US1610004A

US1610004A - Drawing flat sheet glass

Info

Publication number: US1610004A
Application number: US665051A
Authority: US
Inventors: Lawrence A Grolemund
Original assignee: Libbey Owens Sheet Glass Co
Current assignee: Pilkington North America Inc
Priority date: 1923-09-27
Filing date: 1923-09-27
Publication date: 1926-12-07
Anticipated expiration: 1943-12-07

Description

Dec. 7 1926.

www@

L.. A. GROLEMUN DRAWING FLAT SHEET GLASQ Filed Sept. 27. 1923 ATTNEY Patented Dee S'Tellll 'LAWRENCE A. GRCLEMUN?, 0F CHARLESTON, VIRGINA, ASSlG-NOE T0 THE LIBBEY--OVENSVSHETAT GLASS QOMPANY, GE TCL-EDO, GEIQ, A QOBGRATION 0F i nnanfrne naar Application lfiled September T his invention relates to improvements in the art of drawingat' sheet glass, and more especially to 'animproved method of and apparatus for regulating' the temperature oi individual transverse portions o'l the drawn sheet atan' 'intermediate stage of the sheet formation. i r The invention is'rnore'particularly applied to controlling the temperature o t-the sheet while it is still inv a semi-plastic condition and is being deiiected from a vertical to a horizontal plane prior to the flattening proc-A ess. In the. Colburn processor' drawing fiat vsheet glass. -as set v forth for example in the patent to l. lV. Colburn. 1,248,809, granted iDec.A 4, 1917, a sheet of glass is drawn upwardly from a pool of moltenfglass., and while substantially 'seti in sheet form, but stilll somewhat plastcnis deectedabout a bending roller into the horizontal plane Where it is carried away through suitable drawing and iattening'mechanism intothe leer. lt isessential 'that the temperature of the glass sheet., and of the bending roller, be very accurately controlled, since if the sheet and roller arey too hot` the 'sheet will stiel; 'to the 'roller kand be injured thereby. whereas it the roller or sheet are too cold the bending` process cannot be carried out without breaking thesheet. The ro'lleriis .ordinarily somewhat cooled internally by passing@l a cooling fluid. usually air. therethrough. A water-cooler is positioned below the roller and adjacent the glass sheet. this cooler serving; to cool the surfaces ol the sheet and 'roller before they contact with one another, and also serving` to shield the lower surface of the roller vfrom'the heated air currents passing up from the molten mas-:sot glass from which the sheet is dra-wn. The sheet, while still sufficiently plastic to be bent about the roller, becomes so chilled during the .bendinar process that it is necessary to rcheat the sheet somewhat as it leaves thegroldler in order .that it may be drawn away therefrom in fiat form. ller this purpose a pipe burner. consisting oit `a longitudinal se barnersarrangea transrerselyot the sheet so positioned that the vflames play upon the sheetiiust before it leaves the surface of the bending roller. Due to various causes. such changeable air currents passing through the machine,

ries oli separate flames or GLASS.

27-1923. Serial No. $65.05l.

the internal structure ol1 the bending member and sheet., and the difficulty of accurately controlling' the heating and cooling mechanism,'cold or hot spots sometimes develop in the bending` member or sheet, or both, which adversely affect the quality and' evenness ofthe finished glass sheet.

The aim .et the present invention is to separately control the temperature ot thc: roller and glass sheet at `longritudinally of the roller and transversely of the sheet. so that such'hot or cold spots may be counteracted and eliminated.

One object of the invention is to yprovide a sectional auxiliary cooler for the bending member comprising a series of separately controllable cooling chambers.

Another object is to provide a heat insulatingir shield for substantially all of those portions ofthe roller not in Contact with the glass sheet.y

Another object is to provide a reheating burner for the sheet. which burner is comprised of a series of independently regulatable sections` whereby the application of heat to the sheet may be controlled along' with or sel'iarately from the application of cooling! means to the roller as above noted.

Other objects and advantagesof the'invention will become more apparent from the following detailed description oi one approved Yform of the apparatus use-d.

ln the accompanying drawings:

Fig. is a longitudinal vertical section vtl'irougrh a portion of the sheet drawing` mechanism and the temperature regulating apparatus. The section is taken near the adjacent end of the bending roller as viewed inthis ligure.'-

Fie'. 2 is an end elevation ot' theco'olina and heating apparatus. the bending" roller being; shown in section in a plane nearer the observer than the plane of Fig. l.

'Fia'. 3 is an inner plan view of the insulating shield and auxiliary' cooler, parts beine broken away. The view is taken lool:- ing' from the position that' would be occupied b v the bending;` roller. f

l` s is an elevation also 'looking' from the position of the bonding; roller at the heating apparatus.

