Improvements relating to Pneumatic Tyres for the Wheels of Cycles and other Vehicles.
Year: 1893

page_text: Date of Application, 21st Feb., 1893
Complete Specification Left, 28th Oct., 1893-Accepted, 2nd Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements relating to Pneumatic Tyres for the Wheels of Cycles
and other Vehicles.
I, WILLIAM ERSKINE BARTLETT, of 21 Buckingham Terrace, Edinburgh,
India Rubber Manufacturer, do hereby declare the nature of this invention to be as
follows:-
Pneumatic tyres ordinarily consist of three parts, the air tube, the metal rim and
the cover for protecting the air tube and securing it to the rim.
My present improvements relate to the metal rims and air tube covers
particularly to those covers which are held to the rims by the pressure of the
air in the air tubes. I now form the metal rims and the covers so that the edges
of the rims shall rest or be embedded in recesses formed in the cover.
By this
means the outsides of the edges of the metal rims will be surrounded by the cover
and the contour of the whole tyre will be continuous and therefore free from any
hollows into which mud and dust can be deposited.
The metal rims have their edges bent inwards and the side edges of the cover
are made to fit to the interior of the rim one to one half on one side of the rim and
the other to the other half so that they may be securely held by the pressure of air
in the air tube when the air tube is inflated.
The covers are moulded in the usual way, they may be moulded flat but I prefer
to make them in moulds of a curvature in cross section approaching that of the
tyre in use.
Dated this 21st day of February 1893.
CARPMAEL & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to Pneumatic Tyres for the Wheels of Cycles
and other Vehicles.
I, WILLIAM ERSKINE BARTLETT, of 21 Buckingham Terrace, Edinburgh,
India Rubber Manufacturer, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
My invention relates to pneumatic tyres for the wheels of cycles and other
vehicles and more especially to that description of tyre in which the cover of the
tyre is maintained in position on the rim by the pressure of the air in the air-tube
of the tyre. The object of my said invention is to provide an improved cover for
holding the air-tube to the rim, and to so fit the same to the rim that there shall be
no hollows or recesses in the tyre wherein mud and dust can collect.
According to my invention I make the metal rim with its edges bent inwards
towards each other on that side of the rim which is remote from the hub of the
wheel. I form the cover with a thickened portion near each edge but having a
groove extending along said thickened portion. When the tyre is fitted to the rim
the turned-in edges of the rim lic snugly in the grooves provided in the cover.
The innermost parts of the edges of the cover fill the space between the turned-in
edges of the rim and are securely held therein by the pressure of the air in the air-
tube of the tyre. The outer portions of the edges of the cover surround and closely
fit against the edges of the rim.

page_text: "
The accompanying drawing is a transverse section shewing a pneumatic tyre
fitted to a rim in accordance with my invention.
A is the rim, B is the air-tube of the tyre, and C is the cover which forms the
tread portion of the tyre.
The edges A' of the rim are bent towards each other as shewn, and are preferably
formed with a bead A' to prevent any damage to the tyre cover when the tyre is
secured in place on the rim. I prefer to make the middle portion of the rim to
which the spokes are attached of thicker metal than the edges thereof as shewn
at A but this is not essential to the carrying out of my invention.
The cover C is thickened near its edges as shewn at C¹ and is provided with a
groove extending along the said thickened portion in which groove the edges A¹ of
the rim are embedded. The parts C' of the cover together fill the space between
the turned-in edges of the rim and are maintained in that position when the tyre is
in use by the pressure of the air in the air-tube of the tyre. The outer parts C³ of
the cover surround the edges of the rim as shewn thereby filling the angular groove
which is usually formed between the edges of the rim and the tyre cover.
tyre will thus be free from any hollows or recesses in which mud and dust can
collect.
The
The covers are moulded in the usual manner and I prefer to use moulds which
are curved in the direction of their length so as to avoid the difficulty experienced
in fitting straight covers to the rim.
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 :-
A pneumatic tyre the outer cover of which is thickened at or near its edges and
has in the thickened portions grooves or recesses in which the edges of the rim are
.embedded when the tyre is in its place on the wheel, substantially as, and for the
purpose, specified.
Dated this coth way of October 13.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.