Manufacturing method of wedge-shaped glass

Abstract

The present invention involves: cutting a glass material sheet along a lateral cutting line by applying a bending stress to the glass material sheet using a lateral cleaving machine to form a glass member; cutting the glass member along a longitudinal cutting line by applying a bending stress to the glass member using a longitudinal cutting machine; separating unnecessary portions to form a wedge-shaped glass product portion; detecting a wedge angle at a management position X of the glass product portion by an inspection device; and controlling the position in the width direction of the longitudinal cutting line formed by the longitudinal cutting machine on the basis of the wedge angle at the management position X, to control the wedge angle at the management position X so that the difference between said wedge angle and a predetermined ideal wedge angle at the management position X falls within a predetermined range.

Description

[Technical Field]

[0001] This invention relates to a method for manufacturing wedge-shaped glass. [Background technology]

[0002] Flat glass manufactured by the float process is generally flat with little variation in thickness. However, in the case of windshields equipped with a head-up display (HUD) that displays information on the windshield of a car, for example, it is known that using wedge-shaped glass with varying thicknesses can reduce the double image that drivers experience when viewing the scenery outside the car or the information displayed on the HUD.

[0003] As a method for manufacturing wedge-shaped glass, a method has been considered in which multiple top rolls are brought into contact with one end of a glass ribbon moving on a molten metal bath (float bath), forming a glass sheet with a convex, concave, or tapered cross-section in the width direction perpendicular to the direction of movement, and then cutting the glass sheet to obtain a wedge-shaped glass product (see, for example, Patent Documents 1 to 3). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2016 / 117650 [Patent Document 2] Japanese Patent Publication No. 2019-73509 [Patent Document 3] U.S. Patent No. 7122242 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Incidentally, if the glass ribbon meanders during the manufacturing process of wedge-shaped glass, the position of the glass sheet in the width direction fluctuates. As a result, the position in the width direction at which the glass sheet is cut also fluctuates, and the wedge angle and thickness of the resulting glass product also fluctuate. This makes it impossible to maintain the wedge angle of the wedge-shaped glass within a predetermined range. In particular, if the wedge angle in the area of ​​the wedge-shaped glass used as a HUD (hereinafter sometimes referred to as the HUD display area) cannot be kept within a predetermined range, it becomes impossible to effectively suppress double images in the HUD display area.

[0006] This invention has been made in view of these circumstances, and aims to provide a method for manufacturing wedge-shaped glass in which the wedge angle of wedge-shaped glass cut from a glass sheet is kept within a predetermined range. [Means for solving the problem]

[0007] The present invention provides a method for manufacturing wedge-shaped glass, characterized in that a glass sheet having a thickness variation along its width is conveyed by a plurality of conveyor rolls, a vertical cut line is formed in the longitudinal direction of the glass sheet by a vertical cutter, a horizontal cut line is formed in the width direction of the glass sheet by a horizontal cutter, bending stress is applied to the glass sheet by a horizontal folding machine to cut the glass sheet along the horizontal cut line and form a glass member, bending stress is applied to the glass member by a vertical folding machine to cut the glass member along the vertical cut line, separating the unnecessary portion and forming a wedge-shaped glass product, the wedge angle at a control position X of the glass product is detected by an inspection device, and the position in the width direction of the vertical cut line formed by the vertical cutter is controlled based on the wedge angle at the control position X, thereby controlling the wedge angle at the control position X so that the difference from a predetermined ideal wedge angle at the control position X is within a predetermined range. [Effects of the Invention]

[0008] According to the present invention, the vertical cutting machine can be controlled based on the wedge angle at the control position X. Therefore, a wedge-shaped glass product portion can be cut from an appropriate position on the glass sheet so that the wedge angle at the control position X is within a predetermined range. [Brief explanation of the drawing]

[0009] [Figure 1] Figures 1(a) to 1(c) are cross-sectional views in the width direction of a glass substrate for wedge-shaped glass, with Figure 1(a) being an example of a convex shape, Figure 1(b) being an example of a concave shape, and Figure 1(c) being an example of a tapered shape. [Figure 2] Figure 2 is a plan view showing a first embodiment of the wedge-shaped glass manufacturing method. [Figure 3] Figure 3 is a plan view showing a second embodiment of the wedge-shaped glass manufacturing method. [Figure 4A] Figure 4A is a plan view showing the method for detecting the wedge angle at control position X. [Figure 4B] Figure 4B is a plan view showing the method for detecting the wedge angle at control position X. [Figure 4C] Figure 4C is a plan view showing the method for detecting the wedge angle at control position X. [Modes for carrying out the invention]

[0010] The first and second embodiments of the present invention will be described below, but the present invention is not limited to the embodiments described below. Many modifications can be made without departing from the scope of the present invention.

