Improvements in Pneumatic Wheels.
Year: 1896

page_text: Date of Application, 20th June, 1896
1000
PROVISIONAL SPECIFICATION.
Improvements in Pneumatic Wheels.
I, CHARLES KINGSTON WELCH, of Park House, Coventry, in the County of
Warwick, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to pneumatic wheels chiefly intended for vehicles although
not confined to such use, and has for its object to secure between the axis and the
periphery of the wheel an annular air cushion so constructed that no creeping of
one part of the wheel over the other can take place and so that the wheel can be
used not only for supporting a load but also for driving purposes. My improved
wheel is very suitable for tram-cars, omnibuses auto-cars vans and the like, and
generally for all heavy road vehicles whether drawn by muscular power or pro-
pelled by mechanical means, and whether the tractive or propelling force is
applied directly to the body of the vehicle or is transmitted through the axle or
axles. The enclosing cover of the air chamber is formed by two concentric rigid
rings or cylinders one of larger diameter than the other and two flexible side discs
or rings furnished with cores in their edges or having thickened edges which
answer the same purpose as cores. That is to say, the inner or smaller edge is
rendered by the thickening or by the core practically inextensible and the outer
or larger edge is similarly rendered practically incompressible either alone or
when supported by the rigid ring. The flexible side disc or rings may be made of
woven fabric alone or incorporated with India rubber, or they may be made of a
large number of strong flexible threads crossing each other in any desired or suit-
able manner.
The cores when such are used may consist of endless rings of strong
wire. I prefer to use an inner inflatable India rubber tube to contain the air
under pressure although such a tube may in some instances be dispensed with.
In one construction the concentric rigid rings are each made with a depression
or with two depressions on their faces that oppose each other in order that the
cores of the flexible rings may be placed eccentric to the axis of the wheel when
desired to admit of the removal of the said flexible rings and of the replacement of
them in the rigid-rings. The method of removing the flexible rings from the
inner or smaller rigid ring is substantially the same as that described in the
Specification of Letters Patent No. 14563 of 1890 with reference to Figure 18 of
said specification, and the method of removing the side rings from the outer rigid
ring is analogous to the method described in said specification, only in this case
the cores are removed by drawing them through the inner edge of the ring instead
of over the outer edge. The recesses in the rigid rings may be filled by a suitable
filling material after the flexible side rings are in place so as to maintain the cores
concentric and prevent them from assuming a position whence they would be
liable to become detached. In some instances however the fillings are dispensed
with and the rigid rings are constructed with bearing portions or shoulders for
the edges of the side rings to rest upon, the said edges being moved when in place
away from the recesses and on to the bearing parts or shoulders and being kept

page_text: thereon by the internal air pressure. I sometimes construct the rigid rings with
inwardly inclined flanges similar to those of the rim of a wheel fitted with a
"clincher" tyre. At other times I make the rings with inwardly curved flanges
to hook over the edges of the flexible side rings which are made to fit the said
curved flanges.
I may make the flexible side rings of such shape that they will bulge out very
considerably when inflated so that when the wheel is supporting a very heavy load
the contraction of the side rings at the upper part of the wheel will not be
sufficient to cause any undue stress in the fabric or material composing said
flexible rings or to draw the cores inward to such an extent as would be liable
to result in the disconnection of the parts of the wheel.
In some instances the two side flexible rings may be connected by a transverse
web at their inner or outer edges. The wheel may be made as wide as an ordinary
tram car wheel or it may be extended so as to be as wide as the vehicle in which
case the outer and inner rings become long tubular casings constructed at their
ends to receive the side flexible rings which with the tubular casings form the
enclosing walls of the air chamber. In some instances the inner ring is constituted
by the hub of the wheel or even by the axle; in other instances it is much larger
than the hub and is united to the hub by arms or by a disc. In the case of wheels
for tram-cars for example where it is important to preserve an accurate gauge
between the wheels I may do this by connecting the outer ring of one wheel with
that of the wheel at the other end of the axle by tie-rods or by a tubular con-
nection or similar device. The outer ring in the case of a tramear wheel may be
furnished with a flange to run on the tramrails or it may be fitted with an outer
flanged rim. In the case of a vehicle wheel for running. on the road the outer ring
may run direct on the road or it may be fitted with an outer metal tyre or with
a rim adapted to receive an India rubber or other elastic tyre.
