Improvements in and relating to Pneumatic Tyres.
Year: 1893

page_text: Date of Application, 26th Oct., 1893
Complete Specification Left, 26th July, 1894--Accepted, 1st Sept., 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to Pneumatic Tyres.
I, CAMILLE JOSEPH VICTOR LEOPOLD JENATZY, of Avenue de la Reine,
Brussels, in the Kingdom of Belgium, Engineer, do hereby declare the nature
of this invention to be as follows:-
:-
This invention consists of improvements in and relating to pneumatic tyres for
the wheels of cycles and other vehicles; its primary object being to enable the
tyre to be quickly detached from or reattached to the rim of the wheel.
A tyre constructed according to this invention is mounted in a metal rim made
with a low vertical flange on each side. The cover or envelope is of india-rubber
and canvas or other fabric, and has along each edge an upright band, preferably
almost rectangular or trapezoidal in cross section, and made of hard but not brittle
india-rubber, which is adapted to give a comparatively good resistance to pressure.
In those parts of the hard india-rubber bands having the greatest diameter, endless
rings of wire or other inextendible material are embedded. The internal diameter
of these endless rings must be greater than that of the external diameter of the
flanges of the rim by at least the thickness of one of the upright bands in order
to permit of the attachment and detachment of the cover. The air-tube used is of
pure india-rubber.
After placing the air-tube in the cover, the band at the edge of the cover is
made to lie at right-angles to its normal position. This enables the band to be
passed over the flange of the rim, whereupon the former assumes a nearly upright
position, the part containing the endless ring being slightly inclined toward the
centre of the rim. The inclination of the band is caused by the fact that the
diameter of that part of the rim on which the band rests is somewhat greater than
the internal diameter of the band, the external diameter of the band being constant
owing to the endless ring embedded in the band. On the inflation of the tyre,
those parts of the bands containing the endless rings are forced outwards until the
bands assume their normal position, the endless rings, owing to their being
inextendible, causing the lower parts of the bands to exert great pressure on the
bottom of the rim. The internal pressure of the air in the air-tube also forces
the bands laterally against the flanges of the rim, the tyre thus becoming safely
fixed.
There should be such a relation between the height of the bands on the edges
of the cover and the height of the flanges on the rim that inflation of the tyre
tends to bring the endless rings toward one another. If the bands be too bigh or
the flanges too low, inflation of the tyre would automatically detach the cover.
After the air has been let out of the air-tube, the cover can be detached by
pulling each side of the cover in turn until the bands lie at right-angles to their
normal position, when they can be drawn over the flanges of the rim, thus giving
ready access to the air-tube.
Dated the 26th day of October 1893.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Chartered Patent Agent.

page_text: Improvements in and relating to Pneumatic Tyres.
I, CAMILLE JOSEPH VICTOR LEOPOLD JENATZY, of Avenue de la Reine,
Brussels, in the Kingdom of Belgium, 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 :-
This invention consists of improvements in and relating to pneumatic tyres for
the wheels of cycles and other vehicles; its primary object being to enable the
tyre to be quickly detached from or reattached to the rim of the wheel.
In the accompanying drawings,
Fig. 1 is a cross section of a pneumatic tyre and rim constructed according to
the present invention; the air-tube being deflated and the cover partly attached.
Fig. 2 is a similar view showing the cover attached to the rim and the air-tube
deflated.
In Fig. 3, the air-tube is inflated.
In Fig. 4, the air-tube is deflated and the cover partly detached.
Figs. 5 and 6 illustrate a slight variation in construction.
Figs. 7 and 8 represent a cover having edges of modified shape.
A tyre constructed according to this invention is mounted in a metal rim made
with a low vertical flange on each side. The cover or envelope is of india-rubber
and canvas or other fabric, and has along each edge an upright band A, preferably
almost rectangular or trapezoidal in cross section, and made of hard but not brittle
india-rubber, which is adapted to give a comparatively good resistance to pressure.
In those parts of the hard india-rubber bands having the greatest diameter, endless
rings a of wire or other inextendible material are embedded. The internal diameter
of these endless rings must be greater than that of the external diameter of the
flanges of the rim B in order to permit of the attachment and detachment of the
cover. The air-tube c is of pure india-rubber.
After placing the air-tube c in the cover D, the band A at one of the edges of
the cover is made to lie at right-angles to its normal position, as indicated on the
left-hand side of Fig. 1. This enables the band A and ring a to be passed over
the flange of the rim B, whereupon the band assumes a nearly upright position
as shown on the right-hand side of Fig. 1; the part containing the endless ring a
being slightly inclined toward the centre of the rim. In Fig. 5, the bands are at a
greater inclination.
The inclination of the band A is caused by the fact that the
diameter of that part of the rim B on which the band rests is somewhat greater
than the internal diameter of the band; the external diameter of the band being
constant owing to the endless ring a embedded in the band. On the inflation of
the tyre, those parts of the bands A containing the endless rings a are forced
outwards until the bands assume their normal position, as represented in Fig. 3;
the endless rings a, owing to their being inextendible, causing the lower parts of
the bands A to exert great pressure on the bottom of the rim B. The internal
pressure of the air in the air-tube c also forces the bands A laterally against the
Hanges 6 of the rim B; the tyre thus becoming safely fixed.
There should be such a relation between the height of the bands A on the edges
of the cover D and the height of the flanges 6 on the rim B that inflation of the
tyre tends to bring the endless rings a toward one another. If the bands be too
high or the flanges too low, inflation of the tyre would automatically detach the
cover.
After the air has been let out of the air-tube c, the cover D can be detached by
pulling each side of the cover, as indicated on the right-hand portion of Fig. 4,
until the bands A lie at right-angles to their normal position, when they can be
drawn over the flanges b of the rim B, thus giving ready access to the air-tube c.

page_text: In many instances, it will, however, be sufficient to draw only one of the bands A
off the rim B.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim :—
1. A pneumatic tyre for the wheels of cycles and other vehicles constructed and
arranged substantially as described with reference to the accompanying drawings,
the same comprising a cover furnished at the edges with bands of hardened india-
rubber and endless rings larger in diameter than the flanges of the rim.
2. A pneumatic tyre for the wheels of cycles and other vehicles substantially as
herein described, the same comprising a cover, such as D, of india-rubber and
restraining material having at the edges bands, such as A, made of hardened india-
rubber, and furnished with endless inextendible rings a, the internal diameter of
the rings a exceeding the external diameter of the flanges of the rim.
3. In a pneumatic tyre for the wheels of cycles and other vebicles, the combina-
tion, with the cover D provided with bands A of hardened india-rubber and endless
rings a, of the rim B having flanges 6 of less diameter than the endless rings, that
part of the rim on which the bands A rest being of greater diameter than the
internal diameter of those bands, substantially as and for the purpose herein set.
forth.
For the App
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Chartered Patent Agent.