TW202304609A - Glass plate manufacturing method and transfer mold - Google Patents

Abstract

A method for manufacturing a glass plate including a curved surface shape, the method including the following (A)-(E). (A) A first transfer mold provided with a first pin group including three or more first pins that are parallel to each other and are independently movable in the longitudinal direction is prepared. (B) the tail ends of the first pins abut against the curved surface of the first master mold, and the positions of the first pins are adjusted and fixed. (C) The first pins are separated from the first master mold in a state where the positions of the first pins are fixed. And (D) placing the glass plate on the first transfer mold with the ends of the fixed first pins facing upward. And (E) heating the glass plate, and bending and forming the glass plate along the tail ends of the fixed first pins.

Description

Manufacturing method of glass plate, and transfer mold

The invention relates to a manufacturing method of a glass plate and a transfer printing mold.

The bending apparatus described in Patent Document 1 includes a heater, a first pin group, a first guide plate, a first movable plate, and a first moving mechanism. The heater heats the forming plate. The first pin group includes three or more first pins that are in contact with the first main surface of the formed plate. The first guide plate supports three or more first pins so that they are parallel to each other, and supports three or more first pins so that they can move independently and freely along their respective length directions . The first movable plate is arranged on the opposite side to the forming plate with reference to the first guide plate. A first molding die having a first curved surface in contact with the first pin group is attached to the first movable plate. The first moving mechanism moves the first movable plate relative to the first guide plate in the longitudinal direction of the first pin. [Prior Art Literature] [Patent Document]

[Patent Document 1] International Publication No. 2020/080305

[Problem to be solved by the invention]

In Patent Document 1, the position of each first pin is adjusted to a desired position by pushing up the lower end of each first pin by the upwardly facing curved surface of the first forming die. In this state, a glass plate is placed on the first pin group, and the glass plate is bent along the upper end of each first pin.

For example, when placing a plurality of glass plates on different pin groups and bending each glass plate, it is necessary to prepare a master mold for adjusting the positions of the pins constituting the pin group for each pin group. . Therefore, the number of master molds will increase.

One aspect of the present invention provides a technique that reduces the number of master dies used to adjust the position of each pin constituting a pin group. [Technical means to solve the problem]

The manufacturing method of the glass plate of 1 aspect of this invention is the manufacturing method of the glass plate containing a curved surface shape, and includes following (A)-(E). (A) A first transfer mold having a first pin group including three or more first pins that are independently movable in the longitudinal direction and parallel to each other is prepared. (B) Make the head end of each of the above-mentioned first pins touch the curved surface of the first original mold, adjust and fix the position of each of the above-mentioned first pins. (C) In a state where the position of each of the above-mentioned first pins is fixed, each of the above-mentioned first pins is separated from the above-mentioned first master mold. (D) Make the above-mentioned head end of each of the above-mentioned fixed first pins face up, and place a glass plate on the above-mentioned first transfer mold. (E) heating the above-mentioned glass plate to bend the above-mentioned glass plate along the above-mentioned head end of each of the above-mentioned fixed first pins.

A transfer mold according to an aspect of the present invention is used for manufacturing a glass plate including a curved shape. The transfer mold includes: a pin group, which includes three or more pins that are independently movable along the length direction and are parallel to each other; and a fixing member, which maintains the position of each of the above-mentioned pins and makes them movable. [Effect of Invention]

According to an aspect of the present invention, the positions of the pins constituting the pin group are fixed. Each pin can be separated from the original mold under the condition that the position of each pin is fixed, so that the original mold can be reused. Therefore, the number of master molds can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, the same code|symbol may be attached|subjected to the same or corresponding structure, and description may be abbreviate|omitted. In addition, in each drawing, the X-axis direction, the Y-axis direction, and the Z-axis direction are directions perpendicular to each other, and the X-axis direction and the Y-axis direction are horizontal directions, and the Z-axis direction is a vertical direction. The positive direction of the Z axis is the vertical upward direction, and the negative direction of the Z axis is the vertical downward direction.

Referring to FIG. 1, the manufacturing method of the glass plate which concerns on one Embodiment is demonstrated. As shown in FIG. 1 , the manufacturing method of a glass plate includes steps S101-S105. Step S101 includes preparing the first transfer mold 1 . For example, as shown in FIGS. 2 to 4 , the first transfer mold 1 includes a first pin group 2 and a first fixture 3 .

The first pin group 2 includes three or more first pins 21 that are independently movable in the longitudinal direction and that are parallel to each other. The first fixing member 3 maintains the positions of the first pins 21 so as to be movable. The positions of the first pins 21 can be adjusted, so that various curved glass plates 9 can be formed (see FIG. 6 ). Also, the deviation between the curved shape of the glass plate 9 and the target curved shape can be measured, and the positions of the first pins 21 can be finely adjusted so that the deviation can be reduced.

The thickness of the glass plate 9 is preferably at least 0.2 mm, more preferably at least 0.8 mm, and still more preferably at least 1 mm. The thickness of the glass plate 9 is preferably not more than 5 mm, more preferably not more than 3 mm, and still more preferably not more than 2 mm. The radius of curvature of the glass plate 9 is preferably at least 50 mm, more preferably at least 100 mm, and still more preferably at least 200 mm. The radius of curvature of the glass plate 9 is, for example, 10000 mm or less.

The size of the glass plate 9 can be appropriately selected according to the application. For example, when used as a cover glass for a vehicle-mounted display device, the length of the short side is, for example, not less than 50 mm and not more than 500 mm, preferably not less than 100 mm and not more than 300 mm, and the length of the long side is, for example, not less than 50 mm and not more than 1500 mm , preferably not less than 100 mm and not more than 1200 mm.

