Method for manufacturing a glass sheet and manufacturing device thereof

Abstract

The method for manufacturing a glass sheet includes: a first cutting step of cutting a glass ribbon (G) being transported while being formed by a first cutting device (2) to cut out a glass sheet; a second cutting step of cutting the glass ribbon (G) by a second cutting device (3) at a time when the first cutting device (2) is not in operation; and a first detection step of detecting the presence or absence of the glass ribbon (G) by a first sensor (30). The method for manufacturing a glass sheet includes a switching step for switching the first cutting step to the second cutting step based on a detection result in the first detection step.

Description

Technical Field

[0001] The present invention relates to glass plate manufacturing technology, and more specifically to a technology for cutting a glass plate by cutting a glass strip that is being transported during forming, and a second cutting that cuts the glass strip without performing the first cutting. Background Technology

[0002] In the field of glass sheet manufacturing, it is known that a first cutting process is performed to cut a glass strip that moves continuously downward in a forming zone to a predetermined length along the width direction, thereby sequentially cutting out glass sheets. In this case, the melting furnace and other components of the glass sheet manufacturing equipment typically operate continuously. Therefore, even if the device used for the first cutting process is unavailable due to maintenance, the glass strip continues to be formed. Thus, even if the first cutting process is not performed, it is necessary to cut and recycle the glass strip that is still being formed.

[0003] To address this requirement, for example, Patent Document 1 discloses a second cutting process that cuts the glass ribbon using a device with a different structure than the device in the first cutting process without performing the first cutting process. The device used in this second cutting process includes a holding member for holding the glass ribbon, a pressing member for applying stress to the glass ribbon while it is held by the holding member, and a scribing member for engraving scribing lines on the stress-applying portion of the glass ribbon.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Chinese Utility Model Announcement No. 205473369 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In the aforementioned glass sheet manufacturing method, for example, if a cutting defect occurs during the first cutting process of the glass strip, a crack may propagate along the transport direction, causing the glass strip to break. Additionally, the glass strip may be damaged or broken due to the rollers used to transport it. Among these breakages, some result in the complete rupture and disappearance of the formed and transported glass strip. In the case of glass strip breakage, the first cutting process can be interrupted and a second cutting process can begin. If glass strip forming has resumed after the breakage, the second cutting process begins. This switch from the first cutting process to the second cutting process has historically been performed by operator intervention. Therefore, a smooth switch is difficult to achieve.

[0009] Based on the above viewpoints, the objective of this invention is to smoothly switch from the first cutting process to the second cutting process.

[0010] Solution for solving the problem

[0011] The first aspect of the present invention, made to solve the above-mentioned problems, is a method for manufacturing a glass plate, comprising: a first cutting step, wherein a glass plate is cut by cutting a glass strip being transported during forming using a first cutting device; and a second cutting step, wherein the glass strip is cut using a second cutting device when the first cutting device is not in operation. The method for manufacturing the glass plate is characterized in that the method includes a first detection step for detecting the presence or absence of a glass strip using a sensor, and a switching step for switching the first cutting step to the second cutting step based on the detection result in the first detection step.

[0012] According to this structure, the switching process for changing from the first cutting process to the second cutting process is based on the detection results of a sensor that detects the presence or absence of the glass ribbon, thus enabling a smooth switching. Furthermore, by using a sensor to detect the presence or absence of the glass ribbon, it is possible to accurately determine, for example, the restart of glass ribbon forming, allowing the second cutting process to begin at the appropriate time.

[0013] In this structure, the sensor may also be arranged at multiple locations corresponding to the width of the glass strip.

[0014] In this way, multiple sensors can be used to detect the presence or absence of the glass ribbon at multiple locations in the width direction, thus enabling a close understanding of the shape of the glass ribbon when it breaks, the forming state of the glass ribbon when the forming process restarts after the breakage, and so on.

[0015] In the above structure, the sensor may also be respectively provided corresponding to at least both ends and the middle part of the glass strip in the width direction, and can identify the first state in which either end of the glass strip in the width direction is transported while being formed, the second state in which either end of the glass strip in the width direction and the middle part in the width direction are transported while being formed, the third state in which both ends of the glass strip in the width direction are transported while being formed, and the fourth state in which the entire width direction of the glass strip is transported while being formed, based on the detection result in the first detection process.

[0016] In this way, the forming process and transportation process of the glass ribbon when the forming process restarts after the breakage can be distinguished into the four states listed above, so that the switching process and the second cutting process can be carried out appropriately in accordance with the four states.

[0017] In the above structure, it is also possible that, in the first detection step, the sensor detects the presence or absence of the glass strip at a position upstream of the first cutting device and the second cutting device in the transport direction.

[0018] In this way, based on the confirmation by sensors that glass pieces have fallen due to breakage, appropriate countermeasures can be taken for the first and second cutting devices. Furthermore, based on the confirmation of the glass ribbon's forming state when forming resumes after breakage, appropriate switching and second cutting processes can be performed.

[0019] In this structure, it is also possible that, during the switching process, based on the detection result in the first detection process, the components of the second cutting device are moved from the retreat area to the cutting area.

[0020] Here, the term "cutting area" refers to the area where the second cutting device cuts the glass ribbon. The term "retreat area" refers to the area where the second cutting device retreats from the cutting area (e.g., an area separated from the glass ribbon's transport path by 500mm to 2000mm). Furthermore, the term "constituent elements of the second cutting device" can refer to all or only a portion of the constituent elements of the second cutting device.

[0021] In this way, after confirming that the glass sheet or other parts have not fallen into the cutting area after the glass ribbon breaks, the components of the second cutting device can be moved from the retraction area into the cutting area. This avoids undesirable situations such as collisions between the glass sheet or other parts and the components of the second cutting device when the glass ribbon cutting process begins using the second cutting device. Therefore, the retraction area is preferably the area where the glass sheet or other parts will not fall. Furthermore, according to this structure, the components of the second cutting device can be appropriately moved in after confirming the forming state of the glass ribbon when forming resumes following breakage.