The gloss sheet l is drawn upwardly from the pool u molten 2 in receptacle 3, lbetween surface coolers e and the edge- After the sheet has been drawn to substan' tially itsliinal form, but -is still somewhat plastic, it is deflected-about the cooled bending roller 6 into a horizontal plane wherein it is drawn away over supporting rolls 7 and 8 into a suitable drawing and flattening mechanism not here shown. The bending roller 6 is cooled by passing a cooling Huid, preferably air, therethrough, as in previous practice. I

.Approximately P ofthe outer surface of rollerl 6 will always be in contact with the glass sheet 1. but the other 270o is ordinarily exposed to the air, and is subject to variable air currents of different temperatures, as well as dust and other materials that may be deposited on the roller from these air currents.

To protect the roller as far as possible from. these conditions, the shield 9, preferably of' arcuate contour with its center of arc lyingv substantially in the axis of the roller, is positioned beneath the roller with its edges terminating closely adjacent the vertical and horizontal runs of the glass sheet 1. The arcuate portion of this shield is preferably compose of two separated metal shells, the chamber formed therebetween being illed with asbestos or other'suitable insulating material. The inner wall 10 of the shield is spaced some little Adistance from the outer surface of roller 6, but` adjacent the ends of the shield, and the ends of the glass-carrying surface of roller 6, vertical partitions 11 eX- tend from the arcuate portion of the shield closely adjacent to the roller surface so as to form a substantially enclosed chamber about all of the glass-carrying portion of the roller not in contact at that time with the glass sheet. Preferably formed as 'a unit with this shield at the edge thereof adjacent the vertical run of the glass sheet 1, is a. Water-carrying chamber 12 extendinglongitudinally of the shield and transversely of sheet 1. A cooling iuid is fed to and through this chamber as in ordinary practice, and this shield serves the purpose of partially chilling the inner surface of the sheet before its contact with the bending -roller` as in the form of apparatus previously used.

An Iauxiliary cooler 13 is carried by shield 9 and positioned between the inner wall 10 of the shield. and the adjacent surface of roller 6. This auxiliary cooler is composed of a longitudinal `series of separate cham-' bers 14, here shown as' six in number, although any suitable number may be'used.

f Individual inlet pipes 15 and outlet pipes 16, extend to and from each separate chamber 14., to convey the cooling'water or other fluid to the chamber anddischarge it therefrom. Preferably these inlet and outlet p pipes may be grouped as shown in the drawings, and positioned Within the body of the shield 9, whereby they will be protected against temperature changes by theI surrounding asbestos packing. Each inlet pipe 15 .is provided with an individual control- 7U lingvalve 17, these valves preferably being' grouped at one end of the machine, as shown in Fig. 2. By separately manipulating these valves, the flowl of cooling luidihrough any y one or all 0f the chambers 14may be selec- 75 tively regulated. s

The reheating apparatus'ljcomprises, as has been the usual practicegat-I-ibular pipe or chamber provided with a longitudinal row of closely adjacentburner holes, where- 80 by a series 'of-separate iames-are projected in a line against the sheet surface so as to substantially form a continuous sheet or blanket of heating flame. In this new forni of burner, the pipe 18 is divided by aseries 85 of separate internal partitions 19 into a number of individual gas-holding chambers, here shown as six in number, although any suitable number may be used. A separate. inlet pipe 20 supplies gas to each chamber. 90 At one end of the machine, preferably the same end where valve 17 of the cooler is located, each of the gas-supplying pipes 20 is provided with a controlling valve 21. As

shown in Fig. 2, the supply pipes 20 may all 95 terminate in a single manifold 22 supplied from a main gas pipe 23. By miitably regulating the valves 21, the supply of gas to any of the separate chambers inpipe 18 may be limited or entirely cut oft' so as to control '100 the intensity or eliminate each individual group of flames at different transverse intervals across the sheet surface.

In normal operation, the cooler 12 will always be used, and ordinarily the entire seri-es of reheating burners will be in operation across the width of the sheet. The scries Vof auxiliary coolers 13 may or may not be normally necessary according tothe design of the apparatus. This will depend on the capacity of cooler 12 to sufficiently chill the surfaces of the sheet and bending member. If a hot spot develops in the roller A6 or in the sheet 1, or both, this may be counteracted by applying cooling Huid to that section or sections of cooler 13 nearest to this overheated portion of the roller. At the same time application of heat from burn--r er 18 may be restricted or entirely cut oif at the corresponding portions' of sheet 1. Conversely if. one portion of roller 6 or sheet 1 becomes too cool, th'e adjacent portions of the cooler 13 may be cut out by stopping the fiow of cooling fluid therethrough, and the intensity of thereheating burner 18 atA that 12 point may be increased. As shown in Fig. 2, thetwo end sections of cooler 13 are out of` service. the supply valves 17 being closed. ne of the inner sections of the reheating burner 18 is shut off, as indicated by the '150 lll) Leidens closed valve It Will be seen vthat with the combined applicatioii of these locally controllable heatinfy and cooling members, the temperature of di ierent transverse areas ot' the vsheet may be quite accurately regulated and variable disturbing factors which would ordinarily cause inequalities iii thn sheet may be large.` ly overcome. The protecting shield around those portions of the bending roller which Wouldordinai'ily be exposed to air currents also greatly. assists in maintaining even temperature conditions during the bending process.

