An Improved Method and Apparatus for Making Hollow India Rubber Balls.
Year: 1894

page_text: Date of Application, 10th Oct., 1894-Accepted, 10th Nov., 1894
COMPLETE SPECIFICATION.
An Improved Method and Apparatus for Making Hollow India
Rubber Balls.
A communication by EDWARD MEYER, of Hannover, in the Empire of Germany,
Civil Engineer.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6, Bank Street,
Manchester, both in the County of Lancaster and 323 High Holborn in the
County of Middlesex, Civil 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:-
Hollow india-rubber balls have hitherto been produced by machinery by making
india-rubber discs formed semi-spherical to overlap at their edges, and by pressing
them together by means of a pressure applied from the outside towards the inside
of the ball, the adhering joint thus forming a band or cylindrical casing.
The improved method which forms the object of this invention consists in making
the edges of the discs, which latter are formed more or less into half balls, into the
form of a pipe flange and pressing these one upon the other; the adhering edges or
flanges thus form a projecting ring lying in one plane. When pressed together,
the direction of pressure is therefore tangential to the circumference of the ball
and vertical to the plane of the seam. This circumstance affords the advantage
of it being possible to apply an unlimitedly strong pressure, whilst a pressure
directed towards the interior of the ball would naturally find no sufficient
counter-force.
In addition in the older methods of construction the drawback became apparent,
that, more particularly in the case of large balls, folds or creases were formed on
the edges of the half balls, which could only be avoided with difficulty or not at
all. Within the seam there was therefore formed in these balls a thick roll of
india-rubber, which means a waste of material, and which interferes with the
evenness of the ball.
The double flange which is formed in this new method of fastening, and which
projects to the outside, is entirely removed during the vulcanising process by the
inflation of the ball, as it is drawn entirely into the interior of the wall, so that a
perfectly round ball results.
In order to be able to produce this kind of ball by machinery, the invention
further consists of the following arrangement, which is shown in the accompanying
drawings in which
Figures 1 and 2 are sectional elevations of the apparatus with the matrices open
and closed respectively.
In Figure 1, a b are two matrices or moulds for forming half balls from discs,
which are placed flat on the edge of the lower mould or matrix and on the holder c
arranged for the purpose. Both matrices or moulds are connected with a vacuum
pipe d, and by opening the cock d' such an action takes place that both india-rubber
discs are drawn into their respective moulds. The edges of these moulds are formed
to act as supports for the narrow end strips of the half balls which are to form the
flanges.
After the half balls have thus been shaped, the holder c is removed and the one
matrix or mould is approached to the other. In the drawing for instance, the lower
one is approached to the upper one, and this takes place by means of the same
vacuum, causing a pressure of the atmospheric air on the piston f (see Figure 2).
(Prins eri

page_text: The tubes g and are separated by the upward movement of the lower matrix so
that atmospheric air enters into both of them, which again releases from the walls
of the moulds the two half balls which have been pressed therein.
When the flanges of the two half balls resting on one another have been
Bufficiently thoroughly connected by means of the strong pressure of the press, the
vacuum pipe e is closed, and the air supply pipe i is opened so that the lower mould
descends by its own weight. The ball may then be removed and treated in the
usual manner (vulcanised) during which process as already stated the projecting
flanges or flange edges are themselves drawn into the wall or in other words,
entirely disappear.
Having now particularly described and ascertained the nature of the said inven
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent I declare that what I claim is:-
1. An improved method of making hollow india-rubber balls consisting in forming
flange like edges on the india-rubber discs employed for constructing the balls and
pressing them together so that their adhering surfaces lie in one plane, substantially
as described.
2. An improved method of forming domed india-rubber discs or half balls
consisting in placing the discs which are to be shaped upon a mould or matrix and
producing in the latter a vacuum so that the india-rubber disc is forced against the
walls of the mould by means of the pressure of the outside air, substantially as
described.
3. An improved apparatus for carrying out the process described in Claims 1
and 2, consisting in moulds or matrices connected with a vacuum apparatus and
adapted to be pressed together by means of an air piston operated also by the
vacuum, substantially as described and illustrated.
Dated this 9th day of October 1894.
WM. P. THOMPSON & Co.
Agents.