Apparatus for manufacturing glass sheet and method for manufacturing glass sheet

Abstract

Provided is a glass sheet manufacturing apparatus and a glass sheet manufacturing method that enable accurate measurement of the moving speed of a glass ribbon without being affected by wrinkles that occur with the formation of a score line. A glass sheet manufacturing apparatus (1) includes a forming device (2) that forms a glass ribbon (R), a conveyance device (3) that conveys the glass ribbon (R) in a downward direction, a speed measurement device (4) that measures the moving speed of the glass ribbon (R) being conveyed in the downward direction, and a cutting device (5) that cuts out a single glass sheet (Gp) from the glass ribbon (R). The cutting device (5) includes a scoring device (15) that forms a score line (S) from the one end (R1) side of the glass ribbon (R) toward the other end (R2) side. The speed measurement device (4) measures the moving speed of a region of the glass ribbon (R) on the one end (R1) side of the center in the width direction.

Description

Technical Field

[0001] This invention relates to a manufacturing technology for a glass plate having a structure for measuring the moving speed of a glass ribbon. Background Technology

[0002] In the field of glass sheet manufacturing, it is well known that a method is used to form glass ribbons using a pull-down process and to cut individual glass sheets from the formed glass ribbons.

[0003] In this method, in order to reduce the unevenness of the glass strip thickness and strain, it is necessary to accurately measure the moving speed of the glass strip.

[0004] As a method for measuring the moving speed of the glass belt, for example, Patent Document 1 discloses a method for calculating the moving speed of the glass belt based on the rotational speed of the traction roller that pulls the glass belt downward.

[0005] In this case, it is common practice to have multiple traction rollers positioned to clamp the two ends of the glass strip in the width direction orthogonal to the direction of movement. In this document, it can be understood that the movement speed of the glass strip is calculated based on the rotational speed of one of the traction rollers (e.g., one).

[0006] Furthermore, this document also discloses a method for cutting single-sheet glass plates from a pre-formed glass ribbon. When cutting the glass plates, if the method described in this document... Figure 2 as well as Figure 3 Once mastered, use a scribing tool (scrubbing wheel (56)) to form scribing lines (scrubbing lines (60)) on the glass strip (26). Afterwards, if it is possible to follow the instructions in this document... Figure 6 D and Figure 6 As E et al. have demonstrated, bending stress is applied to the area where the scribed lines are formed, causing the glass ribbon to break.

[0007] In this case, the scribing lines extend along the width of the glass strip. Therefore, when forming the scribing lines, the scribing tool travels along the width of the glass strip.

[0008] Existing technical documents

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Application Publication No. 2013-043828 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] However, as the scribing tool travels along the width of the glass ribbon, wrinkles may form within the ribbon. Specifically, wrinkles may occur in the latter half of the period from the beginning to the end of the formation of the scribing line. Therefore, wrinkles may form in the region on the terminal side of the scribing line within the glass ribbon.

[0013] In this case, in Patent Document 1, when a portion of the traction roller used in measuring the moving speed of the glass belt is positioned at the end of the end of the scribed line in the glass belt, the moving speed of the glass belt is difficult to measure accurately due to the aforementioned wrinkles.

[0014] Based on the above viewpoints, the objective of this invention is to accurately measure the moving speed of a glass ribbon, making it less susceptible to the influence of wrinkles that accompany the formation of the scribe lines.

[0015] Solution for solving the problem

[0016] (1) The first aspect of the present invention, made to solve the above-mentioned problems, is a glass plate manufacturing apparatus comprising: a forming body that forms a glass strip from molten glass; a conveying device that conveys the glass strip in a downward direction; a speed measuring device that measures the moving speed of the glass strip conveyed in the downward direction by the conveying device; and a cutting device that cuts a single sheet of glass from the glass strip. The glass plate manufacturing apparatus is characterized in that the cutting device comprises: a scribing device that forms a scribing line extending along the width direction of the glass strip from one end side of the glass strip in a width direction orthogonal to the conveying direction toward the other end side; and a breaking device that breaks the glass strip at the location where the scribing line is formed to obtain a single sheet of glass. The speed measuring device measures the moving speed of a region of the glass strip that is closer to one end side than the center in the width direction.

[0017] In this structure, the scribing line is formed by the scribing device from one end of the glass ribbon in the width direction toward the other end, thus the other end of the glass ribbon becomes the terminal side of the scribing line in the glass ribbon. In this case, wrinkles are easily formed in the region at the terminal side of the scribing line in the glass ribbon during the formation of the scribing line. Therefore, in this structure, the speed measuring device measures the moving speed of the glass ribbon in the region other than the terminal side of the scribing line, that is, the region of the glass ribbon closer to one end side than the center in the width direction. As a result, the speed measuring device can measure the moving speed of the glass ribbon in a region where wrinkles are less likely to occur, and can perform accurate measurement of the moving speed.

[0018] (2) In the structure described in (1) above, the forming apparatus may also include: a forming body that forms a glass ribbon from molten glass; and an edge roller that clamps both ends of the glass ribbon descending from the forming body in the width direction and conveys it downwards, and a speed measuring device measures the moving speed of the region of the glass ribbon that is closer to the center side in the width direction than the contact portion that contacts the edge roller. In this case, the "contact portion" mentioned above strictly means the trace of the contact portion (hereinafter the same).

[0019] Here, unevenness forms at the contact portion of the glass belt that contacts the edge roller. Therefore, when using a contact-type speed measuring device (such as the measuring roller described later), the movement speed of the glass belt cannot be accurately measured due to the unevenness. Furthermore, the contact portion of the glass belt that contacts the edge roller has significant residual stress, so there is a possibility that this contact portion may break and fall off midway through the downward transport of the glass belt. Therefore, even when using a non-contact speed measuring device (such as the non-contact sensor described later), the movement speed of the glass belt cannot be accurately measured. According to this structure, regardless of whether a contact or non-contact speed measuring device is used, the movement speed is measured in the area of ​​the glass belt other than the contact portion that contacts the edge roller, thus enabling accurate measurement of the movement speed.

[0020] (3) In the structure of (1) or (2) above, the glass strip may have ears at both ends in the width direction with a thickness greater than that of the central part in the width direction, and the speed measuring device measures the moving speed of the region of the glass strip that is closer to the central side in the width direction than the ears.

[0021] Here, the lugs at both ends of the glass strip in the width direction have the aforementioned irregularities. Therefore, when using a contact-type speed measuring device, the movement speed of the glass strip cannot be accurately measured due to the irregularities. Furthermore, the lugs have significant residual stress, which could cause them to break and fall off midway through the downward transport of the glass strip. Therefore, regardless of whether a contact or non-contact speed measuring device is used, the movement speed of the glass strip cannot be accurately measured. With this structure, the movement speed is measured in the area of ​​the glass strip excluding the lugs, thus enabling accurate measurement of the movement speed regardless of whether a contact or non-contact speed measuring device is used.

[0022] (4) In any of the structures (1) to (3) above, the speed measuring device may also include a measuring roller that rotates in contact with the glass strip and measures the moving speed of the glass strip based on the rotation speed of the measuring roller.

[0023] Here, the glass strip is a continuously formed transparent body, making it difficult to measure the moving speed non-contactly using optical mechanisms or the like. Based on this structure, the measuring roller is brought into contact with the glass strip to measure the moving speed, thus enabling accurate measurement of the moving speed.

[0024] (5) In the structure of (4) above, the measuring roller may also be a free roller. In this case, a free roller means a roller that is not given a rotational driving force (hereinafter the same).

[0025] If the measuring roller is set as a free roller, slippage is less likely to occur between the glass belt and the measuring roller, thus enabling accurate measurement of the glass belt's moving speed.

[0026] (6) In the structure of (4) or (5) above, the glass plate manufacturing apparatus may also include an annealing furnace for annealing the glass strip below the formed body, a conveying device for conveying the glass strip in the annealing furnace, the annealing roller holding a region of the glass strip that is closer to the center side in the width direction than the contact portion that contacts the edge roller, and a speed measuring device measuring the moving speed of the region of the glass strip other than the contact portion that contacts the annealing roller.

[0027] Here, at the contact portion of the glass belt that contacts the annealing roller, glass powder or other particles adhering to the annealing roller may be pressed onto the glass belt. Therefore, tiny cracks may form in the glass belt, potentially reducing its strength at these locations. Consequently, if the structure measures the glass belt's movement speed by having the measuring roller contact this formed area, the glass belt may break. With this structure, the measuring roller contacts an area of ​​the glass belt other than the contact portion with the annealing roller to measure the movement speed, thus enabling accurate measurement of the movement speed without damaging the glass belt.

[0028] (7) In the structure of (6) above, the speed measuring device may also measure the moving speed of the region of the glass belt that is in contact with the annealing roller and is located on the central side in the width direction.

[0029] Here, according to the structure described in (6) above, the moving speed can also be measured by making the contact area between the measuring roller and the contact area between the annealing roller and the edge roller in the glass belt come into contact with each other. However, the thickness of the glass belt is not constant in this contact area. Therefore, if the moving speed is measured by making the contact area between the measuring roller and the annealing roller in the glass belt, as described in this structure, come into contact with the central side of the contact area in the width direction, the moving speed can be measured more accurately.

[0030] (8) In any of the structures (4) to (7) above, the glass plate manufacturing apparatus may also include a cooling chamber below the annealing furnace for cooling the glass strip, a conveying device including a support roller for supporting the glass strip in the cooling chamber, the support roller holding a region of the glass strip that is closer to the center side in the width direction than the contact portion that contacts the edge roller, and a speed measuring device measuring the moving speed of the region of the glass strip other than the contact portion that contacts the support roller.

