KR20160008511A - Support roller, method for molding glass plate, method for manufacturing glass plate, and device for manufacturing glass plate - Google Patents

Abstract

[MEANS FOR SOLVING PROBLEMS] A supporting roll for supporting a glass ribbon on a strip plate, comprising: a rotating member in contact with the glass ribbon; a shaft member having a refrigerant passage therein and rotating together with the rotating member; Wherein a first heat insulating member having a thermal conductivity lower than that of the rotary member is disposed between the outer periphery of the shaft member inserted into the through hole of the rotary member and the inner periphery of the rotary member.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support roll, a method of forming a glass plate, a manufacturing apparatus of a glass plate, and a manufacturing method of a glass plate.

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

The forming method of the glass plate has a step of forming the molten glass into a glass ribbon of a strip shape. Glass ribbon thinner than the equilibrium thickness tends to decrease in the width direction. Therefore, in order to keep the thickness of the glass ribbon at a desired thickness, a support roll which applies tension in the width direction to the glass ribbon is used (see, for example, Patent Document 1). The support rolls are used in pairs and press on both side edges 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 at the tip end portion in contact with the glass ribbon, and the glass ribbon is released in a predetermined direction by rotating the rotating member. The glass ribbon is gradually cooled and hardened while moving in a predetermined direction.

Japanese Laid-Open Patent Publication No. 2011-225386

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

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a support roll capable of suppressing cracking of a rotating member made of ceramics.

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

A support roll for supporting a ribbon glass ribbon,

A rotating member in contact with the glass ribbon,

And a shaft member that has a refrigerant passage therein and rotates together with the rotary member,

The rotating member is formed of ceramics,

And a first heat insulating member having a thermal conductivity lower than that of the rotary member is disposed between the outer periphery of the shaft member inserted into the through hole of the rotary member and the inner periphery of the rotary member.

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

1 is a partial cross-sectional view showing a glass sheet forming apparatus according to a first embodiment of the present invention.
Fig. 2 is a plan view showing the lower structure of the glass sheet forming apparatus 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.
Fig. 5 is a graph showing the time variation of the wettability of the 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 1 showing a convex shape dimension of the rotating member of Fig. 6; Fig.
Fig. 8 is a view 2 showing a convex shape dimension of the rotating member of Fig. 6; Fig.
9 is a cross-sectional view showing a rotating member according to another modification.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and a description thereof will be omitted.

[First Embodiment]

1 is a partial cross-sectional view showing a glass sheet forming apparatus according to a first embodiment of the present invention. Fig. 2 is a plan view showing a lower structure of the glass sheet forming apparatus of Fig. 1; Fig.

The molding apparatus 10 forms the molten glass into a glass ribbon 14 in the form of a strip. The molding apparatus 10 includes a bath 20 accommodating a molten metal (for example, molten tin) 16, and a molten metal 16, which is continuously supplied on the molten metal 16, (X direction in FIG. 2) on the glass ribbon 14 to form a glass ribbon 14 on a strip plate. The glass ribbon 14 is cooled in the process of flowing in a predetermined direction (X direction in FIG. 2), then pulled up from the molten metal 16 by a lift-out roll, . The plate-like glass is taken out from the throat furnace and then cut into a predetermined shape by a cutting machine to obtain a glass plate as a product.

The molding apparatus 10 includes a bath 20 for accommodating the molten metal 16, a ceiling 22 formed above the bath 20, and a side wall 22 for blocking 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 into the gas supply path 32.

The gas supply path 32 supplies a reducing gas to the space above the molten metal 16 to prevent the molten metal 16 from being oxidized. The reducing gas includes, for example, 1 to 15% by volume of hydrogen gas and 85 to 99% by volume of nitrogen gas.

