CONTROLLED COOLING APPARATUS AND METHOD FOR PROVIDING PREFERENTIAL COOLING OR HEATING IN A CONTINUOUS GLASS RIBBON - Patent application

Abstract

A glass ribbon processing apparatus for producing a glass ribbon of varying thickness includes a first device that cools a first portion of a width of the glass ribbon at a different rate than a second portion of the width of the glass ribbon, the first portion being thicker than the second portion.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Patent Application No. 63 / 295,137, filed December 30, 2021, the contents of which are relied upon and incorporated herein by reference in its entirety. [Technical field]

[0002] The present disclosure relates to a controlled cooling apparatus and method for providing preferential cooling or heating within a continuous glass ribbon. The disclosed apparatus and method can be provided as a modification to existing glass processes or can be used in new designs for producing glass products. [Background technology]

[0003] When a glass body for a particular smartphone and mobile device back cover, or electronic component or housing design, has a non-uniform thickness, the non-uniform thickness being thicker in the camera area than in other areas, the design of the camera lens can be improved (see, for example, Patent Document 1). As an example, the glass thickness can be 1.5-3.0 mm in the thick areas and less than 0.8 mm in other areas. To manufacture the thick areas for the back cover or housing of the device, a relatively thick glass sheet can be ground, lapped, and polished to define the thick and thin areas. In such a case, a glass sheet having a thickness of 1.9 mm can be used to make a glass article having a nominal thickness of 1.6 mm in the thick areas and 0.6 mm in other areas. That is, 0.3 mm of material would be removed from the thick areas and 1.3 mm of material would be removed from the other thin areas. This approach has poor glass utilization, is time-consuming, costly, inefficient, and environmentally unfriendly.

[0004] An alternative method for forming glass articles of non-uniform thickness could be to fuse two glass substrates (see, for example, U.S. Patent No. 5,339,933). For example, a 25 mm×25 mm×1.0 mm piece of glass could be fused to a larger 70 mm×150 mm×0.6 mm piece of glass by gluing or pressing at high temperature. This method improves glass utilization, but is energy intensive, can lead to bubble formation at the fusion interface, and can be costly and more time consuming. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US Patent Application Publication No. 2019 / 0364179 [Patent Document 2] US Patent Application Publication No. 2017 / 0210111 Summary of the Invention [Problem to be solved by the invention]

[0006] If the grinding process is not cost-effective and generates too much waste, and if fusing two pieces of glass is not a viable option, another solution is to define a continuous glass ribbon with the desired thickness difference. To produce a glass ribbon with varying thickness, it may be necessary to generate a large temperature difference between the thick and thin portions. Therefore, to produce such a glass ribbon with reduced stress and warpage, the ability to preferentially cool the thick portions at a predetermined rate that is different from the cooling rate of the base ribbon (or the thin portions of the glass ribbon) is required.

[0007] The present disclosure provides a solution to this technical problem. [Means for solving the problem]

[0008] To overcome the above problems, embodiments of the present disclosure provide an apparatus and method for minimizing stress and warpage in glass sheets of varying thickness by managing temperature gradients from thick to thin and from top to bottom, thereby cooling thicker portions of the glass ribbon at a faster rate than thinner portions. Cooling can be accomplished from the top and / or bottom of the glass ribbon through convection and / or radiation. Optionally, localized heating can be used in conjunction with preferential cooling to control desired temperature parameters within the glass.

[0009] The described embodiments can be applied to Controlled Cooling Apparatus (CCA), which is an advanced lehr, or a roller hearth lehr, or a roller kiln, that produces glass ribbons. The present disclosure provides a solution to the thermal management challenges that must be overcome to produce glass ribbons of varying thickness.

[0010] Without the presently described thermal management methods, the stresses induced in the glass ribbon of varying thickness would be too high, which would require scoring the sheet, cutting the high stress areas from the sheet, or additional finishing processes to fabricate the glass to the desired size, shape, and thickness. Alternative methods to reduce the stress in the glass ribbon would include significantly increasing the length of the annealing furnace or adding an annealing step, both of which require significant cost and space.

[0011] According to one embodiment of the present disclosure, a glass ribbon processing apparatus for producing a glass ribbon of varying thickness includes a first device for cooling a first portion of a width of the glass ribbon at a different rate than a second portion of the width of the glass ribbon, where the first portion is thicker than the second portion.

