JP7492680B2 - Glass plate breaking device and method for manufacturing glass plate - Google Patents

Description

This disclosure relates to a glass sheet breaking device and a glass sheet manufacturing method.

As is well known, the manufacturing process of glass sheets often includes a step of separating the portions of the glass sheet that are no longer needed for the product (hereinafter referred to as non-product portions) from the original glass sheet that will become the product glass sheet, and discarding the separated non-product portions. One example of a form for carrying out this process is disclosed in Patent Document 1.

In the embodiment disclosed in the document, first, a glass plate on which a scribe line is formed along the boundary between the portion that will later become the product glass plate (hereinafter referred to as the product portion) and the non-product portion is folded and broken along the scribe line. After that, the non-product portion that is separated from the product portion as a result of folding and breaking is collected and discarded.

In carrying out the above embodiment, a bending and splitting device 100 as shown in Figs. 12 and 13 is used. Fig. 12 shows the state of the glass sheet G before bending and splitting, and Fig. 13 shows the state after bending and splitting. The bending and splitting device 100 includes a holding member 200 that holds the glass sheet G on which a scribe line S is formed on the upper surface Gs side along the boundary between the product portion Ga and the non-product portion Gb, a bending and splitting member 300 that applies bending stress to the portion where the scribe line S is formed by pressing the glass sheet G held by the holding member 200 from the lower surface Gt side, thereby bending and splitting the glass sheet G along the scribe line S, and a recovery member 400 that recovers the product portion Ga and the non-product portion Gb that is separated by bending and splitting by the bending and splitting member 300.

The holding member 200 includes a first mounting table 500 and a second mounting table 600 that support the product portion Ga and the non-product portion Gb of the glass plate G from the bottom surface Gt, respectively, and a first pressing member 700 and a second pressing member 800 that press the product portion Ga and the non-product portion Gb from the top surface Gs, respectively. The splitting member 300 can move along the thickness direction (Z direction) of the glass plate G, and can press the glass plate G between the two mounting tables 500, 600. The recovery member 400 includes a suction pad 900 that adsorbs the top surface Gs of the non-product portion Gb in order to recover the non-product portion Gb after splitting.

The first pressing member 700 and the second pressing member 800 are each formed long along the direction in which the scribe line S extends (Y direction). The recovery member 400 is provided with a plurality of suction pads 900, which are arranged along the direction in which the scribe line S extends.

The second pressing member 800 and each suction pad 900 contact the non-product portion Gb of the glass plate G from the upper surface Gs side, but the positions of the areas in contact with the non-product portion Gb are different between the two 800 and 900. In more detail, when observed from the direction in which the scribe line S extends (when observed from the Y direction), the contact area A1 (shown by a thick line in FIG. 12) where the second pressing member 800 contacts the non-product portion Gb and the contact area A2 (shown by a thick line in FIG. 13) where the suction pad 900 contacts the non-product portion Gb are positioned so as to be side-by-side in the width direction (X direction) of the non-product portion Gb. Note that the contact area A2 is located closer to the scribe line S (closer to the boundary between the product portion Ga and the non-product portion Gb) than the contact area A1.

JP 2018-154514 A

However, when the above-mentioned bending and breaking device 100 is used, there is a problem that the bending and breaking of the glass sheet G is likely to occur when the width (dimension along the X direction) of the non-product portion Gb of the glass sheet G is narrow. This is because the above-mentioned contact area A1 and contact area A2 are positioned side by side in the width direction of the non-product portion Gb, and when the width of the non-product portion Gb is narrow, it is difficult to secure both contact area A1 and contact area A2 on the non-product portion Gb.

In light of the above, the technical problem to be solved is to prevent defective bending when dividing a non-product part from a glass sheet by bending, even if the width of the non-product part is narrow.

The glass plate breaking device for solving the above problem includes a holding member for holding a glass plate on one side of which a scribe line is formed along the boundary between a product portion and a non-product portion, a bending member for pressing the glass plate held by the holding member from the other side to apply bending stress to the portion on which the scribe line is formed, thereby breaking the glass plate along the scribe line, and a recovery member for recovering the non-product portion separated from the product portion as a result of the breaking by the bending member, the holding member having a pressing portion for pressing the non-product portion to hold the glass plate, the recovery member having an adsorption portion for adsorbing the non-product portion to recover the non-product portion, and both the pressing portion and the adsorption portion being configured to contact the non-product portion from the same side of the glass plate, and being configured such that, when observed from the direction in which the scribe line extends, the width of a first contact area where the pressing portion and the non-product portion come into contact overlaps with the width of a second contact area where the adsorption portion and the non-product portion come into contact.

