Improvements in or relating to Pneumatic Tyres for Wheels.
Year: 1893

page_text: Date of Application, 8th Mar., 1893
Complete Specification Left, 7th Dec., 1893-Accepted, 13th Jan., 1894
PROVISIONAL
SPECIFICATION.
Improvements in or relating to Pneumatic Tyres for Wheels.
A communication from L. ROCHET & Co., of 74, Rue de la Folie Regnault, Paris,
in the Republic of France, Manufacturers.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
-
The object of this invention is to provide an improved pneumatic tyre which
owing to its peculiar construction offers over the tyres hitherto employed the
advantage of retaining its position upon the rim of the wheel without any danger of
its accidentally slipping or shifting therefrom, this result being obtained without
the assistance of any wedges or means of attachment whatever and the secure
connection obtained being quite independent of any pressure that may exist within
the air-chamber.
The improved tyre consists of an air-tube preferably of indiarubber and which
may be inflated by any ordinary means such as a pump. This tube is enveloped in
a cover the two edges of which have two hoops of wire let into them. These
boops are endless i.e. without any break and have an invariable diameter. The rim
of the wheel which is hollow is cut between two spokes so as to leave between the
two ends a space of say 20 millimetres which space is covered by a sleeve or joint-
guard. This guard is brazed, soldered or otherwise suitably secured to one end but
slides freely upon the other end which it fits exactly.
Two nuts brazed or otherwise fixed the one within the one end of the rim, and
the other within the other end of the same are screw-threaded in opposite
directions, and connected by a double bolt so that when the said bolt is turned by
means of a key or equivalent passed through an opening which may be provided in
the guard the two ends of the rim may be brought closer together or moved farther
apart as desired.
The method of fitting the tyre on to the wheel will now from the foregoing
description, be readily understood.
By turning the bolt in the manner. just stated in the desired direction, the two
ends of the rim are inade to approach each other, whereby of course, the diameter
of the rim is correspondingly diminished.
The air-chamber is then inserted in the deflated condition into the cover. All
the parts are then arranged in position upon the rim without there being any
resistance to overcome on the part of the hoops, as the decrease of the diameter of
the rim previously obtained by narrowing the space between its ends has been so
calculated as to euable the said circles to pass over it freely.
It now only remains to turn the screw-bolt in the opposite direction so as to move
asunder again the ends of the rim to the fullest extent, and when this is done a
sufficiently tight connection will be obtained between the rim and the hoops which
being firmly pressed home, into the rim, or a channel therein, as it were, make the
diameter of the rim as invariable as their own and thereby effectually prevent any
displacement of centres.
It will be observed that the operation of the double screw-bolt in addition to:
causing the ends of the rim to move away from each other, has the effect of
stretching the spokes of the wheel, which, when the ends of the rim are screwed up
close to each other, for the purpose of fitting the tyre in position, must be slightly:
bent.