[0012] In one embodiment, the first device is positioned above or below the glass ribbon and near the glass ribbon. In one embodiment, the first device is a heat exchanger that extracts heat from the first portion. In one embodiment, the first device pushes air into the first portion. In one embodiment, the first device is configured to extract heat from the first portion and push air into the first portion. In one embodiment, the first device comprises a valve that regulates the air pushed into the first portion. In one embodiment, the first device comprises a heater.

[0013] The glass ribbon processing apparatus can further include a second device for heating any portion of the width of the glass ribbon.

[0014] In one embodiment, the second device heats the interface between the first and second portions.

[0015] In one embodiment, the first device is a plurality of first devices configured to be aligned within the apparatus.

[0016] The glass ribbon processing apparatus can further include a section heater including at least two heating zones for applying a heat treatment to the glass ribbon.

[0017] According to one embodiment of the present disclosure, a method of producing a glass ribbon of varying thickness includes conveying a glass ribbon and cooling a first portion of a width of the glass ribbon at a different rate than a second portion of the width of the glass ribbon, where the first portion is thicker than the second portion.

[0018] In the method, cooling is provided by a device located above or below and near the glass ribbon. In one embodiment, cooling is provided by a heat exchanger that extracts heat from the first portion. In one embodiment, cooling is by air forced into the first portion.

[0019] In the method, a first device is configured to extract heat from the first portion and push air toward the first portion. In the method, the first device heats the glass ribbon.

[0020] The method may further include heating the interface between the first portion and the second portion.

[0021] The method may further include heating the width of the glass ribbon in sections.

[0022] The above and other features, elements, characteristics, steps, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the present invention taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0023] [Figure 1A] FIG. 1 is a diagram showing an example of the shape of a glass ribbon. [Figure 1B] FIG. 1 is a diagram showing an example of the shape of a glass ribbon. [Figure 1C] FIG. 1 is a diagram showing an example of the shape of a glass ribbon. [Diagram 2] Graph showing baseline cooling curves for glass ribbons of varying thickness [Figure 3A] Graph showing cooling curve of glass ribbon [Figure 3B] Graph showing cooling curve of glass ribbon [Figure 4] A diagram showing a cross-sectional model of a controlled cooling device. [Figure 5A] Controlled cooling device images [Figure 5B] Controlled cooling device images [Figure 6] Stress and warpage data versus cooling flow rate [Figure 7] Diagram showing the radiating member [Figure 8] Diagram showing composite material [Figure 9] Diagram showing air box with strip heaters [Figure 10A]Model showing the effect of airflow from the airbox [Figure 10B] Model showing the effect of airflow from the airbox [Figure 11A] Diagram showing the cooling effect on a thick part of the glass ribbon [Figure 11B] Diagram showing the cooling effect on a thick part of the glass ribbon [Figure 12A] Cross-sections of various configurations of controlled cooling tunnels [Figure 12B] Cross-sections of various configurations of controlled cooling tunnels [Figure 13A] Cross-sections of various configurations of controlled cooling tunnels [Figure 13B] Cross-sections of various configurations of controlled cooling tunnels [Figure 14] Cross-sections of various configurations of controlled cooling tunnels [Figure 15] Cross-sections of various configurations of controlled cooling tunnels [Figure 16] Cross-sections of various configurations of controlled cooling tunnels DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] 1A-1C are examples of glass ribbon shapes made possible by the apparatus and methods described in this disclosure. The shapes shown do not reflect all possible shapes and are designed for specific products.

[0025] In Figures 1A-1C, the light blue areas represent the base ribbon or thin sections and the dark blue areas represent the thick sections. Figure 1A represents a glass ribbon with an overall width of 180-230 mm. The thick sections are shown as having a width of 40-55 mm starting 20-30 mm from the left edge of the glass ribbon and with their centers located 40-65 mm from the center of the glass ribbon.

[0026] 1B depicts a glass ribbon having an overall width of 300-400 mm. The thicker portion is shown to have a width of 180-110 mm and is located approximately in the center of the glass ribbon.

[0027] 1C depicts a glass ribbon having an overall width of 300-400 mm that includes two thicker sections having widths of 40-55 mm, one thicker section located 0-30 mm from the left edge of the glass ribbon and the other thicker section located equidistant from the right edge of the glass ribbon.

[0028] [Table 1]

[0029] Table 1 includes some example parameters that indicate the possible range of thickness values ​​for the tapered portion of the glass ribbon. Items 1-3 show that glass ribbons having a perfectly uniform thickness are also possible.

