Glass sheet manufacturing method and manufacturing device thereof

Abstract

After forming a scribe line 3 along a widthwise direction on a glass ribbon 2 that moves down in a longitudinal posture, a planned cutout portion 2x is cut out as a glass plate by bending and braking off the glass ribbon 2 along the scribe line 3 in a state in which the planned cutout portion 2x located below the scribe line 3 of the glass ribbon 2 is supported by a support means 4, wherein the glass ribbon 2 is bent and broken off by pressing a bending and breaking bar 5 against a scribe line formed region 2s in a state in which the scribe line formed region 2s of the glass ribbon 2 is curved in a longitudinal direction by operating the support means 4.

Description

[Technical field]

[0001] The present invention relates to a method and apparatus for manufacturing a glass sheet, in which a scribe line is formed along the width direction of a glass ribbon moving downward in a vertical position, and a glass sheet is cut from the glass ribbon by bending and breaking the glass ribbon along the scribe line. [Background technology]

[0002] As is well known, in the field of glass sheet production, glass sheets are cut out from a glass ribbon that is formed by a down-draw method and moves downward. A specific example of a method and apparatus for producing glass sheets in this manner is disclosed in Patent Document 1.

[0003] The device disclosed in the document includes a scribing means for forming a scribe line on a glass ribbon moving downward in a vertical position, a breaking bar (called a fulcrum bar in the document) that is pressed against a scribe line formation area of ​​the glass ribbon, and a support means (called a breaking arm in the document) that supports a planned cutting-out portion of the glass ribbon. The method disclosed in the document for cutting out a glass sheet using this device involves first forming a scribe line along the width direction of the glass ribbon with the scribing means, and then pressing the breaking bar against the scribe line formation area of ​​the glass ribbon. Next, the support means that is in a state of supporting the planned cutting-out portion of the glass ribbon is operated to bend the scribe line formation area with the breaking bar as a fulcrum. As a result, the glass ribbon is broken along the scribe line, and a glass sheet is cut out from the glass ribbon. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-90446 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, as disclosed in Patent Document 1, in a configuration in which after a scribe line is formed in a glass ribbon, a breaking bar is first pressed against the scribe line formation area, and then the scribe line formation area is bent using the breaking bar as a fulcrum to break the glass ribbon, the following problems arise.

[0006] That is, the glass ribbon moving downward in a vertical position usually has warping or distortion (hereinafter, simply referred to as "warping") due to the influence of heat during forming, for example, thermal stress during annealing. This warping occurs not only along the longitudinal direction (vertical direction) of the glass ribbon, but also along the width direction perpendicular to the longitudinal direction. This warping of the glass ribbon remains even after the scribe line is formed. Therefore, when the breaking bar is pressed against the scribe line formation region of the glass ribbon, the breaking bar comes into local contact with the scribe line formation region. In this state, if the scribe line formation region is curved with the breaking bar as a fulcrum, there is a risk of breaking errors, such as the glass ribbon being broken at a position deviated from the scribe line or the glass ribbon cracking starting from the contact point with the breaking bar.

[0007] Furthermore, in order to break the glass ribbon while taking such breaking errors into consideration, it is necessary to slow down the operating speed of the supporting means for curving the scribe line formation region, which may result in a longer tact time when breaking the glass ribbon, leading to a deterioration in work efficiency.

[0008] In view of the above, an object of the present invention is to prevent cutting errors when bending and breaking a glass ribbon using a breaking bar, and to shorten the tact time, thereby improving the quality of the cut glass sheets and improving work efficiency. [Means for solving the problem]

[0009] A first aspect of the present invention, which has been devised to solve the above-mentioned problems, is a method for manufacturing a glass plate, including a scribing step of forming a scribe line along the width direction of a glass ribbon moving downward in a vertical position, and a bending and splitting step of bending and splitting the glass ribbon along the scribe line while a portion of the glass ribbon to be cut out that is below the scribe line is supported by a supporting means, and cutting out the portion to be cut out as a glass plate, wherein the bending and splitting step is characterized in that the glass ribbon is bent and split by pressing a bending bar against the area of ​​the scribe line while the supporting means is operated to bend the area of ​​the glass ribbon where the scribe line is formed in the vertical direction.