A plurality of heaters 34 are formed above the molten metal 16 and the glass ribbon 14 at intervals in the moving direction and the width direction of the glass ribbon 14. [ The output of the heater 34 is controlled so that the temperature of the glass ribbon 14 decreases from the upstream side toward the downstream side. 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 molding apparatus 10 has a support roll 40 which is used for suppressing shrinkage in the width direction of the glass ribbon 14 in the form of a strip. The support rolls 40 are used in pairs and press both side edges 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 rotary member 42 at the front end portion which contacts the glass ribbon 14 and the rotary member 42 is rotated to discharge the glass ribbon 14 in a predetermined direction. The glass ribbon 14 is gradually cooled and hardened while moving in a predetermined direction.

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

1, the rotating member 42 is provided on the outer periphery of the gear wheel-like projections 43 in contact with the glass ribbon 14, for example, as shown in Fig. 1, in order to suppress the slip of the glass ribbon 14 do. The shape of the convex portion of the gear-wheel concave and convex portion 43 is not particularly limited. However, for example, as shown in Fig. 3, the shape of the convex portion of the gear wheel concave and convex portion 43 may be formed to have a thin shape (for example, square abstract). As shown in Fig. 1, the gear wheel-shaped concave and convex portions 43 are formed in a row in the thickness direction (Y direction in Fig. 1) of the outer periphery of the rotary member 42, but may be formed in plural rows.

The rotary member 42 does not have a refrigerant passage therein. Since the shaft member 44 inserted into the through hole of the rotary member 42 is a member different from the rotary member 42, the refrigerant passage 45 formed in the shaft member 44 is connected to the rotary member 42, Which is formed on the outside of the refrigerant passage.

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

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

In the case of alkali-free glass, at least the portion of the rotary member 42 that contacts the glass ribbon 14 may be silicon nitride ceramics, and the entire rotary 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 a normal pressure sintering method, a pressure sintering method (including hot press sintering and gas pressure sintering), and the like. As sintering aids include, for example, alumina (Al ₂ O _3), magnesia (MgO), titania (TiO _2), zirconia (ZrO _2), and at least one selected from yttria (Y ₂ O ₃₎ is Is used.

The silicon nitride ceramics preferably has a content of aluminum (Al) of 0.1 mass% or less, preferably 1 mass% or less, a content of magnesium (Mg) of 0.7 mass% or less, preferably 0.7 mass% or less, The content may be 0.9 mass% or less, preferably 0.9 mass% or less. When the Al content, the Mg content, and the Ti content are in the above ranges, 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, . The Al content, Mg content and Ti content may each be 0 mass%.

The silicon nitride ceramics has a content of zirconium (Zr) of 3.5 mass% or less, preferably 3.5 mass% or less, a content of yttrium (Y) of 0.5 mass% or more, preferably 0.5 mass% or more, Preferably less than 10% by mass. Zr and Y are components that are less likely to be mutually diffused with the glass ribbon 14 as compared with Al, Mg, and Ti, and therefore may be contained in the above range. By being contained in the above-mentioned range, sintering of the silicon nitride powder can be promoted. Zr may be an optional component, and the Zr content may be 0 mass%.

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

The glass plate, which is a product, is not particularly limited and may be, for example, a flat panel display (FPD) such as a liquid crystal display (LCD), a plasma display (PDP), or an organic EL display. In recent years, the thinning of FPD has been progressing, and the thinning of the glass plate for FPD is progressing. In particular, in the case of a glass substrate 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, particularly preferably 0.1 mm or less is desired. As a result, the thickness of the glass ribbon 14 becomes thinner, the shrinking force in the width direction of the glass ribbon 14 becomes strong, and the forming temperature of the glass ribbon 14 becomes high. The support roll 40 of the present embodiment is provided between the outer periphery of the shaft member 44 inserted into the through hole of the rotation member 42 and the inner periphery of the rotation member 42, It is possible to suppress cracking of the rotary member 42 and is suitable for forming a glass plate for an FPD.

