New or Improved Method of and Apparatus for the Manufacture of Glass Plates, Cylinders, Pipes, and certain other Bodies.
Year: 1891

page_text: Date of Application, 24th N v., 1891-Accepted, 24th Dec., 189;
New or Improved Method of and Apparatus for the Manufacture of
Glass Plates, Cylinders, Pipes, and certain other Bodies.
A communication by ROGER SHERMAN PEASE, of Minneapolis, in the County of
Hennepin and State of Minnesota, United States of America.
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 :-
This invention relates to a method of and apparatus for the manufacture of
glass plates, cylinders, pipes and other bodies, as hereinafter more fully set
forth.
In the accompanying drawings:
Figure 1 is a longitudinal vertical section through this apparatus showing the
tanks as arranged to be heated by regenerative furnaces of the well known Siemens
type, which arrangement is adopted in the drawings merely for purposes of illus-
tration, and not as indicating a necessary construction;
Figure 2, a sectional view of the portion to which the invention more particularly
relates, drawn upon a somewhat larger scale;
Figure 3, a perspective view partly in section, illustrating the action of the
apparatus as applied to the formation of cylindrical bodies;
Figure 4, a similar view showing the arrangement as applied to the formation of
a rectangular body;
Figure 5, a perspective view showing means for cooling the glass as it is drawn
or formed into sheets; and
Figure 6, a perspective view of the bait employed in the formation of flat sheets
or rectangular bodies.
The principal novelty in the present invention is that of forming sheets, hollow
cylinders, or other hollow bodies by dropping or dipping into a mass of molten
glass or metal, the lower edge of a bait, advisably of glass, and causing the
molten metal to adhere to the edge of the bait and to be drawn upward with
the latter, the thickness of the edge of the bait, the consistency of the metal, and
the rate of upward movement determining the thickness of the sheet, cylinder or
body produced.
This thickness may be further determined and its uniformity maintained by the
aid of cooling devices adapted to act upon the glass just above the level of the
molten mass, and to chill or cool the sheet or body drawn therefrom, and some
device of this sort will be ordinarily required, particularly where the glass is to be
of any considerable thickness.
Sheets and plates may be manufactured in either of two ways, that is to say,
either by forming first a hollow cylinder, and subsequently cutting off the ends and
splitting the cylinder in the direction of its axis, then flattening the sheet as is done
in the manufacture of window glass at the present time; or two flat sheets may be
produced each attached at its upper end to the bait, and severed from the bait
before the sheets are annealed.
The latter plan is preferred where it is desired to produce large or heavy
sheets of thick glass, but for lighter glass the formation of a cylinder is
preferred.
The same method is applicable to the formation of hollow bodies of any

page_text: desired cross section, rectangular, cylindrical or polygonal, the form of the bait
being varied according to the desired formation of the body to be produced.
Referring now to the drawings,
A and B represent two tanks designed to contain molten glass, which may be
produced therein or delivered thereto from other smelting furnaces, and merely
kept at the proper consistency in said tanks.
In practice, however, it is preferred to reduce the batch in said tanks, and for
that purpose the regenerative apparatus, C and D', is provided, which, being well
known and not constituting a part of the present invention, need not be further
described herein.
The tanks A and B will be made of dimensions appropriate to the character
of the work to be performed, and to the desired capacity of the apparatus.
In practice, it is deemed desirable to construct the bottom of the tanks of fire
brick or clay, sustained by a metal backing or bottom, the whole carried upon
suitable columns and girders so as to leave free space beneath the tanks for the
passage of the workman and for the mechanical appliances used in the operation of
drawing or forming the sheets or bodies.
The arching walls or tops of the furnaces extending over the tanks A and B are
carried downward to the bottoms of the tanks and across the same from side to
side with the exception of suitable openings a at or near the bottoms of the tanks
for the passage of the finer and heavier glass into extensions A and B of the tanks
outside of the walls .