[0031] Here, at the contact portion of the glass belt that contacts the support roller, glass powder or other particles adhering to the support roller may be pressed onto the glass belt from the support roller. As a result, tiny cracks may form in the glass belt, thus reducing the strength at these cracked areas. Therefore, if the structure is designed to measure the speed of the glass belt by having the measuring roller contact this cracked area, the glass belt may break. With this structure, the measuring roller contacts an area of ​​the glass belt other than the contact portion with the support roller to measure the speed, thus enabling accurate measurement of the speed without damaging the glass belt.

[0032] (9) In the structure of (8) above, the speed measuring device may also measure the moving speed of the region in the glass belt that is closer to the center side in the width direction than the contact part that contacts the support roller.

[0033] Here, according to the structure described in (8) above, the measuring roller can also contact the area between the contact portion of the glass belt that contacts the support roller and the contact portion that contacts the edge roller to measure the moving speed. However, the thickness of the glass belt is not constant in this area. Therefore, if the measuring roller contacts the area of ​​the glass belt that contacts the support roller on the central side in the width direction, as in the structure described here, the moving speed can be measured more accurately.

[0034] (10) In any of the structures (1) to (9) above, the glass strip may have an effective area existing on the central side in the width direction and an ineffective area that is the entire area on the end side in the width direction that is closer to the effective area, and the speed measuring device measures the moving speed of the ineffective area.

[0035] In this way, when using a contact-type speed measuring device, the device contacts the non-effective area of ​​the glass strip, but not the effective area. Therefore, it prevents foreign objects from adhering to the effective area or causing damage to it. This leads to improved quality of the product glass sheet. Here, the effective area refers to the area used as the product glass sheet, and the non-effective area refers to the area discarded as an unnecessary part.

[0036] (11) In any of the structures (4) to (10) above, the speed measuring device may also have an auxiliary roller disposed at a position corresponding to the measuring roller, separated by a glass belt.

[0037] In this way, the glass strip is sandwiched between the measuring roller and the auxiliary roller, so it is not easy for slippage to occur between the glass strip and the measuring roller, and the moving speed of the glass strip can be measured more accurately.

[0038] (12) In the structure of (11) above, the auxiliary roller may also be a drive roller. In this case, the drive roller means a roller that is given a rotational driving force (hereinafter the same).

[0039] Here, if the structure is configured such that the auxiliary roller, which serves as the drive roller, is driven by a motor whose rotational speed can be variably controlled, such as a servo motor, the following effect is achieved: That is, during startup or maintenance of the manufacturing apparatus, the auxiliary roller is used to rotate the measuring roller in a state where the glass belt is not clamped and the measuring roller is in direct contact. Furthermore, if the rotational speed of the auxiliary roller is set to N times, it is possible to confirm whether the measurement result of the measuring roller is erroneous simply by checking whether the rotational speed of the measuring roller is also N times. Therefore, according to this structure, it is possible to check in advance whether the measuring roller is functioning accurately using a simple method.

[0040] (13) In the structure of (12) above, the rotational speed of the auxiliary roller may also be controlled in such a way as to follow the moving speed of the glass belt measured by the measuring roller.

[0041] Here, it is considered that the rotational speed of the auxiliary roller should follow the transport speed of the glass ribbon being transported by the transport device. However, slippage may inevitably occur between the rollers of the transport device and the glass ribbon. Therefore, it is difficult to accurately match the moving speed of the glass ribbon with the rotational speed of the auxiliary roller. According to the structure here, the rotational speed of the auxiliary roller should follow the moving speed measured by the measuring roller, thus enabling a more accurate match between the moving speed of the glass ribbon and the rotational speed of the auxiliary roller.

[0042] (14) In any of the structures (11) to (13) above, the measuring roller may be arranged on one side of the glass belt and the auxiliary roller may be arranged on the other side of the glass belt, and the measuring roller may be subjected to pressure from the auxiliary roller through the glass belt.

[0043] In this way, under the pressing force exerted by the auxiliary roller on the measuring roller, slippage is less likely to occur between the measuring roller and one side of the glass belt.

[0044] (15) In the structure of (14) above, the scribing device may also include: a scribing tool that forms scribing lines on the other side of the glass strip; and a support body that contacts one side of the glass strip and supports the glass strip when the scribing tool forms scribing lines.

[0045] In this way, when forming the scribe lines on the glass strip, the direction in which the scribe tool presses against the support body is consistent with the direction in which the auxiliary roller presses against the measuring roller. As a result, the glass strip is less likely to wobble during the formation of the scribe lines, and the measurement of the glass strip's moving speed by the measuring roller can be performed more accurately.

[0046] (16) In any of the structures (1) to (15) above, a guide roller for holding the glass strip may be provided in the region of the glass strip at the end side of the center in the width direction and at a height position corresponding to the speed measuring device.

[0047] In this way, the swaying of the glass belt can be suppressed by using the guide roller at the appropriate position (the height position corresponding to the speed measuring device), thus enabling further accurate measurement of the moving speed.

[0048] (17) In any of the structures (4) to (16) above, at least the outer periphery of the measuring roller may be formed of heat-resistant rubber.

[0049] This design minimizes slippage between the glass belt and the measuring roller, enabling accurate measurement of the glass belt's movement speed. Furthermore, it is less affected by the temperature of the glass belt (high temperature), thus extending the lifespan of the measuring roller.

[0050] (18) In any of the structures (1) to (17) above, the speed measuring device may be located in the area below the transport device and above the scribing device to measure the moving speed of the glass strip.

[0051] Here, when the speed of the glass ribbon is measured in an area above the conveying device, it is impossible to accurately measure the speed if the glass ribbon deflects between the forming device and the conveying device. Furthermore, when the speed of the glass ribbon is measured in an area below the scribing device, there is a possibility that the speed cannot be accurately measured if the measuring area overlaps with the scribing line, or that the glass ribbon may break at the scribing line in the case of a contact-type speed measuring device. According to this structure, by measuring the speed in the area between the conveying device and the scribing device, the speed can be accurately measured without damaging the glass ribbon.

[0052] (19) In the structure of (18) above, the glass plate manufacturing apparatus may also have a limiting member in the area below the speed measuring device and above the scribing device to limit the swing of the glass strip.

[0053] In this way, the swaying of the glass ribbon caused when the glass plate is broken off from the glass ribbon during the process of forming the scribe lines is not easily transmitted to the position of the speed measuring device, thus enabling accurate measurement of the moving speed.

[0054] (20) In any of the structures (1) to (3) above, the speed measuring device can also measure the moving speed of the glass strip in a non-contact manner.

[0055] In this way, the speed measuring device does not come into contact with the glass strip, thus preventing the glass strip from breaking or being damaged, and avoiding problems caused by slippage with the glass strip, while measuring the moving speed.

[0056] (21) In the structure of (20) above, the speed measuring device may also include multiple sensors arranged below the position where the glass strip is broken by the breaking device and capable of detecting the presence or absence of the glass strip. The multiple sensors are arranged at different positions in the vertical direction. The speed measuring device uses the multiple sensors to detect the time when the lower end face of the glass strip formed by the breaking device is positioned and the vertical distance between each of the multiple sensors, and calculates the moving speed of the glass strip.

[0057] Here, the glass ribbon is a continuously formed transparent body, making it difficult to measure its speed non-contactly using optical mechanisms or similar methods. However, the position of the lower end face (cut-off end face) of the glass ribbon can be easily detected non-contactly using a sensor capable of detecting the presence or absence of the glass ribbon. Therefore, by placing multiple sensors at different positions in the vertical direction, the moving speed of the glass ribbon can be accurately measured using simple calculations of time and distance. It should be noted that sensors capable of detecting the presence or absence of the glass ribbon include laser sensors, ultrasonic sensors, and thermal imagers.

[0058] (22) In any of the structures (1) to (21) above, the cutting device may also move downwards following the moving speed of the glass strip measured by the speed measuring device.

[0059] Here, it is considered that the moving speed of the cutting device should follow the conveying speed of the glass ribbon being transported by the conveying device. However, slippage may inevitably occur between the rollers of the conveying device and the glass ribbon. Therefore, it is difficult to accurately match the moving speed of the glass ribbon with the moving speed of the cutting device. According to the structure here, the moving speed of the cutting device should follow the moving speed measured by the measuring roller, thus enabling a more accurate match between the moving speed of the glass ribbon and the moving speed of the cutting device.

[0060] (23) A second aspect of the present invention, made to solve the above-mentioned problems, is a method for manufacturing a glass sheet, comprising: a forming step, forming a glass strip from molten glass; a transporting step, transporting the glass strip in a downward direction; a speed measuring step, measuring the moving speed of the glass strip during the transporting step; and a cutting step, cutting a single sheet of glass from the glass strip, wherein the method for manufacturing the glass sheet is characterized in that the cutting step comprises: a scribing step, forming a scribing line extending along the width direction of the glass strip from one end side of the glass strip in a width direction orthogonal to the transporting direction toward the other end side; and a breaking step, breaking the glass strip at the location where the scribing line was formed to obtain a single sheet of glass, wherein the moving speed of a region of the glass strip closer to one end side than the center in the width direction is measured in the speed measuring step.

[0061] According to the manufacturing method of the glass plate, the effect is substantially the same as that of the structure described above (1).