The kind of the glass plate as the product is not particularly limited. The composition of the glass plate is, for example, expressed in mass% based on the oxide, and includes 50 to 75% of SiO ₂ , 0.1 to 24% of Al ₂ O ₃ , 0 to 12% of B ₂ O ₃ , 0 to 10 , 0 to 14.5% of CaO, 0 to 24% of SrO, 0 to 13.5% of BaO, 0 to 20% of Na ₂ O, 0 to 20% of K ₂ O, 0 to 5% of ZrO ₂ , + CaO + SrO + BaO: 5 to 29.5%, and 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 containing no alkali metal oxide (Na ₂ O, K ₂ O, Li ₂ O, etc.). In the alkali-free glass, the total content of the alkali metal oxide may be 0.1% by mass or less.

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

The alkali-free glass preferably contains 58 to 66% of SiO ₂ , 15 to 22% of Al ₂ O _{3, and} 15 to 22% of B ₂ O ₃ : SiO ₂ in terms of% by mass based on the oxide, 5 to 12%, MgO: 0 to 8%, CaO: 0 to 9%, SrO: 3 to 12.5%, BaO: 0 to 2% and MgO + CaO + SrO + BaO: 9 to 18%.

In order to obtain a particularly high strain point, the alkali-free glass preferably contains 54 to 73% SiO ₂ , 10.5 to 22.5% Al ₂ O ₃ , B ₂ O ₃ : 0% , CaO: 0 to 9%, SrO: 0 to 16%, BaO: 0 to 2.5%, MgO + CaO + SrO + BaO: 8 to 26%.

The shaft member 44 is connected to a driving device 36 which passes through the side wall 24 and is arranged outside the side wall 24 as shown in Fig. The drive unit 36 is constituted by a motor, a speed reducer, and the like, and rotates the shaft member 44 about the center line of the shaft member 44. The shaft member 44 is inserted into the through hole formed at the center of the rotary member 42 and rotates together with the rotary member 42.

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

The flange 46 may be integrally formed with the shaft member 44. The flange 46 is projected in the radial direction of the rotary member 42 from the outer periphery of the shaft member 44 in the middle of the shaft member 44. A branch path 47 that branches off from the refrigerant flow path 45 of the shaft member 44 is formed on the inner periphery of the flange 46 and the branch path 47 extends to the vicinity of the outer periphery of the flange 46. The flange 46 is cooled by the refrigerant passing through the branch passage 47.

The heat transfer member 48 is formed, for example, in a ring shape. 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 the positioning groove 49 formed on the side of the flange 46 on the side of the rotary member 42. [

The heat conductive member 48 is formed between the flange 46 and the rotary member 42 and has a thermal conductivity higher than that of the rotary member 42 so that the heat of the rotary member 42, (46). The outer circumference of the rotary member 42 is maintained at a temperature at which the glass ribbon 14 does not stick to the outer periphery thereof, and the rotational torque can be reduced.

Here, the thermal conductivity of the heat transfer member 48 and the thermal conductivity of the rotary member 42 are measured at the temperature at which the support roll 40 is used. At the operating temperature of the support roll 40, the heat conductivity of the heat transfer member 48 is preferably 30 to 200 W / (m 占 폚).

The flange 46 cools the electrothermal heating member 48 and the electrothermal heating member 48 cools the rotating member 42 from the side so that the rotating member 42 The temperature gradient in the radial direction of the rotating member 42 becomes gentle and breakage due to thermal stress of the rotating member 42 can be suppressed.

The heat conductive member 48 may have a higher thermal conductivity than the rotary member 42, and may be made of, for example, metal or carbon. The metal or carbon is softer than the ceramics, and the heat transfer member 48 and the rotary member 42 are easy to come into close contact with each other. Therefore, the contact heat resistance is low and the heat transfer efficiency is good. From the viewpoint of heat resistance, carbon is particularly preferable.

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 rotary member 42 against the heat conductive member 48 to lower the contact thermal resistance between the heat conductive member 48 and the rotary member 42. [ The pressing member 50 is disposed on the side opposite to the heat transfer member 48 with respect to the rotary member 42 as a reference.