[0011] [First Embodiment] Figures 1(a) to 1(c) are cross-sectional views in the width direction of a glass sheet for wedge-shaped glass, with Figure 1(a) being an example of a convex shape, Figure 1(b) being an example of a concave shape, and Figure 1(c) being an example of a tapered shape. Figure 2 is a plan view showing a first embodiment of the wedge-shaped glass manufacturing method. The glass sheet 10 is continuously conveyed in the wedge-shaped glass manufacturing apparatus 100, where it is cut and inspected to become wedge-shaped glass product parts 11A and 11B.

[0012] <Raw glass sheet> The raw glass sheet 10 shown in Fig. 2 has a thickness change portion along the width direction of the raw glass sheet 10, that is, the B direction (hereinafter sometimes simply referred to as the width direction). The thickness change portion of the raw glass sheet 10 can be formed, for example, by bringing a plurality of top rolls into contact with one end of a glass ribbon traveling on a molten metal bath (float bath) and adjusting the peripheral speed and pressing force of the top rolls. The thickness change portion can also be adjusted according to the temperature distribution in the width direction of the glass ribbon and the traveling speed of the glass ribbon.

[0013] The cross section of the raw glass sheet 10 in the width direction is convex as shown in Fig. 1(a). The raw glass sheet 10 is composed of ear portions 12A and 12B located on both sides in the width direction, a central portion 13 including the region with the thickest thickness, a first glass product portion 11A located between the ear portion 12A and the central portion 13, and a second glass product portion 11B located between the ear portion 12B and the central portion 13. The glass product portions 11A and 11B are the portions that finally become products.

[0014] The raw glass sheet may be a raw glass sheet 20 whose cross section in the width direction is concave as shown in Fig. 1(b). The raw glass sheet 20 is composed of ear portions 22A and 22B located on both sides in the width direction, a central portion 23 including the region with the thinnest thickness, a first glass product portion 21A located between the ear portion 22A and the central portion 23, and a second glass product portion 21B located between the ear portion 22B and the central portion 23.

[0015] The raw glass sheet may be a raw glass sheet 30 whose cross section in the width direction is tapered as shown in Fig. 1(c). The raw glass sheet 30 is composed of ear portions 32A and 32B located on both sides in the width direction and a glass product portion 31 located between the ear portion's 32A and 32B. In the cross section of the raw glass sheet 30 in the width direction, it is not necessarily the case that all regions are tapered, and only some regions may be tapered.

[0016] The following describes an embodiment using a glass sheet 10, but the same can be implemented with a glass sheet 20 or a glass sheet 30. In that case, the glass product portions 11A and 11B of the glass sheet 10 correspond to the glass product portions 21A and 21B of the glass sheet 20 and the glass product portion 31 of the glass sheet 30. The edges 12A and 12B of the glass sheet 10 correspond to the edges 22A and 22B of the glass sheet 20 and the edges 32A and 32B of the glass sheet 30. The central portion 13 of the glass sheet 10 corresponds to the central portion 23 of the glass sheet 20.

[0017] <Conveyor Roll> A glass sheet 10, which is formed to have a thickness variation in the width direction, is conveyed in the longitudinal direction of the glass sheet 10, that is, direction A (hereinafter sometimes simply referred to as the longitudinal direction), by a plurality of conveyor rolls 110 shown in Figure 2. The conveyor rolls 110 are arranged at a constant pitch distance along the conveyor path and are rotated by a rotary drive means (not shown).

[0018] <Vertical cutting machine> The glass sheet 10, which is conveyed by the conveyor roll 110, has longitudinal cut lines L1 to L4 formed in the longitudinal direction by the longitudinal cutting machine 120 shown in Figure 2.

[0019] The vertical slashes L1 to L4 are scribe lines for separating the glass plate 10 into the glass product parts 11A and 11B, the ear parts 12A and 12B, and the central part 13. Vertical slash L1 is formed at the boundary between the glass product part 11A and the ear part 12A. Vertical slash L2 is formed at the boundary between the glass product part 11B and the ear part 12B. Vertical slash L3 is formed at the boundary between the glass product part 11A and the central part 13. Vertical slash L4 is formed at the boundary between the glass product part 11B and the central part 13.

[0020] The vertical cutting machine 120 is capable of moving back and forth in the thickness direction of the glass sheet, i.e., the C direction (hereinafter sometimes simply referred to as the thickness direction), and in the width direction, and is equipped with multiple cutters 121. By advancing each cutter 121 toward the main surface of the glass (in the opposite direction to the C direction), the cutters 121 come into contact with the glass sheet 10 with a specified pressing force, and vertical cut lines L1 to L4 are processed on the glass sheet 10.

[0021] The positions of the vertical cut lines L1 to L4 in the glass sheet 10 in the width direction can be controlled by adjusting the position of each cutter 121 in the width direction.