When observed from the direction in which the scribe line extends, this device is configured so that the width of the first contact area where the pressing portion and the non-product portion come into contact overlaps with the width of the second contact area where the suction portion and the non-product portion come into contact. By overlapping the widths of both contact areas in this way, it becomes possible to easily secure both the first contact area and the second contact area on the non-product portion even if the width of the non-product portion is narrow. As a result, it is possible to prevent the occurrence of folding defects. Furthermore, because it is possible to prevent the occurrence of folding defects, it is also possible to avoid a decrease in the production efficiency of the glass sheet.

In the above configuration, it is preferable that the holding member has multiple pressing portions and the recovery member has multiple suction portions.

In this way, by having the holding member have multiple pressing parts, it is possible to reduce the cost of the pressing parts compared to, for example, a case in which the holding member has a single long pressing part (long along the direction in which the scribe line extends). In addition, by having multiple pressing parts and suction parts, for example, even if a malfunction occurs in a particular pressing part or suction part, it is sufficient to replace only that pressing part or suction part. Therefore, equipment costs and maintenance costs can also be reduced.

In the above configuration, when observed from the direction in which the scribe line extends, it is preferable that the entire width of the relatively narrow region of the first contact region and the second contact region is contained within the width of the relatively wide region.

In this way, the total width of the relatively narrow area is contained within the width of the relatively wide area, making it possible to prevent defective folding even when the width of the non-product part is narrower.

In the above configuration, it is preferable that the first contact regions and the second contact regions are arranged alternately along the direction in which the scribe line extends.

This allows the pressing of the non-product parts by the pressing part and the suction of the non-product parts by the suction part to be stabilized.

A method for manufacturing a glass plate to solve the above problem includes a holding step of holding a glass plate having a scribe line formed on one side along the boundary between a product portion and a non-product portion, a bending step of pressing the glass plate from the other side during the holding step to apply bending stress to the portion where the scribe line is formed, thereby bending the glass plate along the scribe line, and a recovery step of recovering the non-product portion separated from the product portion as a result of the bending step after the bending step is performed, the non-product portion being pressed to hold the glass plate in the holding step, and the non-product portion being sucked to recover the non-product portion in the recovery step, the holding of the non-product portion in the holding step and the sucking of the non-product portion in the recovery step being performed on the same surface of the non-product portion, and the method is characterized in that, when observed from the direction in which the scribe line extends, the width of the region of the non-product portion held in the holding step and the width of the region of the non-product portion sucked in the recovery step overlap.

This method makes it possible to obtain the same effects and advantages as those already described for the glass plate breaking device.

According to the glass sheet breaking device and glass sheet manufacturing method disclosed herein, when dividing a non-product portion from a glass sheet by breaking it, it is possible to prevent the occurrence of poor breaking even if the width of the non-product portion is narrow.

FIG. 2 is a side view showing the glass plate breaking device. FIG. 2 is a front view showing the glass plate breaking device. FIG. 2 is a front view showing the glass plate breaking device. FIG. 2 is a plan view showing the first contact region to the third contact region. FIG. 2 is a side view illustrating a method for manufacturing a glass plate. FIG. 2 is a side view illustrating a method for manufacturing a glass plate. FIG. 2 is a side view illustrating a method for manufacturing a glass plate. FIG. 2 is a side view illustrating a method for manufacturing a glass plate. FIG. 2 is a side view illustrating a method for manufacturing a glass plate. 13 is a bottom view showing a second pressing portion and a suction pad as viewed from below in a modified example of the glass plate breaking device. FIG. 13 is a plan view showing the first contact region to the third contact region in a modified example. FIG. FIG. 1 is a side view showing a conventional glass plate breaking device. FIG. 1 is a side view showing a conventional glass plate breaking device.

The following describes a glass plate breaking device and a glass plate manufacturing method according to an embodiment, with reference to the attached drawings. Note that the X direction, Y direction, and Z direction shown in each drawing referred to in the description of the embodiment are mutually orthogonal.