[0030] FIG. 2 is a graph showing a baseline cooling curve for a variable thickness glass ribbon product with a base glass thickness of 2.0 mm and a delta thickness change of 0.3 mm for the center strip in the CCA. This cooling curve data was obtained and modeled in an initial production test of a variable thickness glass ribbon with no preferred thermal management tools or techniques in the CCA; that is, the CCA had a standard equipment setup using only SiSiC plates for radiative cooling of the entire glass ribbon. See FIG. 4, which shows a portion of the CCA including SiSiC plates. SiSiC plates have a low coefficient of thermal expansion (CTE) and high thermal conductivity, making them well suited to provide a uniform radiative heat source above the glass ribbon in the CCA tunnel.

[0031] FIG. 2 plots the temperature of the glass ribbon on the left vertical axis versus the distance in the CCA tunnel on the horizontal axis for the conventional process. The red curve is a model of the centerline temperature of the top surface (A-side) of the thick section. As shown in the figure, the temperature of the thick section was 700° C. at the CCA inlet and 556° C. at the CCA exit. The blue curve is a model of the temperature of the thin base glass. As shown in the figure, the temperature of the thin section was 660° C. at the CCA inlet and 546° C. at the CCA exit. The grey diamond shaped data points (CCA SP) represent the temperature set points of the SiSiC plate at positions along the CCA tunnel. The grey curve is the temperature of the SiSiC plate passing through the set points. The black square data points and the values ​​shown are the actual pyrometric temperature of the glass ribbon measured through the SiSiC plate.

[0032] The dashed black line represents Delta T (DT), the modeled temperature difference between the thick and thin sections of the glass ribbon, plotted on the right vertical axis. The data reveals the expected mismatch in cooling rates between the thick and thin base sections of the glass ribbon.

[0033] With traditional thermal management within the CCA, the thicker sections are always hotter than the thinner base glass throughout the entire controlled cooling section. This persistent thermal gradient between the thicker and thinner sections present during ribbon cooling was managed fairly well by controlling the CCA SP for this low delta thickness product, but it did result in high stresses and warpage in the formed product. Subsequent testing has provided ample evidence of increased mass in the thicker sections and even worse thick-to-thin DT for products with higher delta thickness, suggesting an imminent need to install preferential thermal management tools within the CCA to lower the thermal gradients and mitigate the resulting stresses.

[0034] Figures 3A and 3B show modeled cooling curves of a glass ribbon, with the temperature of the glass ribbon on the left vertical axis and the distance to the CCA on the horizontal axis, comparing the process with preferential cooling. The glass ribbon is a 1.0 mm thick thin base glass and a central strip product with a delta thickness of 1.4 mm. The red curve is the centerline temperature of the thick section, and the blue curve is the centerline temperature of the thin base glass. The black areas are the CCA setpoint temperatures. Figures 3A and 3B compare the cooling curves of the same product with varying thicknesses, with two different CCA machine settings. Figure 3A shows the results of a conventional CCA machine without preferential cooling; i.e., SiSiC plates are used for controlled radiative heating and cooling of the entire glass ribbon. Figure 3B shows the results with preferential cooling, where an additional radiative cooling strip is placed 10 mm above the thick section of the glass ribbon for additional cooling. The dashed black curves in both figures plot the temperature difference (DT) between the thick and thin sections within the CCA. As can be seen, in both scenarios, the DT between the thick and thin parts is zero.

[0035] 3A and 3B demonstrate that the localized preferential cooling process within the CCA can minimize and approach zero DT between thick and thin areas throughout the controlled cooling section where stresses and warpage are most sensitive to thermal non-uniformities within the product due to the viscoelastic properties of the cooled glass.

[0036] In Figure 3A, the cooling curve of a glass ribbon product with a delta thickness of 1.4 mm in the controlled cooling section is shown, where the CCA is configured with a conventional equipment setting similar to that used to generate the data plotted in Figure 2. The different results are due to the different CCA set points and the difference in DT between the tests. Figure 3B shows the cooling curve of the same glass ribbon product and the same CCA setting including a local radiative cooling strip 10 mm above the thick section. Comparing the DT (value on the second y-axis) between the thick and thin sections of the two cases shown by the dashed black lines, a clear thermal effect can be seen between the process using conventional cooling and the process using the local preferential cooling strip.

