US1735353A - Method of and apparatus for annealing glassware - Google Patents

Description

Nov. 12, 1929. v, MULHOLLAND 1,735,353

METHOD OF AND APPARATUS FOR ANNEALING GLASSWARE Filed Sept. 10, 1923 3 Sheets-Sheet 1 Nov. 12, 1929. v. MULHOLLAND 1,735,353

METHOD 6? AND APPARATUS FOR ANNEALING GLASSWARE Filed Sept. 10, 1923 3 Sheets-Sheet 2 'v. MULHOLLAND 5,353

Nov. 12, 1929.

METHOD OF AND APPARATUS FOR ANNEALING GLASSWARE Filed Sept. 10, 1923 3 Sheets-Sheet 3 Patented Nov. 12,- 1929 UNITED STATES PATENT OFFICE VEB'GIL MULHOLLA 'ND, OF WEST HARTFORD, CONNECTICUT, ASSIGNOR TO HARTFORD- EHPIRE COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF DELAWARE METHOD OF AND APPARATUS FOR ANNEALING GLASSWABE Application filed September 10, 1923. Serial No. 861,827.

This invention relates to a method of and apparatus for annealing glassware, and particularly for annealing it as it passes rapidly in continuous procession from the ware shaping or forming machines in quantity production.

Glassware, afterfbeing shaped in a mold. is ordinarily removed therefrom while still very hot and annealedby gradually cooling it to atmospheric temperature. If merely set out in the open air it will cool too rapidly andunevenly. Its outer surface will cool and contract morerapidly than its interior portions, thus altering the relative dimensions and locations-of different portions of the piece and creating stresses therein, which tend to disrupt it. To avoid'or minimize these stresses is the object of annealing. If

not sufliciently-or properly annealed, so that undue-internal stresses still exist therein, the articlebreaks easily when used or handled, and may even-fly into small pieces sponta 'neously.

When removed from the mold, the different portions of the article are usually not at the same temperature. Those portions which have been in direct contact with the shaping mold or other metallic parts, and-especially its thinner portions, are at a lower temperature than other portions of the article. In general, 'the interior portions of the walls of the article are considerably hotter and more plastic than are the surface portions, so that frequently a newly molded article is held in shape onlyby its less plastic surfaces. In some instances. the articles, especially those having walls of uniform thickness, are sufficiently uniform in temperature and plas ticity to be initially free from-undue internal stresses. In other instances, due to lack of uniformity in wall thickness, temperature and plasticity, the article will be full of internal stresses directly after leaving the mold.

In some of the latter instances some arti cles do, and others do not, contain an amount of heat which if uniformly distributed of glassware, sometimes from different ma-- is known as a chines, are at various times delivered to the same leer. An adequate leer for general commercial use should, therefore, be adapted to tion sufficiently plastic to release any thenexisting stresses. With existing apparatus, however, such equalization is more or less imperfect and incomplete, so that different articles, or difierent portions of the same article, are at unequal temperatures and unequal conditions of stress when the next step, whichis that of cooling the articles, begins. This inequality of condition at the beginning of the cooling stage is likely to continue and increase throughout that stage, so that initial stresses remain, and additional stresses are produced on account of lack of provisions for distributing the heat and for equalizing the temperature by the transference of heat between different articles and between clifferent portions of the same article. This cooling is usually done slowly because of the difliculty, with existing commercial methods and apparatus, of cooling rapidly and at the same time uniformly enough to avoid unequal contraction of the partially plastic. glass and the consequent setting up of new internal stresses.

In annealing glassware commercially, it is customary to pass the ware, disposed in. several longitudinal rows side by side, on a metallic conveyor through'a masonry passage or tunnel heated with a fire box to a low red heat at the entrance'end, and having a gradually decreasing temperature toward the dis charge end where it is at the prevailing atmospheric temperature. Such an apparatus tunnel leer.

This customary form of tunnel leer for annealing glassware has various disadvantages among which are the following: It requires a considerable quantity of fuel. Thetime required for annealing the ware is from 2 to 5 hours, depending on the kind of ware, the bulk of such ware requiring at least four hours to anneal. This long period between the shaping of the ware and its inspection, permits defective ware to remain undetected for this period, during which the shaping machine frequently continues to produce ware having such undetected defects, which results in a considerable loss of ware.

