Year: 1894

page_text: Date of Application, 21st June, 1894
Complete Specification Left, 22nd Apr., 1895-Accepted, 24th May, 1895
I, THOMAS SLOPER of 11, 12, 14 and 15 Brittox Devizes in the County of
Wilts, House Furnisher, do hereby declare the nature of this invention to be as
follows:-
This invention relates to certain improvements in or relating to pneumatic tyres
and the object of my invention is to produce a tyre that
less liable to puncture
than those at present in use.
In order to attain this result 1 make the tyre of india rubber combined with a
flexible fibrous material or fabric and I vulcanize the rubber in a mould of peculiar
construction which causes the tyre to take a corrugated or intended form on the
tread surface and at each side. Thus a corrugation crossing the tread surface of
the tyre at right angles is followed by two corrugations one on each side of the
tyre, then by another crossing the tread surface and so on alternately all round the
circumference of the tyre.
It will be obvious that the outer circumference or tread surface of a tyre con-
structed in this manner is of considerably greater area and contains more material
than a tyre made with an even surface and moreover when deflated the air
space inside the tyre is less than is the case with an ordinary tyre of the same
size. When the tyre is inflated the air pressure forces out the indented portions
of the tyre and as the fibrous thread or fabric prevents the tyre from stretching
the effect is to compress the rubber forming the tyre and thus render it less liable
to puncture.
I am aware that tyres have been made with the inside rubber under com-
pression by turning a tube or cover inside out after vulcanizing but this method
puts extra strain on the fabric and moreover although one side of the rubber is
under compression the other is under tension in which condition it is particularly
liable to puncture.
In my arrangement the whole of the rubber of the tyre outside the wheel
rim is more or less under compression (as well as the fabric) when the tyre is
inflated.
In case of the tyre coming in contact with a small stone or obstruction on
the road the free or extra material in the tyre allows the latter to absorb the
obstruction thus economizing power. Instead of canvas I prefer to use transverse
fibrous threads to strengthen and limit the expansion of the tyre, and when the
rubber is under compression longitudinal threads are not absolutely necessary.
This invention is applicable to either single tube or detachable tyres.
In order to transmit the driving power more directly from the wheel rim to the
road surface and to prevent a resisting wave forming in front of the tyre I some-
times use diagonal or slanting threads running from the tread surface upwards and
backwards. These slanting threads may be arranged in an extra cover which may
be used over the tyre, or the slanting threads may be vulcanized into the tyre
together with the transverse threads before mentioned in which case the whole
may be so arranged that the transverse threads limit the expansion of the
tyre and the diagonal threads have a little strain only when the tyre is inflated.

page_text: This invention is capable of considerable modifications for instance the tyre may
be made with corrugations ou the trend surface only, or with corrugations on each
side alternately so that the portion of the tyre that is outside the wheel rim takes
a zig-zag form when deflated, or circular depressions may be made in various parts
of the tyre the object being to vulcanize the tyre in such a form that its surface
aren is farger when deflated than when inflated."
Dated this 21st day of June 1894
голиши со гноиндий тугез.
1, THOMAS SLOPER, of 11, 12, 14, and 15 Brittox, Devizes in the County
of Wilts, House Furnisher, 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 :-
This invention relates to certain improvements in or relating to pneumatic tyres
and has for its object so to construct a tyre that when it is inflated the rubber at
the trend surface shall be in compression and thereby rendered less liable to
puncture than a tyre as ordinarily constructed.
When an ordinary pneumatic tyre is removed from the vulcanizing mould the
rubber contracts or shrinks, and when the tyre is inflated it stretches again, con-
sequently the rubber of the tyre is under slight teusion at every part in which
condition it is particularly liable to puncture. A thorn or sharp substance would
as a rule only enter a slight distance into the tyre during the first revolution of the
wheel, but it would enter a little farther each successive revolution until at last the
air tube would be punctured, consequently what is required is to compress the rubber
of the outer cover or skin of the tyre, that is to say the part which makes actual
contact with the ground so as to render it less liable to take up a thorn or other
article likely to puncture the air tube, and so that it would have a tendency to
force the thorn out if it should enter, and this, as above set forth, is the object of
my present invention.