Dated this 20th day of June 1896
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.
I, CHARLES KINGSTON WELCH, of Park House, Coventry, in the County of
Warwick, 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 relates to an improved construction of pneumatic wheels chiefly.
intended for vehicles although not confined to such use, and the said invention has
for its chief object to secure in a novel manner between the hub and the periphery
of the wheel an annular air cushion so constructed and combined with the wheel
that no creeping of one part of the wheel over another part can take place and
so that the wheel can be used not only for supporting a load but also for driving.
purposes. My improved wheel is very suitable for tramcars, omnibuses, vans,
motor driven vehicles and the like, where absence of vibration is desirable, and
generally for all heavy road vehicles whether drawn by muscular power or pro-
pelled by mechanical means, and whether the tractive or propelling force is
applied directly to the body of the vehicle or is transmitted through the axlo or
axles or otherwise. The enclosing cover of the air chamber is formed by two
concentric rigid rings, one of larger diameter than the other, and two flexible side

page_text: rings. The rigid rings have flanges at each side, the flanges of the larger ring
being turned inwardly or towards the axis and those of the smaller ring being
turned outwardly or away from the axis. The flexible side rings are furnished
with cores in their edges or have thickened edges which when engaged with the
rigid rings answer the same purpose as cores, that is to say, the inner or smaller
edge is rendered by the thickening or by the core practically inextensible and the
outer or larger edge is similarly rendered practically incompressible either alone
or when supported by the rigid ring. The said cores which may consist of endless
rings of strong wire are supported laterally by the flanges of the rigid rings against
which they are pressed by the air in the inflated air chamber. The flexible side
rings may be made of layers of woven fabric suitably arranged, or they may be
made of a large number of strong flexible threads crossing each other in any
desired or suitable manner. The outer surfaces of the flexible rings may be
rendered waterproof by India-rubber or by any suitable varnish or other material.
I prefer to use an inner inflatable India rubber tube to contain the air under
pressure although such a tube may in some instances be dispensed with.
Referring to the accompanying drawings which illustrate my invention
Figure is a transverse section of a portion of a wheel furnished with an air
chamber, and with an outer rim in which is inserted a solid India rubber tyre.
Figure 2 is a transverse central section on a smaller scale of the whole of the
said wheel showing the manner of detaching the incompressible cores from the,
outer ring or rim.
Figures 3 and 4 are sections similar to Figure 1 but illustrating modifications
hereinafter described.
Figure 5 is a similar section of a portion of a wheel constructed according to my
invention and adapted to run on a rail.
Figure 6 is a half central longitudinal section and half elevation of a pair of
tramcar wheels connected by a tube or sleeve in accordance with my invention, and
Figure 7 is a section of one half of a pair of tramcar wheels illustrating a modi-
fication hereinafter described.
Figure 8 is a side view on a smaller scale of one of the annular flexible rings.
Like letters of reference denote corresponding parts in the several figures.
A is the hub of the wheel; B, B3 are the spokes or web as the case may be; C is
the annular air cushion comprising in the preferred form an inner inflatable
tube D enclosed between flexible side rings E, E, an inner rigid ring F and an
outer rigid ring G concentric with the ring F. The rings F and G are formed
with side flanges f, g respectively the former being turned outwardly and the latter
inwardly as shown. The ring G in the case of a vehicle wheel may be constructed
to form the tyre to run direct on the road or rail or it may be fitted with a solid
rubber tread as hereinafter described.