[0037] As shown in FIG. 3A, due to the mismatch in cooling rates between the thick and thin sections in conventional cooling, the DT between the thick and thin sections increases cumulatively from the inlet to the outlet of the CCA. As shown in FIG. 3B, by using a process of placing cooling strips on the thick sections and optimizing the surface temperature with respect to the temperature of the SiSiC plate, the DT between the thick and thin sections can be minimized to zero in the CCA. It should be understood that the preferential thermal tool in the CCA is not limited to using this particular radiative cooling method or to cooling either side of the glass ribbon. In an embodiment, the preferential thermal tool may be a combination or sole use of convection and / or radiation on the top (A side) and / or bottom (B side) of the glass ribbon product.

[0038] The key element is that the preferential thermal tool provides additional cooling so that the glass ribbon achieves approximately the same temperature in the thick and thin sections and the DT between the thick and thin sections in the CCA is maintained near zero. One such preferential thermal tool for additional cooling of the thick sections is modeled in FIG. 4, and the cooling curve, CCA SP, and the temperature of the cooling strip (green curve) are shown in FIG. 3B. Preferential cooling of the thick sections of the glass ribbon can be combined with preferential heating of the thin sections, especially in modules or sections before the CCA, if the temperature of the thin sections is lower than a predetermined target value. Heating of the thin sections can be achieved by using local heating tools or by keeping the temperature of the entire CCA module higher than that of the thin sections (while the cooling tool preferentially cools the thin sections).

[0039] Figure 4 shows a conceptual model showing the equipment configuration for preferential cooling in a CCA. A portion of a glass ribbon of varying thickness is shown resting on a roller and being uniformly heated from above by radiation from a SiSiC plate. The white lattice structure below the roller represents insulation to help maintain efficient uniform heating. A uniformly temperature, actively cooled radiative cooling strip is placed 10 mm above the thick section located in the center of the glass ribbon to provide additional cooling to the thick section. The model shows a numerical proof of concept that preferential thermal tooling can be used to keep the DT between the thick and thin sections in a CCA to a minimum, which is key to minimizing stress and warpage in the formed product.

[0040] 5A and 5B are images of a CCA that has been modified to test the concept of preferentially cooling the thick central region of a continuous glass ribbon by forced convection. As shown in the images, an air box 500 is installed under roller 510, which allows an array of holes to deliver a flow of coolant air exactly where it is needed on the underside (B-side) of the glass ribbon. In this case, the box can be moved to the process left and / or process right to align them based on feedback provided by the birefringence map, as illustrated in FIG. 6. The available air supply is 0 to 35 scfm (0 to 59.5 m) at a speed of about 30 m / s, from a distance of about 0.5 inches (about 1.27 cm) from the back surface of the glass ribbon. 3 / hour).

[0041] A comparison of the cooling flow rate with the stress and warpage data in Figure 6 shows that as the thicker sections cool and the temperature difference between the thicker and thinner sections decreases, the stress in the glass ribbon also decreases. It should be noted from the data that the hole size, hole spacing, coverage, distance of the air box from the ribbon, and other geometric features can be optimized based on the particular application and desired results.

[0042] Cooling can be applied using any combination of forced air (convection) and radiation. The design of a cooling system includes consideration of factors such as emissivity, the ideal gas law, and the expansion of heated air, removal of heated air from the building, and safety of occupants. In some applications or temperature ranges where forcing air directly onto the glass ribbon is not necessary or desirable, forced air cooling can be combined with radiation or applied by radiation, by removing or completely eliminating holes from the air box, as shown in FIG. 7. For example, in the first third of the CCA where temperatures exceed 600° C., radiation can effectively produce a temperature drop while simultaneously reducing stress on the glass ribbon, while in the last two thirds of the CCA where temperatures are below 600° C., forced convection can be more beneficial.

[0043] 7 illustrates a design of a radiating member 700 used to cool the sides of a glass ribbon. Herein, the radiating member 700 includes an inlet 710 and an outlet 720 without any openings through which the air impinges on the glass ribbon. That is, the cooler air entering at the inlet 710 travels through passages and / or baffles in the radiating member 700 and exits at the outlet 720 at a higher temperature, extracting heat from the radiating member 700 that was absorbed due to its proximity to the hotter glass ribbon. Any coolant other than air can be used as a heat exchanger to remove heat from the radiating member 700 entering at the inlet 710 and exiting at the outlet 720, such as, for example, a suitable gas, water, or another suitable liquid.

