Improvements in or relating to Pneumatic Tyres.
Year: 1899

page_text: Improvements in or relating to Pneumatic Tyres.
I, DEWITT HASKIN BOTHWELL, of Toledo, Ohio, U.S.A., Gentleman, do hereby
declare the nature of this invention to be as follows:-
The object of this invention is to provide a pneumatic tyre for cycles and
vehicles, which will comprise a series of compartments which can be simul-
taneously inflated, but which, in case of puncture of one of them, will not become
deflated and the tyre rendered useless until repaired.
A further object is to provide a tyre in which any of the series of parts of
which it is composed can be quickly removed and access be had thereto for quickly
mending it. Moreover, a tyre constructed in accordance with my invention is
cheap to manufacture, and a seriously injured section can be readily replaced by
a new one without purchasing a new tyre.
The rim of a wheel to be fitted with my tyre has, as usual, an annular groove;
but the sides of the groove are flanged inwardly.
Rubber air-receptacles of suitable length, and of approximate U-shape, have
flanges extending at a right angle and outwardly from each of its edges in such
manner as to engage beneath the inwardly extending flanges of the rim when
the air-receptacles are fitted in the rim with their curved parts outwards. Thin
rubber flaps extend inwardly from the flanged edges of the receptacles, and over-
lap on the base of the groove in the rim. The ends of the receptacles are closed
with the exception of a small aperture which coincides with a like aperture in
each adjacent receptacle when fitted end to end around the rim. The apertures
in each receptacle, except that into which the inflating valve enters, are covered,
on the inside, with a thin rubber flap which forms a valve. The inside surface
of the receptacles may be lined with canvas or suitable strengthening material or
substance.
When air is pumped into the receptacle in which the inflating valve is fitted,
it passes to each of the others, expanding them so that the overlapping flaps form
an air-tight joint, the abutting ends also make air-tight joints, the extending
flanges are held firmly beneath the flanges of the rim. The return of air from
any of the receptacles is prevented by the inwardly opening flap valves. In
order to deflate them the receptacle fitted with the inflating valve is first deflated
and removed, and then the flap valve of each successive receptacle is pressed
inwardly by a blunt pointed instrument until the air has escaped.
In an alternative form, the overlapping flaps take the form of flanges which
are kept in place in the rim and in air-tight contact therewith by curved lengths
of wood. or suitably-shaped metal sections, contained within each receptacle, and
drawn tightly down on the inturned flanges of the tyre to clamp them between
the wood sections and rim, by screws passed through the latter loops may extend
from each wooden or metal clamping section, through the rim, and carry small
eccentrics having projecting pins or handles whereby they may be partially

page_text: revolved to impinge upon the underside of the rim and draw the clamping
sections downwards.
Each clamping section is perforated at its ends to correspond with the perfora-
tions in the ends of the rubber receptacles. These perforations may be covered
with the flap-valves aforementioned. It will be understood that in this con-
struction, the inwardly projecting flanges on the rim, and the corresponding out-
wardly projecting flanges on the receptacles are dispensed with
Improvements in or relating to Pneumatic Tyres.
I, DEWITT HASKIN BOTHWELL, of Toledo, Ohio, U.S.A., Gentleman, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
-
This invention relates to pneumatic tyres which are composed of communi-
cating inflatable sections or chambers arranged end to end around the rim of
the wheel and forming a practically continuous tyre.
The object of my invention is the construction of a tyre of this kind in which
the sections are reliably secured to the wheel-rim and tightly forced against
each other at their adjoining ends to prevent all liability of leakage and in which
any one or more of the sections can be readily detached for conveniently repairing
the same in case of puncture or other damage or for substituting a new section
for an unserviceable one.
In the accompanying drawings, Figure 1 is a side elevation of a velocipede
wheel provided with my improved tyre. Fig. 2 is a fragmentary longitudinal
section thereof on an enlarged scale. Fig. 3 is a cross section of the same, taken
through a clamping bolt of one of the followers or clamping blocks. Fig. 4 is
an end view of one of the sections. Fig. 5 is an inner or bottom plan view of a
section. Fig. 6 is a similar view of one of the followers or clamping blocks;
and Figs. 7 and 8 show a modified method of attaching the sections to the wheel
rim.
Like letters of reference indicate like parts in the several figures.
A is the wheel-rim which may be constructed of any suitable material, but
which is preferably made of wood. The rim is provided in its face with a
circumferential groove «, which is preferably flared outward slightly, as shewn in
Fig. 3.
B are the inflatable sections or separate chambers of the sectional tyre, which
are partially seated in the groove of the rim, so as to project outwardly beyond
the same, and which are arranged closely together and extend throughout the
circumference of the rim, so that they form a practically continuous tyre. These
sections are constructed of a suitable flexible or resilient material, preferably
rubber, and are of such length that they properly conform to the size of the
wheel required.
The sections or chambers are elongated or bulb-like in form and are provided
with a contracted base portion B¹ which conforms to the bottom and sides of the
groove in the wheel-rim. The adjoining sections communicate by means of
registering air passages c, formed in the contiguous ends thereof, whereby all
of the sections are inflated upon forcing air into any one of them through an

