An Improvement in Elastic Tyres for Wheels.
Year: 1892

page_text: Date of Application, 20th July, 1892
Complete Specification Left. 17th Apr., 1893-Accepted, 27th May, 1893
PROVISIONAL SPECIFICATION.
An Improvement in Elastic Tyres for Wheels.
I, FREDERICK BASS, of 17 Charterhouse Square, in the County of London,
Surgeon, do hereby declare the nature of this invention to be as follows:-
My invention relates to a construction of elastic tyres for wheels so as to avoid
all danger of gaping when they are cut, and to fix and hold the tyre without screws
the use of cement or of hooks, holdfasts or other moveable fixings. The con-
struction also is such that an injured portion of the tyre can be readily removed
and replaced by a new portion, also that the whole tyre may be exchanged for a
tyre of different section applied to the same rim. For this purpose, I make the
metal rim with a groove having a lip on each side turned inwards, and I provide a
number of pieces or voussoirs of caoutchouc or other suitable elastic material or
compound of such a shape that the one side fits into the hollow of the rim and the
other projecting beyond the rim is of any suitable form for operating as a tread. I
pack these voussoirs, (each of which may be of any convenient thickness such as an
inch) into the hollow of the rim side by side so as to fill it completely up, the last
piece or pieces being inserted while those already in the rim are under compression
the whole being thus effectually tightened in position:
The voussoirs may be either homogeneous or may have portions of their com-
position softer or stiffer as may be desired, and they may be strengthened if
necessary by metal pieces included in them.
Dated this 20th day of July 1892.
ABEL & IMKAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Elastic Tyres for Wheels.
I, FREDERICK BASS, of 17 Charterhouse Square, in the County of London,
Surgeon, 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 :-
My invention relates to a construction of elastic tyre for wheels by which all
liability of the tyre to gape when cut, is minimised, and by which the tyre is held
and fixed to the rim without wire, screws, hooks, or the like, and without the use
of cement or adhesive composition. The construction also is such that any portion
of the tyre can be readily removed and replaced by a new portion. The whole tyre
may moreover be easily exchanged for a tyre of different section applied to the
same rim; such removal and replacement does not require special knowledge or
skill, but is capable of being performed by any person of ordinary intelligence.
According to my invention I construct the metal rim of the wheel with a circum-
ferential groove and a lip on each side turned inwards, and I provide a number of
pieces or segments of caoutchouc or other suitable material or compound, of. such
a shape that one part of each segment is adapted to be received in the aforesaid
groove, the other part projecting beyond the rim and forming the tread portion of
the wheel. The segments are inserted singly or in convenient numbers into the
hollow of the rim, until the whole circumference is completely filled. It is not
necessary for my purpose that the said segments should fit accurately, but it is
essential that the width of that part of the segment which is received into the
groove of the rim below the lips should be somewhat greater than the distance
between the lips of the rim.