The pressing member 50 is constituted by, for example, a pressing member main body 51 and a contact portion 52. The pressing member main body 51 is formed of, for example, metal, and the shaft member 44 is inserted into the through hole formed at the central portion of the pressing member main body 51. The contact portion 52 may be formed in the same ring shape as 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 rotary member 42 Press intensively. The contact portion 52 is formed of metal or carbon. From the viewpoint of heat resistance, carbon is particularly preferable. The contact portion 52 is positioned by the positioning groove 53 formed on the side of the rotation member 42 side of the pressing member main body 51. When the contact portion 52 is formed of the same material as the pressing member main body 51, the contact portion 52 and the pressing member main body 51 may be integrally formed.

The first elastic body 54 elastically supports the pressing member 50 which can be freely displaced in the axial direction of the shaft member 44 with the rotating member 42 facing. The first elastic body 54 is formed of, for example, a disc spring, and the shaft member 44 is inserted into the through hole formed in the first elastic body 54. The shaft member 44 has a screw shaft portion 44a and a state in which the first elastic body 54 is reduced between the first nut 58 screwed to the screw shaft portion 44a and the rotary member 42 Respectively. The rotary member 42 is always pressed against the heat conductive member 48 by the pressing member 50 when a dimensional change occurs due to a temperature change or the like.

Further, the first elastic body 54 of the present embodiment is constituted by a disc spring, but may be constituted by a coil spring, and the structure of the first elastic body 54 is not particularly limited. In this case, the first nut 58 is pushed by the first nut 58 and the pressing member 50 is pressed against the rotary member 42 And presses the heat transfer member (48).

The heat insulating member 60 is formed, for example, normally. The heat insulating member 60 may be divided into a plurality of divided bodies (for example, two semi-divided bodies) in the circumferential direction in view of workability and cost.

The heat insulating member 60 is disposed between the inner periphery of the rotary member 42 and the outer periphery of the shaft member 44 and has a thermal conductivity lower than that of the rotary member 42, 44). The temperature gradient in the radial direction of the rotating member 42 becomes more gentle and breakage due to the 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. With respect to 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 占 폚).

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

The outer circumferential surface of the heat insulating member 60 is a contact surface that contacts the inner circumferential surface of the rotary member 42 and has a tapered shape whose diameter decreases toward the flange 46 along the center line of the rotary member 42. [ Similarly, the inner circumferential surface of the rotary member 42 is a contact surface that contacts the outer circumferential surface of the heat insulating member 60, and has a tapered shape whose diameter decreases toward the flange 46 along the center line of the rotary member 42. [ If the contact surfaces of at least one of the heat insulating member 60 and the rotary member 42 that are in contact with each other are tapered, the sticking between the heat insulating member 60 and the rotary member 42 can be reduced. The taper direction may be a reverse direction, and each contact surface may have a tapered shape in which the diameter increases toward the flange 46 along the center line of the rotary member 42. [

The core fitting member 64 aligns the center line of the heat insulating member 60 with the center line of the shaft member 44 and is formed for example as usual and is formed by the inner periphery of the heat insulating member 60 and the outer periphery of the shaft member 44 Respectively. The core fitting member 64 may be formed of metal in the same manner as the shaft member 44. The clearance between the core fitting member 64 and the shaft member 44 can be set to be narrow so that the core fitting member 64 and the shaft member 44 can be made to have a small clearance, Can be reduced.

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

The outer circumferential surface of the core fitting member 64 is a tapered surface that comes into contact with the inner circumferential surface of the heat insulating member 60 and has a smaller diameter toward the flange 46 along the center line of the rotary member 42. [ Similarly, the inner circumferential surface of the heat insulating member 60 is in contact with the outer circumferential surface of the core fitting member 64, and has a taper shape having a smaller diameter toward the flange 46 along the center line of the rotary member 42. [ Adhesion of the core fitting member 64 and the heat insulating member 60 can be reduced if the contact surface of at least one of the core fitting member 64 and the heat insulating member 60 which are in contact with each other is tapered. The taper direction may be a reverse direction, and each contact surface may have a tapered shape in which the diameter increases toward the flange 46 along the center line of the rotary member 42. [