The glass constituting the glass plate 9 is not particularly limited, and alkali-free glass, soda-lime glass, soda-lime silicate glass, aluminosilicate glass, borosilicate glass, lithium aluminosilicate glass, borosilicate glass, etc. can be used. Silicate glass. In particular, when the glass plate 9 is used for a cover glass of a display device, glass containing an alkali metal oxide as shown below is preferable. Glass containing alkali metal oxides can form a compressive stress layer on the glass surface by performing chemical strengthening treatment after forming, thereby increasing the strength. Specific examples of the composition of the glass are not particularly limited, but include 50% to 80% of SiO ₂ , 0.1% to 25% of Al ₂ O ₃ , 3% to Glass with 30% _Li2O + _Na2O + _K2O , 0%~25% MgO, 0%~25% CaO and 0%~5% _ZrO2 . More specifically, the glass composition of following (i)-(v) is mentioned. Furthermore, for example, "comprising 0% to 25% of MgO" means that MgO is not required, but may be contained up to 25%. The glass of the following (i) is included in the soda lime silicate glass, and the glasses of the following (ii), (iii), and (iv) are included in the aluminosilicate glass. The glass of (v) below is included in the lithium aluminosilicate glass. (i) The composition expressed in mole % based on oxides includes 63% to 73% of SiO ₂ , 0.1% to 5.2% of Al ₂ O ₃ , 10% to 16% of Na ₂ O, 0% to 1.5% Glass of K ₂ O, 0%-5% Li ₂ O, 5%-13% MgO and 4%-10% CaO. (ii) The composition represented by mole % based on oxides contains 50% to 74% of SiO ₂ , 1% to 10% of Al ₂ O ₃ , 6% to 14% of Na ₂ O, 3% to 11% K ₂ O, 0%~5% Li ₂ O, 2%~15% MgO, 0%~6% CaO and 0%~5% ZrO ₂ , and the content of SiO ₂ and Al ₂ O ₃ The total content of Na ₂ O and K ₂ O is 12% to 25%, and the total content of MgO and CaO is 7% to 15%. (iii) The composition represented by mole % based on oxide contains 68% to 80% of SiO ₂ , 4% to 10% of Al ₂ O ₃ , 5% to 15% of Na ₂ O, 0% to 1% Glass of K ₂ O, 0%-5% Li ₂ O, 4%-15% MgO and 0%-1% ZrO ₂ . (iv) The composition represented by mole % based on oxides contains 67% to 75% of SiO ₂ , 0% to 4% of Al ₂ O ₃ , 7% to 15% of Na ₂ O, 1% to 9% K ₂ O, 0%~5% Li ₂ O, 6%~14% MgO, 0%~1.5% ZrO ₂ , and the total content of SiO ₂ and Al ₂ O ₃ is 71%~75% , the total content of Na ₂ O and K ₂ O is 12% to 20%, and in the case of containing CaO, the content is less than 1%. (v) The composition expressed in mole% based on oxides contains 56% to 73% of SiO ₂ , 10% to 24% of Al ₂ O ₃ , 0% to 6% of B ₂ O ₃ , 0% to 6% % of P ₂ O ₅ , 2% to 7% of Li ₂ O, 3% to 11% of Na ₂ O, 0% to 2% of K ₂ O, 0% to 8% of MgO, 0% to 2% CaO, 0%-5% SrO, 0%-5% BaO, 0%-5% ZnO, 0%-2% TiO ₂ , 0%-4% ZrO ₂ glass.

The respective first pins 21 are arranged in parallel in the Z-axis direction, for example. The longitudinal direction of each first pin 21 is, for example, the Z-axis direction. When viewed from the longitudinal direction of each first pin 21, the plurality of first pins 21 may be arranged in a dislocation as shown in FIG. 3, or may be arranged in a matrix.

When viewed from the longitudinal direction of each first pin 21, the head end of each first pin 21 (such as the first head 26) is circular, but it can also be polygonal (such as triangle, quadrangle, or hexagon). In the latter case, the head ends of the adjacent first pins 21 can be stably pressed against each other. On the other hand, in the former case, gaps can be formed between adjacent first pins 21, thereby reducing the heat capacity of the first pin group 2, and raising the temperature of the first pin group 2 in a short time.

As shown in FIG. 4 , the head end of each first pin 21 includes a dome-shaped curved surface 22 protruding upward, and the glass plate 9 is supported from below by the curved surface 22 . Compared with the case where the glass plate 9 is supported by the curved surface 22 of the first pin 21 and the corner 24 of the side surface 23, local stress concentration on the glass plate 9 can be suppressed. The curved surface 22 is, for example, hemispherical, and its radius of curvature is determined in consideration of the radius of curvature of the glass plate 9 and the like. Furthermore, the dome-shaped curved surface 22 may be a toric surface convex upward, or may be aspherical.

The first fixing member 3 holds the positions of the first pins 21 in the Z-axis direction so as to be movable. Each first pin 21 is in a state held so as not to fall off, and the position of each first pin 21 in the Z-axis direction can be adjusted. The first stator 3 includes, for example, a first outer frame 31 and a first movable wedge 32 . The first outer frame 31 surrounds the first pin group 2 . The first movable wedge 32 protrudes toward the inner side of the first outer frame 31 as shown in FIG. 5 , so that adjacent first pins 21 are pressed against each other.

The first outer frame 31 is, for example, a square frame. The first movable wedge 32 protrudes from one of the two opposing side walls of the first outer frame 31 toward the other side wall, so that the adjacent first pins 21 are pressed against each other. The first outer frame 31 can also be a round frame or an oval frame not shown, and the shape of the frame is not particularly limited.

The first movable wedge 32 is movable in the X-axis direction, for example. The operator or the working robot moves the first movable wedge 32 in the positive direction of the X-axis, so that the first pins 21 are gathered in the positive direction of the X-axis, and the adjacent first pins 21 are pressed against each other. As a result, the position in the Z-axis direction of each first pin 21 can be fixed.

In addition, the worker or the robot moves the first movable wedge 32 in the negative direction of the X axis, thereby releasing the positional fixation of the first pins 21 in the Z axis direction. The position in the Z-axis direction of each first pin 21 can be adjusted, so that glass plates 9 of various curved shapes can be formed.

The first fixing member 3 may further include a first screw 33 that presses the first pin 21 through the first movable wedge 32 . In this case, the first outer frame 31 includes a first screw hole 34 into which the first screw 33 is screwed. The first screw 33 is, for example, a headless full thread screw.

A worker or a working robot can move the first movable wedge 32 by rotating the first screw 33, so that the adjacent first pins 21 can be pressed against each other. If the rotation of the first screw 33 is stopped in this state, the first screw 33 will continue to push the first movable wedge 32 . Therefore, it is possible to prevent the first movable wedge 32 from being pushed back by the reaction force.