page_text: ordinary valve-stem d. Each section or chamber is closed at its ends and on all
sides, except on its inner or seating side, where it is provided with an oblong or
longitudinal opening e which is somewhat smaller than the dimensions of the
base section, so as to leave an inwardly extending marginal flange e¹, which rests
against the grooved face of the wheel-rim, as shewn in Figs. 2, 3, and 5.
F represents clamping blocks or followers of wood or other suitable material,
arranged within the sections or chambers B and overlapping or bearing against
the flanges e of the sections so as to confine the same between the blocks and
the face of the rim... Each of these blocks or followers is drawn toward the rim
by radial clamping bolts or screws g passing through holes in the rim and
entering screw-threaded openings formed in the block, as shewn in Figs. 2 and 3,
so that upon tightening these bolts the flange of the section is securely clamped
against the face of the groove wheel-rim, thereby effectually precluding leakage
of air through the open inner side of the section.. In order to form a more
effectual air-seal the groove of the wheel-rim is flared, as hereinbefore described,
and the clamping blocks are correspondingly tapered or wedge shaped in cross:
section, as shewn in Fig. 3, so that the side walls of the section are compressed'
laterally between the block and the sides of the groove. The ends of the sections
are preferably flat and bevelled slightly so that they recede towards the base of
the sections, as, shewn in Fig. 2. By this construction the joints formed by the
abutting ends of the sections converge toward the centre of the wheel, and each
section is wedged between the two adjacent sections upon being drawn to its
seat on the wheel-rim, thus forcing the sections tightly together and producing.
air-tight joints at their ends.
In order to prevent leakage of air from the sections through the bolt-holes in
the wheel-rim, conical washers or packings h of rubber or other suitable material,
are applied to said bolts between their heads and the rim, these washers being
seated in conical sockets or enlargements h¹, formed at the inner ends of the bolt-
holes.
As shewn in Fig. 2 the clamping blocks F are provided in their ends with
oblique, air passages i, which coincide with the passages in the ends of the
sections and open into the sections for placing the various sections in com-
munication with one another.
The flat end portions of the sections preferably do not extend across the full
diameter of the sections, but only from the base to about the centre of the.
sections, and they project slightly beyond the rounded outer portions of the
sections as shewn in Fig. 1 and 2 so as to leave outwardly flaring spaces j between
the ends of adjacent sections, while the sections are in contact with the ground,
they are compressed causing the same to be further elongated and bringing
their ends more closely together. By constructing the ends of the sections as
shewn, any dirt or other obstruction which may enter and be held in the spaces
between the sections by their compression is allowed to fall out of the spaces as
soon as the sections contract to their normal length by leaving the ground. The
clamping blocks F, which are necessarily larger_than_the_openings_in_the_base_
of the sections in order to overlap their retaining flanges e¹, are inserted in the
sections through these openings the elasticity of the sections permitting the
opening to stretch sufficiently for this purpose. The blocks are curved con-
centrically with the wheel-rim and are made of such thickness as to leave an
ample air-space in the sections.
In constructing the tyre the followers .or clamping-blocks are first inserted
in the sections, and the sections are then assembled around the grooved-wheel-
rim, after which the clamping screws are passed through the holes of the
rim and engaged with the openings of the followers and tightened. whereby the
sections, owing to the bevelled surfaces of the same and the wheel rim, are
compressed both at their sides and ends and forced into such close relation with
the rim and with each other as to effectually prevent and leakage of air when
the tyre is inflated.

