Apparatus and process for determining distance between glass substrate and coater

Abstract

To provide a combination of apparatuses for determining the distance between a glass substrate and a coater and a process thereof.SOLUTION: Provided is a combination of a chemical vapor deposition (CVD) coater and at least one capacitive proximity sensor, comprising: a CVD coater; and at least one capacitive proximity sensor attached to the CVD coater, wherein the at least one capacitive proximity sensor is arranged to determine the distance between a glass substrate and the CVD coater.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an apparatus and a process for determining the distance between a glass substrate and a coater. More specifically, the present invention relates to the coating of a glass substrate by chemical vapor deposition (CVD), and in particular to the sensing of the position of the coater relative to the position of the glass substrate on which the coating is to be formed.

Background Art

[0002] To ensure the reproducibility of the coating, it is desirable to provide a rapid and repeatable way to set the height of the coater. Further, an approach that prevents the coater from dropping onto a glass substrate, such as a glass ribbon in a float glass manufacturing process, causing breakage of the substrate and damage to the coater would be advantageous. Such an approach could also beneficially provide a warning signal to alert the operator of the proximity of the coater to the glass substrate.

[0003] Known approaches for determining the spacing between a glass ribbon and a coater are described in U.S. Patent No. 5,298,073, which relates to the use of differential pressure. A position sensor is attached to the coater at a selected position. The sensor includes an annular outlet from which a compliant gas is discharged at a position close to the glass surface, and a central opening for measuring the back pressure resulting from the impingement of the gas on the glass surface. The back pressure is a function of the distance from the glass surface to the annular outlet and is smoothly and clearly defined as a pressure-versus-distance for the range of distances over which the coater is intended to operate, by the size of the annular passage and the gas flow rate through it. ​​​​​​​​​​​​​​A curve is generated. By comparing the observed pressure with the pressure at a known distance, the distance from the sensor to the glass, i.e., from the coater to the glass, is indicated. Up to the glass from the sensor, that is, the distance from the coater to the glass is shown.

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] However, there are drawbacks associated with the differential pressure approach. For example, this technique requires a complex configuration of pipes, and problems related to calibration and sensitivity to changes in gas pressure may occur. A complex configuration of the pipe is required, and problems related to calibration and sensitivity to changes in gas pressure may occur. There is a possibility of occurring.

[0005] Therefore, it would be advantageous to provide an approach that at least reduces and preferably solves the aforementioned problems. It would be advantageous.

MEANS FOR SOLVING THE PROBLEM

[0006] According to a first aspect of the present invention, there is provided a combination of a chemical vapor deposition (CVD) coater and at least one capacitive proximity sensor, comprising: the CVD coater, at least one capacitive proximity sensor attached to the CVD coater, wherein the at least one capacitive proximity sensor is configured to determine the distance between the glass substrate and the CVD coater. A combination is provided. The combination is configured to determine the distance between the glass substrate and the CVD coater.

EFFECTS OF THE INVENTION

[0007] Surprisingly, it has been found that the combination of the first aspect provides a convenient and accurate way to determine the distance between the glass substrate and the CVD coater. This combination enables real-time monitoring of the coater height without the characteristic drawbacks of known approaches. The distance between the glass substrate and the CVD coater is determined. This combination enables real-time monitoring of the coater height without the characteristic drawbacks of known approaches. It enables real-time monitoring of the coater height without the characteristic drawbacks of known approaches. To do.

[0008] In the following discussion of the present invention, unless stated to the contrary, disclosure of an alternative value for an upper or lower limit of a parameter range, in conjunction with the suggestion that one of the above values is much more preferred than the other, implies that each intermediate value of the parameter is, in itself, also more preferred than the less preferred of the above values, and for each value between the less preferred value and the intermediate value. This should be construed as an implicit statement. should be construed as an implicit statement that it is more preferred.

[0009] Throughout this specification, the terms "comprising" or "comprises" mean including the specified component but not excluding the presence of other components. The term "consisting essentially of" means including the specified component but excluding materials present as impurities, inevitable materials resulting from the process used to provide the above components, and other components added for purposes other than achieving the technical effects of the present invention. Typically, when referring to a composition, a composition consisting essentially of a set of components contains less than 5% by weight, typically less than 3% by weight, and more typically less than 1% by weight of unspecified components.

[0010] The term "consisting of" means including the specified component and excluding other components.

[0011] If necessary, depending on the context, the use of the terms "comprising" or "comprises" may be interpreted to include the meaning of "consisting essentially of" or "consists essentially of", or may also be interpreted to include the meaning of "consisting of" or "consisting of". References in this specification such as "in the range of x to y" include the interpretation of "from x to y", and thus are intended to include the values x and y.

[0012]

Best Mode for Carrying Out the Invention

[0013] Preferably, the capacitive proximity sensor includes a sensor unit and a control unit. Preferably, the above sensor unit and control unit are configured to be electrically coupled to each other during use. The above sensor unit and control unit may be electrically coupled to each other by a cable or other suitable means during use. Preferably, the capacitive proximity sensor includes a sensor unit, a control unit, and a cable. Preferably, the cable is insulated, and more preferably, is insulated by one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the temperature of the cable may be adjusted during use by enclosing at least a portion, preferably all, of the cable within a conduit including cooling means. Preferably, the above cooling means includes water or oil. Preferably, the above water or oil is recycled.​​​​ It is. Preferably, the sensor unit and the cable are operable at a temperature of at least 650 ° C, more preferably at least 700 ° C, even more preferably at least 750 ° C, and most preferably at least 800 ° C.