page_text: The air-chamber is now inflated, and this being the last operation completes the
whole fitting and produces a wheel ready for immediate use...
It will be readily understood also that when by turning the screw-bolt the two
ends of the rim are moved. apart a sufficient distance, this will cause the metal
hoops upon the edges of the cover to sustain a tight pressure exercised by the rim
so that the indiarubber cover will under no circumstances be able to slip or creep
upon the metal surface of the rim.
Deted thin 9th dom
1000
COMPLETE SPECIFICATION.
Improvements in or relating to Pneumatic Tyres for Wheels.
A communication from L. ROCHET & Co., of 74, Rue de la Folie Regnault, Paris,
in the Republic of France, Manufacturers.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent 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 :-
The object of this invention is to provide an improved pneumatic tyre which
owing to its peculiar construction offers over the tyres hitherto employed the
advantage of retaining its position upon the rim of the wheel without any danger of
its accidentally slipping or shifting therefrom, this result being obtained without
the assistance of any wedges or means of attachment whatever and the secure
connection obtained being quite independent of any pressure that may exist within
the air-chamber.
The invention is illustrated in the accompanying drawings, wherein
Fig. 1 is a perspective view of the tyre at the moment of mounting it on the rim.
Fig. 2 is a view of the same when mounted, partly in section showing the sleeve
and internal devices.
Fig. 3 is a longitudinal section of Fig. 2.
According to this invention the tyre is formed by an air-chamber of rubber. C
which may be inflated in the ordinary manner i.e. with an air-pump. The air-
chamber is enclosed in a rubber or equivalent cover E, whereof each edge is fitted
with a metallic wire ring e embedded in the material of the cover, and perfectly
continuous of a diameter exactly fixed.
The wheel-rim, which is hollow is cut in two, between two adjacent spokes, so.as
to leave an open space of 20 millimetres or so, between the severed ends J J A
sleeve or joint-cover M of adequate length is brazed soldered or otherwise suitably
secured on the end J and slides freely over the end J' thus enclosing and covering
the severed ends and the intervening opening.
The screw-nuts A and A' brazed or otherwise fixed inside the rim, respectively,
the one near the end J the other near the end J¹ are tapped in contrary directions,
and joined together by a double screw-bolt, having a solid hexagonal centre and the
two bolt-ends screw-threaded also in opposite directions. An opening m is cut in
the sleeve M for the introduction of a spanner; and when the nuts are brought into
juxta-position with the ends of the double-bolt, the latter on being turned by the
wrench or spanner, engages with their contrary threads and draws them, and the
rim-ends to which they are attached together while the contrary motion separates
them.
The method of mounting the pneumatic tyre on the wheel-rim is now easily to be
understood.
By suitably turning the double bolt, the extremities J J' of the rim are brought

page_text: together, while at the same time the diameter of the rim is temporarily reduced,.
until the fixed. rings e of the cover can be slipped on, owing to that contraction,
their diameter having been duly calculated beforehand.
The air-chamber Č in its uninflated state is then encased in the cover E and the
whole tyre is mounted on the wheel-rim (as shown in Fig. 1) which can readily be
done, as above explained.
All that has now to be done is to turn the double-bolt B in the reverse direction,.
so as to separate the screw-nuts and the ends J J' of the rim, enlarging the
diameter of the rim ; the bolt must be screwed home, until the two rings e of the
cover are tightly encircled round the hollow of the rim (as shown in Fig. 2).
whereof the working diameter is thereby invariably fixed and determined; and by
this alone all lateral displacement of the tyre from the central line of the wheel is.
effectually prevented.
It may here further be observed that the same effect of the double-bolt, namely
the separation of the nuts and extension or expansion of the wheel-rim tends to
exert a tension upon the spokes and tighten them up in their places, they having
previously been somewhat relaxed and thrown out of centre, during the time of
bringing the ends of the rim together and contracting the diameter of the wheel
preparatory to mounting the tyre.
Finally the inflation of the air-chamber. renders, the operation of mounting the
tyre complete.
It will be readily understood how in consequence of the separation of the
extremities of the rim by the turning of the double-bolt B the two metallic wire
rings e united so as to be one with the edges of the tyre-cover E will thus be
tightly strained round the hollow of the rim, so that by no possibility and under no.
circumstance can any sliding of the rubber cover take place along the metal
surface of the wheel-rim.
Any suitable device other than the above described screw bolt may be employed
for moving or holding the divided tyre without departing from the spirit of this
invention; the sleeve also may slide upon the rim without being permanently fixed
to either part.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondents and in what manner the
same is to be performed I declare that what I claim is ;-
1. A tyre composed of an ordinary air-chamber or tube encased in a rubber or
equivalent cover whereof the edges are provided with wire or equivalent non-
stretchable rings closed and rigid in combination with a hollow wheel-rim cut in
two at one point of its periphery and whereof the two ends are provided with two
fixed nuts tapped with contrary screws which can at will be brought together to
permit the mounting of the tyre or separated for the purpose of straining the edges
of the cover and the rings associated therewith forming parts of the said tyre
within the groove or hollow of the rim so as to prevent sliding or displacement of
the tyre on the rim.
2. Securing a pneumatic tyre upon the wheel rim by dividing the rim and
separating the ends substantially as described.
Dated this 7th day of December 1893.
W. P. THOMPSON & BOULT,
Of London, Liverpool, Nottingham, and Manchester,
Agents for the Applicant.