Glass article manufacturing device and manufacturing method

Abstract

The invention provides a manufacturing device and a manufacturing method of a glass article, which can restrain foreign matter defects on the glass article. A device (1) for manufacturing a glass article is provided with: a transfer tube (14) for transferring molten glass (Gm); and a holding brick (24) that is disposed on the outer peripheral side of the transfer tube (14) and holds the transfer tube (14). The transfer tube (14) is provided with a tubular portion (16) and a flange portion (17) provided at an end portion (16a) of the tubular portion (16), and the end portion (16a) of the tubular portion (16) and the flange portion (17) are exposed from the holding brick (24). A cover member (28) that covers an end portion (16a) of the tubular portion (16) from the outside in a state in which the flange portion (17) is housed is provided in a portion exposed from the holding brick (24).

Description

Technical Field

[0001] The present invention relates to a manufacturing device and a manufacturing method for glass products such as plate glass. Background Art

[0002] The manufacturing device of glass articles comprises: a transfer pipe for transferring molten glass so as to supply molten glass generated by a glass melting furnace to a forming device; and a holding brick which is arranged on the outer peripheral side of the transfer pipe and holds the transfer pipe (for example, refer to Patent Documents 1 and 2). Generally, the manufacturing device of glass articles comprises a plurality of groups of transfer pipes and holding bricks, and the ends of the transfer pipes of adjacent groups are connected to each other.

[0003] Each transfer pipe includes a tubular portion and a flange portion provided at the end of the tubular portion. The middle portion of the tubular portion in the longitudinal direction is surrounded by the retaining bricks. On the other hand, the end of the tubular portion in the longitudinal direction and the flange portion are not surrounded by the retaining bricks but are exposed from the retaining bricks.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-19629

[0007] Patent Document 2: Japanese Patent Application Publication No. 2019-108258 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, since the end portion and the flange portion of the tubular portion of the transfer pipe are exposed from the holding brick, foreign matter defects (for example, tin oxide) may occur in the manufactured glass article.

[0010] Here, the cause of the foreign matter defect is inferred as follows. That is, an air layer is sometimes formed inside the transfer pipe at the position corresponding to the end of the tubular portion and the flange portion exposed from the retaining brick. And, sometimes, a part of the components (such as SnO2) in the molten glass transferred inside the transfer pipe volatilizes into the air layer. However, the end of the transfer pipe exposed from the retaining brick and the flange portion are easily cooled by external air, especially in winter. As a result, it is believed that the components such as SnO2 volatilized into the air layer are cooled and solidified and mixed into the molten glass, and foreign matter defects such as tin oxide are generated in the glass article. It should be noted that SnO2 is added to the molten glass as a clarifier, for example.

[0011] An object of the present invention is to suppress the generation of foreign matter defects in glass articles.

[0012] Solutions to Solve Problems

[0013] (1) The present invention made in order to solve the above-mentioned problems is a manufacturing device for glass articles, comprising: a transfer pipe that transfers molten glass; and a holding brick that is arranged on the outer peripheral side of the transfer pipe and holds the transfer pipe, and the manufacturing device for glass articles is characterized in that the transfer pipe has a tubular portion and a flange portion provided at the end of the tubular portion, the end of the tubular portion and the flange portion are exposed from the holding brick, and the portion exposed from the holding brick is provided with a cover member that covers the end of the tubular portion from the outside while the flange portion is accommodated inside.

[0014] Thus, the tubular portion and flange of the transfer pipe exposed from the holding brick are kept warm by the cover member, thereby suppressing cooling of the tubular portion and flange of the transfer pipe exposed from the holding brick by the outside air, and suppressing the occurrence of foreign matter defects in the glass article.

[0015] (2) In the configuration of (1) above, it is preferred that the apparatus for manufacturing a glass article includes a housing that accommodates and fixes the holding brick inside, and the cover member is disposed along the housing.

[0016] In this way, the cover member can be easily arranged. In addition, an appropriate space can be formed between the cover member and the transfer pipe.

[0017] (3) In the structure of (1) or (2) above, the transfer pipe preferably has a cooling device for cooling the flange portion by circulating gas, and the gas used for cooling the flange portion is discharged into the space between the cover member and the transfer pipe.

