KR102140926B1 - Support roller, method for molding glass plate, method for manufacturing glass plate, and device for manufacturing glass plate - Google Patents

Abstract

[Solutions] As a support roll for supporting a glass ribbon on a strip, there is a rotating member in contact with the glass ribbon, a refrigerant passage therein, and a shaft member rotating together with the rotating member, the rotating member being ceramics It is formed of, between the outer periphery of the shaft member and the inner periphery of the rotating member that is inserted into the through-hole of the rotating member, the first insulating member having a lower thermal conductivity than the rotating member is disposed support roll.

Description

Support roll, glass plate forming method, glass plate manufacturing apparatus, and glass plate manufacturing method {SUPPORT ROLLER, METHOD FOR MOLDING GLASS PLATE, METHOD FOR MANUFACTURING GLASS PLATE, AND DEVICE FOR MANUFACTURING GLASS PLATE}

The present invention relates to a support roll, a method for forming a glass plate, a device for manufacturing a glass plate, and a method for manufacturing a glass plate.

The forming method of a glass plate has a process of shape|molding molten glass into a strip-shaped glass ribbon. Glass ribbons thinner than the equilibrium thickness tend to shrink in the width direction. Therefore, in order to keep the thickness of the glass ribbon at a desired thickness, a support roll that applies a tension in the width direction to the glass ribbon is used (for example, see Patent Document 1). The support rolls are used in pairs, pressing against both edge portions of the glass ribbon. A plurality of pairs of support rolls are arranged at intervals along the moving direction of the glass ribbon. The support roll has a rotating member in contact with the glass ribbon at the tip, and the rotating member rotates, whereby the glass ribbon is discharged in a predetermined direction. The glass ribbon gradually cools and solidifies while moving in a predetermined direction.

Japanese Patent Application Publication No. 2011-225386

The conventional rotating member is formed of a metal material and has low heat resistance. On the other hand, there is a problem that the rotating member formed of ceramics is easily cracked by a temperature gradient.

This invention is made|formed in view of the said subject, and aims at providing the support roll which can suppress the crack of the rotating member made from ceramics.

In order to solve the above problems, according to an aspect of the present invention,

As a support roll supporting a glass ribbon on a strip,

A rotating member in contact with the glass ribbon,

Has a refrigerant passage therein, and has an axial member rotating together with the rotating member,

The rotating member is formed of ceramics,

A support roll is provided between the outer periphery of the shaft member inserted into the through hole of the rotating member and the inner periphery of the rotating member, wherein a first heat insulating member having a lower thermal conductivity than the rotating member is disposed.

According to one aspect of the present invention, it is possible to provide a support roll capable of suppressing cracking of a rotating member made of ceramics.

1 is a partial cross-sectional view showing an apparatus for forming a glass plate according to a first embodiment of the present invention.
FIG. 2 is a plan view showing a lower structure of the molding apparatus of the glass plate of FIG. 1.
3 is a cross-sectional view showing a support roll according to a first embodiment of the present invention.
4 is a cross-sectional view showing a support roll according to a second embodiment of the present invention.
5 is a graph showing the change in time of wettability of molten glass with respect to the sintered bodies according to Examples 1 to 4.
6 is a cross-sectional view showing a rotating member according to a modification.
Fig. 7 is a view showing the dimensions of the convex shape of the rotating member of Fig. 6;
Fig. 8 is a view showing the dimensions of the convex shape of the rotating member of Fig. 6;
9 is a cross-sectional view showing a rotating member according to another modification.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings. In the following drawings, the same or corresponding reference numerals are assigned to the same or corresponding structures, and the description is omitted.

[First Embodiment]

1 is a partial cross-sectional view showing an apparatus for forming a glass plate according to a first embodiment of the present invention. FIG. 2 is a plan view showing a lower structure of the molding apparatus of the glass plate of FIG. 1.

The shaping|molding apparatus 10 molds molten glass into the strip-shaped glass ribbon 14. The molding apparatus 10 is equipped with the bath 20 which accommodates molten metal (for example, molten tin) 16, and the molten glass 16 continuously supplied on the molten metal 16 is melted metal 16 It flows in a predetermined direction (in the X direction in Fig. 2) on the bed to form a strip-shaped glass ribbon 14. The glass ribbon 14 is cooled in the process of flowing in a predetermined direction (in the X direction in FIG. 2 ), then lifted from the molten metal 16 by a lift-out roll, and slowly cooled in a slow cooling furnace to form a plate glass. Becomes. After being taken out of the slow cooling furnace, the plate-shaped glass is cut into a predetermined dimensional shape by a cutter, thereby forming a product glass plate.

The forming apparatus 10 includes a bath 20 accommodating the molten metal 16, a ceiling 22 formed above the bath 20, and a side wall closing the gap between the bath 20 and the ceiling 22. (24) and the like. A gas supply path 32 is formed in the ceiling 22, and a heater 34 as a heating source is inserted through the gas supply path 32.

The gas supply passage 32 supplies a reducing gas to the space above the molten metal 16 to prevent oxidation of the molten metal 16. The reducing gas contains, for example, 1 to 15% by volume of hydrogen gas and 85 to 99% by volume of nitrogen gas.