[0014] Preferably, the capacitive proximity sensor is configured to determine the distance between the surface of the glass substrate and the surface of the CVD coater. The above surface of the glass substrate is such that the capacitive proximity sen sor is configured to determine the distance between the coating surface and the surface of the CVD coater, and may be coated. Preferably, the above surface of the glass substrate is the surface closest to the CVD coater. Preferably, the above surface of the CVD coater is the surface closest to the glass substrate. Preferably, the CVD coater is configured to move to change the distance between the surface of the glass substrate and the surface of the CVD coater. In use, preferably, the glass substrate is stationary in the plane or moves in the plane, and the CVD coater is configured to move to change the distance between the above plane and the surface of the CVD coater. Preferably the CVD coater is configured to move substantially perpendicular to the above plane to change the distance between the above plane and the surface of the CVD coater.

[0015] Preferably, the above sensor unit includes a sensor electrode. Preferably, the above sensor electrode includes one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. The above sensor electrode is cylindrical or cuboid shape. Preferably, the CVD coater is configured to change the distance between the above plane and the surface of the CVD coater and is configured to move substantially perpendicular to the above plane.

[0016] Preferably, the above sensor unit includes a sensor electrode. Preferably, the above sensor electrode includes one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. The above sensor electrode is cylindrical or cuboid It may be of any suitable shape such as etc. Preferably, the end of the sensor electrode faces the glass substrate during use. during use.

[0017] Preferably, the sensor electrode is at least partially surrounded by one or more electrical insulating materials such as ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the sensor electrode is at least partially surrounded by an electrically insulated air gap. Preferably, the electrical insulating material is at least partially surrounded by a guard ring. Preferably, the guard ring contains one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. during use. Preferably, the sensor electrode is at least partially surrounded by one or more electrical insulating materials such as ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the sensor electrode is at least partially surrounded by an electrically insulated air gap. Preferably, the electrical insulating material is at least partially surrounded by a guard ring. Preferably, the guard ring contains one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. during use. Preferably, the electrical insulating material is at least partially surrounded by a guard ring. Preferably, the guard ring contains one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. Preferably, the guard ring contains one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. Preferably, the guard ring contains one or more of copper, graphite, titanium, brass, silver, platinum, palladium, steel, and mixed metal oxides. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. Preferably, the guard ring is at least partially surrounded by an electrical insulating material such as one or more of ceramic, silicone rubber, glass fiber, mica, and magnesium oxide. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap. Alternatively or additionally, the guard ring is at least partially surrounded by an electrically insulated air gap.

[0018] Preferably, the combination includes two or more capacitive proximity sensors attached to the CVD coater, more preferably three or more capacitive proximity sensors attached to the CVD coater, and even more preferably four or more. A greater number of sensors means that in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is arranged on a non-parallel plane), even if a certain sensor indicates that it is away from the glass substrate, the CVD coater is in contact with the glass substrate. Preferably, the combination includes two or more capacitive proximity sensors attached to the CVD coater, more preferably three or more capacitive proximity sensors attached to the CVD coater, and even more preferably four or more. A greater number of sensors means that in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is arranged on a non-parallel plane), even if a certain sensor indicates that it is away from the glass substrate, the CVD coater is in contact with the glass substrate. Preferably, the combination includes two or more capacitive proximity sensors attached to the CVD coater, more preferably three or more capacitive proximity sensors attached to the CVD coater, and even more preferably four or more. A greater number of sensors means that in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is arranged on a non-parallel plane), even if a certain sensor indicates that it is away from the glass substrate, the CVD coater is in contact with the glass substrate. Preferably, the combination includes two or more capacitive proximity sensors attached to the CVD coater, more preferably three or more capacitive proximity sensors attached to the CVD coater, and even more preferably four or more. A greater number of sensors means that in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is arranged on a non-parallel plane), even if a certain sensor indicates that it is away from the glass substrate, the CVD coater is in contact with the glass substrate. Preferably, the combination includes two or more capacitive proximity sensors attached to the CVD coater, more preferably three or more capacitive proximity sensors attached to the CVD coater, and even more preferably four or more. A greater number of sensors means that in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is arranged on a non-parallel plane), even if a certain sensor indicates that it is away from the glass substrate, the CVD coater is in contact with the glass substrate. Preferably, the combination includes two or more capacitive proximity sensors attached to the CVD coater, more preferably three or more capacitive proximity sensors attached to the CVD coater, and even more preferably four or more. A greater number of sensors means that in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is arranged on a non-parallel plane), even if a certain sensor indicates that it is away from the glass substrate, the CVD coater is in contact with the glass substrate. This becomes possible, which is advantageous for the situation. Preferably, each capacitive proximity sensor's sensor unit is located in the area around the CVD coater. Preferably each capacitive proximity sensor's sensor unit is positioned such that the end of the sensor unit is substantially horizontal or preferably horizontal with the lower surface of the CVD coater. Preferably the lower surface of the CVD coater is the surface closest to the glass substrate. Preferably, each capacitive proximity sensor's sensor unit is positioned such that the end of the sensor electrode is substantially horizontal or preferably horizontal with the lower surface of the CVD coater. Preferably, each capacitive proximity sensor is located in the area around the CVD coater. Preferably each capacitive proximity sensor is located in the area of the corner of the lower surface of the CVD coater.

