Improvements in and relating to Elastic Tyres for Wheels.
Year: 1898

page_text: Date of Application, 7th Mar., 1898-Accepted, 9th July, 1898
COMPLETE SPECIFICATION.
Improvements in and relating to Elastic Tyres for Wheels.
HARRY PACE, 21, Constantine Road, Hampstead, London, N.W., 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:-
Consists of a tube of steel bent into circular form, inserted in an endless tube
of rubber, the whole being fastened to rim of wheel by a bolt and screw as
hereafter mentioned. In the drawing A is the rubber tube. B the steel tube
and D the bolt.
INNER OR STEEL TUBE.
This steel tube must be of a very fine temper and sufficiently elastic to assume
an elliptical-like form when an indicated pressure or weight (varying with the
nature of the machine or vehicle) is placed upon it, and as soon as the pressure
or weight is released, the tube must immediately return to its circularity. It will
thus be seen that when the wheel is in use the portion of the tyre between the rim
of the wheel and the ground will always be an ellipse, but immediately another
segment of the tyre touches the ground the former portion at once resumes its
circular or tubular shape. As the wheel revolves very quickly these changes from
circle to ellipse and ellipse to circle occur with great rapidity; the effect should
be that of an ordinary pneumatic tyre but with the great advantage of a constant
regular and smooth and even pressure, giving to the rider an agreeable sense of
comfort and ease not otherwise obtainable.
The tempering of the steel tube is a most important and a very essential part
of the tyre; great care and attention must be paid to this particular. The
efficiency of the tyre largely depends on the "springiness" and elasticity of this
tube.
The diameter of tube and the thickness or thinness of the metal necessarily
depends upon the nature of machine or vehicle for which the tyre is intended.
This
The outer side of the tube should have a highly polished or burnished surface
for avoiding and subduing any friction with rubber coating or tube.
would have the effect of throwing off or rejecting any point which might pierce
the rubber.
The steel tube is joined by telescoping one end into the other F on drawing.
One end should be slightly sunk all round from edge backwards for one or two
inches, so that when the junction is complete the surface may be quite flush.
The part of the tube facing the rim of the wheel should have small circular
holes for this purpose called "home" holes-cut in it to admit of passage of bolt
there should be no "play" allowed and they should be accurately cut. Not
less than three of these "home" holes should be made, one to be placed at about
opposite diameter to the telescopic join and one on each side of join as indicated in
diagram Fig. II. They must be so put as to come between the spokes. The
number of bolts will depend upon the size of the wheel.

page_text: In order to insert the bolt, a hole-called for this purpose the
"
entrance or
lateral hole, "E" on drawing-should be cut in the side of the tube a little
distance farther round and away of about from one to two inches from the
"home" hole of just sufficient diameter to allow a fine long nosed pair of pliers
-or other suitable tool-gripping the bolt and rubber washer (mentioned here-
after) being passed to the hole facing the rim of the wheel-the "home hole.
The object of this is to avoid the risk of weakening the elasticity of the steel
tube as might be the case should the holes be placed side by side.
"3
The following is an explanation of drawing. Figure I is a cross section of
tyre shewing the bolt in position in home hole with the under part of head of
bolt resting on rubber washer.
Figure II is a side view of a wheel shewing the tyre fixed. A" outer tube of
rubber. "B" the inner tube of steel. "C" the rim of wheel. "D" the bolt.
"E" the " entrance" hole. "F" the telescopic join. "G" the rubber washer.
OUTER OR RUBBER TUBE.
The rubber tube should accurately fit the steel tube without stretching and
should be of good quality, with the surface bearing on the ground harder than
the rest. The tube should be manufactured in one piece forming a continuous
and circular tube...
For the purpose of placing the bolt in position and of passing the steel tube
into the rubber tube, small horizontal slits parallel to rim should be made in the
side of rubber tube where the lateral or entrance holes occur in steel tube of
only sufficient length to allow the bolt to pass. The slit over the telescopic join
will require to be a little longer. One end of steel tube should be put into this
slit and worked forwards and roundwards until the whole is inside the rubber
tube and the ends should then be telescoped as before described.
Care should be taken in the manufacture to secure each end of the slits in
order that the rubber may not break under the strain.
When all has been fixed the edges of the slits should be brought together and
fastened by a suitable adhesive substance and further secured by wire stitches,
the whole being neatly covered and suitably finished i.e. the stitches and slits
may be hidden from view, and be made to appear like the rest of tyre.
THE BOLT.
This is an ordinary steel bolt with screw nut passed through the "home" hole
of steel tube, as before described--the rubber washer having been first placed in a
position on the bolt-then through the rubber tube or coating, finally through
the rim of the wheel. The nut is then screwed on thus fixing the tyre to the
wheel, as shewn in diagram Figs. I & II.
The top of the head of bolt should be flat while the under should be rounded
in convex form to fit into the concavity of the steel tube as shewn. Between the 4
concavity of steel tube and convexity of under part of bolt a thick rubber
washer G on drawing should be introduced. This will have the effect when the
bolt is tightened or screwed up of helping to subdue and to reduce any vibration.
The rim of wheel next the rubber tube or coating should have a smooth, but
firm surface not too concave; the edges being rounded not squared.
The steel tube of tyre thus rests in a bed of rubber; this further helps to reduce
and to subdue any occurring vibration.
The tyre is constantly inflated owing to the steel tube being finely tempered
acting as a spring preserving its rotundity.
4
It is non-puncturable in the sense that although the rubber may be pierced 5
the steel tube wards off any point principally on account of its hardness, and also
because of the highly burnished surface.
It is vibration-reducing owing to the tube of steel being set in a bed of rubber,
i.e. that part of the rubber tube between the rim of the wheel and the steel tube.

page_text: The head of the bolt is also set in a bed of rubber, formed by the washer placed
between the convexity of under part of bolt and concavity of steel tube.
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 I
claim is:-
An elastic tyre substantially as described and as illustrated and shewn by the
accompanying drawing.
Dated this 11.
1000