JP6708968B2 - Sheet glass manufacturing apparatus and sheet glass manufacturing method - Google Patents

Description

The present invention relates to an apparatus and a method for manufacturing flat glass.

As is well known, flat glass used in various fields is represented by a glass substrate for a flat panel display (FPD) such as a liquid crystal display (LCD), a plasma display (PDP), and an organic EL display (OLED). In reality, strict product quality is required for surface defects and undulations.

In order to meet such requirements, the downdraw method is widely used as a method for manufacturing flat glass. As this downdraw method, an overflow downdraw method and a slot downdraw method are known.

The overflow down draw method is to pour molten glass into an overflow groove provided at the upper part of a molded body having a substantially wedge-shaped cross section, and to flow the molten glass overflowing from the overflow groove to both sides along side walls on both sides of the molded body. While flowing down, they are fused and integrated at the lower end of the molded body to continuously mold one sheet of glass. Further, the slot down draw method is one in which a slot-shaped opening is formed in the bottom wall of a molded body to which molten glass is supplied, and a single glass sheet is continuously molded by flowing molten glass through this opening. Is.

Especially in the overflow down draw method, the front and back surfaces of the molded sheet glass are molded without contacting any part of the molded body during the molding process, so that the flatness is very good and there are no defects such as scratches. Becomes

As a plate glass manufacturing apparatus using the overflow down draw method, as disclosed in Patent Document 1, a forming furnace having a formed body therein, a slow cooling furnace installed below the forming furnace, and a cooling provided below the slow cooling furnace are disclosed. Some have a section and a cutting section. This plate glass manufacturing apparatus overflows the molten glass from the top of the molded body, forms a plate glass (glass ribbon) by fusing at the lower end thereof, and passes the plate glass through an annealing furnace to remove its internal strain, After cooling to room temperature in the cooling unit, the cutting unit is configured to cut into a predetermined size.

JP 2012-197185 A

In the above plate glass manufacturing apparatus, in the glass melting furnace arranged on the upstream side of the forming furnace, the glass raw material is melted into molten glass, and the molten glass is supplied to the downstream forming furnace. A glass supply passage for transferring the molten glass to the forming furnace is provided between the melting furnace and the forming furnace. This glass supply path is formed by connecting a plurality of glass supply pipes made of metal such as platinum.

Since the molten glass transferred through the glass supply passage has a high temperature of 1600° C. or higher, the glass supply pipe is heated (preheated) in advance so that the molten glass can be transferred during the operation of the flat glass manufacturing apparatus. There is a need. In this case, if the glass supply pipes are heated while they are still connected (the state of the glass supply passage), the expansion of each glass supply pipe may damage the connecting portion. Therefore, it is desirable to heat the glass supply path in a state where each glass supply pipe is separated.

As described above, it is necessary to heat the glass supply pipe in a separated state and then connect the glass supply pipes to form a glass supply path, and then connect the forming furnace to the glass supply pipe. Further, it is necessary to position the annealing furnace with respect to this forming furnace. As described above, in the conventional sheet glass manufacturing apparatus, the preparatory work before forming the sheet glass is complicated, and it is necessary to improve the work efficiency.

The present invention has been made in view of the above circumstances, and provides a plate glass manufacturing apparatus capable of efficiently performing a preparatory work before forming a plate glass, and a plate glass manufacturing method using the plate glass manufacturing apparatus. The purpose is to

The present invention is for solving the above problems, a glass supply path formed by connecting a plurality of glass supply pipes for transferring molten glass, a forming furnace for forming the molten glass into plate glass, and the plate glass. A plate glass manufacturing apparatus comprising: a slow cooling furnace that has a roller for transferring and is installed on an installation floor, wherein the slow cooling furnace and the roller are configured to be positionally changeable with respect to the installation floor. To do.

According to this configuration, the annealing furnace and the roller are configured to be repositionable with respect to the installation floor, so that the annealing furnace and the roller can be easily positioned with respect to the molding furnace after the molding furnace is connected to the preheated glass supply path. be able to. As a result, the plate glass manufacturing apparatus according to the present invention can efficiently perform the preparatory work before forming the plate glass.