Referring to Figure 1, the rigid ring Fis formed with a central annular groove f',
and with shoulders f, and the ring G is formed with a similar central annular
groove and shoulders g². The shoulders f, g2 serve to maintain the cores c, e¹
of the flexible rings E, E concentric with their respective ring F, G. The said
flexible rings are made from woven fabric or from a number of crossed threads
held together as hereinafter described. The endless wire cores e, care secured
in the edges of the rings E, E in any suitable manner, for example by turning the
edges of the fabric over the wires and stitching and solutioning the edges. The
endless wire rings have such diameters that they will just lie within the rigid
rings and upon the bearing shoulders f, g of said rings. When the air chamber
is inflated by a pump applied to a valve in the manner adopted for inflating
pneumatic tyres, the flexible side rings E, E bulge outwardly as indicated in the
drawing, and put the inner cores e in tension and the outer cores e in compression,
and the said cores in combination with the flanges f, g keep the flexible rings in
position and prevent them from being blown out by the air pressure. The bulging
of the flexible rings is very considerable so that when the vehicle is supporting a
heavy load the contraction of the said rings at the upper part of the wheel due to

page_text: such load is not sufficient to produce any undue stress in the fabric or material
or to draw the cores inward to such an extent as would be liable to result in the
disconnection of the parts of the wheel. It will be obvious that the pressure of
the air keeps the cores upon the shoulders f, g² and prevents them from sliding
into the grooves f', g. The flexible side rings together with the concentric rigid
rings form an inextensible casing for the inner inflatable tube. The flexible rings
can be removed when desired by first deflating the inner tube and then pushing
one of the rings or cores el inward so that one portion of it rests in the bottom of
the central groove g¹ in which position the said core is eccentric to the flanges g
and one side of the core opposite to that which is in the bottom of the central
groove can be withdrawn from under the inner edge of the flange g as indicated in
Figure 2 whereupon the whole of the core will follow. The core e¹ of the other
flexible ring is removed in a similar manner. The inextensible cores e e at the
inner edges of the flexible rings are removed by placing them at one side in the
bottom of the groove so as to allow of the other side being lifted over the flange
in the manner now so well known in connection with pneumatic tyres furnished
with inextensible cores in the inner edges of the covers for securing them to the
rims. The presence of the cores e, e prevents creeping of the flexible rings in
their respective rigid rings.
The outer ring G is constructed to receive a solid India rubber tyre H of
ordinary construction; or any other suitable tyre may be applied to this ring. In
Figure 2 I have shown a thick solid tyre, and in Figure 1 I have shewn a thin tyre
in full lines and a thick one in broken lines.
It is obvious that the air cushion above described may be constructed to occupy
any position between the hub and the periphery of the wheel, or in small wheels
it may even take up the whole of the space usually occupied by the spokes.
The rims F and G shown in Figure 3 are furnished with two side grooves f³ g³
in lieu of the single central groove shown in Figure 1 and when the flexible rings
are in position the said grooves are filled with a suitable filling J, J to support the
cores in a position concentric with the edges of the flanges f, g and so prevent them
from assuming a position in which they would be liable to become detached from
the rigid rings. The filling material is withdrawn wholly or partially when it is
desired to remove the flexible rings. In this figure the outer ring or rim G is
shown having a flat exterior surfaces forming a tyre for running on a road. The
said ring may if desired be fitted with another external metal or other tyre.
In Figure 4 I have shown a modification wherein the rings F, G are furnished
with inwardly turned flanges forming circumferential hooks f, g, and the
edges e, el of the flexible rings E, E are formed by closely packed coils of cord for
example or other suitable material that is sufficiently rigid. The said edges are
shaped to fit the hooks f and g and when engaged with the said hooks they are
firmly supported thereby, and the cores el are prevented from collapsing while
the cores e are prevented from expanding when subjected to the air pressure in the
tube D. The cores are maintained in engagement with the hooks f and g by
the air pressure within the tube D. In lieu of the continuous circumferential
hooks on the outer ring above described I may use metal hooks at intervals for
supporting the cores, e. Upan the deflation of the inner tube it is obvious that
the cores in the outer ring can be detached from the hooks f, g'. The solid
rubber tyre H may be secured to the rim G by being vulcanised thereon during the
process of manufacture.
In Figure 5 I have shown a further modification resembling Figure 1 except
that the outer ring or rim G is constructed with a flange G¹ to run in the groove of
a rail. This form of wheel is suitable for a tramcar.
Figure 6 shows a pair of tramear wheels each constructed with an air cushion
according to my invention and having the outer rigid rings G connected by a
tube or sleeve K so as to preserve an accurate gauge or distance between the
flanges G of the wheels. The said sleeve surrounds the axle L, and is formed with
flanged ends L¹ that connect the sleeve to the rings G. The annular

page_text: space between the sleeve K and the axle is sufficient to allow of the
required amount of movement or vibration of the outer rings G relatively to the
inner rings F. In case of deflation of the air tube whether accidental or otherwise
the axle will rest against the sleeve K and prevent injury to the flexible rings E, E
and tube D. The tube K may be cast in one with the rings G as shewn, or the
rings G and sleeve-K with its flange may be built up from separate parts secured
together. Tie rods may be substituted for the sleeve."