[0010] According to this method, even if the glass ribbon moving downward in a vertical position has warpage along the longitudinal direction (vertical direction) or the width direction perpendicular thereto, the glass ribbon can be appropriately bent and broken without being adversely affected by the warpage. More specifically, in this method, in the breaking step after the scribing step, the scribe line formation region of the glass ribbon (hereinafter referred to as the scribe line formation region) is first curved in the vertical direction, and the warpage naturally disappears due to the curved deformation that is forcibly generated in the region at this time. Next, by pressing the breaking bar against the curved scribe line formation region in a state where the warpage has disappeared, the breaking bar comes into contact with the region evenly without locally contacting it. Then, the glass ribbon is broken while maintaining an even contact state with the breaking bar, so that breaking errors are unlikely to occur. Furthermore, since the need to consider breaking errors when breaking is reduced, it becomes possible to operate the support means at high speed, and the tact time can be shortened. As a result of the above, the quality of the cut glass sheet and the working efficiency are improved.

[0011] In this method, the breaking bar may be pressed against the scribe line formation region after the operation of the supporting means is completed.

[0012] In this way, it becomes possible to appropriately deal with shaking or the like of the glass ribbon. That is, while the supporting means is operating in a state where it supports the glass ribbon, shaking or the like occurs in the glass ribbon, making it difficult to perform proper bending or breaking. According to the configuration here, shaking or the like that occurs in the glass ribbon is reduced as the operation of the supporting means ends. In this state, the bending or breaking bar is pressed against the scribe line formation region to bend or break the glass ribbon, so that breaking errors are more reliably prevented.

[0013] Alternatively to the configuration of this method, the breaking bar may be pressed against the scribe line forming region during the operation of the supporting means.

[0014] In this way, the support means continues to operate even after the glass ribbon is broken. Therefore, after the glass ribbon is broken, the cut glass sheet and the glass ribbon supported by the support means that continues to operate are instantly separated from each other. This avoids problems such as the glass sheet and the glass ribbon being damaged due to inappropriate contact between them. Moreover, there is no waste in the time until the glass ribbon is broken, which makes it possible to further shorten the takt time and smoothly carry out the transport process of the glass sheet after the glass ribbon is broken.

[0015] In the above-described method, the supporting means may be temporarily stopped during operation, the bending bar may be pressed against the scribe line formation region, and then the supporting means may be operated again.

[0016] In this way, the shaking of the glass ribbon is reduced while the operation of the supporting means is temporarily stopped. Therefore, the breaking bar can be pressed against the scribe line formation region of the glass ribbon in a state where the shaking is reduced, and breaking errors can be more reliably prevented, as in the above-mentioned case.

[0017] Alternatively to the configuration of this method, the supporting means may be moved at a relatively high speed and then at a relatively low speed, and thereafter the breaking bar may be pressed against the scribe line forming area.

[0018] In this way, the operating speed of the supporting means becomes relatively slow in the latter half of the operation, so that the shaking of the glass ribbon is reduced, and the breaking bar can be pressed against the scribe line formation area in this state. Therefore, in this case, as in the case described above, it is possible to further prevent breaking errors when breaking the glass ribbon. In this case, the operation of the supporting means is not stopped until the breaking is performed, so that it is possible to prevent the tact time from becoming longer. Therefore, according to the configuration here, it is possible to more reliably achieve both prevention of breaking errors and shortening of the tact time. Note that when the supporting means is operated at a relatively slow speed, the breaking bar may be pressed against the scribe line formation area after the operation is completed, or the breaking bar may be pressed against the scribe line formation area while the supporting means is being operated at a relatively slow speed.

[0019] In the above method, the breaking bar may be pressed against a portion above the scribe line in the glass ribbon formation region.

[0020] In this way, when the glass ribbon is broken along the scribe line, the breaking bar is pressed against a portion above the scribe line, so that the pressing position of the breaking bar and the formation position of the scribe line are separated in the vertical direction, which reduces the probability that a crack will propagate vertically starting from the scribe line, and thus the glass may be less likely to break or be damaged.

[0021] In this method, the breaking bar may be pressed against a portion of the glass ribbon that is 5 mm or more and less than 70 mm above the scribe line, or the breaking bar may be pressed against a portion of the glass ribbon that is 5 mm or more above the scribe line and less than the lower end of the effective area. Here, the effective area of ​​the glass ribbon refers to an area that becomes a glass sheet product after bending and breaking. In detail, the glass ribbon has an unnecessary area that is cut and removed after bending and an effective area that is not removed.

[0022] In the above method, the pressing side end of the breaking bar, which has a curved shape along the width direction that is convex on one side, may be pressed against the scribe line formation area, which has a curved shape along the width direction that is convex on the same side as the scribe line formation area.

[0023] In this way, when bending and breaking the glass ribbon along the scribe lines, even if the warp along the width direction perpendicular to the longitudinal direction does not completely disappear, it is possible to appropriately deal with the situation. That is, when bending and breaking a glass ribbon having a curved shape along the width direction that is convex on one side, a bending and breaking bar having a pressing side end portion having a curved shape along the width direction that is convex on the same side as the glass ribbon is used. Therefore, it is possible to prevent the occurrence of cracks or breaking errors when bending and breaking a glass ribbon that is curved in the width direction using a bending and breaking bar having a pressing side end portion that is shaped to be aligned in a straight line in the width direction.