In the above structure, the roller is a cantilever roller that individually clamps each end portion in the width direction of the plate glass, and has a plurality of stages in the vertical direction and is supported by a frame to be a part of the roller unit. It is desirable to be configured. As described above, the roller is a cantilever roller, and the plurality of stages of rollers are unitized by the frame, so that the roller positioning work can be efficiently performed.

It is preferable that the flat glass manufacturing apparatus according to the present invention includes a support base that supports the annealing furnace and the roller unit so that the position of the roller unit can be changed with respect to the installation floor. According to this, by moving the support base with respect to the installation surface, it is possible to efficiently position the annealing furnace and the rollers with respect to the forming furnace.

In this case, the support base includes a first support base that supports the annealing furnace in a position changeable with respect to the installation floor, and a second support base that supports the roller unit in a position changeable with respect to the installation floor. Is desirable. In this way, by supporting the annealing furnace and the roller unit so that their positions can be changed by the separate support bases, it becomes possible to easily adjust the positional relationship between the annealing furnace and the rollers.

Further, it is preferable that the support base includes wheels that can roll on the installation floor and a lock mechanism that locks the wheels. With this configuration, the positions of the annealing furnace and the rollers can be easily changed, and the annealing furnace and the rollers can be reliably positioned at the desired positions.

Further, the support base may be configured to be able to change the positions of the annealing furnace and the roller unit along the width direction or the plate thickness direction of the plate glass. As a result, the annealing furnace and the roller can be accurately positioned with respect to the sheet glass formed by the forming furnace.

Further, it is desirable that the plate glass manufacturing apparatus includes a positioning device that positions the annealing furnace with respect to the forming furnace. As a result, the molding furnace and the annealing furnace can be accurately aligned.

The present invention is a method for manufacturing a sheet glass by the sheet glass manufacturing apparatus having the above-mentioned configuration, wherein the step of heating the plurality of glass supply tubes in a separated state and the glass supply by connecting the heated glass supply tubes A step of forming a path, a step of connecting the forming furnace to the glass supply path after forming the glass supply path, and a step of positioning the annealing furnace and the rollers with respect to the connected forming furnace. And a forming step of forming the sheet glass by the forming furnace while supplying the molten glass to the forming furnace by the glass supply passage.

According to this, by heating (preheating) the glass supply pipe in a separated state, damage to the glass supply pipe due to heating is prevented, and a forming furnace is connected to the glass supply passage formed by connecting the preheated glass supply pipes. After the connection, the annealing furnace and the roller can be easily positioned with respect to the forming furnace. Thereby, the plate glass manufacturing method according to the present invention can efficiently perform the preparatory work before forming the plate glass, and thus the plate glass can be manufactured efficiently.

According to the present invention, it is possible to efficiently perform the preparatory work before forming the glass sheet.

It is a front view showing the whole plate glass manufacturing device composition. It is a side view showing a forming furnace and a slow cooling furnace. It is a front view which shows 1 process of the plate glass manufacturing method. It is a front view which shows 1 process of the plate glass manufacturing method. It is a front view which shows 1 process of the plate glass manufacturing method. It is a front view which shows 1 process of the plate glass manufacturing method. It is a side view which shows 1 process of the plate glass manufacturing method. It is a side view which shows 1 process of the plate glass manufacturing method. It is a front view which shows 1 process of the plate glass manufacturing method. It is a front view which shows a part of plate glass manufacturing apparatus at the time of completion of positioning of an annealing furnace. It is a partial front view which shows other embodiment of the plate glass manufacturing apparatus.

Hereinafter, modes for carrying out the present invention will be described with reference to the drawings. 1 to 10 show a first embodiment of a plate glass manufacturing apparatus and a plate glass manufacturing method according to the present invention.

As shown in FIG. 1, the glass manufacturing apparatus according to the present embodiment includes a melting furnace 1, a refining tank 2, a homogenization tank (stirring tank) 3, a condition adjusting tank 4, and a forming furnace in order from the upstream side. 5, an annealing furnace (annealer) 7 having roller units 6a and 6b, and a glass supply path 8 for transferring the molten glass GM from the melting furnace 1 to the forming furnace 5 are mainly provided.