<Glass plate breaking device>
The glass plate breaking device 1 shown in Fig. 1 (hereinafter simply referred to as the breaking device 1) is a device that breaks a glass plate G having a scribe line S formed along the boundary between a product portion Ga and a non-product portion Gb, thereby dividing the two portions Ga and Gb, and collects the divided non-product portion Gb for disposal (see Figs. 6 and 9). Note that the product portion Ga is a portion that will later become a product glass plate, and the non-product portion Gb is a portion that will be discarded.

The bending and breaking device 1 includes a holding member 2 that holds a glass sheet G with a scribe line S formed on the upper surface Gs, a bending and breaking member 3 that presses the glass sheet G held by the holding member 2 from the lower surface Gt to bend and break it along the scribe line S, and a recovery member 4 that recovers the product part Ga and the non-product part Gb that is separated as a result of bending and breaking by the bending and breaking member 3.

The glass sheet G to be broken is rectangular, and the scribe line S is formed in a straight line parallel to one side of the rectangle formed by the glass sheet G (in this embodiment, it is formed along the Y direction). The thickness of the glass sheet G is, for example, 2 mm or less, and preferably 0.2 mm to 0.7 mm. The width (dimension along the X direction) of the non-product portion Gb of the glass sheet G is, for example, 45 mm or less, preferably 35 mm or less, and more preferably 25 mm or less. On the other hand, if the width of the non-product portion Gb of the glass sheet G is too narrow, it becomes difficult to break it, so the lower limit is preferably 15 mm or more.

The holding member 2 includes a first support member 5 and a second support member 6 that support the product portion Ga and the non-product portion Gb of the glass sheet G from the bottom surface Gt, respectively, and a first pressing member 7 and a second pressing member 8 that press the product portion Ga and the non-product portion Gb from the top surface Gs, respectively. The holding member 2 is capable of holding the glass sheet G in a flat position by sandwiching the product portion Ga in the thickness direction between the first support member 5 and the first pressing member 7, and sandwiching the non-product portion Gb in the thickness direction between the second support member 6 and the second pressing member 8 (see FIG. 5).

Here, the first support member 5 and the second support member 6 are not limited to the support table-like members shown in FIG. 1, and may be, for example, conveyors (belt conveyors, roller conveyors, etc.). As a specific example, the conveying direction may be the X direction, the second support member 6 may be a relatively upstream conveyor, and the first support member 5 may be a relatively downstream conveyor. In this case, the glass sheet G is conveyed into the bending and cutting device 1 by both conveyors so that the scribe line S is located above the bending and cutting member 3, and the product part Ga after cutting is conveyed out of the bending and cutting device 1 by the downstream conveyor. Alternatively, the conveying direction may be the X direction, the second support member 6 may be a relatively downstream conveyor, and the first support member 5 may be a relatively upstream conveyor. Alternatively, the conveying direction may be the Y direction.

The first pressing member 7 and the second pressing member 8 can each move in the vertical direction (Z direction) as shown by the arrows in FIG. 1. The pressing members 7 and 8 are configured to press the product portion Ga and the non-product portion Gb, respectively, as they move downward.

The first pressing member 7 has a first pressing portion 7a which is a portion that contacts the upper surface Gs of the product portion Ga and directly presses the product portion Ga. Similarly, the second pressing member 8 has a second pressing portion 8a which is a portion that contacts the upper surface Gs of the non-product portion Gb and directly presses the non-product portion Gb. Each of the first pressing portion 7a and the second pressing portion 8a is formed in a cylindrical shape with a center line extending in the Y direction. Of course, this is not limited to this, and as a modified example of this embodiment, for example, both pressing portions 7a, 8a may be formed in a square prism shape. The first pressing portion 7a and the second pressing portion 8a are made of an elastic material and can be elastically deformed by an external force. For example, rubber (natural rubber, synthetic rubber, etc.) or sponge can be used as the material of the first pressing portion 7a and the second pressing portion 8a. Also, as a modified example of this embodiment, the first pressing portion 7a and the second pressing portion 8a may be made of a brush.

The recovery member 4 has a suction pad 4a as an adsorption part that contacts the upper surface Gs of the non-product part Gb after cutting and adsorbs the non-product part Gb. The adsorption surface of the suction pad 4a is circular. Of course, this is not limited to this, and as a modification of this embodiment, the adsorption surface may be rectangular, polygonal, elliptical, etc. The suction pad 4a can move along a direction inclined with respect to the vertical direction (hereinafter referred to as the inclined direction) as shown by the arrow in FIG. 1. The suction pad 4a is configured to move downward along the inclined direction and then adsorb the non-product part Gb after cutting. The angle between the inclined direction and the vertical direction is preferably 1° to 30°, more preferably 1.5° to 15°, and most preferably 2° to 10°. For example, urethane can be used as the material for the part of the suction pad 4a that contacts the non-product part Gb.