[0024] A second aspect of the present invention, which was devised to solve the above-mentioned problems, is a glass plate manufacturing apparatus comprising: a scribing means for forming a scribe line along the width direction of a glass ribbon moving downward in a vertical position; a support means for supporting a portion of the glass ribbon to be cut out below the scribe line; a breaking bar pressed against the formation area of ​​the scribe line of the glass ribbon; and a control means for controlling each operation of the support means and the breaking bar in order to bend and break the glass ribbon along the scribe line and cut out the portion to be cut out as a glass plate, wherein the control means controls each operation of the support means and the breaking bar so that, when bending and breaking the glass ribbon, the formation area of ​​the scribe line is curved in the vertical direction, and the breaking bar can be pressed against the formation area of ​​the scribe line.

[0025] According to this manufacturing device, when breaking the glass ribbon, the control means controls the operations of the support means and the breaking bar, so that the breaking bar can be pressed against the scribe line formation area in a curved state. Therefore, with this manufacturing device, as with the manufacturing method described above, breaking errors can be prevented and the takt time can be shortened. Effect of the Invention

[0026] According to the present invention, it is possible to prevent cutting errors when breaking a glass ribbon using a breaking bar, and it is also possible to shorten the tact time, thereby improving the quality of the cut glass sheets and improving the work efficiency. [Brief description of the drawings]

[0027] [Figure 1] 1 is a front view showing a schematic configuration of a glass sheet manufacturing apparatus according to an embodiment of the present invention. [Diagram 2] 1 is a front view showing a schematic configuration of a glass plate manufacturing apparatus according to an embodiment of the present invention (a front view seen along the arrow X in FIG. 1). [Diagram 3]FIG. 2 is a schematic side view showing a state in which the method for producing a glass plate according to the embodiment of the present invention is carried out. [Figure 4] FIG. 2 is a schematic side view showing a state in which the method for producing a glass plate according to the embodiment of the present invention is carried out. [Diagram 5] FIG. 2 is a schematic side view showing a state in which the method for producing a glass plate according to the embodiment of the present invention is carried out. [Figure 6] FIG. 2 is a schematic side view showing a state in which the method for producing a glass plate according to the embodiment of the present invention is carried out. [Figure 7] FIG. 1 is a schematic side view showing an implementation state of a method for producing a glass plate according to an embodiment of the present invention (a first modified example of the implementation state). [Figure 8] FIG. 2 is a schematic side view showing an implementation state of the method for producing a glass plate according to the embodiment of the present invention (a second modified example of the implementation state). [Figure 9] FIG. 2 is a schematic side view showing an implementation state of the method for producing a glass plate according to an embodiment of the present invention (a third modified example of the implementation state). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Hereinafter, a method and an apparatus for producing a glass sheet according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0029] FIG. 1 is a side view illustrating a manufacturing apparatus for a glass sheet according to an embodiment of the present invention, and FIG. 2 is a front view of the manufacturing apparatus as viewed along the arrow X in FIG. 1. As shown in these figures, the manufacturing apparatus 1 includes a scribing means S for forming a scribe line 3 along the width direction of a glass ribbon 2 moving downward in the direction of the arrow Z in a vertical posture, a supporting means 4 for supporting a portion to be cut out 2x located below the scribe line 3 of the glass ribbon 2, and a breaking bar 5 pressed against a scribe line formation region 2s of the glass ribbon 2. Furthermore, the manufacturing apparatus 1 includes a control means 6 for controlling each operation of the supporting means 4 and the breaking bar 5 in order to break the glass ribbon 2 along the scribe line 3 and cut out the portion to be cut out 2x as a glass sheet. In detail, the control means 6 controls each operation of the supporting means 4 and the breaking bar 5 so that, when breaking the glass ribbon 2, the bending bar 5 can be pressed against the scribe line formation region 2s in a state in which the scribe line formation region 2s is curved as shown by a solid line in FIG. 1.

[0030] The scribing means S includes a wheel cutter 7 that forms a scribe line 3 while traveling along the width direction (in FIG. 1, a direction perpendicular to the paper surface) on the front surface 2a of the downwardly moving glass ribbon 2, and a support rod 8 that is long in the width direction and supports the portion of the glass ribbon 2 along which the wheel cutter 7 travels from the rear surface 2b side. The wheel cutter 7 has a blade (edge) on the periphery that rotates during travel, and is formed in a disk shape. The support rod 8 has an abutment surface that abuts against the portion along which the wheel cutter 7 travels, and protrudes from both ends of the glass ribbon 2 in the width direction.