The heater 34 is spaced apart in the moving direction and the width direction of the glass ribbon 14, and is formed in multiple numbers above the molten metal 16 and the glass ribbon 14. The output of the heater 34 is controlled such that the temperature of the glass ribbon 14 decreases as it goes from the upstream side to the downstream side. Moreover, the output of the heater 34 is controlled so that the thickness of the glass ribbon 14 becomes uniform in the width direction (Y direction).

The shaping|molding apparatus 10 has the support roll 40 used for suppression of shrinkage in the width direction of the strip-shaped glass ribbon 14. The support rolls 40 are used in pairs, pressing against both edge portions of the glass ribbon 14. A plurality of pairs of support rolls 40 are arranged at intervals along the moving direction of the glass ribbon 14. The support roll 40 has a rotating member 42 in contact with the glass ribbon 14 at the distal end, and the glass ribbon 14 is discharged in a predetermined direction as the rotating member 42 rotates. The glass ribbon 14 gradually cools and hardens while moving in a predetermined direction.

3 is a cross-sectional view showing a support roll according to a first embodiment of the present invention. The support roll 40 includes a rotating member 42, a shaft member 44, a flange 46 as a extending member, a heat transfer member 48, a pressing member 50, a first elastic body 54, and a heat insulating member 60 ), shim fitting member 64, second elastic body 66, and the like.

In order to suppress the slip on the glass ribbon 14, the rotating member 42 may have a gear-shaped unevenness 43 contacting the glass ribbon 14 on the outer circumference, for example, as shown in FIG. do. Although the shape of the convex portion of the gear-shaped unevenness 43 is not particularly limited, as shown in, for example, FIG. 3, the tip may be formed in a thin shape (for example, a quadrangular shape). As shown in Fig. 1, the gear-shaped irregularities 43 are formed in a line in the thickness direction (Y direction in Fig. 1) of the outer circumference of the rotating member 42, but may be formed in plural rows.

The rotating member 42 does not have a refrigerant passage inside. In addition, since the shaft member 44 inserted and passed through the through-hole of the rotating member 42 is a member different from the rotating member 42, the refrigerant passage 45 formed in the shaft member 44 is the rotating member 42 It is a refrigerant flow path formed on the outside.

The rotating member 42 is formed of ceramics having higher heat resistance than a metal material. The ceramics of the rotating member 42 are not particularly limited, but, for example, silicon carbide (SiC) quality ceramics, silicon nitride (Si ₃ N ₄ ) quality ceramics, and the like are used. Silicon carbide and silicon nitride have high resistance to splashing of the molten metal 16 and vapor of the molten metal 16, and are excellent in high temperature strength and creep characteristics.

The type of ceramics of the rotating member 42 is selected according to the type of glass or the like. For example, in the case of an alkali-free glass, since the molding temperature of the glass is high, silicon nitride ceramics excellent in heat shock resistance are preferable. Silicon nitride ceramics are also excellent in that they have low reactivity with alkali-free glass. On the other hand, in the case of soda-lime glass, in addition to silicon nitride ceramics, silicon carbide ceramics or alumina ceramics can be used.

In the case of an alkali free glass, at least a portion of the rotating member 42 that contacts the glass ribbon 14 may be silicon nitride ceramics, and the entire rotating member 42 may not be silicon nitride ceramics. For example, a layer of silicon nitride ceramics may be formed on a substrate made of ceramics other than silicon nitride ceramics.

The silicon nitride ceramics may be a sintered body obtained by sintering a molded body made of a mixed powder containing a powder of silicon nitride and a powder of a sintering aid. Examples of the sintering method include an atmospheric pressure sintering method and a pressure sintering method (including hot press sintering and gas pressure sintering). As the sintering aid, for example, at least one kind selected from alumina (Al ₂ O ₃ ), magnesia (MgO), titania (TiO ₂ ), zirconia (ZrO ₂ ), and yttria (Y ₂ O ₃ ) Is used.

Silicon nitride ceramics have an aluminum (Al) content of 0.1 mass% or less, preferably less than 1 mass%, a magnesium (Mg) content of 0.7 mass% or less, preferably less than 0.7 mass%, of titanium (Ti). Content should be 0.9 mass% or less, preferably less than 0.9 mass %. When the Al content, Mg content, and Ti content are within the above range, the reactivity between the rotating member 42 and the glass ribbon 14 is low, and the rotating member 42 and the glass ribbon 14 do not adhere well, and good durability This is obtained. Al content, Mg content, and Ti content may be 0 mass%, respectively.

Silicon nitride ceramics have a content of zirconium (Zr) of 3.5 mass% or less, preferably less than 3.5 mass%, a content of yttrium (Y) of 0.5 mass% or more, preferably more than 0.5 mass%, 10 mass% or less, Preferably, it should just be less than 10 mass%. Zr or Y may be contained in the above range because they are components that are less likely to diffuse with the glass ribbon 14 than Al, Mg, and Ti. By being contained in the above range, sintering of the silicon nitride powder can be promoted. Zr is an optional component, and the Zr content may be 0 mass%.

