JP2022053621A - Method and device for manufacturing glass sheet - Google Patents

Abstract

To measure a sheet thickness of a lug in a glass stock sheet including a thick lug in manufacturing a glass sheet.SOLUTION: A method for manufacturing a glass sheet includes a first measurement step P2 of measuring a sheet thickness of a lug Gx in a glass stock sheet G1 including an effective part Gy and the lug Gx having a thickness thicker than the effective part Gy. In the first measurement step P2, a sheet thickness of the lug Gx is measured by a first measuring apparatus 3 (infrared thickness gage) that is an absorption-system measuring apparatus.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a method for manufacturing a glass plate and a manufacturing apparatus.

As is well known, a glass plate is used for a display typified by a liquid crystal display, an organic EL display, or the like.

In the glass plate manufacturing process, first, a glass ribbon is continuously formed from molten glass by a downdraw method (for example, an overflow downdraw method) or a float method. Next, the glass ribbon is cut along the width direction for each predetermined length. As a result, a glass original plate having thick ears at both ends in the width direction is cut out from the glass ribbon. Next, the selvages at both ends are separated from the original glass plate to obtain a glass plate from the original glass plate. After that, the glass plate is inspected.

An example of the inspection is the measurement of the plate thickness as disclosed in Patent Document 1. In the form of measurement disclosed in the same document, the measurement is performed while the glass plate is suspended and supported while being conveyed. Then, for measuring the plate thickness, the first CCD camera that detects the change in the height of the lower surface (the end surface located at the lower end) of the glass plate, the second CCD camera that captures the image of the lower surface, and the height of the lower surface. An elevating means for elevating and lowering the second CCD camera according to a change, a control unit for processing an image on the lower surface to obtain a plate thickness, and the like are used.

Japanese Unexamined Patent Publication No. 2002-228422

By the way, for the purpose of quality control of the glass plate, it may be necessary to grasp the plate thickness at the selvage portion of the glass original plate. However, in the form disclosed in Patent Document 1, since it is not assumed that the plate thickness of the selvage is measured, it was expected to establish a means for realizing such a measurement. ..

In view of the above circumstances, the technical problem to be solved is to enable the measurement of the plate thickness in the selvage portion of the glass original plate having the thick selvage portion when manufacturing the glass plate.

The method for manufacturing a glass plate for solving the above problems is a first measurement step of measuring the plate thickness in the selvage portion of a glass original plate having an effective portion and an ear portion thicker than the effective portion. The first measuring step is characterized in that the plate thickness in the selvage portion is measured by an absorption type measuring instrument.

In this method, an absorption type measuring instrument is used to execute the first measurement step. Since the absorption type measuring instrument has a wide range of measurable plate thickness, it is possible to measure the plate thickness in the thick selvage portion of the glass original plate without any problem.

In the above method, when the original glass plate has ears at both ends with an effective portion in between and the direction connecting the ears at both ends is the width direction, in the first measurement step, the glass is formed along the width direction. It is preferable to obtain the plate thickness distribution of the glass original plate by measuring the plate thickness from one end to the other end of the original plate, and to obtain the length of the glass original plate in the width direction based on the plate thickness distribution of the glass original plate. ..

By doing so, it is preferable to control the quality of the glass plate obtained from the glass original plate by acquiring the length of the glass original plate in the width direction (hereinafter referred to as the original plate width) based on the plate thickness distribution of the glass original plate. Can be done. For example, with the aim of preventing the quality of the glass plate from fluctuating as the width of the original plate increases or decreases, management is performed to make the original plate width of these glass original plates the same for a large number of glass original plates cut out from the glass ribbon. It will be easier to do.

In the above method, a first transport step of suspending and supporting the glass original plate in the width direction is provided, and while executing the first transport step, an absorption type measuring instrument arranged in the transport path of the glass original plate is used. It is preferable to carry out one measurement step and measure the plate thickness at the upper part of the glass original plate.

