Improvements in Pneumatic Tyres.
Year: 1898

page_text: Date of Application, 5th Apr., 1898-Accepted, 6th Aug., 1898
COMPLETE SPECIFICATION.
Improvements in Pneumatic Tyres.
I, GEORGE HENRY CLARK, of 123, Pearl Street, Boston, in the County of Suffolk,
and State of Massachusetts, United States of America, Manufacturer of Shoe Pat-
terns, 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 has for its object to improve and simplify the construction of
pneumatic wheel tyres, and to so construct the same that the tyre when inflated
will be approximately egg-shaped in cross section, with the smaller end at the
tread side of the tyre.
The invention consists in enclosing an inflatable air tube in an expansive sheath,
which latter may be formed of a strip of fabric cut off on the bias and wrapped
around said tube, the long side edges of said expansive strip being connected to-
gether or joined by suitable means, and in providing, at the tread side of said
expansible sheathed air tube a non-extensible circular protecting strip which is
made segmental, or substantially so, in cross section, such a strip preventing expan-
sion of the sheathed air tube at the tread side of the tyre and consequently causing
said tube to expand laterally, thereby producing an egg-shaped tyre: also in pro-
viding at the tread side of said expansive sheathed air tube a non-extensible cir-
cular protecting strip, having as a co-operative part of it a circular strip of cork,
segmental, or substantially so, in cross section; and composed of two or more strips
of cork having scarfed ends, secured together; also in constructing a non-exten-
sible circular protecting strip for pneumatic wheel tyres, composed of two or more
strips of cork having scarfed ends secured together, made segmental, or substan-
tially so, in cross section, and a non-expansive strip of fabric secured to said seg-
mental strip; also in constructing a substantially non-extensible circular protect-
ing strip for the tread side of pneumatic wheel tyres; made segmental or substan-
tially so, in cross section.
In the accompanying drawing.
Figure 1, shows in cross section a pneumatic wheel tire embodying this inven-
tion, said tyre not being inflated..
Figure 2, a similar cross section of the tyre, shown inflated, but with a different
outer covering.
Figure 3 is a cross sectional detail of the non-extensible protecting strip which
I may employ.
Figure 4 is a detail of a portion of a strip of fabric cut off on the bias and form-
ing the expansive sheath or covering for the air tube.
Figure 5 is a detail showing a portion of the non-expansive strip of fabric which
forms a co-operative part of the non-extensible protecting strip at the tread side
of the sheathed air tube.
Figure 6 is a cross sectional detail showing the air tube and its expansive sheath
thereon; and
Figure 7, is a similar cross sectional detail showing a modified form of joint
connecting the edges of the expansive sheath for the air tube.