The size andweight of such a leer large enough to hold the large amount of ware produced during such a long annealing period is considerable and its first cost is high. It is made of heavy masonry and requires substantial foundations. It must, therefore, be located with regard to these conditions, must remain where built and cannot easily be lengthened or shortened. On account of the bulk of masonry and metal work which it contains, and their capacity for absorbing heat and wasting it by conduction and radiation to the outside, considerable fuel is required to bring it up to and maintain it at proper operating temperature. Moreover, the annealing done by it is frequently more or less uncertain and incomplete due not only to inadequate control of the initial heating and the rate of subsequent cooling of the ware,

but also to considerable differences in temperature between difierent points in the same transverse section or zone of the tunnel. This causes or permits too wide a difference in temperature between diiferent portions of the same article and between difierent articles of the same transverse row, as the articles advance through the leer. For instance, .the

bottom end ofan article being at the bottom of the tunnel, and in contact with the colder metallic conveyor, is frequently much colder than the upper end of the same article, as it advances through the leer. Similarly the articles at either end of a transverse row of articles advancing through the leer may differ in temperature from other articles in the same row. This results in a difierent rate of cooling for different articles in the same row, and also tends to preclude proper annealing of many of the articles even if each article itself should be at a uniform temperature throughout. These conditions tend to produce, even with a slow rate of cooling, a faulty annealing of the ware.

If all portions of a, glass article which is being annealed are brought to a uniform an nealing temperature, and the subsequent cooling be kept uniform as to all its portions, it can be cooled much more rapidly than, in the present annealing leers, and yet be perfectly annealed Without undue internal stresses For example, if the article is enclosed in a metallic container and kept out of contact with the container walls, both. article and container being at a suificiently high and even temperature throughout, and the container isthen cooled evenly throughout all portions, the article can be cooled in from 25 to 30 minutes to a temperature at which it 'may be'safely v handled and be properly annealed. This is because all portions of the article, beginning at a sufficiently high and equal temperature, radiate their heat uniformly and equalize it, so that at no time during the cooling are there substantial temperature diiferences betweenthe difierent portions of the article, thus avoiding the setting up of stresses therein by unequal contraction. The factors contributing to this result include the rapid and uniform distribution of heat throughout the article by radiation and reflection thereof between the container and the article; the exclusion of air currents which would otherwise cool some portions of the article more rapidly than other portions; and the cooling of the container at a rate su'diciently uniform and rapid to reduce its temperature just far enough below that of the article to permit the desired rate of cooling of the article, by transference of its heat to the container, such a temperature differential or gradient, varied as desired, being maintained until the article is suiiiciently cooled.

There is, however, a certain critical range of temperature between that at which the article is partially plastic and that at which it is completely set. If cooled too rapidly while passing through this critical range, internal stresses will be set up in the article, and it will not be properly annealed. There is, for any kind of glass and type of article, a permissible maximum rate of cooling, which may improving the result. After the article has been cooled throughout its critical range of temperature at a sutliciently slow rate, it may then be cooled very rapidly to a temperature at which it may be safely handled.

Under the ideal conditions created by enclosing the article as above described, this maximum rate of cooling may be attained, whereas under ordinary manufacturing conditions obtaining with previous forms of tunnel leers, such ideal conditions do not exist and the uniform and maximum rate of cooling cannot be closely approximated.

Most glass articles made in quantity have sufiicient heat yet remaining in them when removed from the shaping mold so that their annealing may begin at the proper temperature without supplying additional heat, provided that the heat already in each article is properly conserved and redistributed. If, for instance, the article is transferred from the mold while still hot, directly into a proper scribed be satisfactorily and quickly annealed in separate enclosing containers, the problem of so annealing the ware coming rapidly in a continuous procession in quantity production from the ware forming machine or, machines,

' presents various'difiiculties. To provide and handle enough of the above described con- 'tainers would be difficult and expensive, and

in view of the present invention, unnecessary.

It is an object of my invention to combine and correlate the above described features, as far as possible, to save fuel and reduce the time of annealing, as well as to overcome or minimize the various disadvantages of the present tunnel leer. More specifically the object is to create a proper, environment through which the glassware may be moved continuously on a conveyor and be subjected as nearly as possible to the ideal cooling conditions and cycle obtainable with the above described individual containers, so as to produce better annealing thanhas been customary in commercial manufacture of glassware, and to reduce the time and cost of the operation.

Another specific object is to provide a leer and method of operation capable of annealing glassware as far as possible without fuel; that 1s, without supplying other heat than that of the articles themselves. Other objects ofvmy invention will be apparent from the following description.

The ware is passed through a leer tunnel whose walls are constructed so that the various portions of the tunnel may be quickly raised to the desired temperature with a minimum amount of heat. In this'and in other ways the tunnel is adapted to maintain a proper environment about the ware as it is passed thereth'rough. The temperature of this environment and of the ware as it passes through the tunnel is controlled in part by a counter-current of coollng air. The thermal properties of the tunnel, especially at its hot end, arev made more efiicient by making int'erior surfaces of that end of the tunnel of bright reflecting material. v

The ware is carried through the tunnel by an endless conveyor which is of low heat capacity and adapted to the desired thermal conditions. In returning to the hot end of the tunnel, this conveyor passes through the bottom of. the leer tunnel close to the ware, whereby the return strand when it again takes on the hot ware, is reheated to nearly the temperature of that ware, a factor which con-.

