US463642A - Method of and apparatus for the manufacture of plate-glass - Google Patents

Description

2 SheetsSheet- 1.

(No Model.)

R.-S. PHASE. METHOD OF AND APPARATUS FOR THE MANUFACTURE OF PLATE'GLASS Patented Nov. 24, 1891.

(N0 Modem 2 Sheets-Sheet 2. R. S. PHASE. METHOD OF AND APPARATUS FOR THE MANUFACTURE OF PLATE GLASS.

,642. Patente d Nov. 24, 1891.

Winesses;

UNITED TATES FFICE.

ATENT ROGER S. PEASE, OF ROSE, ASSIGNOR OF ONE-HALF TO 'COURTLANDT RAB- COCK AND AMBROSE B. EVERTS, OF MINNEAPOLIS, MINNESOTA.

METHOD OF AND APPARATUS FOR THE MANUFACTURE OF PLATE-GLASS.

SPECIFICATION forming part of Letters Patent No. 463,642, dated November 24, 1891.

Application filed February 11, 1891. Serial No. 381,011- (No model.)

To aZZ whom it may concern:

Be it known that I, ROGER S. PEASE, a citizen of the United States, residing at Rose, in the county of Ramsey and State of Minnesota, having my place of business and postoflice address at Minneapolis, Minnesota, have invented certain new and useful Improvements inMethods of and Apparatus for the Manufacture of Plate-Glass, of which the fol- 1o lowing is a specification.

My invention relates to the manufacture of plate-glass and it consists, primarily, in pouring the metal directly upon the molding table or bed from pots within the furnace or melt- 5 ing-oven, so as to avoid the necessity of either first drawing off the metal from a tank or of removing the pots from the oven and subjecting them to'changes of temperature.

In the annexed drawings, Figure l is a lon- 2o gitudinal sectional view of a pot-furnace arranged for-carrying out my invention, the molding-bed being represented as standing beneath the pot-chamber ready to receive the molten metal; Fig. 2, a transverse sectional view showing one of the pots in the act of being emptied; Fig. 8, a perspective view showing the end of the furnace or moldingtable and the car or table which conveys the glass from the molding-table to the annealing-oven; Fig. 4, a View illustrating the preferred form of the pot; Fig. 5, a sectional view showing the preferred construction and arrangement of closure for the opening through which metal is poured and indicating the relation of the pot thereto.

Many attempts have been made hitherto to simplify and cheapen the manufacture of plate-glass, and particularly to render the melting process continuous. 'WVi'th this object in view some have proposed the use of tanks adapted to contain a large quantity of molten metal and to maintain the same in proper working condition, the design being to draw from the tank the quantity required for the formation of one sheet after another and tosupply materials to the tank or to the melting-chamber in proportion to the withdrawal of molten metal therefrom. In some cases it has been proposed to tap the tank through its bottom or in line with its bottom through one side; but experience has proven that this plan is open to a very serious objection, which is that wherever molten glass flows through an opening in the bottom or wall of a tank the opening becomes rapidly enlarged, the fire-clay fusing with or being eaten by the molten glass, so that it is difficult to properly close it or to regulate the flow of'glass through it. Others, recognizing the above difficulty, have proposed to tip the entire tank or to lower one side thereof, so that the molten metal may flow over its edge; but provision has usually been made for delivering the metal into portable pots, whence it was to be poured upon the molding-table. I propose to avoid the difficulties attending these several plansenlargement of the tap or opening on the one hand or the expensive construction involved in a tipping tank on the other-by making use of pots and so arranging them that their contents may be discharged directly onto the molding or casting table without removing the pots from the furnace, and I have found by practical tests that this plan is admirably adapted to the manufacture of plate-glass and effectually overcomes the difficulties encountered by prior plans.

Referring now to the drawings, A indicates a melting oven or chamber containing a series of pots B, which may be of any suitable capacity, and which are advisably arranged in two rows or groups, one row at either side of the furnace or oven close to the outer walls thereof. Thus arranged the pots may be 5 readily charged and tipped to discharge their contents through openings 0, formed in the side Walls of the furnace or oven, and normally closed by suitable caps or stoppers D, such as are used to close the working-holes 9 of pot-furnaces.