[0022] <Transverse machine> After the glass sheet 10, which is conveyed by the conveyor roll 110, has vertical cut lines L1 to L4 formed on it, a horizontal cut line L5 is formed in the width direction by the cross-cutting machine 130 shown in Figure 2.

[0023] The crosscut line L5 is a scribe line for cutting out the glass component 10P from the glass sheet 10.

[0024] The crosscutting machine 130 is equipped with a cutter 131 that can move back and forth in the thickness direction (direction C) and in a plane direction perpendicular to the thickness direction. By advancing the cutter 131 toward the main surface of the glass (in the opposite direction to direction C), the cutter 131 comes into contact with the glass sheet 10 with a specified pressing force. By moving the contacted cutter 131 obliquely in the longitudinal direction in synchronization with the transport speed of the glass sheet 10, a crosscut line L5 is processed in the width direction of the glass sheet 10.

[0025] <Horizontal folding machine> The glass sheet 10, which is conveyed by the conveyor roll 110, has a transverse cut line L5 formed on it. Then, bending stress is applied by the transverse folding machine 140 shown in Figure 2, and the sheet is folded along the transverse cut line L5, thereby cutting out the glass member 10P.

[0026] The transverse folding machine 140 is equipped with a pressing roll (not shown) that can move back and forth in the thickness direction of the sheet. The transverse folding machine 140 presses the glass sheet 10 from below with the pressing roll, applying bending stress along the longitudinal direction with the transverse cut line L5 as the center, and folding the glass sheet 10 along the transverse cut line L5. This cuts out the glass member 10P from the glass sheet 10.

[0027] The glass component 10P cut from the glass sheet 10 is moved from the transport roll 110 to a transport roll 111 which has a shorter width than the transport roll 110.

[0028] <First vertical folding machine> The glass member 10P, which is conveyed by a conveyor roll 111 with a short width, is subjected to bending stress by the first vertical folding machine 150 shown in Figure 2, and is folded along the vertical cutting lines L1 and L2, thereby separating the tabs 12A and 12B, and cutting out a glass member 10Q without tabs.

[0029] The first vertical folding machine 150 includes a support roll that supports the edges 12A and 12B of the glass member 10P from below in the C direction, and a pressing projection that presses from above (not shown). The pressing projection and the support roll are movable in the width direction. The support roll is also rotatable in the longitudinal direction.

[0030] The first vertical folding machine 150 supports the ear portions 12A and 12B from below in the C direction with support rolls and applies bending stress along the width direction by pressing them from above in the C direction with pressing projections, thereby folding the ear portions 12A and 12B along the vertical cutting lines L1 and L2. This cuts out a glass member 10Q without ear portions from the glass member 10P.

[0031] The widthwise position at which the first vertical folding machine 150 applies bending stress to the glass sheet 10 can be controlled by adjusting the widthwise positions of the support rolls and pressing protrusions.

[0032] The ear portions 12A and 12B separated from the glass member 10P are considered unnecessary and can be removed from the transport path by being pulled under the transport roll 111, which has a shorter width. On the other hand, the glass member 10Q, which has been cut from the glass member 10P and does not have ear portions, is moved from the transport roll 111, which has a shorter width, to the transport roll 110.

[0033] <Second vertical folding machine> The glass member 10Q, which does not have a tab and is conveyed by the conveyor roll 110, is subjected to bending stress by the second vertical folding machine 160 shown in Figure 2, and is folded along the vertical cutting lines L3 and L4, thereby dividing it into glass product parts 11A and 11B and the unnecessary central part 13.

[0034] The second vertical folding machine 160 is equipped with a pressing roll (not shown) that can move back and forth in the thickness direction and in the width direction. The second vertical folding machine 160 presses the glass member 10Q, which does not have a tab, from below with the pressing roll, applying bending stress along the width direction with the vertical cutting lines L3 and L4 as the center, and folding along the vertical cutting lines L3 and L4. In this way, glass product parts 11A and 11B are cut out from the glass member 10Q, which does not have a tab.

[0035] The widthwise position at which the second vertical folding machine 160 applies bending stress to the glass sheet 10 can be controlled by adjusting the widthwise position of the pressing roll.

[0036] <Separator> The glass product sections 11A and 11B, which are cut from the glass member 10Q without ear sections, and the central section 13 are separated in the width direction by the separation device 170 shown in Figure 2.

[0037] The separating device 170 is positioned between the two transport rolls 110 and is equipped with a separating roll or separating projection (not shown). The glass product sections 11A and 11B and the central section 13 pass over the separating roll or separating projection, thereby widening the gap between the components.

[0038] The widthwise positions of the glass product sections 11A and 11B after passing through the separator device 170 can be controlled by adjusting the position of the separator roll or separator projection.

[0039] <Inspection equipment> The glass product sections 11A and 11B, which pass through the separator device 170 and are transported by the transport roll 110, have their wedge angle at the control position X detected by the inspection device 180 shown in Figure 2.

