Improvements in Elastic Tyres.
Year: 1891

page_text: Date of Application, 1st Dec., 1891
Complete Specification Left, 26th Jan., 1892-Accepted, 27th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements in Elastic Tyres.
A communication from CURT WAGNER, of Oederan, in the Empire of Germany,
Merchant.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., do hereby declare the nature of this invention to be as follows:-
The tyre which forms the subject of this invention differs from the usual india-
rubber tyres, both solid and hollow (or pneumatic) in the arrangement within it of
one or more springs adapted to sustain and compensate the weight of the vehicle,
the external casing or cover forming the tyre proper and enclosing such springs
being made of any suitable elastic material.
The arrangement in its simplest form consists of a spiral spring placed round the
felloe or rim of the wheel, the spring being either flat or of circular section. A
number of separate springs of substantially circular shape may also, however, be
arranged round the periphery of the wheel and rivetted thereto one by one.
the springs may be secured beforehand to one continuous band or hoop to be passed
over or embodied in the felloe.
Or
Spring controlled tyres of this description share the advantages of the ordinary
pneumatic tyres in that they are extremely yielding and productive of easy and
smooth motion; while they do not participate in the inconveniences of the pneumatic
tyres, which when in the least damaged remain inoperative unless constantly refilled
with air. A further important advantage of the improved tyre herein described is
that the external casing or covering of indiarubber or the like may when worn out
be replaced with facility and at little cost.
The peculiarity of these spiral springs is that they are wound in such a manner
as to form alternately large and small convolutions. By this method of winding
various objects are attained, though it does not necessarily exclude the employment
of any ordinary spiral spring, the employment of which would be within the scope
of this invention. Ordinary spiral springs however are likely to present this
disadvantage that, the outer circle of the wheel being of course the largest one, the
convolutions of the springs would radiate towards the outside, i.e. be spread further
apart externally and be further compressed inwardly, and in so doing it is to be
feared that they will form too wide spaces between them to be of any service as
supports of the external covering or tyre proper. The form of spiral springs.
described avoids this drawback by enabling the convolutions to be set close together
at the periphery of the wheel while at the same time leaving sufficient play for the
larger convolutions to be radially compressed within, a sufficient and equally divided
support being thus afforded to the exterior elastic ring, Half of the spring being
moreover embedded in the elastic tyre the upper half only of each convolution sustains
and yields to the weight of the rider and if an ordinary spiral spring were used, its
convolutions would be liable to be bent out of shape at the top which is the part
most strained. This again is avoided by the arrangement described in which the
yielding power of the spring is equally divided throughout the circle owing to the
compensating action of the small loops alternating with the large ones. The felloe
or rim is semi-circular in section and provided with angular flanges into which are
inserted the edges of the external indiarubber band or tyre proper which is retained
in this position by the spring it encloses. The fastening of the indiarubber or the
like may however be effected in any other suitable manner if required. To prevent
a displacement of the spring in relation to the rim of the wheel it may be stretched
round an iron band or hoop passed over the rim and to which some of the convolu-
tions situated at given intervals apart may be rivetted or screwed.