page_text: position softer or stiffer as may be desired, or they may be strengthened by metal,
or other pieces of hard material, included in them.
In order that my invention may be more clearly understood I will now proceed
to describe the same by the aid of the accompanying drawings, in which
Figure 1 is a side elevation showing part of a wheel rim fitted with a tyre con-
structed according to my invention.
Figure 2 is a transverse section of the same:
Figure 3 is a side elevation, and
Figure 4 is a section shewing a modification of the same.
Figure 4 is an edge view of one of the strips detached.
Figures 5 to 18 are side elevations and corresponding sections, shewing further.
modifications of my invention.
Figure 19 is a view shewing a tool which I use in inserting the segments,
forming the tyre, in place in the rim of the wheel, as will be hereinafter explained.
Like letters of reference denote similar parts in all the drawings.
A is the rim of the wheel, and B, B', are the segments forming the tyre.
Referring now to Figures 1 and 2, the metal rim A is made with two inwardly
projecting lips A' A' forming a dovetail circumferential groove into which the
base B of each segment fits more or less accurately, as shewn in the section
Figure 2.
The segments are inserted as above mentioned either singly or in groups, and
when the rim is filled up so that no more segments can be packed in by hand, I
use a mechanical device for forcibly separating two adjacent segments to allow of
one or more additional segments being inserted. Any instrument which can effect
this forcible separation of adjacent segments may be used. A convenient instrument
for this purpose is shewn in Figure 19 where CC are two pieces forming a wedge
when placed together, which pieces can be moved away from each other, as shewn
in dotted lines, by turning a rod or spindle D having a right-handed and a left-
handed screw which engages with the two parts of the wedge, that is to say, one
part of the wedge is in engagement with the right-handed screw, and the other with
the left-handed screw.. The parts C of the wedge having been closed, are inserted
between two adjacent segments of the tyre; then on turning the rod or spindle
the said parts of the wedge are separated, leaving a space between them which is
then filled up by the insertion of more segments. The instrument is then with-
drawn, and the process repeated in other parts of the circumference of the tyre,
until all the segments of the same are under firm mutual pressure.
Owing to the mutual pressure of the segments towards the end of the packing
process, the said segments expand transversely, and are thus very firmly secured
in place. Moreover since the segments are compressed, a cut made therein does
not tend to gape as is the case in continuous tyres which are more or less in a state
of tension, but on the contrary closes at once.
The elastic segments may be made in short lengths or in the form of thin
laminæ. When india-rubber is used it may be vulcanized in a mould of the
proper shape after the ordinary method, or the lamina may be punched out of
rubber sheet or waste, the thickness of the segments not requiring to be uniform.
In Figures 3 and 4 shew a rim which is approximately circular in section
having a slot, which is less in width than the internal diameter of the groove in
the rim, formed in its outermost periphery. The segments B are made of a
symmetrical shape as shewn, and are thus reversible.
In Figures 5 and 6, the segments, which are preferably thin, are not radial in
their entirety, but have their peripheral halves inclined backwards as shown in the
side elevation. The rim is of U section with inwardly sloping sides forming the
dove-tail groove which receives the wedge-shaped bases B¹ of the segments.
I sometimes make the segments hollow with one or more air spaces in each.
The said air spaces may also contain in them loose elastic bodies to act as buffers.
Examples of such modifications of my invention are shewn in Figures 7 to 10.

page_text: In Figures 7 and 8 the rim is of the form shewn in Figure 6 and the segments are
shaped externally as shewn in Figure 4 and 4 but are provided with an air
space B. In Figures 9 and 10 the rim is of the form shewn in Figure 4 and the
segments of another pattern.
In the tyres shewn in Figures 11 to 16 the solid segments have pieces of spongy
rubber or of hollow rubber, interposed between them and the bottom of the groove
in the metal rim. The spongy or hollow rubber segments are entirely enclosed
within the rim, the inwardly turned edges A' of which engage with the narrow
parts of the solid outer segments. The said outer segments are so designed as to
allow the same to move radially in or out as shewn very clearly in Figure 14 for
instance.
In Figures 15 and 16 the hollow segments are partially filled with an elastic
body E, made of cork for example, loosely contained therein.
I sometimes dispense with the air containing segments, and use instead thereof a
flat steel spring coiled spirally on itself as shewn at F Figures 17 and 18.
When it is desired to remove any portion of my improved elastic tyre from
the rim, the instrument herein before described and shewn in Figure 19 may be
used. The wedges C, C, are drawn apart wide enough to enclose the segment or
segments it is desired to extract, and are then forced into the tyre one on each
side of the said segment or segments. The wedges are now forced further apart
by turning the rod or spindle so as to relieve the segment or segments between
them from the pressure of the others on each side of the same, the segment or
segments can then be very readily extracted and new ones if necessary inserted.
My improved tyre is thus very readily repaired. It is moreover economical and
very cheap and casy of construction. For wheels of vehicles intended to carry
heavy loads, or where broad wheels are required, I may provide the metal rim
with more than one groove each fitted with segments as above described.
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. The combination, with a wheel rim having a circumferential groove formed
therein, of elastic segments constituting the tyre inserted in said groove, said
segments being constructed so as to be held in position by the sides of the groove
and by their firm mutual pressure on each other, for the purpose specified.
2. The combination, with a wheel rim having a circumferential groove formed
therein, of elastic segments constituting the tyre inserted in said groove, each said
segment being enlarged at its inner end at the part enclosed by the rim, sub-
stantially as described for the purpose specified.
3. The segments B, B1 having a constricted part at or near their middle in com-
bination with a grooved wheel rim with or without metal or other pieces of hard
material included in them, substantially as, and for the purpose, specified.
Dated this 17th of 1000
FREDERICK BASS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.