E indicates an opening through the floor or bottom of the oven or chamber B, which opening extends parallel with the side or end walls of the oven and is located midway between said walls, the pots B being arranged to face said openings, so that when tipped their contents shall fiow through the same without coming in contact with the walls or edges thereof.

The opening E may be closed by bricks or blocks F of fire-clay laid over the same and IOC manipulated by means of a suitable rod in the hands of the workman, or, as is preferred, the opening may be of the form indicated in Fig. 5, and closing doors or gates G employed to close the opening E.

The bottom or floor of the chamber A is made of fire-clay or fire-brick and inclines downward toward the opening E, as shown in Figs. 2 and 5, this for the double purpose of causing any drip or-waste that may occur to flow to the opening E and also to afford free space for the tipping of the pets to any extent desired.

As indicated in Figs. 1, 2, and 5, the floor of the chamber or oven A is provided with a backing or support a, of iron orother suitable metal, and in the preferred form represented in Fig. 5 the floordrops or inclines downward toward the opening E both inside and outside. Hinged to the backing a at suitable points are the doors or gates G, which are counterweighted, so as to close automatically and to remain closed, except when forcibly drawn open by the attendants, the meeting line of the two doors being so formed that the gates may swing down one after another without looking or binding. A convenient form is represented in Fig. 5, Where the meet ing line is oblique to a vertical plane; but obviously the meeting line may be a curved instead of a straight line or plane. The counter-weights G may be caused to act with any desired force, so that, if desired, the gates shall remain closed even though the contents of one or more of the pots be discharged thereon through the breaking of a pot or otherwise.

To open the gates G, I provide, preferably, chainsor cables H, which pass about pulleys b, and thence to the front of the furnace or other convenient point, where they may be provided with hand-holds or attached to levers by which to pull upon them and draw upward the counter-weights G, whereby the gates may be opened.

As indicated in Fig. 5, the gates G are formed with metal backings and faced with fire-clay, so as to withstand the high heat within the oven or chamber A.

A single gate may be substituted for the double gates shown; but I prefer the double gates, because of the greater compactness or the smalleramount of vertical space required, it being desirable that the molding or casting table I be brought as near to the bottom of the chamber A as practicable.

In practice it will be found desirable to employ as many gates (double or single) as there are pairs of pets, so that only that portion of the opening E which is directly 'in front of the pot or pets to be poured need be opened at any one time. \Vithout such provision there would be a serious waste of heat and an undue cooling of the pots and the metal.

therein.

In order to bring the molding or casting table I as near to the bottom of the chamber as is practicable, I mount the floor of said chamber upon iron beams or girders, which are in turn carried upon columns or piers, so as to leave a free space below the chamber for the molding or casting table and permit access to said space when required.

The molding or casting table I is essentially the same as heretofore used, and is mounted upon trucks or wheels and arranged to run into and out of the space beneath the chamber upon suitable rails, as indicated in Figs. 1, 2, and 3.

.I indicates the roller by which the glass is rolled out and caused to assume the proper thickness upon the bed ortable, which latter is furnished, as usual, with side guards or ways upon which the ends of the roller travel and by which the thickness of the sheet is determined. At the forward or outer end of the table are raised ribs or ways 0, which serve to elevate the roller when its work is completed and afford space between it and the table for the passage of the sheet from the table to the annealing-oven or to a transfercar K, by which the sheet is carried to the anhealing-oven.

Mounted on suitable standards or bearings at the forward or outer end of the molding or casting table I is a transverse shaft L, provided with cranks or winches by which to rotate it and with sprocket wheels (I, as best shown'in Figs. land 3. At the rear end of the table is asimilar shaft M, provided with wheels 6, which may be either grooved pulleys or sprocket-wheels. Passing about the pulleys (Z 6 at each side of the table are chains N, which have attached to them the boxes or bearings f of the roller J, so that as the shaft L is turned in one or the other direction the roller J will be caused to traverse the table I in one or the other direction, as desired.