Although the centering member 64 is disposed between the inner periphery of the heat insulating member 60 and the outer periphery of the shaft member 44 in the present embodiment, There may be a slight clearance between the inner periphery of the shaft member 44 and the outer periphery of the shaft member 44. [

The second elastic body 66 is provided with a heat insulating member 60 which can be freely displaced in the axial direction of the shaft member 44 via a fitting member 64 which can be freely displaced in the axial direction of the shaft member 44 ) Toward the flange (46). The second elastic body 66 is constituted by, for example, a disc spring, and the shaft member 44 is inserted into the through hole formed in the second elastic body 66. The second elastic body 66 is arranged between the second nut 68 screwed to the screw shaft portion 44a of the shaft member 44 and the key fitting member 64 in a state in which the second elastic body 66 is smaller than the natural state. It is possible to prevent the core fitting member 64 from separating from the heat insulating member 60 and to prevent the thermal insulating member 60 and the rotary member 42 from being separated from each other when a dimensional change occurs due to a temperature change or the like .

Further, the second elastic body 66 of the present embodiment is constituted by a disc spring, but may be constituted by a coil spring, and the configuration of the second elastic body 66 is not particularly limited. The second elastic body 66 comes into contact with the heat insulating member 60 and elastically supports the heat insulating member 60 with the flange 46 facing. In this case, by tightening the second nut 68, the core fitting member 64 and the heat insulating member 60 come into close contact with each other, and the heat insulating member 60 and the rotary member 42 are in close contact with each other.

The support roll 40 of the present embodiment is designed such that the glass ribbon 14 has a viscosity in the range of 10 ^4.5 to 10 ^7.5 dPa · s in the molding range of the molding apparatus 10 Region). ≪ / RTI > In the case of alkali-free glass, the glass ribbon 14 has a viscosity range of 10 ^4.5 to 10 ^7.5 dPa · s, and the glass ribbon 14 corresponds to a temperature range of 946 to 1200 ° C.

Further, 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 rotary member 42 between the flange 46 and the rotary member 42. [ On the other hand, in the support roll of the present embodiment, between the flange and the rotary member, a heat insulating member having a thermal conductivity lower than that of the rotary member is provided. The support roll of the present embodiment tends to become hot at a higher temperature than the support roll of the first embodiment and is liable to stick to the glass ribbon 14. [ Therefore, in the molding apparatus 10, the support roll of the present embodiment has a low temperature region (the glass ribbon 14 in the downstream side of the support roll of the first embodiment) having a viscosity range of more than 10 ^7.5 to 10 ^7.65 dPa · s Area). In the case of alkali-free glass, the range of viscosity in which the glass ribbon 14 is in a range of more than 10 ^7.5 to 10 ^7.65 dPa · s corresponds to a temperature range of 937 ° C to 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 rotary member 142, a shaft member 144, a flange 146 as a projecting member, a second heat insulating member 148, a first heat insulating member 160, a core fitting member 164, An elastic body 166 and the like.

The rotating member 142 is configured in the same manner as the rotating member 42 shown in Fig. 3 or the like.

The shaft member 144 is constructed in the same manner as the shaft member 44 shown in Fig. 3 and is inserted into a through hole formed at the center of the rotary member 142 and rotated together with the rotary member 142. [ The shaft member 144 has therein a refrigerant passage 145 through which a refrigerant such as water passes.

The flange 146 may be formed integrally with the shaft member 144. The flange 146 is projected in the radial direction of the rotary member 142 from the outer periphery of the shaft member 144 in the middle of the shaft member 144. A branch passage 147 that branches off from the refrigerant passage 145 of the shaft member 144 is formed on the inner periphery of the flange 146 and the branch passage 147 extends to the vicinity of the outer periphery of the flange 146. The flange 146 is cooled by the refrigerant passing through the branch passage 147.

The second heat insulating member 148 is formed, for example, in a ring shape. 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 the positioning groove 149 formed on the side of the flange 146 on the side of the rotary member 142.