[0019] Preferably, the CVD coater is substantially a rectangular parallelepiped. Preferably, the CVD coater includes two side surfaces, one front surface, one back surface, one upper surface, and one lower surface. Preferably, the two side surfaces are on opposite sides of each other, and the front and back surfaces on opposite sides of each other are connected and perpendicular to them. Preferably, the upper and lower surfaces are on opposite sides of each other and both are connected to the above-mentioned side surfaces, front surface, and back surface. Preferably, one or more gas distribution passages extend vertically between the side surfaces across the above-mentioned lower surface. When the glass substrate is moving during use, the moving direction is from the front surface to the back surface of the CVD coater, that is, parallel to the side surface. Preferably, each capacitive proximity sensor, preferably each capacitive proximity sensor's sensor unit is such that the end of the sensor electrode is of the CVD coater It is attached to the front or back of the CVD coater so as to be substantially at the same height, preferably the same height as below. Alternatively or additionally, preferably, each capacitive proximity sensor - preferably the sensor unit of each capacitive proximity sensor, is attached to the front or back of the CVD coater, adjacent to the location where the surface contacts the side surface.

[0020] Preferably, the temperature of at least part of the coater is adjusted, more preferably by using cooling means to be adjusted. Preferably, the cooling means includes water or oil, preferably oil is included. Preferably, the coater includes one or more gas distribution passages. Preferably, one or more gas distribution passages can be used to release a gaseous mixture. Preferably, the above one or more gas distribution passages include one or more inner walls defining the passages. Preferably, the above one or more gas distribution passages extend horizontally across the glass substrate in use. Preferably the one or more gas distribution passages have a slot-like shape. Preferably, the one or more gas distribution passages are configured to release a curtain of the gaseous mixture. Preferably the temperature of the inner wall of the gas distribution passage is adjusted using cooling means. Preferably, the cooling means includes oil.

[0021] Preferably, the sensor unit is at least partially surrounded by a housing . Preferably, a part of the CVD coater constitutes a part of the housing, for example, the outer wall of the above coater may constitute the wall of the housing. Preferably, the temperature of the above part of the CVD coater constituting a part of the housing is adjusted as described in the previous paragraph. Preferably ... Alternatively, the temperature of the sensor unit is adjusted by the above part of the coter that forms part of the housing. This enables control to prevent the temperature of the sensor unit from becoming too high (e.g., > 750 °C). This is because such high temperatures can adversely affect the performance of the sensor.

[0022] Preferably, the sensor electrode includes at least one exposed portion that is not enclosed by the housing or any part of the sensor unit. The sensor unit is preferably configured such that the at least one exposed portion of the sensor electrode faces the glass substrate in use. Preferably, the at least one exposed portion of the sensor electrode that faces the glass substrate in use is the end of the sensor electrode. The at least one exposed portion of the sensor electrode preferably has a flat surface.

[0023] Preferably, at least a part of the sensor unit is protected from the surrounding atmosphere by an anti-fouling coating and / or an anti-fouling sheet. Such a configuration prevents the sensor from being contaminated by coating materials or fragments of the float bath atmosphere that can affect the accurate measurement ability of the sensor. This approach also protects the sensor during the cleaning and maintenance operations of the coter.

[0024] Preferably, the sensor unit includes a sensor electrode, and preferably, at least a part of the sensor electrode is protected from the surrounding atmosphere by an anti-fouling coating and / or an anti-fouling sheet. Preferably, at least one exposed portion of the sensor electrode is an anti-fouling co ating. ​​​​​​​​​​​-ting and / or protected from the ambient atmosphere by an antifouling sheet. Preferably any portion of the sensor electrode that would otherwise be exposed to the ambient atmosphere is protected from the ambient atmosphere by an antifouling coating and / or an antifouling sheet. Preferably any portion of the sensor unit that would otherwise be exposed to the ambient atmosphere is protected from the ambient atmosphere by an antifouling coating and / or an antifouling sheet.

[0025] Preferably, the antifouling coating contains a non-conductive material. Preferably, the antifouling coati ng contains one or more of bicarbonates such as sodium bicarbonate and calcium bicarbonate, sulfates such as sodium sulfate and calcium sulfate, nitrides such as boron nitride and aluminum nitride, low boiling point hydrogen-treated naphtha, silazanes such as polysilazane, alkali silicates, silica, and / or one or more of organic silica. Preferably, the antifouling coating is removable Any contaminants that have adhered to the coating during use can be removed by a removable coating. Preferably, the antifouling coating can be removed using a solvent such as an organic solvent Preferably, the organic solvent is an alcohol such as isopropyl alcohol or eth anol.

[0026] Preferably, the antifouling sheet contains one or more of alumina, quartz, zirconia, and / or non-conductive cera mic. Preferably, the antifouling sheet is disk-shaped. Preferably the housing or the sensor unit includes a holder suitable for holding the antifouling sheet Preferably, the holder is configured to receive the antifouling sheet ​It includes slots. Preferably, the antifouling sheet is held by the holder. This configuration allows the antifouling sheet to be conveniently attached to the housing or sensor unit before using, cleaning or maintaining the coater, and then both the contaminants adhering to the sheet and the sheet can be easily removed, which is beneficial.

[0027] Preferably, the antifouling sheet has a thickness of at least 0.01 mm, more preferably at least 0. 1 mm, even more preferably at least 0.3 mm, and most preferably at least 0.4 mm, but preferably at most 3 mm, more preferably at most 1 mm, even more preferably at most 0.7 mm, and most preferably at most 0.6 mm. These preferred thicknesses are beneficial in that they provide sufficient protection without adversely affecting the performance of the sensor.