The invention will be best understood by reference to the accompanying
drawings in which :—
Figues and 2 are respectively a side elevation and a plan of portion of a
pneumatic tyre constructed according to this invention.
Figures 3 and 4 are transverse sections or sectional elevations taken respectively
on the lines 3-3 and 4-4 of Figure 1.
Figure 5 is a side elevation of portion of an alternative form of the tyre.
Figures 6 7 8 and 9 are transverse sections or sectional elevations taken
respectively on the lines 6-6, 7-7, 8-8 and 9-9 of Figure 5, and
Figure 10 illustrates a modification.
All the drawings represent the tyres in their deflated condition; there need be
little or no difference in the appearance of these improved tyres and other pneumatic
tyres when in their inflated condition.
Like letters indicate like parts throughout the drawings.
In order to attain the result above set forth I make the tyre A of indiarubber
and flexible fibrous material or fabric 13 the Intter for restraining or limiting the
expansion of the tyre; any suitable material may be used for this purpose but I
prefer a material which is more or less inextensible in one direction and free to
stretch in the other direction. I then vulcanize the rubber combined with the
restraining material 13 in a mould of peculiar formation which causes the tyre to
take a corrugated or indented form at either the tread surface alone, or, as shown

page_text: in the accompanying drawings, at both the tread surface and the sides of the
tyre A. In Figures 1, 2, 3 and 4 the tread-surface corrugations are lettered A'A
A indicating the projecting parts hereinafter termed "tread-projections" and
A³ the hollows between the projections hereinafter termed "tread-recesses," the side
projections are lettered A3 and the side recesses A'. In this manner as shown in
the drawings, each tread-recess A' crossing the tread surface at right angles
coincides with two side projections A³ one on each side of the tyre and is imme-
diately preceded and followed by a tread projection A each of which coincides
with two side recesses A' one on each side of the tyre and so on throughout the
circumference of the tyre. The arrangement of the side corrugations may
however be modified for example as shown on a reduced scale in Figure 10 the
corrugations on one side of the tyre instead of corresponding with those at the
opposite side may alternate therewith so that the portion of the tyre outside
the wheel rim would take a zig-zag form when deflated.
It will be obvious that the outer circumference or tread surface of the before
described tyre is of considerably greater area and contains more material than a
tyre made with an even surface and moreover when deflated the air space inside
the tyre is less than that of an ordinary tyre of the same size; the material
however is homogeneous throughout the tyre while it is in this deflated condition.
When the tyre
inflated the air pressure forces out the indented portions or
recesses AA and thereby draws in the projections A' A³ of the tyre and as
the restraining material prevents the tyre from stretching, the effect is to
compress the rubber forming the tyre and thus render it less liable to puncture.
I prefer that the width of the restraining material should be uniforin throughout
the circumference of the tyre A, so that upon inflation the tyre may be of uniform
cross sectional area at all parts. When however, for giving a greater degree of
compression of the rubber at the tread, than would otherwise be obtained the
corrugations A A A³ A are so deep or close together that the pressure of air
ordinarily used for inflating the tyre would be insufficient to cause the corru-
gations to quite disappear, the restraining material may if desired be a little
wider at the parts corresponding with the tread recesses A² in order that such
recesses shall disappear when the tyre is inflated.
In the accompanying drawings I have represented the tyres A as provided at
the edges with wires C wherewith to secure them to the wheel rims but I do
not restrict myself to this or any other particular means of fastening, as almost
any kind of fastening or attachment is applicable to tyres made according to
my invention.