tributes to the proper maintenance ofthe desired thermal conditions in the tunnel. The tunnel is made adjustable in crosssection to suit the size of the were being made, as well as to secure other desirable advantages to be described. The leer is made of separableunit sections placed end to end to form the tunnel, and provisions are made for taking care of the expansion and contractionof the parts most subjected to heat. There are various structural features which contribute to the maintenance of such proper heat conditions, such as low heat capacity of the tunnel walls and parts, efficient heat-transference, heatbalance of the bearing strand andreturning strand of the conveyor chain, and maintenance of proper temperatures and temperature gradients. These features, as well as additional features to be hereinafter pointed out, will best be understood from the following description, together with the drawings, in which 2-- Figures 1 and 2 are side views, which taken together show a central longitudinal section through the receiving and the discharging ends of the leer, it being understood that these ends are or may be connected by any desired length of similar construction;

Fig. 3 is a transverse section through one of the leer sections, as on the line 33 of Fig. 1;

Fig. 4 is an enlarged side View in section accompanying in the same plane as Figs. 1 and 2, showing the expansion joint in the bottom of the leer; and

Fig. 5. is an enlarged plan view, in section on the line 5-5 of Fig. 1.

Fig. 6 is a diagrammatic plan illustrating the flow of air around the ware.

The leer may be, and for general use, preferably is made up of a series of unit sections placed end to end, for convenience in manufacture, shipment and installation. It further enables any desired length of leer to be built up from standard unit sections.

'It also enables the length of a leer to be 7 carry depending angle irons 11, by which they may be connected in abutting relation by suitable bolts or other connections. The lower ends of the'angle irons 11 are bolted section. The top 21, preferably made ad-- to the channel irons 10, as shown in Figs. 1, and 2. i

The walls of the tunnel formed by sections 7 and 12 are made of an outer casing of sheet metal or other suitable material, an inner lining of sheet metal as thin as is consistent with the strength required, and an intermediate filling of heat insulation. The thin sheet metal linings may be quickly heated upto their final working temperature with a minimum amount of heat, since their heat capacity is very low. The insulation outside of these linings reduces their dissipation of heat to the outside, so as to require only a 7 minimum of heat to maintain any portion of the leer tunnel at the desired temperature. Each section 7 and 12, as viewed in crosssection in Fig. 3, comprises a horizontal bottom wall with vertical walls at each side, closed by a top plate. The vertical side walls and bottom form a channel which comprises an outside casing 17 which is spaced from a bottom lining 16 and side linings 15 by transverse Stays 18 (Figs. 4; and two of which may form ends for the walls of the justable, consists of a sheet metal casing and a lining 23. The casing 17 and the linings 15, 16 and 23 are made of thin sheet metal. The spaces between the lining 23 and the casing 22, and between the linings and 16 and the casing '17, are filled with heat insulating material 19, which is preferably a loose material of high insulating efficiency and with a low heat capacity, such, for instance, as kieselguhr or mineral wool, The top of each tunnel section is closed by a cover plate 20 which prevents leakage of air. The sheets of metal forming the casings and linings and the top plate may be fastened together in any of the ways well known to sheet metal workers.

' In order'to better control the air currents and to increase the efliciencv of rad ation and reflection throughout the cross-sect1on of the tunnel, its cross-sectional area may be adjustthe fact that in different commercial ware thereis more variation in height than in width, and also because itis important to control the circulation ofthe air between the. were and the top of the tunnel, I prefer to make the to tunnel sections also to assist in controlling the currents of .1 and 2) may be provided in these tops and also in the cover plate 20 for the insertion or ceilingwalls 21 of the. and 12 adjustable verticaL. ly between the side walls thereof, to suit the height of the were being annealed, and

masses of a thermometer, and these; opening may, h closed when not in use. 1

The device for supporting and adjusting the top comprises studs 26 fixed in the top 21 and projecting through holes in the late 20, and in the re-inforcmg bars 27 an 28,

(Fig. 3) hand nuts 29 bein threaded on the studs. One stud is provide near each end of the top, so that the height of the top may be adjusted independently at either end, and it may be set at an angle or horizontally, as desired. In order to'facilitate adjustment of the top so as to insure that it will clear the ware to an extent determinable from the outside, means are provided outside of the tunnel for indicating the position of the top. For this purpose, the studs 26 are made of such length that their projection above the top of the hand nuts 29 is equal to the dis.- tance from the upper surface of the conveyor to the lowest part of the top. By this construction the top may be adjusted to the desired height by setting apiece of the ware on each nut 29 and turning the nut until the end of the stud 26 projects above the top of the nut a distance equal to the clearance desired over the ware in that portion of the tunnel, as indicated in Fig, 2. A graduated indicating device operating in a similar manner may be fastened to the top, if desired. By setting the adjustable top down fairly close to the top of the ware, the cross-sectional area of the tunnel and the space to be heated are reduced, the air currents are confined closer .to and directed between different articles,

and the heat reflecting and radiating efi'ects of the tunnelwalls are also increased.