The second heat insulating member 148 is formed between the rotating member 142 and the flange 146 and has a thermal conductivity lower than that of the rotating member 142 and has a thermal conductivity higher than that of the rotating member 142 Thereby suppressing escape to the flange 146. It is difficult for the rotating member 142 to be cooled from the side and the glass ribbon 14 is difficult to be cooled by contact with the rotating member 142 and hard to harden. This makes it easier for the rotating member 142 to press the glass ribbon 14 and suppress the shrinkage of the glass ribbon 14 in the width direction. This is particularly effective for a portion of the glass ribbon 14 having a low temperature.

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. With respect to 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 占 폚).

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

The second heat insulating member 148 and the rotary member 142 need not be in close contact with each other and the pressing member 50 and the first elastic member 54 of the first embodiment may be omitted.

3 and is disposed between the inner periphery of the rotary member 142 and the outer periphery of the shaft member 144 and the rotary member 142 is disposed between the inner periphery of the rotary member 142 and the outer periphery of the shaft member 144. The first heat insulating member 160, So that the heat of the rotary member 142 can be prevented from escaping to the shaft member 144. The temperature gradient in the radial direction of the rotary member 142 becomes more gentle and breakage due to the thermal stress of the rotary member 142 can be suppressed.

The core fitting member 164 is constructed in the same manner as the core fitting member 64 shown in Fig. 3 or the like and is designed to align the center line of the shaft member 144 with the center line of the first heat insulating member 160. For example, Formed between the inner periphery of the first heat insulating member (160) and the outer periphery of the shaft member (144).

In this embodiment, the fitting member 164 is disposed between the inner periphery of the first heat insulating member 160 and the outer periphery of the shaft member 144, but the fitting member 164 may not be provided, There may be a slight clearance between the inner periphery of the member 160 and the outer periphery of the shaft member 144. [

The elastic body 166 is constructed in the same manner as the second elastic body 66 shown in Fig. 3 and is constituted by a shaft member 144 (not shown) via a core fitting member 164 which is freely displaceable in the axial direction of the shaft member 144 The first heat insulating member 160, which can be freely displaced in the axial direction of the flange 146, is elastically supported. The elastic member 166 is formed of, for example, a flat spring, and the shaft member 144 is inserted into the through-hole formed in the elastic member 166. The elastic body 166 is arranged between the nut 168 screwed to the screw shaft portion 144a of the shaft member 144 and the key fitting member 164 in a state in which the elastic body 166 is smaller than the natural state.

The elastic body 166 of the present embodiment is constituted by a disc spring, but may be constituted by a coil spring. The configuration of the elastic body 166 is not particularly limited. The elastic member 166 comes into contact with the first heat insulating member 160 and elastically supports the first heat insulating member 160 with the flange 146 facing. In this case, by tightening the nut 168, the core fitting member 164 and the first heat insulating member 160 come into close contact with each other and the first heat insulating member 160 and the rotating member (not shown) 142 are in close contact with each other.

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 examined.

The test pieces and the test plates for evaluation were prepared by processing sintered bodies of silicon nitride (Si ₃ N ₄ ) vapors different from each other.

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

The wettability of the sintered body to the molten glass was measured by a high temperature wettability tester (WET1200, manufactured by ULVAC KK). Concretely, each glass piece of an alkali-free glass (AN100, manufactured by Asahi Glass Co., Ltd.) was placed on a test plate having a thickness of 1 mm, the temperature was elevated to 1150 캜 for 10 minutes in a nitrogen atmosphere, For 10 minutes to produce molten glass, and then the temperature was dropped from 1150 占 폚 to 1050 占 폚 for 90 seconds and maintained at 1050 占 폚 to measure the contact angle of the droplet. The measurement was carried out at the point of dropping to 1050 占 폚, and 2 hours, 4 hours, 6 hours, and 8 hours after that point. The larger the contact angle means that the molten glass does not wet well on the sintered body, it indicates that the reactivity between the molten glass and the sintered body is low. Further, the smaller the change in the contact angle with time, the easier the wetting is likely to last.