The melting furnace 1 is a container for performing a melting step of melting the input glass raw material to obtain the molten glass GM. The refining tank 2 is a container for performing a step (clarification step) of refining the molten glass GM supplied from the melting furnace 1 by the action of a refining agent or the like. The clarification tank 2 is connected to the melting furnace 1 and the homogenization tank 3 via a glass supply passage 8.

The homogenization tank 3 is a container for performing a homogenizing step of stirring the clarified molten glass GM with a stirring blade or the like to homogenize it. The homogenizing tank 3 is connected to the condition adjusting tank 4 by a glass supply passage 8. The state adjusting tank 4 is a container for performing a state adjusting step of adjusting the molten glass GM to a state suitable for molding. The condition adjusting tank 4 is connected to the homogenizing tank 3 and the forming furnace 5 by a glass supply passage 8.

The molding furnace 5 has a molded body 5a for molding the molten glass GM into a desired plate shape. In the present embodiment, the formed body 5a forms the molten glass GM into the plate glass GR by the overflow downdraw method. Specifically, as shown in FIG. 2, the molded body 5a has a substantially wedge-shaped cross section. The molded body 5a has an overflow groove 5b in the upper part thereof.

In the molded body 5a, after the molten glass GM is supplied to the overflow groove 5b by the glass supply path 8, the molten glass GM overflows from the overflow groove 5b, and along the side wall surfaces 5c and 5d on both sides of the molded body 5a. Let it flow down. The molded body 5a fuses the molten glass GM that has flowed down at the lower end portions 5e of the side wall surfaces 5c and 5d, and molds the flat glass GR. The molded body 5a is heated to a predetermined temperature by a heater arranged in the molding furnace 5. The molded body 5a may be one that executes another downdraw method such as the slot downdraw method.

As shown in FIG. 1, the forming furnace 5 is supported by a support 9 above the annealing furnace 7. The support base 9 supports the forming furnace 5 so that its position can be changed. The forming furnace 5 is supported by a support 9 so that the forming furnace 5 can approach and separate from the glass supply path 8.

The slow cooling furnace 7 has a heater on the inner surface of the furnace wall and has a space through which the plate glass GR can pass in the vertical direction. The slow cooling furnace 7 has an opening (not shown) in the furnace wall through which a part of the roller units 6a and 6b can be inserted and removed. The slow cooling furnace 7 is installed on the installation floor S, and the position can be changed on the installation floor S. That is, the lower part of the annealing furnace 7 is supported by a support base (hereinafter referred to as “first support base”) 10, and the first support base 10 has a plurality of wheels 11 (for example, bearings) and these wheels 11 individually. And a lock mechanism 12 for fixing.

Like the annealing furnace 7, the roller units 6a and 6b are installed on the installation floor S and can be changed in position with respect to the installation floor S. As shown in FIG. 1, the roller units 6a and 6b include a first roller unit 6a for sandwiching one end of the plate glass GR in the width direction and a second roller unit for sandwiching the other end of the plate glass GR in the width direction. 6b and. Each of the roller units 6a and 6b includes a roller device 13, a frame 14 that supports the roller device 13, and a support base (hereinafter, referred to as “second support base”) 15 that supports the frame 14.

The roller device 13 is configured to have a plurality of stages (three stages in the illustrated example) in the vertical direction. Each roller device 13 has a roller (annealer roller) 13a that holds the plate glass GR, a shaft portion 13b that supports the roller 13a, and a drive device 13c that drives the shaft portion 13b. As shown in FIG. 2, the roller 13a is configured as a roller pair arranged in parallel in the thickness direction of the plate glass GR. The pair of rollers 13a are configured to be able to approach and separate from each other. By moving the roller units 6a and 6b, each roller 13a is arranged in the slow cooling furnace 7 through the opening of the slow cooling furnace 7 or taken out of the slow cooling furnace 7.

The shaft portion 13b is made of metal and individually supports each roller 13a. As a result, each roller 13a is configured as a cantilever roller that can individually sandwich the end portion of the plate glass GR in the width direction. The drive device 13c includes an electric motor that rotates the shaft portion 13b.