Furthermore, although not shown, the first fixture 3 may further include a first cylinder instead of the first screw 33 . The first cylinder has: a cylinder, a piston that moves inside the cylinder, and a rod that moves together with the piston. The first cylinder presses the first pin 21 via the first movable wedge 32 by air pressure or hydraulic pressure.

The first fixing member 3 may include a first alignment plate 36, and the first alignment plate 36 is formed with a plurality of first alignment holes 35 through which the first pins 21 are inserted one by one. The first alignment plate 36 is fixed to the first outer frame 31 by, for example, bolts (not shown) or the like. The plurality of first arrangement holes 35 are arranged in a dislocation like the plurality of first pins 21 , and may also be arranged in a matrix. The horizontal position of the first pins 21 can be regulated by the horizontal position (the X-axis position and the Y-axis position) of the first alignment holes 35, so that the first pins 21 can be arranged in a desired manner.

The first pin 21 may include: a first intermediate shaft 25 inserted through the first alignment hole 35; a first head 26 detachably mounted on one end of the first intermediate shaft 25 in the longitudinal direction; and a first protrusion The edge 27 is disposed at the other end of the first intermediate shaft 25 in the longitudinal direction. The 1st pin 21 is provided so that the 1st head part 26 may face the glass plate 9. As shown in FIG.

The first head portion 26 includes a dome-shaped curved surface 22 protruding upward, and the glass plate 9 is supported from below by the curved surface 22 . Adjacent first heads 26 are pressed against each other by their side surfaces 23 . Since the first head portion 26 is detachable, it can be replaced even if it is damaged.

For example, the first head portion 26 includes a screw hole 28 on a surface opposite to the curved surface 22 . The first intermediate shaft 25 includes a screw screwed into the screw hole 28 . Thereby, the first head portion 26 is detachably attached to the first intermediate shaft 25 .

The first head portion 26 and the first flange 27 prevent the first intermediate shaft 25 from falling out of the first alignment hole 35 . The respective diameters of the first head portion 26 and the first flange 27 are larger than the diameter of the first arrangement hole 35 .

The first head 26 may further include a hollow hole 29 connected to the screw hole 28 . That is, the first head portion 26 may have a hollow structure. The heat capacity of the first head portion 26 can be reduced, thereby shortening the heating time of the first head portion 26 .

However, the details will be described later, and the first transfer mold 1 is heated from the outside together with the glass plate 9 . When the temperature rise rate is faster, the temperature of the first outer frame 31 and the first movable wedge 32 may be higher than the temperature of the first pin 21 inside it during the temperature rise.

Therefore, the first outer frame 31 and the first movable wedge 32 can be formed of a material having an average linear expansion coefficient lower than that of the first pin 21 . Thereby, in the middle of temperature rise, the first outer frame 31 and the like are wider than the first pin group 2 , and the relaxation of the force of the adjacent first pins 21 pressing against each other can be restricted. The average linear expansion coefficient is the average value of the linear expansion coefficients from room temperature (for example, 20° C.) to the forming temperature of the glass plate 9 .

However, when the temperature rise rate is relatively slow, the first outer frame 31 and the first movable wedge 32 have the same temperature as the first pin group 2 inside. Therefore, the first outer frame 31 and the first movable wedge 32 may also be formed of the same material as the first pin 21 .

The first pin 21, the first outer frame 31, or the first movable wedge 32 are made of metal (such as stainless steel, heat-resistant steel, or cemented carbide), ceramics (such as silicon carbide, silicon nitride, or quartz), or carbon.

The stainless steel can be any one of Matian iron series and Worth field iron series. The average linear expansion coefficient of Matian loose iron system is smaller than the average linear expansion coefficient of Wasitian iron system. The cemented carbide is, for example, tungsten carbide.

The first pin 21, the first outer frame 31, or the first movable wedge 32 may include a base material and a coating film formed on the base material, and may be formed of a plurality of materials. It is sufficient that the coating film covers at least a part of the base material. The coating film is metal film, ceramic film or carbon film, etc.

Step S102 includes: as shown in FIG. 5 , make the head end of each first pin 21 touch the curved surface 41 of the first master mold 4 , adjust and fix the Z-axis position of each first pin 21 . The position in the Z-axis direction of each first pin 21 is fixed by the first fixing member 3 in this embodiment, but it may also be fixed by welding or the like.

If the position in the Z-axis direction of each first pin 21 is fixed by the first fixing member 3 or welding, etc., before the glass plate 9 is placed on the first transfer mold 1, the first transfer mold 1 can be placed Separated from the first master mold 4, the separated first master mold 4 can be reused. Therefore, for example, when placing a plurality of glass plates 9 on different first transfer molds 1 to bend each glass plate 9 , the number of first master molds 4 can be reduced.

Unlike the first transfer mold 1 , the first master mold 4 is not heated. Therefore, the first master mold 4 can be formed of a material lower in heat resistance than the first transfer mold 1, and can be manufactured at low cost and in a short time. The first master mold 4 is manufactured by, for example, a 3D (three-dimensional, three-dimensional) printer, for example, resin is used as its material. Furthermore, the first master mold 4 can also be manufactured by cutting or injection molding. Also, the material of the first master mold 4 is not limited to resin, and may be carbon or metal (such as stainless steel or aluminum).

The curved surface 41 of the first master mold 4 may be a single curved surface or a double curved surface. A single curved surface is a cylindrical surface, etc., which has a fixed cross-sectional shape in a specified direction. On the other hand, the toric surface has a curved cross-sectional shape in both the cross-section perpendicular to the X-axis direction and the cross-section perpendicular to the Y-axis direction.

Step S103 includes: separating each first pin 21 from the first master mold 4 in a state where the position in the Z-axis direction of each first pin 21 is fixed. The separated first master mold 4 can be reused. Therefore, for example, when placing a plurality of glass plates 9 on different first transfer molds 1 to bend each glass plate 9 , the number of first master molds 4 can be reduced.

Step S104 includes: as shown in FIG. 6 , place the glass plate 9 on the first transfer mold 1 with the head end (for example, the first head 26 ) of each first pin 21 fixed in step S102 facing upward. The first transfer mold 1 is a lower mold that supports the glass plate 9 from below.