[0028] Preferably, the sensor unit is configured to detect the distance between a glass substrate, which may be coated, and a CVD coater. Particularly preferably, the sensor electrodes are configured to detect the distance between the glass substrate and the CVD coater. Preferably, the sensor unit is configured to transmit a signal to a control unit, and the signal indicates the distance between the glass substrate and the CVD coater. Preferably, the sensor unit is configured to transmit the signal to the control unit by means of a cable or other suitable means during use. Preferably, the control unit is configured to indicate the distance between the glass substrate and the CVD coater. Preferably, the control unit is configured to provide means for an operator to control the distance between the glass substrate and the CVD coater. For example, the control unit ​ It can also be configured to automatically maintain a constant distance between the glass substrate and the CVD coater. With this configuration, the operator can easily adjust the position of the glass substrate relative to the CVD coater. To account for any variation in position, the distance between the glass substrate and the CVD coater was The change in the position of the glass substrate is not required to be continuously monitored by the glass substrate. This can occur for a variety of reasons, including problems with the equipment transporting the plate, or the glass substrate. Where the sheet is a molten glass ribbon produced as part of the float glass process, Waves in the underlying tin bath can cause such fluctuations. Such variations can cause inconsistencies in coating thickness and quality. Being able to disable them is important.

[0029] Preferably, the control unit is configured to determine whether the CVD coater is closer to the glass substrate than a predetermined minimum distance. Such warnings may be audible and / or visual. Such events may occur in CVD coaters, glass substrates, and This can damage equipment or materials underneath the glass substrate, such as a tin bath. Such a warning is useful to avoid the CVD coater coming into contact with the glass substrate. do.

[0030] Preferably, the above-mentioned CVD coater and at least one capacitive proximity sensor The combination is suitable for use in the manufacturing process of float glass. The combination includes the float bath section, the annealing furnace, and / or the annealing furnace. It may be suitable for use as part of a float glass facility, such as a lehr gap. Preferably or, the glass substrate is formed using a well-known float glass manufacturing process There is. In this embodiment, the glass substrate may also be referred to as a glass ribbon. Preferably, the combination of the first aspect is utilized during the manufacturing process of float glass . However, it should be understood that this combination can be fully utilized separately from the float glass manufacturing process or even after the formation and cutting of the glass ribbon.

[0031] According to a second aspect of the present invention, a capacitive proximity sensor for attachment to a CVD coater Comprising A sensor unit, A control unit, and The capacitive proximity sensor is configured to determine the distance between the glass substrate and the CVD coater And At least a part of the sensor unit is protected from the surrounding atmosphere by an anti-fouling coating and / or an anti-fouling sheet A capacitive proximity sensor is provided.

[0032] Surprisingly, it has been found that the sensor according to the second aspect is particularly suitable for determining the distance between the glass substrate and the CVD coater. The sensor can operate reliably in a CVD coating environment without being contaminated by coating materials or debris in the float bath atmosphere that may affect the accurate measurement ability of the sensor. Also, the sensor is protected during the cleaning and maintenance operations of the coater.

[0033] Preferably, the capacitive proximity sensor is suitable for use during the manufacturing process of float glass is being performed.

[0034] According to a third aspect of the present invention, a process for determining the distance between a glass substrate and a CVD coater, comprises: i) providing a combination of a glass substrate, and a CVD coater and a capacitance proximity sensor according to the first aspect of the present invention; ii) using the capacitance proximity sensor to determine the distance between the glass substrate and the CVD coater. This process provides a convenient and accurate method for determining the distance between a glass substrate and a CVD coater, and enables real-time monitoring of the coater height without the characteristic drawbacks of known approaches. The process is preferably carried out when the glass substrate is at a temperature in the range of 350 °C to 800 °C, more preferably when the glass substrate is at a temperature in the range of 550 °C to 770 °C. Carrying out the process when the glass substrate is at these preferred temperatures means that the glass substrate is conductive, and thus the capacitance is measured between the sensor and the glass substrate. This configuration makes it possible to determine the distance more easily compared to the case where the glass substrate, which would require a stationary reference target, is non-conductive.

[0035] The process can be carried out in conjunction with the manufacture of the glass substrate. For example, the glass substrate can be formed using a float glass manufacturing process. Advantageously, this process can be carried out in the float bath section, in the annealing furnace, and / or in the lehr section of the float glass manufacturing process. is possible.

[0036] The process may be carried out when the glass substrate is at a temperature in the range of 350 °C to 800 °C, more preferably when the glass substrate is at a temperature in the range of 550 °C to 770 °C. Carrying out the process when the glass substrate is at these preferred temperatures means that the glass substrate is conductive, and thus the capacitance is measured between the sensor and the glass substrate. This configuration makes it possible to determine the distance more easily compared to the case where the glass substrate, which would require a stationary reference target, is non-conductive. in the lehr section of the float glass manufacturing process. The process can be carried out in conjunction with the manufacture of the glass substrate. For example, the glass substrate can be formed using a float glass manufacturing process. Advantageously, this process can be carried out in the float bath section, in the annealing furnace, and / or means that the glass substrate is conductive, and thus the capacitance is measured between the sensor and the glass substrate. This configuration makes it possible to determine the distance more easily compared to the case where the glass substrate, which would require a stationary reference target, is non-conductive. This process provides a convenient and accurate method for determining the distance between a glass substrate and a CVD coater, and enables real-time monitoring of the coater height without the characteristic drawbacks of known approaches. This process provides a convenient and accurate method for determining the distance between a glass substrate and a CVD coater, and enables real-time monitoring of the coater height without the characteristic drawbacks of known approaches. becomes possible.

[0037] The process can be carried out in conjunction with the manufacture of the glass substrate. For example, the glass substrate can be formed using a float glass manufacturing process. Advantageously, this process can be carried out in the float bath section, in the annealing furnace, and / or in the lehr section of the float glass manufacturing process. in the lehr section of the float glass manufacturing process. It can be carried out in a float glass facility, such as in a rare gap. The above ra re gap is defined as the area between the float bath and the annealing furnace. In the above rare ga p, the surrounding atmosphere can change from the reducing atmosphere of the float bath to the oxidizing (air ambient) atmosphere inside the annealing furnace.