[0022] In this structure, the component of the second cutting device may be a part of all the components of the second cutting device and is the first component to enter when the cutting process by the second cutting device begins.

[0023] In this way, the earliest entering component is protected from the effects of falling glass sheets, and other components that enter later are also reliably protected. Furthermore, according to this structure, the earliest entering component can be properly operated based on confirmation of the glass strip's forming state when forming resumes after breakage.

[0024] In this structure, the sensor may be respectively positioned corresponding to at least both ends of the glass strip in the width direction. The earliest entering component is any one or both of the holding members used to hold both ends of the glass strip in the width direction during the cutting process in the second cutting step, such that the holding member corresponding to the end of the glass strip in the width direction detected by the sensor enters, and the holding member corresponding to the end of the glass strip in the width direction detected by the sensor does not enter.

[0025] In this way, sensors are respectively installed corresponding to at least both ends of the glass strip in the width direction. Therefore, one sensor detects the presence or absence of one end of the glass strip in the width direction, and the other sensor detects the presence or absence of the other end. Furthermore, at the location corresponding to the detected end of the glass strip in the width direction, no glass fragments or the like fall due to breakage. Therefore, even if the retaining member corresponding to that end enters, no adverse situations such as glass fragments colliding with the retaining member will occur. On the other hand, at the location corresponding to the absent end of the glass strip in the width direction, glass fragments or the like fall due to breakage. Therefore, the retaining member corresponding to that end does not enter, thereby preventing adverse situations such as glass fragments colliding with the retaining member. Additionally, according to this structure, the detected end of the glass strip in the width direction continues to be transported during forming, so it is necessary to pre-cut this end in the width direction. Therefore, by inserting the retaining member corresponding to this end in the width direction, the end in the width direction can be cut to an appropriate length. On the other hand, the glass strip that is not detected in the width direction is placed until it is detected in the subsequent forming process, so that the retaining member corresponding to the width direction end does not enter.

[0026] In the aforementioned structure, the method for manufacturing the glass plate may also include a second detection step in which the presence or absence of the glass strip is detected at a position downstream of the sensor used in the first detection step in the transport direction using sensors that are respectively provided corresponding to both ends of the glass strip in at least the width direction. Based on the detection results of these sensors, the glass strip is cut using the components of the second cutting device that entered in the switching step.

[0027] In this way, the cutting process of the glass strip using the components of the second cutting device (including the aforementioned holding member) is carried out accurately by incorporating the detection results from the second detection process in addition to the detection results from the first detection process already described.

[0028] In this structure, the components of the second cutting device may include a cutting blade used in cutting the glass strip, and the cutting blade is pressed against the glass strip based on the detection results in the second detection process.

[0029] In this way, the glass ribbon can be cut more accurately using the cutting blade and the aforementioned retaining components.

[0030] In this structure, the second cutting device may also include a pressing member that applies stress to the glass strip, and the stress applied to the glass strip by the pressing member is based on the detection results in the second detection process.

[0031] In this way, the glass ribbon can be cut more accurately using the cutting blade, pressing member, and the aforementioned holding member.

[0032] A second aspect of the present invention, made to solve the aforementioned problems, is a glass plate manufacturing apparatus comprising: a first cutting device that cuts a glass strip being transported during forming to produce a glass plate; and a second cutting device that cuts the glass strip when the first cutting device is not in operation. The glass plate manufacturing apparatus is characterized in that it includes a sensor for detecting the presence or absence of the glass strip and is configured to perform a switching process for switching the operation of the first cutting device to the operation of the second cutting device based on the detection result of the sensor.

[0033] Accordingly, the same effects as the described manufacturing method, which is substantially the same as the manufacturing apparatus, can be obtained.

[0034] Invention Effects

[0035] According to the present invention, the switching from the first cutting process to the second cutting process can be performed smoothly. Attached Figure Description

[0036] Figure 1 This is a side view showing the overall structure of a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0037] Figure 2 This is a schematic front view showing the main parts of a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0038] Figure 3 This is a schematic side view illustrating the operation of the first cutting device in a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0039] Figure 4 This is an enlarged schematic top view of the second cutting device in a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0040] Figure 5 This is an enlarged schematic top view of the second cutting device in a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0041] Figure 6 This is an enlarged side view of the second cutting device in a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0042] Figure 7 This is an enlarged schematic side view illustrating the function of the second cutting device in a glass plate manufacturing apparatus according to an embodiment of the present invention.

[0043] Figure 8 This is a main outline front view showing the state of the glass strip being cut by the second cutting device in a glass sheet manufacturing apparatus using an embodiment of the present invention.

[0044] Figure 9 This is a main outline front view showing the state of the glass strip being cut by the second cutting device in a glass sheet manufacturing apparatus using an embodiment of the present invention.

[0045] Figure 10a This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0046] Figure 10b This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0047] Figure 10c This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0048] Figure 11a This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0049] Figure 11b This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0050] Figure 11c This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0051] Figure 12a This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0052] Figure 12bThis is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0053] Figure 13a This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention.

[0054] Figure 13b This is a schematic front view showing the cutting of a glass strip using a glass sheet manufacturing apparatus according to an embodiment of the present invention. Detailed Implementation

[0055] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0056] Figure 1 This is a side view showing the overall structure of the glass sheet manufacturing apparatus according to this embodiment. As shown in the figure, the glass sheet manufacturing apparatus includes, as its main components, a glass strip G processing device 1, a first cutting device 2, and a second cutting device 3. It should be noted that, in the following description, the second main surface Gb side of the glass strip G ( Figure 1 The arrow X1 side) is taken as the "front side", and the first main surface Ga side ( Figure 1 The arrow Y1 side is referred to as the "rear side". In addition, in this embodiment, the downstream side of the glass belt G in the transport direction is referred to as "below (preferably vertically below)" and the upstream side is referred to as "above (preferably vertically above)".

