KR20160013810A - Method and apparatus for manufacturing glass - Google Patents

Abstract

The present invention is to provide a manufacturing method of glasses, which suppresses slipping of glass ribbon on a plurality of rolls when conveying the glass ribbon using the rolls. The manufacturing method of glasses of the present invention comprises a conveying process, which arranges glass ribbon formed in a float bath on the rolls and conveys the glass ribbon using the rolls. At least one roll selected among the rolls is connected with a torque applying device which applies torque to the rolls. During the conveying process, the torque applying device controls the torque applied to the roll connected with the torque applying device based on the speed of the glass ribbon.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a glass manufacturing method,

The present invention relates to a glass manufacturing method and an apparatus for manufacturing glass.

The glass (glass substrate) can be produced, for example, by cutting a glass ribbon to an arbitrary size. As a method for producing glass ribbon, for example, a float method has been used conventionally.

In the float method, the molten glass is first poured onto molten tin in the float bath, and the molten glass spreads on the molten tin, so that the molten glass reaches the equilibrium thickness. When the glass is pulled in the direction of the layer from the downstream side of the float bath, the glass is stretched and advances in the downstream direction of the float bath to form a strip-shaped glass ribbon. The glass ribbon taken out from the float bath is cooled by being conveyed by a plurality of rolls rotationally driven in the layer at the same speed preset by the speed controller.

However, when the glass ribbon is transported by a plurality of rolls after the glass ribbon is taken out from the float bath, the glass ribbon slips on the roll, and periodic scratches occur in the flow direction of the glass ribbon.

Therefore, various studies have been made on a method for preventing the glass ribbon from sliding on the roll and causing periodic scratches in the flow direction of the glass ribbon.

For example, in Patent Document 1, the glass ribbon is thermally shrunk during transportation of the glass ribbon, and a difference occurs in the conveying speed of the glass ribbon depending on the conveying position. Therefore, the conveying speed of the glass ribbon is changed with respect to the peripheral speed of the roller, And a problem that a glass ribbon is scratched due to sliding on the roller is disclosed. Specifically, a roller of a roller conveyor is provided on a rotary shaft of a roller conveyor through a bearing, and the driving force from the rotary shaft is transmitted to the roller by the rotation frictional resistance generated in the bearing to convey the conveyed object, When the conveying speed of the conveyed object is changed with respect to the conveying direction of the conveyed object, the driving force of the rotating shaft is absorbed by the bearing and the driving force is not transmitted to the roller.

Japanese Patent Application Laid-Open No. 11-236114

In recent years, however, higher quality has been required for the glass to be produced. Further, a glass having a thinner plate thickness is also required.

In order to meet such a demand, a countermeasure such as changing the material of the conveying roll or the composition of the glass to be produced is performed, but with the change of the manufacturing conditions, the glass ribbon becomes more slippery than on the roll. For this reason, for example, in the conveying method of the conveyed object disclosed in Patent Document 1, it is impossible to sufficiently suppress the occurrence of slippage.

Accordingly, in view of the problems of the prior art, there is provided, in one aspect of the present invention, a glass manufacturing method and a glass manufacturing apparatus wherein glass ribbon is prevented from sliding on a roll when a glass ribbon is transported by a plurality of rolls .

According to an aspect of the present invention for solving the above problems, there is provided a glass manufacturing method comprising a transporting step in which a glass ribbon formed by a float bath is disposed above a plurality of rolls and the glass ribbon is transported by the plurality of rolls / RTI >

A torque applying means for applying a torque to the roll is connected to at least one of the plurality of rolls,

In the carrying step,

The torque application means controls the torque applied to the connected roll by the torque application means based on the speed of the glass ribbon.

According to another aspect of the present invention, there is provided a float bath,

A plurality of rolls for conveying the glass ribbon formed in the float bath,

A torque application means for applying a torque to the roll is connected to at least one of the plurality of rolls,

And control means for controlling the torque applied by the torque application means to the roll to which the torque applying means is connected based on the speed of the glass ribbon.

According to one aspect of the present invention, it is possible to provide a glass manufacturing method and a glass manufacturing apparatus in which glass ribbon is prevented from sliding on a roll when a glass ribbon is transported by a plurality of rolls.

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
Fig. 2 is an explanatory diagram of a mechanism in which a glass ribbon slides on a roll carrying glass ribbon; Fig.
3 is a control example when a torque is applied to a roll by a torque applying means in a glass manufacturing method according to an embodiment of the present invention.
4 is an explanatory diagram of a configuration example in which molten tin removing means is disposed in the glass manufacturing method according to the embodiment of the present invention.
Fig. 5 is an explanatory diagram of a configuration example of a roll to which a torque application means is connected in the glass manufacturing apparatus according to the embodiment of the present invention; Fig.
6 is an explanatory diagram of a configuration of a roll to which a torque application means is connected in Embodiment 1 of the present invention;

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments, and various modifications and substitutions may be made to the embodiments without departing from the scope of the present invention.