In addition to the height adjustment for the tops 21-, some or all of them maybe provided with means for controlling a flow of air from the cold end toward the hot end of the leer tunnel. For this purpose the righthand end of the top of each section 7, as viewed in Figs. 1 and 2, is curved so as to form a transversely extending deflector 30 to intercept a part of the air passingthrough the tunnel, and divert it into a stack 31 which extends across the entire width of the tunnel.

By means of this construction. the hot air or other ases passing through the tunnel may be wit drawn therefrom in uniform quantities transversely thereof, thus insuring a uniform temperature across the tunnel. The tops are made thinner at one end sothat the deflectors on one top may project below the adjacent thinner end of the next top. (Figs. 1 and 2). The stacks 31 are supported on the LOO Ill

plates 20 with their lower ends extending into the tunnel between the ends of adjacenttops 21'. Eachstack 31 is provided with a damper 32 by which the escape of air may be regulated. The top for the delivery section 12 also'has a deflector 52 (Fig. 2)'at its righthand end todivert air to a stack 53, prov ded with an adjustable damper 54. 'By reason of the fact that the deflector 52 is farther away from the end of the top than in the other tops; that the right-hand end of the top is modified in shape as shown in the drawing; and that the stack 53 is larger than the stacks 31, a greater quantity of air may be diverted by-the deflector 52 and stack 53 than is diverted by the other deflectors and stacks. At the right-hand end of the deli ery section 12, a Wall 56 is fixed so that vertical adjustment of the top causes the deflector 52 to project more orv less below the wall 56, thereby in- The chains themselves form the conveying surface and are sufliciently strong to do their work while having a minimum mass and heat absorbing capacity. The chains are pulled through the leer by sprockets 36 .(Fig. 2) fixed on a shaft; 37 driven by a motor 38 through a chain 39, worm-and gear 40, and spur gears 41, 42 and 43. These gears may be made removable so that others may be substituted conveniently to change the speed of j the; conveyor. The chains pass'around a roll 46 (Fig. 1) at the receiving end, and idle rolls 47 are rovided where required to support and guide the chains.

As the ware-bearing strand of the conveyor moves from the hot end of the leer toward the cold, or discharge end thereof, it is progressively cooled. The return strand of chain travels back throu h the -heat enclosing tunnel and is progressively reheated, arriving at 'the receiving end of the leer at about the temperature of the ware received. In this way the ware-be'aring strand and return strand of the conveyor balance each other in their heat effect without disturbing the desired conditions in the leer tunnel.

There are 15 of the chains 35 shown in Fig. 3, but this number may be varied, as desired. The lower or idle strands of the chain return through the space or spaces betweenthe bottom lining 16 and. the upper or ware conveying strands, which are supported in close proximity thereto by sheet metal plates or tables 47. This construction excludes air currents from the space 45, thereby maintaining the heat in the lower part of the tunnel and assisting in the maintenance of uniform heat conditions throu hout any cross-section of the tunnel. The ta les 47 are made of thin sheet metal to reduce their heat capacity and of the chain underneath, thereby carrying out through the leer by a the heat balancing process above described.

To strengthen and support the tables, and 'maintaln the space or spaces 45, the tables are provided with ribs or flanges 48.

The leer is rovided with expansion joints to permit, an er changes of temperature, the I free expansion and contraction of the tunnel walls and parts of the leer, and particularly of the inner linings of the tunnel and of other parts most exposed to heat." This is articularly desirable in a leer tunnel of t e type described where thin sheet metal is employed to form the walls and other parts. Such thin sheet metal warps and buckles easily under the influence of temperature changes, unless provisions are made to allow itto expand and contract freely. One of the features which permits free expansion and contraction of the various parts is the construction of the leer in a series of unit sections which are placed .end to end. Each of these sections 7 and 12 leer as a whole under the influence of heat, and distributing the expansion and contraction over several joints. The tables 47, side "linings 15 and bottom linings 16 are provided with expansion joints indicated at 49 on Figs. 1 and 2. The joints are formed by folding back adjacent marginal edges 50 (Figs. 4'and 5) of the linings and tables and connecting the parts .by strips 51 having similar turnedover edges loosely embracing the edges 50. These expansion joints are shown as positioned near the middle of eachsection', but

they may be positioned at the end of each section or at both places if desired. Similar expansion joints may be' provided in the outer casing '17, although thisjis not considered essential, as that casing remains relatively cool on account of its insulation. The various sectional tops 21 are separated in a manner which would not usually require expansion joints, but theyfmay be provided with similar expansion joints, if -desired. The transverse stays 18 are sufficiently flexible to permit their inner edges to move with the tunnel linings as the latter expand or contract.