I would point out however, that when wire or other inextensible
material is used at the edges of my improved tyre or cover the effect of inflation is
somewhat different to that which occurs with ordinary saddle-shaped covers for, in
consequence of the excess of material in the side walls, the tendency of the wires
to separate from each other when the air tube is inflated, is sometimes counteracted
or reversed, the tendency being rather for the wires to draw together. In such
cases the wired edges of the cover may engage with grooves located outside
the edges of the wheel rim especially if restraining material is used in the
air tube.
In the alternative form of the tyre shown in Figures 5 to 9 (inclusive) each of
the corrugations A' A² A' A' extends over a greater length of the complete
circumference than the individual corrugations in the preceding example and
moreover they are considerably deeper, the tread-projections A' extending con-
siderably to the outside of the edge wires Bas shown particularly in Figure 9 and
the tread recesses A² extending inwards as close as practicable to the wires Bas
shown particularly in Figure 6. At the parts corresponding with the tread
recesses A the sides of the tyre overlap the wires B and the main portion of the
tyre's substance is located at the inside of the wires B that is to say it is nearer to.
the axis of the complete tyre than is the portion of the tyre corresponding with
each tread-projection A. By referring to Figures 6, 7 8 and 9 it will be seen that
the tyre A varies in width in substantially the same manner as that shown in

page_text: Figures 1, 2, 3 and 4 the widest parts corresponding with the tread recesses A'
and the narrowest parts with the trend-projections A' and graduating between
these two extremos so that it may be pointed out that, like said previons example
the one last described is formed with side corrugations as well as tread-corrugations.
I am aware that tyres have been made with the inside rubber in compression, by
turning tubes or covers inside out after vulcanizing, but this method puts extra
strain on the fabric and moreover although the inner side of each such tyre is under
compression the outer side, where it is of the utmost importance that it should be
in compression is under tension in which condition it is particularly liable to
puncture.
I am also aware that the inner or nir-tubes of pneumatic tyras have
been corrugated for the purpose of placing the rubber of these tubes under
compression when they are forced by the air pressure against the outer tube or
restraining cover, but this again has the same defect as the previously cited
example, the susceptibility of the outer tube or restraining cover
puncture.
:
to
In my arrangement the whole of the rubber of the tyre cover outside the wheel
rim is more or less under compression when the tyre is inflated.
".
The compression of the rubber renders this form of tyre much more resilient
than tyres of the onlinary construction as the "spring" of the rubber acts in
conjunction with the air pressure instead of in opposition to it as occurs in all tyres
the rubber of which is under tension.
In case of the tyre coming in contact with a small stone or obstruction on the
rond the free or extra material in the tyre allows the latter to absorb the
obstruction thus economizing power. Instead of canvas I prefer to use transverse
fibrous threads to strengthen and limit the expansion of the tyre, and when the
rubber is under compression longitudinal threads are not abs ilutely necessary.
This invention is applicable to either single tube or detachable tyres.
This invention is capable of considerable difications for instance the tyre may
be made with corrugations on the tread surface only, and the corrugations may be
of any desired form other than that shown in the drawings for example, they may
be of circular form and made in various parts of the tyre the object being to
vulcanize the tyre in such a form that its surface area is larger when deflated
than when inflated. 1 do not confine myself to any particular arrangement in
obtaining the last mentioned result but I prefer to so arrange the tyre that the
tread part shall not be drawn or forced to either side either upon deflation or
inflation.
narrow
By the term trend portion herein employed I not only menn a
strip at the centre of the tyre but any portion thereof likely to
come into
contact with the ground or with an article or substance likely to puncture
the tyre.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, i declare that when
I claim is :-
1. A pneumatic tyre which when deflated is corrugated and its tread portion not
in compression and when inflated is less corrugated or not corrugated at all and has
its tread portion in compression substantially as described.