(Production method of glass)

The glass manufacturing method of the present embodiment may include a transporting step of disposing a glass ribbon formed by a float bath above a plurality of rolls and transporting the glass ribbon by a plurality of rolls. In the conveying step, a torque applying means for applying a torque to the roll may be connected to at least one of the plurality of rolls. And, in the conveying step, the torque applying means can control the torque applied to the roll to which the torque applying means is connected, based on the speed of the glass ribbon.

Here, an outline of a manufacturing method of glass will be described with reference to Fig. 1 is an enlarged view of the vicinity of the float bath 11 of the glass manufacturing apparatus.

The molten tin 111 is filled in the float bath 11 and molten glass can be introduced onto the molten tin 111 from the left side of the drawing, not shown. When the molten glass is supplied onto the molten tin 111, the molten glass spreads on the molten tin 111 and reaches the equilibrium thickness in the process of moving toward the float bath outlet 112 on the right side in the figure. When the glass is pulled in the direction of the layer (slow cooling path) 12 from the float bath outlet 112 side, the glass is stretched and advances to the float bath outlet 112 side to become the glass ribbon 13 formed into a strip shape (Molding process).

The glass ribbon 13 taken out from the float bath 11 is disposed above the plurality of rolls 121 and 122 that are rotationally driven at the same speed preset by the speed controller in the layer 12, 121 and 122, respectively. In the conveying step, the glass ribbon 13 is conveyed in the layer 12 by the plurality of rolls 121, 122, whereby the cooling can be performed. The glass ribbon 13 formed on the float bath 11 is installed on the side of the float bath outlet 112 among the rolls used for transporting the glass ribbon 13 and is lifted from the float bath outlet 112 The conveying roll 122 is also called a lift-out roll. Although FIG. 1 shows an example in which one lift-out roll is disposed, it is not limited to this example, and a plurality of lift-out rolls may be disposed.

The glass ribbon cooled by the transporting step can be provided to a cutting step of cutting to an arbitrary size as required. Although the outline of the manufacturing method of glass has been described so far, the present invention is not limited to the above-described process, and an arbitrary process may be further added.

The glass ribbon 13 is taken out from the float bath 11 and then conveyed by the plurality of rolls 121 and 122 to carry the glass ribbon 13 as described above can do. In some cases, the glass ribbon 13 slides on the rolls 121 and 122 in the carrying process, causing scratches on the glass ribbon 13. [

Here, in the case where the glass ribbon is conveyed by the roll, when the maximum traction friction torque T1 _MAX at which the glass ribbon rotates the roll is larger than the torque T2 conveying the glass ribbon, according to the law of action reaction, A torque T1 of the same magnitude as the torque T2 is applied in the direction opposite to the torque T2 so that the roll can rotate at the same speed as that of the glass ribbon. Thus, it is considered that the glass ribbon can be prevented from sliding on the roll.

In addition, the torque T1 and the maximum traction torque is thereby T1 _MAX satisfy a relationship of T1≤T1 _MAX.

Further, the torque T1 at which the glass ribbon rotates the roll satisfies the following expression (1).

(Torque T1 in which the glass ribbon rotates the roll) = glass weight x friction resistance x roll diameter / 2 ... (Equation 1)

However, as described above, in recent years, a high quality glass ribbon is required, and in order to improve the quality, for example, a method of changing the material of the roll is adopted. However, as a result, for example, the frictional resistance of Equation 1 becomes small, T1 becomes small, T1 becomes smaller than T2, and slipping easily occurs.

In addition, since the glass ribbon needs to be thinned, the weight of the glass is getting smaller. As a result, T1 becomes smaller and T1 becomes smaller than T2, so that slippage easily occurs.

Therefore, the inventors of the present invention have studied a method of suppressing the glass ribbon from sliding on the roll in the conveying step.

First, an ideal state of the torque applied to the roll, in which the glass ribbon does not cause slippage on the roll when the glass ribbon is being conveyed, will be described with reference to Fig. 2A. 2 (A) shows a cross-sectional view on a plane perpendicular to the central axis of the roll 21 when the glass ribbon 22 is being conveyed by the roll 21, and the roll 21 The glass ribbon 22 is in contact with the contact point 23.