[0057] The processing apparatus 1 includes: a forming zone 11, which continuously forms a glass strip G; a heat treatment zone 12, which heat-treats (anneales) the glass strip G; a cooling zone 13, which cools the glass strip G to near room temperature; and a conveying device 14, which is composed of roller pairs R arranged in multiple stages, one above the other, in the forming zone 11, the heat treatment zone 12 and the cooling zone 13.

[0058] The forming zone 11 and the heat treatment zone 12 are both furnaces surrounded by walls around the transport path of the glass strip G, and heating devices such as heaters for adjusting the temperature of the glass strip G are arranged in appropriate parts inside the furnace. On the other hand, the cooling zone 13 is not surrounded by walls around the transport path of the glass strip G but is open to the external environment at room temperature, and no heating devices such as heaters are provided.

[0059] A forming body 15 is disposed within the internal space of the forming zone 11, which forms a glass strip G from molten glass Gm using an overflow-pull method. Molten glass Gm supplied to the forming body 15 overflows from a groove (not shown) formed in the top 15a of the forming body 15. The overflowing molten glass Gm flows along the two wedge-shaped side surfaces 15b of the forming body 15 and converges at the lower end. Thus, a plate-shaped glass strip G is continuously formed. This continuously formed glass strip G is fed downwards in a longitudinal (preferably vertical) orientation.

[0060] The interior space of the heat treatment zone 12 tends downwards and has a predetermined temperature gradient. The longitudinally oriented glass strip G is heat-treated (annealed) in such a manner that its temperature decreases as it moves downwards within the interior space of the heat treatment zone 12. Through this heat treatment, the internal strain of the glass strip G is reduced. The temperature gradient within the interior space of the heat treatment zone 12 is adjusted, for example, by a heating device provided on the inner surface of the wall of the heat treatment zone 12.

[0061] Multiple roller pairs R constituting the conveying device 14 clamp the two ends of the glass strip G in a longitudinal orientation along its width direction from both sides of the back surface. The uppermost roller pair R located in the forming zone 11 is a cooling roller. It should be noted that, in the internal space of the heat treatment zone 12, etc., the multiple roller pairs R may also include roller pairs that do not clamp the ends of the glass strip G in the width direction. That is, the opposing interval of the roller pairs R may be made larger than the thickness of the ends of the glass strip G in the width direction, allowing the glass strip G to pass between the roller pairs R.

[0062] In this embodiment, the glass strip G manufactured by the processing apparatus 1 has a portion (hereinafter also referred to as "ear") with a thickness greater than that of the central portion in the width direction at both ends due to shrinkage and other effects during the forming process.

[0063] The first cutting device 2 is configured to cut the longitudinally oriented glass strip G to a predetermined length along the width direction below the processing device 1, thereby sequentially cutting glass sheets from the glass strip G. The glass sheets are then processed in a subsequent process to remove the ears, becoming a raw glass sheet (mother glass sheet) from which one or more product glass sheets can be extracted. Here, the width direction is orthogonal to the length direction (transport direction) of the glass strip G, and in this embodiment, it is substantially aligned with the horizontal direction. It should be noted that in the following description, when... Figure 2 When viewing the glass strip G from the rear as shown, the side with arrow X2 in the figure is taken as the left side in the width direction, and the side with arrow Y2 in the figure is taken as the right side in the width direction.

[0064] like Figure 1 as well as Figure 2As shown, the first cutting device 2 includes a breaking device 22. This breaking device 22 is a device that cuts a glass sheet by breaking the glass strip G along the scribe line S at a breaking position P2 located below the scribe line formation position P1. In this embodiment, the breaking device 22 includes a breaking member 23 that abuts against the area where the scribe line S is formed from the second main surface Gb side, and a holding mechanism 24 that holds the lower region of the glass strip G at a position lower than the breaking position P2.

[0065] The breaking member 23 is composed of a plate-like body (platform) having a contact surface (arc-shaped in side view) that contacts the entire area or a portion of the glass strip G in the width direction. The contact surface of the breaking member 23 can also be viewed from above as a curved surface that is bent in the width direction.

[0066] The holding mechanism 24 includes multiple clamps 25 disposed at both ends of the glass strip G in the width direction and in the vertical direction, and arms 26 at both ends in the width direction for holding the multiple clamps 25 respectively (see reference). Figure 2 It should be noted that the clamp 25 can also be changed to other holding methods such as using negative pressure adsorption to hold the glass strip G.

[0067] A scribing forming apparatus 27 is provided above the first cutting device 2. This scribing forming apparatus 27 forms scribing lines S on the first main surface Ga of the glass strip G in a longitudinal orientation as it descends from the processing device 1 at the scribing forming position P1. In this embodiment, the scribing forming apparatus 27 includes: a cutting wheel 28 that forms scribing lines S on the first main surface Ga of the glass strip G along its width direction; and a support member 29 (e.g., a support rod, support roller) that supports the second main surface (the surface opposite to the first main surface Ga) Gb of the glass strip G at a position corresponding to the cutting wheel 28. It should be noted that the scribing lines S are formed by laser irradiation or the like.

[0068] like Figure 3As shown, the first cutting device 2 and the scribing forming device 27 are configured to move between a cutting area E1 (hereinafter referred to as the first cutting area E1) of the transport path GS including the glass strip G and a retraction area F1 (hereinafter referred to as the first retraction area F1) that separates from the transport path GS of the glass strip G in both forward and backward directions. Here, the first retraction area F1 separates from the transport path GS of the glass strip G in both forward and backward directions by a predetermined distance La. This predetermined distance La is, for example, 200 to 1000 mm, preferably 300 to 600 mm. In this embodiment, the first cutting device 2 is configured such that both the breaking member 23 and the holding mechanism 24 move from the first cutting area E1 only relative to the first retraction area F1 in front. In addition, the scribing forming device 27 is configured such that the support member 29 moves from the first cutting area E1 relative to the first retraction area F1 in front, and the cutter wheel 28 moves from the first cutting area E1 relative to the first retraction area F1 in rear.