The evaluation results are shown in Table 1 and Fig. 5, the vertical axis represents the contact angle (DEG), and the horizontal axis represents elapsed time (h: hours). Further, 10000 mass ppm is 1 mass%.

As 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 0.7 mass% or less, the Ti content is 0.9 mass% Preferably less than 0.9 mass%, a Zr content of 3.5 mass% or less, preferably less than 3.5 mass%, a Y content of 0.5 mass% or more and 10 mass% or less, preferably 0.5 mass% or less and 10 mass% or less , The time change of the contact angle is small, and the contact angle after 8 hours is large, so that good durability can be obtained.

While the embodiments of the support roll, the method of manufacturing the glass plate, and the apparatus of manufacturing the glass plate have been described above, the present invention is not limited to the above-described embodiments. The present invention can be modified or improved within the scope of the claims.

For example, the support roll 40 of the above embodiment is used in the float process for molding the glass ribbon 14 on the molten metal 16, but may be used in other molding processes, for example in the fusion process .

The rotary member 42 of the above-described embodiment has a gear wheel concavity on the outer periphery, but may not have a gear wheel concavity on the outer circumference. Since the refrigerant does not flow inside the rotary member, the glass ribbon is not strongly cooled in the vicinity of the rotary member, and hardly hardened. Therefore, even if there is no unevenness on the toothed wheel, the rotating member can easily press the glass ribbon, and shrinkage in the width direction of the glass ribbon can be suppressed.

6 is a cross-sectional view showing a rotating member according to a modification. Fig. 7 is a view 1 showing a convex shape dimension of the rotating member of Fig. 6; Fig. 8 is a view 2 showing a convex shape dimension 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. The outer circumferential surface of the rotary member 242 has a cross-sectional shape that is convex outward in the radial direction over its entire circumference, and the axially central portion protrudes radially outwardly from both axial end portions. The outer circumferential surface of the rotary member 242 has the same cross-sectional shape over the entire circumference. Since there are no concavities and convexities on the cog wheels, it is hard to break and molding and processing costs are reduced.

For example, as shown in Fig. 7, the radius of curvature (Ra) of the convex curved shape is preferably R1 to R100 mm, more preferably R3 to R50 mm in view of the gripping force with the glass ribbon 14 More preferably R5 to R30 mm, and particularly preferably R10 to R20 mm. 8, the curvature radius Rb of the axially central portion and the curvature radius Rc of the axially opposite end portions may be complex (R), for example, as shown in Fig. At this time, all of the curvature radii Rb and Rc are preferably R1 to R100 mm, more preferably R3 to R50 mm, further preferably R5 to R30 mm, and particularly preferably R10 to R20 mm. Further, in the curved convex shape, a part may have a flat part, but it is preferable that it does not have a flat part because the grip strength with the glass ribbon 14 is stable.

Considering the gripping force with the glass ribbon 14, the width d in the radial direction of the rotary member 242 in the convex curved shape shown in Fig. 7 is preferably 0.5 mm or more, more preferably 1 mm or more More preferably 2 mm or more. Similarly, the width d in the radial direction of the rotary member 242 in the convex curved shape is preferably 5 mm or less, more preferably 4 mm or less.

The radius r of the rotary member 242 shown in Fig. 7 is preferably 100 mm or more in consideration of the prevention of contact between the flanges 46, 146 and the glass ribbon 14 and the horizontality of the shaft members 44, 144 More preferably not less than 180 mm and more preferably not less than 350 mm in consideration of the adjustment of the position of the rotary member 242 and the glass ribbon 14 and the fine adjustment of the rotational speed of the rotary member 242, More preferably not more than 300 mm, and even more preferably not more than 270 mm.

The thickness w of the rotating member 242 is preferably 5 mm or more, more preferably 10 mm or more, more preferably 15 mm or more, and more preferably 30 mm or more in consideration of the gripping force with the glass ribbon 14 Is preferably not more than 120 mm, more preferably not more than 100 mm, further preferably not more than 80 mm, more preferably not more than 60 mm, in consideration of the flatness of the glass ribbon 14 and the prevention of unnecessary increase in grip width And more preferably 40 mm or less.