In addition, although the silicon nitride ceramics of this embodiment were said to be a sintered body obtained by a normal pressure sintering method or a pressure sintering method, it may be a sintered body obtained by a reaction sintering method. The reaction sintering method is a method of heating a molded body formed of a powder of metal silicon (Si) in a nitrogen atmosphere. Since the reaction sintering method does not use a sintering aid, a high-purity sintered body is obtained, and durability of the sintered body to the glass ribbon 14 can be improved.

Although the glass plate which is a product is not specifically limited, For example, it may be for flat panel displays (FPD), such as a liquid crystal display (LCD), a plasma display (PDP), and an organic EL display. In recent years, thinning of FPD is advancing, and thinning of the glass plate for FPD is advancing. In particular, in the case of a glass plate for a display substrate, a glass plate of preferably 0.7 mm or less, more preferably 0.3 mm or less, further preferably 0.2 mm or less, and particularly preferably 0.1 mm or less is desired. Therefore, the thickness of the glass ribbon 14 becomes thin, the shrinking force in the width direction of the glass ribbon 14 becomes strong, and the forming temperature of the glass ribbon 14 increases. Although the support roll 40 of this embodiment is mentioned in detail later, between the outer periphery of the shaft member 44 and the inner periphery of the rotating member 42 which are inserted and passed through the through hole of the rotating member 42, a rotating member ( 42) Since the heat insulating member 60 having a lower thermal conductivity is disposed, it is possible to suppress cracking of the rotating member 42, which is suitable for forming a glass plate for FPD.

The kind of glass plate which is a product is not specifically limited. The composition of the glass plate is SiO ₂ : 50 to 75%, Al ₂ O ₃ : 0.1 to 24%, B ₂ O ₃ : 0 to 12%, MgO: 0 to 10, for example, in terms of oxide-based mass%. %, CaO: 0-14.5%, SrO: 0-24%, BaO: 0-13.5%, Na ₂ O: 0-20%, K ₂ O: 0-20%, ZrO ₂ : 0-5%, MgO + CaO + SrO + BaO: 5 to 29.5%, Na ₂ O + K ₂ O: 0 to 20%.

The glass plate may be formed of, for example, alkali-free glass. The alkali-free glass is a glass substantially free of alkali metal oxides (Na ₂ O, K ₂ O, Li ₂ O, etc.). In the alkali-free glass, the total amount of the content of the alkali metal oxide may be 0.1 mass% or less.

For the alkali-free glass, for example, in terms of oxide-based mass%, SiO ₂ : 50 to 70% (preferably 50 to 66%), Al ₂ O ₃ : 10.5 to 24%, B ₂ O ₃ : 0 -12%, MgO: 0-10% (preferably 0-8%), CaO: 0-14.5%, SrO: 0-24%, BaO: 0-13.5%, ZrO ₂ : 0-5%, MgO + CaO + SrO + BaO: 8 to 29.5% (preferably 9 to 29.5%).

When the alkali-free glass is compatible with a high strain point and high solubility, preferably in terms of oxide-based mass%, SiO ₂ : 58 to 66%, Al ₂ O ₃ : 15 to 22%, B ₂ O ₃ : 5 to 12%, MgO: 0 to 8%, CaO: 0 to 9%, SrO: 3 to 12.5%, BaO: 0 to 2%, MgO + CaO + SrO + BaO: 9 to 18%.

For the alkali-free glass, particularly when a high strain point is to be obtained, preferably in terms of oxide-based mass%, SiO ₂ : 54 to 73%, Al ₂ O ₃ : 10.5 to 22.5%, B ₂ O ₃ : 0 ∼ 5.5%, MgO: 0 to 10%, CaO: 0 to 9%, SrO: 0 to 16%, BaO: 0 to 2.5%, MgO + CaO + SrO + BaO: 8 to 26%.

The shaft member 44 penetrates the side wall 24 as shown in FIG. 1, and is connected to the drive device 36 which is disposed outside the side wall 24. The drive device 36 is composed of a motor, a reduction gear, or the like, and rotates the shaft member 44 around the center line of the shaft member 44. The shaft member 44 is inserted through a through hole formed in the central portion of the rotating member 42 and rotates together with the rotating member 42.

The shaft member 44 may be formed in a cylindrical shape, for example, of a metal material, and has a refrigerant passage 45 therein through which refrigerant such as water passes. The refrigerant may be a fluid, or air or the like.

The flange 46 may be formed integrally with the shaft member 44. The flange 46 is extended in the radial direction of the rotating member 42 from the outer periphery of the shaft member 44 in the middle of the shaft member 44. On the inner circumference of the flange 46, a branch path 47 is branched from the refrigerant passage 45 of the shaft member 44, and the branch path 47 extends to the vicinity of the outer circumference of the flange 46. The flange 46 is cooled by the refrigerant passing through the branch path 47.

The heat transfer member 48 is formed in a ring shape, for example. The inner diameter of the heat transfer member 48 is larger than the outer diameter of the shaft member 44, and the heat transfer member 48 does not contact the shaft member 44. The heat transfer member 48 is positioned by a positioning groove 49 formed on a side surface of the flange 46 on the side of the rotating member 42.