I In order to control the cooling of the ware as it moves toward the discharge end of the leer, cooling air is forced into the leer tunnel near the discharge end thereof, suitablemeans being provided for furnishing a controllable supply of air ofthe desired volume and pressure, which flows from the discharge or colder end of the leer toward its hotter end.' A blower 57 (Fig. 2) driven by a motor 58 is arranged to force air through a wind box 59 which directs the air against the glassware and into the tunnel. An adjustable damper.

60 is provided to r'egulatethe amount of air discharged by the blower. The air is directed in width toward the hot end of the tunnel and formed by a series of flanges on the bottom wall. of the wind box. The volume of air entering the tunnel is controlled by the damper 60 and the air passing through different portions of the tunnel is regulated by adjusting the dampers 54 and 32, and by adjusting the height of various tops 21. The air discharged from the wind box 59 is first directed against the colder ware which has emerged from the tunnel, so as to give it its final cooling at a certain portion of rapid rate. The air then flows between the various pieces of ware and enters the tunnel, the direction of flow being indicated by the short arrows in Fi 2'. At about that portion of the tunnel w ere the ware is cooled to about 300 F. a large part of this air is diverted by the deflector 52 and escapes up the stack 53. The remainder of the air continues to flow toward the hot end of the tunnel and is forced to flow between and around the pieces of were by the low position of the tops 21. As the air approaches the next deflector 30-, the gradually increasing space above the ware, due to the slope ofrt e top, permits a the hotter air to rise and flow above the ware, and it is diverted by deflezctor 30 and escapes up the stack 31. In this way the air flows along the tunnel toward the hot end, becoming progressively hotter by its absorption of heat from the were and the tunnel walls, a determinable portion being diverted by each deflector and escaping up the corresponding stack. Only a very small portion of the an reaches the hot end of the tunnel. It is preferable, however. and highly advantageous to maintain a suthcient pressure of air toward the hot end of the tunnel to prevent outside cold air entering the hot end of the tunnel and flowing along it toward the cold end.

By setting the adjustable tops 21 at the proper height and ad uSting the various stack dampers',-as'wel1 as by supplying asu'fficient amount of'ceoling air from the nozzles 61. the amount of air passing at various points throughout the length of the leer tunnel may be regulated, and the temperature of the We re as it moves through the leer may be controlled as desired. With a proper setting of these various parts anda prr supply of cooling air, the latter is force '1 to circulate between the glass articles as well as along the linings of the leer tunnel in acontrollable volume. It

the air passing along any portion of a transverse section of the leer tunnel. becomes hotter than it is in other portions of that section it tends to rise into the adjustable space above the ware and tobe diverted into, a stack besides having portions of its heat. radiated and reflected across the tunnel by the tunnel walls. This assists in keeping the temperature uniform throughout any transverse section.

'cient annealing may be The cooling air'not only cools the were directly, but it also cools it indirectly by cooling the linings of the tunnel. The were radiates heat to the linings of the tunnel which, a being surrounded by heat insulation, tend to acquire the temperature of the successively passing pieces of ware, and would thus acquire a temperature only very slightly below that of the ware were it not for the cooling air which absorbs heat from these linings? maintaining them at a suitably lower temperature than that of the adjacent ware, thus maintainingthe desired temperature gradient to control the rate of radiation of heat from the were to the linings.

The cooling air gradually becomes hotter as it progresses from the cold end toward the hot end of the leer, so that there is at no time an abrupt or injurious diiierence bf temperature between the cooling air and the. were, 5 or between the cool in air and the linings at any transverse zone 0? the leer tunnel;

The rate at which the ware is cooled is an important factor and contributes to the speed, and perfection of annealing. If the drop in g temperature throughout the greater portion of the length of the leer is substantially uniform for each unit of len th, the most e'flidhne ver rapidly. Although, as previously indicated: the rate as of cooling for some kinds of ware or some kinds of glass may be increased after it passes through the critical range of cooling temperature, I prefer for safetyi, to continue, the uniform rate of cooling suitable for that" ice critical range. down to a temperature of about 300 degrees F., from which point the, ware may be very rapidly cooled, by subjecting the ware to a large volume of cooling airfrom the nozzles 61 at the cold end of thelcer cool- 1 ing the ware rapidly to a safe handling temperature, .the excess volume of air being then diverted, as above described;

To obtain thev uniform cooling of the were. in uniform units of length of the leer, the ""i temperature gradient or differential-between the cooling air and the tunnel linings,,es Well as between the cooling air and the-ware may be maintained substantially uniform tlirou 'hout the desired length of the leer. The 1a gram shown in Fig. 6 illustrates the principle here referred to, using assumed temperatures. it shows three different transverse zones B, C and D in the length of the leer, the tiow of air being indicated by arrows. In zeneB the temperature of the ware might 800 FL, while the temperature of the air might be 7 50 1*. Under these conditions the temperature of the adjacent leer walls might be, somewhere near 7 75 F. In zone C, the tetii perature of the ware'might be 700 F, and the temperature of the airpaming morgst the ware might be 650 F, Wllllefth canesponding temperature of the adiaeent leer, wallamight be 67 5 in zone D, the temperature of the ware might be 600 F. while the air might be 550 F. and the adjacent walls 175 F. In each instance there is or may be a uniform differential of 50 between the air and the ware; a uniform differential of 25 between the air and the walls, and a uniform differential of 25 between the walls and the ware. By maintaining a uniform rising temperature gradient of the air as it flows toward the hot end of the leer, a uniform falling temperature gradient will be maintained in the ware as it moves towards the cold end of the leer.