The frame 14 has a plurality of rail portions (guide portions) 14a that support the roller device 13 in a positionally changeable manner, and a plurality of columns 14b that support each rail portion 14a. The rail portion 14a is provided at a use position where the roller 13a of the roller device 13 is projected from the frame 14 and the roller 13a is inserted into the annealing furnace 7, and a standby position where the roller 13a is retracted from the use position and accommodated in the frame 14. The position of the roller device 13 is changed. Specifically, the rail portion 14a is configured by an LM guide (registered trademark) that supports the drive device 13c of the roller device 13 so that the drive device 13c can move back and forth, but the configuration is not limited to this configuration. It should be noted that the position of the roller 13a in the annealing furnace 7 can be finely adjusted by the rail portion 14a.

The pillar 14b is formed of a metal square pillar, but is not limited to this. The pillars 14b support the rail portions 14a arranged in a plurality of upper and lower stages (three stages in the illustrated example) at predetermined intervals. The pillar 14 b is erected on the upper surface of the second support base 15. Thereby, the frame 14 is configured integrally with the second support base 15.

The second support base 15 is configured to be capable of changing its position on a floor (hereinafter referred to as “installation floor”) S on which the annealing furnace 7 is installed. That is, the second support base 15 has a plurality of wheels 16 (for example, bearings) that can roll on the installation floor S, and a lock mechanism 17 that individually fixes these wheels 16.

Hereinafter, a method of manufacturing the plate glass GR with the plate glass manufacturing apparatus having the above configuration will be described. In this method, after melting the raw material glass in the melting furnace 1 (melting step) to obtain the molten glass GM, a fining step by the fining tank 2 and a homogenizing step by the homogenizing tank 3 are performed on the molten glass GM in this order , And the condition adjusting process by the condition adjusting tank 4. Then, this molten glass GM is transferred to the forming furnace 5, and the sheet glass GR is formed from the molten glass GM by the forming process using the formed body 5a. After that, while the plate glass GR is transferred downward by the roller 13a in the slow cooling furnace 7, the internal strain of the plate glass GR is removed by slow cooling. After that, the plate glass GR is cut into a predetermined size (cutting step) or wound into a roll (winding step) in a downstream process.

The formed sheet glass GR has a thickness of 0.01 to 10 mm, for example, and is used for a flat panel display such as a liquid crystal display or an organic EL display, an organic EL lighting, a substrate for a solar cell, or a protective cover.

Before performing the series of steps as described above, it is necessary to heat the glass supply path 8, the forming furnace 5, the slow cooling furnace 7, etc. in advance (hereinafter referred to as "preheating step"). Hereinafter, the preheating process will be described with reference to FIGS. 3 to 10.

The glass supply passage 8 is configured by connecting a plurality of glass supply pipes 8a. As shown in FIG. 3, the preheating step is performed in a state where the glass supply passage 8 is separated for each glass supply pipe 8a. An electrode 8b as a heater is provided at the end of each glass supply tube 8a. In the preheating step, each glass supply pipe 8a is heated for a certain period of time by energizing this electrode 8b.

Each glass supply pipe 8a is expanded by this heating. When the heating is completed, the separated glass supply pipes 8a are connected to form the glass supply passage 8 (glass supply passage forming step). Further, the homogenization tank 3, the condition adjusting tank 4, etc. are connected to the glass supply path 8. After that, the forming furnace 5 is connected to the end of the glass supply path 8 (step of connecting the forming furnace 5). At this time, as shown in FIG. 4, since a slight gap is created between the glass supply passage 8 and the forming furnace 5, it is necessary to move the forming furnace 5 on the support 9 toward the glass supply passage 8. is there. Specifically, the forming furnace 5 is moved, the pipe provided at the end of the forming furnace 5 is aligned with the end of the glass supply path 8 (the lower pipe of the condition adjusting tank 4), and these are connected. (See Figure 5).