[0031] The breaking bar 5 is pressed against the back surface 2b of the scribe line formation region 2s, and has a pressing side end portion 5a having a convex shape (e.g., semicircular or curved shape) in vertical cross section that abuts against the scribe line formation region 2s. The pressing side end portion 5a is formed to extend linearly along the width direction, and protrudes from both ends of the glass ribbon 2 in the width direction. Here, the back surface 2b of the scribe line formation region 2s against which the breaking bar 5 is pressed is, strictly speaking, a back surface portion including the scribe line 3 and including a straight line where an imaginary plane along the thickness direction of the glass ribbon 2 intersects with the back surface 2b of the glass ribbon 2. The scribe line formation region 2s is a region between portions of the glass ribbon 2 that are 80 to 120 mm above and below the scribe line 3.

[0032] A suction nozzle 9 for suctioning glass powder generated during breaking is disposed at a position facing the breaking bar 5 across the glass ribbon 2. The suction nozzle 9 has an opening 9a facing the surface 2a of the glass ribbon 2, and sucks up the glass powder through the opening 9a by the operation of a negative pressure generating device (not shown) such as a negative pressure pump.

[0033] The support means 4 includes an arm 10 extending along the longitudinal direction of the glass ribbon 2, and a chuck group 11 including a plurality of chucks 11a (five in this embodiment) attached to the arm 10 at intervals from each other. The arm 10 and the chuck group 11 are disposed on one side and the other side in the width direction of the glass ribbon 2. Each of the plurality of chucks 11a includes a pair of claws 11ax that grip the portion 2x of the glass ribbon 2 to be cut out in the thickness direction.

[0034] Furthermore, the support means 4 is configured to change its posture from a basic posture shown by a chain line in FIG. 1 to an inclined posture shown by a solid line in the same figure while supporting the to-be-cut-out portion 2x. This change in posture of the support means 4 is achieved by a rotational movement of the support means 4 about the position of the cleaving bar 5 (the position shown by the solid line in FIG. 1). Furthermore, the change in posture of the support means 4 is achieved while moving downward at the same speed as the glass ribbon 2. Then, the support means 4 curves the scribe line formation region 2s in the vertical direction so that the front surface 2a side becomes convex by the above-mentioned rotational movement. Such a rotational movement of the support means 4 plays a role of folding and splitting the glass ribbon 2 along the scribe line 3 in cooperation with the movement of pressing the cleaving bar 5 against the scribe line formation region 2s. Then, the rotational movement of the support means 4 and the movement of pressing the cleaving bar 5 when folding and splitting are controlled by the control means 6 in a timed manner.

[0035] In this embodiment, the arm 10 and the chuck group 11 arranged on one side in the width direction of the glass ribbon 2, and the arm 10 and the chuck group 11 arranged on the other side in the width direction of the glass ribbon 2 are configured to rotate as a unit. However, the arms 10 and the chuck groups 11 on both sides may each rotate individually, and in that case, the control means 6 controls the arms 10 and the chuck groups 11 on both sides to rotate in a synchronized manner.

[0036] Among the components of the manufacturing apparatus 1, the breaking bar 5 and the support rod 8 are mounted on a first housing (not shown) arranged on the back surface 2b side of the glass ribbon 2, and the wheel cutter 7 and the suction nozzle 9 are mounted on a second housing (not shown) arranged on the front surface 2a side of the glass ribbon 2. The first housing and the second housing are each capable of moving in the vertical direction. As a result, the breaking bar 5 and the support rod 8 are configured to move up and down integrally with the first housing while maintaining their relative positional relationship in the vertical direction. In addition, the wheel cutter 7 and the suction nozzle 9 are configured to move up and down integrally with the second housing while maintaining their relative positional relationship in the vertical direction.

[0037] Each of the first housing and the second housing can move downward following the glass ribbon 2 at the same speed as the downward movement speed of the glass ribbon 2. As a result, each of the breaking bar 5, the support rod 8, the wheel cutter 7, and the suction nozzle 9 is configured to move downward at the same speed as the downward movement speed of the glass ribbon 2 along with the downward movement of the first housing and the second housing following the glass ribbon 2, thereby performing its own function. Similarly, the support means 4 is also configured to move downward at the same speed as the downward movement speed of the glass ribbon 2, while performing its own function. Therefore, when each of the above-mentioned components of the manufacturing apparatus 1 performs its own function, the relative speed in the vertical direction with respect to the glass ribbon 2 is zero.