In Fig. 6 the ware is for convenience of illustration shown arranged in transverse rows at right angles to the side walls of the deer. The principle is the same, however, when the ware is staggered or in inclined rows. The temperature gradient in any transverse zone equal to the width of an article is not sufliciently abrupt to cause stresses between the leading side and the following side of the same article while passing through any of the zones.

In order to approximate as closely as possible in this leerthe ideal cooling conditions, it would be preferable to carry the articles to be annealed through the leer tunnel in single file. This, however, would require an incon- 30 veniently long tunnel, in order to take care of the large commercial production of the average automatic shaping machine and yet provide the proper cooling conditions. To

' avoid this I carry the articles through the leer preferably not more than three. This allows a sufiiciently equal radiating effect between the articles in each row and the wall linings of the leer tunnel, so that all the articles and all parts thereof are subjected to substantiallythe same heat conditions. Ifany article or any portion of any article, should be at a lower-temperature than other portions or than other articles in the same transverse zone of the leer, or the adjacent linings of the tunnel walls, then the hotter articles or hotter portions of the same article and of the tunnel linings will radiate and reflect sufficient heat to equalize the temperature, thus constantly tending to avoid such differences and to correct them. automatically when they occur.

The reflection of heat from the linings of the tunnel walls, whether to the articles or by making these linings of metal having For such heat reflecting surfaces, thelinin'gs of the tunnel walls may be made of various suitable materials, preferably material capableof maintaining a bright reflecting surface at, the comparatively high "temperature to which'itis exposed. For this purpose, the 1inings of the hotter portion of the tunnel may tunnel in several longitudinal rows or files,

from wall to wall may be increased if desired 'bensed, If L esired, a mu'ffle form of firebox be made 'of shhet nickel which will stand the working temperature without corroding, thus maintaining the necessary brightness, and may be obtained in sheet form sufficiently thin to serve the other purposes above described.

By means of the above described features, such as tunnel wall construction, which provide for proper insulation, radiation and reflection of heat; the adjustable top onwall, which may be set close to the ware to reduce the crosssection of the tunnel and assist in controlling thel flow of cooling air; the even cooling effect on the leer walls and on the ware producedby the controlled cooling air, '80 the temperatur of the ware throughout any transverse sect on or zone of the tunnel is made so nearly uniform as to approximate the ideal envir ment. The temperature in any transverse one of the tunnel is substantially the same 11 the top, bottom, sides and corners of that zone.

' Thus, as the articles pass through the successive zones of the tunnel they have or acquire the progressively falling temperatures; of those zones,and all portionsofeve'ry article passing through any zone acquire approximately the temperature of that zone with sufficient uniformity for practical annealing. By this apparatus and method average glass. articles may be annealed in a very short time, requiring only from 30 to 45 minutes for the annealing and final cooling, as against the usual time of two to five hours required by the best previous commercial annealing leers.;

By this method and apparatus most commercial glassware may be annealed entirely by its own heat, without the necessity of reheating the ware by supplying additional heat to the lee: if the ware is placed in the receiving end of the leer soon after its removal from the mold, so that it still retains as a whole the necessary amount .of heat for the purpose, even if not then uniformly distributed throughout each article.

There are, however, some articles made which even when removed from the shaping machine and placed in the leer in the shortest possible time, do .not carry sufficient heat into the leer to accomplish proper annealing, as above described, without the supply of additional heat. It may also sometimes be desirable in the treatment of the ware to have articles cooled down before placing them in the leer to a point where they do not contain I sufficient heat for such annealing.- In both bright polished surfaces WlllCh "reflect a larger portion of the heat radiated to them,

these instances, additional heating means may be supplied to the leer for-the purposeof attaining the desired temperature of the ware and of the leer tunnel at its hot end.

ments may be provided to fire-boxof anwell-knownconstruction may 1") may be. employed, so that the receiving end of the leer is surrounded by a heating jacket instead of by insulation, although if desired insulation may also be employed outside of the mufiie fire box. Such heating means will only be needed at the hotter end of the leer, the action of the remaining length of the leer being as above described.