Step S104 may also include: laying a heat-resistant cloth 5 between the first transfer mold 1 and the glass plate 9 . The heat-resistant fabric 5 is, for example, a non-woven fabric containing stainless steel fibers or silica fibers. By laying the heat-resistant cloth 5, the traces of the first pins 21 can be suppressed from adhering to the glass plate 9.

The heat-resistant fabric 5 has a thickness of 0.3 mm to 1.5 mm, a surface density of 100 g/m ² to 1400 g/m ² , and an air permeability of 20 cc/(cm ² ·sec) to 200 cc/(cm ² ·sec). Air permeability is measured according to Japanese Industrial Standard JIS R3240:2013.

If the heat-resistant cloth 5 has the above-mentioned physical properties, the heat transfer between the first pin 21 and the glass plate 9 can be suppressed, the thermal stress of the glass plate 9 can be relaxed, and the heat-resistant cloth can be suppressed when the glass plate 9 is bent into a complex shape. 5 produces wrinkles.

The thickness of the heat-resistant cloth 5 is preferably from 0.3 mm to 1.0 mm, more preferably from 0.5 mm to 1.0 mm. The surface density of the heat-resistant cloth 5 is preferably 500 g/m ² -1000 g/m ² . The air permeability of the heat-resistant cloth 5 is preferably 20 cc/(cm ² ·sec)-160 cc/(cm ² ·sec).

Step S105 includes: as shown in FIG. 7 , heating the glass plate 9 to bend the glass plate 9 along the head ends of the first pins 21 fixed in step S102 . The distance P (not shown) between the centerlines of the adjacent first pins 21 fixed in step S102 is 5 mm˜30 mm. The pitch P is equal to the diameter of the first pin 21 in this embodiment, but may be larger than the diameter of the first pin 21 as described below.

If the pitch P is 5 mm or more, the thickness of the first pin 21 is thick enough to suppress deformation of the first pin 21 . On the other hand, if the pitch P is 30 mm or less, the glass plate 9 can be suppressed from hanging down partially between the adjacent first pins 21 . The pitch P is preferably 5 mm to 20 mm.

Step S105 includes: in the state where the glass plate 9 is placed on the first transfer mold 1 , put the first transfer mold 1 into the heating furnace, and heat the glass plate 9 . The heating furnace can be batch type or continuous type. The heating furnace may be provided with a conveyor belt for conveying the first transfer mold 1, and may be of a continuous conveying type. The continuous conveying furnace is divided into several zones along the conveying path. The glass plate 9 is conveyed together with the first transfer mold 1 and heated.

Step S105 may also include: heating the glass plate 9 at a preset forming temperature. The forming temperature is set, for example, within a temperature range in which the viscosity of the glass ranges from 10 ⁸ Pa·s to 10 ¹² Pa·s. When the viscosity of the glass is 10 ⁸ Pa·s or more, the traces of the first pins 21 can be suppressed from adhering to the glass plate 9 . On the other hand, if the viscosity of the glass is 10 ¹² Pa·s or less, the glass plate 9 can be bent and formed. The viscosity of the glass is preferably 10 ^8.5 dPa·s to 10 ^11.5 dPa·s.

Step S105 includes: for example, bending the glass plate 9 into shape by the weight of the glass plate 9 . Unlike the case where the upper surface of the glass plate 9 is pressed by a pressing machine or the like, it is possible to prevent contact traces of the pressing machine from adhering to the glass plate 9 .

Step S105 may also include: bending the glass plate 9 into shape by the self-weight and air pressure of the glass plate 9 . For example, blowing compressed air to the periphery of the glass plate 9 can reliably bend the periphery of the glass plate 9 .

In this embodiment, step S105 does not use a press, but a press may also be used. The press is installed, for example, in one area of a continuous transfer heating furnace. The pressing machine presses the upper mold arranged above the glass plate 9 downward, and the glass plate 9 is clamped by the upper mold and the first transfer mold 1 to form it under pressure. The upper mold is attached to the press machine, but it may be placed on the glass plate 9 and conveyed together with the glass plate 9 . In the latter case, the upper mold may be the second transfer mold 6 described below.

Next, the method of manufacturing the second transfer mold 6 and the glass plate using the second transfer mold 6 will be described with reference to FIGS. 8 to 11 . The second transfer mold 6 is used in combination with the first transfer mold 1 . In this case, step S101 includes: preparing the second transfer mold 6 . The second transfer mold 6 is configured in the same manner as the first transfer mold 1 , and includes, for example, a second pin group 7 and a second fixture 8 as shown in FIG. 8 .

The second pin group 7 includes three or more second pins 71 that are independently movable in the longitudinal direction and that are parallel to each other. The second fixing member 8 maintains the positions of the second pins 71 so as to be movable. The positions of the second pins 71 can be adjusted so that glass plates 9 of various curved shapes can be formed. In addition, the deviation between the curved surface shape of the glass plate 9 and the target curved surface shape can be measured, and the position of each second pin 71 can be finely adjusted so that the deviation can be reduced.

The respective second pins 71 are arranged in parallel in the Z-axis direction, for example. The longitudinal direction of each second pin 71 is, for example, the Z-axis direction. When viewed from the longitudinal direction of each second pin 71, the plurality of second pins 71 are arranged in a dislocation manner, or may be arranged in a matrix.

As shown in FIG. 8 , the head end of each second pin 71 includes a downwardly convex dome-shaped curved surface 72 , and the glass plate 9 is pushed from above by the curved surface 72 . Compared with the case where the glass plate 9 is pressed by the curved surface 72 and the corner 74 of the side surface 73 of the second pin 71, local stress concentration on the glass plate 9 can be suppressed.

The second fixing member 8 holds the position in the Z-axis direction of each second pin 71 so as to be movable. The second stator 8 includes, for example, a second outer frame 81 and a second movable wedge 82 . The second outer frame 81 includes the second pin group 7 . The second movable wedge 82 protrudes toward the inner side of the second outer frame 81 as shown in FIG. 9 , so that the adjacent second pins 71 are pressed against each other.

The second fixing member 8 may further include a second screw 83 that presses the second pin 71 through the second movable wedge 82 . In this case, the second outer frame 81 includes a second screw hole 84 into which the second screw 83 is screwed. The second screw 83 is, for example, a headless full thread screw.