By doing so, the plate thickness is measured in the upper part of the glass original plate, that is, in the vicinity of the suspended and supported portion. Therefore, even if the glass original plate during transportation is shaken due to the execution of the first transfer step, the part where the amplitude of the shaking is small is measured, so that the influence of the shaking on the measurement result is as small as possible. It becomes possible to do. Therefore, the thickness distribution of the original glass plate can be accurately obtained.

In the above method, the ears are divided from the original glass plate to obtain a glass plate as an effective part from the original glass plate, and the glass plate is targeted by a spectral interference type measuring instrument along the width direction. It is preferable to include a second measurement step of obtaining a plate thickness distribution of the glass plate by measuring the plate thickness from one end to the other end of the glass plate.

By doing so, in executing the second measurement step of obtaining the thickness distribution of the glass plate, by using a spectroscopic interference type measuring instrument capable of measuring with higher resolution than the absorption method, a fine glass plate can be obtained. The plate thickness distribution can be obtained.

In the above method, it is preferable to obtain the length of the glass plate in the width direction based on the thickness distribution of the glass plate.

By doing so, the quality control of the glass plate can be more preferably performed by acquiring the length of the glass plate in the width direction based on the plate thickness distribution of the glass plate.

The above method includes a second transport process in which the glass plate is suspended and supported in the width direction, and a spectral interference type measuring instrument arranged in the transport path of the glass plate while executing the second transport step is used. It is preferable to carry out the second measurement step and measure the plate thickness at the upper part of the glass plate.

By doing so, even if the glass plate being conveyed is shaken due to the execution of the second transfer step, the influence of the shaking on the measurement result can be minimized. Therefore, it is possible to obtain the plate thickness distribution of the glass plate more accurately.

Further, the glass plate manufacturing apparatus for solving the above-mentioned problems is a measuring instrument for measuring the plate thickness in the selvage portion of a glass original plate having an effective portion and an ear portion thicker than the effective portion. The device is characterized in that the measuring instrument is an absorption type measuring instrument.

According to this apparatus, it is possible to similarly obtain the above-mentioned actions and effects of the above-mentioned method for manufacturing a glass plate.

According to the method and apparatus for manufacturing a glass plate according to the present disclosure, when manufacturing a glass plate, it is possible to measure the plate thickness at the selvage portion of a glass original plate having a thick selvage portion.

It is a top view which shows the manufacturing method and manufacturing apparatus of a glass plate. It is a front view which shows the manufacturing method and manufacturing apparatus of a glass plate. It is a figure which shows the plate thickness distribution of a glass original plate. It is a figure which shows the plate thickness distribution of a glass plate.

Hereinafter, the method for manufacturing the glass plate and the manufacturing apparatus according to the embodiment will be described with reference to the attached drawings. The X, Y, and Z directions shown in FIGS. 1 and 2 are orthogonal to each other. The X direction is equal to the width direction of the glass original plate G1 and the glass plate G2, and the Y direction is equal to the thickness direction of the glass original plate G1 and the glass plate G2. Further, the Z direction is the vertical direction.

<Glass plate manufacturing equipment>
First, the glass plate manufacturing apparatus 1 (hereinafter, simply referred to as manufacturing apparatus 1) will be described.

The manufacturing apparatus 1 shown in FIGS. 1 and 2 includes a plurality of transport devices 2 for transporting the glass original plate G1 or the glass plate G2 in a vertical position in a suspended and supported state in the width direction (X direction), and a width. The first measuring device 3 for measuring the plate thickness from one end G1a to the other end G1b of the glass original plate G1 along the direction, and the ear portion Gx from the glass original plate G1 are separated from the glass original plate G1 to the effective portion Gy. The glass plate G2 is provided with a cutting device (not shown) for obtaining the glass plate G2, and a second measuring device 4 for measuring the plate thickness from one end G2a to the other end G2b of the glass plate G2 along the width direction. ing.