[0044] Alternatively, the CCA may be provided with a composite dual mode cooling member. For example, as shown in FIG. 8, a composite member 800 may be configured to provide convective and / or radiative cooling at different times or at different locations on the composite member 800. As an airbox, the composite member 800 may include nozzles or outlets 820 that direct air to the glass ribbon at the exact location where enhanced cooling is required. When less intense cooling is required, the composite member 800 may be valved (manually or electromechanically) to close the nozzles 820 and enter radiative cooling mode.

[0045] FIG. 8 illustrates that composite member 800 may include two air inlets. A conventional air inlet 810 provides convective cooling air to the composite member that is forced through nozzle 820 and into the glass ribbon. Optionally, composite member 800 may include multiple nozzles that may be individually configured to pass or block air using corresponding valves (not shown). As shown, radiant air inlet 830 allows input radiative cooling air to travel through composite member 800 and exit outlet 840 at a higher temperature to extract heat from composite member 800 that was absorbed due to its proximity to the hotter glass ribbon. Optionally, as discussed above, coolants other than air may be used to provide radiative cooling.

[0046] For example, radiative cooling can use specialized cooling media, including but not limited to gaseous helium, to improve cooling effectiveness and efficiency. The thermal conductivity of air is 0.0257 W / (mK), while that of helium is 0.1513 W / (mK). Equivalent materials are cottonseed oil at 0.173 W / (mK) and water at 0.588 W / (mK). When gaseous helium is used, a system fan can be used and cooling will be much more efficient than using air without the problems associated with cooling with oil or water. The cooling system can be a closed loop via a radiant air box with a backup vessel that stores helium. Optionally, the cooling medium can be a mixture of air and helium that is less than 100% pure gaseous helium.

[0047] Any number of radiating members 700 and composite members 800 can be provided and used to cool the thicker portions of the glass ribbon at a different rate than the thinner portions. Any of the members 700, 800 can be maintained at a lower temperature than the remainder of the CCA in which it is located and can be located a shorter distance from the surface of the thicker portions of the glass ribbon. Optionally, the glass ribbon can be cooled from the top, bottom, or both sides.

[0048] In another embodiment, the air box can provide heating in addition to cooling. The heating function can be used to reduce temperature gradients that occur at the interface between the thick and thin sections of the glass ribbon. In one configuration shown in FIG. 9, two strip heaters 920 can be positioned to extend along two sides of the array of air nozzles 910 on the air box 900. The strip heaters 920 radiate heat into the glass ribbon to retain heat or reheat the exact location where the thick and thin interface exists to reduce stress in the glass ribbon at this interface.

[0049] The heaters may include section heating zones to heat the thin and / or thick sections at different rates. The section heaters may be used in combination with moving air boxes to provide precisely controlled heat treatment of the glass ribbon. Alternatively, the CCA modules may be maintained at a higher temperature than the temperature of the thin sections of the ribbon to heat such sections while localized cooling boxes cool the thick sections.

[0050] Any type of cooling (conventional, radiant, and combination), heating, or heating / cooling air boxes can be provided, each independently moved and positioned to align with any portion of the glass ribbon. The air boxes can be positioned together in the center of the glass ribbon to cover wider, thicker portions, or spaced apart toward the ends of the glass ribbon to cover narrower end strip configurations. The air boxes can be independently positioned above, below, to the side, or out of the way when not in use relative to the glass ribbon, and can be positioned in place manually or by an automated electromechanical positioning system. Optionally, any number of positions of any number of heating and / or cooling air boxes can be positioned by automation and preprogrammed to allow for different configurations of the process of the glass ribbon to be repeated.

[0051] 10A and 10B are models showing the effect of air flow from an air box pushing air onto the top surface of the glass ribbon. A portion of the glass ribbon, including thick and thin sections, is shown within the air volume surrounding that portion of the ribbon. Although not shown, the air box would be located immediately above and in close proximity to the thick section. The model in FIG. 10A shows that the cooler forced air cools the thick section of the glass ribbon. FIG. 10B shows that the increased air flow cools the thick section even more.

[0052] 11A and 11B are diagrams illustrating the cooling effect on the thick section of the glass ribbon as the distance from the air box to the glass ribbon changes. A comparison of the left and right sides of FIG. 11A shows that as the distance from the air box to the thick section increases, the cooling effect becomes wider or more distributed as the forced air spreads out from the air box.

