Improvements in Pneumatic Tires.
Year: 1896

page_text: Date of Application, 24th Dec., 1896
Complete Specification Left 8th Sent 1897 Accepted 18th Dec. 1897
PROVISIONAL SPECIFICATION.
Improvements in Pneumatic Tires.
I DENIS DOYLE Youghal Co. Cork Workhouse Master do hereby declare the
nature of this invention to be as follows:-
Its object is to give the tire a greater extent of resiliency by increasing its
depth; and at the same time to diminish its friction on a hard road but increase
the grip on a slippery road by reducing its breadth at the point of contact with
the ground.
I accomplish this by attaching a web crosswise internally so as to hold bo.h
sides of the outer cover more closely together, thus causing the section of same
to be somewhat like the figure 8 instead of, as at present, being circular. I
then introduce a pneumatic tube of say inch or " bore in the outer ring and
another of say 17 or 1 bore in the inner ring.
The said web, to be fitted all round, at intervals of say of an inch with
hooks & eyes to admit of the outer ring being opened to repair punctures in
the tube therein encased. This tube may have a separate inlet & valve to
provide for its being pumped harder than the inner tube.
I also fix this webb on a tubeless tire, the hooks & eyes being unnecessary.
But Instead of a webb held together with hooks and eyes I use a series of corls
of sufficient strength & fastened crosswise like the letters XXX Thus the spaces
between the Xs admit the finger for the purpose of repairing a puncture. Non
puncturable tires may be used with great advantage and two or more webbs
may be used so as to give the tire the sectional shape of an isosceles triangle with
its apex-the part bearing on the road rounded.
Improvements in Pneumatic Tyres.'
I, DENIS DOYLE, Workhouse Master of Yougal, in the County of Cork
Ireland, 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 chief object of these improvements is to reduce the waste of motive
power caused by the friction of the tyre with the road.
It is a well known fact that for ordinary bicycles the 2" tyre is slower than
the tyre though the former absorbs vibration better. The reason of this is

page_text: that the tread or that portion of the tyre that comes in contact with the road
is wider.
Now by my invention I give the tyre a depth of say 2" or more, but I decrease
the tread even to less than that of the 1 tyre, thus securing less friction, and
in this way I accomplish the maximum amount of resiliency with the minimum
of friction. My invention has the further advantage of gripping a slippery road
like the old solid tyres.
The diagram herewith represents my new tyre in section. O C is the outer
Cover. To its sides are fastened strips of canvas M D these meet in the middle
& overlap each other being held in position by hooks & eyes H inserted at
intervals of a half inch more or less. Lacing like that of boot may be used
instead of hooks. In this way the tyre is made to have two chambers in each
of which an ordinary pneumatic rubber tube P N is enclosed. The outer tube
is inflated by a separate valve V in wheel rim R through the small tube T
placed between the inner pneumatic chamber N and the outer case C. To take
out the outer pneumatic tube for repairs &c it is only necessary to untie the
hooks.
In order to make the outer tube sit true over the inner one care must be taken
to fasten or hook on the outer cover at either side to the wheelrim as shown
at K K or by some other suitable attachment.
The pneumatic tubes can be of any required size to suit the weight & nature
of the vehicle.
I prefer to have separate valves as above described so that the outer one may
be pumped harder & if the outer tube becomes punctured the inner one may
still be used, but I also make this tyre with only one valve by simply connecting
one tube with another, so that the air supplied to the inner tube passes also to
the outer one and inflates it.
Having now particularly described & ascertained my said invention & n
what manner the same is to be performed I declare that what I claim is:-
Increasing the efficiency of a pneumatic tire by reducing the area of contact
of same with the road or path on which it travels, without at the same time
decreasing the depth of the tire (& consequent capacity for absorbing vibration),
by causing the sides of tire to be brought closer together thus elongating its
section substantially as above described."
D: 4th Day of Santamba 1907