Improvements in Pneumatic or Air-Tyres.
Year: 1892

page_text: Date of Application, 29th Oct., 1892
Complete Specification Left, 28th July, 1893-Accepted, 2nd Sept., 1893
PROVISIONAL SPECIFICATION.
Improvements in Pneumatic or Air-Tyres.
WILLIAM THOMAS SHAW, Chairman, ISAAC WATTS BOOTHROYD, Managing
Director, and ARTHUR SYDENHAM, Works Manager of the Crypto Cycle Co. Ltd.
all of No. 64 City Road, London E.C. do hereby declare the nature of this
invention to be as follows:-
At
Our invention consists in an improved construction of tyres for use on the wheels
of velocipedes and other like vehicles, whereby important advantages are secured.
The rim of such wheels we preferably make semi-circular in section with the edges
turned over inwards into the form of a circular tube substantially the same as what
is known as the Warwick grip rim. The tyre itself consists of two portions, an
outer casing formed of vulcanized rubber with insertions of canvas, and thickened
at the tread or weight-bearing portion in the ordinary way, as in the Boothroyd
tyre. This outer casing is moulded into the form of an endless band, U shape in
cross section, and considerably thickened at the edges, so that these latter shall be
wedge-shaped and form feet or supports resting upon the internal surface of the
rim, just beneath the tubular projections on the rim-edges before referred to.
the base of the rim, inside, we attach by cement wire or other suitable means an
endless tube of india rubber encircling the rim, circular in cross-section and of a
diameter somewhat greater than the distance between the circular tubes of the rim,
described above. This endless inner tube forms the second portion of the tyre.
When inflated, by means of a tube with valve inserted through the rim, this inner
tube tightly presses the feet of the U shape endless band and the band itself
against the rim and the turned-over edges or tubes of the same, so as to firmly
grasp and hold the outer band in position and at the same time form an air-tight
joint. By this means a chamber is formed between the outside of the inner tube
and the inside of the endless band forming the outer casing. This air-chamber is
situated immediately behind the tread which is separated from the inner tube by
the space of to inch or upwards at the vertex. The inflation of this chamber
with air, compressed to any desired degree, is effected by a tube (with salve)
passing through but not communicating with the inner endless tube. The result is
that we have a tyre consisting of two separate and distinct chambers of compressed
air, separated by a rubber wall only and therefore possessed of a high degree of
resiliency; whilst, in the event of the puncture of the outer casing, the inner tube,
which is remote from injury, remains intact and in this way affording support, to
the outer casing, the wheel is still available for riding purposes. On the other
hand, if it should be desired to effect an instant repair, the air is allowed to escape
from the inner tube, thus releasing the outer casing which can then be plugged,
plastered, or otherwise mended on the inner side, without causing any inequality or
bulging of the bearing surface, or in any way causing injury to the inner air-tube
from rubbing as is the case when the inner tube and the outer covering are in
contact.
We are aware that in the Clincher rim and tyre an inner tube and an outer
casing are employed, and that the latter is grasped and held by being pressed
between the tube and rim, but it will be observed that our invention differs
essentially from the Clincher both as to form and construction and also by the
intervention of an air-chamber between the inner tube and the tread of the outer
casing.
Tinted thin both 1.…….
w 1000
WM. THOS. SHAW.
1. W. BOOTHROYD.
ARTHUR SYDENHAM.