Here, the glass original plate G1 and the glass plate G2 will be described.

The glass original plate G1 is formed from a glass ribbon by cutting a glass ribbon continuously formed from molten glass by a downdraw method (for example, an overflow downdraw method) or a float method along a predetermined length in a width direction. It is cut out. The glass original plate G1 has an effective portion Gy that later becomes a glass plate G2 and an ear portion Gx that is thicker than the effective portion Gy, and the selvage portions Gx are formed at both ends in the width direction with the effective portion Gy sandwiched between them. Has been done. The glass plate G2 is an effective portion Gy after being separated from the selvage portion Gx by the cutting device. The thickness t1 of the glass plate G2 (effective portion Gy) is, for example, 30 μm to 1100 μm, and the thickness t2 of the selvage portion Gx is 1200 μm to 3000 μm as an example. The thickness ratio (t2 / t1) is 3 to 8 as an example.

The transport path (the right side is the upstream side and the left side is the downstream side in FIGS. 1 and 2) of the glass original plate G1 (glass plate G2) extending in the X direction is divided into a plurality of sections, one for each section. The transport device 2 is arranged. That is, the manufacturing apparatus 1 includes the same number of transport devices 2 as the number of sections. Each transport device 2 can reciprocate along the X direction and can move between the upstream end and the downstream end within the section to which the transport device 2 belongs.

Each transfer device 2 receives the glass original plate G1 or the glass plate G2 at the upstream end of the section to which the transfer device 2 belongs. Each transport device 2 transports the received glass original plate G1 or glass plate G2 to the downstream end of the section, and then delivers the glass original plate G1 or glass plate G2 to the transport device 2 belonging to the adjacent section. After delivering the glass original plate G1 or the glass plate G2, each transport device 2 returns to the upstream end of the section to which the next glass original plate G1 or the glass plate G2 belongs to receive the next glass original plate G1 or the glass plate G2.

In the present manufacturing apparatus 1, the plurality of glass original plates G1 transferred from the upstream process are sequentially carried into the cutting apparatus by the plurality of transport devices 2, and the plurality of glass plates cut out from the glass original plates G1 are sequentially carried. G2 is sequentially carried out from the cutting device and transferred to the downstream process.

Each transport device 2 includes a chuck 5 as a support member capable of supporting (grasping) the upper side portion of the glass original plate G1 or the glass plate G2. The chuck 5 suspends the original glass plate G1 or the glass plate G2. The chuck 5 supports and releases the support of the upper side portion by opening and closing the claws provided on the chuck 5 when receiving and delivering the glass original plate G1 or the glass plate G2 described above.

Here, as a modification of the present embodiment, a single transport device in which the manufacturing apparatus 1 can reciprocate along the transport path of the glass original plate G1 (glass plate G2) instead of the plurality of transport devices 2 is used. You may be prepared. That is, the glass original plate G1 and the glass plate G2 may be conveyed by a single transfer device. Further, as another modification of the present embodiment, the transport device 2 may be provided with a suction pad capable of sucking the upper side portion of the glass original plate G1 or the glass plate G2 as a support member instead of the chuck 5.

The first measuring device 3 is arranged in the transport path of the glass original plate G1. The first measuring device 3 is an infrared thickness gauge as an absorption type measuring device. The first measuring device 3 includes a floodlight 6 and a light receiver 7. The floodlight 6 and the light receiver 7 face each other with a pass line through which the glass original plate G1 passes during transportation. Both the floodlight 6 and the light receiver 7 are arranged at the same height position in the vertical direction (Z direction). The floodlight 6 can emit infrared rays 8 perpendicularly to the surface G1s of the glass original plate G1.