In addition, although not shown, the second fixture 8 may further include a second cylinder instead of the second screw 83 . The second cylinder has a cylinder, a piston that moves inside the cylinder, and a rod that moves with the piston. The second cylinder presses the second pin 71 via the second movable wedge 82 by air or hydraulic pressure.

The second fixing member 8 may include a second alignment plate 86, and the second alignment plate 86 is formed with a plurality of second alignment holes 85 through which the second pins 71 are inserted one by one. The second array plate 86 is fixed to the second outer frame 81 by, for example, bolts (not shown) or the like. The plurality of second array holes 85 are arranged in the same manner as the plurality of second pins 71 .

The second pin 71 may include: a second intermediate shaft 75 inserted through the second alignment hole 85; a second head 76 removably mounted on one end of the second intermediate shaft 75 in the longitudinal direction; and a second convex The edge 77 is provided at the other end of the second intermediate shaft 75 in the longitudinal direction. The 2nd pin 71 is provided so that the 2nd head part 76 may face the glass plate 9. As shown in FIG.

The second head portion 76 includes a downwardly convex dome-shaped curved surface 72, and the glass plate 9 is pressed from above by the curved surface 72. Adjacent second heads 76 are pressed against each other by their side faces 73 . Since the second head 76 is detachable, it can be replaced even if it is damaged.

For example, the second head portion 76 includes a screw hole 78 on a surface opposite to the curved surface 72 . The second intermediate shaft 75 includes a screw threaded into the screw hole 78 . Thereby, the second head portion 76 is detachably attached to the second intermediate shaft 75 .

The second head portion 76 and the second flange 77 prevent the second intermediate shaft 75 from falling out of the second alignment hole 85 . The respective diameters of the second head portion 76 and the second flange 77 are larger than the diameter of the second arrangement hole 85 .

The second head portion 76 may further include a hollow hole 79 connected to the screw hole 78 . That is, the second head portion 76 may have a hollow structure. The heat capacity of the second head portion 76 can be reduced, thereby shortening the heating time of the second head portion 76 .

The second outer frame 81 and the second movable wedge 82 may be formed of a material having an average linear expansion coefficient lower than that of the second pin 71 . However, the second outer frame 81, the second movable wedge 82, and the second pin 71 may also be formed of the same material.

The second pin 71, the second outer frame 81, or the second movable wedge 82 is made of metal (such as stainless steel, heat-resistant steel, or cemented carbide), ceramics (such as silicon carbide, silicon nitride, or quartz), or carbon.

The second pin 71, the second outer frame 81, or the second movable wedge 82 may include a base material and a coating film formed on the base material, and may be formed of a plurality of materials. It is sufficient that the coating film covers at least a part of the base material.

Step S102 includes: as shown in FIG. 9 , make the head end of each second pin 71 touch the curved surface 41A of the second master mold 4A, and adjust and fix the Z-axis position of each second pin 71 . The position in the Z-axis direction of each second pin 71 is fixed by the second fixing tool 8 in this embodiment, but it may be fixed by welding or the like.

If the position in the Z-axis direction of each second pin 71 is fixed by the second fixing member 8 or welding, etc., before the second transfer mold 6 is placed on the glass plate 9, the second transfer mold 6 can be placed Separated from the second master mold 4A, the separated second master mold 4A can be reused. Therefore, for example, when placing different second transfer molds 6 on a plurality of glass plates 9 to bend each glass plate 9 , the number of second master molds 4A can be reduced.

Unlike the second transfer mold 6, the second master mold 4A is not heated. Therefore, the second master mold 4A can be formed of a material lower in heat resistance than the second transfer mold 6, and can be manufactured at low cost and in a short time. The second master mold 4A is manufactured by, for example, a 3D printer, and resin is used as its material, for example. Furthermore, the second master mold 4A can also be manufactured by cutting, injection molding, or the like. Also, the material of the second master mold 4A is not limited to resin, and may be carbon or metal (such as stainless steel or aluminum).

The curved surface 41A of the second master mold 4A may be a single curved surface or a complex curved surface. The curved surface 41A of the second master mold 4A may have a different radius of curvature from the curved surface 41 of the first master mold 4 . More specifically, the curved surface 41A of the second master mold 4A may have a smaller radius of curvature than the curved surface 41 of the first master mold 4 .

Step S103 includes: separating each second pin 71 from the second master mold 4A in a state where the position in the Z-axis direction of each second pin 71 is fixed. The separated second master mold 4A can be reused. Therefore, for example, when placing different second transfer molds 6 on a plurality of glass plates 9 to bend each glass plate 9 , the number of second master molds 4A can be reduced.

Step S104 comprises: as shown in Figure 10, make the head end (such as the 2nd head 76) of each second pin 71 fixed in step S102 face down, the 2nd transfer mold 6 is placed on the glass plate 9 superior. The second transfer mold 6 is an upper mold that presses the glass plate 9 from above.

Step S104 may also include: laying a heat-resistant cloth 5A between the second transfer mold 6 and the glass plate 9 . The heat-resistant cloth 5A is constituted in the same manner as the heat-resistant cloth 5 . By laying the heat-resistant cloth 5A, the traces of the second pins 71 can be suppressed from adhering to the glass plate 9 . Furthermore, when the glass plate 9 is press-formed by the upper mold installed on the press machine, the heat-resistant cloth 5A may be laid on the glass plate 9 .

The second fixing member 8 may include a mounting plate 87 for mounting the heat-resistant cloth 5A on the second outer frame 81 . The heat-resistant cloth 5A can be unfolded along the head ends of the second pins 71 fixed in step S102.

The mounting plate 87 is fixed to the second outer frame 81, and the heat-resistant cloth 5A is mounted to the mounting plate 87 by a plurality of bolts 88 and the like. Each bolt 88 is inserted into the through hole of the heat-resistant cloth 5A, and is screwed into the bolt hole of the mounting plate 87 .

Furthermore, the first fixing member 3 does not include a mounting plate for mounting the heat-resistant cloth 5 on the first outer frame 31, but may also include the mounting plate. In the case of the latter, the glass plate 9 is pushed from above by the second transfer mold 6, and the heat-resistant cloth 5 laid under the glass plate 9 is bent along the head ends of the first pins 21 fixed in step S102. . Furthermore, before the second transfer mold 6 is placed on the glass plate 9, the heat-resistant cloth 5 laid under the glass plate 9 is spread flat by the mounting plate.