[0062] Invention Effects

[0063] According to the present invention, when measuring the moving speed of the glass strip, it is less affected by the wrinkles that accompany the formation of the scribing lines, and the moving speed can be accurately measured. Attached Figure Description

[0064] Figure 1 This is a perspective view showing the overall structure of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0065] Figure 2 According to Figure 1 The longitudinal section side view obtained by cutting along line A-A.

[0066] Figure 3 This is a longitudinal sectional side view used to illustrate the operation of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0067] Figure 4 This is a longitudinal sectional side view used to illustrate the operation of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0068] Figure 5This is a longitudinal sectional side view used to illustrate the operation of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0069] Figure 6 This is a cross-sectional top view illustrating the operation of the main part of the breaking device, a component of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0070] Figure 7 This is a longitudinal sectional side view used to illustrate the operation of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0071] Figure 8 This is a longitudinal sectional side view used to illustrate the operation of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0072] Figure 9 This is a top view showing the structure of the main part of the speed measuring device, a constituent element of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0073] Figure 10 This is a front view obtained by observing the structure of the main parts of the glass plate manufacturing apparatus according to the first embodiment of the present invention from one side (surface side) of the glass strip.

[0074] Figure 11 This is a top view showing the cross-section of a glass strip cut along its width.

[0075] Figure 12 This is a cross-sectional top view for illustrating the operation of the scribing device, a component of the glass plate manufacturing apparatus according to the first embodiment of the present invention.

[0076] Figure 13 This is a perspective view showing the overall structure of the glass plate manufacturing apparatus according to the second embodiment of the present invention.

[0077] Figure 14 According to Figure 13 The longitudinal section side view obtained by cutting along the D-D line.

[0078] Figure 15 This is a rear view obtained by observing the structure of the main part of the glass plate manufacturing apparatus according to the second embodiment of the present invention from the other side (back side) of the glass strip.

[0079] Figure 16 This is a side view illustrating the operation of the main parts of the glass plate manufacturing apparatus according to the second embodiment of the present invention.

[0080] Figure 17 This is a longitudinal sectional side view for illustrating the operation of the glass plate manufacturing apparatus according to the second embodiment of the present invention.

[0081] Figure 18 This is a longitudinal sectional side view for illustrating the operation of the glass plate manufacturing apparatus according to the second embodiment of the present invention.

[0082] Figure 19 This is a longitudinal sectional side view showing the structure of a glass plate manufacturing apparatus according to a modified example of the second embodiment of the present invention.

[0083] Figure 20 This is a perspective view showing a modified example of a scribing apparatus, which is a component of a glass plate manufacturing apparatus according to the first and second embodiments of the present invention.

[0084] Explanation of reference numerals in the attached figures

[0085] 1 Manufacturing apparatus

[0086] 2. Forming device

[0087] 3. Handling device

[0088] 4. Speed ​​measuring device

[0089] 5. Cutting device

[0090] 6 Forming furnace

[0091] 7 formed body

[0092] 8 edge rollers

[0093] 9 Annealing furnace

[0094] 10 Annealing Rollers

[0095] 11 Cooling Chamber

[0096] 12 support rollers

[0097] 13 Measuring rollers

[0098] 14 Auxiliary rollers

[0099] 15. Engraving device

[0100] 16. Breaking device

[0101] 17. Engraving tools

[0102] 19. Support body (first support rotating body)

[0103] 22. Broken body

[0104] 25 Support mechanism (support part)

[0105] 27 Holding components

[0106] 41 First contact mark (the contact area between the glass ribbon and the edge roller)

[0107] 42 Second contact mark (the contact area between the glass belt and the annealing roller and the support roller)

[0108] 45 guide rollers

[0109] 46. ​​Restricting component (restricting roller)

[0110] 50 sensors

[0111] Gm molten glass

[0112] Gp glass plate

[0113] Lx is the distance between multiple sensors.

[0114] R glass ribbon

[0115] R1 is one end of the glass strip in the width direction (the end on one side of the width direction).

[0116] R2 is the other end of the glass strip in the width direction (the end on the other side of the width direction).

[0117] Ra is the surface (one side) of the glass strip.

[0118] Rb: The back side of the glass strip (the other side).

[0119] Rc glass ribbon cutting target part

[0120] Rm glass strap ear

[0121] Effective area of ​​Rs glass strip

[0122] Ineffective area of ​​Rt glass strip

[0123] Rv - Lower end face of the glass ribbon (cut-off end face)

[0124] Rz is the center (central position) of the glass strip in the width direction.

[0125] S-shaped scribing line

[0126] S1 The beginning of the scribed line

[0127] S2 is the end of the scribed line. Detailed Implementation

[0128] Hereinafter, the glass plate manufacturing apparatus and glass plate manufacturing method according to embodiments of the present invention will be described with reference to the accompanying drawings.

[0129] <First Implementation>

[0130] Figure 1This is a perspective view showing the overall structure of the glass plate manufacturing apparatus 1 according to the first embodiment of the present invention. Figure 2 According to Figure 1 The longitudinal sectional side view obtained by cutting along line A-A. It should be noted that in the following description, [the following will be used to describe the process]. Figure 1 The B-B direction is denoted as the width direction, and... Figure 1 The C-C direction is described as the back direction (the same applies to other figures).

[0131] like Figure 1 as well as Figure 2 As shown, the manufacturing apparatus 1, if roughly divided, includes a forming device 2, a conveying device 3, a speed measuring device 4, and a cutting device 5 in sequence from top to bottom.

[0132] Forming apparatus 2 is disposed within forming furnace 6. Forming furnace 6 is a region for forming glass strip R from molten glass Gm using an overflow-pull method. Forming apparatus 2 includes forming body 7 that causes the molten glass Gm overflowing from the upper end to converge at the lower end to form glass strip R. Furthermore, forming apparatus 2 includes edge rollers 8 that clamp the periphery of the two ends R1 and R2 of the glass strip R formed by forming body 7 in the width direction from both sides in the front and back direction. These edge rollers 8 cool the glass strip R and suppress shrinkage of the glass strip R in the width direction.

[0133] A component of the conveying device 3 is disposed within the annealing furnace 9. The annealing furnace 9 is a region for reducing warping and strain of the glass ribbon R, and has a predetermined temperature gradient that tends downwards within the annealing furnace 9. Furthermore, an annealing roller 10, which is also a component of the conveying device 3, is disposed within the annealing furnace 9. The annealing roller 10 is arranged in multiple stages (two stages in the illustration) and clamps the peripheries of the two ends R1 and R2 in the width direction of the glass ribbon R from both sides in the face-back direction.

[0134] The remaining components of the conveying device 3 are disposed within the cooling chamber 11. The cooling chamber 11 is a region used to cool the glass ribbon R to near room temperature. Gas at room temperature (e.g., clean air) is supplied into the cooling chamber 11, and no heating device such as a heater is provided. Furthermore, a support roller 12, which is the remaining component of the conveying device 3, is disposed within the cooling chamber 11. The support roller 12 is arranged in multiple stages (two stages in the illustration) and clamps the periphery of the two ends R1 and R2 in the width direction of the glass ribbon R from both sides in the front-back direction.

[0135] It should be noted that, in Figure 1 as well as Figure 2In order to facilitate understanding of the structure of the speed measuring device 4 and the cutting device 5, the structure of the annealing furnace 9 and the cooling chamber 11 is simplified. Specifically, the vertical length of the annealing furnace 9 and the cooling chamber 11 is shortened, or the number of stages of the annealing roller 10 and the support roller 12 is reduced. Furthermore, in the following description, for convenience, the following will be... Figure 1 The end R1 of the glass strip R in the width direction is denoted as one end, and the end R2 in the other width direction is denoted as the other end (the same applies to the other figures). Furthermore, the surface Ra of one side of the glass strip R is denoted as the surface, and the surface Rb of the other side is denoted as the back side (the same applies to the other figures).

[0136] The speed measuring device 4 includes: a measuring roller 13 disposed on the surface Ra side of the glass strip R; and an auxiliary roller 14 disposed on the back side Rb side of the glass strip R. The measuring roller 13 and the auxiliary roller 14 are arranged opposite each other on both sides of the glass strip R in the surface-back direction. The measuring roller 13 is in contact with the surface Ra of the glass strip R, and the auxiliary roller 14 is in contact with the back side Rb of the glass strip R. It should be noted that the detailed structure of the speed measuring device 4 and its surrounding structure will be described later.

[0137] The cutting device 5 includes: a scribing device 15, which forms a scribing line S extending along the width direction on the back side Rb of the glass strip R; and a breaking device 16, which breaks the glass strip R at the location where the scribing line S is formed to obtain a single sheet of glass.

[0138] The engraving device 15 includes: an engraving tool 17 (in...) Figure 2 (For convenience, it is shown in solid line in the diagram), which is located on the back side Rb of the glass strip R; and the traveling mechanism 18 (in Figure 2 (For convenience, it is illustrated with a dashed line). It is similarly positioned on the back side Rb of the glass strip R, and the marking tool 17 travels along the width direction. In this embodiment, the marking tool 17 is composed of a disc-shaped member with a blade at its periphery. When forming the marking line S on the glass strip R, the marking tool 17 travels from one end R1 side of the glass strip R towards the other end R2 side via the operation of the travel mechanism 18. The marking tool 17 is configured to be integrated with the travel mechanism 18 and move along the surface and back directions as well as the vertical direction.

[0139] Furthermore, the scribing apparatus 15 includes a support body 19 disposed on the surface Ra side of the glass strip R. The support body 19 and the scribing tool 17 are disposed on opposite sides of the glass strip R in the surface-back direction. The support body 19 is composed of a member that is longer in the width direction and has a support surface 19a opposite to the surface Ra of the glass strip R. The support surface 19a is a plane that extends in a straight line in the width direction and is parallel to the vertical plane. The support body 19 is configured to move in the surface-back direction and in the vertical direction.

