Improved Manufacture of Compound Glass and Metal Plates or Articles.
Year: 1899

page_text: Date of Application, 9th Jan., 1899-Accepted, 9th Jan., 1900
COMPLETE SPECIFICATION.
Improved Manufacture of Compound Glass and Metal Plates or
Articles.
2.4
I, PAUL THEODOR SIEVERT, 43, Eisenstuckstrasse, Dresden, in the Empire
or Germany, 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:―
This invention relates to the manufacture of glass plates or other articles of
glass covered or combined with metal.
In the manufacture of acid-proof vessels, and the like, of special size, which
cannot be manufactured in one piece, and, therefore, are made by joining several
glass plates or parts together it is very difficult to make the joints perfectly water-
tight. It is, therefore, of great advantage to be able to cover the glass plates
with a coating of acid-proof metal, such as for instance, lead, and then to unite
the several metal-coated glass plates by soldering or any similar process; the
lead-coat serving moreover as a protection to the glass plates.
To attain this object according to this invention, i.e., to procure a perfect
mechanical union between the glass-plate and the metal, the glass plate is heated,
covered with a cold sheet of lead, or any other suitable metal, and this compound
plate is then well rolled. Owing to the heated glass plate coming into sudden
contact with the cold metal a number of hair-rents or surface cracks are formed
in the former into which the lead, on the point of melting on account of its
contact with the hot glass plate, enters, as soon as the two sheets are exposed
to pressure by rolling. A still better effect is obtained when those cracks necessary
for the adhesion of the lead are produced in an artificial manner before being
heated, by coating them with hot glue, as in the case of the production of the
so-called ice-flower-glasses. These cracks expand under the subsequent heat, and,
on cooling contract to such an extent as to take a. good grip on the metal.
After cooling the lead covering will be found to adhere intimately to the glass-
plate. In order to augment the security of the adhesion the glass-plates on being
cast may be provided with grooves, conical or other holes, or projections or
depressions into which the metal is pressed; and the holes or grooves being
smaller at the surface the metal is held firmly after cooling.
A similar result is obtained when the glass-plates are first provided with ribs
or ridges; here also the upper portion is expanded or flattened out under pressure,
the lead filling in completely the spaces between said ribs as shewn for example
in Figures 4 and 5.
Instead of applying the metal to the glass plate, it is of course possible to
proceed in the reverse manner, which it is especially advisable to do when only
part of the glass plates are to be covered with metal; for in many cases it will
suffice to so cover the glass plates only to a certain distance from the edges etc.
In this case the process should be carried out in a closed vessel, with a view of
excluding the air to prevent oxidization of the metal. Another modification of
the process consists in pouring the molten metal on to the hot glass plate, rolling
and pressing.
A very important modification of the process for covering glass with metal
is the following:-
-
Fluid class is pressed out to form a plate in a cooled press-mould
The se

page_text: through contact with the cold mould is at once converted into granulated or
cracked glass. On this the molten metal is poured, or, preferably, a heated
metal plate is placed; after which while still contained in the press-mould they
are pressed to form a homogeneous mass. The molten metal, or part of the
metal plate, rendered liquid by contact with the heated glass, spreads uniformly
under pressure and enters into all the fissures and interstices formed by the
molecular arrangement of cracked glass, and may even run round the edges
underneath the glass plate, thus enclosing it on all sides. In this manner a
homogeneous connection between the glass and the metal is obtained, the com-
bination showing on all sides a metallic surface, and owing to the form or cracked
condition of the glass it encloses, possessing a certain amount of pliability.
A modification of this process is effected by filling up a cooled press mould
with and pressing into the shape of a plate, a quantity of heated glass fragments
or glass that has been previously granulated or cracked. On to this, molten
metal is poured or still better, a heated metal is applied and the combination
exposed to pressure in the cooled press-mould as before described
The degree
of pliability and plasticity of these plates increases in accordance with the
smallness or number of the cracks or fragments of glass employed. Thus it is,
for instance possible to produce very thin compound plates, by subjecting the
stouter plates as they come from the cooled press-moulds, to repeated pressure by
rolling; which additional pressure also tends to increase the density of the com-
pound plate.
Such metal-coated glass plates will serve many other purposes besides those
mentioned at the beginning of this description, as, for instance, for accumulator
vessels, electro-plating vessels and the like, where the insulation by glass of
metallic conductors is of great importance.
It should also be remarked that this process is not limited to the production of
flat combination-plates. It is possible, also, to produce, thereby, figured plates,
bent plates or articles of other form.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:
1. The manufacture of metal-coated glass plates or articles by uniting heated
glass with molten metal, or with metal which becomes fused by the heat of the
glass and by pressing such compound body between cooled surfaces; the glass
being provided with grooves or ridges or fissures or like means for ensuring an
intimate engagement between it and the metal, substantially as described.
2. A modification of the process described in Claim 1 consisting in granulating
the heated glass in a cooled press mould and uniting it mechanically with a
covering of metal by pressure; the thickness of the combination plate being
reduced if desired, and its density increased by further pressure substantially
as described.
3. A modification of the process described consisting in the employment of
small pieces of glass, which after being heated and covered with the heated metal
are subjected to pressure, whereby combination plates or articles are produced
the thickness of which may be decreased, and their density increased by again
subjecting them to pressure by rolling substantially as described.
4. Compound glass and metal plates or articles manufactured substantially in
the manner described.
Dated this 9th day of January 1899.
15.
BOULT & WADE,
Agents for the Applicant.