US1684440A - Sheet-glass-edge-forming means - Google Patents

Description

Sept. 18, 1928. 1,684,440

F. FRAsER SHEET GLASS EDGE FORMING MEANS Original Filed June 5, 1925 INVENT UIQ Patented Sept. 18, 1928.

UNITED STATES PATENT OFFICE.

FRANK FRASER, OF TOLEDO, OHIO, ASSIGNOR TO THE LIBBEY-OWENS SEEET GLASS COMPANY, OF TOLEDO, OHIO, A CORPOBATION OF OHIO.

SHEET-GLASS-EDGE-FOBMIN G MEANS.

Application filed June 5, 1925, Serial No. 35,082. Benewed September 26, 1927.

The present invention relates to sheet glass apparatus, and has particular reference to sheet edge forming means.

An important object of the invention s to rovide sheet glass apparatus for producng Eat sheet glass, and includes means arranged at both edges of the sheet adapted to engage and form a suitable edge on the sheet capable of over-coming the natural tendency of the sheet to narrow.

Another object of the inventions to prcvide stationary edge means for grppug the edges of the sheet at their bases and movable means above the stationary means to further assist in maintaining the sheet to width.

Still another object of the invention s to provide at each edge of the sheet being drawn from a mass of molten glass a statonary block member having a slot therein through which the edge of the sheet is drawn and rotatable rolls above the slot for assistng the block means in creating an edge on the sheet, the said rolls being adapted to either retard or advanee the edge glass.

Other objects and advantages of the invention will become apparent during the course of the following description.

In the drawings wherein like numerals are employed to designate like parts throughout the same,

Fig. 1 is a fragmentary transverse vertcal section through a sheet glass apparatusllustrating my improved device in operation,

Fig. 2 is an end view thereof,

Fig. 3 is a top plan, and

Fig. 4 is a perspective view.

This device is particularly well-adapted for use in the Colburn type of machine as set forth in Patent No. 1248809, granted December 4, 1917, although it is not necessarily limited to the Colburn machine as it can be used in any type of machine wherein a flat sheet of glass is drawn from a source of molten glass. 4

The numeral 5 designates a so-called drawing pot containing a mass of molten glass 6, from which a sheet 7 is drawn from the sheet source 8. A bending member 9 may be provided to deflect the sheet from one plane to another.

In the Colburn machine a pair of rotatable knurled rolls are positioned at both edges of the sheet being drawn at the meniscus thereof to form a so-called knu'led edge on the sheet to hold the same to width. The natural tendency of a sheet of glass being drawn from a mass is to narrow at its base and draw to a thread. One of the great difficulties in the production of sheet glass is to prevent this natural tendency of the glass to narrow without spoiling the quality of sheet formed.

Although the knurled rolls used in the Colburn process are entirely satisfactory, they form what is known as a knurled edge on the sheet and a thickened portion which extends about six or severi inches from the edges toward the center, which edges must be removed when the sheet is being cut up into commercial sizes. The net width of sheet is therefore considerably less than the gross width.

It is an aim of the present invention to provide means capable of holding the sheet to width, at least as satisfactorily as the knurled rolls now used, and which will also hold the sheet to width without creating such a large useless portion.

The numeral 10 designates what may be called a slotted block. The slot is indicated as at 11. The block may be fornd from a refractory material such as clay, or as shown in the drawings may be forned from a prefe-ably non-Corrosive metal which may be internally cooled as through the conduits 12. Thus the blocks may be formed with an internal bore having connection with the conduits 12, whereby a cooling medium such as air or water may be continuously ci'cnlated through the said block. The block may assume any number of shapes, and as shown in F ig. 2 comprise a pair of foot portions 13 which are adapted to be partially submerged in the bath of molten glass from which the sheet is drawn. As shown in Fig. 4 the slot is eontinued up the sheet for a comparatively high distance by making the neck 14 comparativelv taller than the neck 15 in Fig. 2. The bloeks may be carried on the arms 16 which are supported in any suitable manner. The slotted members have a duel function in that they create a positive frictional resistdnce to the glass passing into the bordet' portions of the sheet and they also absorb sufficient heat from this glass to create a relatively viscous edge capahle of overcoming the natural tendency of the sheet to narrow. The

glass will drag along the bottom of the shoes 13 because of the natural tendency of molten glass to adhere to such bodies.