0 indicates a guard resting upon the bed or table I and having a perforated lug or car, through which passes the journal of the roller J, so that the guard is carried with the roller in its movements forward and backward, there being a similar guard at each end of the roller to prevent the molten glass from flowing over the sides of the table as the roller advances.

The arrangement of the roller-chains and shafts above set forth is peculiarly advantageous in connection with my method of operation for the reason that it enables me to cause the backward as well as the forward movement of the roller Without drawing the molding-table out from beneath the chamber or oven A, whereas prior constructions would necessitate the drawing out of the molding or casting table or the use of some other means in addition to the ordinary chains by which the roller is drawn forward to recede the same.

hile I have described the chamber as having a central opening with a series of pots on either side thereof, I wish it distinctly uneeaeaa derstood that I do not restrict myself to this arrangement, as I may obviously use a single row of pots or I may arrange the pots in other waysfor instance, in a semicircular group,

in a single straight line along one side of the opening, or otherwise-though I prefer the arrangement illustrated for the reason that it affords convenient access to each of the pots and enables me to charge and to tip the same with ease and facility. So, too, I have represented the passages for the inlet of air and gas from a regenerator such as is employed in the well-known Siemens type of furnace;but I do not restrict myself to this or any other specific form of heating apparatus.

Under ordinary circumstances I prefer the type of heater indicated, because of the intense heat obtainable therefrom, the cleanliness and freedom from smoke and sulphur, and the economy of fuel.

The pots which I propose to employ, although ordinary pots may be used, are of the form shown in Figs. 2, 4, and '5that is to say, the front side is rounded or cut away to such an extent that a Very slight pressure forward will cause the pot to tip and discharge its contents and so, too, that the movements of the pot may be easily controlled throughout, the rounded rocking or bearin g faces permitting the easy control and tipping of the pots to any extent desired. A sufficiently flat surface or bottom is left for the pot to stand upon normally Without the aid of props of any kind, as indicated in Figs. 2 and 5. This peculiar formation of the pots is important to the practical carrying out of my improved method, because of the necessity of tipping the pots within the heating or melting chamber, and, further, because it is essential that the contents be discharged in a mass and not allowed to drip or trickle from the pot, because such slow discharge causes the molten metal to fold upon itself and to inclose bodies of air, which form bubbles in the sheet rolled therefrom.

No claim is made in this application for the pot per se, as that is specifically claimed in another application filed in my name on the 19th day of September, 1891, Serial No. 406,177. It is here shown and described merely to afford a full and clear understanding of the best mode and means of carrying out the process herein claimed.

By retaining the pots within the chamber or oven A at all times and pouring the metal therefrom while within said chamber I avoid the changes of temperature both in the pot and in the molten metal which are incident to the delivery of the molten metal from a tank into an exposed pot or ladle, or to the removal of a pot from an oven or furnace to the atmosphere, and, I consequently greatly prolong the life of the pots, at the same time insuring a more uniform quality of glass and rendering far more easy and certain the casting operation.

The pots may contain differentcolored metal, so as to produce sheets of different colors or combinations of colors.

Thepots may be covered or open, as preferred.

By some glass-workers or under some circnmstances it is deemed advantageous to roll the sheet in both directions one or more times. Hence I do not wish to be understood as restricting myself to the arrangement of the guards 0 above described, but propose to adopt in some cases the common plan of connecting the guards by a cross-bar or plate and mounting them loosely upon the table in advance of the roller J.

It is and long has been common to construct a pot-chamber with an inclined bottom leading to a small outlet for the escape of molten glass spilled from a pot or escaping from a broken pot, and I make no claim to this idea.

In order to secure the practical benefits of my plan, it is necessary that the pots be arranged in such relation to the opening and that the opening be of such size as to permit the molten glass to be poured. directly upon the molding bed or tablethat is, Without coming into contact with the walls of the opening.