Claims: l

l. ln apparatus for producing sheet glass, a cooler positioned transversely oi" the glass sheet, and comprising a. longitudinal series of separately regulatable sections.

2. In apparatus for producing sheet glass,l

a cooler positioned transversely of the glassv sheet, and comprising a longitudinally arranged series of separate clian'ibers, and means for independently and selectively' flowing a cooling fluid through each chamber.

3. In apparatus for producing sheet glass, a cooler positioned transversely of the glass Sheet, and comprising a longitudinally arranged series of separate chambers, individual inlet and outlet pipes leading to each chamber, and nie-ans accessible from outside the machine for controlling the flow ot cooling fluid to each chamber.

4. The combination with a sheet glass drawing apparatus, comprising a bending member about whiclitlie sheet is deflected from one plane to another, of means for controlling tlie temperature of the bending member and the glass sheet, comprising a cooler formed of separately regulatable sections positioned adjacent the bending men ber.

5. The combination with a sheet glass drawing apparatus -comprising a bending member about which the sheet is deflected from one plane to another, of means for controlling the temperature of the bending ii'ieniber and the glass sheet, comprising a cooler formed of a series ot' separate chambers arranged longitudinally of and adjacent the bending member, and connections for independently flowing a cooling fluid through ear-h ot the chambers.

G. The combination with a sheet glass drawing apparatus, comprising abending member about Wiiicli the sheet is deflected from one plane to another, of means for controlling the temperature of the bending member and the glass sheet, comprising a. cooler formed of a series of sepaiiiif.-y chambers arranged longitudinally of and adjacent the bending member, individual inlet-and outlet iipes tor a cooling fluid leading to each ciamber, and means accessible from 2l at the upper right ot' Fig. 2.'

outside the machine 'for controlling the tiow vwith heat insulating material, enclosing substantially7 that portion ot the bending member not in contact with the glass sheet. 89 The combination with sheet glass comprising a bending;

'drawing apparatus, comprising a bending member about which the slieetis kdetlected troni one plane to another, with heat insulating Stantially that portion oi tliel'icnding meinber not iii contact with the glass sheet, a sectional cooler positioned l'ietu'eeii the shield and member, and means for separately eon-` trolling the several cooler sections.

9. The combination with a sheet glass drawing` apparatus, comprising' a bendingr member about which the sheet is defiec-te from one plane toanotlier, of a shield lined with heat insulating material, enclosing substantially that portion ot the bending 'meinber not in contact with the glass sheet, a cooler comprising a series of se arate chambers positioned between the shie d and member, aiidseparate connections for feeding a cooling huid to each chamber, 'the connections being protected by the insulating material of the shield. I

l0. ln apparatus for producing sheet glass, a heater positioned adjacent and transversely of the glass sheet, comprising a longitudinal series of burners, and means for separately feeding and controlling different groups of these burners.

1l. In apparatus for producing sheet glass, a heater positioned adjacent and transversely 'of the glass sheet, comprising a tubular member having a longitudinali row ot. burner outlets, the tubular member being interiorly divided 'inte a series ot separate chambers, and means for yindependently feeding gas to eaclr chamber.

12x-The combination with a sheet lass drawing apparatus, comprising a ben ing member about which the sheet isdellected from one plane to another, of a heater for controlling the temperature of the sheet as it leaves the bending member, the heater being formed of a series of separately controlled sections.

13. The combination with a sheet glass drawing apparatus. comprising a bending member about which the vsheet isdet'iected from one plane to another, of. a heater for controlling-the tcn'iperature of lthe sheet as .it leaves the bending member, the beater comprising a longitudinal series of burners arranged transversely of the glass sheet, and means for independently feeding and controlling' separate groups of these burnersa let. The combination with a sheet glass l ot' a shield lined*A material, enclosing s ub-` 4drawing apparatus, comprising a bending member about which the sheet is deflected from one plane to another, of means for controlling the temperature of the bending member and the glass sheet, comprising a cooling member and a heating member arranged transversely of and adjacent) the bending member and sheet, both the cooler and the heater being formed of' a series 'of independently regulatable sections.

15. The combination with a sheet glass drawing `apparatus. `comprising a bending"I member about which the sheet is deflected from one plane to another, of means for controlling the temperature of the bending' member and the glass sheet, comprising a cooling member and a heating member arranged transversely .0i and adjacent the bending member and sheet, both thecooler and the heater beingI formed of a series ofy separate chambers, and meansfor independ-'- perature of a glass sheet, and a member" about which the sheet may be deflected from one plane to another, -which consists. in`

creating heat absorbing zones in proximity vto the deflecting member, and then regulating the temperature of each zone in a Inanner to make uniform thel temperature of said deiecting member. Signed at Charleston, in the county of Kanawha and State of West Virginia, this 17th day of September, 1923. f LAWRENCE A. GROLEMUND.