When the forming furnace 5 is connected to the glass supply path 8, the annealing furnace 7 is positioned with respect to the forming furnace 5 (positioning step of the annealing furnace 7). In the positioning step of the annealing furnace 7, the annealing furnace 7 is positioned with respect to the forming furnace 5 to position the annealing furnace 7 in the width direction and the plate thickness direction of the plate glass GR formed by the forming furnace 5. As shown in FIG. 5, a device (hereinafter referred to as “positioning device”) 18 for positioning the annealing furnace 7 is attached to the molded body 5a.

In the present embodiment, the positioning device 18 is configured by a laser irradiation device capable of emitting laser light, but is not limited to this, and may be configured by a plumb bob or other positioning tool. The positioning device 18 is configured to be detachable from the molded body 5a. As shown in FIG. 5, the positioning device 18 is arranged in the center of the molded body 5a in the width direction when viewed from the front.

The annealing furnace 7 is provided with a positioning marker 19. The marker 19 is configured to be attachable to and detachable from the slow cooling furnace 7, but is not limited to this. In the positioning step of the slow cooling furnace 7, the laser beam L is emitted vertically downward from the positioning device 18 provided in the molded body 5a, and the slow cooling furnace 7 is moved so that the marker 19 matches the laser beam L (see FIG. 6). ). When the annealing furnace 7 is arranged at a predetermined position, the lock mechanism 12 fixes the wheels 11 of the first support base 10. This completes the positioning of the annealing furnace 7 in the width direction of the forming furnace 5, that is, in the width direction of the sheet glass GR.

Similarly, as shown in FIG. 7, the positioning device 18 is attached so as to coincide with the lower end portion 5e of the molded body 5a in a side view. The slow cooling furnace 7 is moved so that the marker 19 provided on the side surface of the slow cooling furnace 7 matches the laser beam L emitted vertically downward from the positioning device 18 (see FIG. 8 ). When the laser light L and the marker 19 match, the lock mechanism 12 fixes the wheel 11 of the first support 10. This completes the positioning of the slow cooling furnace 7 in the thickness direction of the forming furnace 5, that is, the thickness direction of the sheet glass GR.

The positioning of the slow cooling furnace 7 described above may be performed using a plurality of positioning devices 18, or may be performed by a single positioning device 18. When the positioning of the annealing furnace 7 is completed, the positioning device 18 is removed from the molded body 5a (see FIG. 9).

When the positioning of the slow cooling furnace 7 is completed, the roller units 6a and 6b are positioned next (positioning process of the roller units 6a and 6b). In this case, as shown in FIG. 9, the roller units 6a and 6b are moved to approach the annealing furnace 7. At this time, the roller device 13 is in the standby position and is accommodated in the frame 14.

Further, the frames 14 of the roller units 6a and 6b are adjacent to the annealing furnace 7, and the wheels 16 of the second support 15 are fixed by the lock mechanism 17. After that, as shown in FIG. 10, the roller device 13 at the standby position is changed to the use position, and the roller 13 a is inserted into the annealing furnace 7. With the above, the positioning process of the slow cooling furnace 7 is completed.

After that, the forming furnace 5 and the slow cooling furnace 7 are heated (preheated). This heating is performed by a heater provided in the forming furnace 5 and a heater provided in the slow cooling furnace 7. Each heater continuously heats the inside of the forming furnace 5 and the inside of the slow cooling furnace 7 even during the forming of the sheet glass GR. When the inside of the forming furnace 5 reaches the temperature and a predetermined temperature gradient is formed in the slow cooling furnace 7, the forming of the sheet glass GR by the sheet glass manufacturing apparatus (forming furnace 5) is started.

According to the plate glass manufacturing apparatus according to the present embodiment described above, the roller units 6a, 6b and the slow cooling furnace 7 are configured to be repositionable with respect to the installation floor S, so that the forming furnace 5 is provided in the preheated glass supply path 8. After the connection, the roller units 6a and 6b and the annealing furnace 7 can be easily positioned with respect to the forming furnace 5. As a result, the plate glass manufacturing apparatus according to the present embodiment can efficiently perform the preparatory work before forming the plate glass.