[0038] Of the above components, the breaking bar 5, the support rod 8, the wheel cutter 7, and the suction nozzle 9 are configured to move along the thickness direction of the glass ribbon 2 between an operating position for performing their own functions and a retracted position for retracting away from the glass ribbon 2, as shown by the arrows in Fig. 1. The movement of each of these components along the thickness direction is performed while moving downward at the same speed as the glass ribbon 2. The breaking bar 5 and the suction nozzle 9 are in the operating position shown by the solid line in Fig. 1, and are in the retracted position shown by the dashed line in Fig. 1. On the other hand, the wheel cutter 7 and the support rod 8 are in the operating position shown by the dashed line in Fig. 1, and are in the retracted position shown by the solid line in Fig. 1.

[0039] If necessary, in order to regulate the shaking of the glass ribbon 2 during the cleaving step, a pair of free rollers (regulating rollers) may be provided between the scribing means S and the cleaving bar 5. The pair of free rollers is mounted on the first housing and the second housing, respectively, and configured to move along the thickness direction of the glass ribbon 2 between an operating position and a retracted position.

[0040] Note that above the scribing means S, multiple pairs of rollers 12 (only two pairs of rollers 12 are shown in FIG. 1) that hold the glass ribbon 2 are arranged vertically with a gap between them. These rollers 12 are annealer rollers in an annealing furnace, support rollers located below the annealing furnace, etc.

[0041] Next, a method for producing a glass plate using the above-mentioned production apparatus 1 will be described with reference to FIGS.

[0042] In the method for manufacturing a glass sheet according to the present embodiment, the glass ribbon 2 to be broken is formed, for example, by a down-draw method (such as an overflow down-draw method). The glass ribbon 2 is formed to a thickness of, for example, 1000 μm or less (preferably 700 μm or less and 250 μm or more), and has flexibility that allows it to be curved by the action of an external force.

[0043] The method for manufacturing a glass plate according to this embodiment broadly comprises a scribing process for forming a scribe line 3 in a glass ribbon 2, and a bending and splitting process for bending and splitting the glass ribbon 2 along the scribe line 3 formed in the scribing process to cut out a glass plate.

[0044] 3, in the scribing step, first, the wheel cutter 7 and the support rod 8 are moved from the retracted position to the operating position while the multiple chucks 11a of the support means 4 support the portion to be cut out 2x. Next, the wheel cutter 7 that has been moved to the operating position is caused to run on the surface 2a of the glass ribbon 2 in the width direction to form a scribe line 3.

[0045] After the scribing step is completed as described above, the wheel cutter 7 and the support rod 8 are moved from the operating position to the retreated position. In this case, the support of the to-be-cut-out portion 2x by the multiple chucks 11a of the support means 4 is continued even after the scribing step is completed. Here, when the scribing step is completed, the wheel cutter 7 and the support rod 8 are in a state of being at the same height position as the scribe line 3. From this state, in preparation for performing the folding step, both the first housing and the second housing move upward relative to the glass ribbon 2. As a result, as shown in FIG. 4, instead of the wheel cutter 7 and the support rod 8, the folding bar 5 and the suction nozzle 9 are held at the same height position as the scribe line 3. When a regulating roller is used, the regulating roller is moved from the retreated position to the operating position.

[0046] In the folding step, as shown in FIG. 5, the supporting means 4 is rotated as indicated by the arrow C while the folding bar 5 and the suction nozzle 9 are held in the retreated position. As a result, the posture of the supporting means 4 changes from the basic posture to an inclined posture, and the scribe line formation region 2s of the glass ribbon 2 is curved in the vertical direction so that the front surface 2a side is convex. At this time, the portion of the glass ribbon 2 above the scribe line formation region 2s is clamped by a plurality of pairs of rollers 12, and is further clamped by a regulating roller as necessary. Therefore, the operation of curving the scribe line formation region 2s in the vertical direction is performed appropriately. Then, when the angle α of the supporting means 4 with respect to the vertical line reaches a preset inclination angle, that is, when the curvature of the scribe line formation region 2s increases to a predetermined curvature, the rotating operation of the supporting means 4 is stopped. Here, the timing for stopping the rotating operation of the supporting means 4 is preset, and the control means 6 performs control to stop the rotating operation of the supporting means 4 based on the setting.

[0047] After the rotation of the support means 4 is completed as described above, the cleavage bar 5 and the suction nozzle 9 are moved from the retreated position to the operating position. As a result, the cleavage bar 5 is pressed against the back surface 2b of the scribe line formation region 2s, which is in a curved state, as shown in FIG. 6. By such an operation, the glass ribbon 2 is broken along the scribe line 3, and the portion to be cut out 2x is cut out as a glass plate 2y. Glass powder generated by this folding is sucked by the suction nozzle 9. Here, the timing at which the cleavage bar 5 is pressed against the scribe line formation region 2s is preset in relation to the rotation of the support means 4, and the control means 6 performs control to press the cleavage bar 5 against the scribe line formation region 2s based on the setting.