page_text: COMPLETE SPECIFICATION.
Improvements in Pneumatic or Air-Tyres.
We, WILLIAM THOMAS SHAW, Chairman, ISAAC WATTS BOOTHROYD,
Managing Director, and ARTHUR SYDENHAM, Works Manager of the Crypto
Cycle Co. Ltd., all late of No. 64 City Road, London, E.C. and now of No. 29
Clerkenwell Road London do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
We
Our invention consists in an improved construction of tyres for use on the wheels
of velocipedes and other like vehicles, whereby important advantages are secured.
The rim of such wheels we preferably make semi-circular in section with the edges
turned over inwards into the form of a circular tube substantially the same as what
is known as the Warwick grip rim. The tyre itself consists of two portions, au
outer casing formed of vulcanized rubber with insertions of cauvas, and thickened
at the tread or weight bearing portion in the ordinary way, as in the Boothroyd
tyre. This outer casing is moulded into the form of an endless band, U shape in
cross section, and considerably thickened at the edges, so that these latter shall be
wedge-shaped and form feet or supports resting upon the internal surface of the
rim, just beneath the tubular projections on the rim-edges before referred to.
encircle the rim with a tube of vulcanized india rubber (strengthened by a canvas
insertion) of a diameter somewhat greater than the distance between the circular
tubes of the rim, described above. This endless inner tube forms the second portion
of the tyre. When inflated, by means of a tube with valve inserted through the
rim, this inner tube tightly presses the feet of the U shape endless band into the
recesses below the turned over edges or tubes of the rim and also presses the band
itself against these turned over edges or tubes so as to firmly hold the outer band
in position and at the same time form an air-tight joint between it and the rim.
By this means a chamber is formed between the outside of the inner tube and the
inside of the endless band forming the outer casing. This air chamber is situated
immediately behind the tread which is separated from the inner tube by the space
of to inch or upwards at the vertex. The inflation of this chamber with air,
compressed to any desired degree, is effected by a tube (with valve) passing through
but not communicating with the inner endless tube. The result is that we have a
tyre consisting of two separate and distinct chambers of compressed air, separated
by a rubber wall only and therefore possessed of a high degree of resiliency; whilst,
in the event of the puncture of the outer casing, the inner tube, which is remote
from injury, remains intact and in this way affording support to the outer casing,
the wheel is still available for riding purposes. On the other hand, if it should be
desired to effect an instant repair, the air is allowed to escape from the inner tube,
thus releasing the outer casing which can then be plugged, plastered, or otherwise
mended on the inner side, without causing any inequality or bulging of the bearing
surface, or in any way causing injury to the inner air-tube from rubbing as is the
case when the inner tube and the outer covering are in contact.
Figures 1 and 2 are cross sections of a pneumatic or air tyre constructed
according to our invention, the section Figure 1 is taken through the branch tube
by which the tube which surrounds the metal rim is inflated and the other through
the branch tube through which the outer cover is inflated.
Figures 3 and 4 are similar views of a pneumatic or air tyre slightly modified in
form.
A is the metal rim which is made concave as above stated and has each of its
edges turned over inwards into the form of a circular tube A* or might otherwise
be formed with inwardly projecting flanges overlapping a portion of the rim. B is
the outer cover of canvas and vulcanized india rubber with its edges B* adapted to
fit below the flanges A*. C is the tube by which the rim A is surrounded,

page_text: preferably it is attached to the rim by cement or by wire or other suitable means.
Cx is a tube branching off from the tube C and passing through the rim. The end
of this tube would carry a valve in the ordinary way to allow of the tube C being
inflated through it. B** is a similar branch tube carried through the rim and
through the tube C to allow of the outer cover B being inflated.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we would state that we are
aware that in the Clincher rim and tyre au inner tube and an outer casing are
employed, and that the latter is grasped and held by being pressed between the
tube and rim, but it will be observed that our invention differs essentially from the
Clincher both as to form and construction and also by the intervention of an air
chamber between the inner tube and the tread of the outer casing. We are also
aware that attempts have been made to hold the edges of an outer casing of U form
to the metal rim of the wheel by means of an inflated tube separate from the main
inflated tube by which the outer casing is kept distended. What we claim is :-
1. The combination of a concave metal rim having inwardly projecting flanges
along each of its side edges-a flexible outer cover or tyre of U form having its
edges adapted to fit below the flanges of the rim and a tube of less diameter than
the cover surrounding the rim and which can be inflated so as to press the edges of
the outer tyre into the spaces below the flanges.
2. The combination of a concave metal rim having inwardly projecting flanges
along each of its side edges-a flexible outer cover or tyre of U form having its
edges adapted to fit below the flanges-a tube of less diameter than the outer cover
surrounding the rim and which when inflated will press the outer cover against the
flanges and form air tight joints between the cover and rim-a branch inflating
tube fitted with a valve extending from this tube through the rim for inflating the
tube and another similar inflating tube fitted with a valve carried through the rim
and through the tube which surrounds it for inflating the cover substantially as
described.
3. A pneumatic or air-tyre constructed substantially as described and illustrated
in the drawings annexed.
1000
WM. THOS. SHAW.
ARTHUR SYDENHAM.
1. W. BOOTHROYD.