Improvements in or connected with Bicycle Tyres.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in or connected with Bicycle Tyres.
I, CHARLES NEWMAN, of Rundle Street, Adelaide, in the Province of South
Australia, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements connected with bicycle tyres and the like,
the special object of the invention being to provide the outer portion of the tyre
with a band or cover constructed of indiarubber or equivalent thereof of such a
nature as shall not only reduce the liability of puncturing the pneumatic bladder,
but shall also in a great degree prevent the sideslip of the wheels. In order to
achieve this object I form the periphery of my band or cover in a V-shaped ridge,
the sides of the ridge sloping down to meet the rounded sides of the tyre tangen-
tially, each sloping side being quite straight and the under part being rounded
or made concave so as to closely fit the part of the tyre it is intended to cover.
The sides of the body of the material converge towards a point. The said
point constitutes the tread of the tyre. The sides are continued downwards or
away from the point until they are sufficiently wide apart to meet the sides of the
rounded part of the tyre at a true tangent. The under portion of my band or
cover is made hollow or concave, the rounded surface being formed with a radius
equal to that of the ordinary tyre or tyre cover which it is intended to protect.
The strips may be cut with great economy from a corrugated sheet of india-
rubber, the straight sides enabling a series of clear cuts to be made without
wasting the material.
In order to secure the best results from my invention I make the point of contact
between the tangential sides and the rounded part of the tyre at a point from
which a line set at right angles from the tangential sides to the centre of the tyre
would make the contained angle X not more than 45 degrees. By constructing
my band or cover in this manner I find that it affords ample protection to the
pneumatic portion of the tyre and at the same time has a tendency to throw
aside loose metal and the like.
I am aware that very small V-shaped ridges have hitherto been used en pneu-
matic tyres, also that strips of larger size, but having rounded sides have been
applied but I find by experiment that the former have a tendency to indent the
pneumatic bladder, and when compressed by the weight of the rider cause the
uncovered parts of the tyre to be expanded thereby, not only presenting a larger

page_text: surface to the liability of puncture, but also increasing the friction between the
wheel and the track, I find also that the strips having rounded sides, the curved
part or additional material which constitutes. the rounded portion interferes with
the resiliency of the tyre, and moreover such pieces cannot be cut with economy
from sheet rubber.
100%
Improvements in or connected with Bicycle Tyres.
I, CHARLES NEWMAN, of Rundle Street, Adelaide, in the Province of South
Australia, Engineer, 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 certain improvements connected with tyres of bicycles
and the like, the special object of the invention being to provide the outer portion
of the tyre with a band or cover constructed of indiarubber or equivalent thereof
of such a nature as shall not only reduce the liability of puncturing the pneumatic
bladder, but shall also in a great degree prevent the side-slip of the wheels. In
order to achieve this object I form the periphery or tread of my band or cover
in a V-shaped ridge, the sides of the ridge sloping down to meet the rounded
sides of the tyre tangentially, each sloping side being quite straight, and the
under part being rounded or made concave so as to closely fit the part of the tyre
it is intended to cover.
In order that my invention may be clearly understood I will now proceed to
describe the same in detail, having reference to the accompanying illustrative
drawings, wherein
Fig. is a front elevation of my invention as applied to an ordinary bicycle.
Figs. 2 and 3, sections of the band or cover on an enlarged scale.
Fig. 4 illustrates the method of cutting out a number of bands from a
corrugated sheet of indiarubber without waste.
Similar letters of reference are used to denote corresponding parts wherever
they occur in the drawings.
A is the body of the material, from which the band is so formed that the
sides BB converge towards the point C. The said point constitutes the tread of
the tyre. The sides BB are continued downwards or away from the point C
until they are sufficiently wide apart to meet the sides of the rounded part of the
tyre at a true tangent, a slight thickness of material being left so as to assist
adhesion. The under portion of my band or cover is made hollow or concave
at D, the rounded surface being formed with a radius equal to that of the ordinary
tyre or tyre cover which it is intended to protect, such tyre being indicated by
the dotted lines at E.
In order to secure the best results from my invention I make the nearest point
of contact between the tangential sides and the rounded part of the tyre in such
a position that a line set at right angles from the said nearest point of contact
of such tangential sides to the centre of the tyre, would make the contained angle X
not more than 45 degrees with the horizon. By constructing my band or cover
in this manner I find that it affords ample protection to the pneumatic portion of
the tyre, and at the same time has a tendency to throw aside all loose metal and
the like.
:

page_text: Fig. 3 illustrates a covering strip moulded into the band so that band and cover
may be combined in one piece.
On reference to Fig. 4 it will be seen that the bands may be cut with great
economy from a corrugated sheet of indiarubber, the straight sides enabling a
series of clear cuts to be made without wasting the material.
I am aware that very small V-shaped ridges have hitherto been used on pnea-
matic tyres, also that covers of larger size, but having rounded sides, have been
applied, but I find by experiment that the former have a tendency to indent the
pneumatic bladder, and when compressed by the weight of the rider to cause
the uncovered parts of the tyre to be expanded, thereby not only presenting a
larger surface to the liability of puncture, but also to increase the friction
between the wheel and the track. I find, moveover, that in strips having rounded
sides the curved part or additional material which constitutes the rounded portion
interferes with the resiliency of the tyre, and, moreover, such pieces cannot be cut
with economy from sheet rubber.
Having now particularly described and ascertained the nature of my said.
invention and in what manner the same is to be performed, I declare that what I
claim is:
-
In combination with a tyre for bicycles and the like-
A solid band or strip of indiarubber (or equivalent thereof), such band or strip
being formed with straight sides which converge from the periphery or tread
and meet the sides of the rounded part of the tyre tangentially, the under part
of such band or strip being formed concave so as to fit closely to the tyre or cover,
substantially as described and illustrated, as and for the purposes set forth.
Dated tha nd HAY At Hahmo
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.