[0040] Figure 4A is a plan view showing the wedge angle detection method for control position X. As shown in Figure 4A, the control position X of the glass product section 11A is located at a predetermined distance from one end E1 of the glass product section 11A. Similarly, the control position X of the glass product section 11B is located at a predetermined distance from one end E2 of the glass product section 11B.

[0041] The wedge angle at control position X of the glass product sections 11A and 11B is calculated from the thickness at control position Y, which is moved in the width direction from control position X, the thickness at control position Z, which is moved in the width direction opposite to control position Y from control position X, and the distance in the width direction between control position Y and control position Z.

[0042] When control position X is located at the midpoint of control position Y and control position Z, the wedge angle δ at control position X is calculated from the following relation (1).

[0043]

number

[0044] δ: Wedge angle at control position X (unit: mrad) T Y : Thickness of the glass product at control position Y (unit: mm) T Z : Thickness of the glass product at control position Z (unit: mm) d: Distance in the width direction between control position Y and control position Z (unit: mm)

[0045] As shown in Figure 4A, the inspection device 180 includes four plate thickness measuring devices 181 that are movable in the width direction, and a sensor 182. The sensor 182 identifies the width direction positions of one end E1 of the glass product section 11A and one end E2 of the glass product section 11B. Based on the positions of ends E1 and E2, each plate thickness measuring device 181 is moved to the vicinity of control positions Y and Z of the glass product sections 11A and 11B, respectively, and the plate thickness at each control position is measured. As a result, the wedge angle at control position X of the glass product sections 11A and 11B is calculated.

[0046] Here, the wedge angle of the glass product section 11A (or 11B) at the control position X, detected by the inspection device 180 while being transported by the transport roll 110, is preferably within plus or minus 0.1 mrad of the actual wedge angle of the glass product section 11A (or 11B) at the control position X, which is detected when the movement of the glass product section 11A (or 11B) by the transport roll 110 is stopped. Within plus or minus 0.1 mrad, the measurement accuracy of the wedge angle during transport can be maintained. The difference between the wedge angle and the actual wedge angle is more preferably within plus or minus 0.05 mrad, and even more preferably within plus or minus 0.03 mrad. This can also be applied to the second embodiment.

[0047] The distance in the width direction between control position Y and control position Z is preferably 50 mm or more and 250 mm or less. If it is 50 mm or more, measurement errors due to vibrations transmitted from the conveyor roll 110 can be suppressed. If it is 250 mm or less, control positions Y and Z, where the plate thickness is measured, are located close to control position X, so the wedge angle at control position X can be calculated with high accuracy. The distance in the width direction between control position Y and control position Z is more preferably 70 mm or more and 230 mm or less. The distance in the width direction between control position Y and control position Z is appropriately selected according to the pitch distance and conveying speed of the conveyor roll 110. This can also be applied to the second embodiment.

[0048] When the glass product section 11A or 11B is installed as the windshield or window glass of a vehicle and used as a head-up display, the management position X is preferably located within the head-up display area (hereinafter sometimes referred to as the HUD display area), and more preferably located in the center of the head-up display area. This also applies to the second embodiment.

[0049] The HUD display area is a display area that displays information by reflecting projected images from inside the vehicle. The HUD display area is defined as the range in which light from the mirrors constituting the HUD is projected onto the windshield when viewed from point V1 as defined in JIS R3212:2015, by rotating the mirrors that make up the HUD placed inside the vehicle.

[0050] By controlling the wedge-shaped glass manufacturing apparatus 100 based on the wedge angle of the management position X located within the HUD display area, the control device 190 improves the accuracy of maintaining the wedge angle within the HUD display area within a predetermined range.

[0051] <Control device> The wedge angle at control position X, calculated by the inspection device 180, is transmitted to the control device 190 shown in Figure 2. The control device 190 controls the wedge-shaped glass manufacturing apparatus 100 based on the transmitted wedge angle trend, thereby controlling the wedge angle at control position X so that the difference from the predetermined ideal wedge angle at control position X is within a predetermined range. Here, the wedge angle trend refers to the time change of the wedge angle transmitted to the control device 190.

[0052] The control device 190 changes the widthwise positions of the vertical cutting lines L1 to L4 based on the increase or decrease in the wedge angle at the control position X. The widthwise positions of the vertical cutting lines L1 to L4 can be moved by the control device 190 by changing the widthwise position of each cutter 121 provided by the vertical cutting machine 120. This makes it possible to cut out the glass product parts 11A and 11B from appropriate positions on the glass sheet 10 so that the wedge angle at the control position X approaches the ideal wedge angle.