[0053] FIG. 11B shows the control logic for aligning the air-cooled cold and hot zones. Corning's temperature monitoring system can measure and analyze the location of the hot zones (zones with slow heat flux on the ribbon, especially on thick strips, usually) and cold zones (close to the cooling effect of the airbox). The distance between the center of the hot zone and the center of the cold zone is calculated using a method developed by Corning, and the result is used to automatically adjust the gap to minimize the hot zone. The blue rectangular zone is the air-cooled zone, which can be calculated and predicted by the air-cooled control. The red irregular zone is the nature of the temperature distribution measured by thermal camera or other measurement tool. The control system calculates the center of the cold zone and the centerline of the hot zone, and minimizes the distance between the two accordingly.

[0054] 12-16 are cross-sectional views of CCA tunnels with different configurations and locations of air boxes. The red boxes shown in FIGS. 12-16 represent the location of any type of air box that may be used for heating and / or cooling, as discussed above. A representation of the glass ribbon configuration associated with the CCA tunnel configuration is shown around the CCA tunnel, where dark blue indicates thicker portions and light blue indicates thinner portions, similar to that shown in FIGS. 1A-1C. For the sake of brevity, descriptions of similar features will not be repeated.

[0055] 12A and 12B are cross-sectional views of a CCA tunnel 1200 showing a roller 1210 configured to support a glass ribbon moving on the roller 1210. In FIG. 12A, two air boxes 1020 are adjacent to each other on the roller 1210 and are arranged to cool the center of the glass ribbon. A representation of the glass ribbon is provided above the CCA tunnel, similar to the configuration shown in FIG. 1B. In FIG. 12B, two cooling boxes 1220 are arranged apart from each other on the roller 1210 and are arranged to cool two outer portions of the glass ribbon. A representation of the glass ribbon is provided above the CCA tunnel, similar to the configuration shown in FIG. 1C.

[0056] 13A and 13B are cross-sectional views of a CCA tunnel showing that an airbox can be positioned below the glass ribbon and controlled from the bottom of the CCA tunnel. Figure 13A includes an additional view showing that the airbox can be configured as described with respect to Figure 8.

[0057] Figure 14 shows an air box in a CCA tunnel that is vertically adjustable. It is possible to fill the entire width of a CCA tunnel with air boxes that are rigidly fixed across the machine width but can be raised and lowered. In such a configuration, the operator can decide which boxes to blow air into and raise them to the appropriate distance from the glass ribbon to properly focus the heating and / or cooling. Air boxes that are not needed can be left in a lower position and turned off.

[0058] FIG. 15 shows a CCA tunnel with air boxes positioned above and below the glass ribbon. Also shown in FIG. 15 is an additional local heater 1510. FIG. 16 shows a CCA tunnel with air boxes positioned both above and below the glass ribbon, and also an additional local heater 1610 similar to that shown in FIG. 15. However, heater 1610 differs in that it includes section heaters 1620, represented by different colored coils, and each section heater 1620 is individually controlled to heat thin and / or thick sections of the glass ribbon at different rates. Although five section heaters are shown, any number is possible. Section heaters 1620 can be used in combination with movable air boxes to provide precisely controlled heat treatment of the glass ribbon.

[0059] It should be understood that the foregoing description is only illustrative of the present invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the present invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variations that fall within the scope of the appended claims.

[0060] Preferred embodiments of the present invention will be described below in detail.

[0061] EMBODIMENT 1 1. A glass ribbon processing apparatus for producing a glass ribbon having a variable thickness, comprising: a first device for cooling a first portion of a width of the glass ribbon at a different rate than a second portion of a width of the glass ribbon, the first portion being thicker than the second portion; The device comprises:

[0062] EMBODIMENT 2 2. The apparatus of embodiment 1, wherein the first device is positioned above or below the glass ribbon and proximate to the glass ribbon.

[0063] EMBODIMENT 3 3. The apparatus of embodiment 1 or 2, wherein the first device is a heat exchanger that extracts heat from the first portion.

[0064] EMBODIMENT 4 3. The apparatus of embodiment 1 or 2, wherein the first device pushes air into the first portion.

[0065] EMBODIMENT 5 3. The apparatus of embodiment 1 or 2, wherein the first device is configured to extract heat from the first portion and push air into the first portion.

