Improvements in Tyres for Velocipedes and other Road Vehicles.
Year: 1897

page_text: COMPLETE SPECIFICATION.
Improvements in Tyres for Velocipedes and other Road Vehicles.
We, ELIAB Box, of 289, Broadway, Bexley Heath, in the County of Kent,
Architect and Surveyor, and ANDREW PRINGLE, of Cromwell House, Bexley Heath,
aforesaid, Gentleman, 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:-
Our invention has for its object the construction of tyres for vehicles, and the
application of tyres to wheel rims without the use of wires, hooks, overlaps, glue,
cement or other adhesive substance or other device at present or heretofore in use
for fixing tyres to rims, and also the improvement of tyres generally.
Essentially our device consists in forming on or applying to the tyre proper
on that part of its inner periphery which is nearest the rim a separate flexible and
expansible air-chamber extending the whole length of the inner side of the tyre
proper: this air-chamber lies in the hollow of the wheel rim and is inflated through
a valve belonging to itself, or in other ways to be described later. When this
chamber is deflated, the whole tyre including the air-chamber slips over the edge
of the rim in the ordinary way, but when the chamber is swollen by inflation the
tyre can no longer be removed from the rim by reason of the internal pressure forcing
the flexible sides of the air-chamber outwards against the rim and by reason of the
diminution of the inner periphery of the air-chamber. When the air-chamber
is used to fix a solid tyre to a wheel rim the chamber may be fixed to the solid
tyre or it may be made as a part of or as an addition to the solid tyre in manu-
facture and in any of these cases it will obviate a defect of solid tyres, namely want
of resilience or elasticity. The inner circumference of the solid tyre being attached
strongly to the wall of the air-chamber will act as a bridge or stay or tie by hold-
ing the two sides of the air-chamber in their original position and preventing them
from bulging to one side or other as the vehicle takes a turn at an angle to its
former course and so preventing the entire compound tyre from rolling over on one
side or other of the rim. When the air-chamber is to be used with a hollow or
pneumatic tyre the chamber may be formed in manufacture by placing a septum
of flexible and expansible or inexpansible material inside the tube and across its
lumen or bore in a suitable position, or it may be made as an external addition to
an ordinary single penumatic tyre tube. In this case the tendency of the hollow
tyre to roll over the sides of the rim as when the vehicle turns at an angle to its
former course is counteracted by the septum which being arched acts as a bridge,
stay or tie by keeping the two sides of the tyre in their normal position in relation
to each other, and this restraining force will be in proportion to the strength of the
septum and the air pressure in the chamber. With the solid tyre proper the air-
chamber will be provided with a valve and will be inflated as usual. With a hollow
or pneumatic tyre proper the two hollow chambers, namely the tyre proper and the
air-chamber, may each be provided with a valve and may be inflated or deflated
independently of each other in the usual way. In this case the tube for inflating
the tyre proper would be carried through the air-chamber and through the septum

page_text: or the wall of the pneumatic tyre as the case might be, and the air-chamber would
have its own separate valve. But in order to obviate the trouble of two acts of
inflation, and to procure other advantages in pneumatic tyres made with the air-
chamber as above described we place on or in the septum dividing the air-chamber
from the tyre proper a flap or flat one-way valve or any other suitable kind of
valve of which several are well known and used in the arts, and we thus establish a
communication between the tyre proper and the air-chamber, so that air can pass
from the tyre to the air-chamber but not in the opposite direction. Thus when the
tyre proper is inflated, the air-chamber will also be inflated, but should the tyre proper
be deflated the air-chamber will remain inflated, and the tyre as a whole will remain
attached to the rim. In order that the air-chamber may be deflated when so desired
we may fit to it a simple or valved outlet protected in any suitable way. In case
it should be necessary or advisable during inflation to admit air directly to the air-
chamber, we place in the inflation tube for the tyre proper where it traverses
the air-chamber a hole protected by a one-way valve, so that the air shall enter
both the tyre proper and the air-chamber simultaneously, and both tyre proper
and air-chamber will be protected from deflation each by its own valve or valves.
This device may be used in place of the flap or flat valve on or in the septum as
above described. In practice our device is used as follows: The tyre proper solid
or hollow is slipped over the rim in the usual way, then in the case of a solid tyre
the air-chamber is inflated and nothing further requires to be done, but with a
pneumatic tyre the two hollow tubes viz. the tyre and the air-chamber require to
be inflated either separately, the air-chamber first and the tyre next, or together
at one operation as above described. The orifice or orifices of the valve or valves
will be brought through the wheel rim in the usual way. Our compound tyre with
one way valve in the septum or in the inflating tube will accommodate itself more or
less to the weight acting on the tyre, for instance with a heavy
weight on the vehicle the air chamber will be tighter and the tyre
proper less tight than with a light weight on the vehicle. When the vehicle
turns a corner, the adhesion of the air-chamber and so of the whole tyre will be
increased as the condition demands.
In the accompanying drawings we have illustrated our invention by way of
example.
Fig. 1 is a transverse section through a penumatic tyre, and shows the valved
communication between the tyre proper and the air-chamber.
Fig. 2 is another transverse section of the same tyre showing the inflating valve.
Fig. 3 is a section of a solid tyre having an inflatable air-chamber applied thereto
in accordance with our invention.
Referring to Figs. 1 and 2, A is the tyre proper, B is the septum, and C is the
inflatable air chamber, by which the tyre is held upon the rim D which may be of
wood or metal of any suitable shape. E is the inflating valve the stem of which
is pierced with a small hole at e to let air directly into the air-chamber C. F is
a thin india-rubber tube placed in the valve stem and covering the hole e so as to
prevent the air from returning through the hole e while allowing it to enter the
air chamber. G is an opening in the septum B closed on one side by a flap valve H
which will allow the air to pass from the tyre chamber A into the air-chamber C
but will prevent the return of the air through the opening G.
In Fig. 3 we have shown a solid tyre J furnished with an inflatable air-chamber C
on its inner side to which it is firmly secured. E is a valve by which the air-
chamber is inflated and the tyre thereby secured on the rim.
Our device prevents creeping of the tyre round the rim and consequent nipping
of the valve tube by the rim.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. The method of applying to tyres separate flexible and expansible air-chambers

page_text: with means for inflating the same, for the purpose of causing the tyres to adhere
to the rims, substantially as herein described.
2. The method of making pneumatic tyres with separate inflatable chambers
integral therewith for the above purpose, substantially as herein described.
3. The method of imparting greater resilience to solid tyres by means of inflatable
air-chambers between the tyres and the wheel rims, substantially as herein
described.
4. In compound pneumatic tyres of the kind herein referred to the establishing
of an air communication between the tyre proper and the air-chamber, and the
controlling of the said communication by means of a one way valve, substantially
as, and for the purposes, specified.
5. The provision of a one-way valve in the tube leading from the inflating pump
as described, to allow of inflating the two chambers directly at one operation, sub-
stantially as described.
100%
GEORGE HARRISON,
35, Therapia Road, Honor Oak, London,
Agent for the Applicants.