[0053] Preferably, the control device 190 changes the widthwise position in which the first vertical folding machine 150 and the second vertical folding machine 160 apply bending stress based on the transmitted wedge angle trend and the change in the position of the vertical cutting line. The widthwise position of the bending stress applied by the first vertical folding machine 150 can be moved by changing the widthwise position of the pressing projection and support rolls provided on the first vertical folding machine 150. The widthwise position of the bending stress applied by the second vertical folding machine 160 can be moved by changing the widthwise position of the pressing rolls provided on the second vertical folding machine 160. This makes it possible to cut out the glass product parts 11A and 11B from appropriate positions on the glass sheet 10 with higher precision.

[0054] The control device 190 may control the separator device 170 based on the wedge angle at the management position X. Furthermore, the control device 190 may change the position of the separating roll or separating projection provided by the separating device 170 based on the transmitted wedge angle trend and the change in the position of the vertical cutting line. This makes it possible to appropriately adjust the widthwise position of the glass product sections 11A and 11B on the conveying roll 110 after passing through the separating device 170.

[0055] The control device 190 controls the wedge angle at the control position X of the glass product sections 11A and 11B so that the difference from the ideal wedge angle at a predetermined control position X is within a predetermined range. Preferably, the difference from the ideal wedge angle is controlled to be within ±0.1 mrad, more preferably within ±0.05 mrad, and even more preferably within ±0.03 mrad. This can also be applied to the second embodiment.

[0056] When the management position X is located within the HUD display area, the control device 190 preferably controls the wedge-shaped glass manufacturing apparatus 100 so that the wedge angle of the glass product sections 11A and 11B within the HUD display area is 0.2 mrad or more and 1.5 mrad or less, more preferably 0.2 mrad or more and 0.9 mrad or less, and even more preferably 0.3 mrad or more and 0.8 mrad or less. This can also be applied to the second embodiment.

[0057] If the wedge angle within the HUD display area of ​​the glass product sections 11A and 11B is between 0.2 mrad and 1.5 mrad, double images will be reduced; if it is between 0.2 mrad and 0.9 mrad, double images will be suppressed to a level that is hardly a problem in the market; and if it is between 0.3 mrad and 0.8 mrad, double images will be suppressed to a level below the resolution required for the minimum visual acuity of 0.7 needed for a regular driver's license.

[0058] When the wedge-shaped glass obtained as glass product parts 11A and 11B is used, for example, as a windshield of an automobile, the optimal wedge angle of the HUD display area is selected depending on the mounting angle of the windshield and the mounting angle and position of the illuminator that displays information on the windshield.

[0059] [Second Embodiment] Figure 3 is a plan view showing a second embodiment of the wedge-shaped glass manufacturing method. In the same manner as in the first embodiment, a glass sheet 10 formed to have a thickness variation in the width direction is continuously conveyed in the wedge-shaped glass manufacturing apparatus 200, where it is cut and inspected to become wedge-shaped glass product parts 11A and 11B.

[0060] The wedge-shaped glass manufacturing apparatus 200 shown in Figure 3 comprises a main transport path 201 and a secondary transport path 202 connected perpendicularly to the main transport path 201. The wedge-shaped glass manufacturing apparatus 200 may also be equipped with secondary transport paths other than the secondary transport path 202.

[0061] <Conveyor Roll> The glass sheet 10 is transported by a plurality of transport rolls 210 as shown in Figure 3. The plurality of transport rolls 210 are arranged at a constant pitch distance along the longitudinal direction (direction A) of the glass sheet in the main transport path 201. On the other hand, in the secondary transport path 202, they are arranged at a constant pitch distance along the width direction (direction B) of the glass sheet 10.

[0062] In the main transport path 201, similar to the first embodiment, the vertical cutter 220 forms vertical cut lines L1 to L4 on the glass sheet 10, the horizontal cutter 230 forms a horizontal cut line L5 on the glass sheet 10, the horizontal folding machine 240 cuts out the glass member 10P from the glass sheet 10, moves it to a transport roll 211 which is shorter in width than the transport roll 210, and the first vertical folding machine 250 cuts out the glass member 10Q without the tabs from the glass member 10P, and the tabs 12A and 12B are removed from the transport path as unnecessary parts. The vertical cutter 220, horizontal cutter 230, horizontal folding machine 240, and first vertical folding machine 250 may be the same as, for example, the vertical cutter 120, horizontal cutter 130, horizontal folding machine 140, and first vertical folding machine 150 of the first embodiment.

[0063] <Second vertical folding machine> The glass member 10Q, which does not have tabs, moves from the conveyor roll 211, which has a short widthwise length, on the main conveyor path 201, to the conveyor roll 210 on the sub-conveyor path 202, and is conveyed in the widthwise direction. Then, the glass member 10Q, which does not have tabs, is subjected to bending stress by the second vertical folding machine 260 and is folded along the vertical cutting lines L3 and L4, thereby separating it into the glass product parts 11A and 11B and the unnecessary central part 13.