The flow of glass from the tanks A and B to their outer extensions A' and B¹
is controlled by sliding gates C, which are advisably made of iron and formed with
an internal space or opening through which water or other cooling medium is
caused to pass in order to protect the gates against the extreme heat to which they
are subjected by being brought into contact with the molten glass.
The gates are raised and lowered by means of screws D, provided with hand
wheels, or in any other convenient manner.
When drawn down, the upper ends of the gates C are flush with the bottom of
the tanks A B, and the metal flows freely and smoothly along the bottom of the
tanks beneath the walls, and upwardly into the tank extensions A and B³,
bringing the metal to a uniform level in the tank and tank extensions.
It is designed to work the apparatus continuously, and to supply additional
materials to the tanks or to the smelting furnaces which supply the tanks, in
proper quantity to maintain a substantially uniform level in the tanks A and B, at
all times.
The tank extensions A¹ and B' may be entirely separate, or they may be
connected as indicated in Figure 3, the latter construction being necessary for
the formation of cylinders and other continuous bodies, while the separated or
disconnected tank extensions will be found preferable for the formation of
sheets.
E indicates a vertically movable plunger, which is advisably made hollow,
and cooled by means of a spray of water, a current of air, or other suitable cooling
medium to prevent its being warped or injured by the heat to which it is subjected.
and enable it to cool or chill the glass which is raised about it, as will be further
explained later on.
This plunger may be raised and lowered in any convenient manner, as, for
instance, by means of a cable F passing from a fixed support on one side of the
plunger and above its lower end, downward to and about a pulley at the lower end
of the plunger, thence upward and over another pulley located on the side of the
plunger opposite the support to which the end of the cable is made fast, and finally
to a winding drum C.
This arrangement gives adequate power and a steady movement to the plunger
which is also guided in any suitable manner to ensure a perfectly uniform and
regular movement.
The plunger is designed to play through an opening in or between the tank

page_text: extensions A and B', with sufficient space between the walls of the opening and
the sides to form a free passage for air, and, in order that the plunger may not be
unduly heated, the walls of the tank extensions, facing the plunger, are inclined
away from the plunger, as shown in Figures 1, 2, 4 and 5.
The glass which Hows into the tank extensions A' and B' is subjected to the
cooling influence of the atmosphere, and is thereby brought to the proper con-
sistency for working, but, to prevent undue or too rapid cooling of the glass thus
exposed, guards or covers H may be used, as shown in Figure 1, which will be
hinged at their lower edges to the walls b, b, and arranged to swing to the required
position.
These guards or covers may also be made to perform an additional function in
cooling or severing the glass just as it begins to be drawn from the mass in the
tank extensions, so as to prevent its being drawn out too thin, a provision which
will be further explained in connection with Figure 5.
As shown in Figures 1, 2, 3, 4 and 5, the walls of the tank extensions nearest
the plunger are made comparatively thin, and are carried upward above the body
or lining of fire brick, and, if found necessary, may be made hollow and cooled by
the passage of water, air or other fluid through them.
The plunger E, in whatever form it may be made, and whether hollow or solid,
as it may be in some cases, is spread out at the top, as best shown in Figures 3
and 4, the enlargement being formed by means of a removable cap or top piece I,
of a form depending upon the character of the work to be done.
Referring now to Figures 1, 2 and 3, which represent the apparatus arranged for
the making of a hollow glass cylinder, the plunger E is represented as formed or
provided with a circular cap I, which is designed to support a circular bait J,
which is formed with a depending flange or lip c.
This lip is designed to project downward far enough to permit it to enter a short
distance from one to two inches, more or less, into the molten metal, when the
plunger is lowered, so as to bring the cap 1 down to the upper edge of the wall or
casing of the tank extension or receptacle containing the molten metal in the
chamber into which the bait dips, or the level to which the bait may be lowered
relatively to the level of the molten metal.
When the metal has been brought to the proper consistency and allowed to flow
in and fill the tank extension, the plunger E is raised to a sufficient height to
permit the head or cap I to be placed thereon, after which the bait is placed over
the cap, and then, as promptly as may be, the plunger is allowed to descend until
the depending edge or flange of the bait dips into the molten metal a distance
sufficient to cause a partial fusion of said edge, and its union with the metal of the
tank, so that, upon reversing the motion of the plunger and lifting the bait, the
molten metal will be raised and caused to follow the bait.