[0069] Furthermore, a first sensor 30 for detecting the presence or absence (state) of the glass strip G is provided at a constant position above the first cutting device 2 (see reference). Figure 1 as well as Figure 2 In the illustration, the first sensor 30 is positioned behind the transport path GS of the glass belt G, but it can also be positioned in front of the transport path GS. Additionally, the first sensor 30 is positioned above the scribing forming apparatus 27, but it can also be positioned between the first cutting device 2 and the scribing forming apparatus 27.

[0070] In this case, such as Figure 2 As shown, multiple first sensors 30 are provided corresponding to various locations along the width of the glass strip G. In this embodiment, a total of three first sensors 30 are provided at locations corresponding to both ends of the glass strip G along its width and at a location corresponding to the center of the width. These first sensors 30 are fixed to a mounting member (not shown) along a straight line in the width direction. Laser sensors, ultrasonic sensors, or thermal sensors are used as the first sensors 30. It should be noted that the first sensors 30 continuously detect the presence or absence of the glass strip G.

[0071] like Figure 1 as well as Figure 2 As shown, the second cutting device 3 is positioned below the first cutting device 2, and is cut by the glass strip G being transported downwards while the forming zone 11 is being formed during the non-operation of the first cutting device 2 (e.g., during maintenance, when the forming of the glass strip G resumes).

[0072] The second cutting device 3 has a main frame 31 consisting of a frame body located behind the glass strip G. A pair of holding devices 32, a pair of cutting devices 33, and a stress-applying device 34 are sequentially installed from top to bottom at the front end of the main frame 31.

[0073] A pair of retaining devices 32 each has retaining members 36 arranged corresponding to the two ends of the glass strip G in the width direction. The pair of retaining members 36 are respectively rotatable around a rotation axis 37 (see reference). Figure 4 as well as Figure 5 Rotation. Therefore, the pair of retaining members 36 can respectively change as follows: Figure 4 As shown, the glass strip separates outward from both ends in the width direction of G and extends in the front-back direction (in...). Figure 6 (The state represented by the solid line in the middle) and such Figure 5 As shown, the glass band G extends in the left-right direction to maintain the second principal surface Gb of the glass band G (in Figure 6 (The state represented by a single-dot dash).

[0074] Moreover, such as Figure 6 As shown, a pair of retaining members 36 are respectively connected to the front ends of sliding arms 36a that are longer in the front-rear direction via a rotation shaft 37. The pair of sliding arms 36a are held on guide members 36b, which are respectively fixed to the upper ends of the main frame 31, so that they can slide in the front-rear direction. Furthermore, the pair of retaining members 36 are respectively configured as follows... Figure 7 The structure shown moves between a cutting area E2 (hereinafter referred to as the second cutting area E2) of the transport path GS including the glass ribbon G and a retraction area F2 (hereinafter referred to as the second retraction area F2) that separates rearward from the transport path GS of the glass ribbon G. Here, the second retraction area F2 separates rearward from the transport path GS of the glass ribbon G by a predetermined distance Lb. This predetermined distance Lb is, for example, 500 to 2000 mm, preferably 700 to 1500 mm, and is longer than the predetermined distance La mentioned above. These holding members 36 are held at the same height position and can move independently. In this case, the entry of each holding member 36 from the second retraction area F2 to the second cutting area E2 is based on the detection result of the first sensor 30. In addition, the retraction of each holding member 36 from the second cutting area E2 to the second retraction area F2 is also based on the detection result of the first sensor 30. It should be noted that, in this embodiment, the forward and backward movement of each holding member 36 (each sliding arm) is achieved by the action of an off-the-charts drive mechanism (e.g., a cylinder, a ball screw mechanism, etc.), and the action of the drive mechanism is controlled based on the signal from the first sensor 30.

[0075] A pair of cutting devices 33 are equipped with rotating blades 38 respectively arranged corresponding to the two ends of the glass strip G in the width direction. The pair of rotating blades 38 are respectively movable in the front-back direction (in the direction inclined upward towards the front direction) (see reference). Figure 2 as well as Figure 6 Furthermore, the pair of rotating blades 38 can each be transformed into, for example... Figure 4 As shown, the state of retreating backward from the glass strip G (in) Figure 6 The state represented by the solid line in the middle) and such Figure 5 As shown, the glass strip G is pressed at both ends in the width direction (in...). Figure 6 (The state is represented by a single-dot dash). Additionally, the pair of rotating blades 38 can also move in the left and right directions. Furthermore, the pair of rotating blades 38 maintain the same height position and can move and operate independently. When each rotating blade 38 is pressed against the glass strip G, it can perform the process of engraving lines at the width end of the glass strip G and the process of cutting off the width end of the glass strip G.

[0076] The stress-applying device 34 has a pressing member 41 mounted on the front end of a pair of swing arms 40 capable of swinging about a support shaft 39 (see reference). Figure 2 as well as Figure 6 The pressing member 41 is a roller-shaped member extending along the width direction and is longer than the width direction length of the glass strip G. Furthermore, the pressing member 41 can be varied as follows: Figure 4 As shown, the state of retreating backward from the glass strip G (in) Figure 6 The state represented by the solid line in the middle) and such Figure 5 The glass strip G is pressed as shown in the diagram (in the state of pressing the glass strip G). Figure 6 (The state is represented by a single-dot dash). When the pressing member 41 presses down on the glass strip G, it imparts bending stress to the glass strip G (details are described later).

[0077] Moreover, such as Figure 6 As shown, the second cutting device 3 includes a second sensor 35 for detecting the presence or absence of the glass strip G. In the illustration, the second sensor 35 is fixed to the main frame 31 and thus positioned behind the transport path of the glass strip G. Furthermore, the second sensor 35 is positioned at a height between the upper support shaft 39 and the lower pressing member 41 of the stress-applying device 34. In this case, as... Figure 2As shown, multiple second sensors 35 are provided corresponding to various locations along the width of the glass strip G. In this embodiment, a total of three second sensors 35 are provided at locations corresponding to both ends of the glass strip G along its width and at a location corresponding to the center of the width. These second sensors 35 are fixed to the front end of the main frame 31 in a straight line along the width and are held in a constant position. Laser sensors, ultrasonic sensors, or thermal sensors are used as the second sensors 35. It should be noted that the second sensors 35 continuously detect the presence or absence of the glass strip G.