The slot 11 may be enlarged at its end as at 17 to form what is known as a headed edge 18.

In addition to the slotted block just described, I provide preferably smooth rotatable rolls 19. One roll is arranged on each side ot the edge ot' the sheet as is clearly indicated in Fig. 4 directly above the slot ll, thus t'orming a continuation thereof. The rolls are supported upon the rotatable shafts 90 which nay be internally cooled and are supported and driven through the mecha msm 21. A changeable speed drive is desirable so that the speed of rotation ot the rolls *an be controlled. The rolls 19 may either be rotated faster than the speed ot' draw if it is found that the blocks are offering too much resistance, or if the blocks have not sutticient resistance, the rolls may be rotated relatively slower than the speed of draw. Of course the rate of rotation of the rolls and the speed of draw can be identical if desired.

lVith the smooth rolls which may be provided with a groove 22 to accomnodate the beaded edge 18, the sheet will be held to width while at the same time the comparatively large knurled edge formed on the sheet heretofore will not be in evidence. The eombination of the frictional resistance ot' the block,

as well as the heat absorption and the rotatable rolls, a decidedly improved edge will be formed on the sheet. The edges thus formed can be trimmed oti' and used for shelving purposes, etc., while the remainder of the sheet can be handled as heretofore.

Claims:

1. In sheet glass apparatus, means for drawing a sheet from a mass of molten glass, stationary means arranged at the base of the sheet at its edges for retarding the movement ot the glass entering the sheet edges, and rotatablc means arranged above the said stationary means and closely adjacent thei-eto.

2. In sheet glass apparatus` means for drawing a sheet from a mass of molten glass, slotted stationary means arranged at the base of the sheet and at its edges tor retarding movement of the glass thereto, and rolls arranged above said slotted member and closely adjacent thereto.

Tn sheet glass apparatus, means for drawing a sheet from a mass of molten glass, stationary slotted means arranged at the base of the sheet forretarding movement ot'glass to the border portions thereof, and a pair of rolls above each of the slotted means.

4. In sheet glass apparatus, means for drawing a sheet from a mass of molten glass, stationary slotted means arranged at the base of the sheet at its border portions thereof, and

a pair of rotatable rolls above each slotted member adapted to engage the edge of the sheet after it emerges from the said slot.

5. In sheet glass apparatus, means for drawing a sheet from a mass of molten glass, a slotted block arranged at the base of the sheet and one at each edge thereof` a portion of each of the blocks being disposed below the end of the glass from which the sheet is drawn, and a pair of rotatable rolls arranged above the slot in each block.

6. In glass drawing apparatus employing a source of molten glass from which a sheet is to be drawn, means partially submerged in the source of glass for engagement with both sides of the edge portions of the sheet being drawn to create a dragging action for retarding movement ot' the sheet at its border portions, and rotatable means arranged above the said stationary means and closely adjacent thereto. i

7. In glass drawing apparatus, employing a source of molten glass from which a sheet of glass is to be drawn, means at the edges of the sheet for holding the same to width; comprising a body portion and a plurality ot' lip portions extending therefrom and terminating below the level of the molten glass from which the sheet is drawn, and rotatablemeans arranged above the stationary means and closely adjacent thereto.

8. In glass drawing apparatus employiug a source of molten glass from which a sheet is to be drawn, a block having spaced lip portions thereon forming a slot through which the sheet beingdrawn passes for retardingthe movement of the border portions thereof, and a pair of rolls arranged above the slotted block for engagement with the'sheet.

9. In glass drawing apparatus employing a source of molten glassf'om which a sheet is to be drawn, a block having spaced lip portions thereon forming a slot through which the sheet being drawn passes for retardingthe moveent of the border portions thereof. a pair of rolls arranged above the slotted block for engagement with the sheet, and means for controlling the temperature of said slotted block.

10. In glass drawing apparatus employing a source ot' molten glass from which a sheet is to be drawn, a block having spaced lip portions thereon foruing as lot through which the sheet beingdrawn passes tor retarding the movement of the border portions thereot, a pair of rollsarranged above the slotted block for engagement with the sheet, and means for controlling the temperature of the slotted block and rolls.

Signed at Toledo. in the eounty of Lucas. and State of Ohio, this 3rd day of June, 1925.

FRANK FRASER.

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