As above stated, the plunger is cooled by water or other cooling medium from
within, and the air which passes upward around the plunger is cooled by contact
with said plunger, and, consequently, chills the inner surface of the film or sheet
drawn upward by or with the bait.
Care should be taken to see that, previous to causing the bait to descend to and
enter the molten metal, the latter be allowed to cool sufficiently to give it the
proper consistency to ensure the drawing out of the film to a proper thickness, as it
will be readily understood that, if the metal be in a too fluid condition, the film or
sheet will be very thin and may break in drawing, but the cooling action of the
plunger within and of the atmosphere without ensures a quite prompt cooling and
hardening of the film or sheet, so that, with reasonably careful management and
with proper speeding of the plunger in its rising movement, the thickness of the
film may be nicely determined and maintained.
As shown in Figures 1, 2 and 3, the bait J, when used for cylindrical or
polygonal bodies, is formed with a knob or boss d, which is designed to be clasped
or engaged by a crab or clamping device K, which is suspended by a chain or

page_text: "
cable L from a pulley swivelled in a truck or car M, which runs upon a suitable
track at the top of the building, or at a suitable elevation above the tanks.
The purpose of this apparatus is to complete the drawing operation begun by
the plunger, the latter being raised ordinarily only to such a height as is necessary
to begin the drawing operation and determine the thickness of the film or sheet to
be produced, without which the plunger remains thus elevated and continues to act
as a cooler for the interior of the glass body as the latter is drawn up by the chain
or cable and clamping devices.
When drawn out to the desired length, the cylinder, film or sheet is cut or
severed and allowed to rise freely without further drawing up metal from the tank
or containing receptacle, and the body thus drawn or formed is carried away by
the truck M to the annealing oven, or to such other point as may be desired.
While the drawing operation has been described as being performed partly by
the plunger and partly by other means, it is to be understood that it may be
entirely performed by either of said means alone, that is to say, the plunger may
rise to a height sufficient to fully complete the drawing, or the bait may be lowered
and again elevated to the required height by the chain or cable L without the aid
of the plunger.
Mr. Pease finds, however, that the conjoint action of the two is better calculated
to produce the results desired, and, therefore, prefers to make use of the two
appliances.
It is important to be able to cool the molten metal to a greater or less degree
according to its consistency and other controlling circumstance or conditions, in
order that the thickness of the film or sheet may be accurately gauged and varied
from time to time if desired.
It is therefore proposed, in some cases, to make the metal facing or binding of
the tank extensions hollow, and to provide the same with outwardly turned lips or
flanges g, Figure 5, which project to such distance as will cause them to touch or
nearly touch the film as the latter is drawn up from the molten metal, thus chilling
or cooling the inner face of said film almost at the instant of its formation, giving
to the same a solidity or consistency sufficient to ensure the retention of its shape
and thickness. Said result may be further ensured by combining, with said cooling
lips g, or by using independently thereof, coolers H, which may be either solid
plates or bodies of metal arranged to be drawn against or into close proximity
with the film at a point near its commencement; or hollow metallic bodies cooled
by water or other fluid passing through them and supplied from any convenient
source.
The coolers H may also be made to act as covers to retain the heat of the
molten metal in the tank extensions, but, when used exclusively for that purpose, it
is preferred to hinge them to swing upward as shown in Figure 1, instead of
swinging downward below the level of their hinges as shown in Figure 5.
By employing the cooling lips or flanges and the cooling plates H, and
furnishing the latter with means for promptly raising and lowering them, the
plates H may also be made to serve the purpose of severing the sheet or film from
the metal of the tank or hollow extension.
Referring to Figure 5, it will be seen that, as the coolers H are elevated, their
free or outer edges press the glass film against the cooling lips or edges, and, if
the movement be made quick, it will serve to effectually squeeze or press the glass
between said edges and effect a severance thereof.