2 (A), the arrows in the roll 21 indicate the static friction torque A, the running resistance torque B, and the maximum traction friction torque C, respectively. The static friction torque A is a reaction force of the running resistance torque B, and the magnitude of the reaction force is equal to or smaller than the maximum static friction torque C.

2 (A), when the glass ribbon 22 is transported in the direction of the block arrow shown in the figure, that is, in the right direction in the drawing, the running resistance torque B is set to the left side And the static friction torque A, which is the reaction force thereof, is generated in the rightward direction. At this time, when the running resistance torque B is smaller than the maximum traction friction torque C, the static friction torque A becomes equal to the running resistance torque B, so that the both are balanced and the roll is in an apparently stopped state . That is, since the glass ribbon 22 is moving, the roll can rotate at the speed of the glass ribbon, and slippage can be suppressed.

On the other hand, a state in which slip is likely to occur will be described with reference to Fig. 2 (B). 2 (B) is a plan view showing the state in which the glass ribbon 22 is conveyed in the direction of the block arrow in the drawing by the roll 21 as in the case of Fig. 2 (A) And the roll 21 and the glass ribbon 22 are in contact with each other at the contact point 23. As shown in Fig.

As described above, recently, for example, the frictional resistance is reduced due to the change of the material of the roll, or the weight of the glass is decreased according to the thinning of the glass. Therefore, as shown in Fig. 2 (B), the maximum static friction torque C is reduced.

When the running resistance torque B is generated as shown in Fig. 2 (B), the static friction torque A is generated as the reaction force, but the size of the static friction torque A becomes equal to or less than the maximum static friction torque C. Therefore, as shown in FIG. 2 (B), the running resistance torque B becomes larger than the traction friction torque A, so that the two can not be balanced. Therefore, the roll can not be rotated and the speed of the glass ribbon and the peripheral speed The slippage has occurred.

Therefore, in the glass manufacturing method of the present embodiment, it is possible to connect torque applying means for applying torque to the rolls to one or more rolls selected from a plurality of rolls. Here, the torque applying means is means for applying a torque to the roll to which the torque applying means is connected, based on the velocity of the glass ribbon.

2 (B), torque is applied to the roll by the torque application means so that the running resistance torque B applied to the roll 21 becomes smaller than the apparent maximum static friction torque C, It is possible to correct that the balance of applied torque is largely broken. Thus, the peripheral speed difference between the glass ribbon and the roll at the contact point of the roll to which the glass ribbon and the torque application means are connected can be reduced, and slippage can be suppressed. Since occurrence of slippage can be suppressed, occurrence of scratches on the glass ribbon can be suppressed, and the yield of glass (glass substrate) as a product can be improved.

Further, the peripheral velocity of the roll means the velocity of the roll at the contact point of the glass ribbon and the roll to which the torque applying means is connected (hereinafter simply referred to as " contact point of glass and roll "

The torque application means controls the speed difference between the speed of the glass ribbon and the peripheral speed of the roll at the contact point between the glass ribbon and the roll based on the speed of the glass ribbon based on the speed of the glass ribbon, It is preferable to apply a torque to the roll so as to be within ± 1.0%. It is more preferable to apply a torque to the roll so that the speed difference between the speed of the glass ribbon and the peripheral speed of the roll at the contact point of the glass ribbon and the roll is within ± 0.5% , It is more preferable to apply a torque to the roll so as to be within ± 0.25%, and it is particularly preferable to apply a torque to the roll so as to be within ± 0.18%. The lower limit of the speed difference between the speed of the glass ribbon and the circumferential speed of the roll at the contact point between the glass ribbon and the roll is not particularly limited and is preferably small.

Further, as described above, the glass ribbon is conveyed by a plurality of rolls rotationally driven at the same speed preset by the speed controller in the layer. However, it is difficult to directly measure the velocity of the glass ribbon at a high temperature. Therefore, in general, the speed of the glass ribbon is indirectly obtained by the circumferential speed, assuming that the speed is the same as the circumferential speed of the roll set in advance by the speed controller in the layer in advance.

The speed of the glass ribbon may also be obtained by other methods. For example, the velocity of the glass ribbon measured by any velocity measuring means at a lower temperature point in the layer may be used. Also, when the velocity of the glass ribbon can be directly measured, the average value of the velocity of the glass ribbon in the measurement period may be used as a reference.

The configuration of the torque application means is not particularly limited as long as it is possible to apply a rotational torque in the circumferential direction of the roll to the roll, but for example, it may have a motor in which the magnitude of the applied torque is variable. For example, it is possible to control the magnitude of the torque applied to the roll by controlling the amount of current flowing through the motor by the control means.