[0018] In this way, the heat loss of the flange portion can be suppressed by cooling by the cooling device. In addition, the gas used for cooling the flange portion becomes relatively high in temperature. Therefore, when the gas used for cooling the flange portion is discharged to the space between the cover member and the transfer pipe, the heat insulation effect of the tubular portion of the transfer pipe exposed from the retaining brick and the flange portion can be improved.

[0019] (4) In the structure of (3) above, it is preferred that the flange portion comprises a first flange portion and a second flange portion arranged opposite to the first flange portion, and the exhaust direction of the gas used in cooling the first flange portion and the exhaust direction of the gas used in cooling the second flange portion are different from each other.

[0020] In this way, the temperature of the space between the cover member and the transfer pipe can be easily uniformized, and the heat insulation effect of the tubular portion and the flange portion of the transfer pipe exposed from the retaining brick can be stabilized.

[0021] (5) In the structure of any one of the above (1) to (4), it is preferable that the cover member is made of heat-resistant cloth.

[0022] In this way, the cover member can ensure appropriate air permeability, thereby preventing the inflow of external air and discharging the gas used for cooling to the outside of the cover member. Therefore, it is possible to prevent the space between the cover member and the transfer pipe from being over-supplied with the gas used for cooling.

[0023] (6) The present invention made to solve the above-mentioned problems is a method for manufacturing glass products, characterized in that the method for manufacturing glass products includes a step of transferring molten glass using a transfer pipe possessed by a glass product manufacturing device having the structure of any one of the above-mentioned (1) to (5).

[0024] In this way, the same effects as those of the corresponding structures already described can be enjoyed.

[0025] Effects of the Invention

[0026] According to the present invention, it is possible to suppress the occurrence of foreign matter defects in glass products. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a side view showing a manufacturing apparatus for a glass article according to a first embodiment of the present invention.

[0028] Figure 2 It is a cross-sectional view showing the periphery of the connection portion between the first transfer pipe and the second transfer pipe.

[0029] Figure 3 yes Figure 2 Magnified view of the X region in FIG.

[0030] Figure 4 It is a perspective view showing the end portion of the first transfer pipe.

[0031] Figure 5 yes Figure 2 YY section view.

[0032] Figure 6 yes Figure 2 ZZ section view.

[0033] Figure 7 It is a cross-sectional view showing the vicinity of a connection portion between adjacent transfer pipes in a manufacturing apparatus for a glass article according to a second embodiment of the present invention.

[0034] Figure 8 It is a cross-sectional view showing the vicinity of a connection portion between adjacent transfer pipes in a glass article manufacturing apparatus according to a third embodiment of the present invention.

[0035] Description of Reference Numerals

[0036] 1. Manufacturing device

[0037] 2 Melting furnace

[0038] 3Transfer device

[0039] 4 Forming device

[0040] 5 Clarification tank

[0041] 6 Mixing tank

[0042] 7 cauldron

[0043] 8 Upstream connection pipeline

[0044] 9Midstream connecting pipeline

[0045] 10 Cooling pipes

[0046] 11 formed body

[0047] 14First transfer pipe

[0048] 15 Second transfer pipe

[0049] 16, 20 tubular part

[0050] 17, 21 flange

[0051] 18, 22 electrode part

[0052] 19, 23 cooling devices

[0053] 24, 26 keep brick

[0054] 25, 27 shell

[0055] 28 cover component

[0056] 29, 33 cooling flow path

[0057] 30, 34 inlet

[0058] 31, 35 outflow

[0059] 32, 36 Cooling pipes

[0060] 37 Felt

[0061] C Gas

[0062] Cx Used gas (exhaust)

[0063] Gm molten glass

[0064] Gr Glass Ribbon

[0065] S space. DETAILED DESCRIPTION

[0066] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that the same reference numerals are used for the corresponding components in each embodiment, so that repeated descriptions are sometimes omitted. In the case where only a part of the structure is described in each embodiment, the structure of other embodiments previously described can be applied to the other parts of the structure. In addition, not only the combination of structures explicitly stated in the description of each embodiment, but also the structures of multiple embodiments can be partially combined with each other even if not explicitly stated, as long as there is no particular obstacle to the combination.