page_text: In the modified form shewn in Figs. 7 and 8 headed bolts are passed into
their holes in the clamping blocks F before the latter are placed in their
sections B as hereinbefore described. The bolts at their lower ends are formed
as shewn at to receive a cross-pin / of a bifurcated eccentric L. When the
assembled block and section are placed in position the ends of the bolts k pro-
ject from the inner surface of the wheel-rim sufficiently to permit of the
eccentrics L being engaged therewith by means of the cross-pins 7 and the
handle of the eccentric L being raised until it lies coincident with the interior
circumference of the wheel-rim the clamping blocks F and sections B are drawn
by the action of the eccentric L tightly into the tapered groove in the wheel-
rim.
My improved tyre while possessing the resiliency of an ordinary pneumatic
tyre can be repaired more conveniently and quickly than such a tyre. In case
of puncture or other damage to the tyre it is only necessary to detach the par-
ticular section or sections which are damaged by removing the clamping bolts
and then either substitute a new section, which is comparatively inexpensive,
or repair the injured section, the interior of which is easily accessible through
the opening in its base after removing the clamping block. The tyre is restored
to its original condition upon replacing the new or repaired section, and either
of these repairs can be made in a short space of time and without the employment
of skilled labour.
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
.
(1) The combination with a wheel-rim having a longitudinal groove in its
face, of a sectional pneumatic tyre having its sections seated end to end in the
groove of the rim and each having an open inner side provided with an inwardly
extending marginal flange which bears against the bottom of the rim-groove, a
clamping block arranged in each section and bearing against the flange thereof,
and tightening means for drawing said blocks into the rim-groove for clamping
the flanges of the tyre sections against the bottom of the groove, substantially
as and for the purposes set forth and illustrated.
(2) The combination with a wheel-rim having an outwardly flaring groove,
of a pneumatic tyre composed of inflatable sections or chambers arranged end
to end around said rim and having inwardly tapering base portions seated in
the groove of the rim, a wedge shaped clamping block or follower arranged
within each section and bearing against the sides of its bevelled base portion,
and tightening means for drawing said blocks into said groove, substantially as
and for the purposes set forth and illustrated.
(3) The combination with a wheel-rim having a longitudinal groove in its
face, of a sectional pneumatic tyre having its sections seated end to end in the
groove of the rim and each having an open inner side provided with an inwardly
extending marginal flange which bears against the bottom of the rim groove, a
clamping block arranged in each section and bearing against the flange thereof,
and tightening means consisting of headed bolts passed through the clamping
blocks and having their lower ends adapted to receive a cross-pin of a bifurcated
eccentric, the latter being operated by a handle, for drawing said blocks into
the rim-groove to clamp the flanges of the tyre sections against the bottom of the
groove. substantially as and for the purposes set forth and illustrated.
(4) The combination with a wheel-rim of a pneumatic tyre composed of a
series of inflatable sections or chambers arranged end to end around the face of
the wheel-rim and each provided in its ends with air passages which register
with the passages of adjoining sections, and followers or clamping blocks arranged
within said sections and operating to clamp said sections against the wheel-rim
and provided with air-passages which coincide with the air-passages of the
sections and open into the latter, substantially as set forth.

page_text: (5) An inflatable section for an inflatable pneumatic tyre having an open
inner side provided with an inwardly extending marginal flange adapted to be
clamped against the face of a wheel-rim, substantially as and for the purposes
set forth and illustrated.