The specific method (control method) for controlling the torque applied to the roll to which the torque applying means is connected based on the speed of the glass ribbon in the conveying step is not particularly limited and may be carried out by any method can do. Also, the control based on the velocity of the glass ribbon is not limited to the case where only the velocity of the glass ribbon is used as the control parameter. For example, when the control is performed in combination with other parameters, or when the glass ribbon speed is used as one of the parameters in the preliminary test or the like as described later, or when the glass ribbon speed is used as a parameter for evaluating the control result And the like.

As a specific method of controlling the torque applied to the roll, based on the speed of the glass ribbon in the conveying step, the torque applying unit may take the following form, for example. The following examples are illustrative of the control method and are not limited to these examples.

For example, in the conveying step, the peripheral speed of the roll set by the speed controller can be set to the speed of the glass ribbon as described above. And the torque application means controls the torque applied to the roll to which the torque applying means is connected based on the speed difference between the peripheral speed of the roll actually detected with respect to the roll to which the torque application means is connected and the speed of the glass ribbon can do.

Further, the torque applying means may perform a preliminary test in advance to determine the magnitude of the torque applied to the roll to which the torque applying means is connected. In this case, in the preliminary test, for example, the magnitude of the torque can be selected so that the speed difference between the speed of the glass ribbon and the peripheral speed of the roll actually detected with respect to the roll to which the torque applying means is connected falls within a predetermined range. In manufacturing the product, the torque of the size selected from the result of the preliminary test can be applied to the roll to which the torque applying means is connected by the torque applying means.

Further, when the circumferential speed of the roll is stable, the speed of the glass ribbon is detected in the conveying step, and the torque applying means controls the torque applied to the roll to which the torque applying means is connected by using the detected speed of the glass ribbon . At this time, the position at which the velocity of the glass ribbon is detected is not particularly limited. For example, it is preferable to detect the velocity of the glass ribbon in the vicinity of the roll to which the torque application means is connected, It is more preferable to detect it. However, since it is difficult to detect the velocity of the high-temperature glass ribbon as described above, when the glass ribbon is in a high-temperature region, it is difficult to detect the speed of the glass ribbon at a low temperature The speed of the measured glass ribbon can also be used. The peripheral speed of the roll to which the torque applying means is connected may also be detected and the torque applied by the torque applying means to the roll may be controlled by the detected speed of the glass ribbon and the detected peripheral speed of the roll.

Further, for example, the torque applied to the roll, such as the running resistance torque or the maximum static friction torque, is measured, and the occurrence of slippage is suppressed by controlling the magnitude of the torque applied to the roll by the torque applying means , The difference between the peripheral speed of the glass ribbon and the roll at the contact point of the glass ribbon and the roll can be set within a predetermined range.

Specifically, for example, the torque applied to the roll may be controlled by applying a torque to the roll by a torque applying means according to the magnitude of the torque applied to the measured roll, so that the torque applied to the roll is balanced. This is because, as described above, it is considered that a slip occurs when the balance of the torque applied to the roll is broken. The running resistance torque and the maximum traction friction torque to be used for the control may be values measured during actual operation. For example, the torque may be measured in advance in a preliminary test, As shown in Fig.

An example of control when a torque is applied to the roll by the torque applying means will be described with reference to Fig. Here, examples in which the magnitude of the running resistance torque and the maximum traction friction torque are measured in advance and controlled based on the measured values are shown.

3, the abscissa represents the time and the ordinate represents the torque. Then, the contact point 23 between the glass ribbon 22 and the roll 21 in FIG. 2 (A) is used as a reference point, and the torque applied in the counterclockwise direction in FIG. 2 (A) 3, the torque applied in the clockwise direction in Fig. 2 (A) is shown on the positive side, that is, above the zero in Fig. 3.

As shown in Fig. 3, a line 31 representing the running resistance torque is generated on the minus side in the figure. On the other hand, a torque having a magnitude equivalent to the running resistance torque on the plus side is applied to the roll as shown by the line 32 by the torque applying means.

At this time, the sum of the running resistance torque and the torque applied to the roll by the torque applying means is indicated by a line 33. [ In the control example shown in Fig. 3, the line 33 indicating the sum of the running resistance torque and the torque applied to the roll by the torque applying means is between the dotted line 341 and the dotted line 342 indicating the maximum static friction torque . As a result, the sum of the running resistance torque and the torque applied by the torque applying means can be balanced with the static friction torque, and slippage can be suppressed. Since the velocity of the glass ribbon and the circumferential velocity of the roll become substantially equal to each other by suppressing the occurrence of slippage, the velocity difference between them can be made within ± 1.0% with respect to the velocity of the glass ribbon.