The heat transfer member 48 is formed between the flange 46 and the rotation member 42, has a higher thermal conductivity than the rotation member 42, and flanges the heat of the rotation member 42 transmitted from the glass ribbon 14 (46). The outer circumference of the rotating member 42 is maintained at a temperature such that it does not stick to the glass ribbon 14, and the rotation torque can be reduced.

Here, the thermal conductivity of the heat transfer member 48 and the thermal conductivity of the rotating member 42 are measured at the operating temperature of the support roll 40. In the use temperature of the support roll 40, the thermal conductivity of the heat transfer member 48 is preferably 30 to 200 W/(m·°C).

Since the flange 46 cools the heat transfer member 48 and the heat transfer member 48 cools the rotating member 42 from the side, the rotating member 42 is compared to the case where the rotating member 42 is cooled from the inner circumference ), the temperature gradient in the radial direction becomes gentle, and damage due to thermal stress of the rotating member 42 can be suppressed.

The heat transfer member 48 only needs to have a higher thermal conductivity than the rotation member 42, and is formed of, for example, metal, carbon, or the like. Metal or carbon is softer than ceramics, and the heat transfer member 48 and the rotation member 42 are more likely to be in close contact. Therefore, the contact heat resistance is low and the heat transfer efficiency is good. Carbon is particularly preferred from the viewpoint of heat resistance.

When the heat transfer member 48 is formed of the same material as the flange 46, the heat transfer member 48 and the flange 46 may be integrally formed.

The pressing member 50 presses the rotating member 42 against the heat transfer member 48 and lowers the contact heat resistance between the heat transfer member 48 and the rotating member 42. The pressing member 50 is disposed on the opposite side to the heat transfer member 48 based on the rotating member 42.

The pressing member 50 is composed of, for example, a pressing member body 51 and a contact portion 52. The pressing member body 51 is formed of, for example, a metal, and the shaft member 44 is inserted through a through hole formed in the central portion of the pressing member body 51. The contact portion 52 may be formed in a ring shape like the heat transfer member 48. The outer diameter of the contact portion 52 is larger than the inner diameter of the shaft member 44, and the contact portion 52 does not contact the shaft member 44 and the opposite side of the contact portion of the heat transfer member 48 in the rotating member 42 Press intensively. The contact portion 52 is formed of metal or carbon. Carbon is particularly preferred from the viewpoint of heat resistance. The contact portion 52 is positioned by a positioning groove 53 formed on a side surface of the pressing member main body 51 on the side of the rotating member 42. When the contact portion 52 is formed of the same material as the pressing member body 51, the contact portion 52 and the pressing member body 51 may be integrally formed.

The first elastic body 54 elastically supports the pressing member 50 that can be freely displaced in the axial direction of the shaft member 44 toward the rotating member 42. The first elastic body 54 is composed of, for example, a plate spring, and the shaft member 44 is inserted through a through hole formed in the first elastic body 54. The shaft member 44 has a screw shaft portion 44a, and the first elastic body 54 is reduced from the natural state between the first nut 58 and the rotating member 42 that are screwed to the screw shaft portion 44a. The batch is formed. When a dimensional change occurs due to temperature change or the like, the rotating member 42 is always pressed against the heat transfer member 48 by the pressing member 50.

Moreover, although the 1st elastic body 54 of this embodiment is comprised with a plate spring, you may be comprised with a coil spring, and the structure of the 1st elastic body 54 is not specifically limited. Further, the first elastic body 54 may be omitted, and in this case, by tightening the first nut 58, the first nut 58 presses the pressing member 50, and the pressing member 50 presses the rotating member 42. Pressure is applied to the heat transfer member 48.

The heat insulating member 60 is normally formed, for example. The heat insulating member 60 may be divided into a plurality of divided bodies (for example, two half bodies) in the circumferential direction from the viewpoint of processability and cost.

The heat insulating member 60 is disposed between the inner circumference of the rotating member 42 and the outer circumference of the shaft member 44, has a lower thermal conductivity than the rotating member 42, and the heat of the rotating member 42 is axial member ( 44) Suppressing the escape to. The temperature gradient in the radial direction of the rotating member 42 becomes more gentle, and damage due to thermal stress of the rotating member 42 can be suppressed.

Here, the thermal conductivity of the heat insulating member 60 and the thermal conductivity of the rotating member 42 are measured at the use temperature of the support roll 40. In the use temperature of the support roll 40, the thermal conductivity of the heat insulating member 60 is preferably 0.01 to 30 W/(m·°C).

The material of the heat insulating member 60 is not particularly limited as long as it has a lower thermal conductivity than the material of the rotating member 42, but, for example, slate or the like is used. The slate may be, for example, a natural slate made of rocks such as slate, or an artificial slate in which a fiber material is mixed with cement.