[0067] (First Embodiment)

[0068] like Figure 1 As shown, the manufacturing device 1 of the glass article of the first embodiment comprises: a melting furnace 2, which is arranged at the upstream end and heats the glass raw materials to generate molten glass Gm; a transfer device 3, which transfers the molten glass Gm flowing out of the melting furnace 2 toward the downstream side; and a forming device 4, which uses the molten glass Gm supplied from the transfer device 3 to form a glass ribbon Gr.

[0069] The transfer device 3 includes a clarification tank 5, a stirring tank 6, and a kettle 7 in order from the upstream side. The inflow portion 5a of the clarification tank 5 is connected to the outflow portion 2b of the melting furnace 2 via an upstream connecting pipe 8. The outflow portion 5b of the clarification tank 5 is connected to the inflow portion 6a of the stirring tank 6 via a midstream connecting pipe 9. The outflow portion 6b of the stirring tank 6 is connected to the inflow portion 7a of the kettle 7 via a cooling pipe 10.

[0070] The clarification tank 5 performs clarification treatment on the molten glass Gm generated by the melting furnace 2. The stirring tank 6 stirs the molten glass Gm that has been subjected to the clarification treatment and performs homogenization treatment. The cooling duct 10 cools the molten glass Gm that has been subjected to the homogenization treatment and adjusts its viscosity, etc. The kettle 7 further adjusts the viscosity, flow rate, etc. of the cooled molten glass Gm. It should be noted that a plurality of stirring tanks 6 may also be configured in the transfer path of the transfer device 3.

[0071] The forming device 4 includes a forming body 11 that forms a ribbon by flowing molten glass Gm down by an overflow down-draw method, and a large-diameter introduction pipe 12 that introduces molten glass Gm into the forming body 11. The molten glass Gm is supplied to the introduction pipe 12 from the kettle 7 of the transfer device 3 through a small-diameter pipe 13.

[0072] The glass ribbon Gr formed into a ribbon shape is cut into a predetermined size by a cutting device after passing through an annealing furnace, and becomes a plate glass as a glass article. Plate glass has a thickness of, for example, 0.01 to 2 mm, and is used in glass substrates and cover glass of displays such as liquid crystal displays and organic EL displays. It should be noted that the forming device 4 can perform other down-drawing methods such as a slit down-drawing method, and can also perform methods other than the down-drawing method such as a float method.

[0073] As a material of the plate glass, for example, silicate glass, silica glass, borosilicate glass, soda-lime glass, aluminosilicate glass, alkali-free glass, aluminosilicate glass, etc. are used.

[0074] As a glass composition, the alkali-free glass preferably contains, by mass%, 50 to 70% SiO2, 12 to 25% Al2O3, 0 to 12% B2O3, 0 to 1% Li2O+Na2O+K2O (the total amount of Li2O, Na2O and K2O), 0 to 8% MgO, 0 to 15% CaO, 0 to 12% SrO, 0 to 15% BaO, and 0.01 to 1.5% SnO2. If it is such a glass composition, it is suitable for a glass substrate for a display.

[0075] The aluminosilicate glass preferably contains, by mass%, 40% to 70% SiO2, 10% to 30% Al2O3, 0% to 3% B2O3, 5% to 25% Na2O, 0% to 5.5% K2O, 0.1% to 10% Li2O, 0% to 5.5% MgO, 2% to 10% P2O5, and 0.01 to 1.5% SnO2 as a glass composition. With such a glass composition, it is easy to achieve both ion exchange performance and devitrification resistance at a high level, and it is suitable for chemically strengthened glass, especially cover glass for displays.

[0076] The clarification tank 5, stirring tank 6, kettle 7, upstream connecting pipe 8, midstream connecting pipe 9 and cooling pipe 10 of the transfer device 3 are all composed of transfer pipes. The ends of two adjacent transfer pipes on the transfer path of the transfer device 3 are connected to each other. It should be noted that the clarification tank 5, stirring tank 6, kettle 7, upstream connecting pipe 8, midstream connecting pipe 9 and cooling pipe 10 can each be composed of one transfer pipe, but can also be composed by connecting multiple transfer pipes. These transfer pipes are described in detail below.