Levers N or other suitable means may be provided for actuating the coolers H,
suitable locking devices being provided to hold the levers and, consequently, the
coolers at any desired adjustment. The same arrangement for this purpose is
represented in Figure 5, but, obviously, this may be considerably varied without
departing from the spirit of this invention.
In Figure 4, the plunger E is represented as extending at its edges to the end
walls of the tank extensions A and B¹, so that no metal is permitted to enter

page_text: between the edges of the plunger and the walls of the tank; hence it will be seen
that, if the plunger rise, it will draw up two films or sheets, each disconnected from
the other, except as they are joined at their upper ends by the bait J.
Said figure also shows the cap or head in a form suited for the formation of
flat plates or sheets, that is to say, in the form of an elongated bar with a rounded
or semicircular upper face, and with ribs or flanges to fit down over the seats of the
plunger and retain the head in position thereon.
The ends of the cap or head are provided with lugs or gudgeons to receive the
hooks or fastenings by which connection is made with the lifting chain or
cable.
In Figure 6, the bait is represented in a form suitable for use in connection
with the cap or bar and plunger shown in Figures 4 and 5, that is to say, a bait
curved to conform to the curvature of the upper surface of the cap or head I, and
with sides depending to a sufficient distance to ensure the entrance of the edges
into the molten metal when the plunger E is lowered to a proper level.
This bait may be conveniently formed of a sheet of glass of proper size by
simply placing the same over a block containing a recess of the desired contour of
the bait, and subjecting the plate to a sufficient dégree of heat to cause it to sag
and to rest upon the inner surface of the recess, but, obviously, the particular
manner of shaping the bait is not important, and may be varied at will.
It has been proposed heretofore to produce a sheet of glass by dipping an iron
bar into the molten metal, and then raising the bar; but, so far as Mr. Pease is
aware, no one has ever practically succeeded in producing sheets of glass in this
way on a commercial scale, although the idea was long since proposed and
elaborately described.
The difficulty has been due to the fact that the rate of construction and expansion
of glass and iron differ widely, and that the glass is liable to be cracked or checked
in consequence thereof before it can be detached from the bait, or severed from the
portion adhering thereto.
By employing a glass bait, these difficulties are completely obviated, it being
well known to all familiar with glass working, that, if a piece of glass be dipped
into molten metal, a fusion soon occurs which joins one to the other, and, if the
inserted glass be not too long subjected to the intense heat of the metal, or if it
be promptly raised, it will be found that the molten metal will follow after it and
will be drawn out to a uniform thickness.
It will be readily understood that the details of the apparatus may be considerably
varied without departing in any manner, from the essential features set forth
herein; thus, other hoisting devices may be substituted for the chain or cable L
and the pulley over which it passes, or for the cable F by which the plunger is
raised and lowered, and levers may be substituted for the screws for raising and
lowering the gates C.
So too, coal or oil-burning furnaces may be substituted for the gas furnaces
and regenerators illustrated, and, in many other particulars, the details may be
varied.
By the employment of the gates C, working outside of the tanks proper, and
falling to a point where their upper ends or edges are just flush with the bottom of
the tanks, so that no part of the metal is caused to pass through an opening in the
bottom of the tank, the rapid wearing away of the tank body is avoided, which
always attends the flow of molten metal through an opening therein, the cooled
plunger serving also to cool the fire brick and thus to increase the protection of
the opening.
A serious obstacle, which has been encountered in attempts to draw the
metal off through a hole or opening in the bottom of the tank, is thus avoided.
It is apparent that a single tank may be employed instead of the two tanks, or
that a series of tanks may be used.
In order to prevent the film or sheet from adhering to the fire-brick walls at the
edges, the metal facings of the tank extensions are provided with outwardly

page_text: turned lips or guards i, Figure 4, against which the edges of the glass are drawn.
Being cooled, these lips or edges serve the triple purpose of cooling or partially
chilling the edges, causing the metal to draw continuously of full width from guard
to guard, and preventing undue adhesion to, or fusion with, the walls of the
receptacle containing the molten metal.