[0066] EMBODIMENT 6 6. An apparatus as described in any one of embodiments 3 to 5, wherein the first device is provided with a valve that regulates the air pushed into the first portion.

[0067] EMBODIMENT 7 7. An apparatus as described in any one of the preceding embodiments, wherein the first device comprises a heater.

[0068] EMBODIMENT 8 8. The apparatus of any one of the preceding claims, further comprising a second device for heating any portion of the width of the glass ribbon.

[0069] EMBODIMENT 9 9. The apparatus of embodiment 8, wherein the second device heats the interface between the first portion and the second portion.

[0070] EMBODIMENT 10 8. The apparatus of any one of embodiments 1 to 7, wherein the first device is a plurality of first devices configured to be aligned within the apparatus.

[0071] EMBODIMENT 11 11. The apparatus of any of the previous claims, further comprising a section heater including at least two heating zones to apply a heat treatment to the glass ribbon.

[0072] EMBODIMENT 12 1. A method for producing a glass ribbon of varying thickness, comprising the steps of: conveying the glass ribbon; cooling a first portion of the width of the glass ribbon at a different rate than a second portion of the width of the glass ribbon, the first portion being thicker than the second portion; A method comprising:

[0073] EMBODIMENT 13 13. The method of claim 12, wherein the cooling is applied by a device positioned above or below the glass ribbon and proximate to the glass ribbon.

[0074] EMBODIMENT 14 13. The method of embodiment 12, wherein the cooling is provided by a heat exchanger that extracts heat from the first portion.

[0075] EMBODIMENT 15 13. The method of embodiment 12, wherein the cooling is by air being forced into the first portion.

[0076] EMBODIMENT 16 14. The method of embodiment 13, wherein the first device is configured to extract heat from the first portion and push air into the first portion.

[0077] EMBODIMENT 17 17. The method of claim 13 or 16, wherein the first device heats the glass ribbon.

[0078] EMBODIMENT 18 13. The method of embodiment 12, further comprising heating the interface between the first portion and the second portion.

[0079] EMBODIMENT 19 13. The method of embodiment 12, further comprising heating the width of the glass ribbon in sections. [Explanation of symbols]

[0080] 500 Airbox 510 Lola 700 Radiating member 710 Entrance 720 Exit 800 Composite Materials 810 Conventional air inlet 820 Nozzle 830 Radiant air inlet 840 Exit 900 Airbox 910 Air Nozzle Array 920 Strip Heater 1200 CCA Tunnel 1210 Lola 1220 Cooling Box 1510,1610 Local heater 1620 Section heater

Claims

1. 1. A glass ribbon processing apparatus for producing a glass ribbon having a variable thickness, comprising: a first device for cooling a first portion of a width of the glass ribbon at a different rate than a second portion of a width of the glass ribbon, the first portion being thicker than the second portion; The device comprises:

2. The apparatus of claim 1 , wherein the first device is positioned above or below the glass ribbon and proximate to the glass ribbon.

3. The apparatus of claim 1 , wherein the first device is a heat exchanger that extracts heat from the first portion.

4. The apparatus of claim 1 , wherein the first device pushes air into the first portion.

5. The apparatus of claim 1 , wherein the first device is configured to extract heat from the first portion and push air into the first portion.

6. The apparatus of claim 3 , wherein the first device comprises a valve that regulates the air pushed into the first portion.

7. The apparatus of claim 1 , wherein the first device comprises a heater.

8. The apparatus of claim 1 , further comprising a second device for heating any portion of a width of the glass ribbon.

9. The apparatus of claim 8 , wherein the second device heats an interface between the first portion and the second portion.

10. The apparatus of claim 1 , wherein the first device is a plurality of first devices configured to be aligned within the apparatus.

11. The apparatus of claim 1 , further comprising a section heater including at least two heating zones for subjecting the glass ribbon to a heat treatment.

12. 1. A method for producing a glass ribbon of varying thickness, comprising the steps of: conveying the glass ribbon; cooling a first portion of the width of the glass ribbon at a different rate than a second portion of the width of the glass ribbon, the first portion being thicker than the second portion; A method comprising:

13. The method of claim 12 , wherein the cooling is applied by a device located above or below the glass ribbon and proximate to the glass ribbon.

14. The method of claim 12 , wherein the cooling is provided by a heat exchanger that extracts heat from the first portion.

15. The method of claim 12 , wherein the cooling is by air being forced into the first portion.

Images