The reason why the suction pad 4a is moved along the inclined direction as described above is as follows. After cutting, the non-product part Gb has its end (the end adjacent to the cut product part Ga) lifted by the breaking member 3 (see FIG. 7). The non-product part Gb in this state is then sucked up by the suction pad 4a. For this reason, if the suction pad 4a is brought into contact with the non-product part Gb while keeping the top surface Gs of the non-product part Gb, which has been tilted relative to the horizontal plane as a result of the lifting, as parallel as possible to the suction surface of the suction pad 4a, this is advantageous for smooth suction.

As a modification of this embodiment, the suction pad 4a does not necessarily have to be able to move along the inclined direction. For example, the suction pad 4a may be able to move along the up-down direction.

The second pressing member 8 and the suction pad 4a are both mounted on a common moving mechanism 9. The moving mechanism 9 is capable of moving freely along the XZ plane. The moving mechanism 9 has the function of transporting the non-product parts Gb after separation to a disposal conveyor (not shown) via the suction pad 4a that has adsorbed the non-product parts Gb.

The breaking and splitting member 3 is formed long along the Y direction and is disposed between the first support member 5 and the second support member 6. The breaking and splitting member 3 is capable of moving along the vertical direction as shown by the arrow in FIG. 1. As the breaking and splitting member 3 moves upward, it applies a bending stress to the portion of the glass sheet G where the scribe line S is formed, thereby breaking the glass sheet G.

The bending member 3 has a pressing surface that contacts the lower surface Gt of the glass sheet G and directly presses the glass sheet G, and a pair of inclined surfaces inclined on both sides of the pressing surface. The pressing surface contacts the lower surface Gt of the glass sheet G while straddling the product portion Ga and the non-product portion Gb with the scribe line S in between. The width of the pressing surface (the dimension along the X direction) is preferably 3 mm to 15 mm. In addition, the angle between the pressing surface and the inclined surface is preferably 30° to 50°.

As shown in Figures 2 and 3, there are multiple second pressing portions 8a and multiple suction pads 4a, and the multiple second pressing portions 8a and multiple suction pads 4a are arranged alternately along the Y direction. Both the second pressing portions 8a and the suction pads 4a can move (up and down) independently of each other. The lengths along the Y direction are uneven between the multiple second pressing portions 8a, but may be uniform. As a result, the spacing between adjacent suction pads 4a, 4a is also uneven, but may be uniform.

The reason why the lengths in the Y direction between the multiple second pressing portions 8a are unequal as described above is for the following purpose. The glass sheet G to be broken has product parts Ga corresponding to various standard sizes (e.g., G8 size, G8.5 size, etc.). And, regardless of which standard size the glass sheet G to be broken has product parts Ga corresponding to, the purpose is that the second pressing portions 8a, not the suction pads 4a, come into contact with the end of the glass sheet G in the Y direction.

As described above, the second pressing portion 8a is provided in multiple units, while the first pressing portion 7a is a single member formed in an elongated shape along the Y direction. Of course, this is not the only option, and as a modified example of this embodiment, the first pressing portion 7a may be made up of multiple members.

Figure 4 shows the glass plate G in a plan view from above. The areas indicated by diagonal lines in the figure are a first contact area A1 where the second pressing portion 8a and the non-product portion Gb come into contact when the second pressing portion 8a presses the non-product portion Gb, a second contact area A2 where the suction pad 4a and the suction pad 4a come into contact when the non-product portion Gb is adsorbed, and a third contact area A3 where the first pressing portion 7a and the suction pad 7a come into contact when the product portion Ga is pressed. The first contact area A1 to the third contact area A3 are all areas that exist on the upper surface Gs of the glass plate G.

Due to the arrangement of the multiple second pressing portions 8a and the multiple suction pads 4a described above, the first contact area A1 and the second contact area A2 are arranged alternately along the direction in which the scribe line S extends (Y direction). On the other hand, due to the configuration of the first pressing portion 7a described above, the third contact area A3 is a single elongated area along the direction in which the scribe line S extends.