[0077] Figure 2 Two transfer pipes adjacent to each other on the transfer path of the transfer device 3 are shown. Here, the transfer pipe located on the upstream side is referred to as the first transfer pipe 14, and the transfer pipe located on the downstream side is referred to as the second transfer pipe 15. Figure 2 , the vicinity of the connection portion between the downstream end portion of the first transfer pipe 14 and the upstream end portion of the second transfer pipe 15 is illustrated.

[0078] As specific examples of the first transfer pipe 14 and the second transfer pipe 15, the following examples can be cited. For example, (1) the first transfer pipe 14 is the upstream connection pipe 8 and the second transfer pipe 15 is the clarification tank 5, (2) the first transfer pipe 14 is the clarification tank 5 and the second transfer pipe 15 is the midstream connection pipe 9, etc. Or in the case where a plurality of transfer pipes are connected to form the clarification tank 5, the upstream connection pipe 8, the midstream connection pipe 9 and the cooling pipe 10, for example, the first transfer pipe 14 is a part of the upstream side of the clarification tank 5 and the second transfer pipe 15 is a part of the downstream side of the clarification tank 5, etc. can be cited.

[0079] The first transfer pipe 14 includes a tubular portion 16, a flange portion (first flange portion) 17 provided at one end (upstream end portion 20a) and the other end (downstream end portion 16a) in the longitudinal direction of the tubular portion 16, an electrode portion 18, and a cooling device 19 for cooling the flange portion 17. Similarly, the second transfer pipe 15 includes a tubular portion 20, a flange portion (second flange portion) 21 provided at one end (upstream end portion 20a) and the other end (downstream end portion) in the longitudinal direction of the tubular portion 20, an electrode portion 22, and a cooling device 23 for cooling the flange portion 21.

[0080] The tubular parts 16 and 20 are, for example, in the shape of a circular tube. The tubular parts 16 and 20 are made of platinum, a platinum alloy, reinforced platinum, a reinforced platinum alloy, etc. The molten glass Gm is transferred to the downstream side inside the tubular parts 16 and 20 .

[0081] The flange portions 17 and 21 are, for example, in the shape of a disk. The flange portions 17 and 21 are formed to surround the entire circumference of the outer circumference of the tubular portions 16 and 20. In the present embodiment, the flange portion 17 of the first transfer pipe 14 includes an annular inner flange portion 17a provided on the outer circumference of the tubular portion 16 and a tubular outer flange portion 17b provided on the outer circumference of the inner flange portion 17a. The flange portion 21 of the second transfer pipe 15 includes an annular inner flange portion 21a provided on the outer circumference of the tubular portion 16 and a tubular outer flange portion 21b provided on the outer circumference of the inner flange portion 21a. The inner flange portions 17a and 21a are made of platinum, a platinum alloy, reinforced platinum, a reinforced platinum alloy, etc. The outer flange portions 17b and 21b are made of nickel, a nickel alloy, etc.

[0082] The electrode parts 18 and 22 are, for example, plate-shaped. The electrode parts 18 and 22 are made of nickel, nickel alloy, etc. In the present embodiment, the electrode parts 18 and 22 are mounted on the flange parts 17 and 21 (outer flange parts 17b and 21b). In the present embodiment, the electrode part 18 of the first transfer tube 14 is arranged to protrude upward from the flange part 17, and the electrode part 22 of the second transfer tube 15 is arranged to protrude downward from the flange part 21. It should be noted that the protruding direction of the electrode parts 18 and 22 is not particularly limited. The electrode parts 18 and 22 penetrate the cover member 28 described later, and are connected to an electric wire not shown in the figure on the outside of the cover member 28.

[0083] The first transfer pipe 14 and the second transfer pipe 15 are connected by a flange portion 17 provided at the downstream end portion of the first transfer pipe 14 and a flange portion 21 provided at the upstream end portion of the second transfer pipe 15 in a state where the flange portions 17 face each other.