[0140] The breaking device 16 consists of an upper breaking device 20 disposed on the upper side and a lower breaking device 21 disposed on the lower side.

[0141] The upper breaking device 20 includes a breaking body 22 disposed on the surface Ra side of the glass strip R. The breaking body 22 is composed of a member that is longer in the width direction. Furthermore, the breaking body 22 has an abutting end 22a opposite to the surface Ra of the glass strip R. The abutting end 22a is bent in such a way that it protrudes toward the front end side when viewed from the side.

[0142] Furthermore, the upper breaking device 20 includes a dust collector 23 disposed on the back side Rb of the glass strip R. The dust collector 23 is longer in the width direction. Moreover, the dust collector 23 has a suction section (not shown) that sucks in glass dust generated when the glass strip R is broken. Both the breaking body 22 and the dust collector 23 are configured to move in the back direction and the up and down direction.

[0143] The lower breaking device 21 includes a support mechanism 25 that supports the cutting object portion Rc, which is the object from which a single sheet of glass is cut from the glass strip R. The support mechanism 25 has a pair of arm members 24 disposed at one end R1 and the other end R2 in the width direction of the glass strip R. Both arm members 24 extend in the vertical direction. Furthermore, the support mechanism 25 has holding members 27 installed at multiple locations (two locations in the illustration) in the vertical direction of each pair of arm members 24. Each holding member 27 can be opened and closed to an open state, indicated by solid lines, and a closed state, indicated by dashed lines. The pair of arm members 24 are configured to be integral and rotate in a vertical plane orthogonal to the width direction.

[0144] Here, the basic operation of this manufacturing apparatus 1, namely the operation of the engraving device 15 and the breaking device 16, will be explained.

[0145] First, such as Figure 3 As shown, when the glass strip R moves downward, the arm member 24 of the breaking device 16 (lower breaking device 21) moves downward in tandem, while the holding member 27 holds the cutting target portion Rc of the glass strip R. After this holding, the arm member 24 also moves downward in tandem with the glass strip R. At this time, the scribing tool 17 and support body 19 of the scribing device 15, the breaking body 22 of the breaking device 16 (upper breaking device 20), and the dust collector 23 are in the retracted position and ready for use.

[0146] Next, as Figure 4As shown, the scribing tool 17 and the support body 19 move downwards while following the glass strip R, moving from a retracted position to a contact position. Furthermore, with the support body 19 in contact with the surface Ra of the glass strip R, the scribing tool 17 travels from one end R1 side of the glass strip R towards the other end R2 side. This forms a scribing line S extending in the width direction on the back surface Rb of the glass strip R. During the period until the formation of the scribing line S is completed, the scribing tool 17 and the support body 19 move downwards following the glass strip R. After the formation of the scribing line S is completed, the scribing tool 17 and the support body 19 move back to the initial retracted position.

[0147] After that, as Figure 5 as well as Figure 6 As shown, the broken body 22 and the dust collector 23 move downwards while following the glass strip R, moving from the retracted position to the contact position. In this case, the abutting end 22a of the broken body 22 contacts the surface Ra of the glass strip R, while the dust collector 23 is slightly separated from the back surface Rb of the glass strip R. At this moment, as... Figure 6 As shown, when viewed from above, the glass strip R extends in a straight line along the width direction, mimicking the straight shape of the abutting end 22a of the broken body 22.

[0148] In this state, such as Figure 7 As shown, the pair of arm members 24 become one and rotate, thereby shifting the orientation of the pair of arm members 24 from a vertical orientation to an inclined orientation. Consequently, a bending stress, accompanied by longitudinal bending, acts at the location where the scribe line S of the glass strip R is formed. Under the action of this bending stress, the glass strip R is broken along the scribe line S, as... Figure 8 As shown, a glass plate Gp is ​​cut from the glass strip R. It should be noted that the glass dust generated during this cutting process is sucked in by the dust collector 23.

[0149] Here, the thickness of the glass strip R is 10 μm to 1000 μm. The thinner the glass strip R, the easier it is for wrinkles to form on the glass strip during the movement of the scribing tool. Therefore, the effect of the present invention, which makes it less susceptible to the influence of wrinkles and enables accurate measurement of the glass strip's movement speed, becomes significant. Therefore, the upper limit of the thickness of the glass strip R is preferably 700 μm or less, more preferably 500 μm or less. The length of the glass strip R in the width direction is 500 mm to 3800 mm. In addition, the glass plate Gp cut from the glass strip R is used as a glass substrate and cover glass in panel displays such as liquid crystal displays and organic EL displays.

[0150] Next, the detailed structure of the speed measuring device 4 and its surrounding structure will be described.

[0151] Figure 9This is a top view showing the measuring roller 13 and auxiliary roller 14 of the speed measuring device 4 clamping the glass strip R. As shown in the figure, the measuring roller 13 is in contact with the surface Ra of the glass strip R. The auxiliary roller 14 is in contact with the back surface Rb of the glass strip R.

[0152] A first roller shaft 30 is integrally mounted on the measuring roller 13, extending from one end R1 in the width direction of the glass belt R. The first roller shaft 30 is supported by a plurality of bearings 31 for free rotation. Thus, the measuring roller 13 is cantilevered and capable of rotation. The measuring roller 13 is held in a position not to move in any direction, either vertically or horizontally.

[0153] Furthermore, the measuring roller 13 is a free roller. The outer periphery or the entire measuring roller 13 is formed of heat-resistant rubber. Fluororubber, ethylene propylene rubber, nitrile rubber, etc. are used as heat-resistant rubbers.

[0154] The measuring roller 13 rotates in contact with the surface Ra of the glass strip R, thereby measuring the moving speed of the glass strip R. As a structure for this purpose, the speed measuring device 4 includes a rotational speed detector 32 that detects the rotational speed of the measuring roller 13. In this embodiment, a rotary encoder is used as the rotational speed detector 32. Furthermore, the speed measuring device 4 includes a calculation unit 33 that calculates the moving speed of the glass strip R based on the rotational speed of the measuring roller 13 detected by the rotational speed detector 32. In this calculation unit 33, the circumferential speed of the measuring roller 13 (the moving speed of the outer circumferential surface of the measuring roller 13) is calculated as the moving speed of the glass strip R.

[0155] A signal indicating the moving speed of the glass strip R as measured by the measuring roller 13 (a signal indicating the measurement result of the measuring roller 13) is sent to the cutting device 5 (the scribing device 15 and the breaking device 16). As a result, the scribing cutter 17, the support body 19, the breaking body 22, the dust collector 23, and the pair of arm members 24 move downward in accordance with the moving speed of the glass strip R measured by the measuring roller 13.

[0156] A second roller shaft 34 extending toward one end R1 of the glass belt R is integrally mounted on the auxiliary roller 14. The second roller shaft 34 is supported by a plurality of (two in the illustration) bearings 35 for free rotation. Thus, the auxiliary roller 14 is cantilevered and rotatable. The auxiliary roller 14 is held in a position not to move in the vertical direction.

[0157] Furthermore, the auxiliary roller 14 is a drive roller that is rotated by a motor M such as a servo motor. The rotational speed of the motor M is variably controlled by the controller 36.

[0158] Additionally, the auxiliary roller 14 is pressed towards the measuring roller 13 by a pressing mechanism 37 such as a cylinder. Thus, a pressing force is applied to the measuring roller 13 from the auxiliary roller 14 via the glass belt R.

[0159] Furthermore, the rotational speed of the auxiliary roller 14 is controlled in such a way that it follows the moving speed of the glass strip R measured by the measuring roller 13. Here, a signal indicating the measurement result of the measuring roller 13 is input to the controller 36. Therefore, in this case, control is performed by the controller 36 based on the signal indicating the measurement result of the measuring roller 13 (the signal sent from the arithmetic unit 33).

[0160] Based on the structure of the speed measuring device 4 described above, the following effects are achieved. Since the measuring roller 13 is a free roller that contacts the surface Ra of the glass strip R, slippage between it and the surface Ra of the glass strip R is less likely to occur compared to the case where it is a drive roller. Therefore, the moving speed of the glass strip R can be accurately measured. Furthermore, the measuring roller 13 is subjected to pressing pressure from the auxiliary roller 14, further reducing the likelihood of slippage between it and the surface Ra of the glass strip R.

[0161] Furthermore, at least the outer periphery of the measuring roller 13 is made of heat-resistant rubber, which makes it less prone to slippage between it and the surface Ra of the glass belt R. It is also less susceptible to the temperature (high temperature) of the glass belt R, thus extending the lifespan of the measuring roller 13.

[0162] On the other hand, since the auxiliary roller 14 is a drive roller and its rotational speed is variably controlled, during startup or maintenance of this manufacturing apparatus 1, if the auxiliary roller 14 is brought into direct contact with the measuring roller 13 and rotated, it is possible to confirm whether the measuring roller 13 operates accurately. Specifically, with the auxiliary roller 14 in direct contact with the measuring roller 13, by checking whether the rotational speed of the measuring roller 13 is also accurately N times the rotational speed of the auxiliary roller 14, it is possible to check in advance whether the measuring roller 13 operates accurately.