[0064] The second vertical folding machine 260 is equipped with a pressing roll (not shown) that can move back and forth in the thickness direction of the sheet. The second vertical folding machine 260 presses the glass sheet 10 from below the glass member 10Q without edges with the pressing roll, applying bending stress along the width direction with the vertical cut lines L3 and L4 as the centers, and folding along the vertical cut lines L3 and L4. In this way, glass product parts 11A and 11B are cut out from the glass member 10Q without edges.

[0065] The second vertical folding machine 260 can automatically control the timing of applying bending stress using a pressing roll.

[0066] <Separator> In the secondary transport path 202, the separator device 170 described in the first embodiment does not need to be installed.

[0067] <Inspection equipment> In the secondary transport path 202, the glass product sections 11A and 11B, which are transported by the transport roll 210, have their wedge angle measured at control position X detected by the inspection device 280 shown in Figure 3.

[0068] Figures 4B and 4C are plan views showing the wedge angle detection method at control position X. The inspection device 280 includes a plate thickness measuring device 281, as shown in Figure 4B. The plate thickness measuring device measures the plate thickness along the width direction L6 of the glass product sections 11A and 11B, including control position X. This creates a plate thickness profile as shown in Figure 4C, and the plate thickness at control position Y and control position Z is determined. As a result, the wedge angle at control position X of the glass product sections 11A and 11B is calculated. As the glass product sections 11A and 11B are transported in the width direction, the inspection device 280 can measure the plate thickness and calculate the wedge angle with a simpler mechanism than in the first embodiment.

[0069] <Control device> The wedge angle at control position X, calculated by the inspection device 280, is transmitted to the control device 290 shown in Figure 3. The control device 290 controls the wedge-shaped glass manufacturing apparatus 200 based on the transmitted wedge angle trend, thereby controlling the wedge angle at control position X so that the difference from the predetermined ideal wedge angle at control position X is within a predetermined range.

[0070] Similar to the first embodiment, the control device 290 moves the widthwise positions of the vertical cutting lines L1 to L4 by changing the widthwise position of each cutter 221 of the vertical cutting machine 220 based on the trend of the wedge angle. This makes it possible to cut out the glass product parts 11A and 11B from appropriate positions on the glass sheet 10 so that the wedge angle at the control position X approaches the ideal wedge angle.

[0071] Preferably, the control device 290 changes the widthwise position in which the first vertical folding machine 250 and the second vertical folding machine 260 apply bending stress based on the transmitted wedge angle trend and the change in the position of the vertical cutting line. The widthwise position in which the bending stress applied by the first vertical folding machine 250 can be moved by changing the widthwise position of the pressing projection and support rolls provided on the first vertical folding machine 250. The widthwise position in which the bending stress applied by the second vertical folding machine 260 can be moved by changing the timing in which the pressing rolls provided on the second vertical folding machine 260 apply bending stress. This makes it possible to cut out the glass product parts 11A and 11B from appropriate positions on the glass sheet 10 with higher precision.

[0072] [Wedge-shaped glass] Preferably, the difference between the maximum and minimum thickness of the wedge-shaped glass manufactured by the manufacturing method according to one embodiment of the present invention is 0.1 mm or more. If it is 0.1 mm or more, even when it is installed in a car as a windshield with a large angle to the horizontal, the occurrence of double images can be suppressed when it is used as information display glass. The difference between the maximum and minimum thickness of the wedge-shaped glass may be 0.3 mm or more, or 0.5 mm or more. On the other hand, the difference between the maximum and minimum thickness of the wedge-shaped glass may be 1.5 mm or less, 1.2 mm or less, or 1.0 mm or less. When using wedge-shaped glass as a windshield for a car, the optimal difference between the maximum and minimum thickness of the wedge-shaped glass is selected depending on the mounting angle of the windshield and the mounting angle and position of the illuminator that displays information on the windshield.

[0073] The main surface of the wedge-shaped glass manufactured by the manufacturing method according to one embodiment of the present invention preferably has a maximum height Rz of 0.3 μm or less of the roughness curve at a standard length of 25 mm as specified in JIS B0601:2001. If Rz is 0.3 μm or less, when the plate glass is used as information display glass, the scenery viewed through the glass will not be distorted, and the reflected image when information is displayed on the plate glass will not be distorted. Here, the roughness curve is represented by a shape waveform. Rz is more preferably 0.25 μm or less, and even more preferably 0.2 μm or less.