[0078] The manufacturing apparatus performs a switching process to switch the operation of the first cutting device 2 to the operation of the second cutting device 3. In this embodiment, the measure of moving the holding member 36, which is in a state of extending in the front-rear direction, from the second retraction region F2 into the second cutting region E2 is equivalent to the switching process. After the switching process is performed, the glass strip G is cut by the second cutting device 3 while the holding member 36 remains in the second cutting region E2.

[0079] Here, the basic cutting process (hereinafter referred to as the first process) performed by the second cutting device 3 will be described. During the first process, firstly, on the glass strip G... Figure 6As shown by the solid line, a pair of retaining members 36, which are continuously transported downwards, rotate around the rotation axis 37 from their forward-backward extension position. Thus, the pair of retaining members 36 extend in the left-right direction as shown by the dashed line in the figure, and are able to hold the second main surface Gb of the glass strip G. Next, in this state, the pressing member 41 swings forward. Thus, the pressing member 41 presses the glass strip G as shown by the dashed line in the figure, applying bending stress to the periphery of the area Gx to be cut. At this time, the pair of retaining members 36 hold the second main surface Gb of the glass strip G above the area Gx to be cut, preventing the glass strip G from displacing forward. Furthermore, in this state, a pair of rotating blades 38 move forward. Thus, the pair of rotating blades 38 press the first main surface Ga of the glass strip G as shown by the dashed line in the figure, and etch a scribe line (initial crack) on the glass strip G. The initial crack is simultaneously etched by the pair of rotating blades 38 at both ends of the glass strip G in the width direction. It should be noted that, if sufficient bending stress is applied to the periphery of the area Gx to be cut of the glass strip G along its entire width, an initial crack can be made only at one end of the glass strip G in the width direction using one of the rotating blades 38. The initial crack can be made at either the location of the glass strip G including the lugs or the location excluding the lugs. Furthermore, the initial crack propagates along the width direction of the glass strip G, thereby cutting the glass strip G. The cut glass, as unwanted glass Gy, falls downwards and is collected in the recycling area 42. Afterwards, the holding member 36 is again positioned to extend in the front-back direction, ready for subsequent cutting processing. It should be noted that an opening 44 is formed in the floor wall 43 on which the second cutting device 3 is mounted for allowing the cut glass to fall into the recycling area 42.

[0080] This first process is repeated during the operation of the second cutting device 3 while the glass strip G remains undamaged. It should be noted that when the second cutting device 3 is not in operation, the retaining member 36 is retracted to the second retraction area F2 while extending in the front-rear direction.

[0081] The second cutting device 3, in addition to the first cutting process described above, can also perform a second cutting process as shown below. It should be noted that the second cutting process is, for example, a cutting process performed when forming resumes after breakage, where only one end of the glass strip G in the width direction is formed. When performing the second cutting process, firstly, as... Figure 8As shown, when only one end of the glass strip G in the width direction (the left end in the example) G1 is successfully transported to the second cutting area E2, only the holding member 36 corresponding to this end G1 in the width direction rotates from its state of extending in the front-back direction to its state of extending in the left-right direction. At this time, the holding member 36 corresponding to the other end of the glass strip G in the width direction (the right end in the example) does not move. Next, the rotating blade 38 corresponding to the end G1 in the width direction presses down on this end G1 and moves in the left-right direction. As a result, this end G1 in the width direction is cut along the line (straight line) indicated by reference numeral L1 in the figure. At this time, the rotating blade 38 corresponding to the other end of the glass strip G in the width direction (the right end in the example) does not move. It should be noted that this figure illustrates the cutting operation of only the right end G1 in the width direction of the glass strip G, but the cutting operation of only the left end in the width direction of the glass strip G can also be performed in the same way. During this second process, the action of applying bending stress to the glass strip G using the pressing member 41 is not performed.

[0082] Furthermore, the second cutting device 3, in addition to the first and second cutting processes described above, can also perform a third cutting process as shown below. It should be noted that the third cutting process is, for example, a cutting process performed when, after the forming process has restarted following a breakage, only the two ends in the width direction of the glass strip G are formed, without forming the central portion in that width direction. When performing the third cutting process, firstly, as... Figure 9 As shown, when only the two ends G1 and G2 of the glass strip G in the width direction have been successfully transported to the second cutting area E2, the pair of holding members 36 are rotated from their forward-backward extending state to their left-right extending state. Next, the pair of rotating blades 38 press down on the two ends G1 and G2 in the width direction and move in the left-right direction respectively. As a result, the two ends G1 and G2 in the width direction are cut along the lines (straight lines) indicated by reference numerals L1 and L2 in the figure. During this third process, the action of applying bending stress to the glass strip G using the pressing member 41 is not performed.

[0083] In this embodiment, the rotation of each holding member 36 is based on the detection results of the second sensor 35. Specifically, the rotation of each holding member 36 is achieved by the operation of an off-screen drive mechanism (e.g., a motor), the operation of which is controlled based on signals from the second sensor 35. Furthermore, the forward / backward and left / right movements of each rotating blade 38 are also based on the detection results of the second sensor 35. Specifically, the forward / backward and left / right movements of each rotating blade 38 are achieved by the operation of off-screen drive mechanisms (e.g., cylinders, ball screw mechanisms), the operation of which is controlled based on signals from the second sensor 35. Moreover, the movement of the pressing member 41 is also based on the detection results of the second sensor 35. Specifically, the movement of the pressing member 41 is achieved by the operation of an off-screen drive mechanism (e.g., a motor), the operation of which is also controlled based on signals from the second sensor 35.

