Improvements in Velocipede Wheel Tyres.
Year: 1891

page_text: Date of Application, 7th Apr., 1891
Complete Specification Left, 8th Feb., 1892-Accepted, 12th Mar., 1892
PROVISIONAL SPECIFICATION.
Improvements in Velocipede Wheel Tyres.
WILLIAM EDWARD CROWTHER Rock Villas Strand Road Londonderry
Science & Art Teacher do hereby declare the nature of this invention to be as
follows:-
In constructing my improved tyre I make use of an inflated rubber tube similar
to that employed in the well known pneumatic tyre. The interior of the tube is
lined or partially lined with a permanently viscous or plastic material to a thick-
ness of one eighth of an inch or thereabouts. In event of the tyre being punctured
little or none of the contained inflating substance will escape when the puncturing
agent is withdrawn because the plastic or viscous substance will automatically
close up the puncture through itself and form an effective shield over the hole in
the rubber.
In addition to this action a minute quantity of the sticky material may pass into
the whole through the rubber and thus plug the hole or cement together the
divided surfaces. The plastic material may otherwise be situated between some of
the several layers of which the tyre is built up.
For the inflation of the tyre I use gas, preferably carbonic acid gas, in lieu of
air which may be introduced either in the usual manner or without any special
aperture or valve by the employment of a pump, gas reservoir or generator having
a very sharp point which is forced into the interior of the tyre through the rubber
and plastic lining. When the point of the instrument is withdrawn after inflation
the hole becomes automatically closed as above described.
For the greater convenience of inflation I prefer to employ a small tubular
reservoir of liquid carbonic-acid gas, containing say 1000 complete charges of the
tyre, fitted with a suitable tap or valve for allowing a minute quantity of gas to
pass into the tyre. This small tubular reservoir may be permanently fixed upon
the rim of the wheel and instead of a tap may be provided with a reducing valve so
arranged and connected as to ensure the maintenance of constant pressure within
the tyre even though leakage takes place. The reservoir or generator may other-
wise be placed upon or within the hub of the wheel and tube or tubular spoke used
to convey the gas to the interior of the tyre.
Dated this 4th day of April 1891
COMPLETE SPECIFICATION.
Improvements in Velocipede Wheel Tyres.
I WILLIAM EDWARD CROWTHER of Rock Villas, Strand Road, Londonderry,
in the County of Ulster, Ireland Science Teacher 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 that type of tyre known as the pneumatic, and it consists
in lining the interior of the said tyre with a viscous and plastic material, the object
being to automatically seal and close small holes or punctures as they are made and
so retain the pressure within the tyre.
I attain this end by lining the interior surface of the air tube, or the tyre itself
if it is a solid wall tyre, with any suitable viscous and plastic material. This lining
may extend either wholly or partially round the interior surface of the air tube or
tyre; and it is retained in position and prevented from flowing by forming on the

page_text: interior surface of the air-tube or tyre, or in a lining adapted to be placed therein,
small projections or ridges, or by mixing with the said viscous and plastic material
short threads of cotton waste or other fibrous material, or by both these means in
combination. As a modification the viscous and plastic material may be interposed
between the layers of material of which a pneumatic tyre is formed.
I do not limit myself to the use of any particular material or substance for lining
the tube or tyre as any material or substance which will remain permanently, or
approximately permanently, viscous and plastic will answer the purpose. The
most suitable material that I am yet acquainted with is an extraction of the bark
of the holly. To this I sometimes add very fine shreds of rubber cut into very
short lengths. I find that the incorporation of the rubber has the two-fold effect of
preventing the flow of the lining material when the tyre is standing in one
position for any length of time, and also of promoting quick regelation after
puncture.
In the event of the tyre being punctured the viscous and plastic material will
automatically close up the puncture and form an effective shield over the hole. In
addition to this action a minute quantity of the material may pass into the hole and
thus plug it or cement the divided edges together.
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 :-
1st. Lining the interior of the air-chamber or chambers of a pneumatic or air-
inflated tyre with a viscous and plastic material, as and for the purpose set
forth.
2nd. In a pneumatic or air-inflated tyre, a lining of any suitable viscous or
plastic material either wholly or partially surrounding the interior surface or any
part of the said tyre, as and for the purpose set forth.
3rd. In a pneumatic or air-inflated tyre the combination with the air-tube of a
viscous and plastic lining thereto, as and for the purpose set forth..
Dated this 8th day of February 1892
ROBT. ED. PHILLIPS, M.I.M.E.,
Consulting Engineer and Patent Agent,
70, Chancery Lane, London, W.C., Agent for the Applicant.