In starting operation with a cold leer some pre-heating of the tunnel and conveyor may be desirable, even though it may not be necessary to continue its use after normal heat conditions are established in the leer. This initial pre-heating may be done by means of burner or other heating elements for the tunnel as above suggested, or in some instances it ma be sufiicient to preheat the conveyor by a urner 62 or other means disposed beneath the idle strand of the conveyor at the receiving end of the leer. The heat carried in by the conveyor may also be used to preheat the tunnel.

The leer may also be thus preheated initially by passing through it the imperfect ware usually made when starting up the associated shapingmachine, until the various molds and molding parts of the shaping machine have been raised to the proper normal working temperature. By the time the shaping machine is producing perfect ware, which sometimes takes as long as twenty minutes to attain, the temperature throughout the leer will usually be suflicient so that as soon as perfect ware passes into the leer it will be properly annealed without additional heat.

There are, however, some kinds of ware which may be-delivered from the shaping machine into the cold leer, and the leer thus started in continuous operation without preheating it, whereupon the various parts of the leer tunnel will soon reach their proper working temperature and the articles will emerge at the discharge end of the leer tunnel properly annealed. In any of the above methods of initial preheating the cooling air supply need not be turned on until the ware approaches the discharge end of the leer, or until the proper temperatures have been attained in the tunnel.

The features above described, of this invention, relate mainly to its annealing func- 'tions. In addition thereto, it has other more general advantages as compared with existing methods and apparatus. lhe leer is of light weight and low initial cost. Instead of being built up by hand labor, in the plant where it is to be used it may be manufactured complete in a machine shop wherever desired and in quantity production, using jigs and fixtures to facilitate the work and to make its parts interchangeable. It may be made in unit sections of convenient length for handling and transportation. It may be transported anywhere and erected by unskilled labor. It requires no masonry foundations or expensive piping or other adjuncts. It therefore requires for its installation no extensive preparations in a new plant, or ex- Aresultant advantage of this rapid an-' nealing is that the ware passes through the leer and can be inspected in considerably less than an hour, so that faults due to the molds or other features of the shaping machine can at once be detected and the wastage stopped, thus increasing the saleable production. Moreover, the were made up to the end of a day can be inspected and packed within an hour after shutting down the shaping machine, instead of requiring several hours, and sometimes an additional shift on Sundays to inspect the ware made the previous day.

The light construction and mobility of this leer enables its position to be changed whenever or wherever desired. When" made. of a capacity suitable for annealing the ware made by a single shapin machine, it may. be

moved close to that mac ine so that the takeout boy can transfer the ware directly from the moldsinto theend of the leer, thus saving the services of a carrying-in boy, and savingthe breakage of were by him, which is often very great. Setting the leer'close to the shaping machine also avoids the loss of heat by the ware. The leer is also well adapted for receiving the ware from an automatic conveyoror stacker, or directly from heat by the were. The leer is also well out of the molds. The method and means employed for conserving and utilizing the heat of the ware, and equalizing that heat throughout the ware by radiation and reflection, minimizes the use of fuel and the cost of firing attendance, both'of these being avoided altogether in cases where the character of the ware permits it to be annealed by its own heat.

Repairs when needed may be easily effected. When extensive repairs are needed the le'er may be removed entirely and another leer substituted in a very short time, and with a minimum of interruption in the production of the shaping machine.

The various features of the invention herements and other provisions for handling varied kinds of ware may be dispensed with. The leer tunnel may be made integral throughout its length. 7 In this and in other ways the method and apparatus herein described and shown may be modified with-in the scope of the appended claims.

Certain features disclosed inthis application are not herein claimed, but are reserved for my divisional application, Ser. No. 278,- 849, filed May 18, 1928, wherein I claim certain features which are not claimed in the present application, particularly the characteristic arrangement of the conveyor and the characteristic combination of an external rigid support and a tunnel of non-rigid construction.

I claim: 1. A lehr having a tunnel, means for moving the ware through the tunnel, a pluralit v of stacks arranged at intervals longitudina ly of said tunnel for varying the temperature in the tunnel longitudinally thereof, and

means to permit independent adjustment of the cross-sectional areas of various portions of the tunnel, whereby to selectively control the amount of gases passing out the several stacks and consequentl to selectively control the rate of cooling of the ware throughout selected portions of the tunnel.

2. A lehr comprising side and bottom wall 7 members and a top wall member forming a tunnel, at least one of said members being divided longitudinally of the tunnel into a plurality of portions, means for moving the ware through the tunnel, a plurality of stacks arranged at intervals lon itudinally of the tunnel, each associated wit one of said portions for controlling the tem eratures in the tunnel longitudinally thereo and means to permit independent adjustment of said 1101'- tions to vary the cross-sectional areas ofthe tunnel throughout selected zones whereby to selectively control the amount of gases passing out the several stacks and consequently to selectively control the rate of coolin of the wrtre throughout selected portions of t e tunne a I a 3. A leer comprising side and bottom walls and a top forming a tunnel, means for moving the ware through the tunnel, and means a .to permit independent adjustment of the cross sectional area of the tunnel at different points in its length. a

. 4. A leer having in combination, side and bottom walls'formin three sides of a tunnel, and a plurality 0 independently adjustable sections forming a top for the tunnel.