In the control example shown in Fig. 3, the torque applied by the torque application means is made constant in size, but the present invention is not limited to this. The magnitude of the torque applied by the torque applying means may be changed in accordance with the change of the magnitude of the running resistance torque, for example.

As described with reference to Fig. 1, in the conveying step of the glass manufacturing method, a plurality of rolls can be used to convey the glass ribbon. The torque applying means described so far may be provided in at least one selected one of the plurality of rolls. The method of selecting the roll connecting the torque applying means is not particularly limited. For example, a roll which is likely to cause slippage can be selected, and the torque applying means can be connected to the selected one or plural rolls. Further, when connecting torque applying means to a plurality of rolls, torque applying means may be provided for each roll connecting the torque applying means.

In addition, a plurality of lift-out rolls may be provided as described above. In this case, for example, the torque-applying means may be connected to the selected one or a plurality of lift-out rolls, do.

In the method of manufacturing a glass ribbon of the present embodiment, for example, torque applying means may be provided and connected to one or a plurality of rolls used in the carrying step.

The size of the glass produced by the glass ribbon manufacturing method of the present embodiment is not particularly limited. However, as described above, the thickness of the glass has recently become thinner, and slippage is particularly likely to occur. According to the glass manufacturing method of the present embodiment, slippage can be easily suppressed. Thus, particularly when the thickness of the glass substrate to be manufactured and transported is thin, it exerts a high effect. Specifically, for example, the thickness of the glass produced by the glass manufacturing method of the present embodiment is preferably 1.0 mm or less, more preferably 0.5 mm or less. The lower limit of the thickness of the glass is not particularly limited, and it is only required that the thickness of the glass can be produced. For example, 1 mu m or more.

The molten tin removing means for removing molten tin from the surfaces of the rolls 121 and 122 as the auxiliary equipment for the rolls 121 and 122 is provided in the rolls 121 and 122 in the above- Can be installed.

The molten tin removing means may be arranged below the selected one or plurality of rolls so as to be in sliding contact with the selected roll. And the molten tin removing means is brought into sliding contact with the selected roll to remove molten tin adhering to the surface of the selected roll.

Here, FIG. 4 shows a configuration example in which molten tin removing means is disposed. 4 shows a sectional view on a plane perpendicular to the center axis of the roll 121 (122), and shows a state in which the glass ribbon 13 is conveyed in the right direction indicated by the block arrow in the figure .

As shown in Fig. 4, the molten tin removing means 41 can be disposed below the rolls 121 (122). And can be configured to be in sliding contact with the rolls 121 (122). The sliding contact refers to a state in which the molten tin removing means 41 is in contact with the roll 121 (122) so that the roll 121 (122) is rotatable.

Removal of molten tin from the roll 121 (122) is carried out by bringing the molten tin removing means 41 into contact with the surface of the roll 121 (122) as described above. Therefore, when the molten tin removing means 41 is brought into contact with the rolls 121 (122), torque is applied to the rolls, which may cause the glass ribbon on the rolls 121 (122) to slip.

Therefore, the molten tin removing means 41 is provided for the roll 121 (122) to which the torque applying means is connected, and the molten tin removing means 41 is brought into contact with the roll 121 (122) 121 (122) to eliminate the influence of the torque generated thereby to suppress the occurrence of slippage.

According to the glass manufacturing method of the present embodiment described above, it is possible to prevent the glass ribbon from sliding on the roll when the glass ribbon is transported by the plurality of rolls. As a result, it is possible to suppress the generation of scratches on the glass ribbon, and to improve the yield of the glass substrate obtained by cutting the glass ribbon.

(Glass manufacturing apparatus)

Next, the glass manufacturing apparatus of the present embodiment will be described.

The glass manufacturing apparatus of the present embodiment may have a float bath and a plurality of rolls for transporting a glass ribbon molded in a float bath.

A torque applying means for applying a torque to the roll may be connected to at least one of the plurality of rolls.

And the torque applying means may have control means for controlling the torque applied to the connected roll by the torque applying means based on the speed of the glass ribbon.

The glass device of the present embodiment can suitably carry out the above-described production method of glass. Therefore, the description of the elements overlapping with the glass manufacturing method will be omitted.

An example of the construction of an apparatus for producing glass of this embodiment will be described with reference to Figs. 1 and 5. Fig. Fig. 5 schematically shows a configuration example when a roll for conveying the formed glass ribbon is viewed from the conveying direction side of the glass ribbon.

As shown in Fig. 1, the glass manufacturing apparatus of the present embodiment includes a float bath 11, a plurality of rolls (conveying rolls) 121 and 121 for conveying the glass ribbon 13 formed by the float bath 11, 122).