[0163] Furthermore, the rotational speed of the auxiliary roller 14 is controlled to follow the moving speed of the glass strip R measured by the measuring roller 13, thus ensuring that the moving speed of the glass strip R is accurately matched with the rotational speed of the auxiliary roller 14. In detail, assuming that the rotational speeds of the annealing roller 10 and the support roller 12 of the conveying device 3 follow the moving speed of the glass strip R measured by the measuring roller 13, slippage may inevitably occur between these rollers 10, 12 and the glass strip R. Therefore, it is difficult to accurately match the rotational speeds of these rollers 10, 12 with the moving speed of the glass strip R. In contrast, as described above, if the rotational speed of the auxiliary roller 14 follows the moving speed of the glass strip R measured by the measuring roller 13, such an undesirable situation will not occur.

[0164] Furthermore, since the measuring roller 13 and the auxiliary roller 14 are positioned below the conveying device 3 and above the marking device 15, they do not obstruct the measurement of the moving speed of the glass ribbon R. That is, when the measuring roller 13 and the auxiliary roller 14 are positioned above the conveying device 3, the glass ribbon R may bend between the conveying device 3 and the forming device 2, making it impossible to accurately measure the moving speed of the glass ribbon R using the measuring roller 13. On the other hand, when the measuring roller 13 and the auxiliary roller 14 are positioned below the marking device 15, the marking line S formed on the glass ribbon R passes through the measurement area measured by the measuring roller 13 and the auxiliary roller 14, which may prevent accurate measurement of the moving speed of the glass ribbon R or cause the glass ribbon R to break at the starting point of the marking line S. In contrast, as described above, if the measuring roller 13 and the auxiliary roller 14 are positioned below the conveying device 3 and above the marking device 15, such adverse situations will not occur.

[0165] The auxiliary roller 14 applies pressure to the measuring roller 13 from the back side (Rb) of the glass strip R. The scribing cutter 17 moves while simultaneously applying pressure to the support body 19 from the back side (Rb) of the glass strip R. Therefore, the directions of pressure application are aligned between the auxiliary roller 14 and the scribing cutter 17. Consequently, oscillation is less likely to occur on the glass strip R when the scribing cutter 17 moves.

[0166] Figure 10 This is a front view of the main parts of the manufacturing apparatus 1, viewed from the Ra side of the glass strip R. As shown in the figure, the annealing roller 10 and the support roller 12 of the conveying device 3 are positioned at the center side in the width direction, closer to the edge roller 8. It should be noted that in this embodiment, the annealing roller 10 and the support roller 12 are positioned at the same location in the width direction.

[0167] Therefore, the contact mark 41 (hereinafter referred to as the first contact mark 41) in the glass belt R that contacts the annealing roller 10 and the support roller 12 is located on the central side in the width direction compared to the contact mark 42 (hereinafter referred to as the second contact mark 42) in the glass belt R that contacts the edge roller 8. In this figure, the first contact mark 41 is illustrated as a striped area marked with relatively large-spaced crosshairs, and the second contact mark 42 is illustrated as a striped area marked with relatively small-spaced crosshairs. In this case, the first contact mark 41 and the second contact mark 42 are separated in the width direction, and there is a striped gap area 43 (the area 43 without crosshairs) between the first contact mark 41 and the second contact mark 42.

[0168] Figure 11This is a top view showing a cross-section of the glass strip R when it is cut along its width direction. As shown in the figure, an ear portion Rm with a thickness greater than the central portion in the width direction is formed in the region on the side of one end R1 in the width direction of the glass strip Rm. Furthermore, a concave-convex region Rn is formed in the region on the side of one end R1 in the width direction of the ear portion Rm. The region on which this concave-convex region Rn is formed is the second contact mark 42. In addition, the region in the ear portion Rm where the concave-convex region Rn is not formed exists within the striped gap region 43. It should be noted that the above description also applies to the region on the side of the other end R2 in the width direction of the glass strip R. Therefore, the same reference numerals are used for the region on the side of the other end R2 in the width direction of the glass strip R shown in this figure to refer to the common constituent elements as described above.

[0169] Here, as Figure 10 As shown, the measuring roller 13 is positioned in the region of the glass belt R near one end R1, at the center Rz in the width direction. This achieves the effect shown below. That is, as... Figure 12 As shown, when the scribing tool 17 moves from one end R1 side to the other end R2 side in the width direction of the glass strip R in order to form the scribing line S, wrinkles Rp are sometimes generated in the glass strip R. In detail, wrinkles Rp are generated in the latter half of the period from the beginning of the formation of the scribing line S by the scribing tool 17 to the end of the formation.

[0170] Therefore, the folds Rp in Figure 10 The region on the side of the end S2 of the scribe line S in the glass belt R shown is generated. Therefore, when the measuring roller 13 is positioned in the region on the side of the end S2 of the scribe line S in the glass belt R, it is difficult to accurately measure the moving speed of the glass belt R due to the influence of the wrinkles Rp.

[0171] Therefore, if the measuring roller 13 is positioned in the region on the side of the beginning S1 of the scribe line S in the glass belt R, that is, in the region on the side of the end R1 of the glass belt R in the width direction as described above, the moving speed of the glass belt R can be accurately measured without being affected by the wrinkles Rp.

[0172] Based on the following Figure 10 In the description, the first contact mark 41, the second contact mark 42, the ear Rm and the gap region 43 mean the aforementioned elements 41, 42, Gm and 43 existing on the side of one end R1 in the width direction of the glass strip R.

[0173] The measuring roller 13 is positioned at a location closer to the center of the width direction than the first contact mark 41. Therefore, the measuring roller 13 is positioned at a location closer to the center of the width direction than the second contact mark 42, the ear portion Rm, and the gap region 43. It should be noted that the separation distance L1 from the center Rz of the glass strip R in the width direction to the measuring roller 13 is longer than the separation distance L2 from the second contact mark 42 to the measuring roller 13.

[0174] Based on this configuration, the measuring roller 13 can accurately measure the moving speed of the glass strip R for the following reasons. Specifically, because the second contact mark 42 formed on the glass strip R has an unevenness Rn, when the measuring roller 13 is configured to interfere with the second contact mark 42, the moving speed of the glass strip R cannot be accurately measured due to the influence of the unevenness Rn. Furthermore, the formation site of the second contact mark 42 has significant residual stress, so there is a possibility that the formation site of the second contact mark 42 may break during the downward transport of the glass strip R. Due to this breakage, the measuring roller 13 also cannot accurately measure the moving speed of the glass strip R. It should be noted that the same problem occurs with the ear Rm. Therefore, by configuring the measuring roller 13 as described above so as not to interfere with the ear Rm including the second contact mark 42, the moving speed of the glass strip R can be accurately measured.

[0175] Furthermore, glass powder and other particles adhering to the annealing roller 10 and the support roller 12 are pressed against the first contact mark 41 by the annealing roller 10 and the support roller 12, resulting in the formation of tiny cracks. Therefore, the strength at the crack formation site of the glass strip R is low. Consequently, if the crack comes into contact with the measuring roller 13, it will cause the glass strip R to break. Therefore, by configuring the measuring roller 13 in a manner that does not interfere with the first contact mark 41 as described above, the moving speed of the glass strip R can be accurately measured.

[0176] As a further structural feature, as shown in the figure, the glass strip R has an effective region Rs, which is the central area in the width direction, and ineffective regions Rt, which are the entire areas of one end R1 and the other end R2 in the width direction of the effective region Rs. The effective region Rs is the area used as the product glass sheet. The ineffective region Rt is the area that is cut off as an unnecessary part in a later process. Furthermore, the measuring roller 13 is disposed within the ineffective region Rt. This prevents foreign matter from adhering to the effective region Rs or causing damage to the effective region Rs, thereby improving the quality of the product glass sheet.

[0177] Here, the measuring roller 13 can also be disposed within the striped gap region 43. Therefore, the measuring roller 13 may interfere with areas in the ear portion Rm where no unevenness Rn is formed. However, areas in the ear portion Rm where no unevenness Rn is formed may have residual stress and exhibit some thickness variation. Therefore, it is preferable that the measuring roller 13 is disposed within the striped gap region 43 in a manner that does not interfere with the entire area of ​​the ear portion Rm.

[0178] Furthermore, unlike the illustration, when the position of the annealing roller 10 in the width direction differs from that of the support roller 12, the length of the first contact mark 41 in the width direction becomes longer, or the two first contact marks 41 are separated in the width direction. Even in this case, the measuring roller 13 is positioned so as not to interfere with the first contact marks 41. Therefore, the measuring roller 13 may also be positioned in the striped gap region between the two first contact marks 41.

[0179] It should be noted that, in the illustration, in the second contact mark 42, the portion where the measuring roller 13 is positioned at its height is located closer to the center of the width direction than the position near the bottom of the edge roller 8. In this case, the position of the second contact mark 42 in the width direction means the position in the width direction at the height position where the measuring roller 13 is positioned. Therefore, "position closer to the center of the width direction than the second contact mark 42" means "position closer to the center of the width direction than the second contact mark 42 at the height position where the measuring roller 13 is positioned".

[0180] The above is based on Figure 10 The same explanation applies to the auxiliary roller 14. It should be noted that the length of the auxiliary roller 14 in the width direction is preferably the same as the length of the measuring roller 13 in the width direction, but it is also possible that the length of one in the width direction is longer than the length of the other.

[0181] The surrounding structure of the speed measuring device 4 is shown below.