[0048] In this embodiment, the above-described bending and splitting process is performed, thereby obtaining the following effects. That is, the glass ribbon 2 moving downward in a vertical position is warped due to, for example, thermal stress or contact with the roller 12. This warp occurs not only along the longitudinal direction of the glass ribbon 2 but also along the width direction perpendicular to the longitudinal direction. This warp of the glass ribbon 2 remains even after the scribe line 3 is formed on the glass ribbon 2 in the scribing process. However, in the above-described breaking process, the scribe line formation region 2s of the glass ribbon 2 is first curved in the longitudinal direction, and the warp naturally disappears due to the curved deformation forcibly generated in the scribe line formation region 2s at this time. Next, the bending and splitting bar 5 is pressed against the curved scribe line formation region 2s in a state where the warp has disappeared, so that the bending and splitting bar 5 comes into even contact with the scribe line formation region 2s. After this, the glass ribbon 2 is bent and split while maintaining an even contact state with the bending and splitting bar 5, thereby preventing breaking errors. Furthermore, since the need to consider cleavage errors when performing cleavage is reduced, it is possible to rotate the support means 4 at high speed, and the tact time can be shortened. As a result of the above, the quality of the glass sheet cut out from the glass ribbon 2 is improved and the work efficiency is improved. Furthermore, according to the above cleavage process, it is possible to appropriately deal with the shaking of the glass ribbon 2. That is, while the support means 4 is rotating while supporting the glass ribbon 2, the glass ribbon 2 is shaken, making it difficult to perform proper cleavage. However, in the above cleavage process, the shaking of the glass ribbon 2 is reduced as the rotation of the support means 4 is completed, and the cleavage bar 5 is pressed against the scribe line formation region 2s in which the shaking is reduced and the cleavage is in a stable state. This more reliably prevents cleavage errors during cleavage.

[0049] In the above embodiment, in the bending and breaking step, after the rotation of the support means 4 is completed, the bending and breaking bar 5 is pressed against the scribe line formation region 2s. Instead of this, the following configuration can be adopted. That is, after the bending and breaking bar 5 is pressed against the scribe line formation region 2s to bend and break the glass ribbon 2, the support means 4 is configured to continue to rotate as shown in FIG. 7. In other words, the bending and breaking bar 5 is configured to be pressed against the scribe line formation region 2s while the support means 4 is being rotated. In this way, as shown in the figure, the glass ribbon 2 and the cut glass sheet 2y are instantly separated from each other immediately after bending and breaking, so that problems such as breakage due to inappropriate contact between them are unlikely to occur. Moreover, there is no waste in the time until the bending and breaking of the glass ribbon 2 is completed, which makes it possible to further shorten the tact time and smoothly carry out the transport process of the glass sheet 2y after bending and breaking.

[0050] In the above embodiment, the rotation of the support means 4 is performed continuously at a constant speed from the start of the operation to the end of the operation. Instead of this, the following configuration can be adopted. That is, the rotation of the support means 4 is temporarily stopped between the start of the rotation and the time when the support means 4 assumes the inclined posture for folding and splitting. In detail, as shown in FIG. 8, the rotation of the support means 4 is temporarily stopped when the support means 4 assumes the inclined posture indicated by the chain line (posture inclined by angle α1 with respect to the vertical line) during the rotation of the support means 4. Thereafter, the support means 4 is rotated again, and when the support means 4 assumes the inclined posture indicated by the solid line in the figure (posture inclined by angle (α1+α2) with respect to the vertical line), the folding bar 5 is pressed against the scribe line formation region 2s to perform folding and splitting. In this case, the angle α1 shown in the figure is larger than the angle α2. Therefore, the time from the start of the rotation of the support means 4 to the time when it is temporarily stopped is longer than the time from the time when the support means 4 is temporarily stopped to the time when it assumes the inclined posture for folding and splitting. In other words, the moving distance of the supporting means 4 along the circular orbit before the support means 4 is temporarily stopped is longer than the moving distance of the supporting means 4 along the circular orbit after the support means 4 is temporarily stopped. The timing for temporarily stopping the rotational operation of the supporting means 4 and the timing for restarting the rotational operation are preset, and the control means 6 controls the rotational operation of the supporting means 4 based on these settings. With this configuration, the shaking of the glass ribbon 2 is reduced while the rotational operation of the supporting means 4 is temporarily stopped. Therefore, as in the above-mentioned case, the breaking bar 5 can be pressed against the scribe line formation region 2s in which the shaking is reduced and which is in a stable state, and the breaking error during the breaking can be more reliably prevented. When the supporting means 4 is rotated again, the breaking bar 5 may be pressed against the scribe line formation region 2s after the rotational operation is completed, or the breaking bar 5 may be pressed against the scribe line formation region 2s while the supporting means 4 is being rotated again.