9 is a cross-sectional view showing a rotating member according to another modified example. The rotary member 342 shown in Fig. 9 is used in place of the rotary member 42 shown in Fig. 3 or the rotary member 142 shown in Fig. The cross-sectional shape of the outer peripheral surface of the rotary member 342 is flat, and the rotary member 342 has a boundary portion having a round cross-sectional shape between the outer peripheral surface and the side surface. The boundary portion is formed by a chamfer or the like.

In the modified example shown in Fig. 6 or the modified example shown in Fig. 9, a plurality of protrusions having a height of 0.1 to 10 mm may be formed on the outer circumferential surface of the rotary member, or a plurality of grooves having a depth of 0.1 to 10 mm may be formed on the outer circumferential surface of the rotary member . Both the projection and the groove may be formed on the outer peripheral surface of the rotary member. The height of the projection and the depth of the groove are measured with the outer peripheral surface of the rotary member serving as a reference surface. The height of the projection and the depth of the groove are 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.

The present application claims priority based on Japanese Patent Application No. 2013-104380 filed on May 16, 2013, and Japanese Patent Application No. 2013-104380 is incorporated herein by reference in its entirety.

10: Glass plate forming device
40: support roll
42: rotating member
43: unevenness
44:
46: flange (projecting member)
48:
50: pressing member
51: pressing member main body
52:
54: first elastic body
60:
64:
66: Second elastic body
140: Support roll
142: Rotating member
144:
146: Flange (projecting member)
148: Secondary thermal insulating member
160: first insulating member
166: elastomer

Claims (13)

A support roll for supporting a ribbon glass ribbon,
A rotating member in contact with the glass ribbon,
And a shaft member that has a refrigerant passage therein and rotates together with the rotary member,
The rotating member is formed of ceramics,
Wherein a first heat insulating member having a thermal conductivity lower than that of the rotary member is disposed between an outer periphery of the shaft member inserted into the through hole of the rotary member and an inner periphery of the rotary member. The method according to claim 1,
A projecting member projecting from the outer periphery of the shaft member;
And a second heat insulating member disposed between the projecting member and the rotary member and having a thermal conductivity lower than that of the rotary member. 3. The method according to claim 1 or 2,
And a contact surface of the rotary member with the first heat insulating member is tapered. 4. The method according to any one of claims 1 to 3,
And the contact surface of the first heat insulating member with the rotating member is tapered. 5. The method according to any one of claims 1 to 4,
And a centering member between the inner periphery of the first heat insulating member and the outer periphery of the shaft member. 6. The method according to any one of claims 1 to 5,
Wherein at least a portion of the rotating member which is in contact with the glass ribbon is formed of silicon nitride ceramics. The method according to claim 6,
Wherein the silicon nitride ceramics is a sintered body having a content of aluminum (Al) of 0.1 mass% or less, a content of magnesium (Mg) of 0.7 mass% or less, and a content of titanium (Ti) of 0.9 mass% or less. 8. The method of claim 7,
Wherein the silicon nitride ceramics has a content of zirconium (Zr) of 3.5 mass% or less and a content of yttrium (Y) of 0.5 mass% or more and 10 mass% or less. 9. The method according to any one of claims 1 to 8,
Wherein the outer circumferential surface of the rotating member is formed in a curved shape having a convex shape in the radial direction outward over its entire circumference. 9. The method according to any one of claims 1 to 8,
Wherein the rotating member has a stepped surface on the outer periphery thereof. A method of forming a glass plate, comprising the step of supporting a glass ribbon on a strip plate by using the support roll according to any one of claims 1 to 10. A forming apparatus for a glass plate having the support roll according to any one of claims 1 to 10. A method for manufacturing a glass plate having a step of supporting a glass ribbon on a strip plate by using the support roll according to any one of claims 1 to 10 and thereafter a step of cooling and cutting the glass ribbon Way.

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