Further, according to the above-described sheet glass manufacturing method of the present embodiment, the preheating step of the glass supply passage 8 is performed in a state of being decomposed into the glass supply pipe 8a, so that the glass resulting from expansion of the glass supply pipe 8a due to heating It is possible to reliably prevent damage to the supply pipe 8a. Further, as described above, since the preparatory step before the forming step of the plate glass GR can be efficiently performed, the plate glass GR can be efficiently produced by this production method.

In addition, in the present embodiment, by supporting the roller units 6a and 6b by the second support base 15, the roller units 6a and 6b can be easily detached from the annealing furnace 7, so that the maintenance work of the roller device 13 is facilitated. Can be done.

FIG. 11 shows a second embodiment of the plate glass manufacturing apparatus. In this embodiment, the configurations of the annealing furnace 7 and the roller units 6a and 6b are different from those in the first embodiment. In the above-described first embodiment, the annealing furnace 7 and the roller units 6a and 6b are supported by separate support bases (first support base 10 and second support base 15), but the flat glass manufacturing apparatus according to the present embodiment In the above, the slow cooling furnace 7 and the roller units 6a and 6b are integrally supported by the single support base 20. As a result, the annealing furnace 7 and the roller units 6a and 6b can be efficiently positioned with respect to the forming furnace 5.

It should be noted that the present invention is not limited to the configurations of the above-described embodiments, and is not limited to the above-described operational effects. The present invention can be variously modified without departing from the scope of the present invention.

In the above embodiment, an example in which the positioning device 18 is attached to the molded body 5a to position the annealing furnace 7 is shown, but the present invention is not limited to this. The positioning device 18 may be mounted on the annealing furnace 7 to perform the positioning, or the positioning device 18 may be installed on the installation floor S to position the annealing furnace 7. In this case, the molded body 5a may be provided with the marker 19.

5 Forming Furnace 6a Roller Unit 6b Roller Unit 7 Annealing Furnace 8 Glass Supply Channel 8a Glass Supply Pipe 10 First Support 11 Wheel 12 Lock Mechanism 13a Roller 14 Frame 15 Second Support 16 Wheel 17 Lock Mechanism 18 Positioning Device 20 Support S Installation floor GM Molten glass GR Flat glass

Claims (8)

A glass supply path formed by connecting a plurality of glass supply pipes for transferring molten glass, a forming furnace for forming the molten glass into plate glass, and an annealing furnace having a roller for transferring the plate glass and installed on the installation floor, A plate glass manufacturing apparatus comprising:
The flat glass manufacturing apparatus is characterized in that the annealing furnace and the roller are configured so that their positions can be changed with respect to the installation floor. The roller is a cantilever roller for individually sandwiching each end portion in the width direction of the plate glass, and is configured as a part of a roller unit by being vertically supported in a plurality of stages and supported by a frame. The plate glass manufacturing apparatus according to claim 1. The plate glass manufacturing apparatus according to claim 2, further comprising a support base that supports the annealing furnace and the roller unit such that their positions can be changed with respect to the installation floor. The support base includes a first support base that supports the annealing furnace in a position changeable with respect to the installation floor, and a second support base that supports the roller unit in a position changeable with respect to the installation floor. The plate glass manufacturing apparatus according to claim 3. The plate glass manufacturing apparatus according to claim 3, wherein the support base includes wheels that can roll on the installation floor and a lock mechanism that locks the wheels. The plate glass manufacturing apparatus according to claim 3, wherein the support base is configured to be capable of changing positions of the annealing furnace and the roller unit along a width direction or a plate thickness direction of the plate glass. The plate glass manufacturing apparatus according to claim 1, further comprising a positioning device that positions the annealing furnace with respect to the forming furnace. A method for producing the sheet glass by the sheet glass production apparatus according to any one of claims 1 to 7,
Heating the plurality of glass supply pipes in a separated state,
Connecting the heated glass supply pipe to configure the glass supply path,
After configuring the glass supply path, connecting the forming furnace to the glass supply path,
Positioning the slow cooling furnace and the roller with respect to the forming furnace after the connection,
While supplying the molten glass to the forming furnace by the glass supply path, a forming step of forming the plate glass by the forming furnace,
A plate glass manufacturing method, comprising:

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