5. A leer for annealing glassware, comprising a channel-shaped member forming the bottom and two side walls, a cover sup ported by the side walls, a top suspended benea'th the cover, and means to perm1t-vert1- cal adjustment of the top.

justable means for regulating the escape of tunnel, a plurality of independently vertimovement of said glass," an

arate zones longitudinally of the tunnel by I r111 v ijng a'cover,-'s1de walls and a ottomlwall, a

-'therethrough, means for blowing air into the ware discharge end of the tunnel, and adair from different points in the length of the tunnel. v 7. A tunnel lehr for annealing glassware, comprising bottom and sides of an elongate cally adjustable sections forming the top of the tunnel and extendin between the sides substantially end to en longitudinally of said tunnel, means to cause a gaseous fluid to flow longitudinally through said tunnel, one end of each of said to sections being formed as a deflector for said fluid, an outlet from said tunnel adjacent to each of said deflectors, and eans relatively to adjust the adjacent ends of contiguous to sections vertically, whereby to controlt e amount of said fluid directed out said outlets by said deflectors. i k v y 8. Thev method of annealing glassware, which comprises continuously passing glass through av tunnel lehr, passing air through said tunnel inadirection op osite to the controllably varying the rate of cooling throughout sepcontrollably and independently regulating cross sections of the several zones. I

' 9, In a tunnel lehr for an aling glassware having .walls sealed against transverse leak-v ageof air and having an inlet end and anoutwe let end, means for- -movmg the glassware through the lehr from the inlet end to the outlet end and an additional longitudinal wall within said lehr adjustable to diflerent positions relative to one of said first named tunnel wal s.

' 10. In a lehr for ann ealing lassware having a cover, side walls and a ott om wall a vertically movable false top with n the sa d lehr,- for limiting the effective height of the no lehr. a v r a a a lehrforflannealing lassware havvertically .movable insulated fals'e top within said lehr, for limiting the eflective height of the lehr.

12. A lehr for annealing glassware comprising a tunnel having a plurality 0 movable top sections, and means for varying the angular inclination of said top sections to 12 regulably control the escape of air from the tunnel.

13. A lehr for annealing glassware,comprising a tunnel having a plurality of IIIOV! able top sections, and means for independently varying the angular inclination of each'of said top sections,.whereby to regulably control independently the escape of air at va-- rious points along said tunnel.

' 141A lehr for annealing glassware, comprising a tunnel. having a movable top section, said section forming with adjacent parts of the tunnel an outlet for the hot gases from the tunnel when said section is inclined with respect to the horizontal, and means for adjnsti'ng the angular inclination of said top section to vary the eifective area of said out- =15. A lehr for annealing glassware, coniri'sin'g a tunnel having a top having a pinr'ality of inclined surfaces, means for adjusting the inclination of the surfaces, and openings commnnicatingwith the atmosphere at the npper end of each of said inclined sur faces.

1 6.'In a glass annealing l'ehr of the tunnel type, an elongate tunnel, a continuous conveyor adapted to transport glassware through. the tunnel, means for blowing air downwardly into the tunnel and toward the ware re'ceivin end thereof', and means located at space intervals along the tunnel for independently and regulably removing portions of the air from the tunnel.

17. in a lehr for annealing glassware, an

elongate t'l'lnnel, means for moving the ware therethrough, and means for controlling the How 'of air throngh the tunnel, said last named means comprising means for blowing a regnlable amount of air into the ware-discharge end of the tunnel, and independently regulable means for drawin 0E air; from the tnnnel at a point adjacent t e discharge end thereof.

' 18. For a tunnel lehr having walls sealed against transverseleaka'ge oi 'air, an auxil- 'iary top within said le'hr adjustalale to different heights, and traitisverse paltitions "ne- 'tvvee'n said anxili'ary topandthe top'oi the tunnel lehr having a fixed wall and an auxiliary wefilajdfacent to said fixed wall,

, one of said walls te'ing'of light construction relative to the other of said walls, the 'anixi'lia'ry well being readily adjustable to difierent positions relative to the fixed wall.

g 'da't Hartford, nonmcncat, this em nyof September, 1923."

v vnncrifn MULHQLLAND.

"ijrsteea CERTIFICATE or CORRECTION.

Patent No. 1,135, 353. 4 Granted November 12. 1929, to

venom MULHOLLAND.

It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction as follows: Page 7, line 3, for "175" read "575 page 8, lines 106 and 107, strike out "heat by the ware. The leeris also well out of the molds" and insert instead "an automatic take-out for taking the wareout of the molds"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 3rd day of December, A; D. 1929.

M. J. Moore,. (Seal) Acting Commissioner of Patents.

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