[0051] Further, here, when the supporting means 4 assumes the inclined posture shown by the chain line in FIG. 8, the rotation of the supporting means 4 is temporarily stopped. Instead, the following configuration can be adopted. That is, the supporting means 4 is rotated at a relatively high speed from when the supporting means 4 starts to rotate until it assumes the inclined posture shown by the chain line in FIG. 8, and after the supporting means 4 assumes the inclined posture, the supporting means 4 is rotated at a relatively low speed. In this case, the relationship between the speed T1 when the supporting means 4 is rotated at a relatively low speed and the speed T2 when the supporting means 4 is rotated at a relatively high speed is T1 / T2, which is 1 / 5 or more and 3 / 5 or less (preferably 1 / 4 or more and 1 / 2 or less). Also, the angle α1 of the supporting means 4 with respect to the vertical line at the time when the relatively high speed rotation ends is larger than the angle α2 of the supporting means 4 rotating from when the relatively low speed rotation starts until the folding and splitting is performed. In other words, the moving distance of the supporting means 4 along the circular orbit when rotating at a relatively high speed is longer than the moving distance of the supporting means 4 along the circular orbit when rotating at a relatively low speed. The switching timing of each operation speed of the supporting means 4 and the value of each operation speed are set in advance, and the control means 6 controls the operation speed of the supporting means 4 based on these settings. According to the above-mentioned configuration, the operation speed of the supporting means 4 becomes relatively slow in the latter half of the operation, thereby reducing the shaking of the glass ribbon 2, and the glass ribbon 2 can be broken by maintaining this state. In this case, since the operation of the supporting means 4 is not stopped, it is possible to prevent the tact time from becoming long. Therefore, according to the configuration here, it is possible to more reliably achieve both the prevention of breaking errors and the shortening of the tact time. In addition, when the support means 4 is operated at a relatively slow speed, the crease bar 5 may be pressed against the scribe line formation area 2s after the operation is completed, or the crease bar 5 may be pressed against the scribe line formation area 2s while the support means 4 is being operated at a relatively slow speed.

[0052] In the above embodiment, the cleaving bar 5 is moved in the horizontal direction, but it may be moved in the thickness direction of the curved scribe line formation region 2s (a direction that slopes downward as it approaches the scribe line 3) as shown in Fig. 9. In this case, it is preferable to move the cleaving bar 5 along an imaginary straight line shown in the figure, that is, an imaginary straight line that passes through the scribe line 3 and extends in the thickness direction of the curved scribe line formation region 2s.

[0053] In the above embodiment, the breaking bar 5 is pressed against the glass ribbon 2 (scribe line formation region 2s) at the same or approximately the same height as the scribe line 3, but may be pressed against a portion of the glass ribbon 2 above the scribe line 3. Here, the portion above the scribe line 3 refers to a portion of the glass ribbon 2 that is not curved in the vertical direction and is a predetermined distance above the scribe line 3. This predetermined distance is set to 5 mm or more and less than 70 mm. In addition, considering that the glass ribbon 2 has an effective region (a region that becomes a glass sheet of a product after breaking), this predetermined distance may be set to 5 mm or more and less than the distance from the scribe line 3 to the lower end of the effective region. In this case, the predetermined distance is set to 5 mm or more and less than 20 mm, taking into consideration the effective region of the glass ribbon 2 in this embodiment.

[0054] Furthermore, in the above embodiment, the pressing side end 5a of the breaking bar 5 is formed so as to extend linearly along the width direction. However, when the glass ribbon 2 is broken along the scribe line 3, the shape along the width direction of the glass ribbon 2 may be curved to be convex on one side (the surface 2a side) due to the fact that the warp along the width direction does not completely disappear. In this case, the breaking is performed using the breaking bar 5 having the pressing side end 5a whose shape along the width direction (shape in cross section) is curved to be convex on the same side as the glass ribbon 2. That is, the pressing side end 5a whose shape along the width direction is curved to be convex on the same side as the glass ribbon 2 is pressed against the scribe line formation region 2s of the glass ribbon 2 whose shape along the width direction is curved, whereby the glass ribbon 2 is broken along the scribe line 3. Therefore, in this case, it is possible to prevent the occurrence of cracks or breaking errors when bending and breaking a glass ribbon that is curved in the width direction using a breaking bar 5 whose pressing side end 5a is shaped to be in a straight line in the width direction.