When measuring the plate thickness of the glass original plate G1 by the first measuring device 3, the glass original plate G1 is transmitted through the infrared rays 8 emitted by the floodlight 6 (transmitted from the front surface G1s side to the back surface G1t side) to reach the light receiver 7. .. At this time, the attenuated infrared ray 8 is detected as an electric signal and converted into a current value to measure the plate thickness of the glass original plate G1.

The height position (position in the Z direction) of the first measuring device 3 is adjusted so that the plate thickness is measured at the upper portion of the glass original plate G1. This is for the purpose of minimizing the influence of the shaking (shaking along the Y direction) generated on the glass original plate G1 with the transportation of the glass original plate G1 on the measurement result. The height position of the first measuring device 3 will be described in more detail. In the upper part of the glass original plate G1, below the portion supported (grasped) by the chuck 5, and to support (grip) the chuck 5. The height position of the first measuring device 3 is adjusted so that the plate thickness is measured at a place where the glass original plate G1 is not deformed. As an example of the height position of the first measuring device 3 (plate thickness measuring point), it is a position separated from the upper side (upper edge) of the glass original plate G1 by a distance of 100 mm to 300 mm downward.

The first measuring device 3 continuously measures the plate thickness from one end G1a to the other end G1b of the glass original plate G1 by allowing the glass original plate G1 to cross between the floodlight 6 and the light receiver 7 (for example,). Measured at a pitch of 1 mm). As a result, the plate thickness measurement proceeds from the left side to the right side of the figure along the line 9 shown by the alternate long and short dash line in FIG. Here, the range of the plate thickness that can be measured by the first measuring device 3 is, for example, more than 0 μm to 3200 μm. The resolution of the first measuring device 3 is, for example, about 2 μm.

Here, as a modification of the present embodiment, an absorption type measuring device other than the infrared thickness gauge may be used as the first measuring device 3.

The cutting device (not shown) is arranged on the transport path of the glass original plate G1 (glass plate G2) on the downstream side of the first measuring device 3 and on the upstream side of the second measuring device 4. .. As the cutting device, any device can be adopted as long as the selvage portion Gx can be separated from the glass original plate G1. As an example, a mechanism for forming a scribe line along the boundary line 10 between the selvage portion Gx and the effective portion Gy with respect to the glass original plate G1 in a suspended and supported state, and a glass original plate G1 along the scribe line. It is possible to adopt a device equipped with a mechanism for folding and cutting. In addition, a device that cuts the glass original plate G1 along the boundary line 10 by laser cutting or laser cutting may be used as a cutting device.

The second measuring device 4 is arranged in the transport path of the glass plate G2. The second measuring device 4 includes a spectroscopic interferometer 11 as a spectroscopic interference type measuring instrument and a mirror disk 12. The spectroscopic interferometer 11 and the mirror plate 12 face each other with a pass line through which the glass plate G2 passes during transportation. Both the spectroscopic interferometer 11 and the mirror plate 12 are arranged at the same height position in the vertical direction (Z direction). The spectroscopic interferometer 11 can emit the laser beam 13 perpendicularly to the surface G2s of the glass plate G2 and can receive the reflected light. The end plate 12 has a flat reflecting surface 12a, and the reflecting surface 12a is arranged so as to be parallel to the front surface G2s and the back surface G2t of the glass plate G2.

When measuring the plate thickness of the glass plate G2 by the second measuring device 4, a part of the laser light 13 emitted by the spectroscopic interferometer 11 reflected by the front surface G2s of the glass plate G2 and the light reflected by the back surface G2t. A part of the light is received by the spectroscopic interferometer 11 together. Further, of the laser light 13 emitted by the spectroscopic interferometer 11, the glass plate G2 is transmitted (transmitted from the front surface G2s side to the back surface G2t side) and reflected by the reflecting surface 12a of the mirror plate 12, and then the glass plate G2 is again pressed. A part of the transmitted light (transmitted from the back surface G2t side to the front surface G2s side) is received by the spectral interferometer 11. The thickness of the glass plate G2 is measured based on the interference of light at this time.