[0038] Preferably, the CVD coater extends horizontally across the glass substrate and is preferably provided at a distance thereabove. In certain embodiments, the gaseous mixture is supplied through the CVD coater and, during the process, can be discharged from the CVD coater using one or more gas distribution passages (sometimes referred to as beams). Preferably, each gaseous mixture is formed before being supplied through the CVD coater. For example, the precursor compounds can be mixed in a supply line connected to the inlet of the CVD coater. In other embodiments, one or more gaseous mixtures can be formed inside the CVD coater. Preferably, the above one or more gas distribution passages include one or more inner walls defining the passages. Preferably, the above one or more gas distribution passages extend horizontally across the glass substrate. Preferably, the above one or more gas distribution passages have a slot-like shape. Preferably, the above one or more gas distribution pa ssages are configured to discharge a curtain of the gas mixture. Preferably, the CVD coater is configured to move to vary the distance between the surface of the glass substrate and the surface of the CVD coater. In use, preferably, the glass substrate is stationary in the plane or moves in the plane, and the CVD coater is above the above plane and moves.

[0039] Preferably, the CVD coater is configured to move to vary the distance between the surface of the glass substrate and the surface of the CVD coater. In use, preferably, the glass substrate is stationary in the plane or moves in the plane, and the CVD coater is above the above plane and moves. It is configured to move in order to vary the distance between the surface and the surface of the CVD coater. Preferably, the CVD coater is configured to move substantially perpendicular to the plane in order to vary the distance between the plane and the surface of the CVD coater.

[0040] Preferably, the glass substrate is moving during the process. Preferably, the glass substrate moves at a speed exceeding a predetermined speed, for example, 3 m / min, during the process. More preferably the glass substrate moves at a speed between 3 m / min and 20 m / min during the process.

[0041] Preferably, the process is carried out at substantially atmospheric pressure during the float glass manufacturing process. Alternatively, the process may be carried out using low pressure or ultra-high vacuum. The CVD coater may be an aerosol-assisted CVD coater or a direct liquid injection CVD coater. Further, the CVD coater may be a microwave plasma-assisted CVD coater, a plasma-enhanced CVD coater, a remote plasma-enhanced CVD coater, an atomic layer C VD coater, a combustion CVD coater (flame pyrolysis), a hot wire CVD coater, an organometallic CV D coater, a rapid thermal CVD coater, a photo-initiated CVD coater, or vapor phase e pitaxy may be used.

[0042] The glass substrate may be a transparent metal oxide-based glass ribbon or pane. The glass ribbon or pane may be a transparent or colored float glass ribbon or pane. A typical soda-lime silicate glass composition is (by weight), SiO2 69 - 74%; Al2O3 0 - 3%; Na2O 10 - 16%; K2O 0 - 5% ​​0-6% MgO; 5-14% CaO; 0-2% SO3; and Fe2O30 The glass composition may also contain other additives, such as .005 to 2%, usually in amounts up to 2%. Clear float glass may contain refining aids that may be present in The composition is as defined in BS EN 572-1 and BS EN 572-2 (2004). In clear float glass, the weight level of Fe2O3 is usually Float glass with an Fe2O3 content of less than about 0.05% by weight is usually This glass is usually called low iron float glass. It is usually made of the same base as the other oxides. With this composition, low iron float glass is similar to clear float glass in that it is made of soda lime. It is also a silicate glass. Tinted float glass usually contains at least 0.5% Fe by weight. 2O3, e.g., 1.0 wt. % Fe2O3. Alternatively, the glass ribbon or The glass ribbons or panes are borosilicate-based, alkali aluminosilicate-based Glass ribbons or panes of aluminum oxide or crystalline glass ribbons based on aluminum oxide It is either Pain or

[0043] According to a fourth aspect of the present invention, a method for determining the distance between a glass substrate and a CVD coater is provided. For this purpose, the use of a capacitive proximity sensor is provided.

[0044] According to a fifth aspect of the present invention, there is provided a capacitive proximity sensor attached to a CVD coater. The present invention provides the use of an anti-soiling coating and / or an anti-soiling sheet to protect the substrate.

[0045] Any of the features described above with respect to any aspect of the invention may also be used with respect to any other aspect of the invention. can be used with respect to the aspects. Any invention described in this specification, with the necessary modifications added, can be combined with any feature in any other invention described in this specification and. Any feature applicable to one aspect of the present invention can be used in any combination and in any number as will be understood. Furthermore, they can also be used in any combination and in any number together with any other aspect of the present invention . This includes, but is not limited to, dependent claims from claims used as dependent claims of other claims in the claims of this application .

[0046] The reader's attention is directed to all papers and documents that were filed simultaneously with or prior to this specification in connection with this application and that were made available for public inspection together with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[0047] All features disclosed in this specification (including the appended claims, abstract, and drawings), and / or all steps of any method or process disclosed, can be combined in any combination, except combinations in which at least some of such features and / or steps are mutually exclusive.

[0048] Each feature disclosed in this specification (including the appended claims, abstract, and drawings) can be replaced by an alternative feature that serves the same, equivalent, or similar purpose, unless specifically stated otherwise. Therefore, unless specifically stated otherwise, each disclosed feature is merely an example of a general series of equivalent or similar features.

