Improvements in or relating to Tyres for Wheels.
Year: 1898

page_text: Date of Application, 4th May, 1898
Complete Specification. Left, 4th Mar., 1899-Accepted, 15th Apr., 1899
Improvements in or relating to Tyres for Wheels.
I, CHARLES KINGSTON WELCH, of Park House, Coventry, in the County of
Warwick, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the tread portion or bearing surface of wheel-tyres,
and more particularly of pneumatic tyres; and it has for its object to provide a
tread surface that shall be less liable than heretofore to slip or skid," in any
direction.
It has heretofore been usual, in order to prevent the slipping or skidding of a
tyre, to provide projections or ridges on its periphery. These projections have
sometimes been arranged circumferentially, that is to say, continuously around
the wheel tyre; and sometimes transversely; and sometimes in an inclined direc-
tion. It has been found however that these projections will only prevent slipping
in a direction at or about right angles to their edges or surfaces. The circum-
ferential projections, while preventing or minimising side slip, do not prevent
circumferential slip; while the transversely arranged projections are very ineffi-
cient for preventing side slip.
According to my invention, I form two series of projections or depressions, one
of such series being intended to prevent slip in one direction and the other in a
direction at or about right angles thereto; the said two series being, in some
instances, at different depths in the material of the tyre or cover.
For example, according to one construction I combine with any of the ordinary
forms of moulded tread surfaces, two or more circumferential projections or ridges,
such projections being arranged on each side of such tread surface, or a central.
ridge or projection. Or I may provide the tread surface of a tyre with two or
more circumferential projections, or ridges, having a wearing or tread surface
or surfaces knurled or otherwise serrated or roughened.
"
Or I may form a knurled or serrated wearing surface on any existing or suitable
form of moulded tread. For instance, the undulating circumferential bars or
ridges of the Welch "
" tread may be so knurled or
or the Dunlop-Welch
serrated; or I may form a tread surface having its central portion provided with
Dunlop-Welch" tyre-
undulating bars or ridges similar to the "Welch" or
tread, but preferably with smaller undulations, and having its sides provided with
one or more longitudinal ribs or continuous projections which may or may not be
knurled or serrated. Instead of providing the central portion of the tread with
undulating bars, I may form in it inclined grooves or projections arranged to
cross each other.
In some instances (especially for motor cars) I prefer to arrange the knurled
projections in a diagonal direction on the tread portion of the tyre, the arrange-
ment being such that, when running on the sloping surface of a crowned road,
the tendency of the tyre to slip down the said surface will be obviated.
I may produce these knurled or serrated surfaces of the tyre by means of corre-
sponding surfaces formed upon the moulds or other apparatus employed in forming
.

page_text: tool.
the tyre, these surfaces of the mould being produced by a knurling or other suitable
Obviously these knurled or serrated surfaces may be combined with longitudinal
or diagonal projections or ridges of square, triangular, curved or any other shape
in cross section.
That 11 J...
1000
I, CHARLES KINGSTON WELCH, of Park House, Coventry, in the County of
Warwick, 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:-
This invention relates to the tread portion or bearing surface of wheel-tyres,
and has reference more particularly to tyres of the pneumatic kind..
"
The chief object of my invention is to provide a tread surface that shall be less
liable than heretofore to slip or skid in any direction. A further feature of
my invention has reference to the moulds in which the said tyres are made.
It has been usual, in order to prevent the aforesaid slip or skid, to provide
projections or ridges on the periphery of the tyre. These projections have some-
times been arranged circumferentially, that is to say, continuously around the
tyre; sometimes transversely, and sometimes in an inclined direction. It has
been found however that these projections will only prevent slipping in a direction
at or about right angles to them; that is to say the circumferential projections,
although preventing or minimising side slip, do not prevent circumferential slip;
while the transversely arranged projections are very inefficient for preventing
side slip.
I therefore provide a tyre or tyre cover with two series of projections or depres-
sions, one of such series being intended to prevent slip in a lateral or sidewise
direction with respect to the tyre, and the other to prevent slip in a circumferential
direction, the said two series being so disposed relatively to each other that the
series for preventing the circumferential slip will be situated between the series
for preventing side slip. In some cases however the series of projections for pre-
venting circumferential slip, instead of being disposed between the series of
projections for preventing side slip, may be disposed upon or directly combined
with the latter series as hereinafter explained.
In order that my said invention may be clearly understood and readily carried
into effect, I will proceed to describe the same more fully with reference to the
accompanying drawings, which illustrate seven various examples of the manner
in which the aforesaid two series of projections or depressions can be arranged
on the tread surface of a tyre.
:
Figure 1 is a perspective view of a portion of a wheel-rim and tyre provided with
one form of tread surface. Figures 2 and 3 are respectively a plan and a central
vertical section of a portion of the outer cover provided with a tread surface of the
kind shewn in Figure 1.
The remaining figures of the drawings, viz.: Figures, 4 to 15, are views similar
to Figures 2 and 3, and shew modified forms of the tread surface. I wish it to
be understood however that I do not confine myself to these examples only.

page_text: In all these figures, A is the outer cover of the tyre, B the series of projections
for preventing transverse slip, and C the series of projections for preventing
circumferential slip.
In Figures 1 to 3 the series B consists of two plain circumferential ridges of
angular cross section arranged on each side of the series C which in this example
is composed of undulatory ridges disposed side by side in such manner that the
crests of one ridge break joint with the crests of the contiguous ridges.
In Figures 4 and 5 the said circumferential ridges 13 are of semi-circular cross sec-
tion and their surfaces are knurled or otherwise serrated or roughened, the said knurl-
ang being either left-handed or right-handed, or a combination of both. In this
example the surface of the tyre cover between the said series B is a single plain
and slightly curved projection; it may however be otherwise formed as desired.
The knurling of the ridges B prevents the circumferential slip, while the ridges
on which such knurling is formed prevent the lateral or side slip.
In Figures 6 and 7 I have shewn the series B similar in form to that illustrated
in Figures 1 to 3, and the series C composed of numerous projections of diamond
or lozenge pattern. Or the series C may consist of transverse ridges or serrations
as shewn in Figures 8 and 9; or of diagonal ridges, as shewn in Figures 10 and 11,
which may be either right-handed or left-handed or a combination of both. Or
the said series C may comprise rows of projections like ratchet teeth as in
Figures 12 and 13, the projections in one row breaking joint with those in the
contiguous rows in a manner similar to the arrangement illustrated in Figures 1
to 3. Or the said series C may be of the shape shown in Figures 14 and 15.
The character of the two series of projections may be modified in a variety of
other ways without departing from the nature of my invention.
In moulds for use in the manufacture of tyres of the kind illustrated in Figures 4
and 5 I prefer, according to my present invention, to form the knurled intaglio
surface of the mould by employing a tool having a roller or rollers so shaped as to
present a cameo surface similar to the knurled surfaces to be produced on the tread
portion of the tyre.
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-
1. A tyre or tyre cover provided with two series of projections or depressions
disposed relatively to each other substantially as described, one of the said series
being intended to prevent slip in a lateral direction and the other in a circumi-
ferential direction.
2. A tyre or tyre cover in which two or more knurled circumferential projec-
tions or ridges of any appropriate shape in cross section are combined with any
desired form of tread surface for the purposes specified.
3. A mould in which the surface for imparting the knurled appearance to the
tyre tread, is formed by a knurling tool substantially as described.
Dated this 4th day of March 1899
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.