[0182] like Figure 1 as well as Figure 10 As shown, a guide roller 45 is positioned at a height corresponding to the measuring roller 13 in a region of the glass strip R that is closer to the other end R2 than the center Rz in the width direction. In the illustration, the guide roller 45 consists of a pair of rollers positioned in a portion in the width direction and clamping the glass strip R from both sides in the face-back direction. Both guide rollers 45 are free rollers. It should be noted that... Figure 10 The first contact mark 41, the second contact mark 42, the ear Rm, and the gap region 43 shown are also formed in the same manner with respect to the back surface Rb of the glass strip R.

[0183] Preferably, the pair of guide rollers 45 are positioned in the same manner as the measuring roller 13 described above, in the surface Ra and back surface Rb of the glass strip R, relative to the first contact mark 41, second contact mark 42, ear Rm, and gap region 43 formed on the other end R2 side in the width direction of the glass strip R. In this case, the clamping force of the pair of guide rollers 45 is smaller than the pressing force exerted on the measuring roller 13 from the auxiliary roller 14, so the above-mentioned positional relationship may be partially or completely different from that of the measuring roller 13 described above. However, the pair of guide rollers 45 are preferably configured so as not to interfere with the second contact mark 42 or the ear Rm.

[0184] In the illustration, a pair of guide rollers 45 are positioned at the same height as the measuring roller 13, but their vertical positions may differ slightly from those of the measuring roller 13. However, even in this case, it is preferable that they are positioned at substantially the same height. In this case, the pair of guide rollers 45 are positioned above the marking device 15 and below the conveying device 3 (the lowermost support roller 12).

[0185] If a pair of guide rollers 45 are set in this way, the swaying of the glass strip R can be suppressed at the height position corresponding to the measuring roller 13, so that the moving speed of the glass strip R can be accurately measured without being affected by the swaying.

[0186] Furthermore, a limiting member 46 (restricting roller 46 in the illustration) is positioned below the measuring roller 13 and above the marking device 15, clamping the glass strip R from both sides in the direction of the back of the watch and restricting the swing of the glass strip R. The limiting roller 46 is positioned in the region of the glass strip R near one end R1 of the center Rz in the width direction and in the region of the glass strip R near the other end R2 of the center Rz in the width direction. Thus, the glass strip R is clamped by two pairs of limiting rollers 46. The vertical separation distance L3 between the two pairs of limiting rollers 46 and the measuring roller 13 is shorter than the vertical separation distance L4 between the two pairs of limiting rollers 46 and the marking device 15 (see reference). Figure 10 In addition, the vertical separation distance L3 between the two pairs of limiting rollers 46 and the measuring roller 13 is shorter than the vertical separation distance L5 between the two pairs of limiting rollers 46 and the lowest support roller 12.

[0187] Preferably, the two pairs of limiting rollers 46 are positioned in the same manner as the measuring roller 13 described above, with the first contact mark 41, the second contact mark 42, and the gap region 43 formed on one end R1 and the other end R2 respectively in the width direction of the glass strip R. In this case, the clamping force of each pair of limiting rollers 46 is smaller than the pressing force exerted on the measuring roller 13 from the auxiliary roller 14, so the above-mentioned positional relationship may be partially or completely different from that of the measuring roller 13 described above. However, the two pairs of limiting rollers 46 are preferably arranged so as not to interfere with the second contact mark 42 or the ear Rm.

[0188] By configuring the limiting roller 46 in this way, the swaying of the glass strip R caused by the scribing device 15 during the formation of the scribing line S on the glass strip R can be suppressed, thus preventing the transmission of this sway to the positioning of the measuring roller 13 and the auxiliary roller 14. This allows for accurate measurement of the moving speed of the glass strip R. It should be noted that the limiting roller 46 is preferably a free roller. If the limiting roller 46 is a free roller, the moving speed of the glass strip R can be accurately measured using the measuring roller 13 without causing any change in the moving speed of the glass strip R.

[0189] Next, a method for manufacturing a glass plate according to the first embodiment of the present invention will be described. This manufacturing method includes a forming process, a transport process, a speed measurement process, and a cutting process. Furthermore, the cutting process includes a scribing process and a breaking process.

[0190] The forming process is a process of forming glass strip R from molten glass Gm using forming device 2 (in this embodiment, forming body 7 and edge roller 8).

[0191] The transport process is a process of transporting the glass strip R downward using the transport device 3 (in this embodiment, the annealing roller 10 and the support roller 12).

[0192] The speed measurement process is a process in which the speed measuring device 4 measures the moving speed of the glass belt R during the handling process. In the speed measurement process, the moving speed of the region of the glass belt R near one end R1, which is located in the width direction from the center Rz, is measured.

[0193] The cutting process is a process of cutting a single sheet of glass Gp from the glass strip R using the scribing device 15 and the breaking device 16.

[0194] The scribing process is a process in which scribing device 15 forms scribing lines S from one end R1 side to the other end R2 side in the width direction of the glass strip R.

[0195] The breaking process is a process in which the glass strip R is broken at the position where the scribed line S is formed by the breaking device 16 to obtain a single glass plate Gp.

[0196] <Second Implementation>

[0197] Figure 13 This is a schematic perspective view showing the overall structure of the glass plate manufacturing apparatus 1 according to the second embodiment of the present invention. Figure 14 According to Figure 13 The figure shows a longitudinal sectional side view obtained by cutting along the D-D line. As shown in these figures, the manufacturing apparatus 1 of this second embodiment differs from the manufacturing apparatus 1 of the first embodiment described above in that the speed measuring device 4 measures the moving speed of the glass strip R in a non-contact manner. Specifically, the speed measuring device 4 of this second embodiment includes multiple (two in the illustration) sensors 50 for measuring the moving speed of the glass strip R in a non-contact manner. These sensors 50 are positioned in fixed locations. With this structure, the moving speed of the glass strip R can be accurately measured without damaging the glass strip R or causing the slippage problems that occur when using a contact-type speed measuring device.

[0198] The structures of other components, namely forming device 2, conveying device 3, and cutting device 5 (scribing device 15 and breaking device 16), are the same as those in the first embodiment described above. Therefore, regarding the common components in both embodiments, Figure 13 as well as Figure 14 The same reference numerals are used in the figures and their descriptions are omitted (the same applies to other figures that appear later).

[0199] like Figure 13 as well as Figure 14 As shown, two sensors 50 are positioned at different locations in the vertical direction in the region below the location where the glass strip R is broken by the breaking device 16 (in the example, the region below the upper breaking device 20). Specifically, the two sensors 50 are arranged such that the respective detection positions (measurement positions) Rw, Rx exist in the glass strip R in a region lower than the breakage location caused by the breaking device 16. Furthermore, the two sensors 50 detect the position of the lower end face (cut surface) Rv of the glass strip R formed by the breaking device 16. In this embodiment, the two sensors 50 point in the same direction without tilting relative to either the vertical direction or the front / back direction, but one sensor 50 may point in a different direction than the other.

[0200] In the illustration, two sensors 50 are positioned on the back side Rb of the glass strip R. These two sensors 50 can detect the presence or absence of the glass strip R. Specifically, reflective laser sensors, ultrasonic sensors, thermal imagers, etc., are used as the two sensors 50. It should be noted that transmissive laser sensors, etc., can also be used as the two sensors 50. However, in this case, unlike the illustration, the components (light-projecting part and light-receiving part) of each sensor 50 need to be positioned on both the surface Ra side and the back Rb side of the glass strip R. When using a transmissive laser sensor, accurate measurement can be performed without being affected by factors such as oscillation of the glass strip R.

[0201] On the other hand, if the two sensors 50, consisting of a reflective laser sensor, an ultrasonic sensor, and a thermal imager, are configured only on the back side Rb of the glass strip R, as shown in the example, the manufacturing apparatus 1 can be made compact. Specifically, when the orientation of the cut-out portion Rc of the glass strip R changes from a vertical to an inclined orientation when the glass strip R is broken, the cut-out portion Rc moves away from the two sensors 50. Therefore, the two sensors 50 can be configured close to the vertically oriented glass strip R, thus achieving a compact manufacturing apparatus 1. It should be noted that although this advantage is not obtained, the two sensors 50 can also be configured only on the surface Ra side of the glass strip R. It should also be noted that the advantage of accurate measurement unaffected by the swaying of the glass strip R is also obtained when a thermal imager is used as described above.

[0202] Here, the glass strip R is a continuously formed transparent body, making it difficult to measure the moving speed of the glass strip R in a non-contact manner using optical mechanisms or the like. In contrast, if the structure detects the position of the lower end face Rv of the glass strip R as described above, the position of the lower end face Rv can be easily detected non-contactly using the sensor 50 described above, which detects the presence or absence of the glass strip R, thereby accurately measuring the moving speed.

[0203] It should be noted that, in the illustration, the presence of the limiting roller 46 provides the advantage of being able to limit the swaying of the glass strip R above the marking device 15. While this advantage is not present, the limiting roller 46 may not be included.

[0204] like Figure 14As shown, the speed measuring device 4 includes a calculation unit 51. The calculation unit 51 uses two sensors 50 to detect the time when the lower end face Rv of the glass strip R is positioned and the distance Lx between the two sensors 50 to calculate the moving speed of the glass strip R. In this case, the distance Lx between the two sensors 50 represents the vertical separation distance of the sensing portions 50a of each of the two sensors 50. Furthermore, if we consider the possibility that the orientations of the two sensors 50 are different as described above, then the distance Lx between the two sensors 50 represents the vertical separation distance of each detection position (measuring position) Rw, Rx of the two sensors 50 on the glass strip R. The moving speed of the glass strip R calculated by the calculation unit 51 is the value obtained by dividing the distance Lx between the two sensors 50 by the difference in the times detected by the two sensors 50.