As shown in Fig. 5, the torque applying means 51 for applying a torque to the rolls 121 (122) is connected to at least one of the rolls 121 (122) selected from the plurality of rolls 121, Can be connected. The torque application means 51 may also have control means 52 for controlling the torque applied to the rolls 121 (122) to which the torque applying means 51 is connected.

The control means 52 controls the glass ribbon to be conveyed on the plurality of rolls 121 and 122 and the torque applying means to be connected to the roll 121 (122) It is preferable to control such that the speed difference between the speed of the glass ribbon and the peripheral speed of the roll 121 (122) to which the torque applying means is connected is within a predetermined range at the contact point of the roll 121 (122). Specifically, it is preferable to control the torque applied by the torque applying means to the rolls 121 (122) to which the torque applying means is connected so that the speed of the glass ribbon is within the range of, for example, within ± 1.0%.

The method of controlling the torque applied to the roll 121 (122) to which the torque applying means 51 is connected based on the velocity of the glass ribbon is not particularly limited and may be arbitrarily controlled by the control means 52 . Also, the control based on the velocity of the glass ribbon is not limited to the case where only the velocity of the glass ribbon is used as the control parameter. For example, in combination with other parameters, or when the speed of the glass ribbon is used as one of the parameters in the preliminary test or the like, or when the speed of the glass ribbon is used as a parameter for evaluating the control result .

As a specific method for controlling the torque applied to the rolls 121 (122) based on the speed of the glass ribbon by the control means 52, for example, the following forms are conceivable. The following examples are illustrative of the control method and are not limited to these examples.

For example, as described above, the glass ribbon in the layer is transported by a plurality of rolls rotationally driven at the same speed preset by the speed controller, and the peripheral speed of the roll set by the speed controller is set to the speed of the glass ribbon . Based on the speed difference between the peripheral speed of the roll actually detected with respect to the roll 121 (122) to which the torque applying means 51 is connected and the speed of the glass ribbon, the control means 52 controls the torque applying means 51 can control the torque applied to the roll 121 (122) to which the torque applying means 51 is connected.

The preliminary test is carried out as described above so that the speed difference between the velocity of the glass ribbon and the velocity of the actually detected roll 121 (122) relative to the roll 121 (122) to which the torque applying means is connected is within a predetermined range It is possible to select the magnitude of the torque applied by the torque applying means 51 in advance. In manufacturing the product, the torque applying means 51 can apply a torque of a size selected from the result of the preliminary test to the rolls 121 (122) to which the torque applying means 51 is connected.

Further, it may further have glass ribbon speed detecting means (not shown) for detecting the speed of the glass ribbon. The control means 52 then determines whether or not the torque application means 51 is applied to the roll 121 (122) to which the torque application means 51 is connected based on the velocity of the glass ribbon detected by the glass ribbon speed detection means Torque can be controlled. Since the point at which the glass ribbon velocity detecting means detects the velocity has already been described, the description is omitted. Further, a roll circumferential velocity detecting means for detecting the circumferential velocity of the roll 121 (122) may be further provided. In this case, on the basis of the speed of the glass ribbon detected by the glass ribbon speed detecting means and the peripheral speed of the roll 121 (122) detected by the roll circumferential speed detecting means, 121 (122).

As another control method, the control means 52 controls the roll 121 (122) by the torque applying means 51 so that the torque applied to the roll 121 (122) is balanced, (122)) by applying a torque. Since the control method in this case has already been described in the manufacturing method of the glass ribbon, its explanation is omitted.

In addition to the above-described members, an arbitrary member can be added to the glass manufacturing apparatus of the present embodiment.

There may be further provided a molten tin removing means capable of removing molten tin adhering to the surface of the selected roll by sliding contact with the selected roll, for example, below one or more selected rolls of the plurality of rolls .

By providing the molten tin removing means, even when molten tin adheres to the surface of the roll, it can be easily removed, and occurrence of scratches on the lower surface of the glass ribbon can be suppressed. However, since the molten tin removing means is in contact with the surface of the roll, torque is applied to the roll by bringing the molten tin removing means into contact with the roll, which may cause slippage in the transported glass ribbon. Therefore, it is preferable that the molten tin removing means is provided for the roll to which the torque applying means is connected, and the molten tin removing means is brought into contact with the roll, thereby eliminating the influence of the torque generated in the roll to suppress the occurrence of slippage Do.

According to the glass manufacturing apparatus of the present embodiment described above, it is possible to prevent the glass ribbon from sliding on the roll when the glass ribbon is transported by the plurality of rolls. As a result, it is possible to suppress the generation of scratches on the glass ribbon, and to improve the yield of the glass substrate obtained by cutting the glass ribbon.

[Example]

Hereinafter, specific examples will be described, but the present invention is not limited to these examples.