page_text: In a modification the springs are bent circularly so that their ends overlap and
are secured at their centre to the wheel rim.
If an indiarubber band be used care should be taken that the material is of the
very best quality such as is now used in preference for pneumatic tyres, so that the
danger of its being injured by the metal spring is obviated, and the rubber band
may for this purpose be further protected by the interposition of a strip of a suitable
strong fabric between it and the spring or springs.
Dated this 1st day of December 1801
Improvements in Elastic Tyres.
A communication from CURT WAGNER, of Ocderau, in the Empire of Germany,
Merchant.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,.
M.I.M.E., 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 tyre which forms the subject of this invention differs from the usual india-
rubber tyres, both solid and hollow (or pneumatic) in the arrangement within it of
one or more springs adapted to sustain and compensate the weight of the vehicle,
the external casing or cover forming the tyre proper and enclosing such springs,
being made of any suitable elastic material.
The arrangement in the simplest form consists of a spiral spring placed round the
felloc or rim of the wheel, the spring being either flat or of circular section. A
number of separate springs of substantially circular shape may also, however, be
arranged round the periphery of the wheel, and rivetted thereto one by one.
the springs may be secured beforehand to one continuous band or hoop to be passed
over or embodied in the felloe.
Or
Spring-controlled tyres of this description share the advantages of the ordinary
pneumatic tyres in that they are extremely yielding and productive of easy and
sinooth motion while they do not participate in the inconveniences of the pneumatic
tyres which when in the least damaged remain inoperative unless constantly refilled
with air. A further important advantage of the improved tyre herein described is
that the external casing or covering of indiarubber or the like may, when worn out,
be replaced with facility and at little cost.
In the accompanying drawings I have represented some of the forms in which
this invention may be carried out, Figures 1 to 5 showing the arrangement of one
continuous spiral spring and
Figures 6 to 9, a modification in which a series of separate springs are employed.
In Figures 1 to 3 it is assumed that the spiral spring is flat and in Figures 4
and 5 it is shown to be of circular section. The peculiarity of these spiral
springs is that they are wound in such a manner as to form alternately large
convolutions a and small convolutions b. By this method of winding various
objects are attained, though it does not necessarily exclude the use of any
ordinary spiral spring the employment of which would be within the scope of
this invention. Ordinary spiral springs however are likely to present this
disadvantage that the outer circle of the wheel being of course the largest one
the convolutions of the spring would radiate towards the outside, i.e. be spread
further apart externally and be further compressed inwardly, and in so doing
it is to be feared that they will form too wide spaces between them, to be of
any service as supports of the external covering or tyre proper. The form of
spiral springs represented in the drawings avoids this drawback by enabling the

page_text: convolutions to be set close together at the periphery of the wheel while at the
same time leaving sufficient play for the larger convolutions to be radially
compressed within; a sufficient and equally divided support being thus afforded
to the exterior elastic ring. Half of the spring being moreover embedded in
the elastic tyre, the upper half only of each convolution sustains and yields to
the weight of the rider, and if an ordinary spiral spring were used its convolu-
tions would be liable to be bent out of shape at the top which is the part
most strained. This again is avoided by the arrangement shown in which the
yielding power of the spring is equally divided throughout the circle owing to
the compensating action of the small loops or convolutions & alternating with
the large ones_a. c is the felloc or rim semi-circular in section and provided
with angular flanges d into which are inserted the edges of the external india-
rubber band or tyre proper e which is retained in this position by the spring
it encloses. The fastening of the indiarubber or the like may however be
effected in any other suitable manner if required. To prevent a displacement
of the spring a b in relation to the rim of the wheel an iron band or hoop f
may be passed through the larger convolutions and around the rim and some of
the convolutions, at suitable intervals apart may be rivetted or screwed to it.
The arrangement shown in Figures 6 and 7 differs from that which has just been
described in this particular only that instead of one continuous spring a series of
individual springs aba are here employed, the wider convolutions a meeting in
pairs at g upon the rim of the wheel to which the ends of these springs a are rivetted
or otherwise secured.
In the modification shown in Figures 8 and 9 the springs a¹ are bent circularly
so that their ends overlap and are secured at their centre to the wheel-rim at h.
If an indiarubber band or covering e be used care should be taken that the
material is of the very best quality such as is now used in preference for pneumatic
tyres so that the danger of its being injured by the metal spring is obviated, and
the rubber band e may for this purpose be further protected by the interposition of
a strip of a suitable strong fabric between it and the spring or springs.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is :-
1. A spring tyre for cycles consisting of a rim or felloe of semi-circular section
in which is laid either one spiral spring or a series of circular bent springs covered
with a strip of a suitable elastic material the edges of which are tightly fitted and
secured to the rim of the wheel substantially as described.
2. The employment in a wheel tyre of a spring composed of alternately large and
small convolutions substantially as described.
3. The combination with a wheel tyre of a number of independent springs such
as ab arranged in close sequence substantially as described and illustrated in
Figures 6 and 7 of the accompanying drawings.
4. The combination with a wheel-tyre of a number of independent springs such
as a with their free ends turned inwards and out of contact with each other
substantially as described and illustrated in Figures 8 and 9 of the accompanying
drawings.
Dated this 26th dow of Januo 1800
ALFRED J. BOULT,
Chartered Patent Agent.