[0084] The middle portion 16b of the tubular portion 16 of the first transfer pipe 14 in the longitudinal direction is held by a retaining brick 24. The retaining brick 24 is arranged so as to surround the entire circumference of the outer peripheral portion of the tubular portion 16. The retaining brick 24 is fixed to the outer casing 25 while being accommodated inside the metal outer casing 25. On the other hand, the downstream end 16a of the tubular portion 16 of the first transfer pipe 14 and the flange portion 17 are exposed from the retaining brick 24 while protruding from the retaining brick 24 to the downstream side. The length of the downstream end 16a of the tubular portion 16 of the first transfer pipe 14 (the length of the exposed portion of the tubular portion 16) is, for example, 1 to 50 m. It should be noted that, although not shown in the figure, the upstream end of the tubular portion 16 of the first transfer pipe 14 and the flange portion provided at the upstream end are also exposed from the retaining brick 24 while protruding from the retaining brick 24 to the upstream side.

[0085] The middle portion 20b of the tubular portion 20 of the second transfer pipe 15 in the longitudinal direction is held by a retaining brick 26. The retaining brick 26 is arranged so as to surround the entire circumference of the outer peripheral portion of the tubular portion 20. The retaining brick 26 is housed inside a metal housing 27. On the other hand, the upstream end portion of the tubular portion 20 of the second transfer pipe 15 and the flange portion 21 are exposed from the retaining brick 26 in a state of protruding from the retaining brick 26 to the upstream side. The length of the upstream end portion of the tubular portion 20 of the second transfer pipe 15 (the length of the exposed portion of the tubular portion 20) is, for example, 1 to 50 mm. It should be noted that, although not shown in the figure, the downstream end portion of the tubular portion 20 of the second transfer pipe 15 and the flange portion provided at the downstream end portion are also exposed from the retaining brick 26 in a state of protruding from the retaining brick 26 to the downstream side.

[0086] The downstream end 16a of the tubular portion 16 of the first transfer pipe 14 and the upstream end 20a of the tubular portion 20 of the second transfer pipe 15 are covered by the cover member 28 in the portion exposed from the retaining bricks 24 and 26. In this state, the cover member 28 is arranged to surround the entire circumference of the end portions 16a and 20a of the tubular portions 16 and 20 while accommodating the flange portions 17 and 21 therein.

[0087] In the present embodiment, the cover member 28 is arranged along the respective housings 25 and 27 while being bridged between the housing 25 of the first transfer pipe 14 and the housing 27 of the second transfer pipe 15. More specifically, the cover member 28 is arranged while being wound along the circumferential direction of the housings 25 and 27.

[0088] The cover member 28 is arranged separately from the ends 16a, 20a of the tubular portions 16, 20 and the flange portions 17, 21 in such a manner that a space S is sandwiched therebetween. The space S is a closed space. The intrusion of external air into the space S is prevented by the cover member 28. Therefore, the ends 16a, 20a of the tubular portions 16, 20 and the flange portions 17, 21 are kept warm by the space S. Figure 3 As shown, even if an air layer A is formed inside the first transfer pipe 14 and the second transfer pipe 15 in the portion exposed from the retaining bricks 24 and 26, the air layer A is not improperly cooled by the outside air. As a result, it is possible to suppress the generation of foreign matter defects such as tin oxide in the plate glass due to the cooling of the air layer A. It should be noted that the air layer A is easily formed when, for example, the inner surface of the connection portion between the tubular portion 16 and the flange portion 17 of the first transfer pipe 14 and the inner surface of the connection portion between the tubular portion 20 and the flange portion 21 of the second transfer pipe 15 are bent outward.

[0089] The cover member 28 is made of a metal plate, heat-resistant cloth, etc. However, in the case of heat-resistant cloth, compared with a metal plate, it is easier to fill the gap in the space S and improve the heat retention. As the heat-resistant cloth, for example, glass cloth can be cited.