The outer circumferential surface of the heat insulating member 60 is a contact surface in contact with the inner circumferential surface of the rotating member 42 and has a tapered shape that decreases in diameter toward the flange 46 along the center line of the rotating member 42. Similarly, the inner circumferential surface of the rotating member 42 is a contact surface in contact with the outer circumferential surface of the heat insulating member 60 and has a tapered shape that decreases in diameter toward the flange 46 along the center line of the rotating member 42. If at least one of the contact surfaces of the heat insulating member 60 and the rotating member 42 in contact with each other is a tapered shape, adhesion between the heat insulating member 60 and the rotating member 42 can be reduced. In addition, the direction of the taper may be reverse, and each contact surface may have a tapered shape that increases in diameter as it faces the flange 46 along the center line of the rotating member 42.

The shim fitting member 64 aligns the center line of the heat insulating member 60 with the center line of the shaft member 44, and is usually formed, for example, and has an inner circumference of the heat insulating member 60 and an outer circumference of the shaft member 44. It is arranged between. The shim fitting member 64 may be formed of a metal similar to the shaft member 44. Since the thermal expansion difference between the shim fitting member 64 and the shaft member 44 is small, the clearance between the shim fitting member 64 and the shaft member 44 can be set narrow, and the shim fitting member 64 and the shaft member 44 are The sticking of the can be reduced.

The shim fitting member 64 serves to align the positions of the plurality of divisions when the heat insulating member 60 is divided into a plurality of divisions in the circumferential direction.

The outer circumferential surface of the shim fitting member 64 is a contact surface in contact with the inner circumferential surface of the heat insulating member 60 and has a tapered shape that decreases in diameter toward the flange 46 along the center line of the rotating member 42. Similarly, the inner circumferential surface of the heat insulating member 60 is a contact surface in contact with the outer circumferential surface of the shim fitting member 64 and has a tapered shape that decreases in diameter toward the flange 46 along the center line of the rotating member 42. If at least one of the contact surfaces of the shim fitting member 64 and the heat insulating member 60 in contact with each other is a tapered shape, sticking of the shim fitting member 64 and the heat insulating member 60 can be reduced. In addition, the direction of the taper may be reverse, and each contact surface may have a tapered shape that increases in diameter as it faces the flange 46 along the center line of the rotating member 42.

Further, in the present embodiment, the shim fitting member 64 is disposed between the inner circumference of the heat insulating member 60 and the outer circumference of the shaft member 44, but the shim fitting member 64 may not be provided, and the heat insulating member 60 There may be some clearance between the inner circumference of and the outer circumference of the shaft member 44.

The second elastic body 66 is a heat insulating member 60 that can be freely displaced in the axial direction of the shaft member 44 via a shim fitting member 64 that can be freely displaced in the axial direction of the shaft member 44. ) Toward the flange 46 to elastically support. The second elastic body 66 is composed of, for example, a plate spring, and the shaft member 44 is inserted through a through hole formed in the second elastic body 66. The second elastic body 66 is disposed between the second nut 68 and the shim fitting member 64 screwed to the screw shaft portion 44a of the shaft member 44 in a reduced state than the natural state. When the dimensional change occurs due to temperature change or the like, the separation between the shim fitting member 64 and the heat insulating member 60 can be prevented, and the separation between the heat insulating member 60 and the rotating member 42 can be prevented. .

In addition, although the 2nd elastic body 66 of this embodiment is comprised with a plate spring, you may be comprised with a coil spring, and the structure of the 2nd elastic body 66 is not specifically limited. In the absence of the shim fitting member 64, the second elastic body 66 contacts the heat insulating member 60 and elastically supports the heat insulating member 60 by facing the flange 46. In addition, the second elastic body 66 may be omitted, and in this case, by tightening the second nut 68, the shim fitting member 64 and the heat insulating member 60 are close, and the heat insulating member 60 and the rotating member ( 42) is close.

When the moldability of the glass ribbon 14 is considered in the support roll 40 of this embodiment, the forming range of the molding apparatus 10 (the glass ribbon 14 has a viscosity range of 10 ^4.5 to 10 ^7.5 dPa·s) Zone). In the case of an alkali free glass, the viscosity range in which the glass ribbon 14 is 10 ^4.5 to 10 ^7.5 dPa·s corresponds to the temperature range of the glass ribbon 14 in the range of 946 to 1200°C.

In addition, the support roll 40 may be used in combination with a support roll having a general configuration, or may be used in a part of the forming station.

[Second Embodiment]

The support roll of the first embodiment has a heat transfer member 48 having a higher thermal conductivity than the rotation member 42 between the flange 46 and the rotation member 42. On the other hand, the support roll of this embodiment has a heat-insulating member with a lower thermal conductivity than the rotating member between the flange and the rotating member. The support roll of the present embodiment tends to be at a high temperature and easily adheres to the glass ribbon 14, as heat does not escape more easily than the support roll of the first embodiment. Therefore, in the molding apparatus 10, the support rolls of the present embodiment, a low temperature (glass ribbon 14 on the downstream side of the support roll of the first embodiment 10 ^7.5 more than ~ 10 ^7.65 dPa · s in viscosity range It may be used in the region. In the case of an alkali free glass, the viscosity range in which the glass ribbon 14 is more than 10 ^7.5 to 10 ^7.65 dPa·s corresponds to a temperature range of 937°C or more and less than 946°C.

