Improvements in the Manufacture of Glass.
Year: 1891

page_text: Date of Application. 11th Mar., 1891
Complete Specification Left, 11th Dec., 1891-Accepted, 16th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Glass.
I, THOMAS COOPER JOHN THOMAS, of 5 Carlton Road, Finsbury Park, in the
County of Middlesex, Engineer, do hereby declare the nature of this invention to
be as follows:-
In the Specification of Letters Patent granted to me No. 12076 of 1886, I
have described improvements in the manufacture of glass consisting in subjecting
the frit or material of which glass is to be made to the action of oxygen which is
caused to pass through the frit or material when the same is in a fused state, the
object being to eliminate impurities and produce glass of improved quality in a
quicker and more economical manner than usual.
Now my present invention has for object to recover the oxygen escaping from
the glass pot or other receptacle in which the frit or other material (hereinafter
referred to as frit) is treated, so that the oxygen can be re-used and the cost of
the process correspondingly reduced.
For this purpose I use a glass pot or other receptacle for example a tank
furnace (hereinafter included in the expression, a glass pot) that is suitably closed
during the treatment of the frit by oxygen, and in conjunction with this glass pot
I use a gas holder into which the oxygen escaping from the surface of the molten
glass can pass and from which it can be subsequently withdrawn for re-use.
The oxygen can be supplied in a compressed state from reservoirs such as the
steel tubes or cylinders in which it is usually sold, but I prefer to supply it by a
gas compressor that has its inlet in communication with the gas holder above
referred to, or other reservoir, and its outlet in communication with the interior of
the glass pot. When a glass pot proper is used, I prefer to place it with its axis
in an inclined position its outer end being provided with a cover having an opening
for the passage of an oxygen supply pipe, an outlet for the escape of oxygen to
the gas holder or gas compressor, and a sight hole normally closed by a plug.
When the oxygen is supplied to the frit by a tube of refractory material inserted
into the glass pot from above, which is the plan I prefer, I use a tube that is
closed and pointed at one end to facilitate its introduction into the frit, and is
formed for a portion of its length with numerous lateral holes for the escape of
oxygen.
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Glass.
I, THOMAS COOPER JOHN THOMAS, of 5 Carlton Road, Finsbury Park, in the
County of Middlesex, 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:-
In the Specification of Letters Patent granted to me No. 12076 of 1886, I
have described improvements in the manufacture of glass consisting in subjecting
the frit or material of which glass is to be made to the action of oxygen which is
5 caused to pass through the frit or material when the same is in a fused state, the
D
1

page_text: object being to eliminate impurities and produce glass of improved quality in a
quicker and more economical manner than usual.
Now my present invention has for object to recover the oxygen escaping from
the glass pot or other receptacle in which the frit or other material (hereinafter
referred to as frit) is treated, so that the oxygen can be re-used and the cost of
the process correspondingly reduced.
For this purpose I use a glass pot or receptacle that is suitably closed during
the treatment of the frit by oxygen, and in conjunction with this glass pot I use
a gas holder into which the oxygen escaping from the surface of the molten glass
can pass and from which it can be subsequently withdrawn for re-use.
The oxygen can be supplied in a compressed state from reservoirs such as the
steel tubes or cylinders in which it is usually sold, but I prefer to supply it by a
gas compressor that has its inlet in communication with the gas holder above
referred to, or other reservoir, and its outlet in communication with the interior of
the glass pot.
When a glass pot proper is used, I prefer to place it with its axis
in an inclined position its outer end being provided with a cover having an opening
for the passage of an oxygen supply pipe, an outlet for the escape of oxygen to
the gas holder or gas compressor, and a sight hole normally closed by a plug.
When the oxygen is supplied to the frit by a tube of refractory material inserted
into the glass pot from above, which is the plan I prefer, I use a tube that is
closed and pointed at one end to facilitate its introduction into the frit, and is
formed, for a portion of its length, with numerous lateral holes for the escape of
oxygen.
In the accompanying drawings,
Fig. is a diagrammatic view shewing apparatus suitable for carrying my
invention into practice.
Fig. 2 is a longitudinal central section of a gas supply tube.
1 is the glass pot in which the frit is melted. It may be of the ordinary or
other suitable form and is heated in the ordinary manner in a glass furnace 2 of
any approved construction as for example a Siemens glass furnace. The glass
pot which may advantageously be arranged and supported with its axis in an
inclined plane as shewn, has connected to its outer end, with a gas tight joint, a
cover 2 formed with an opening at 3 for the passage of the -perforated oxygen
supply pipe 4 which may be of platinum; with a sight hole at 5 normally closed
by a plug and with an outlet pipe 6 that is in communication when the cock 6ª
is open, with a gas holder
of ordinary construction, (that is) consisting of a
vertical open bottomed counterbalanced cylinder inserted in a tank of water as
well understood. 8 is a gas pump or compressor of any suitable construction
having its suction opening in communication with the gas holder 7 and its delivery
opening, when the cock 8 is open, in communication with the supply pipe 4 and
acting to force oxygen from the gas holder into and through the molten frit in the
glass pot. Or in lieu of a gas pump or compressor, a gas reservoir or tube 8
such as shewn in dotted lines, may be used for supplying the oxygen at a suitable
pressure to pass through the molten frit, say at a pressure of from 14 to 25 pounds
per square inch.
The supply pipe 4 when of platinum may be about inch in diameter and is
formed with numerous small holes of say inch diameter for the escape of oxygen
into the bath of molten frit. I may use a perforated pipe of refractory material
such as fire clay instead of the platinum tube.
The glass pot when charged with frit is heated in the usual manner, and when
the frit begins to soften or melt, the cover 2* is fixed in place, the oxygen supply
pipe 4 is introduced into the mixture, and a supply of oxygen turned on, the
oxygen passing through the frit and assisting its fusion; or the cover 2 and
pipe 4 may be inserted in place, and the oxygen turned on before the frit begins to
soften. The oxygen after escaping from the pipe rises upward through the bath
of molten glass and agitates the same, burning out carbonaceous matters that may
be present therein, and removing impurities which rise as a scum to the surface,

page_text: and are skimmed off when the process is complete, which may be ascertained by
sampling. The oxygen escaping from the surface of the molten glass passes
through the outlet pipe 6 and thence to the gas holder 7 for subsequent use.
When the impurities are eliminated the cover 2* and supply pipe are removed
and the supply of oxygen cut off before removing the glass from the pot; or
the viscid glass may be removed in the ordinary manner while the pipe is in
place.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:―
In the manufacture of glass by subjecting frit or material of which glass is to
be made to the action of oxygen, collecting and re-using substantially as herein-
above described with reference to the drawings the oxygen that escapes from
the surface of the molten glass in the pot or vessel wherein the glass is treated
as set forth.
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.