Improvements in Tyres for Wheels.
Year: 1896

page_text: Improvements in Tyres for Wheels.
I, WILLIAM TATHAM of Summerhill House, Tunbridge Wells, Gentleman, do
hereby declare the nature of this invention to be as follows:-
My invention relates to an improved elastic tyre for wheels and it consists of a
spirally coiled steel spring which is openly coiled but when applied to the wheel is
in compression, the coils being then close together so that the spring tends to
expand radially but is retained by the converging flanges of a channelled or other
suitable metal rim which embrace the spring tyre sufficiently to prevent it flying
outwards whilst leaving sufficient of the coil exposed to form the tread.
In order to deaden noise rubber, leather, or other suitable material may be
interposed between the coiled tyre and the rim in the form of a lining for the
latter or otherwise, the function of this lining being to prevent metallic contact
and not to impart resiliency, since the coil being in a state of compression is
inherently resilient since when pressed inwards by the weight of the load it
rebounds or regains its original form as soon as the load is removed.
In order to prevent the coil creeping in the circular direction by the action of
the brake it is secured at intervals to the rim in such a way as not to interfere
with its resiliency in the radial direction of the wheel and preferably by making
the convolutions of the coil at such intervals of a long oval forn so as to project
radially of the wheel into sockets formed in the rim or felloe whereby creeping
will be prevented without impeding the radial play of the spring tyre.
In order that the spiral coil may present a practically continuous surface at the
tread the wire from which it is made may be of variable width the variation
depending on the intended diameter of the coil and of the wheel to which it is to
be applied so that when in compression the coils will not be in greater proximity
to each other at the inner circumference thau at the outer circumference or tread
of the spring tyre.
Dated this 11th day of March 1896
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Tyres for Wheels.
1, WILLIAM TATHAM of Summerhill House, Tunbridge Wells, Gentleman, 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 an improved elastic tyre for wheels and it consists of
an openly coiled spiral steel spring which when applied to the wheel is in such a

page_text: state or compression in the circumferential direction of the wheel that the coils are
brought close together and the tendency to expand radially is sufficient to afford
the resiliency required. The spring is retained in compression by the converging
flanges of a metal rim which embrace the spring tyre sufficiently to prevent it
flying outwards whilst leaving sufficient of the coil exposed to form the tread.
The coil does not normally bed against the bottom of the channelled rim since the
tendency to expand keeps it constantly forced outwards against the flanges but it
may come in contact with it under pressure of the load or of shock, and in order to
deaden noise rubber, leather, or other suitable material may be interposed between
the spring coil and the rim in the form of a lining for the latter or otherwise,
the function of this lining being merely to prevent metallic contact and not to
impart resiliency.
Reference is to be had to the accompanying drawings forming part of this
specification wherein
Figure 1 is a cross section of the improved tyre. Figure 2 is a side view.
Figure 3 shews a portion of the spring before compression, and
Figure 4 shews the form of the spring strip in the straight.
A is the spring tyre formed of a spirally coiled strip of steel of rectangular or
approximately square section and preferably of varying width, as shewn in
Figure 4, the extent and pitch of the variation depending on the diameter of the
coil and of the wheel to which it is to be applied so that the convolutions when
the coil is in compression around the wheel will make close joints and present a
practically continuous surface at the tread. The ends of the coil are butted or
connected together and the coil when thus brought to the circular form is
compressed around the channelled rim of the wheel and is there retained by
the converging side flanges B B. In order to admit of the insertion of the spring
coil the one flange is removable and is bolted or otherwise secured to the wheel
rim. The bottom and sides of the chanuel are lined with rubber or leather as at C
but the spring coil does not bed thereon as in other coiled tyres which merely form
the wearing surface of the tread and depend on the rubber packing for resiliency,
there being in fact a vacant space all round between the spring coil and the lining,
the coil only coming in contact with the lining when the inherent elasticity of the
coil is overcome by the weight of the load.
The resiliency of the compressed coiled tyre is illustrated in Figure 2 which
shews the part of the tyre which is in contact with the ground flattened under the
weight of the load from its normal arched form, without coming in contact with
the lining of the rim.
In order to prevent the coil creeping in the circular direction by the action of
the brake it is secured at intervals to the rim in such a way as not to interfere
with the resiliency in the radial direction of the wheel. The preferred means of
connection is by making certain convolutions a of the coil of a long oval form so as
to project inwards and fit into radial sockets formed in the rim or felloe and thus
prevent creeping without impeding the radial play of the spring tyre.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A wheel tyre formed of a spirally coiled steel spring in compression circularly
around the wheel rim and there confined by converging flanges on the rim or by
equivalent means of retaining it so as to permit its elasticity to come into play in
the manner described.
2. A wheel tyre formed of a spirally coiled steel spring in compression circularly
around the wheel rim and there confined as described, the spring strip being
of varying width so that the convolutions form close joints at the tread as
specified.
3. A wheel tyre formed of a spirally coiled steel spring in compression circularly
around the wheel rim and there confined as described, certain convolutions being

page_text: adapted to form projecting tenons received in sockets in the wheel rim so as to
prevent creeping while permitting elastic play of the tyre in the radial direction as
described.
Dated this 11th day of December 1896
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.