The second measuring device 4 (spectral interferometer 11 and mirror board 12) has a height position (Z direction) so that the plate thickness is measured at the upper portion of the glass plate G2 for the same reason as the first measuring device 3. Position in) is adjusted. Specifically, the thickness of the upper portion of the glass plate G2 is lower than the portion supported (grasped) by the chuck 5 and where the glass plate G2 is not deformed due to the support (grasping) of the chuck 5. The height position of the second measuring device 4 is adjusted so as to be measured. In the present embodiment, the first measuring device 3 and the second measuring device 4 are at the same height position. However, this is not the case, and both devices 3 and 4 may be at different height positions.

The second measuring device 4 continuously measures the plate thickness from one end G2a to the other end G2b of the glass plate G2 by allowing the glass plate G2 to cross between the spectroscopic interferometer 11 and the mirror plate 12. (For example, measured at a pitch of 1 mm). As a result, the plate thickness measurement proceeds from the left side to the right side of the figure along the line 14 shown by the alternate long and short dash line in FIG. Here, the range of the plate thickness that can be measured by the second measuring device 4 is, for example, 0.05 μm to 800 μm. Further, the resolution of the second measuring device 4 is 0.01 μm or less as an example. As described above, in comparison with the first measuring device 3, the second measuring device 4 has a narrow range of measurable plate thickness, but has a high measurement resolution.

Here, as a modification of the present embodiment, the mirror disk 12 may be omitted from the second measuring device 4. In this case, of the laser light 13 emitted by the spectral interferometer 11, a part of the light reflected by the front surface G2s of the glass plate G2 and a part of the light reflected by the back surface G2t are both received by the spectral interferometer 11. Let me. The thickness of the glass plate G2 is measured based on the interference of light at this time.

<Manufacturing method of glass plate>
Hereinafter, a method for manufacturing a glass plate using the above-mentioned manufacturing apparatus 1 (hereinafter, simply referred to as a manufacturing method) will be described.

In this manufacturing method, as shown in FIGS. 1 and 2, the first transport step P1 and the first measuring device 3 for transporting the glass original plate G1 cut out from the glass ribbon (not shown) are conveyed by using the transport device 2. The first measurement step P2 for obtaining the plate thickness distribution of the glass original plate G1 (see FIG. 3) by measuring the plate thickness of the glass original plate G1 and the first measurement step P2 using a cutting device were performed. Using the dividing step P3 for dividing the ear portion Gx from the glass original plate G1 to obtain the glass plate G2, the second transporting step P4 for transporting the glass plate G2 using the transport device 2, and the second measuring device 4. A second measurement step P5 for obtaining a plate thickness distribution (see FIG. 4) of the glass plate G2 by measuring the plate thickness of the glass plate G2 is provided.

The first measurement step P2 is performed while executing the first transfer step P1. When the first measurement step P2 is completed, the plate thickness distribution of the glass original plate G1 as shown in FIG. 3 is obtained. The plate thickness distribution of the glass original plate G1 includes the plate thickness distribution of the selvage portion Gx and the plate thickness distribution of the effective portion Gy. Then, the length L1 of the glass original plate G1 in the width direction can be obtained based on the plate thickness distribution of the glass original plate G1. Further, the width (length along the width direction) of the selvage portion Gx can be grasped from the plate thickness distribution of the glass original plate G1.

The dividing step P3 is performed under a state in which the transfer by the transfer device 2 (conveyance of the glass original plate G1) is temporarily stopped. When the selvage portion Gx is separated from the glass original plate G1 to obtain the glass plate G2, the transfer by the transfer device 2 (transportation of the glass plate G2) is restarted.