[0084] Next, a method for manufacturing a glass plate using a glass plate manufacturing apparatus having the structure described above will be explained.

[0085] The glass plate manufacturing method of this embodiment includes a forming process, a handling process, a first cutting process, a first inspection process, a second cutting process, a second inspection process, and a switching process.

[0086] The forming process is the process of forming glass strip G in forming zone 11.

[0087] The transport process involves using the rollers of the transport device 14 to transport the formed glass ribbon G to R. It should be noted that the transport process includes both heat treatment and cooling processes.

[0088] The heat treatment process is a process in which the glass strip G, which has undergone the forming process, is heat-treated in the heat treatment zone 12 at the same time as it is being transported.

[0089] The cooling process is carried out in the cooling zone 13 while the glass strip G that has undergone the heat treatment process is being transported.

[0090] The first cutting process is a process in which the glass strip G, which has undergone the cooling process, is cut along the width direction using the first cutting device 2 to obtain a glass plate.

[0091] If described in detail, such as Figure 1 as well as Figure 2As shown, in the first cutting process, firstly, the cutter wheel 28 and the support member 29 form a scribe line S over the entire area or a portion of the width of the glass strip G while moving in tandem with the glass strip G that moves continuously downwards. In this embodiment, the scribe line S is also formed on the relatively thick ear portion. Next, after the multiple chucks 25 hold the glass strip G, the arm 26 moves the multiple chucks 25 in tandem with the glass strip G. At this time, the breaking member 23 also moves in tandem with the glass strip G. During these movements, the arm 26 performs an action to bend the glass strip G using the breaking member 23 as a fulcrum. Figure 1 (The action is shown in direction B). This imparts bending stress to the scribe line S and its vicinity, causing the glass strip G to break along the scribe line S in the width direction. The result of this breakage is that a glass plate is cut from the glass strip G.

[0092] The first detection process involves using three first sensors (30) to detect the presence or absence of glass strip G.

[0093] The second cutting process is the process of cutting the glass strip G using the second cutting device 3 when the first cutting device 2 is not in operation.

[0094] The second detection process involves using three second sensors 35 to detect the presence or absence of glass strip G.

[0095] The switching process is a process used to switch the first cutting process to the second cutting process based on the detection results in the first detection process. This switching process is performed between the interruption of the first cutting process and the start of the second cutting process.

[0096] In detail, during the first cutting process, or in other words, during the operation of the first cutting device 2, the holding member 36, the rotating blade 38, and the pressing member 41, which are components of the second cutting device 3, remain in place. Figure 7 The second retraction area F2 is shown. On the other hand, during the second cutting process, in other words, during the operation of the second cutting device 3, the retaining member 36 remains in... Figure 7 The second cut-off region E2 is shown.

[0097] Furthermore, when the first detection step detects that the glass strip G is missing due to breakage during the execution of the first cutting step, the first cutting device 2 retracts from the first cutting area E1 to the first retraction area F1. Then, a switching step is performed based on the detection result from the subsequent first detection step. Specifically, in the switching step, the holding member 36, which is in a forward-backward direction, is moved from the second retraction area F2 to the second cutting area E2. After this switching step, the second cutting step is performed. Thus, the first cutting step is interrupted due to breakage, then the holding member 36 enters, and then the second cutting step is performed. In this embodiment, the switching step reduces or eliminates the need for operator intervention, and is performed smoothly through automation.

[0098] In the event of glass strip G breaking, glass fragments fall towards the second cutting area E2, but the retaining member 36 remains in the second retraction area F2. Additionally, the rotating blade 38 and the pressing member 41 also remain in the second retraction area F2. The retaining member 36 enters the second cutting area E2 from the second retraction area F2 earlier than the rotating blade 38 and the pressing member 41. In other words, the retaining member 36 is the first among the components of the second cutting device 3 to enter the second cutting area E2 from the second retraction area F2.

[0099] Next, based on Figures 10-13, the process from the breakage of the glass strip G during the first cutting process to its cutting in the second cutting process will be described. It should be noted that in these figures, the three circles (○) arranged above the first cutting device 2 represent the detection areas 30a of the three first sensors 30, and the three circles (○) arranged in the middle of the vertical direction of the second cutting device 3 represent the detection areas 35a of the three second sensors 35. Furthermore, in the following description, the situation where the first and second sensors 30 and 35 detect the presence of the glass strip G will be described as "on," and the situation where no glass strip G is detected will be described as "off."

[0100] Figure 10a , Figure 10b , Figure 10c The figure illustrates a first example of the above process. This first example illustrates the following situation: during the execution of the first cutting process, after the glass strip G breaks, forming begins again, so that the two ends and the central portion of the glass strip G in the width direction are transported simultaneously with forming, as shown in the figures above. In this case, the glass strip G is transported simultaneously with forming, so that the three first sensors 30 are... Figure 10a The disconnected state is switched to Figure 10bThe switch is shown in the on state. After this switch, after a predetermined short time (e.g., 0.3 to 0.8 seconds, preferably 0.5 seconds), a pair of retaining members 36 are brought into the second cutting region E2. Here, the predetermined short time is the time required to ensure that the glass strip G formed and transported after the first sensor 30 is switched on is not broken and continues to be detected by the first sensor 30. Therefore, even if the pair of retaining members 36 are brought into the second cutting region E2 at this moment, there will be no situation where broken glass pieces or the like collide with these retaining members 36.

[0101] The glass ribbon G is transported while being further shaped, and as... Figure 10c When the three second sensors 35 switch from off to on as shown, the following operation is performed. That is, after a preset time has elapsed since the three second sensors 35 switched on, the glass strip G is cut by the first process described above, performed by the second cutting device 3. It should be noted that the preset time here is the time required from the time the second sensors 35 switch on until the entire area of ​​the lower end Gz of the glass strip G has been moved downward by a predetermined distance compared to the pressing member 41.