Step S104 may also include: by inserting the guide rod 11 fixed on the first transfer mold 1 into the guide hole 61 fixed on the second transfer mold 6, vertically relative to the first transfer mold 1 The direction guides the second transfer mold 6 . Tilting of the second transfer mold 6 and the like can be suppressed.

Three or more guide rods 11 are provided, and each is vertically erected. Each guide rod 11 is provided with a guide hole 61 . Furthermore, the arrangement of the guide rod 11 and the guide hole 61 can also be reversed. That is, the guide rod 11 may be fixed to the second transfer mold 6 and the guide hole 61 may be fixed to the first transfer mold 1 .

Step S105 includes: as shown in FIG. 11 , heating the glass plate 9 to bend the glass plate 9 along the head ends of the second pins 71 fixed in step S102. The glass plate 9 can be pressed by the weight of the second transfer mold 6, and the entire glass plate 9 can be reliably bent.

Next, referring to FIG. 12, a modification example of the first fixing member 3 will be described. The first fixing member 3 in the above embodiment uses the first outer frame 31 and the first movable wedge 32 to press adjacent first pins 21 against each other to fix the position of each first pin 21 in the Z-axis direction. On the other hand, the first fixing member 3 of this modification uses the first alignment plate 36 and the movable plate 37 to fix the positions of the first pins 21 in the Z-axis direction.

In the movable plate 37, similarly to the first alignment plate 36, a plurality of insertion holes 38 through which the first pins 21 are inserted one by one are formed. The plurality of insertion holes 38 are arranged in the same manner as the plurality of first pins 21 . If the movable plate 37 is moved in a direction perpendicular to the longitudinal direction of each first pin 21, each first pin 21 can be clamped by the first alignment plate 36 and the movable plate 37, and each first pin can be 21 is fixed in the Z-axis direction. Furthermore, the second fixing member 8 can also be configured in the same manner as the first fixing member 3 of this modification. [Example]

Next, the experimental data will be explained. In Examples 1 to 6, except for the conditions shown in Table 1, bending of the glass plate was implemented under the same conditions. The glass plate is soda lime glass. The X-axis dimension of the glass plate before bending is 300 mm, the Y-axis dimension is 200 mm, and the Z-axis dimension (thickness) is 1.8 mm. The target curved surface of the lower surface of the bent glass plate is a single curved surface. In this single curved surface, the radius of curvature of the cross-sectional shape perpendicular to the Y-axis direction is 900 mm, and the cross-sectional shape perpendicular to the X-axis direction is linear. Example 1 to Example 6 are all examples. Main conditions and results are shown in Table 1.

[Table 1] example 1 Example 2 Example 3 Example 4 Example 5 Example 6 condition Transfer mold die only die only upper and lower models upper and lower models upper and lower models upper and lower models Pin spacing [mm] 6 6 6 6 6 6 Radius of curvature of the pin head [mm] 3 3 3 3 3 -(flat) Curvature radius of target surface [mm] 900 900 900 900 900 900 With or without heat-resistant cloth have none have have have have Heating rate[℃/min] 2.583 2.583 2.583 2.500 2.417 2.417 Forming temperature [°C] 620 620 620 600 580 580 logη 10.7 10.7 10.7 11.4 12.3 12.3 Forming time [min] 20 20 20 1 1 1 result Ra[μm] 0.00253515 0.00654000 0.00588700 0.00199555 0.00142465 0.00237300 Evaluation of sales marks △ x △ 〇 〇 △ Wa[μm] 0.00022667 0.00120280 0.00106205 0.00034483 0.00034062 0.00075100 Evaluation of ups and downs 〇 x x △ △ △ PV value [mm] 0.510 0.037 0.155 0.158 0.168 0.151 Evaluation of shape error △ 〇 〇 〇 〇 〇 In Table 1, the transfer mold is only the lower mold, which means that the glass plate is bent and shaped only by the weight of the glass plate, and the transfer mold is an upper and lower mold, which means that the weight of the upper mold and the weight of the glass plate make the The glass sheet is bent into shape. In Table 1, the transfer mold has two upper and lower molds and a heat-resistant cloth, which means that the heat-resistant cloth is arranged between the upper and lower molds and the glass plate. η is the glass viscosity (dPa·s) corresponding to the forming temperature. The heating rate was set to reach the molding temperature from room temperature within 4 hours. The forming time is the time during which the glass sheet is heated at the forming temperature.

In Table 1, Ra is the arithmetic mean roughness recorded in Japanese Industrial Standard JIS B0601:2013, and Wa is the arithmetic mean waviness recorded in Japanese Industrial Standard JIS B0601:2013. Ra and Wa were measured using a non-contact three-dimensional measuring device (NH-3MAS) manufactured by Mitaka Koki Co., Ltd. The measuring pitch is 0.4 μm, and the measuring range is 5000 μm. Ra was calculated by setting the critical value to 0.08 mm. Wa was calculated by setting the critical value to 0.8 mm.

Pin marks were assessed by Ra. The smaller the Ra, the smaller the pin mark and the better the pin mark evaluation. The evaluation of pin traces is "0" which means that Ra is 0 μm or more and less than 0.002 μm. The evaluation of the pin mark is "△" which means that Ra is 0.002 μm to 0.006 μm. The evaluation of pin traces as "×" indicates that Ra exceeds 0.006 μm.

Heaviness is assessed by Wa. The smaller Wa is, the smaller the fluctuation is, and the better the evaluation of fluctuation is. "0" in the evaluation of fluctuation indicates that Wa is 0 μm or more and less than 0.0003 μm. The evaluation of fluctuation as "△" indicates that Wa is 0.0003 μm to 0.001 μm. The evaluation of waviness is "×", indicating that Wa exceeds 0.001 μm.

In Table 1, the PV (Peak to Valley) value is the maximum height difference between the actual curved surface and the target curved surface. It is measured using the three-dimensional measuring machine ATOS (model: ATOS Triple scan III) manufactured by gom company.

