Improvements in the Manufacture of Glass Articles.
Year: 1899

page_text: Date of Application, 25th May, 1899
Complete Specification Left, 17th Oct., 1899-Accepted, 2nd Dec.,
1899
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Glass Articles.
I, PAUL THEODOR SIEVERT, of 43, Eisenstuckstrasse, Dresden, in the Empire of
Germany, Glass Manufacturer, do hereby declare the nature of this invention
be as follows:-
The process of manufacturing hollow glass bodies according to my Patent
Application No. 2094 of January 30th 1899, is characterised by this, that a
layer of glass is spread out on a perforated plate, and is exposed, in its plastic
condition, to the action of a supplied or introduced pressure medium, in order to
be formed by shape-giving frames or moulds, into hollow glass bodies.
In the further development of my invention, I have found that the introduc-
tion or the supply of a pressure medium from outside is not necessary in all
cases for the formation of the hollow glass bodies; I have found that the gene-
ration of such pressure medium may be effected by the heat of the molten or
plastic glass.
This generation of such pressure medium may, in a most suitable manner, be
effected by a moist, porous mat, which is put upon a suitable support, and upon
which mat the flat plastic glass layer is put.
The generation of a pressure medium is thus effected in a similar manner to
that described in my Application No. 28384 of Feb. 8, 1899, for shaping articles,
such as letters, stamped out of a plastic mass of glass, convex above and concave
below.
The porous mat, which may be made of fibrous material, asbestos, textile fibre
made incombustible, or such-like suitable material, may be put on its support in
a moist state for each operation, or it may be moistened by introducing water
into the hollow space of the support.
From the contact of the hot glass and of the moist mat, steam pressure is
generated.
The regulation of such pressure for suitably blowing out the flat plastic glass
between a shaping frame, or into a mould, is effected by more or less pressure
exerted by said frame or mould upon or into the plastic layer of glass, or upon or
into the moist mat.
The regulation of the pressure may be effected by the hand of the workman, or
by mechanical means.
531
1
1000

page_text: Improvements in the Manufacture of Glass Articles.
I, PAUL THEODOR SIEVERT, of 43, Eisenstuckstrasse, Dresden, in the Empire of
Germany, Glass Manufacturer, 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:-
The process of manufacturing hollow glass bodies according to my Patent
Application No. 2094 of January 30th 1899, is characterised by this, viz., that a
layer of glass is spread out on a perforated plate, and is exposed, in its plastic
condition, to the action of a supplied or introduced pressure-medium, in order to
be formed, by shape-giving frames or moulds, into hollow glass bodies.
In the further development of my invention, I have found that the introduc-
tion, or the supply of a pressure medium from outside, is not necessary in all
cases for the formation of the hollow glass bodies: I have found that the gene-
ation of such pressure medium may be effected by the heat of the molten or
plastic glass.
This generation of such pressure medium may, in a most suitable manner, be
effected by a moist porus mat, which is put upon a suitable support, and upon
which mat the flat plastic glass layer is spread.
The generation of a pressure medium is thus effected in a similar manner to
that described in my application No. 2834 of Feb. 8th, 1899, for shaping articles,
such as letters, stamped out of a plastic mass of glass, convex above and concave
below.
The porous mat, which will consist of fibrous material, asbestos, textile fibre,
made incombustible, or such-like suitable material, may be put on its support in
a moist state of each operation, or it may be moistened by introducing water
into the hollow space of the support.
From the contact of the hot glass with the moist mat, steam pressure is
generated sufficient to convert the glass into a hollow vessel, which will take
the contour either of a shaping frame or of an overlying mould.
In the accompanying drawings, both these plans of shaping articles of hollow
glass are illustrated.
In Fig. 1, is a solid slab, supporting a mat m of asbestos, upon which lies
a sheet of molten or plastic glass e. Overlying this, is a shaping frame f, which
is caused to nip the glass tightly upon the mat by means of clamps n, n, which
grip the frame f and slab a.
The mat, before receiving the molten glass, is moistened with water, and the
heat of the glass. when laid on the mat, will quickly generate steam, the pres-
sure of which, as it augments, will blow up the glass, as indicated at e¹, thereby
producing a howl which will have a flat flange at its lin. Any roughness or
irregularity at the edge of this flange may be removed by grinding and polishing.
Fig. 2 shows a modification of the apparatus for shaping hollow glass articles.
In this case, the supporting slab a is hollow, and pierced with holes a¹, to allow
of water supplied to the underside thereof, under pressure, by the pipe b (and
withdrawn therefrom by the pipe ), to percolate upwards, and saturate the
porous mat of asbestos or other suitable material m. Overlying this mat is a
mould g, which is held down upon the glass by a frame f connected by screw
clamps with the slab a.
As steam is generated by the contact of the hot glass with the moistened
mat m. the glass will he forced upwards, as shown at 1, and caused to fill the
mould g. To ensure this filling of the mould, it will be requisite to increase
the pressure of the steam below the glass. This may be done by tightening the

page_text: screw clamps gradually, and thus the glass will be caused to rise, as the clamping
pressure is increased, in the manner indicated by the dotted lines in Fig. 3,
which show successive stages of the moulding or expansion of the glass.
Although I have mentioned the use of screw clamps for regulating the pressure.
I wish it to be understood that I do not confine myself to this means, as the
pressure may be applied by the hand of the skilled workman, or obtained by
the employment of excentrics, or by any other suitable mechanical means, the
object being, as before stated, so to regulate the pressure of the expanding
medium, as to ensure the blowing up of the flat plastic glass through a shaping
frame or into a mould, to produce a vessel of the shape and capacity desired.
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;-
The manufacture of hollow articles of glass from a plastic layer of glass placed
on, or overlying, a moistened bed of asbestos, or equivalent absorbent material,
capable of evolving, under the action of the heated glass, an elastic pressure
medium, which, by the aid of a shaping frame or mould, will form the article
desired to be produced, the pressure of such elastic medium being controlled
or regulated by the shaping frame or mould, as above set forth.
Dated this 16th day of October 1899.
NEWTON & SON,
Agents for the Applicant.