, and other vehicles, and it
is designed to render such tyres, or coverings, less liable to injury by punctures or
cuts than are tyres of ordinary manufacture.
Elastic tyres, or coverings, as now made, have the tendency to gape or open at
the places or points where cut, or punctured, the consequence of which is that the
cuts or punctures rapidly increase in size, and the deterioration or complete
destruction of the tyre is only a matter of a short time, and frequently leads to
serious accidents.
Now, the object of my invention is to render such tyres, or coverings, more
durable by imparting to their outer or wearing surfaces, a strong tendency to close
any cuts or punctures that may occur, and so prevent any further opening thereof,
or deterioration of the tyre.
To this end, I construct the elastic tyre, or protective covering, in such a manner
that, when placed on the wheel, it is in a state of permanent compression, the degree
of such compression gradually increasing from the base of the tyre to a maximum
at the tread or wearing surface where the tyre bears on the ground.
A convenient method of carrying out my invention consists in moulding, or
otherwise forming, the tyre, or protective covering, of plastic rubber, or rubber
composition, on an inextensible band webbing or strip of canvas, or other suitable
material, winding the same spirally on an appropriately shaped mandrel of a
diameter smaller than that of the finished tyre, then placing such mandrel in a
mould of appropriate shape so as to slightly compress the plastic material of the
tyre, and finally vulcanizing such tyre in the usual manner.
The accompanying drawings shew, by way of example, means or appliances
for use in the manufacture of tyres made according to my invention.
Fig. 1 is a longitudinal section of the mandrel, and Fig. 2 of the mould.
Fig. 3 shews the mandrel with the plastic rubber for the tyre wound thereon,
and inserted in the mould..
Fig. 4 is a cross section of the finished tyre, and
Fig. 5 a longitudinal section of the same.
Fig. 6 shews a coiled length of tyre ready for use.
Fig. 7 shews a protective covering for a pneumatic tyre for carriages or motor
cars.

page_text: C
In carrying out my invention, I take a strip, webbing or band a, of canvas or other
suitable inextensible material of the requisite width, which may, or may not, be
previously coated with plastic rubber composition, and form thereon a rough tyre b
of the necessary thickness. I then wind it upon the mandrel c which is advan-
tageously made hollow aud of smaller diameter than that of the wheel to which
the finished tyre is to be applied. I may sometimes provide a spiral rib or thread c¹
on such mandrel, as shewn at Fig. 1, of a section to suit the base 6 of the tyre.
This base which is usually slightly wider than the tread portion, is placed inner-
most on the mandrel between adjacent portions of the spiral rib or thread c.
The mandrel, with the roughly shaped tyre of plastic rubber composition thereon,
having the strip of inextensible material at or near its base, is next placed in a
mould e made in sections, or halves, and provided with a spiral rib or thread e¹ of a
pitch corresponding to that on the mandrel. The recess or groove between the
turns of the spiral rib or thread is made to suit the conformation or shape of the tread
of the tyre. The mould is then closed and placed in a press, wherein it is subjected to
pressure so as to slightly compress the plastic rubber material. The tyre so formed
is then vulcanized in the usual manner, the superfluous rubber, due to the
vulcanizing process, escaping into grooves or channels e, formed for the purpose
in the mould e. The tyre is then removed from the mould and trimmed.
I may, however, dispense with the use of the mould, and after winding the
tyre on to the mandrel vulcanize it in the usual manner.
In some cases, I may wind the strip of inextensible material directly between the
spiral rib or thread on the mandrel, and then apply the rubber compozition to form
the rough tyre.
In applying the tyre to the wheel which is, as already stated, of larger diameter
than the mandrel used in its manufacture, the tyre requires to be uncoiled to some
extent. As the strip of inextensible material, at or near the base of the tyre, is
incapable of stretching, it will be apparent that, on uncoiling the tyre in order to
apply it to the rim or felloe of the wheel, the molecules of rubber, or rubber
composition, composing such tyre must become compressed, and that the degree of
compression will increase from the base to the tread of the tyre. This compression
of the molecules which is greatest at the tread, causes the tyre to close up if it
should be cut or punctured. The tyre thus manufactured may be fitted on the rim
of the wheel in one length, its ends being then cemented together, or otherwise
joined; or the ends may be joined previously to the tyre being applied to
the rim.
The manufacture of coverings for pneumatic tyres with an inserted strip, or
strips, of inextensible material, is essentially the same as that above described with
reference to elastic tyres, but I find it best to first produce narrow strips in the
manner above mentioned, and then to cement or join them together at their
longitudinal edges, as at Fig. 7, so as to obtain the requisite width. By this mode
of manufacture, I obtain greater and more uniform compression of the molecules of
the rubber, or rubber composition, than when forming the covering in a single strip.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same may be performed, I wish it to be understood
that I am aware that prior to my invention elastic tyres have been moulded to a
diameter smaller than the wheel to which they are to be applied, but such tyres
are not provided with a strip of inextensible material at their base, and they have
therefore the tendency to stretch at the base rather than compress at the tread,
I therefore do not broadly claim the moulding of elastic tyres to a diameter
smaller than that of the wheels to which they are to be applied, but what I
claim is:-
1. The improved method of manufacturing elastic tyres and protective coverings
for the wheels of carriages, cycles, and like vehicles, substantially as set forth.
2. The manufacture of elastic tyres and protective coverings for vehicle wheels,
by applying a strip of inextensible material at or near the base, winding the tyre

page_text: in a spiral of relatively small diameter, and vulcanising it in that condition, so that
when the coils are opened out the rubber will be in a state of compression.
3. The method or process, substantially as described, of manufacturing elastic
tyres and protective coverings for vehicle wheels, by backing the rubber, or similar
material, of which the tyre is composed, with canvas webbing or similar inextensible
material, winding it upon a mandrel bearing a helical channel, enclosing this in a
mould the inside of which bears a corresponding helical channel, and vulcanising.
4. An elastic tyre for vehicle wheels manufactured substantially as herein before
described.
5. An elastic protective covering for pneumatic tyres, manufactured substantially
as hereinbefore described, and as shewn with reference to Fig. 7 of the drawings.
6. An elastic tyre for vehicle wheels, comprising a solid body of rubber or
similar elastic material, such as b, and a backing of inextensible material such as a,
substantially as and for the purpose described and illustrated in the accompanying
drawings.
Dated this 9th day of April 1897.
ERNEST DE PASS,
Chartered Patent Agent,
78 Fleet Street, London, and 5ª Market Street, Nottingham,
Agent for the Applicant.