The first contact area A1 is a substantially rectangular area. This is because when the second pressing portion 8a presses the non-product portion Gb, the lower part of the cylinder formed by the second pressing portion 8a is deformed flat (elastically deformed) as it comes into contact with the upper surface Gs of the non-product portion Gb. For the same reason, the third contact area A3 is also a substantially rectangular area. On the other hand, the second contact area A2 is a substantially circular area. This is because the suction surface of the suction pad 4a is circular.

When observed from the direction in which the scribe line S extends, the width W2 of the second contact area A2 is wider than the width W1 of the first contact area A1. The entire width (width W1) of the first contact area A1 is contained within the width W2 of the second contact area A2. The size and arrangement of the second pressing portion 8a and the suction pad 4a are adjusted so that this condition is met.

As a modification of this embodiment, the second pressing portions 8a and the suction pads 4a do not have to be arranged alternately in the arrangement of the multiple second pressing portions 8a and the multiple suction pads 4a. In other words, the second pressing portions 8a may be continuous in part of the arrangement, or the suction pads 4a may be continuous. Furthermore, the size relationship between the width W1 of the first contact area A1 and the width W2 of the second contact area A2 may be reversed from this embodiment, or the width W1 and the width W2 may be equal. In addition, it is not essential that the entire width of one of the contact areas A1, A2 is contained within the width of the other area, and it is sufficient that at least a portion of the contact areas A1, A2 overlap in the X direction.

<Method of manufacturing glass plate>
Hereinafter, there will be described a method for manufacturing a glass plate using the above-mentioned breaking apparatus 1. This manufacturing method includes a holding step P1 (FIG. 5), a breaking step P2 (FIG. 6), and a recovery step P3 (FIGS. 7 to 9).

As shown in FIG. 5, in the holding step P1, the glass sheet G on which the scribe line S is formed is held by the holding member 2. Specifically, as the first holding member 7 and the second holding member 8 are moved downward, the product portion Ga and the non-product portion Gb of the glass sheet G, whose lower surface Gt is supported by the first supporting member 5 and the second supporting member 6, are pressed from the upper surface Gs side, respectively. This holds the glass sheet G in a flat position. The scribe line S is formed on the glass sheet G by a wheel cutter, laser irradiation, or the like, before the holding step is performed.

As shown in FIG. 6, in the bending process P2, the glass sheet G is pressed from the lower surface Gt side and bent and broken along the scribe line S. Specifically, while the glass sheet G is held by the holding member 2, the bending member 3 is moved upward to lift the portion of the glass sheet G where the scribe line S is formed. This causes the portion where the scribe line S is formed to deform so that the upper surface Gs side becomes convex, and bending stress acts on the portion as it is deformed. Due to the action of this bending stress, the median crack contained in the scribe line S progresses in the thickness direction of the glass sheet G, and the glass sheet G is divided into a product portion Ga and a non-product portion Gb.

As shown in FIG. 7, in the recovery process P3, first, the non-product part Gb after the division is adsorbed by the suction pad 4a in preparation for collecting the non-product part Gb after the division for disposal. Specifically, the suction pad 4a is moved downward, and the suction surface of the suction pad 4a is brought into contact with the upper surface Gs of the non-product part Gb, and then the non-product part Gb is adsorbed to the suction pad 4a using negative pressure. Note that it is preferable that the adsorption of the non-product part Gb by the suction pad 4a is performed while the end of the non-product part Gb (the end adjacent to the product part Ga) is lifted by the splitting member 3 and the second pressing member 8 is holding the non-product part Gb. This is for the purpose of preventing the quality of the product part Ga from deteriorating due to contact between the product part Ga and the non-product part Gb after division. At this time, the upper surface Gs of the non-product part Gb adsorbed to the suction pad 4a is inclined.

When the suction of the non-product part Gb by the suction pad 4a is completed, the second pressing member 8 is then moved upward as shown in FIG. 8, and the pressing of the non-product part Gb by the second pressing member 8 is released. Note that even when releasing the pressing, it is preferable to maintain the lifting of the end of the non-product part Gb by the cleavage member 3.

When the pressing of the non-product parts Gb by the second pressing member 8 described above is completed, the moving mechanism 9 is then moved upward as shown in FIG. 9 to collect the cut non-product parts Gb. The collected non-product parts Gb are carried to a disposal conveyor by the moving mechanism 9, and then transported to a disposal location by the conveyor for disposal. Meanwhile, the cut product parts Ga are cleaned, inspected, etc., and then turned into product glass plates. This completes the manufacturing method.

