Improvements in Pneumatic Tyres.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Pneumatic Tyres.
I; WALTER ROWBOTHAM, of Belvedere, Victoria Road, Twickenham, in the
County of Middlesex, Engineer, do hereby declare the nature of this invention
to be as follows:-
My invention relates to pneumatic tyres in which an internal tube and separate
cover are used but it is also applicable to tubeless tyres.
My object is to produce a secure method of fastening the tyre to the rim which
shall at the same time allow of ready detachability when necessary.
In carrying my invention into effect I form pockets in the edges of the cover'
or the edges of the tubeless tyre and within these pockets I place, spiral springs
which springs are quite extensible and permit the cover edges to be freely extended.
I make the edges so extensible that each edge is passed over the maximum circum-
ference of the rim without difficulty. The spiral' spring then causes the edge to
contract and it passes to the bottom of the concave rim when a concave rim is
used. The second edge with its spring is then passed in also but it is expanded,
to pass over the first edge and then it contracts and remains in contact with the
canvas or rubber forming part of the cover joining the other edge. When the tyre
is inflated, either in the tubeless manner or by using an internal tube, the
edges which are of some considerable diameter relatively are forced against each
other and interlock. By this device I am enabled to produce a pneumatic tyre
or a pneumatic tyre cover which securely holds by an interlocking of the edges
which edges are quite extensible and easily placed on or removed from a metal
rim.
In the above described method of carrying my invention into effect any concave
rim will suffice. In another modification which I will now describe a special
rim. is necessary. This rim consists of a concave rim having at the bottom a
V-shaped groove narrow at the mouth and wide below. To utilise this arrange+
ment I first introduce one edge of my spiral spring edge cover or tyre and the
contraction of the spring carries it to the bottom of the rim.
This leaves room for,
the passage of the other edge and when the tyre is blown up both beads are pulled"
up to the narrow orifice or slit and are there jambed against each other and
against the wedge slides.
When I use my invention for the purpose of a tubeless tyre I sometimes
arrange a flap passing from one edge to the other to seal the tyre.
Instead of a spiral spring in the edge I may use an elastic cord such as rubber
or other elastic material which forms a thickish-bead edge and at the same time.
allows of expansion and contraction.
Dated 09.1 day of Tann 1907

page_text: Improvements in Pneumatio Tyres.
I, WALTER ROWBOTHAM, Belvedere, Victoria Road, Twickenham, in the
County of Middlesex, Engineer, 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-
My invention relates to pneumatic tyres in which an internal tube and separate
cover are used but it is also applicable to tubeless tyres.
My object is to produce a secure method of fastening the tyre to the rim which
shall at the same. time allow of ready detachability when necessary.
Referring to the accompanying sheet of drawings; Figure..1, is a sectional
elovation of one form of my tyre, placed on a concave rim.
Figure 2, is a sectional elevation of another form of my tyre placed on a
V grooved rim.
'
special
Figure 3, is a sectional elevation of a tubeless form of my tyre placed on a special
V grooved rim.
In carrying my invention into effect I form pockets A' in the edges of the
cover A, or the edges of the tubeless tyre A2 and within these pockets I place
spiral springs B or india-rubber cords which are quite extensible and permit the
cover edges to be freely extended. I make the edges so extensible.that each edge
i passed over the maximum circumference of the rim C without difficulty. The
spiral spring, B-then causes the edge to contract and it passes to the bottom of the
concave rim C when a concave rim is used. The second edge with its spring ]}
is then passed in also but it is expanded to pass over the first edge and then it
contracts and remains in contact with the canvas or rubber forming part of tho
cover joining the other edge as shewn in Figure 1. When the tyre is inflated,
either in the tubeless manner or by using an internal tube, the pocket edges A',
which are of some considerable diameter relatively, are forced against each other
and interlock. By this device I am enabled to produce a pneumatic tyre or a
pneumatic tyre cover which securely holds by an interlocking of the edges which
edges are quite extensible and easily placed on or removed from a metal rim. Dis
the inner tube, but a tubeless tyre may be made by omitting the inner tube and if
necessary adding a flap similar to that shewn in Figure 3.
In the above described method of carrying my invention into effect any concave
riin will suffice. In another modification, which I will now describe, a special
rim is necessary as shewn in Figures 2, and 3. This rim consists of a concave
rim C having at the bottom a V-shaped groove narrow at the mouth and wide
below. To utilise this arrangement I first introduce one edge of my spiral spring
edge cover or tyre A and the contraction of the spring carries it to the bottom of
the rim. This leaves room for the passage of the other edge and when the tyre
is blown up both beads are pulled up to the narrow orifice or slit and are there
jambed against each other and against the wedge sides.
When I use my invention for the purpose of a tubeless tyre I sometimes arrange
a flap passing, from one edge to the other to seal the tyre. One form of this is
shewn at Fin Figure 3.
24
Instead of a spiral spring in the edge I may use an elastic, cord such as rubber
or other elastic material which forms a thickish bead edge and at the same time
allows of expansion and contraction.

page_text: 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 tyre having a cover such as A with freely extensible edges to
interlock when the tyre is inflated substantially as described with reference to
Figure 1.
2-A pneumatic tyre having a cover such as A with freely extensible edges
adapted to engage in a V-grooved rim substantially as described with referenco
to Figure 2.
:
3, A tubeless pneumatic tyre such as A having freely extensible edges adapted
to interlock, substantially as described with reference to Figure 1.
4, A tubeless pneumatic tyre such as A having freely extensible edges adapted
to engage in a V-groove rim substantially as described with reference to Figure 3.
1000
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.