[Roll Perimeter Velocity Measurement Test]

First, as a preliminary test, a roll testing machine to which a torque applying means is connected is installed in a conveying step, and a torque applied by the torque applying means to the roll to which the torque applying means is connected is variously changed, A test was performed to measure the peripheral speed. In the preliminary test, the roll 122 in the glass manufacturing apparatus shown in Fig. 1 was replaced with a roll tester to which a torque application means was connected. 6 is a diagram showing the arrangement and configuration of rolls (roll tester) to which torque applying means are connected.

6, a motor serving as a torque application means 63 capable of applying a desired torque to the roll 122 is disposed on one side (right side in the figure) of the roll 122. [ Between the roll 122 and the torque applying means 63 is disposed an electromagnetic clutch 64 capable of blocking the transmission of the power from the torque applying means 63 to the roll 122. [ And a torque system 65 capable of measuring the torque applied to the roll 122 by the torque applying means 63 is arranged. And an encoder for measuring the peripheral velocity of the roll 122 is disposed (not shown).

On the other side (left side in the figure) of the roll 122, a motor 61 for rotating the roll 122 at a constant speed is connected. At this time, a one-way clutch 62 is disposed between the motor 61 and the roll 122, and the motor 61 is rotated by a speed controller different from the conveying step so that the peripheral speed of the roll 122 is 670 m / .

In this preliminary test, when the glass is being manufactured, the glass substrate is conveyed so that the peripheral speed of the roll set by the speed controller in the conveying step, that is, the conveying speed of the glass ribbon is 680 m / h and the thickness of the glass ribbon is 0.7 mm Controlled by the speed controller of the process. Specifically, a motor (not shown) connected to the roll 121 was rotated such that the peripheral speed of the roll 121 was 680 m / h.

Therefore, from the value of the torque applied to the roll to which the torque applying means is connected by the torque applying means, the circumferential speed of the roll to which the torque applying means is connected becomes 680 m / h in the state of FIG. 2A Is expected. However, since the torque applied to the roll deviates from the ideal state and is only rotated by the rotation of the motor 61 in the state of FIG. 2B, it is expected to be 670 m / h.

In this preliminary test, the torque application means 63 controls the torque applied to the rolls 122 to be the values shown in Table 1 below, respectively, in Examples 1 to 10, The roll speed (peripheral speed of the roll) was measured.

The results of the above test are shown in Table 1. The roll speed (circumferential speed of the roll) was measured by an encoder provided on the roll rotation axis, and the measured value was divided by 680 and multiplied by 100, which was a speed ratio.

In Example 10, it was confirmed that the measurement was not possible because the peripheral speed of the roll exceeded the measurement range of the encoder, but it was 690 m / h or more.

Based on the above results, the following findings were obtained.

When the torque applied to the roll by the torque applying means is 3.4 N · m to 13.6 N · m, the speed of the glass ribbon (= the circumferential speed of the roll in the conveying step) It is possible to make the speed difference with the peripheral speed within +/- 0.25%.

When the torque applied to the roll by the torque applying means is less than 3.4 Nm, the running resistance torque becomes large, and the glass ribbon can not rotate the roll.

If the torque applied to the roll by the torque applying means exceeds 13.6 Nm, the torque applying means increases the torque for rotating the roll, and further increases the applied torque, the peripheral speed of the roll is accelerated.

[Example 1]

In this embodiment, the torque applying means is connected to the roll 122 of the glass manufacturing apparatus shown in Fig. 1 as shown in Fig. 6, and a torque having the same value as that of the preliminary test Example 6 is set To prepare a glass.

The production of glass using the above-described apparatus for producing glass was disclosed.

Specifically, the molten glass of soda lime glass is supplied onto the molten tin 111 filled in the float bath 11 and the glass is discharged from the float bath outlet 112 side of the float bath 11 in the direction of the layer 12 To form a ribbon-shaped glass ribbon 13.

The glass ribbon 13 taken out from the float bath 11 is placed on the roll 122 to which the above torque application means 63 is connected and on the plurality of rolls 121, To the conveying process. The circumferential speed of the plurality of rolls 121 was set to 680 kPa. In the conveying step, the glass ribbon 13 is conveyed in the layer 12 by the plurality of rolls 121 to perform the slow cooling. And cut into a size of 1.2 m x 0.7 m with respect to the cold glass ribbon 13 to obtain a glass substrate. The thickness of the glass substrate produced in this example was 0.7 mm.

In this embodiment, a constant torque of 5.9 Nm is applied to the roll 122 by the torque application means 63 as in the case of Example 6, and the motor 61 rotates the roll 122 And rotated by a speed controller different from the conveying step so that the peripheral speed was 670 m / h.