The second measurement step P5 is performed while executing the second transfer step P4. When the second measurement step P5 is completed, the plate thickness distribution of the glass plate G2 as shown in FIG. 4 is obtained. The plate thickness distribution of the glass plate G2 does not include the plate thickness distribution of the selvage portion Gx, but includes only the plate thickness distribution of the glass plate G2 (effective portion Gy). The plate thickness distribution of the glass plate G2 shown in FIG. 4 corresponds to the plate thickness distribution of the portion surrounded by the square A in FIG. 3, but is finer than the plate thickness distribution of FIG. Then, the length L2 of the glass plate G2 in the width direction can be obtained based on the plate thickness distribution of the glass plate G2.

The glass plate G2 after the second measurement step P5 undergoes an inspection other than the measurement of the plate thickness, and then is packed on a pallet, for example, for shipping, storage, or the like. As described above, the glass plate G2 is manufactured.

Hereinafter, the main actions / effects of the above-mentioned manufacturing apparatus 1 and the manufacturing method will be described.

In the above-mentioned manufacturing apparatus 1 and manufacturing method, in measuring the thickness of the selvage portion Gx of the glass original plate G1, the first measuring apparatus 3 (infrared thickness gauge) which is an absorption type measuring instrument is used. Since the absorption type measuring instrument has a wide range of measurable plate thickness, it is possible to measure the plate thickness of the thick selvage portion Gx of the glass original plate G1 without any problem.

1 Glass plate manufacturing equipment 3 First measuring equipment (infrared thickness gauge)
11 Spectral interferometer G1 glass original plate G1a one end of glass original plate G1b other end of glass original plate G2 glass plate G2a one end of glass plate G2b other end of glass plate Gx ear part Gy effective part L1 length of glass original plate Length P1 1st transfer process P2 1st measurement process P3 Dividing process P4 2nd transfer process P5 2nd measurement process

Claims (7)

For a glass original plate having an effective portion and an ear portion thicker than the effective portion.
It is a method of manufacturing a glass plate provided with a first measurement step of measuring the plate thickness in the selvage portion.
The first measuring step is a method for manufacturing a glass plate, characterized in that the plate thickness in the selvage portion is measured by an absorption type measuring instrument. The glass original plate has the ears at both ends with the effective portion in between.
When the direction connecting the ears at both ends is the width direction,
In the first measurement step, the plate thickness distribution of the glass original plate is obtained by measuring the plate thickness from one end to the other end of the glass original plate along the width direction.
The method for manufacturing a glass plate according to claim 1, wherein the length of the glass original plate in the width direction is obtained based on the plate thickness distribution of the glass original plate. A first transport step of transporting the original glass plate in the width direction while suspending and supporting the original glass plate is provided.
While executing the first transfer step, the first measurement step is executed by the absorption type measuring instrument arranged in the transfer path of the glass original plate, and the plate thickness is measured at the upper part of the glass original plate. The method for manufacturing a glass plate according to claim 2. A dividing step of obtaining a glass plate having the effective portion from the glass original plate by dividing the selvage portion from the glass original plate.
The second is to obtain the plate thickness distribution of the glass plate by measuring the plate thickness of the glass plate from one end to the other end along the width direction with a spectroscopic interference type measuring device. Measurement process and
The method for manufacturing a glass plate according to claim 2 or 3, wherein the glass plate is provided. The method for manufacturing a glass plate according to claim 4, wherein the length of the glass plate in the width direction is obtained based on the thickness distribution of the glass plate. The second transfer step of transporting the glass plate in the width direction while suspending and supporting the glass plate is provided.
While executing the second transfer step, the second measurement step is executed by the spectroscopic interference type measuring instrument arranged in the transfer path of the glass plate, and the plate thickness is measured at the upper part of the glass plate. The method for manufacturing a glass plate according to claim 4 or 5. For a glass original plate having an effective portion and an ear portion thicker than the effective portion.
It is a glass plate manufacturing apparatus provided with a measuring instrument for measuring the plate thickness in the selvage portion.
A glass plate manufacturing apparatus, wherein the measuring instrument is an absorption type measuring instrument.

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