[0102] Figure 11a , Figure 11b , Figure 11c The diagram illustrates a second example of the above process. This second example illustrates the following situation: after the glass strip G cracks or otherwise breaks during the first cutting process, forming begins again, so that, as shown in the above figures, the left end and the center portion of the glass strip G in the width direction are formed and transported first, and the right end in the width direction is subsequently formed and transported. In this case, the glass strip G is transported while being formed, so that, firstly as shown in the figures above, the left end and the center portion in the width direction are formed and transported, and then the right end in the width direction is formed and transported. Figure 11a As shown, the first sensor 30 at the left end and center is turned on, while the first sensor 30 at the right end is turned off. When both first sensors 30 are turned on, only the holding member 36 on the left side enters the second cutting-off region E2. When... Figure 11a When the glass ribbon G is formed as shown, the vertical length of the defect Gw located on the right side of the lower end Gz of the glass ribbon G is usually short, as shown in the figure. Therefore, in this case, as... Figure 11b As shown, soon after, the three first sensors 30 become switched on. At this moment, the right-side retaining member 36 is moved into the second cutting region E2. Similarly, in this case, if the first sensor 30, which became switched on after the left-side retaining member 36 was moved in, becomes switched off again, the same countermeasures as in the first example described above are taken. Furthermore, the glass strip G is transported downwards while being further formed, thus... Figure 11cWhen the three second sensors 35 switch from off to on as shown, after a preset time has elapsed, the glass strip G is cut by the first process described above, performed by the second cutting device 3. It should be noted that when the forming of the glass strip G resumes here, even if the right end and the center portion in the width direction of the glass strip G are formed and transported first, and the left end in the width direction is subsequently formed and transported, the glass strip G can be cut in the same order.

[0103] In the second example above, when both first sensors 30 are turned on, only one side of the holding member 36 is allowed to enter the second cut-off region E2. However, it is also possible that when both first sensors 30 are turned on, the holding member 36 on one side is not allowed to enter the second cut-off region E2, but when all three first sensors 30 are turned on, the holding members 36 on both sides are allowed to enter the second cut-off region E2.

[0104] Figure 12a , Figure 12b The figure illustrates a third example of the above process. This third example illustrates the handling of a situation where, during the execution of the first cutting process, forming resumes after the glass strip G has broken, so that, as shown in the figures above, only the left end G1 in the width direction of the glass strip G is transported during forming. In this case, the left end G1 in the width direction of the glass strip G is transported during forming, so that, firstly as shown in the figures above... Figure 12a As shown, the first sensor 30 at the left end is turned on, while the first sensors 30 at the center and right end are turned off. When the first sensor 30 at the left end is turned on, only the left-side retaining member 36 is brought into the second cutting region E2. Similarly, in this case, if the first sensor 30 at the left end turns off again after the left-side retaining member 36 has been brought in, the left-side retaining member 36 is retracted and brought in using the same method as in the first example described above. Furthermore, the left end G1 in the width direction of the glass strip G is further formed and transported downwards, as shown... Figure 12b When the second sensor 35 on the left side switches from off to on as shown, after a preset time has elapsed, the left end G1 of the glass strip G is cut off by the second process described above, performed by the second cutting device 3. It should be noted that when the forming of the glass strip G resumes here, even if only the right end of the glass strip G in the width direction is transported during forming, the right end of the glass strip G in the width direction can be cut off in the same order using the holding member 36 on the right side.

[0105] Figure 13a , Figure 13bThe diagram illustrates a fourth example of the above process. This fourth example illustrates the handling of a situation where, during the execution of the first cutting process, forming begins again after the glass strip G breaks, so that, as shown in the above figures, the left end G1 and the right end G2 in the width direction of the glass strip G are transported simultaneously during forming. In this case, both ends G1 and G2 in the width direction of the glass strip G are transported simultaneously during forming, so that, firstly as shown in the figures... Figure 13a As shown, the first sensors 30 at the left and right ends are turned on, while the first sensor 30 at the center is turned off. When the first sensors 30 at the left and right ends are turned on, a pair of retaining members 36 are brought into the second cutting region E2. Similarly, in this case, if at least one of the first sensors 30 at the left and right ends is turned off again after the pair of retaining members 36 have been brought in, the corresponding retaining member 36 is retracted and brought in using the same method as in the first example described above. Furthermore, the left end G1 and the right end G2 in the width direction of the glass strip G are transported downwards while being further shaped, and as... Figure 13b When the second sensor 35 at the left and right ends, as shown, switches from off to on, after the preset time has elapsed, the left end G1 and the right end G2 of the glass strip G in the width direction are cut off by the third process described above, performed by the second cutting device 3.

[0106] In the first to fourth examples above, the three first sensors 30 continuously detect the presence or absence of the glass strip G. Therefore, based on the detection results obtained by the first sensors 30 in the first detection process, it is possible to identify the following states: a first state in which either end of the glass strip G in the width direction is transported during forming; a second state in which either end of the glass strip G in the width direction and the central portion in the width direction are transported during forming; a third state in which both ends of the glass strip G in the width direction are transported during forming; and a fourth state in which the entire width direction of the glass strip G is transported during forming.

[0107] The first to fourth examples above illustrate the use of three first sensors 30 and three second sensors 35 to cut the glass strip G, but it is also possible to cut the glass strip G using only two first sensors 30 and two second sensors 35. In this case, for any of the three first sensors 30 and three second sensors 35, the central sensors 30 and 35 can be eliminated, and the left and right sensors 30 and 35 can be used respectively. In this case, either three first sensors can be used for the first sensor 30 and the left and right second sensors can be used for the second sensor 35, or the left and right first sensors can be used for the first sensor 30 and three second sensors can be used for the second sensor 35.

[0108] The glass plate manufacturing apparatus and manufacturing method according to the embodiments of the present invention have been described above. However, 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.

[0109] In the above embodiment, the glass strip G is formed by overflow pull-down method, but it can also be formed by other pull-down methods such as slit pull-down method or re-pull method.