Shape error is evaluated by PV value. The smaller the PV value, the smaller the shape error, and the better the evaluation of the shape error. The evaluation of shape error is "〇", indicating that the PV value is between 0 mm and 0.5 mm. Evaluation of shape error as "△" indicates that the PV value is greater than 0.5 mm and less than 1.5 mm. Evaluation of shape error as "×" indicates that the PV value exceeds 1.5 mm. When the PV value is 1.5 mm or less, designability as curved glass can be ensured. When the PV value is less than 0.5 mm, the fit between the curved glass for vehicles and the vehicle body can be improved.

The transmission images of the glass plates obtained in Examples 1 to 6 are shown in FIGS. 13(A) to (F). The transmission image of the glass plate is obtained by setting the light source on the opposite side to the screen and shooting the image displayed on the screen with the glass plate as the reference. The transmission images shown in Fig. 13(A)-(F) are binarized. The black color of the transmission image indicates pin marks.

From the results of Examples 1 to 2, it can be seen that by laying a heat-resistant cloth between the glass plate and the transfer mold, the pin traces can be reduced, and the waviness can be reduced, but the shape error is relatively large. The reason for the large shape error is that the heat-resistant cloth hinders the deformation of the glass plate due to its own weight. As the heat-resistant fabric, a nonwoven fabric containing stainless fiber was used.

Also, from the results of Example 1 and Example 3, it can be seen that even when a heat-resistant cloth is laid between the glass plate and the transfer mold, as long as the upper and lower molds are used as the transfer mold, the weight of the upper mold can also be adjusted. Pressing the glass plate can reliably bend the entire glass plate and reduce shape errors.

Furthermore, from the results of Examples 3 to 5, it can be seen that if the molding temperature is lowered, the pin marks can be made smaller and waviness can be made smaller. It was also found that even if the forming temperature is lowered, the shape error can be prevented from increasing if the glass plate is pressed by the weight of the upper mold.

Next, Table 2 shows the relationship between the pin pitch and the PV value when the glass plate was heated at 620° C. for 1,200 seconds. The relationship shown in Table 2 was obtained by viscoelastic analysis using commercially available analysis software (ABAQUS). Table 3 shows the physical properties of the glass used in the viscoelastic analysis.

[Table 2] Pin spacing [mm] PV value [mm] 40 4.33 30 1.50 20 0.43 10 0.46 7 0.20

[table 3] temperature [°C] 25 500 700 Young's modulus [MPa] 74258 69301 45928 Poisson's ratio 0.22 0.24 0.33 Density [kg/m ³ ] 2500 The physical properties shown in Table 3 are the physical properties of soda lime glass. Also, in Table 2, the PV value is the maximum height difference between the actual curved surface and the target curved surface after bending. The target surface is toric. In the toric surface, the cross-sectional shape perpendicular to the Y-axis direction is a curve with a curvature radius of 900 mm, and the cross-sectional shape perpendicular to the X-axis direction is a curved shape with a curvature radius of 2000 mm. The dimension of the X-axis direction of the glass plate before bending is 82 mm, the dimension of the Y-axis direction is 43 mm, and the dimension (thickness) of the Z-axis direction is 1.8 mm. The end face of the pin head is a hemispherical surface with a radius of 3 mm. The presence or absence of heat-resistant cloth is set to "None".

It can be seen from Table 2 that to keep the PV value below 1.5 mm, the pin spacing should be below 30 mm. It can also be seen that, in order to make the PV value 0.5 mm or less, the pin pitch should be 20 mm or less.

As mentioned above, although the manufacturing method and transfer mold of the glass plate of this invention were demonstrated, this invention is not limited to the said embodiment etc. Various changes, amendments, substitutions, additions, deletions, and combinations can be made within the scope described in the scope of patent application. Of course, they also belong to the technical scope of the present invention.

Although this invention was demonstrated in detail with reference to the specific embodiment, it is clear for those skilled in the art that various changes and correction can be added without deviating from the mind and range of this invention. This application is based on the Japanese patent application 2021-061398 for which it applied on March 31, 2021, The content is taken in here as a reference.

1: The first transfer mold 2: 1st pin group 3: The first fixing piece 4: The first master model 4A: 2nd Master Model 5: heat-resistant cloth 5A: heat-resistant cloth 6: Second transfer mold 7: The 2nd pin group 8: The second fixing piece 9: glass plate 11: guide rod 21: Pin 1 22: curved surface 23: side 24: angle 25: 1st intermediate shaft 26: 1st head 27: 1st flange 28: screw hole 29: hollow hole 31: 1st Outer Frame 32: The first movable wedge 33: 1st screw 34: 1st screw hole 35: 1st arrangement of holes 36: The first arrangement board 37: Movable plate 38: Through hole 41: curved surface 41A: Surface 61: Guide hole 71: 2nd pin 72:Surface 73: side 74: Angle 75: Second intermediate shaft 76: 2nd head 77: 2nd flange 78: screw hole 79: hollow hole 81: Second outer frame 82: The second movable wedge 83: 2nd screw 84: 2nd screw hole 85: 2nd arrangement of holes 86: The second arrangement board 87: Mounting plate 88: Bolt P: Pitch

Fig. 1 is a flowchart showing a method of manufacturing a glass plate according to an embodiment. Fig. 2 is a perspective view showing an example of the first transfer mold. Fig. 3 is a view obtained by observing the first transfer mold of Fig. 2 from above. Fig. 4 is a cross-sectional view along line IV-IV of Fig. 3 . FIG. 5 is a cross-sectional view showing an example of step S102 in FIG. 1 . FIG. 6 is a cross-sectional view showing an example of step S104 in FIG. 1 . FIG. 7 is a cross-sectional view showing an example of step S105 in FIG. 1 . Fig. 8 is a sectional view showing an example of the second transfer mold. FIG. 9 is a cross-sectional view showing a modification example of step S102 in FIG. 1 . FIG. 10 is a cross-sectional view showing a modification example of step S104 in FIG. 1 . FIG. 11 is a cross-sectional view showing a modification example of step S105 in FIG. 1 . Fig. 12 is a sectional view showing a modified example of the fixing member. Figure 13 (A) is the transmission image of the glass plate obtained in Example 1, Figure 13 (B) is the transmission image of the glass plate obtained in Example 2, and Figure 13 (C) is the transmission image of the glass plate obtained in Example 3 The transmission image of the glass plate, Figure 13 (D) is the transmission image of the glass plate obtained in Example 4, Figure 13 (E) is the transmission image of the glass plate obtained in Example 5, Figure 13 (F) Transmission image of the glass plate obtained in Example 6.