4 is a cross-sectional view showing a support roll according to a second embodiment of the present invention. The support roll 140 includes a rotating member 142, a shaft member 144, a flange 146 as a extending member, a second insulating member 148, a first insulating member 160, a shim fitting member 164, And an elastic body 166.

The rotating member 142 is configured similarly to the rotating member 42 shown in FIG. 3 and the like.

The shaft member 144 is configured similarly to the shaft member 44 shown in FIG. 3 and the like, is inserted into a through hole formed in the central portion of the rotary member 142, and rotates together with the rotary member 142. The shaft member 144 has a refrigerant passage 145 therein through which refrigerant such as water passes.

The flange 146 may be formed integrally with the shaft member 144. The flange 146 is extended in the radial direction of the rotating member 142 from the outer periphery of the shaft member 144 in the middle of the shaft member 144. On the inner circumference of the flange 146, a branch path 147 branching off from the refrigerant passage 145 of the shaft member 144 is formed, and the branch path 147 extends to the vicinity of the outer circumference of the flange 146. The flange 146 is cooled by the refrigerant passing through the branch path 147.

The second heat insulating member 148 is formed in a ring shape, for example. The inner diameter of the second heat insulating member 148 is larger than the outer diameter of the shaft member 144, and the second heat insulating member 148 does not contact the shaft member 144. The second heat insulating member 148 is positioned by a positioning groove 149 formed on a side surface of the flange 146 on the side of the rotating member 142.

The second heat insulating member 148 is formed between the rotating member 142 and the flange 146, has a lower thermal conductivity than the rotating member 142, and the heat of the rotating member 142 transferred from the glass ribbon 14 It is restrained to escape to the flange 146. The rotating member 142 is difficult to cool from the side, and the glass ribbon 14 is hard to cool due to contact with the rotating member 142, so it is hard to harden. Thereby, it is easy for the rotating member 142 to press the glass ribbon 14, and it is easy to suppress the contraction of the glass ribbon 14 in the width direction. It is particularly effective for the portion where the temperature of the glass ribbon 14 is low.

Here, the thermal conductivity of the second heat insulating member 148 and the thermal conductivity of the rotating member 142 are measured at the use temperature of the support roll 140. At the use temperature of the support roll 140, the thermal conductivity of the second heat insulating member 148 is preferably 0.01 to 30 W/(m·°C).

The material of the second heat insulating member 148 is not particularly limited as long as it is a material having a lower thermal conductivity than the rotating member 142, but, for example, slate or the like is used.

It is not necessary that the second heat insulating member 148 and the rotating member 142 are in close contact, and there may be no members corresponding to the pressure member 50 and the first elastic body 54 of the first embodiment.

The 1st heat insulating member 160 is comprised similarly to the heat insulating member 60 shown in FIG. 3, etc., and is arrange|positioned between the inner periphery of the rotating member 142 and the outer periphery of the shaft member 144, and the rotating member 142 It has a lower thermal conductivity and suppresses heat from the rotating member 142 from escaping to the shaft member 144. The temperature gradient in the radial direction of the rotating member 142 becomes more gentle, and damage due to thermal stress of the rotating member 142 can be suppressed.

The shim fitting member 164 is configured in the same manner as the shim fitting member 64 shown in FIG. 3 and the like, and fits the center line of the first heat insulating member 160 and the center line of the shaft member 144, for example, normally It is formed and is disposed between the inner circumference of the first heat insulating member 160 and the outer circumference of the shaft member 144.

Further, in the present embodiment, the shim fitting member 164 is disposed between the inner circumference of the first heat insulating member 160 and the outer circumference of the shaft member 144, but the shim fitting member 164 may be omitted, and the first heat insulating There may be some clearance between the inner circumference of the member 160 and the outer circumference of the shaft member 144.

The elastic body 166 is configured in the same manner as the second elastic body 66 shown in FIG. 3 and the like, and the shaft member 144 is provided through a shim fitting member 164 that can be freely displaced in the axial direction of the shaft member 144. ) The first heat insulating member 160 that can be freely displaced in the axial direction is elastically supported toward the flange 146. The elastic body 166 is composed of, for example, a plate spring, and the shaft member 144 is inserted through a through hole formed in the elastic body 166. The elastic body 166 is disposed between the nut 168 screwed to the screw shaft portion 144a of the shaft member 144 and the shim fitting member 164 in a reduced state than the natural state.

In addition, although the elastic body 166 of this embodiment is comprised with a dish spring, it may be comprised with a coil spring, and the structure of the elastic body 166 is not specifically limited. In the absence of the shim fitting member 164, the elastic body 166 contacts the first heat insulating member 160 and elastically supports the first heat insulating member 160 toward the flange 146. Further, the elastic body 166 may not be provided, and in this case, by tightening the nut 168, the shim fitting member 164 and the first heat insulating member 160 are close, and the first heat insulating member 160 and the rotating member ( 142) is close.