[0205] Figure 15 This is a front view of the main parts of the manufacturing apparatus 1, viewed from the back side Rb of the glass strip R. It should be noted that, as shown in this figure, the first contact mark 41, the second contact mark 42, and the gap region 43 formed on the back side Rb of the glass strip R are identical to the first contact mark 41, the second contact mark 42, and the gap region 43 formed on the surface Ra of the glass strip R (see reference). Figure 10 In the same way.

[0206] like Figure 15 As shown, the two sensors 50 are configured to measure the moving speed of the region on the side of the central Rz in the width direction of the glass strip R, near one end R1 (which is also the region on the side of the beginning S1 of the scribing line S). Therefore, the two sensors 50 are not affected by the wrinkles Rp that may occur in the region on the side of the end S2 of the scribing line S in the glass strip R when the scribing tool 17 moves, and can accurately measure the moving speed of the glass strip R.

[0207] Furthermore, the two sensors 50 are positioned at the same location in the width direction. Specifically, the sensing parts 50a of each of the two sensors 50 are positioned at the same location in the width direction. More specifically, the two sensors 50 are arranged such that their respective detection positions (measurement positions) on the glass strip R are at the same location in the width direction. In this way, even if the lower end face Rv of the glass strip R is cracked, missing, or cut at an angle—that is, if the lower end face Rv of the glass strip R does not extend in a straight line along the horizontal direction—the moving speed of the glass strip R can still be accurately measured.

[0208] Furthermore, the two sensors 50 are configured to measure the movement speed of the region on the central side of the glass strip R, which is closer to the ear portion Rm in the width direction. Here, the ear portion Rm has significant residual stress, so there is a possibility that the ear portion Rm may break and become inaccurate during the measurement process (from the time the upper sensor 50 detects the position of the lower end face Rv until the lower sensor 50 detects the position of the lower end face Rv). Therefore, even if the movement speed of the ear portion Rm is measured, the movement speed of the glass strip R cannot be accurately measured. In contrast, if the movement speed of the region on the central side of the ear portion Rm in the width direction is measured as described above, such an undesirable situation will not occur.

[0209] Furthermore, the two sensors 50 are configured to measure the moving speed of the region between the beginning S1 and the end S2 of the scribe line S in the glass strip R. Here, the region of the glass strip R closer to one end R1 than the beginning S1 of the scribe line S (and the same applies to the region closer to the other end R2 than the end S2 of the scribe line S) does not break along the scribe line S, thus the cut end face (lower end face) Rv of the glass strip R is prone to breakage. Therefore, there is a possibility that after the cut end face Rv is detected by the upper sensor 50 and before it is detected by the lower sensor 50, new defects or damage may occur on the cut end face Rv in the region closer to one end R1 than the beginning S1 of the scribe line S. As a result, the moving speed of the glass strip R cannot be accurately measured in the region closer to one end R1 than the beginning S1 of the scribe line S. In contrast, if the area is between the beginning S1 and the end S2 of the scribe line S as described above, then the cut end face Rv becomes the end face that is broken along the scribe line S, and thus such an undesirable situation will not occur.

[0210] Furthermore, the two sensors 50 are configured to detect the position of the lower end face Rv of the glass strip R before the cutting target portion Rc of the glass strip R changes from a vertical to an inclined posture due to the support mechanism 25 of the breaking device 16. Here, the support mechanism 25 is configured to detect the position of the lower end face Rv of the glass strip R before the cutting target portion Rc of the glass strip R changes from a vertical posture to an inclined posture. Figure 16As shown, after the cutting target portion Rc of the glass strip R changes from a vertical to an inclined posture, the position of the lower end face Rv of the cutting target portion Rc moves upward relative to it by δ1 (shown by the solid line in the figure) compared to when the cutting target portion Rc moved downward as it originally did in the vertical posture (shown by the dotted line in the figure). Therefore, when the lower sensor 50 is configured to detect the position of the lower end face Rv of the cutting target portion Rc after the aforementioned posture change, the time when the lower sensor 50 detects the lower end face Rv of the cutting target portion Rc is delayed by an amount corresponding to the aforementioned δ1. It should be noted that the same applies when the upper sensor 50 is configured to detect the position of the lower end face Rv of the cutting target portion Rc after the aforementioned posture change. Therefore, it is impossible to accurately measure the moving speed of the glass strip R. In contrast, if the two sensors 50 are configured as described above to detect the position of the lower end face Rv of the cut-out object Rc before the aforementioned attitude change, such an undesirable situation will not occur.

[0211] Furthermore, a signal indicating the moving speed of the glass strip R, calculated by the speed measuring device 4 (calculation unit 51), is sent to the cutting device 5 (grinding device 15 and breaking device 16). As a result, the scribing cutter 17, support 19, breaking device 22, dust collector 23, and a pair of arm members 24 move downwards following the moving speed of the glass strip R calculated by the calculation unit 51. Here, it is considered that the downward moving speed of the cutting device 5 should match the conveying speed of the glass strip R carried by the conveying device 3, but slippage may inevitably occur between the rollers 10 and 12 of the conveying device 3 and the glass strip R. Therefore, it is difficult to accurately match the moving speed of the glass strip R with the moving speed of the cutting device 5. In contrast, if the moving speeds of the components 17, 19, 22, 23, and 24 of the cutting device 5 are made to match the moving speed of the glass strip R calculated by the calculation unit 51 as described above, such an undesirable situation will not occur.

[0212] In the above structure, the measurement of the moving speed of the glass strip R by the speed measuring device 4 is preferably as follows: Figure 17 As shown, this occurs when the holding member 27 of the support mechanism 25 in the breaking device 16 moves downward while holding the cutting target portion Rc of the glass strip R. That is, as... Figure 18As shown, when the glass strip R warps longitudinally, from the time the glass strip R is broken by the breaking device 16 until it is held by the holding member 27, the lower end face Rv of the glass strip R swings vertically due to the warping. Therefore, the speed measuring device 4 cannot accurately measure the moving speed of the glass strip R. Thus, the speed measuring device 4 preferably measures the moving speed of the glass strip R only when the holding member 27 holds the glass strip R and moves it downwards, and does not measure the moving speed of the glass strip R at other times. During the period when the moving speed of the glass strip R is not measured, it is sufficient that the moving speeds of the components 17, 19, 22, 23, and 24 of the cutting device 5 follow the moving speed of the glass strip R most recently measured by the speed measuring device 4. It should be noted that the speed measuring device 4 can also measure the moving speed of the glass strip R continuously without causing problems due to the warping of the glass strip R.

[0213] Alternatively, as a variation of this embodiment, the two sensors 50 of the speed measuring device 4 may each detect the scribe lines S formed on the glass strip R, thereby measuring the moving speed of the glass strip R. In this case, the arrangement of the two sensors 50 in the width direction is adjusted to... Figure 15 The configuration measures the moving speed of the region between the beginning S1 and the end S2 of the scribed line S. Correspondingly, the vertical configuration of the two sensors 50 is as follows: Figure 19 As shown. That is, the two sensors 50 are disposed below the scribing device 15 and above the breaking device 16. In detail, the two sensors 50 are disposed in a region where their respective detection positions (measurement positions) Rw and Rx are located below the location where the scribing line S is formed by the scribing device 15 on the glass strip R and above the location where the glass strip R is broken by the breaking device 16.

[0214] Furthermore, the calculation unit 51 of the speed measuring device 4 uses two sensors 50 to detect the time at which the position of the scribe line S formed on the glass strip R is determined, as well as the distance between the two sensors 50, to calculate the moving speed of the glass strip R. In this case, the moving speed of the glass strip R calculated by the calculation unit 51 is the value obtained by dividing the distance between the two sensors 50 by the difference in the time when the two sensors 50 detect the scribe line S. In this modified example, a thermal imager, a camera (e.g., an industrial camera for inspection), etc., are used as the two sensors 50.

[0215] Next, the manufacturing method of the glass plate according to the second embodiment will be described. This manufacturing method includes a forming process, a handling process, a cutting process, and a speed measurement process.

[0216] The forming process, the handling process, and the cutting process are the same as the manufacturing method of the first embodiment described above.

[0217] The speed measurement process is a process of measuring the moving speed of the glass strip in a non-contact manner. In this speed measurement process, a non-contact sensor is used.

[0218] The above describes the embodiments of the present invention, but the embodiments of the present invention are not limited thereto, and various modifications can be made without departing from the spirit of the present invention.

[0219] For example, the marking device 15 in the above embodiment can also be replaced with Figure 20 The engraving device 15 is shown. Specifically, in... Figure 20 In the scribing apparatus 15 shown, the support body 19 that supports the scribing cutter 17 disposed on the back side Rb of the glass strip R from the surface Ra side of the glass strip R is composed of a roller-shaped first support rotating body. This first support rotating body 19 is integral with the scribing cutter 17 and moves in the direction of arrow E (from one end R1 side towards the other end R2 side in the width direction of the glass strip R). Furthermore, the scribing apparatus 15 includes a coating roller 52 that moves ahead of the scribing cutter 17 on the back side Rb of the glass strip R at the same speed in the direction of arrow E. The coating roller 52 coats the back side Rb of the glass strip R with liquids such as ethanol and methanol. In addition, the scribing apparatus 15 includes a second support rotating body 53 that supports the coating roller 52 from the surface Ra side of the glass strip R. This second support rotating body 53 is integral with the coating roller 52 and moves in the direction of arrow E. When the scribing device 15 with this structure forms a scribing line S on the glass strip R, wrinkles Rp may also be generated in the region on the side of the end S2 of the scribing line S in the glass strip R, just as in the case described above.