Brief Description of the Drawings

[0049] Next, the present invention will be further described by the following specific embodiments, which are given by way of illustration and not limitation, with reference to the following accompanying drawings:

Figure 1

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Figure 4

Figure 5

[0050] As described above, the present invention can be used in conjunction with the production of glass substrates in the float glass process. The float glass process is typically carried out using a float glass facility (10) such as shown in FIG. 1. However, it should be understood that the float glass facility (10) described herein is merely an example of such a facility. As shown in FIG. 1, the float glass facility (10) may include a canal section (20) through which molten glass (19) is sent to a float bath section (11) where a glass substrate is formed from the molten furnace. In this embodiment, the glass substrate is referred to as a glass ribbon (8). However, it should be understood that the glass substrate is not limited to being a glass ribbon.

[0051] As shown in FIG. 1, the float glass facility (10) may include a canal section (20) through which molten glass (19) is sent to a float bath section (11) where a glass substrate is formed from the molten furnace. In this embodiment, the glass substrate is referred to as a glass ribbon (8). However, it should be understood that the glass substrate is not limited to being a glass ribbon. ​​​​​​​The glass ribbon (8) is fed from the bath section (11) to the adjacent annealing furnace ( The mixture passes through a float bath section (12), and a cooling section (13). 1) is made up of a bottom section (14) which contains a bath of molten tin (15), a roof (16), and a countersunk section (17). The roof (16), the side walls and the end wall (17) are connected to each other. The walls (17) are connected together to an encased chamber in which a non-oxidizing atmosphere is maintained to prevent oxidation of the molten tin (15). An enclosure (18) is defined.

[0052] During operation, molten glass (19) is forced through the cap under the regulating tweel (21). The tin flows downward in a controlled amount along the channel (20) onto the surface of the tin bath (15). On the molten tin surface, the molten glass (19) is subjected to the effects of gravity and surface tension as well as certain mechanical The glass ribbon (8) is then formed by spreading laterally under the influence of the magnetrons and proceeding across the tin bath (15). The glass ribbon (8) passes over the lift-out rolls (22) and enters the bath section. The strip is then removed from the roll (11) and annealed in an annealing furnace (12) and cooled on aligned rolls. The coating deposition is further carried out in the glass making line. Along the line, for example, the gap (2 8) or in an annealing furnace (12), but It is preferably carried out in the bath section (11).

[0053] As shown in FIG. 1, four CVD coaters (9), (9A), (9B), (9C) ) is shown in the float bath section (11). It may be like this. Also, the description of the CVD coater suitable for implementing the present invention is in US Patent Application Serial Number 61 / 466,501. In FIG. 1, the 16 capacitive proximity sensors respectively arranged in the corner regions of the lower surface of each CVD coater are not shown. One or more CVD coaters combined with the capacitive proximity sensors may be alternatively or additionally arranged in the rare gap (28). By-products are removed through the coater extraction slot and then through the anti-pollution plant. To prevent oxidation of the molten tin (15) including the float bath, a suitable non-oxidizing atmosphere, generally nitrogen, or a mixture of nitrogen and hydrogen with nitrogen being dominant, can be maintained within the float bath section

[0054] (11). Atmospheric gas is introduced through the conduit 23 operably coupled to the distribution manifold (24). The non-oxidizing gas is usually introduced at a rate sufficient to maintain a slight positive pressure on the order of about 0.001 to about 0.01 atmospheres higher than the ambient atmospheric pressure while compensating for normal losses. For the purpose of explaining the present invention, the above pressure range is regarded as constituting the normal atmospheric pressure. CVD is generally carried out essentially at atmospheric pressure. Therefore, the pressure within the float bath section (11), the annealing furnace (12), and / or the gap (28) between the float bath (11) and the annealing furnace (12) may be essentially at atmospheric pressure. The heat for maintaining the desired temperature regime within the float bath section (11) and the enclosure (18) is provided by the radiant heater (25) within the enclosure (18).

[0055] ​​​​​It can be achieved. The cooling section (13) is not enclosed, so the glass ribbon (8) is open to the surrounding atmosphere and thus the atmosphere in the furnace (12) is typically the atmosphere. Subsequently, the glass ribbon (8) is cooled to the ambient temperature. To cool the glass ribbon (8), the ambient air may be directed directly at the glass ribbon (8) by a fan (26) in the cooling section (13). To gradually reduce the temperature of the glass ribbon (8) according to a predetermined regime as the glass ribbon (8) is conveyed, a heater (not shown) may be provided in the annealing furnace (12). (8). (12). (12).

[0056] Figure 2 shows a bottom perspective view of a CVD coater (9) to which four capacitive proximity sensors (29) are attached according to the present invention. The CVD coater (9) is generally rectangular parallelepiped-shaped with side surfaces (30) connected to a front surface (not shown) and a back surface (31). The bottom surface (32) has a gas distribution passage (33) extending vertically between the two side surfaces (30) across the bottom surface. The glass substrate (34) is outlined below the CVD coater (9) adjacent to the bottom surface (32). In use, when the glass substrate (34) is moving (e.g., in a dynamic process such as a float glass manufacturing process), the moving direction is from the front surface of the CVD coater (9) to the back surface (31), i.e., parallel to the side surfaces (30). Two capacitive proximity sensors (29) are attached to each of the front surface and the back surface (3 (32) of the CVD coater (9) such that the ends of each sensor electrode (35) are at the same height as the bottom surface (32) of the CVD coater (9). The capacitive proximity sensors (29) are attached to the CVD coater (9) by sensor units (37) partially surrounded by a housing (32). (9). (9). (9) from the front surface to the back surface (31), i.e., parallel to the side surfaces (30). (29) are attached to each of the front surface and the back surface (3 (9) such that the ends of each sensor electrode (35) are at the same height as the bottom surface (32) of the CVD coater (9). The capacitive proximity sensors (29) are attached to the CVD coater (9) by sensor units (37) partially surrounded by a housing (37). is attached (associated cables and control units not shown). The capacitive proximity sensor (29) is attached to the front or back surface (31) of the CVD coater (9), adjacent to where the surface contacts the side surface (30). This frequency and position of the capacitive proximity sensor (29) enables the CVD coater (9) to contact the glass substrate (34) even when a sensor indicates that it is away from the glass substrate in situations where the glass substrate and / or the CVD coater is not horizontal (i.e., the glass substrate and / or the CVD coater is disposed on non-parallel planes), which is beneficial as it can counteract such situations.