The main functions and effects of the above-mentioned cutting device 1 and manufacturing method are described below.

In the above-mentioned bending device 1 and manufacturing method, when observed from the direction in which the scribe line S extends (Y direction), the width W1 of the first contact area A1 where the second pressing portion 8a and the non-product portion Gb contact each other and the width W2 of the second contact area A2 where the suction pad 4a and the non-product portion Gb contact each other overlap. By overlapping the widths W1 and W2 of both contact areas A1 and A2 in this way, it is possible to easily secure both the first contact area A1 and the second contact area A2 on the non-product portion Gb even if the width (dimension along the X direction) of the non-product portion Gb is narrow. As a result, it is possible to prevent the occurrence of bending defects in the glass sheet G.

Here, the bending device 1 and the manufacturing method described in the above embodiment can be modified as shown in Figs. 10 and 11. Fig. 10 is a bottom view showing the second pressing portion 8a and the suction pad 4a viewed from below. As shown in the figure, instead of the multiple second pressing portions 8a and the multiple suction pads 4a in the above embodiment, a single second pressing portion 8a and multiple suction pads 4a formed long along the Y direction may be used. In this modified example, the second pressing portion 8a has the same number of through holes 8aa (through holes that penetrate the second pressing portion 8a vertically) as the number of suction pads 4a. When observed from the Z direction, the opening area of the through hole 8aa is one size larger than that of the suction pad 4a. The suction pad 4a can move up and down within this through hole 8aa. In this modified example, as shown in FIG. 11, the size relationship between the width W1 of the first contact area A1 and the width W2 of the second contact area A2 is the opposite of that in the above embodiment (width W1 > width W2), and the entire width (width W2) of the second contact area A2 is contained within the width W1 of the first contact area A1.

REFERENCE SIGNS LIST 1 Breaking device 2 Holding member 3 Breaking member 4 Recovery member 4a Suction pad 8a Second pressing portion A1 First contact area A2 Second contact area G Glass plate Ga Product portion Gb Non-product portion Gs Upper surface Gt Lower surface P1 Holding step P2 Breaking step P3 Recovery step S Scribe line W1 Width of first contact area W2 Width of second contact area

Claims (5)

a holding member for holding a glass plate having a scribe line formed on one side along the boundary between a product portion and a non-product portion;
a bending/breaking member that applies bending stress to the portion where the scribe line is formed by pressing the glass plate held by the holding member from the other surface side, thereby bending/breaking the glass plate along the scribe line;
a recovery member that recovers the non-product portion separated from the product portion by the folding and splitting member,
The holding member has a pressing portion that presses the non-product portion to hold the glass plate,
The recovery member has an adsorption portion that adsorbs the non-product portion in order to recover the non-product portion,
A glass plate breaking device configured so that both the pressing portion and the suction portion contact the non-product portion from the same side of the glass plate,
A glass plate breaking device characterized in that, when observed from the direction in which the scribe line extends, the width of a first contact area where the pressing portion and the non-product portion come into contact and the width of a second contact area where the suction portion and the non-product portion come into contact are configured to overlap. The holding member has a plurality of the pressing portions,
The glass plate breaking apparatus according to claim 1 , wherein the recovery member has a plurality of the suction portions. The glass sheet breaking device according to claim 1 or 2, characterized in that, when observed from the direction in which the scribe line extends, the entire width of the relatively narrow region of the first contact region and the second contact region is contained within the width of the relatively wide region. The glass sheet breaking device according to any one of claims 1 to 3, characterized in that the first contact areas and the second contact areas are arranged alternately along the direction in which the scribe lines extend. a holding step of holding a glass plate having a scribe line formed on one side along a boundary between a product portion and a non-product portion;
a bending/breaking step of pressing the glass plate from the other surface side during the holding step to apply bending stress to the portion where the scribe line is formed, thereby bending the glass plate along the scribe line;
and a recovery step of recovering the non-product part separated from the product part by the folding and breaking step,
In the holding step, the non-product portion is pressed to hold the glass plate,
In the recovery step, the non-product parts are adsorbed to recover the non-product parts,
A method for manufacturing a glass plate, comprising the steps of: holding the non-product portion in the holding step; and suctioning the non-product portion in the collecting step, the non-product portion being held against the same surface of the non-product portion;
a width of a region of the non-product portion that is pressed in the holding process and a width of a region of the non-product portion that is adsorbed in the recovery process are made to overlap when observed from the direction in which the scribe line extends.

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