1: The first transfer mold

2: 1st pin group

3: The first fixing piece

5: heat-resistant cloth

9: glass plate

21: Pin 1

25: 1st intermediate shaft

26: 1st head

27: 1st flange

31: 1st Outer Frame

32: The first movable wedge

33: 1st screw

34: 1st screw hole

35: 1st arrangement of holes

36: The first arrangement board

Claims (21)

A method of manufacturing a glass plate, which includes a method of manufacturing a glass plate in a curved shape, and Including the following steps: Prepare the first transfer mold with the first pin group, the first pin group includes three or more first pins that are independently movable along the length direction and parallel to each other; Make the head end of each of the above-mentioned first pins touch the curved surface of the first original mold, adjust and fix the position of each of the above-mentioned first pins; In the state where the position of each of the above-mentioned first pins has been fixed, separate each of the above-mentioned first pins from the above-mentioned first master mold; Place the glass plate on the above-mentioned first transfer mold with the above-mentioned head end of each of the above-mentioned fixed first pins facing upward; and The above-mentioned glass plate is heated, and the above-mentioned glass plate is bent and formed along the above-mentioned head end of each of the above-mentioned fixed first pins. The manufacturing method of the glass plate according to claim 1, which is to bend the glass plate into shape by the self-weight of the glass plate. The method of manufacturing a glass plate according to claim 1, which is to bend the glass plate into shape by the self-weight and air pressure of the glass plate. The method of manufacturing a glass plate according to claim 1, which is to press the upper mold disposed on the above-mentioned glass plate downward by a press machine, and clamp the glass by the above-mentioned upper mold and the above-mentioned first transfer mold Plates are press-formed. As the manufacturing method of the glass plate of claim 1, it comprises the following steps: Prepare the second transfer mold with the second pin group, the above-mentioned second pin group includes three or more second pins that are independently movable along the length direction and parallel to each other; Make the head end of each of the above-mentioned second pins touch the curved surface of the second original mold, adjust and fix the position of each of the above-mentioned second pins; In the state where the position of each of the above-mentioned second pins is fixed, separate each of the above-mentioned second pins from the above-mentioned second master mold; placing the above-mentioned second transfer mold on the above-mentioned glass plate with the above-mentioned heads of the above-mentioned fixed second pins facing down; and The above-mentioned glass plate is bent and formed along the above-mentioned head end of each of the above-mentioned fixed second pins. The method for manufacturing a glass plate as claimed in claim 5, which includes the following steps: fixing the guide rod to one of the first transfer mold and the second transfer mold, and fixing the guide hole to the first transfer mold. The other one of the impression mold and the above-mentioned second transfer mold, By inserting the guide rod into the guide hole, the second transfer mold is guided vertically with respect to the first transfer mold. The method for manufacturing a glass plate according to any one of claims 1 to 5, wherein the head end of each of the first pins includes an upwardly convex dome-shaped curved surface, and the glass plate is supported by the curved surface. The method of manufacturing a glass plate according to any one of claims 1 to 7, wherein the distance between the center lines of the fixed adjacent first pins is 5 mm to 30 mm. The method for manufacturing a glass plate according to any one of Claims 1 to 8, which includes the following steps: laying a heat-resistant cloth between the first pin group and the glass plate. The method for manufacturing a glass plate as claimed in claim 9, wherein the thickness of the above-mentioned heat-resistant cloth is 0.3 mm to 1.0 mm, the surface density is 100 g/m ² to 1400 g/m ² , and the air permeability is 20 cc/(cm ² ·sec )～200 cc/(cm ² ·sec). A method for manufacturing a glass plate according to any one of claims 1 to 10, wherein when the above-mentioned glass plate is bent and shaped, the above-mentioned glass plate is heated at a preset forming temperature, and the above-mentioned forming temperature is set in the viscosity range of the glass. Within the temperature range of 10 ⁸ Pa·s～10 ¹² Pa·s. A transfer mold, which is used to manufacture a glass plate with a curved surface shape, and has: A pin group comprising three or more pins that are independently free to move along their length and are parallel to each other; and Fixing member, which maintains the position of each of the above-mentioned pins so that they can be moved. The transfer mold according to claim 12, wherein the above-mentioned fixing member includes: an outer frame surrounding the above-mentioned pin group; and a movable wedge protruding inwardly of the above-mentioned outer frame so that the adjacent above-mentioned pins are pressed against each other. The transfer mold according to claim 13, wherein the above-mentioned fixing part further includes a screw that pushes the above-mentioned pin through the above-mentioned movable wedge, The above-mentioned outer frame includes screw holes for the above-mentioned screws to be screwed into. The transfer mold according to claim 13, wherein the above-mentioned fixing part further includes a cylinder that pushes the above-mentioned pin through the above-mentioned movable wedge. The transfer mold according to any one of claims 13 to 15, wherein the above-mentioned fixing part includes a mounting plate for mounting heat-resistant cloth on the above-mentioned outer frame. The transfer mold according to any one of Claims 12 to 16, wherein the above-mentioned fixing member includes an arrangement plate, and the arrangement plate is formed with a plurality of insertion holes through which the above-mentioned pins are inserted one by one. Such as the transfer mold of claim 17, wherein the above-mentioned pin includes: an intermediate shaft, which is inserted into the above-mentioned insertion hole; a head, which is removably mounted on one end of the above-mentioned intermediate shaft in the longitudinal direction; and a flange, which It is arranged at the other end in the longitudinal direction of the above-mentioned intermediate shaft; and it is arranged so that the above-mentioned head faces the above-mentioned glass plate. The transfer mold according to any one of claims 12 to 18, wherein the above-mentioned pin has a hollow structure. The transfer mold according to any one of claims 12 to 19, wherein the head end of each of the above-mentioned pins includes a dome-shaped curved surface, and the above-mentioned glass plate is supported by the curved surface. The transfer mold according to any one of claims 12 to 20, wherein the distance between the centerlines of adjacent pins is 5 mm to 30 mm when the pins are fixed by the fixing member.

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