[0074] The wedge-shaped glass produced by the manufacturing method according to one embodiment of the present invention is not limited to automobile windshields, but may also be used for automobile or train windows, or motorcycle windshields, or any other type of glass that can display information. Furthermore, it is not limited to glass for displaying information in vehicles, but can be used for various other types of information display glass. In addition, it can be used in various devices that utilize continuous changes in transmission properties, even for applications other than information display. [Examples]

[0075] Examples of the present invention will be described below. In a glass manufacturing apparatus equipped with a main transport path and a secondary transport path connected perpendicularly to the main transport path, wedge-shaped glass was manufactured from a glass sheet with a convex cross-section. The main transport path was equipped with a vertical cutter, a horizontal cutter, a horizontal bender, and a first vertical bender, while the secondary transport path was equipped with a second vertical bender and an inspection device. The inspection device calculated the wedge angle at control position X of the glass product section from the thickness at control position Y, the thickness at control position Z, and the distance in the width direction between control position Y and control position Z. The glass manufacturing apparatus was also equipped with a control device, which controlled the width direction position of each cutter in the vertical cutter, the width direction position of the pressing projection and support roll in the first vertical bender, and the timing at which the pressing roll in the second vertical bender applied bending stress, based on the wedge angle at control position X of the glass product section detected by the inspection device.

[0076] The pitch distance of the conveying rolls of the glass manufacturing apparatus was 150 mm, and the conveying speed was 1800 m / h. As shown in Fig. 4C, the control positions Y, X, and Z were arranged in order in the width direction from the side with a smaller plate thickness to the side with a larger plate thickness of the glass product section, and the control position X was located at the midpoint between the control position Y and the control position Z. Further, the control position X was at a position 17 inches (431.8 mm) away in the width direction from the end (L1 or L2) on the side with a smaller plate thickness of the glass product section, and the ideal wedge angle δ i at the predetermined control position X was 0.36 mrad.

[0077] In Examples 1 to 7, the distance d in the width direction between the control positions Y and Z was changed, and the wedge angle δ at the control position X of the glass product section during conveyance was detected. Then, it was compared with the actual wedge angle δ r at the control position X of the glass product section detected in the stopped state. For each condition of Examples 1 to 7, verification was performed on 20 glass product sections, and if the absolute value of the difference δ - δ r was more than 0.1 mrad for one or more glass product sections, an "×" was entered in Table 1. If the absolute value of the difference δ - δ r was 0.1 mrad or less for all 20 glass product sections, an "○" was entered in Table 1. "○" means that the wedge angle at the control position X of the glass product section during conveyance can be measured with high precision, and "×" means the opposite.

[0078]

Table 1

[0079] In Examples 1 and 7, the distance d was less than 50 mm or more than 250 mm, and for one or more glass product sections, the absolute value of δ - δ r was more than 0.1 mrad. On the other hand, in Examples 2 to 6, the distance d satisfied 100 mm or more and 250 mm or less, and for all 20 glass product sections, the absolute value of δ - δ r was 0.1 mrad or less.

[0080] ​​​​If the distance d in the width direction between control position Y and control position Z is 50 mm or more and 200 mm or less, the wedge angle δ at control position X of the glass product detected during transport is equal to the actual wedge angle δ at control position X of the glass product detected when stopped. r It was found that the difference was small and could be detected with high accuracy. As a result, based on the high-precision wedge angle trend transmitted from the inspection device, the control device can control the glass manufacturing equipment with high precision, such as the position of the vertical cut line formed by the vertical cut machine and the position of the bending stress applied by the vertical folding machine.

[0081] Next, Example 8 involved the continuous production of 100 glass product sections under the conditions of Example 4 in Table 1, where the inspection device measured the wedge angle δ, and the control device controlled the vertical cutting machine, the first vertical folding machine, and the second vertical folding machine based on the trend of the wedge angle δ.

[0082] On the other hand, Example 9 was obtained when 100 glass product sections were continuously manufactured without the control device controlling the vertical cutting machine, the first vertical folding machine, and the second vertical folding machine, and the inspection device measured the wedge angle δ under the conditions of Example 4 in Table 1.

[0083] In Example 8, the wedge angle δ at the controlled position X of the manufactured glass product part and the ideal wedge angle δ at a predetermined controlled position X are shown. i (0.36 mrad) difference δ-δ i The absolute value of was 0.1 mrad or less for all 100 glass product sections, and the wedge angle δ was kept within the predetermined range.

[0084] On the other hand, in Example 9, for 3 out of 100 glass product sections, the wedge angle δ at the control position X of the manufactured glass product section and the ideal wedge angle δ at a predetermined control position X are compared. i (0.36 mrad) difference δ-δ i The absolute value of exceeded 0.1 mrad, making it impossible to keep the wedge angle δ within the specified range.

[0085] Based on the above, the control device controls the vertical cutting machine, the first vertical folding machine, and the second vertical folding machine based on the trend of the wedge angle δ detected by the inspection device, thereby determining that the wedge angle δ at the control position X of the manufactured glass product is equal to the ideal wedge angle δ at the predetermined control position X. i It was confirmed that the difference between the two values ​​could be maintained within a predetermined range.