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. The herein described method of forming sheets and films of glass, which
consists in dipping the depending edge of a bait formed of glass into molten metal,
permitting the edge to become partially or wholly fused by the molten metal,
lifting the bait so as to draw up therewith the desired film or sheet.
2. The method of forming glass films or sheets, which consists in inserting the
depending edge of a bait formed of glass into molten metal, permitting said edge
to become partially or wholly fused with the molten metal, then lifting the bait
and thereby drawing upward with it a film of glass from the molten metal, at
the same time subjecting said film to the action of suitable cooling devices or
mediums.
3. In the manufacture of glass films and sheets, the following steps, namely;
first, dipping the depending edge of a bait into molten metal; second, lifting the
bait a distance sufficient to raise with it a film or sheet of the molten metal, at the
same time raising within the body thus elevated a cooler, and subjecting said body
to the cooling action thereof from within, and to the cooling action of the
atmosphere from without, so as to solidify the film, and finally lifting the bait and
the body connected therewith subject to the internal and external cooling action,
substantially as set forth.
4. The herein described apparatus for the manufacture of glass films, sheets and
bodies, consisting of a tank having an extension, a plunger movable upward
through the tank extension, and a bait carried by said plunger and having
a depending lip or Hange to enter the tauk extension, substantially as set forth.
5. In an apparatus for the manufacture of glass films or sheets, a receptacle for
containing molten metal, a plunger movable upward through said receptacle but
protected from the contact of the metal therein, and a bait carried by said plunger
and having a depending flange or lip adapted to extend downward into the molten
metal when the plunger is properly lowered.
6. In combination with a receptacle for containing molten metal, a plunger
movable upward through said receptacle, a bait carried by said plunger, and a
hoisting device above the bait and independent of the plunger, adapted to clasp
and elevate the bait.
7. In combination with a receptacle adapted to contain molten metal, a plunger
movable upward through the same, but protected against contact with its contents,
a bait carried by said plunger, a hoisting device above and independent of the
bait but adapted to grasp the same, and a travelling car carrying said hoist and
serving to convey the bait and the depending film or sheet to the annealing oven
or desired point.
8. In an apparatus for the manufacture of glass, the combination of a tank, as A,
provided with an outlet as a, at or near its bottom, and a vertically movable gate
as C, adapted to move across said outlet from below, substantially as and for the
purpose set forth.
9. In combination with tank A and wall b, outlet a at or near the bottom of the
tank, gates C movable across said outlet from below, and a screw stem D connected
with and serving to move said gate.
10. In an apparatus for the manufacture of glass films, or sheets, the combina-
tion of a suitable receptacle for containing molten metal, a plunger movable
vertically through said receptacle, and a cooling lip g surrounding said plunger
and serving to cool the film carried upward thereby.

page_text: 11. In combination with a receptacle for containing molten metal, and with a
plunger movable vertically through the same, a cooler as H, adapted to act upon
the outer surface of the film raised by the plunger, and to cool the same, substantially
as and for the purpose set forth.
12. In combination with a receptacle for containing molten metal, and with
plunger S movable upward through the same cooling lip g, and cooler H, adapted
respectively to cool the inner and the outer surfaces of the film carried upward by
the plunger.
13. In an apparatus for the manufacture of glass films and sheets, the com-
bination of a vessel adapted to contain molten metal, a plunger movable upward
through the same, but protected against contact with the molten metal, and a
detachable cap or head applied to said plunger, substantially as shown and
described.
14. In combination with a receptacle adapted to contain molten metal, a plunger
movable upward through the same, a cap or head applied to said plunger and over-
hanging the sides thereof, and a bait carried by said cap, and having a depending
flange or skirt to enter the molten metal.
15. In combination with a vessel adapted to contain molten metal, a bait formed
of glass and provided with a depending Hange, and means substantially as described
for lowering the bait until its Hange enters the molten metal, and subsequently
elevating the same.
Dated this 93ml day of November 1891
WM. P. THOMPSON & Co.,
Agents for the Applicant.