I am aware that it has been proposed to tap or siphon molten metal from a melting-chamber directly to a mold, and subsequently to carry said mold beneath a press and subject its. contents to pressure, such plan being set forth in British Patent No. 14,573 of 1885. I make no claim thereto.

It is particularly to be noted that under my arrangement of apparatus and method of working the vessel containing the molten metal remains always within the melting chamber or oven, and is consequently heated evenly in every part. tipped to pour the metal said metal flows over a mouth or edge and through a space heated to the same temperature as the body of the pot and the metal itself, touching nothing whatever that might chill it until delivered upon the molding or casting table. Then tapped or siphoned from a tank, the metal is chilled by contact with the external, exposed, and comparatively cool lip in front of the outlet and falls to the mold through the outer airthat is, through air outside of the furnace or heating-chamber.

So far as I am aware, no one has ever before proposed to manufacture glass by pour ing the molten metal from a pot contained in the melting chamber or oven and without removing the pot therefrom. By this plan I am enabled to vastly prolong the life of the pots, avoid chilling or cooling of the metal, and insure the formation of perfect plates at Hence when the pot is IIO greatly-reduced cost as compared with prior stand the heat required, and the materials of which glass pots are made preclude the use of trunnions and like supports.

Having thus described my invention, I claim 1. The herein-described method of molding or casting glass plates or sheets, which consists in first reducing the charge of metal to a molten state in a pot or crucible within a melting chamber or oven; second, tipping the pot or crucible and pouring the molten metal therefrom directly to or upon the moldingbed or table without removing the pot or crucible from the chamber or exposing it to the outer air, and, third, rolling or spreading the mass into a sheet of proper thickness.

2. The herein-described method of producing glass plates or sheets, which consists of the following steps: first, reducing the batch or charge to a molten state in a pot or crucible within a melting chamber or oven; second, tipping the pot or crucible and pouring the molten metal directly therefrom to or upon the molding bed or table without removing the pot from the chamber; third, rolling or spreading the mass into a sheet, and, fourth, annealing the sheet.

3. In an apparatus for the manufacture of glass plates or sheets, the combination of a heating oven or chamber provided with an opening through which molten metal can be discharged without coming into contact with the floor of the chamber or the walls of the opening, a pot or pots within said chamber, adapted to contain molten metal, and a molding or casting bed located in such relation to the opening in the furnace and to the pot or pots therein as to directly receive the molten contents'of the latter when poured, substantially as set forth.

4. In combination with chamber A, provided with opening E, a pot or pots B, arranged in such relation to the opening that the contents can be poured directly through said opening, and a casting or molding table I, located below the opening E, substantially as shown and described.

5. In combination with chamber or oven A, provided with an opening E in its floor or bottom, gates or doors G, adapted to close said opening, and a pot or pots located within said chamber and adapted to deliver molten metal directly through said opening, substantially as described.

6. In combination with chamberor oven A, provided with opening E in its floor or bottom, gates G, applied to said opening, counter-weights G, adapted to hold the gates closed, anda pot or pots located within chamber A and in such relation to the opening as to deliver molten metal directly through the opening E when tipped.

7. In combination with chamber or oven A, provided with opening E, counterweighted gates G, and chains or hands H for opening the gates, substantially as described.

8. In combination with chamber or oven A, provided with opening E, a pot or pots having a front face rounded or cut away substantially as shown, whereby the pot is adapted to be rocked or tipped forward and held in any desired position with the exercise of slight power.

9. In combination with a molding or casting table I, roller J, chains or bands N, shaft L, and wheels or pulleys cl 6, about which said bands pass, all constructed and arranged substantially-as set forth, whereby the roller is adapted to be moved forward and backward over the table without drawing said table from beneath the furnace or oven in connection with which it is used.

In witness whereof I hereunto set my hand in the presence of two witnesses.

ROGER S. PEASE.

Witnesses:

WALTER DODGE, \VILLIAM W. Donen.

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