It was confirmed that the speed difference between the speed of the glass ribbon and the circumferential speed of the roll connected with the torque applying means can be controlled within at least ± 0.14% based on the speed of the glass ribbon. After a 1 hour from the start of the production of the glass, the glass substrate was allowed to stand in a steady state and then subjected to a strict visual inspection on the glass substrate produced in one hour. As a result, on the surface of the glass substrate of 18% There was a flaw.

[Comparative Example 1]

A glass was produced in the same manner as in Example 1 except that the transmission of power from the torque applying means 63 to the roll 122 was cut off by the electromagnetic clutch 64. [

The speed difference between the speed of the glass ribbon and the circumferential speed of the roll connected with the torque application means is not measured but it is assumed that the speed difference becomes larger than that of the preliminary test Example 1 in which the torque of 0.3 N m is applied. That is, the speed difference is estimated to be at least ± 1.46% or more. The glass substrates produced in one hour after the start of the production of glass were inspected in the same manner as in Example 1 to obtain a glass substrate with a 24% There were scratches.

From the above results, it can be understood from the above-mentioned results that the torque applied by the torque applying means is controlled so that the difference in speed between the glass ribbon and the peripheral speed of the roll is at a contact point between the glass ribbon and the roll to which the torque application means is connected, , It was confirmed that the occurrence of scratches on the glass ribbon can be reduced as compared with Comparative Example 1. [ This is considered to be because the glass ribbon in Example 1 was prevented from sliding on the roll.

According to the present invention, for example, when the glass ribbon causes heat shrinkage, the glass ribbon can be prevented from slipping on the roll due to the change of the transport speed of the glass ribbon relative to the peripheral speed of the roll, Occurrence of periodic scratches in the flow direction of the ribbon can be reduced. Therefore, it is possible to improve the production efficiency of glass more than the conventional ones.

11: Float bath
111: molten tin
112: Float Bath exit
12: Layer
121, 122, 21: Roll
13, 22: Glass ribbon
23: contact point
41: molten tin removing means
51, 63: torque applying means
52:
61: Motor
62: One Way Clutch
64: electromagnetic clutch
65: Torque system

Claims (9)

And a transporting step of disposing a glass ribbon formed by a float bath above a plurality of rolls and transporting the glass ribbon by the plurality of rolls,
A torque applying means for applying a torque to the roll is connected to at least one of the plurality of rolls,
In the carrying step,
Wherein the torque applying means controls the torque applied to the connected roll by the torque applying means based on the speed of the glass ribbon. The method according to claim 1,
A speed difference between a speed of the glass ribbon and a peripheral speed of the roll to which the torque applying means is connected is set to be within a range of +/- 1.0% based on the speed of the glass ribbon, The torque application means controls the torque applied to the roll to which the torque application means is connected. 3. The method according to claim 1 or 2,
In the carrying step,
Detecting the speed of the glass ribbon,
And the torque application means controls the torque applied to the roll to which the torque application means is connected based on the detected velocity of the glass ribbon. 4. The method according to any one of claims 1 to 3,
Wherein a thickness of the glass produced by the glass manufacturing method is 1.0 mm or less. 5. The method according to any one of claims 1 to 4,
Wherein the molten tin removing means is disposed below the selected one or more rolls of the plurality of rollers so as to be slidable,
Wherein said molten tin removing means is brought into sliding contact with a selected roll to remove molten tin adhering to the surface of the selected roll. With float baths,
A plurality of rolls for conveying the glass ribbon formed in the float bath,
A torque application means for applying a torque to the roll is connected to at least one of the plurality of rolls,
And the torque applying means has control means for controlling the torque applied to the roll to which the torque applying means is connected based on the speed of the glass ribbon. The method according to claim 6,
Wherein a speed difference between a speed of the glass ribbon and a peripheral speed of the roll to which the torque applying means is connected is greater than a speed difference between the glass ribbon conveyed on the plurality of rolls and a speed to which the torque applying means is connected, The torque application means controls the torque applied to the roll to which the torque application means is connected so that the torque application means is within ± 1.0% with respect to the torque application means. 8. The method according to claim 6 or 7,
Further comprising glass ribbon speed detecting means for detecting the speed of the glass ribbon,
Wherein the control means controls the torque applied by the torque applying means to the roll to which the torque applying means is connected based on the speed of the glass ribbon detected by the glass ribbon speed detecting means. 9. The method according to any one of claims 6 to 8,
Further comprising molten tin removing means capable of removing molten tin adhering to the surface of the selected roll by sliding contact with a selected roll below the selected one or more of the plurality of rolls.

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