[0057] FIG. 3 shows a perspective view of a capacitive proximity sensor (29) according to the present invention. The sensor (29) includes a sensor unit (37) partially surrounded by a housing connected to a control unit (38) via a cable (39). The control unit (38) has a touch screen (40) configured to display information regarding the proximity of the sensor unit (37) to the glass substrate (34). During use, the sensor electrodes (35) are configured to detect the distance between the glass substrate (34) and the CVD coater (9). The sensor unit (37) is configured to send a signal via the cable (39) to the control unit (38), and the signal indicates the distance between the glass substrate (34) and the CVD coater (9). In addition to controlling the operation of any connected sensor unit (37), the Alternatively, it can be connected to a separate control unit for controlling the CVD coater (9). By means of the control unit (38), the operator can control the distance between the glass substrate (34) and the CVD coater (9). For example, the control unit (38) is configured to automatically maintain a constant distance between the glass substrate (34) and the CVD coater (9) if desired. Further, the control unit (38) is configured to audibly and / or visually warn the operator when the CVD coater (9) is closer to the glass substrate (34) than a predetermined minimum distance, for example, about 2 to 30 mm, preferably about 2 to 10 mm.

[0058] The cable (39) is a three-axis cable of thin copper wire, thermally insulated by ceramic beads and continuously surrounded by a copper tube, glass fiber and a braided stainless steel mesh. The sensor unit (37) includes a cylindrical copper sensor electrode (35) continuously and partially surrounded by mica, a copper guard ring and a second layer of mica. The sensor unit (37) is housed in a stainless steel housing.

[0059] FIG. 4 shows a cross-sectional perspective view of the end of the sensor unit (37) of the capacitance proximity sensor (29) according to the present invention. The sensor unit (37) is partially surrounded by a rectangular parallelepiped-shaped housing. The contour shown at one end of the sensor unit (37) is the end of the cylindrical sensor electrode (35), and without the antifouling sheet (40) in the form of an alumina disk having a thickness of 0.5 mm and a circumference of 30 mm, it could be exposed to the surrounding atmosphere. This antifouling sheet (40) is configured to facilitate insertion and removal of the sheet (40) when the sheet (40) needs to be replaced. A holder (41), which is a square frame, having a slot (42) for removal is thus held in a predetermined position and the above exchange can be conveniently carried out during the execution of the CVD coating process.

Example

[0060] Test of the change over time of the sensor in the float bath section A capacitance proximity sensor according to FIG. 3 was attached to the CVD coater such that the sensor electrode was at the same height as the lower surface of the CVD coater. Then, the coater was tested in a float bath section set at a temperature of 755 °C. The CVD coater was lowered towards the surface of the float bath until the distance from the surface was 5 - 6 mm. Then, the variation in the reading provided by the capacitance proximity sensor was evaluated over several hours . The results are shown in Table 1 below.

Table 1

[0061] As can be seen from Table 1, there was no drift in the detected value over 6 hours. The only significant change occurred around 14:30, and there was a change in the height of the glass ribbon that was appropriately detected by the sensor. The slight variations detected at the remaining times are consistent with typical variations in the height of the ribbon surface.

[0062] Comparison between the capacitance proximity sensor and the micrometer in the presence of an alumina disk A capacitance proximity sensor according to FIG. 3 incorporating an alumina antifouling sheet according to FIG. 4 was attached to the CVD coater such that the sensor electrode was at the same height as the lower surface of the CVD coater. Attached. Using a micrometer, the lower surface of the coater was placed at a number of predetermined distances from the stainless steel plate. For each predetermined distance, the distance detected by the capacitance proximity sensor was recorded, and the results are shown in Table 2 and Figure 5 below.

Table 2

[0063] Table 2 and Figure 5 show that the presence of the alumina disk affected the distance indicated by the sensor. However, since this difference was predictable, the sensor could have been easily calibrated before use to obtain accurate values.

[0064] The present invention is not limited to the details of the foregoing embodiments. The present invention extends to any novel or any novel combination of the features disclosed in this specification (including the appended claims, abstract and drawings), or to any novel or any novel combination of the steps of any method or process disclosed. ​

Claims

1. A combination of a chemical vapor deposition (CVD) coater and at least one capacitive proximity sensor, comprising: a CVD coater; at least one capacitive proximity sensor attached to the CVD coater, wherein the at least one capacitive proximity sensor is configured to determine the distance between a glass substrate and the CVD coater.

2. The combination according to claim 1, wherein the capacitive proximity sensor includes a sensor unit, a control unit, and a cable, and the sensor unit and the control unit are configured to be electrically coupled to each other by the cable during use.

3. The combination according to claim 2, wherein the sensor unit and the cable are operable at a temperature of at least 650°C, more preferably at least 700°C, even more preferably at least 750°C, and most preferably at least 800°C.

4. The combination according to any one of claims 1 to 3, wherein the CVD coater is configured to move to change the distance between the surface of the glass substrate and the surface of the CVD coater.

5. The combination according to any one of claims 1 to 4, wherein the combination includes two or more capacitive proximity sensors attached to the CVD coater.