It will be obvious that the rings F and G are not limited in width and they may
be as wide as the vehicle in which case the said rigid rings become long tubular
casings constructed at their ends to receive the flexible rings which with the
tubular casings form the enclosing walls of the air chamber.
I sometimes connect the opposite flexible rings by a transverse web or diaphragm
at their inner or outer edges, for the purpose of protecting the inner inflatable tube.
In Figure 7 I have shown a modification in which the air cushion is placed
close to the hub of the wheel instead of close to the rim as in Figure 6. In this
case the hub itself forms the inner rigid ring. The outer rigid rings G of the
two wheels mounted on the same axle are connected by tie rods M of which there
may be three or more to preserve the gauge. I have shown one of the wheels
constructed with removable flanges p, p which are taken off when it is desired to
remove or replace the flexible side rings. In this case central grooves to allow of
placing the cores eccentric to the axis are not necessary.
In Figure 8 I have shown a suitable form of material for making the flexible
rings. It consists of a layer of strong threads m arranged in a ring as shown,
and inclined at a uniform angle to the radii extending from their inner
ends, and crossed by another layer of similar threads inclined in
the opposite direction, the whole being united by India rubber solution
and if desired strengthened by additional layers of threads similarly
arranged. The edges of the fabric so formed are turned over the wire cores e, el
and secured by stitching or otherwise. One or both sides of the flexible ring so
formed is or are protected by a layer of India-rubber, or by other suitable material
or the rubber may be dispensed with and the fabric is then coated with a suitable
waterproof varnish. In some cases I form the flexible rings of layers of woven
fabric having a warp or weft, and in such case I arrange the layers so that the
direction of the threads in one layer is different from that in another layer, where-
by a uniformly strong fabric is produced.
It will be obvious that my improved wheel is not only adapted for use on heavy
road vehicles but it is also adapted to serve as a driving pulley, in which case the
outer ring G is formed with a flat or curved smooth outer periphery like an
ordinary belt pulley; or the improved air cushion above described may be used
in any wheel where it is desirable to reduce vibration.
Although I prefer to use endless wire cores as above described it is obvious that
wire rings not endless may be used, the ends of said rings being connected together
by any mechanical device or brought through a hole or holes in the outer rigid
ring and secured by a nut or otherwise.
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. In a wheel, an annular pneumatic cushion formed by an air chamber
enclosed between two rigid flanged concentric rings, and two flexible side rings,
the inner edges of the latter being inextensible and the outer edges incompressible
and said edges being enclosed by the flanges of the rigid rings, substantially as
described.
2. The combination, with the flexible side rings, of the outer rigid flanged
ring constructed with a shoulder or shoulders forming a seat or seats for the incom-
pressible edges of the flexible rings, and a groove or grooves to permit of the said
incompressible edges being placed eccentric to the flanges of the outer rigid ring

page_text: to allow of the withdrawal of the said incompressible edges through the inturned
flanges of the rigid ring, substantially as described.
3. The flexible side rings each having an incompressible core in its outer edge
and an inextensible core in its inner edge, substantially as, and for the purposes,
specified.
4. The flexible rings each constructed of two or more series of closely packed
threads, arranged to cross each other at an angle and having wire or equivalent
cores in its edges, substantially as described.
5. The modification of my invention wherein the outer edges of the flexible
side rings are reinforced by cords or an equivalent thereof shaped to form circum-
ferential hooks, and the outer rigid ring is formed with corresponding inwardly
turned edges or circumferential hooks to engage with the edges of the flexible
rings, substantially as, and for the purposes, specified.
6. The combination, with the grooved outer rigid ring, of a filling for the grooves
to keep the incompressible cores of the flexible rings concentric with the flanges of
the rigid ring, substantially as described.
7. The combination, with a pair of tramcar wheels each having an annular
pneumatic cushion between the hub and the rim, of a tubular or other rigid con-
nection between the outer rigid rings or rims to maintain a constant gauge, sub-
stantially as described.
8. A. wheel constructed with an annular pneumatic cushion between the hub
and the rim, substantially as described with reference to Figures 1 and 2, or to
Figure 3, or to Figure 4, or to Figure 5, or to Figure 6, or to Figure 7 of the
accompanying drawings, for the purposes specified.
Dated this 20th day of April 1897.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.