Improvements in or Additions to Elastic Wheel Tyres, and in Means of Fixing the same.
Year: 1889

page_text: Date of Application, 19th Jan., 1889
Complete Specification Left, 19th Oct., 1889-Accepted, 23rd Nov., 1889
PROVISIONAL SPECIFICATION.
Improvements in or Additions to Elastic Wheel Tyres, and in
Means of Fixing the same.
I, GEORGE HOOKHAм, of 7 & 8 New Bartholomew Street Birmingham Manufacturer
do hereby declare the nature of this invention to be as follows:-
Referring to the complete specification of Letters Patent, granted to me, the said
George Hookham, and numbered 3778/1886 in which is described, and claimed a
metal core for an elastic Wheel-Tyre, the said core having a limited longitudinal
elasticity-it has been found advisable in practice to use for the tyre india-rubber of
a quality possessing exceptional toughness, and specially high breaking strain, in
order to prevent the core cutting the tyre. The only quality of india-rubber common
in the trade, so far as I know, that possesses this property has two drawbacks; it is
somewhat hard; and it possesses a comparatively high specific gravity.
To remedy, or diminish these practical or commercial defects, I now propose to use
a composite tyre of the following description. An inner core (having a small axial
hole for the insertion of the spring core) is formed of this specially tough india-
rubber, or, either instead, or in addition, a binding of canvass or other fibrous or
strengthening material is used, and this inner core may be surrounded by a lighter
& softer india-rubber-Care must be taken as to the lubricant used on the wire
mandrill in the process of manufacture, as some lubricants, e.g. French chalk, would
interfere with the union of the two layers of india-rubber. I have found petroleum
jelly, or " vaseline " a good lubricant."
In some cases I have found manufacturers unwilling to dispense with coment
altogether. I accordingly some-times form a core, which may consist of a com-
paratively weak spring, there being moulded upon it india-rubber (which may be of a
cheaper quality) so as to form a complete ring, the ends of the spring core being
joined. India-rubber of a better quality may be superposed upon this, and the whole
placed in a mould in such a way, that the core containing the spring lies closely
against the smallest diameter of the mould, and so that when the completo tyre is
fixed on a wheel, this composite core lies at the bottom of the rim with the rest of the
india-rubber in shape (in section) of a crescent around, and above it. The cement is,
by preference, applied in the form of a tape, strip, or wire, and may be wound for
packing on pegs fixed in a board.
I do not confine myself to a metal core for supplying the spring in use with coment.
Nor do I necessarily make the core eccentric. It may be axial, and in any case
(whether the rubber for the tyre be manufactured in a ring or in a long length) I
may form the india-rubber for the tyre by winding it as a strip helically on the core ;
and I may add a canvass, or other fibrous, or strengthening binding to prevent cutting
by the core. If I desire to supply the cement in the form of tape, strip or wire,
unsupported by fibrous, or other strengthening material, I may cause the hot liquid
cement to flow through an aperture, having the form of the desired section, into cold
water. In some cases I supply the cement on the tyre itself, ready for fixing.
Dated this 18th day of January 1889
GEORGE HOOKHAM.

page_text: COMPLETE SPECIFICATION.
Improvements in or Additions to Elastic Wheel Tyres, and in
Means of Fixing the same.
I, GEORGE HOOKHAM, of Nos. 7 & 8 New Bartholomew Street, Birmingham,
manufacturer 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 :-
Referring to the complete Specn. of Letters Patent granted to me, the said George
Hookham & numbered 3778/86 in which is described & claimed a metal core for an
elastic wheel-tyre, the said core having a limited longitudinal elasticity, it has been
found advisable in practice to use for the tyre india rubber of exceptional toughness,
and specially high breaking-strain, in order to prevent the core cutting the tyre. The
only quality of indin-rubber cominon in the trade, so far as I know, that possesses
these qualities has two drawbacks it is somewhat-hard, &-has a comparatively high
specific gravity.
To remedy or diminish these defects I now propose to use a composite tyre of the
following description. An inner core (having a small axial hole for the insertion of
the spring core) is formed of this specially tough india-rubber, or, either instead or
in addition, a binding of canvass, or other fibrous or strengthening material is used,
and this inner core may be surrounded by a lighter and softer india-rubber. Care
must be taken as to the lubricant used on the wire mandrill, as some lubricants, as
e.g. French chalk, would interfere with the two layers of india-rubber. I have found
petroleum-jelly or 'vaseline' a good lubricant..
In some cases I have found velocipede manufacturers unwilling to dispense
altogether with coment. -1-accordingly sometimes form a core which may consist of a
comparatively weak spring, there being moulded upon it india-rubber (which-may be
of a cheaper quality) so as to form a complete ring, the ends of the spring core being
joined. India-rubber of a better quality may be superposed upon this, and the whole
placed in a mould in such a way that the core containing the spring lies closely against
the smallest diameter of the mould, and so, that-when the complete tyre is fixed on
a wheel, this composite core (consisting of the metal core surrounded by the harder
india-rubber) lies at the bottom of the rim, with the rest of the india-rubber in shape
(in section) of a crescent around & above it. The cement is, by preference, applied
in the form of a tape or strip, and may be wound, for packing, on pegs or nails fixed
in a board.
I do not confine myself to a metal core in use with cement: nor do I necessarily
make the core eccentric. It may be axial, and in any case (whether the rubber for
the tyre be manufactured in a rim or in a long length) I may form the india-rubber
for the tyre by winding it as a strip helically on the core, or on a plain wire that
is afterwards withdrawn and I may add a canvass or other fibrous or strengthening
binding to prevent cutting by the core. In some cases I supply the cement on the
tyre ready for fixing.
I have found in practice that the tape or other fibrous or strengthening material
on which the cement is spread should be of very open texture. In order to produce
my tape-cement, as above described, I melt a quantity of ordinary cement in a vessel,
immerse in it the fibrous tape, and then draw the tape with the cement upon it, through
a slit in the lid of the vessel; the slit being about as long as the breadth of the tape,
and adjusted for width so as to allow a coating of cement on the tape of the thickness
required.
Having now particularly described, and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what 1
claim is
1. A composite india-rubber tyre consisting of a core of harder india-rubber having
a small axial hole, this core being surrounded by softer india-rubber united to it sub-

page_text: 2. A tape cement, the same being either a separate article of manufacture, or
affixed to an india-rubber tyre substantially as above described.
3. An india-rubber tyre with cement attached ready for fixing, substantially as
described.
101
1000
GEORGE HOOKHAM.