[0086] This application is based on the Japanese Patent Application No. 2021-182124 filed on November 8, 2021, the contents of which are incorporated by reference within this application. [Industrial applicability]

[0087] According to the present invention, the wedge angle of wedge-shaped glass cut from a glass sheet can be brought closer to a predetermined target value, making it possible to obtain wedge-shaped glass that can be used for various applications. [Explanation of Symbols]

[0088] 10...Convex glass sheet, 11A...Glass product portion of glass sheet 10, 11B...Glass product portion of glass sheet 10, 12A...Ear portion of glass sheet 10, 12B...Ear portion of glass sheet 10, 13...Central portion of glass sheet 10, 20...Concave glass sheet, 21A...Glass product portion of glass sheet 20, 21B...Glass product portion of glass sheet 20, 22A...Ear portion of glass sheet 20, 22B...Ear portion of glass sheet 20, 23...Central portion of glass sheet 20, 30...Tapered Glass base plate, 31...Glass product part of glass base plate 30, 32A...Ear part of glass base plate 30, 32B...Ear part of glass base plate 30, 100...Wedge-shaped glass manufacturing apparatus, 110...Conveyor roll, 111...Conveyor roll shorter in the width direction than conveyor roll 110, 120...Longitudinal cutter, 121...Cutter of longitudinal cutter 120, 130...Cross-cutter, 131...Cutter of cross-cutter 130, 140...Cross-folding machine, 150...First longitudinal folding machine, 160...Second longitudinal folding machine, 170...Separation device, 180 ...Inspection device, 181...Thickness measuring device, 182...Sensor, 190...Control device, 200...Wedge-shaped glass manufacturing device, 201...Main conveyor path, 202...Sub-conveyor path, 210...Conveyor roll, 211...Conveyor roll shorter in the width direction than conveyor roll 210, 220...Longitudinal cutter, 221...Cutter for longitudinal cutter 220, 230...Cross-cutter, 231...Cutter for cross-cutter 230, 240...Cross-folding machine, 250...First longitudinal folding machine, 260...Second longitudinal folding machine, 280...Inspection device, 281...Thickness measuring device Apparatus, 290...Control device, L1...Longitudinal cut line formed at the boundary between glass product section 11A and ear section 12A, L2...Longitudinal cut line formed at the boundary between glass product section 11B and ear section 12B, L3...Longitudinal cut line formed at the boundary between glass product section 11A and central section 13, L4...Longitudinal cut line formed at the boundary between glass product section 11B and central section 13, L5...Transverse cut line, L6...Width-direction line used by the inspection device to measure plate thickness, E1...One end of glass product section 11A, E2...One end of glass product section 11B

Claims

1. A glass sheet having a thickness variation along its width is transported by multiple transport rolls, A vertical cutting machine is used to form vertical cuts in the longitudinal direction of the glass sheet. A crosscutting machine is used to form crosscut lines in the width direction of the glass sheet. By applying bending stress to the glass sheet using a transverse bending machine, the glass sheet is cut along the transverse cutting line to form a glass member. By applying bending stress to the glass member using a vertical folding machine, the glass member is cut along the vertical cutting line, the unnecessary portion is separated, and a wedge-shaped glass product portion is formed. The inspection device detects the wedge angle at the control position X of the glass product part, Based on the wedge angle at the control position X, the position in the width direction of the vertical cut line formed by the vertical cutter is controlled. A method for manufacturing wedge-shaped glass, characterized by controlling the wedge angle at the control position X such that the difference between it and a predetermined ideal wedge angle at the control position X falls within a predetermined range.

2. A method for manufacturing wedge-shaped glass according to claim 1, wherein the position in the width direction of the bending stress applied by the vertical folding machine is controlled based on the wedge angle at the control position X.

3. A separator is positioned between the conveying rolls to separate the glass product portion and the unwanted portion in the width direction. A method for manufacturing wedge-shaped glass according to claim 1 or 2, wherein the position of the separator is changed based on the wedge angle at the control position X.

4. The method for manufacturing wedge-shaped glass according to claim 1 or 2, wherein the wedge angle at the control position X detected while transporting the glass product is within plus or minus 0.1 mrad of the actual wedge angle at the control position X detected when the movement of the glass product is stopped.

5. The wedge angle at the control position X, detected while transporting the glass product, is calculated from the thickness at control position Y, which is moved in the width direction from control position X, the thickness at control position Z, which is moved in the width direction opposite to control position Y from control position X, and the distance in the width direction between control position Y and control position Z. The method for manufacturing wedge-shaped glass according to claim 1 or 2, wherein the distance in the width direction between the control position Y and the control position Z is 50 mm or more and 250 mm or less.

6. The method for manufacturing wedge-shaped glass according to claim 1 or 2, wherein the management position X is located within the display area of ​​the head-up display.

7. The method for manufacturing wedge-shaped glass according to claim 6, wherein the wedge angle within the head-up display area is maintained at 0.20 mrad or more and 1.50 mrad or less.

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