[0220] In the above embodiments, the present invention is applied to an apparatus and method for manufacturing glass plates using the overflow down-draw method, but the present invention can also be applied to an apparatus and method for manufacturing glass plates using other methods such as the slit down-draw method.

[0221] In the above embodiment, when the glass strip R is broken by the breaking device 16, bending stress is applied to the glass strip R while the broken body 22 is in contact with the glass strip R. However, the broken body 22 can also touch the glass strip R while bending stress is applied to the glass strip R.

[0222] In the above embodiment, when the glass strip R is broken by the breaking device 16, the broken body 22 is brought into contact with the position where the scribe line S of the glass strip R is formed, but the broken body 22 may also be brought into contact with a position on the glass strip R above the scribe line S (including the above-mentioned contact).

[0223] In the above embodiment, a limiting roller 46 is used as a limiting member to restrict the oscillation of the glass strip R, but the limiting member may not be roller-shaped, for example, it may be a sphere that rotates in the same way as the limiting roller 46.

[0224] In the above embodiment, the limiting rollers 46 clamp the glass strip R from both sides in the direction of the back of the glass strip, thereby limiting the swing of the glass strip R. However, the limiting rollers 46 may not clamp the glass strip R. That is, the limiting rollers 46 may be configured such that the gap between the pairs of limiting rollers 46 is larger than the thickness of the glass strip R, and the glass strip R only contacts the limiting rollers 46 when the glass strip R swings.

[0225] In the above embodiment, the beginning S1 and the end S2 of the scribe line S are located on the glass strip R at a position closer to the center of the width direction than the first contact mark 41. However, the beginning S1 and the end S2 of the scribe line S can also be located within the first contact mark 41 or within the striped gap region 43. However, the beginning S1 and the end S2 of the scribe line S are preferably located on the glass strip R at a position closer to the center of the width direction than the ear portion Rm.

[0226] In the above embodiment (first embodiment), the measuring roller 13 is integrally mounted on the first roller shaft 30, but the first roller shaft 30 can also be fixedly set and the measuring roller 13 can be rotatably mounted on the first roller shaft 30.

[0227] In the above embodiment (first embodiment), the measuring roller 13 is cantilevered, but the measuring roller 13 can also be mounted on the first roller shaft 30, which is supported at both ends in the width direction. The same applies to the auxiliary roller 14.

[0228] In the above-described embodiment (second embodiment), two sensors 50 are arranged at different positions in the vertical direction, but three or more sensors 50 can also be arranged at different positions in the vertical direction. In this case, two sensors 50 are actually used, and if, for example, any of the sensors 50 in use fails or becomes unusable due to its lifespan, it can be switched to another sensor 50. Therefore, the measurement of the glass strip R's moving speed can continue without interruption. Furthermore, in this case, multiple moving speeds can be calculated using signals from three or more sensors 50, and the moving speed of the components of the cutting device 5 can be made to follow the moving speed of one of them. The remaining calculated moving speeds are used to confirm whether the aforementioned moving speed is accurate.

Claims

1. A glass sheet manufacturing apparatus comprising: a forming device for forming a glass ribbon from molten glass; a conveying device for conveying the glass ribbon in a downward direction; a speed measuring device for measuring the moving speed of the glass ribbon being conveyed downward by the conveying device; and a cutting device for cutting single-sheet glass sheets from the glass ribbon. The glass plate manufacturing apparatus is characterized in that, The cutting device includes: a scribing device that forms a scribing line extending along the width direction of the glass strip from one end side of the glass strip in a width direction orthogonal to the other end side; and a breaking device that breaks the glass strip at the location where the scribing line is formed to obtain a single sheet of glass. The speed measuring device measures the moving speed of the region on one side of the glass strip that is closer to the center in the width direction.

2. The glass plate manufacturing apparatus according to claim 1, wherein, The forming apparatus further comprises: a forming body that forms the glass ribbon from the molten glass; and edge rollers that clamp and convey the glass ribbon downward in the width direction from both ends of the glass ribbon descending from the forming body. The speed measuring device measures the moving speed of the region in the glass belt that is in contact with the edge roller and is located on the central side in the width direction.

3. The glass plate manufacturing apparatus according to claim 1, wherein, The glass strip has ears at both ends in the width direction that are thicker than the central portion in the width direction. The speed measuring device measures the movement speed of the region in the glass strip that is closer to the center side in the width direction than the ear.

4. The apparatus for manufacturing a glass plate according to any one of claims 1 to 3, wherein, The speed measuring device includes a measuring roller that rotates in contact with the glass strip, and measures the moving speed of the glass strip based on the rotational speed of the measuring roller.

5. The glass plate manufacturing apparatus according to claim 4, wherein, The measuring roller is a free roller.

6. The glass plate manufacturing apparatus according to claim 2, wherein, The glass sheet manufacturing apparatus further includes an annealing furnace below the formed body for annealing the glass strip. The conveying device includes annealing rollers for conveying the glass ribbon within the annealing furnace. The annealing roller clamps the region of the glass ribbon that is closer to the center side in the width direction than the contact portion that contacts the edge roller. The speed measuring device measures the moving speed of the area in the glass belt other than the contact portion that contacts the annealing roller.

7. The glass plate manufacturing apparatus according to claim 6, wherein, The speed measuring device measures the moving speed of the region in the glass belt that is in contact with the annealing roller and is located on the central side in the width direction.

8. The glass plate manufacturing apparatus according to claim 6, wherein, The glass sheet manufacturing apparatus also includes a cooling chamber below the annealing furnace for cooling the glass strip. The conveying device includes support rollers that support the glass strip in the cooling chamber. The support roller clamps the region of the glass strip that is closer to the center side in the width direction than the contact portion that contacts the edge roller. The speed measuring device measures the moving speed of the area in the glass belt other than the contact portion that contacts the support roller.

9. The glass plate manufacturing apparatus according to claim 8, wherein, The speed measuring device measures the moving speed of the region in the glass belt that is in contact with the support roller and is located on the central side in the width direction.

10. The apparatus for manufacturing a glass plate according to any one of claims 1 to 3, wherein, The glass strip has an effective region located at the center side in the width direction and a non-effective region comprising the entire region located at the ends in the width direction beyond the effective region. The speed measuring device measures the movement speed of the non-effective area.

11. The glass plate manufacturing apparatus according to claim 4, wherein, The speed measuring device includes an auxiliary roller disposed at a position corresponding to the measuring roller, separated from the glass belt.

12. The glass plate manufacturing apparatus according to claim 11, wherein, The auxiliary roller is a drive roller.

13. The glass plate manufacturing apparatus according to claim 12, wherein, The rotational speed of the auxiliary roller is controlled in such a way that it follows the moving speed of the glass ribbon as measured by the measuring roller.

14. The glass plate manufacturing apparatus according to claim 11, wherein, The measuring roller is disposed on one side of the glass strip, and the auxiliary roller is disposed on the other side of the glass strip. Pressure is applied to the measuring roller from the auxiliary roller via the glass strip.

15. The glass plate manufacturing apparatus according to claim 14, wherein, The scribing apparatus includes: a scribing tool that forms the scribing line on the other side of the glass strip; and a support body that contacts the other side of the glass strip when the scribing tool forms the scribing line and supports the glass strip.

16. The glass plate manufacturing apparatus according to claim 1 or 2, wherein, A guide roller for holding the glass strip is provided in a region on the other end side of the glass strip at a height position corresponding to the speed measuring device, which is located at the center of the glass strip in the width direction.

17. The glass plate manufacturing apparatus according to claim 4, wherein, At least the outer periphery of the measuring roller is formed of heat-resistant rubber.

18. The glass plate manufacturing apparatus according to claim 1 or 2, wherein, The speed measuring device measures the moving speed of the glass strip in the area below the conveying device and above the scribing device.

19. The glass plate manufacturing apparatus according to claim 18, wherein, The glass plate manufacturing apparatus has a limiting member in the area below the speed measuring device and above the scribing device to restrict the oscillation of the glass strip.

20. The apparatus for manufacturing a glass plate according to any one of claims 1 to 3, wherein, The speed measuring device measures the moving speed of the glass strip in a non-contact manner.

21. The glass plate manufacturing apparatus according to claim 20, wherein, The speed measuring device includes multiple sensors disposed below the position where the breaking device breaks the glass ribbon, and capable of detecting the presence or absence of the glass ribbon. The multiple sensors are disposed at different positions in the vertical direction. The speed measuring device uses the plurality of sensors to detect the time when the lower end face of the glass strip formed by the breaking device is positioned and the vertical distance between the plurality of sensors, and calculates the moving speed of the glass strip.

22. The glass plate manufacturing apparatus according to claim 20, wherein, The cutting device moves downwards in accordance with the moving speed of the glass strip as determined by the speed measuring device.

23. A method for manufacturing a glass plate, comprising: The forming process involves shaping molten glass into glass ribbons. The process includes a conveying step, in which the glass strip is conveyed downwards; a speed measurement step, in which the moving speed of the glass strip is measured during the conveying step; and a cutting step, in which single-sheet glass plates are cut from the glass strip. The method for manufacturing the glass plate is characterized in that, The cutting process includes: a scribing process, forming a scribing line extending along the width direction of the glass strip from one end side of the glass strip towards the other end side in a width direction orthogonal to the transport direction; and a breaking process, breaking the glass strip at the location where the scribing line was formed to obtain a single sheet of glass. In the speed measurement process, the moving speed of the region on one end side of the glass strip that is closer to the center in the width direction is measured.

Images