2. A. pneumatic tyre having restraining material to limit its expansion and
so constructed that when deflated it will be corrugated and its tread portion
will not be in compression and when inflated it will be less corrugated or not
corrugated at all and its tread portion will be in compression substantially as
described.
3. A cover for a pneumatic tyre so constructed that when dellated it is corru-
gated and its tread portion is not in compression and when inflated it is less
corrugated or not corrugated at all and its tread portion is in compression and
having a restraining material for limiting its expnusion and inextensible elges
substantially as described.

page_text: 4. A pneumatic tyre which when deflated has its tread portion corrugated and
not in compression and when inflated has its tread portion less corrugated or not
corrugated at all and in compression substantially as described.
5. A pneumatic tyre which when deflated has its sides corrugated and its tread
portion not in compression and when inflated has its sides less corrugated or
not corrugated at all and its tread portion in compression substantially as
described.
6. A pneumatic tyre which when deflated has its tread portion and sides
corrugated and not in compression and when inflated has its tread portion and
sides less corrugated or not corrugated at all and the tread portion in compression
substantially as described.
7. An endless tubular pneumatic tyre restrained or inelastic longitudinally at the
part in contact with the wheel rim and having the parts not in contact with the
wheel rim corrugated so that the act of inflation causes circumferential com-
pression in the substance of the tyre by causing the corrugated parts to straighten
or to become less corrugated substantially as described.
8. A pneumatic tyre consisting of an endless tube of rubber the cross sections of
which though of varying form on different transverse planes making similar angles
with the axis of the tube have all the same or approximately the same circum-
ferential dimension the outer parts of the tyre when the latter is deflated being
corrugated and the inner part where it is attached to the wheel rim being inelastic
and not corrugated substantially as and for the purpose described.
9. A pneumatic tyre which when deflated is corrugated at the outer parts but
not corrugated at the inner part or part attached to the wheel rim the corrugations
being so arranged that the tyre has the same or approximately the same circum-
ferential dimension on different transverse planes making similar angles with the
axis of the tyre substantially as and for the purpose described.
10. A pneumatic tyre having an excess of material at the parts not in contact
with the wheel rim such excess causing the tyre to be puckered or corrugated
when deflated but so arranged that upon inflation the corrugations more or less
disappear owing to the tyre taking its circular or working form substantially as
described.
11. A pneumatic tyre whose tread portion and sides are corrugated and the tread
portion not in compression when the tyre is deflated the projections of the tread
corrugations as regards circumferential position corresponding with the side
recesses and the tread recesses with the side projections and in which when the
tyre is inflated the corrugations partially or wholly disappear and the tread portion
is in compression substantially as described and illustrated in Figures 1 to 4 of the
accompanying drawings.
12. A pneumatic tyre whose sides are corrugated and tread portion not in
compression when the tyre is deflated the projections of the corrugations at one
side as regards circumferential position corresponding with the recesses at the other
side all these corrugations partially or wholly disappearing and the tread portion
being in compression when the tyre is inflated substantially as described and
illustrated in Figure 10 of the accompanying drawings.
13. A pneumatic tyre which when deflated has its sides and tread portion
corrugated and its tread portion not in compression and when inflated has less
corrugation or no corrugations at all and its tread portion in compression the
projections of the corrugations at one side of the tyre as regards circumferential
position corresponding with the recesses of the corrugations at the other side
substantially as described.
14. A cover for a pneumatic tyre which when deflated is corrugated and its
tread portion not in compression and when inflated is less corrugated or not
corrugated at all and its tread portion in compression and in which when in its
deflated condition the main portion of its substance is outside its edges at the pro-
jections of the tread corrugation and inside its edges at the recesses of the tread
'

page_text: corrugations substantially as described and illustrated in Figures 5 to 9 of the
accompanying drawings.
DULCO LES
THOMAS SLOPER.
Boult & Wade,
Agents for the Applicant.
THOMAS SLOPER.
Boult & Wade,
Agents for the Applicant.