[0110] In the above embodiment, in the first cutting process, the glass strip G is cut by breaking along the scribing line S, but other methods such as laser cutting or laser melting can also be used for cutting.

[0111] In the above embodiment, a second cutting device 3 is disposed below the first cutting device 2, but the two devices 2 and 3 may also be disposed side by side in a manner in which part or all of them are in the same position in the vertical direction. In such a case, the main frame 31 of the second cutting device 3 is kept in a constant position, and when the first cutting device 2 is used, the holding member 36, the rotating blade 38, and the pressing member 41 are retracted to a position that does not obstruct the operation of the first cutting device 2. Alternatively, the first cutting device 2 and the second cutting device 3 may be mounted (installed) on the same floor wall 23.

[0112] In the above embodiment, the main frame 31 of the second cutting device 3 is not moved, but the holding member 36, the rotating blade 38 and the pressing member 41 are moved in and out. However, these members 36, 38 and 41 can also be moved in and out while the main frame 31 is moved in the front-back direction.

[0113] In the above embodiment, a rotating blade 38 is used to cut the glass strip G, but any other cutting blade can be used as long as it has a cutting edge.

[0114] In the above embodiments, two or three first and second sensors 30 and 35 are arranged along the width direction, but four or more first and second sensors 30 and 35 may also be arranged along the width direction.

[0115] In the above embodiment, the holding member 36 is brought in during the switching process. However, if the structure of the second cutting device 6 differs from the above embodiment, other components of the second cutting device (especially the components that first enter the second cutting region E1 from the second retraction region F2) may also be brought in. Furthermore, if the mechanism for switching the first cutting process to the second cutting process is not the mechanism for bringing in the components of the second cutting device 6, the switching process may be performed using a mechanism that does not accompany the bringing in operation.

[0116] Explanation of reference numerals in the attached figures

[0117] 1. Glass ribbon processing device

[0118] 2 First cutting device

[0119] 3 Second cutting device

[0120] 11 Forming Zone

[0121] 30 First Sensor

[0122] 31 Main Framework

[0123] 32 Holding device

[0124] 34 Stress-Applying Device

[0125] 35 Second Sensor

[0126] 36 retaining components

[0127] 38 Rotary Blade (Cutting Blade)

[0128] 41 Pressing component

[0129] E1 First Cutting Zone

[0130] E2 Second Cut-off Zone

[0131] F1 First Retreat Zone

[0132] F2 Second Retreat Zone

[0133] G glass ribbon

[0134] The transport path of GS glass ribbon.

Claims

1. A method for manufacturing a glass plate, comprising: In the first cutting process, a glass sheet is cut out by using a first cutting device to cut the glass belt that is being transported while being formed. And a second cutting process, wherein the glass strip is cut using a second cutting device when the first cutting device is not in operation. The method for manufacturing the glass plate is characterized in that, The method for manufacturing the glass plate includes a first detection step that uses a sensor to detect the presence or absence of a glass strip at a position upstream of the first cutting device and the second cutting device in the transport direction, and a switching step that switches the first cutting step to the second cutting step if the absence of the glass strip is detected in the first detection step.

2. The method for manufacturing a glass plate according to claim 1, wherein, The sensor is respectively disposed at multiple locations along the width direction of the glass strip.

3. The method for manufacturing a glass plate according to claim 1 or 2, wherein, The sensor is respectively disposed corresponding to at least both ends and the middle part of the glass strip in the width direction, and is able to identify, based on the detection results in the first detection process, a first state in which either end of the glass strip in the width direction is transported during forming, a second state in which either end of the glass strip in the width direction and the middle part in the width direction are transported during forming, a third state in which both ends of the glass strip in the width direction are transported during forming, and a fourth state in which the entire width direction of the glass strip is transported during forming.

4. The method for manufacturing a glass plate according to claim 1 or 2, wherein, In the switching process, if the glass strip is not detected in the first detection process, the components of the second cutting device are moved from the retraction area to the cutting area.

5. The method for manufacturing a glass plate according to claim 4, wherein, The component of the second cutting device is a part of all the components of the second cutting device and is the first component to enter when the cutting process by the second cutting device begins.

6. The method for manufacturing a glass plate according to claim 5, wherein, The sensor is respectively disposed corresponding to at least both ends of the glass strip in the width direction. The earliest entering component is any one or both of the holding members used to hold both ends of the glass strip in the width direction during the cutting process in the second cutting process, so that the holding member corresponding to the end of the glass strip in the width direction detected by the sensor enters, and the holding member corresponding to the end of the glass strip in the width direction detected by the sensor does not enter.

7. The method for manufacturing a glass plate according to claim 4, wherein, The method for manufacturing the glass sheet further includes a second detection step in which the presence or absence of the glass strip is detected by sensors provided at a position downstream of the sensor used in the first detection step in the transport direction, corresponding to at least both ends of the glass strip in the width direction, and a cutting process is performed on the glass strip using the components of the second cutting device that entered in the switching step based on the detection results of these sensors.

8. The method for manufacturing a glass plate according to claim 7, wherein, The second cutting device comprises a cutting blade used for cutting the glass strip, and the cutting blade is pressed against the glass strip based on the detection results in the second detection process.

9. The method for manufacturing a glass plate according to claim 8, wherein, The second cutting device comprises a pressing member that applies stress to the glass strip, and applies stress to the glass strip by the pressing member based on the detection results in the second detection process.

10. A glass sheet manufacturing apparatus comprising: a first cutting device for cutting a glass sheet by cutting a glass strip being transported during forming; and a second cutting device for cutting the glass strip when the first cutting device is not in operation. The glass plate manufacturing apparatus is characterized in that, The glass plate manufacturing apparatus includes a sensor that detects the presence or absence of the glass strip at a position upstream of the first cutting device and the second cutting device in the transport direction, and is configured to perform a switching process to switch the operation of the first cutting device to the operation of the second cutting device when the sensor detects that the glass strip is absent.

Images