Example

In Examples 1 to 4, the relationship between the wettability of the sintered body with respect to the molten glass and the impurities contained in the sintered body was investigated.

Test pieces and test plates for evaluation were prepared by processing a sintered body of silicon nitride (Si ₃ N ₄ ) quality ceramics different for each example.

The content of impurities in the sintered body was measured by analyzing a test piece cut out from the sintered body into a phase by a glow discharge mass spectrometry. The impurities to be measured are contained as a sintering aid, and are aluminum (Al), magnesium (Mg), titanium (Ti), zirconium (Zr), and yttrium (Y).

The wettability of the sintered compact with respect to the molten glass was measured by a high-temperature wettability tester (manufactured by Albin Corporation, WET1200). Specifically, each glass piece of alkali-free glass (manufactured by Asahi Glass Co., Ltd. AN100) was placed on a test plate processed to a thickness of 1 mm, heated in a nitrogen atmosphere to 1150°C for 10 minutes, and heated to 1150°C. After maintaining at 10 minutes to produce molten glass, the temperature was lowered from 1150°C to 1050°C for 90 seconds and maintained at 1050°C to measure the contact angle of the droplets. The measurement was performed when the temperature dropped to 1050° C., and after 2 hours, after 4 hours, after 6 hours, and after 8 hours from that time. The larger the contact angle means that the molten glass is less likely to get wet with the sintered body, indicating that the reactivity between the molten glass and the sintered body is low. In addition, it means that the less the change in time of the contact angle, the easier it is to continue wet.

Table 1 and Fig. 5 show the results of the evaluation. In FIG. 5, the vertical axis represents the contact angle (°), and the horizontal axis represents the elapsed time (h: hours). Moreover, 10000 mass ppm is 1 mass %.

As is apparent from Table 1 and FIG. 5, the Al content is 0.1 mass% or less, preferably less than 0.1 mass%, the Mg content is 0.7 mass% or less, preferably less than 0.7 mass%, and the Ti content is 0.9 mass% or less, Preferably it is less than 0.9 mass%, Zr content is 3.5 mass% or less, preferably less than 3.5 mass%, Y content is 0.5 mass% or more, 10 mass% or less, preferably more than 0.5 mass%, less than 10 mass% , It is understood that good durability is obtained because the time change of the contact angle is small and the contact angle after 8 hours is large.

In the above, although the support roll, the manufacturing method of a glass plate, the embodiment of the manufacturing apparatus of a glass plate, etc. were demonstrated, this invention is not limited to the said embodiment. The present invention can be modified or improved within the scope of the scope of the claims.

For example, although the support roll 40 of the said embodiment is used in the float method of shaping the glass ribbon 14 on the molten metal 16, it may be used by another shaping method, for example, it is used by a fusion method. You may work.

Although the rotation member 42 of the said embodiment has a gear-shaped unevenness|corrugation in the outer periphery, it is not necessary to have a gear-shaped unevenness|corrugation in an outer periphery. Since the refrigerant does not flow inside the rotating member, in the vicinity of the rotating member, the glass ribbon is not strongly cooled and hard to harden. Therefore, even if there is no uneven|corrugated shape of a gear, a rotating member is easy to press a glass ribbon, and the contraction of the width direction of a glass ribbon can be suppressed.

6 is a cross-sectional view showing a rotating member according to a modification. Fig. 7 is a view showing the dimensions of the convex shape of the rotating member of Fig. 6; Fig. 8 is a view showing the dimensions of the convex shape of the rotating member of Fig. 6;

The rotating member 242 shown in Fig. 6 is used in place of the rotating member 42 shown in Fig. 3 or the rotating member 142 shown in Fig. 4. The outer circumferential surface of the rotating member 242 has a convex curved shape in a radially outward direction over the entire circumference, and the central portion in the axial direction protrudes radially outwardly from both ends in the axial direction. The outer peripheral surface of the rotating member 242 has the same cross-sectional shape over the entire circumference. Since there is no unevenness in the shape of a gear, it is difficult to break, and molding and processing costs are reduced.

For example, as shown in FIG. 7, in consideration of the gripping force with the glass ribbon 14, the radius of curvature Ra of the convex curve is preferably R1 to R100 mm, and more preferably R3 to R50 mm. And R5 to R30 mm are more preferable, and R10 to R20 mm are particularly preferred. Moreover, in the curvature of the convex, as shown in, for example, Fig. 8, the radius of curvature Rb of the central portion in the axial direction and the radius of curvature Rc of both ends of the axial direction may be a composite (R). At this time, both of the radius of curvature Rb and Rc are preferably R1 to R100 mm, more preferably R3 to R50 mm, more preferably R5 to R30 mm, and particularly preferably R10 to R20 mm. Moreover, in the curved image of the convex, a part may have a flat part, but it is preferable not to have a flat part because the grip force with the glass ribbon 14 is stable.

Considering the grip force with the glass ribbon 14, the radial width d of the rotating member 242 in the curved image of the convex shown in Fig. 7 is preferably 0.5 mm or more, more preferably 1 mm or more It is preferable, and 2 mm or more is more preferable. Similarly, 5 mm or less is preferable and, as for the width|variety (d) of the radial direction of the rotating member 242 in the said convex curved image, 4 mm or less is more preferable.