[0090] like Figure 4 as well as Figure 5 As shown, the cooling device 19 of the first transfer pipe 14 has a cooling flow path 29 for circulating a cooling gas C such as air. The cooling flow path 29 is formed inside the outer flange portion 17b. The cooling flow path 29 includes a first cooling flow path 29a and a second cooling flow path 29b that constitute independent flow paths. The number and shape of the flow paths constituting the cooling flow path 29 are not particularly limited and can be appropriately set according to the size of the flange portion 17. In addition, the cooling flow path 29 may not be formed inside the flange portion 17, but may be formed on the surface using piping or the like.

[0091] The first cooling channel 29a and the second cooling channel 29b are provided with an inlet 30 and an outlet 31 for the gas C. The inlet 30 of each cooling channel 29a, 29b is provided at the upper portion of the outer flange portion 17b. The position of the inlet 30 is not particularly limited, and it may also be provided at the side or lower portion of the outer flange portion 17b. A cooling pipe 32 for transferring the gas C is connected to the inlet 30 of each cooling channel 29a, 29b. The cooling pipe 32 passes through the cover member 28, and is connected to a gas supply source (not shown) outside the cover member 28.

[0092] The outlet 31 of each cooling channel 29a, 29b is provided on the upper part of the outer flange portion 17b, and ejects upward the used gas (exhaust gas) Cx used for cooling the flange portion 17. That is, the used gas Cx discharged from the outlet 31 into the space S is discharged upward.

[0093] like Figure 6 As shown, the cooling device 23 of the second transfer pipe 15 has substantially the same structure as the cooling device 19 of the first transfer pipe 14. That is, the cooling device 23 of the second transfer pipe 15 has a cooling flow path 33 formed inside the outer flange portion 21b and through which a cooling gas C such as air flows. The cooling flow path 33 includes a first cooling flow path 33a and a second cooling flow path 33b that constitute independent flow paths. The number and shape of the flow paths constituting the cooling flow path 33 are not particularly limited and can be appropriately set according to the size of the flange portion 21. In addition, the cooling flow path 33 may not be formed inside the flange portion 21, but may be formed on the surface using piping or the like.

[0094] The first cooling channel 33a and the second cooling channel 33b are provided with an inlet 34 and an outlet 35 for the gas C. The inlet 34 of each cooling channel 33a, 33b is provided at the lower part of the outer flange portion 21b. The position of the inlet 34 is not particularly limited, and it may also be provided at the side or upper part of the outer flange portion 21b. A cooling pipe 36 for transferring the gas C is connected to the inlet 34 of each cooling channel 33a, 33b. The cooling pipe 36 passes through the cover member 28 and is connected to a gas supply source (not shown) outside the cover member 28.

[0095] The outlet 35 of each cooling flow path 33a, 33b is provided at the lower part of the outer flange portion 21b, and ejects the used gas (exhaust gas) Cx used for cooling the flange portion 21 downward. That is, the exhaust direction of the used gas Cx exhausted from the outlet 35 into the space S is downward. Therefore, in the space S, the exhaust direction of the used gas Cx of the cooling device 19 of the first transfer pipe 14 and the exhaust direction of the used gas Cx of the cooling device 23 of the second transfer pipe 15 are different from each other.

[0096] The used gas Cx used in cooling has a relatively high temperature and is higher than the outside air. Therefore, if it is supplied from the cooling devices 19 and 23 into the space S, the heat preservation of the space S is improved. As a result, it is possible to suppress an inappropriate temperature drop of the end portions 16a and 20a of the tubular portions 16 and 20 and the flange portions 17 and 21 exposed from the retaining bricks 24 and 26. The temperature of the space S is preferably 100 to 500°C, for example.

[0097] In addition, the exhaust direction of the used gas Cx of the cooling device 19 of the first transfer pipe 14 and the exhaust direction of the used gas Cx of the cooling device 23 of the second transfer pipe 15 in the space S are different from each other, so the used gas Cx is fully filled in the space S, and the heat preservation effect of the space S becomes uniform. It should be noted that as long as the exhaust direction of the used gas Cx of the cooling device 19 of the first transfer pipe 14 and the exhaust direction of the used gas Cx of the cooling device 19 of the second transfer pipe 15 are different from each other in the space S, the direction of each exhaust direction is not particularly limited.

