Improvements in and connected with Pneumatic Tyres.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Pneumatic Tyres.
I, GEORG BRUCK, of 43, Michaelkirchstrasse, Berlin, in the German Empire,
Chemist, do hereby declare the nature of this invention to be as follows:-
This invention consists in an improved manufacture or construction of a pneu-
matic tyre for cycles and other road vehicles having for its object to keep the
tyre serviceable although punctured in one or more places.
For this purpose the tyre is composed of a series of hollow indiarubber chambers,
which may be balls, mounted side by side round the circumference of the rim,
which are inflated by introducing compressed air into them from a main conduit
or pipe through back pressure valves, so that if a chamber or ball, or several of
them should become injured and collapse, the rest remain inflated and the tyre
remains serviceable.
For the purpose of inflating the chambers or balls an annular tube of steel or
other suitable material is placed round the rim, which is preferably made concave
or crescent shaped. On this tube there are fixed as many nozzles as there are
hollow indiarubber chambers or balls, and each fitted with a non-return valve of
any suitable kind. Preferably I make the nozzles slightly tapering and closed
at the ends with a lateral outlet or more than one, and push over them a sleeve
of soft indiarubber which forms the valve. The several chambers or balls are con-
nected air tight to the nozzles, for which purpose they may be formed with necks
fitting over the nozzles and clamped thereto.
The annular tube has a branch, or several branches, passing through the rim
and arranged for the attachment of the inflator and fitted with non-return valves.
By forcing air into the tube the several chambers or balls are filled with com-
pressed air, the valves closing when the inflation ceases and keeping the chambers
filled with compressed air.
If one or several of the chambers or balls is or are punctured, air will only escape
out of these and the annular tube, while the remaining chambers or balls continue
inflated and the expansion of those adjacent to a punctured one will compress it
and more or less fill up the space.
The non-return valve in the branch for inflating the annular tube may be
omitted, but is preferably used, as it keeps the nozzle valves relieved from pressure
till a puncture occurs.
When balls are used as expansible chambers, they are placed close to each other,
so that when inflated their sides become flattened, and they assume an elliptical

page_text: form, and when one of them bursts, the gap is filled out by the expansion of the
adjacent balls to their spherical form.
The balls chambers may be covered by an arch shaped tyre jacket made and
fixed to the rim in any of the usual ways.
T
1007
1
R. J. URQUHART,
Harrington Chambers, Liverpool,
57, Barton Arcade, Manchester,
Consulting Engineer & Patent Agent.
Improvements in and connected with Pneumatic Tyres,
I, GEORG BRUCK, of 43, Michaelkirchstrasse, Berlin, in the German Empire,
Chemist, 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 in an improved manufacture or construction of pneumatic
tyres for cycles and other road vehicles having for its object to keep the tyre
serviceable although punctured in one or more places.
For this purpose the tyre is composed of a series of hollow indiarubber chambers,
which preferably are balls, mounted side by side round the circumference of the
rim, which are inflated by introducing compressed air into them from a main
conduit or pipe through back pressure valves, so that if a chamber or ball,
or several of them, should become injured and collapse, the rest remain
inflated and the tyre remains serviceable. The balls or chambers may be covered
with an arch shaped tyre jacket made and fixed to the rim in any suitable usual
way.
On the drawing appended hereunto
.
Figure 1 shows an elevation of a bicycle rim fitted with the improved tyre;
Figure 2 a vertical section through the rim, on an enlarged scale, and
Figure 3 a cross section on a further enlarged scale.
In the bottom of the felloe or rim A, which is preferably concave as shewn,
a circular air conduit or pipe a of steel or other material, is arranged, which is formed
with as many nozzles b as there are hollow indiarubber chambers to be used, which
chambers in the tyre shewn are balls. Each of these nozzles contains a small back
pressure or non-return valve, and on each an indiarubber ball C or other chamber
is fixed air-tight. The valve may be formed of a piece of indiarubber tubing
pushed over the nozzle which in this case is closed at the end and has lateral
perforations covered by the tubing. The ball is fixed on the nozzle preferably by
being formed with a neck which is pushed over the nozzle and piece of tubing and
fixed by a clamping ring or wire band.
The tube a is further provided with a branch c or several of them arranged for
having the usual inflating pump attached to them. When several such branches
are used, each is fitted with a back pressure valve; when only one is used, it may
be so fitted or not.
When the inflator is attached and worked, the steel tube a is filled with com-
pressed air which flows through the nozzles into the indiarubber balls, the non-
return valves opening during the inflation, until all the rubber balls are filled with
compressed air and have attained the desired resiliency.
F "

page_text: When the inflator is removed, the air will escape from the tube a if no back pres-
sure valve is used on the inflating branch, and all the non-return valves on the
nozzles will close self-actingly, so that the balls remain filled with compressed
air while in the steel tube there is atmospheric pressure. If a ball becomes
ruptured or several become ruptured, this will not affect the other balls, as the
non-return valves in them will continue to be kept closed by the air pressure in
the balls. If a back pressure valve is provided in the inflating branch c, the tube a
after removal of the inflator will remain filled with compressed air, which has the
advantage that the pressure on the non-return valves on the nozzle is the same on
both sides and they are equilibrated, and thus less subject to wear. If ball
becomes punctured or ruptured, the air will escape from the tube a, but as this
occurs only seldom and the tyre will not be used for any length of time without
replacing the injured ball by a new one, the arrangement of a back pressure valve
in the branch c will be advantageous.
a
Preferably the balls are arranged so closely together and are of such size, that
when inflated their sides in contact are flattened against each other and the balls
assume an elliptical or similar form, which changes into a spherical form on one
side, when a ball collapses as represented on Figure 2. If the size of the balls
or the shape of the chambers is such that the two adjacent extended balls or
chambers touch each other they largely remedy the defect which would arise if
there were an empty space between two balls, and there will be no inconvenience
to the rider if he continues the use of the tyre after the collapse of a ball.
As stated herein before, the balls may be covered by an arch shaped jacket fixed
on the felloe in amy suitable usual manner.
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:-
-
The construction or formation of a tyre for bicycles and other road vehicles of
hollow indiarubber chambers or balls each of which is connected airtight to a
nozzle formed or fixed on an air tube in the cavity of the felloe and provided
with a non-return valve, with or without an arch shaped tyre jacket, substantially
as hereinbefore described and illustrated by the drawings.
1111
And 1000
R. J. URQUHART,
57, Barton Arcade, Manchester,
Harrington Chambers, 24, North John Street, Liverpool,
Consulting Engineer & Patent Agent.