The radius r of the rotating member 242 shown in FIG. 7 is 100 mm or more in consideration of the prevention of contact between the flanges 46 and 146 and the glass ribbon 14 and the horizontality of the shaft members 44 and 144. Preferably, 150 mm or more is more preferable, 180 mm or more is more preferable, and 350 mm is considered when the positional adjustment of the rotating member 242 and the glass ribbon 14 or the fine adjustment of the rotational speed of the rotating member 242 is considered. The following is preferable, 300 mm or less is more preferable, and 270 mm or less is still more preferable.

In consideration of the grip force with the glass ribbon 14, the thickness w of the rotating member 242 is preferably 5 mm or more, more preferably 10 mm or more, even more preferably 15 mm or more, and 30 mm or more This is particularly preferable, and considering the improvement in flatness of the glass ribbon 14 or the prevention of enlargement of unnecessary grip width, 120 mm or less is preferable, 100 mm or less is more preferable, 80 mm or less is more preferable, and 60 mm or less Even more preferred, 40 mm or less is particularly preferred.

9 is a cross-sectional view showing a rotating member according to another modification. The rotating member 342 shown in Fig. 9 is used in place of the rotating member 42 shown in Fig. 3 or the rotating member 142 shown in Fig. 4. The cross-sectional shape of the outer circumferential surface of the rotating member 342 is flat, and the rotating member 342 has a boundary portion having a rounded cross-sectional shape between the outer circumferential surface and the side surface. The boundary portion is formed by chamfering or the like.

In the modified example shown in Fig. 6 or the modified example shown in Fig. 9, a plurality of protrusions with a height of 0.1 to 10 mm may be formed on the outer circumferential surface of the rotating member, or a plurality of grooves with a depth of 0.1 to 10 mm may be formed on the outer circumferential surface of the rotating member . Moreover, you may form both a protrusion and a groove in the outer peripheral surface of a rotating member. The height of the protrusion and the depth of the groove are measured using the outer peripheral surface of the rotating member as a reference surface. The height of the projection or the depth of the groove is smaller than the radius r shown in FIG. 7, the radius of curvature Ra shown in FIG. 7, and the radius of curvature Rb, Rc shown in FIG. 8.

This application claims priority based on Japanese Patent Application No. 2013-104380 filed with the Japan Patent Office on May 16, 2013, and uses the entire contents of Japanese Patent Application No. 2013-104380 in this application.

10: glass plate forming apparatus
40: support roll
42: rotating member
43: irregularities
44: shaft member
46: flange (extended member)
48: heat transfer member
50: pressing member
51: pressure member body
52: contact
54: first elastic body
60: insulating member
64: shim fit member
66: second elastic body
140: support roll
142: rotating member
144: shaft member
146: flange (extended member)
148: second insulating member
160: first heat insulating member
166: elastic body

Claims (13)

As a support roll supporting a glass ribbon on a strip,
A rotating member in contact with the glass ribbon,
A shaft member having a refrigerant passage therein and rotating together with the rotating member,
Has a charging member that is charged from the outer periphery of the shaft member,
The rotating member is formed of ceramics,
A first heat insulating member having a lower thermal conductivity than the rotating member is disposed between the outer circumference of the shaft member and the inner circumference of the rotating member inserted into the through hole of the rotating member,
A support roll in which a second heat insulating member having a lower thermal conductivity than the rotating member is disposed between the extending member and the rotating member. delete According to claim 1,
The support roll in which the contact surface with the said 1st heat insulation member in the said rotation member is tapered shape. According to claim 1,
The support roll in which the contact surface with the rotating member in the first heat insulating member is tapered. According to claim 1,
A support roll having a shim fitting member between an inner circumference of the first heat insulating member and an outer circumference of the shaft member. According to claim 1,
At least a portion of the rotating member in contact with the glass ribbon is formed of silicon nitride ceramics, a support roll. The method of claim 6,
The said silicon nitride ceramics is a sintered body, and the support roll whose aluminum (Al) content is 0.1 mass% or less, magnesium (Mg) content is 0.7 mass% or less, and titanium (Ti) content is 0.9 mass% or less. The method of claim 7,
The said silicon nitride ceramics support roll whose content of zirconium (Zr) is 3.5 mass% or less, and the content of yttrium (Y) is 0.5 mass% or more and 10 mass% or less. According to claim 1,
The support roll in which the outer circumferential surface of the rotating member is formed in a convex curved shape in a radially outward direction across the entire circumference. According to claim 1,
The rotating member has a gear-shaped irregularity on its outer periphery, a support roll. A method for forming a glass plate, comprising the step of supporting a strip-shaped glass ribbon using the support roll according to any one of claims 1 and 3 to 10. The glass plate forming apparatus which has the support roll in any one of Claims 1 and 3-10. The process of supporting the glass ribbon of a strip plate using the support roll in any one of Claims 1 and 3-10, and thereafter having the process of cooling and cutting the glass ribbon. , Glass plate manufacturing method.

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