[0098] Furthermore, when the cover member 28 is formed of heat-resistant cloth, appropriate air permeability can be ensured in the cover member 28. If the used gas Cx is discharged into the space S, the pressure in the space S is likely to be relatively higher than the pressure outside the cover member 28. As a result, the used gas CX discharged into the space S can be gradually discharged to the outside of the cover member 28 through the cover member 28, and the pressure in the space S can be prevented from excessively rising. It should be noted that, when the cover member 28 has air permeability, even when the pressure in the space S is relatively higher than the pressure outside the cover member 28, the intrusion of external gas into the space S is also suppressed.

[0099] Next, a method for producing a glass article using the production apparatus 1 configured as described above will be described.

[0100] The manufacturing method includes a melting step, a molten glass transferring step, a forming step, an annealing step, and a cutting step.

[0101] In the melting step, the glass-making raw materials supplied into the melting furnace 2 are heated to generate molten glass Gm.

[0102] It is preferable that the molten glass Gm contains 0.01-1.5 mass % of SnO 2. In this way, in the clarification process included in the molten glass transferring process, the degassing of the molten glass Gm becomes easy.

[0103] In the molten glass transfer process, the molten glass Gm of the melting furnace 2 is sequentially transferred to the clarification tank 5, the stirring tank 6, the kettle 7 and the forming body 11 via the upstream connecting pipe 8, the midstream connecting pipe 9 and the cooling pipe 10. That is, the molten glass transfer process includes a clarification process, a homogenization process and a state adjustment process. In the clarification process, in the clarification tank 5, gas (bubbles) is generated from the molten glass Gm under the action of the clarifier deployed to the glass raw material. The gas is discharged from the clarification tank 5 to the outside. In the homogenization process, in the stirring tank 6, the molten glass Gm is stirred and homogenized. In the state adjustment process, in the cooling pipe 10 and the kettle 7, the state (e.g., viscosity, flow) of the molten glass Gm is adjusted.

[0104] Furthermore, in the molten glass transfer process, Figure 2 as well as Figure 5 As shown, the cover member 28 is arranged to heat the end portions 16a and 20a of the tubular portions 16 and 20 and the flange portions 17 and 21 exposed from the holding bricks 24 and 26, so that the occurrence of foreign matter defects in the manufactured plate glass can be suppressed.

[0105] The temperature of the molten glass Gm in the outflow portion 5b of the clarification tank 5 is higher than the temperature of the molten glass Gm in the inflow portion 5a of the clarification tank 5, for example, 1300°C or more. That is, in the outflow portion 5b of the clarification tank 5, the temperature of the molten glass Gm becomes high temperature and it is particularly easy to volatilize SnO2, etc., which is the cause of the generation of foreign matter defects. Therefore, it is preferable to arrange the cover member 28 around the connection portion between the clarification tank 5 and the midstream connection pipe 9.

[0106] In the forming step, the molten glass Gm after the molten glass transfer step is supplied to the forming body 11. The forming body 11 allows the molten glass Gm to overflow from the overflow channel and flow down along the side wall surface thereof. The forming body 11 allows the flowing molten glass Gm to merge at the lower end, thereby forming a band-shaped glass ribbon Gr.

[0107] After that, the band-shaped glass ribbon Gr is subjected to an annealing process in an annealing furnace and a cutting process in a cutting device to cut out plate glass of a predetermined size. Through the above, high-quality plate glass with very few defects caused by foreign matter defects is completed.

[0108] (Second Embodiment)

[0109] like Figure 7As shown, in the manufacturing device 1 and manufacturing method of the glass article according to the second embodiment of the present invention, the exhaust direction of the used gas Cx of the cooling device 19 of the first transfer pipe 14 and the exhaust direction of the used gas Cx of the cooling device 23 of the second transfer pipe 15 are in the same direction (upward in the example shown in the figure) in the space S formed by the cover member 28. Even in this case, the heat preservation in the space S is improved, and the inappropriate temperature drop of the end portions 16a, 20a of the tubular portions 16, 20 and the flange portions 17, 21 exposed from the retaining bricks 24, 26 can be suppressed.