[0055] In addition, in the above embodiment, the support means 4 supports the portion 2x of the glass ribbon 2 to be cut out by a pair of claws 11ax of the chuck 11a, but instead of this, the portion 2x to be cut out may be supported by an adsorption pad that adsorbs the front or back surface of the portion 2x to be cut out.

[0056] Furthermore, in the above embodiment, the support means 4 is configured to perform a rotational movement along a circular orbit centered on the position of the cleaving bar 5 (the position shown by the solid line in FIG. 1), but it may also perform a rotational movement along a curved orbit other than a circular orbit. Furthermore, the operation of the support means 4 may be an operation other than a rotational operation as long as it is an operation capable of curving the scribe line formation region 2s. Also, the operating speed of the support means 4 may be switched from a high speed to a low speed not only once as described above, but two or more times, or the speed may be continuously reduced.

[0057] In the above embodiments, the scribe line formation region 2s of the glass ribbon 2 is curved so that the front surface 2a side is convex by the rotational operation of the support means 4 as shown in Fig. 5 or 8, but not only the scribe line formation region 2s but also the entire area located between the lowermost roller 12 and the uppermost chuck 11a may be curved. In the case where a regulating roller is used, the entire area located between the regulating roller and the uppermost chuck 11a may be curved. [Explanation of symbols]

[0058] 1. Glass plate manufacturing equipment 2. Glass ribbon 2a Surface of the glass ribbon 2b Back side of glass ribbon 2s scribe line forming area 2x Cutting section 2y Glass plate 3 Scribe line 4 Support means 5 Break bar 5a Pressing end of the breaking bar 6. Control Measures S Scribe means

Claims

1. A method for manufacturing a glass plate, comprising: a scribing step of forming a scribe line along a width direction of a glass ribbon moving downward in a vertical position; and a bending and splitting step of bending and splitting the glass ribbon along the scribe line in a state in which a portion to be cut out that is below the scribe line of the glass ribbon is supported by a supporting means, and cutting out the portion to be cut out as a glass plate, A method for manufacturing a glass plate, characterized in that in the bending and splitting process, the support means is rotated so that the scribe line formation area of ​​the glass ribbon is curved in the vertical direction, and the intended cutting portion is inclined at a predetermined inclination angle with respect to a vertical line, thereby reducing warping that occurs in the scribe line formation area, and the glass ribbon is bent and split by pressing a bending and splitting bar against the scribe line formation area.

2. 2. The method for manufacturing a glass plate according to claim 1, further comprising the step of pressing the breaking bar against a region where the scribe line is to be formed after the rotation of the supporting means is completed.

3. 2. The method for manufacturing a glass plate according to claim 1, wherein the breaking bar is pressed against a region where the scribe line is to be formed during the rotation of the supporting means.

4. 2. The method for manufacturing a glass plate according to claim 1, wherein the supporting means is temporarily stopped during the rotation, the breaking bar is pressed against the region where the scribe line is to be formed, and then the supporting means is rotated again.

5. The method for manufacturing a glass plate according to any one of claims 1 to 3, characterized in that the supporting means is rotated at a relatively high speed and then at a relatively low speed, and thereafter the bending bar is pressed against the formation area of ​​the scribe line.

6. 6. The method for manufacturing a glass sheet according to claim 1, wherein the breaking bar is pressed against a portion above the scribe line in a region in which the glass ribbon is formed.

7. The method for manufacturing a glass plate according to any one of claims 1 to 6, characterized in that a pressing side end of the breaking bar, which has a curved shape along the width direction that is convex on one side, is pressed against a scribe line formation region, which has a curved shape along the width direction that is convex on the same side as the scribe line formation region.

8. A glass sheet manufacturing apparatus comprising: a scribing means for forming a scribe line along a width direction of a glass ribbon moving downward in a vertical position; a supporting means for supporting a portion to be cut out that is below the scribe line of the glass ribbon; a breaking bar that is pressed against an area of ​​the glass ribbon where the scribe line is formed; and a control means for controlling each operation of the supporting means and the breaking bar in order to break the glass ribbon along the scribe line and cut out the portion to be cut out as a glass sheet, The control means controls the operations of the support means and the breaking bar so that, when bending and breaking the glass ribbon, the support means is rotated so that the scribe line formation area of ​​the glass ribbon is curved in the vertical direction, and the intended cutting portion is inclined at a predetermined inclination angle with respect to a vertical line, thereby making it possible to press the breaking bar against the scribe line formation area in a state in which warping occurring in the scribe line formation area is reduced.

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