6. The combination according to any one of claims 2 to 5, wherein the sensor unit is at least partially surrounded by a housing, a part of the CVD coater constitutes a part of the housing, the temperature of the part of the coater constituting the part of the housing is adjusted using cooling means, and the temperature of the sensor unit is adjusted by the part of the coater constituting the part of the housing.

7. The combination according to any one of claims 2 to 6, wherein at least a part of the sensor unit is protected from the surrounding atmosphere by an anti-fouling coating and / or an anti-fouling sheet.

8. The combination according to claim 7, wherein any part of the sensor unit that would otherwise be exposed to the surrounding atmosphere is protected from the surrounding atmosphere by an anti-fouling coating and / or an anti-fouling sheet.

9. The anti-fouling coating is made of a non-conductive material, preferably sodium bicarbonate and bicarbonate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 。 ​ ​ ​ ​ ​ ​ Bicarbonates such as calcium, sulfates such as sodium sulfate and calcium sulfate, nitrides such as boron nitride and aluminum nitride, low-boiling hydrogen-treated naphtha, silazanes such as polysilazane, alkali silicates, silica, and / or one or more of organic silica A combination according to claim 7 or 8, comprising one or more of silazanes such as polysilazane, alkali silicates, silica, and / or organic silica A combination according to claim 7 or 8, comprising one or more of bicarbonates such as calcium, sulfates such as sodium sulfate and calcium sulfate, nitrides such as boron nitride and aluminum nitride, low-boiling hydrogen-treated naphtha, silazanes such as polysilazane, alkali silicates, silica, and / or organic silica A combination according to claim 7 or 8, comprising one or more of bicarbonates such as calcium, sulfates such as sodium sulfate and calcium sulfate, nitrides such as boron nitride and aluminum nitride, low-boiling hydrogen-treated naphtha, silazanes such as polysilazane, alkali silicates, silica, and / or organic silica

10. A combination according to any of claims 7 to 9, wherein the antifouling coating and / or the antifouling sheet is removable A combination according to any of claims 7 to 9, wherein the antifouling coating and / or the antifouling sheet is removable

11. A combination according to any of claims 7 to 10, wherein the antifouling sheet comprises one or more of alumina, quartz, zirconia, and / or non-conductive ceramic A combination according to any of claims 7 to 10, wherein the antifouling sheet comprises one or more of alumina, quartz, zirconia, and / or non-conductive ceramic

12. The housing or the sensor unit comprises a holder suitable for holding the antifouling sheet, preferably, the holder comprises a slot configured to receive the antifouling sheet, a combination according to any of claims 7 to 11 The housing or the sensor unit comprises a holder suitable for holding the antifouling sheet, preferably, the holder comprises a slot configured to receive the antifouling sheet, a combination according to any of claims 7 to 11 The housing or the sensor unit comprises a holder suitable for holding the antifouling sheet, preferably, the holder comprises a slot configured to receive the antifouling sheet, a combination according to any of claims 7 to 11

13. The control unit provides means for an operator to control the distance between the glass substrate and the CVD coater, a combination according to any of claims 2 to 12 The control unit provides means for an operator to control the distance between the glass substrate and the CVD coater, a combination according to any of claims 2 to 12

14. The control unit is configured to warn the operator when the CVD coater is closer to the glass substrate than a predetermined minimum distance, a combination according to any of claims 2 to 13 The control unit is configured to warn the operator when the CVD coater is closer to the glass substrate than a predetermined minimum distance, a combination according to any of claims 2 to 13 The control unit is configured to warn the operator when the CVD coater is closer to the glass substrate than a predetermined minimum distance, a combination according to any of claims 2 to 13

15. The combination is suitable for use during the manufacturing process of float glass, a combination according to any of claims 2 to 14 The combination is suitable for use during the manufacturing process of float glass, a combination according to any of claims 2 to 14

16. A capacitive proximity sensor for attachment to a CVD coater, comprising A sensor unit, A control unit, and The capacitive proximity sensor is configured to determine the distance between the glass substrate and the CVD coater, and At least a part of the sensor unit is protected from the surrounding atmosphere by an antifouling coating and / or an antifouling sheet A capacitive proximity sensor, wherein at least a part of the sensor unit is protected from the surrounding atmosphere by an antifouling coating and / or an antifouling sheet A capacitive proximity sensor, wherein at least a part of the sensor unit is protected from the surrounding atmosphere by an antifouling coating and / or an antifouling sheet

17. A process for determining the distance between a glass substrate and a CVD coater, comprising i) providing a glass substrate, and a combination of a CVD coater and a capacitive proximity sensor according to any of claims 1 to 14, ii) using the capacitive proximity sensor to determine the distance between the glass substrate and the CVD coater A process for determining the distance between a glass substrate and a CVD coater, comprising i) providing a glass substrate, and a combination of a CVD coater and a capacitive proximity sensor according to any of claims 1 to 14, ii) using the capacitive proximity sensor to determine the distance between the glass substrate and the CVD coater A process for determining the distance between a glass substrate and a CVD coater, comprising i) providing a glass substrate, and a combination of a CVD coater and a capacitive proximity sensor according to any of claims 1 to 14, ii) using the capacitive proximity sensor to determine the distance between the glass substrate and the CVD coater

18. The process according to claim 17, which is carried out when the temperature of the glass substrate is within the range of 450°C to 800°C, preferably within the range of 550°C to 770°C. **Claim 19** Use of a capacitive proximity sensor for determining the distance between a glass substrate and a CVD coater. **Claim 20** Use of an anti-fouling coating and / or an anti-fouling sheet for protecting a capacitive proximity sensor attached to a CVD coater. ​

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