page_text: Figure 8 is a detail of a portion of the non-extensible protecting strip.
Referring to the drawing a represents the air tube, which is made of rubber
and of a size slightly less in cross section than it is desired it shall assume when
inflated. Such tube may be formed upon a mandril if desired.
b represents a sheath which contains or encloses said air tube. This sheath b is
made expansible so as to expand with the air tube, when the latter is inflated. I
find in practice that such a sheath may be made of fabric by cutting it off on the
bias, as represented in Figure 4, and said strip, instead of being wound spirally
upon the air tube as usual, is laid lengthwise along on said air tube, and wrapped
about it. The longitudinal side edges of the expansive strip bare brought together
as shown in Figure 6, and upon the inside a narrow strip of rubber c is provided
which joins said side edges together. This narrow strip c may be applied, first
to one of the longitudinal edges of the strip b, as shown in Figure 4, and then
the other edge of said strip is brought into juxtaposition to the aforesaid edge
and secured to said narrow strip c.
Outside of said expansive sheath and opposite the strip c, a narrow strip d of
non-expansive fabric is applied, such strip being cut lengthwise the piece instead
of on the bias, and said non-expansive strip d not only assists in connecting the
edges of said strip b, but also prevents said strip from expanding at such point.
The joint thus formed is on the inside or rim side of the tyre, and hence lies upon
or against the rim. or felly of the wheel, and by providing a non-expansive strip
which will prevent the sheath from expanding at such point the tyre is less liable
to become loosened from the rim, and the thereby creep. I prefer such manner of
connecting the edges of the strip 6 more particularly because of the efficiency,
but said edges may be connected by merely overlapping them, as shown in Figure 7.
A non-extensible protecting strip is provided at the tread side of the tyre,
which as herein shown consists of the strips e and f, secured together.
The strip e, which forms a co-operative part of the non-extensible protecting
strip, is preferably composed of cork, yet it may be composed of any equivalent
material, and in Figure 8 the strip e is shown as circular, and composed of four
pieces or strips of cork, segmental in cross section, and formed or provided with
scarfed ends, said strips being firmly secured together to form a continuous circle.
The strip f, which also forms a co-operative part of said non-extensible protect-
ing strip is composed of a non-expansive strip of fabric which is attached to the.
protecting stripe and said strip fis made wider than the said protecting strip e,
to which it is attached, so that its edges may project considerably beyond the edges
of said protecting strip.
The non-expansive strip f may be cut off the piece lengthwise, as represented
in Figure 5.
The strip f, thus produced is segmental in cross-section, serves to protect
the tube a from being easily punctured. is non-extensible and continuous.
The strip ef is placed at the tread side of the sheathed tube, and cemented
thereto and secured in the process of vulcanization.
The tyre thus constructed will present an expansible sheathed tube having
means at the rim and tread sides thereof to prevent it from expanding at such
points, and consequently it will bulge more or less at the sides between said
restrained portions, as shown in Figure 2, and its widest diameter will be brought
below the centre, or nearer the rim than the tread.
The outer face of the cork protecting strip is curved transversely corresponding
to the arc of a circle of substantially the same diameter as the diameter of the
non-inflated air tube, see Figure 1, and when said air tube is inflated, and its sides
bulged outwardly, as above set forth, said projecting strip will project and will
result in producing a tyre approximately egg-shaped in cross section, with the
small end at the tread side of the tyre.
The expansive strip of fabric b, will or may be treated with rubber or with
a rubber compound, and so also may be the non-expansive strip f, and all of the
parts will be vulcanized together.

page_text: It will be seen that the air tube and its sheath and the protecting strip e-f, are
all vulcanized together, independent of the outer covering or jacket.
The continuous circular strip e, made segmental or substantially so in cross sec-
tion, may be used in any form or construction of pneumatic wheel tyre, and so I
do not herein desire to limit my invention to such strip taken in connection with
the other parts.
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:-
1. A pneumatic wheel tyre comprising an inflatable air tube an expansive sheath
of fabric containing it, and a non-extensible circular protecting strip, segmental in
cross section, at the tread side of said sheathed tube, all of said parts being vul-
canized together and producing, when inflated, an egg-shaped tyre, substantially
as described..
2. A pneumatic wheel tyre comprising an inflatable air tube, and a substantially
non-extensible circular protecting strip, segmental or substantially so in cross section,
at the tread side of said tube, composed of one or more pieces joined at the ends,
and an outer covering for the tyre, substantially as described.
3. In a pneumatic wheel tyre, an inflatable air tube, an expansive sheath con-
taining it, a non-extensible circular protecting strip at the tread side of said
sheathed tube, comprising essentially a circular strip of cork, segmental in cross-
section, and composed of one or more cork strips scarfed at the ends and secured
together, and an outer covering for the tyre, substantially as described.
4. A pneumatic wheel tyre comprising an inflatable air tube, contained within
an expansive sheath, a non-extensible protecting strip at the tread side of said
sheathed tube, composed of a circular strip of cork, segmental or substantially so
in cross section and a non-extensible strip of fabric secured thereto, all of said
parts being vulcanized together, substantially as described.
5. A pneumatic wheel tyre having as a co-operative part of it a textile strip
vulcanized to the tread side of the air tube, and a circular strip of cork composed
of one or more pieces of cork joined at the ends, placed upon, and secured to said
textile strip at the tread side of the air tube, and vulcanized thereto.
6. A protecting strip for pneumatic wheel tyres consisting of a circular strip
of cork, segmental in cross section, and composed of two or more cork strips scarfed
at the ends and secured together, and a non-expansive strip of fabric secured to
said segmental strip, substantially as described.
7. A protecting strip for pneumatic wheel tyres consisting of a circular strip
of cork, segmental or substantially so in cross section, and composed of one or
more pieces having scarfed ends joined together.
8. A protecting strip for pneumatic wheel tyres consisting of a non-extensible
circular strip, made segmental or substantially so in cross section.
Dated this 5th day of April 1898.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.