[0110] (Third Embodiment)

[0111] like Figure 8 As shown, in the manufacturing device 1 and manufacturing method of the glass article of the third embodiment of the present invention, a felt 37 as a heat-insulating member is arranged on the outer peripheral surface of the first transfer pipe 14 and the outer peripheral surface of the second transfer pipe 15 in the space S formed by the cover member 28. In this way, the heat-insulating property of the end portions 16a, 20a of the tubular portions 16, 20 and the flange portions 17, 21 exposed from the retaining bricks 24, 26 can be further improved by the felt 37. It should be noted that the felt 37 may be arranged only on one of the outer peripheral surface of the first transfer pipe 14 and the outer peripheral surface of the second transfer pipe 15.

[0112] As the felt 37, for example, a felt made of a fire-resistant fiber material can be used. Specifically, a felt having heat resistance to withstand a temperature of 1000° C. or higher (preferably 1300° C. or higher) and elasticity can be used. For example, a felt made of alumina fiber, silica fiber, zirconia fiber, or a blended fiber thereof can be used.

[0113] It should be noted that the present invention is not limited to the configuration of the above-described embodiment, nor is it limited to the above-described effects. The present invention can be modified in various ways without departing from the gist of the present invention.

[0114] In the above-mentioned embodiment, at least one of the used gas Cx of the cooling device 19 of the first transfer pipe 14 and the used gas Cx of the cooling device 23 of the second transfer pipe 15 may be directly discharged to the outside of the cover member 28 using a pipe or the like. In other words, the used gas Cx of the cooling devices 19 and 23 may not be supplied to the space S. That is, even if the external air is blocked only by the cover member 28, an inappropriate temperature drop of the end portions 16a and 20a of the tubular portions 16 and 20 and the flange portions 17 and 21 exposed from the retaining bricks 24 and 26 can be suppressed.

[0115] In the above-mentioned embodiment, a cooling device may be provided to cool at least one of the electrode portion 18 of the first transfer pipe 14 and the electrode portion 22 of the second transfer pipe 15. The cooling device of the electrode portions 18 and 22 may also serve as a cooling device of the flange portions 17 and 21. For example, if a cooling pipe for supplying the gas C to the flange portions 17 and 21 is brought into close contact with the surface of the electrode portions 18 and 22, the electrode portions 18 and 22 and the flange portions 17 and 21 can be cooled simultaneously.

[0116] In the above-mentioned embodiment, the glass article is described as a plate glass, but the present invention is not limited thereto. The glass article may be, for example, a glass roll obtained by winding a ribbon-shaped glass ribbon into a roll, an optical glass component, a glass tube, a glass block, a glass fiber, or the like.

Claims

1. A glass article manufacturing device, comprising: a transfer pipe for transferring molten glass; and a holding brick disposed on the outer peripheral side of the transfer pipe and holding the transfer pipe, The manufacturing device of the glass article is characterized in that: The transfer pipe includes a tubular portion and a flange portion provided at an end of the tubular portion, and the end of the tubular portion and the flange portion are exposed from the holding brick. A cover member is provided at a portion exposed from the holding brick, the cover member covering the end portion of the tubular portion from the outside in a state where the flange portion is accommodated inside.

2. The manufacturing device for glass articles according to claim 1, wherein: The glass article manufacturing device includes a housing for accommodating and fixing the holding brick inside. The cover member is arranged along the housing.

3. The manufacturing device for glass articles according to claim 1 or 2, wherein: The transfer pipe has a cooling device that allows gas to flow to cool the flange portion. The gas used for cooling the flange portion is discharged into a space between the cover member and the transfer pipe.

4. The manufacturing device for glass articles according to claim 3, wherein: The flange portion includes a first flange portion and a second flange portion disposed opposite to the first flange portion. The exhaust direction of the gas used for cooling the first flange portion and the exhaust direction of the gas used for cooling the second flange portion are different from each other.

5. The manufacturing device for glass articles according to claim 1 or 2, wherein: The cover member is made of heat-resistant cloth.

6. A method for manufacturing a glass article, wherein: The method for producing a glass article includes the step of transferring molten glass using the transfer pipe included in the apparatus for producing a glass article according to claim 1 or 2.

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