JP2021066631A - Agitator and method for manufacturing glass - Google Patents

Abstract

To provide an agitator capable of promoting the homogenization of molten glass by reducing places having a relatively slow flow rate of the molten glass in the vessel of an agitator, and a method for manufacturing glass.SOLUTION: An agitator 11 includes a vessel 12 and a stirrer 13 for agitating molten glass MG in the vessel 12. The vessel 12 of the agitator 11 has an inflow port 12c for entering the molten glass MG into the vessel 12, and an outflow port 12d for draining the molten glass MG in the vessel 12; the inner surface 12a of the vessel 12 in the agitator 11 includes an inner bottom S1 and an inner side surface S2; and the inner surface 12a of the vessel 12 includes a curved surface S3 connecting to the inner bottom S1 and the inner side surface S2 between the inner bottom S1 and the inner side surface S2 and convex toward the outside of the vessel 12.SELECTED DRAWING: Figure 1

Description

The present invention relates to a stirrer for stirring molten glass and a method for producing glass.

As disclosed in Patent Document 1, in the glass manufacturing method, a stirring device for stirring the molten glass is used in order to homogenize the molten glass obtained by melting the glass raw material in a melting furnace. The stirrer includes a container and a stirrer that stirs the molten glass in the container.

Japanese Unexamined Patent Publication No. 2008-156223

In the above-mentioned conventional stirring device, when the molten glass in the container is stirred by the stirrer, there are relatively many places in the container where the flow velocity of the molten glass is relatively slow. Therefore, the molten glass tends to become heterogeneous glass at a place where the flow velocity is slow, and there is a possibility that the heterogeneous glass may cause a decrease in the homogeneity of the molten glass and a decrease in the quality of the obtained glass product.

The present invention has been made in view of these circumstances, and an object of the present invention is to promote homogenization of the molten glass by reducing the places where the flow velocity of the molten glass is relatively slow in the container of the stirring device. It is an object of the present invention to provide a stirrer and a method for producing glass.

The stirring device for solving the above problems is a stirring device including a container and a stirrer for stirring the molten glass in the container, and the container includes an inflow port into which the molten glass flows into the container and the above. The container is provided with an outlet for flowing out the molten glass in the container, and the inner surface of the container is formed on the inner bottom surface, the inner surface surface, and the inner bottom surface and the inner surface surface between the inner bottom surface and the inner surface surface. It has a curved surface that is continuous and convex toward the outside of the container.

According to this configuration, among the inner surfaces of the container of the stirring device, the inner bottom surface and the inner side surface are formed by a curved surface that is continuous with the inner bottom surface and the inner side surface and is convex toward the outside of the container. Therefore, it is possible to promote the flow of the molten glass in the vicinity of the outer periphery of the inner bottom surface of the container.

In the stirring device, when the container has a columnar hollow portion surrounded by the inner side surface, the inner diameter of the container is D, and the radius of curvature of the curved surface is R, the relationship of the following formula (1) It is preferable to satisfy.

0.01 × D ≦ R ・ ・ ・ (1)
In the stirring device, the radius of curvature of the curved surface preferably satisfies the relationship of the following formula (2).

R ≦ 0.45 × D ・ ・ ・ (2)
In the stirring device, the radius of curvature R of the curved surface is preferably in the range of 2 mm or more and 60 mm or less.

In the stirring device, the minimum value of the distance between the inner bottom surface of the container and the stirrer, the minimum value of the distance between the inner side surface of the container and the stirrer, and the minimum distance between the curved surface of the container and the stirrer. The value is preferably 1.5 mm or more.

In the stirring device, the distance between the curved surface of the container and the stirrer is preferably 30 mm or less.
In the stirring device, the outlet is preferably opened to the curved surface.

According to this configuration, the flow of the molten glass in the vicinity of the outlet of the container can be promoted, so that the more homogenized molten glass can flow out from the outlet.
In the stirring device, the stirrer includes a rotating shaft and a rod-shaped blade group composed of a plurality of rod-shaped blades provided on the rotating shaft, and the plurality of rod-shaped blades are orthogonal to the axial direction of the rotating shaft. It is preferable that they project in different directions from the rotation axis so that they are arranged in the same plane.

According to this configuration, it is possible to increase the flow velocity in the layered region where the rod-shaped blades are arranged in the molten glass.
In the stirring device, the stirrer preferably includes the rod-shaped blade group arranged at a position surrounded by the curved surface.

According to this configuration, the flow of the molten glass in the vicinity of the outer periphery of the inner bottom surface of the container can be further promoted.
In the stirring device, the stirrer may include a plurality of rod-shaped blade groups arranged apart from each other in the axial direction of the rotating shaft.

According to this configuration, it is possible to further reduce the locations where the flow velocity of the molten glass is relatively slow in the container of the agitator.
In the stirring device, the stirrer may further include screw blades provided on the rotating shaft, and the rod-shaped blade group may be arranged on the inner bottom surface side of the container with respect to the screw blades.

The glass manufacturing method is a glass manufacturing method including a stirring step of stirring molten glass using a stirrer, and the stirrer includes a container and a stirrer for stirring the molten glass in the container. The container includes an inflow port for flowing the molten glass into the container and an outlet for flowing out the molten glass in the container, and the inner surface of the container includes an inner bottom surface, an inner surface surface, and the above. It has a curved surface that is continuous with the inner bottom surface and the inner surface surface and is convex toward the outside of the container between the inner bottom surface and the inner surface surface.

In the glass manufacturing method, a clarification step for clarifying the molten glass may be provided as a pre-step of the stirring step.
In the method for producing glass, the container of the stirrer has an inflow port for flowing the molten glass into the container and an outflow port for flowing out the molten glass in the container. The stirrer is provided with a rotation shaft and a rod-shaped blade group composed of a plurality of rod-shaped blades provided on the rotation shaft, and the plurality of rod-shaped blades are provided in the axial direction of the rotation shaft. The stirrer includes a group of rod-shaped blades that are arranged in different directions from the rotation axis so as to be arranged in the same plane orthogonal to the curved surface, and the stirrer is arranged at a position surrounded by the curved surface. It is preferable to rotate the stirrer so that the number of rod-shaped blades passing through the outlet is 120 or more per minute.

According to this method, the flow of the molten glass in the vicinity of the outlet of the container can be promoted, so that the more homogenized molten glass can flow out from the outlet. Further, by rotating the stirrer as described above, the pulsation of the molten glass flowing out from the outlet of the container of the stirring device can be suppressed.

According to the present invention, it is possible to promote the homogenization of the molten glass by reducing the places where the flow velocity of the molten glass is relatively slow in the container of the stirring device.

It is sectional drawing which shows the stirring apparatus in embodiment. It is sectional drawing which follows the line 2-2 of FIG. It is a graph which shows the relationship between the radius of curvature on the curved surface of a container, and the volume ratio of a stagnation area.

Hereinafter, an embodiment of a stirring device and a method for manufacturing glass will be described with reference to the drawings. In the drawings, for convenience of explanation, a part of the configuration may be exaggerated or simplified. In addition, the dimensional ratio of each part may differ from the actual one.

As shown in FIGS. 1 and 2, the stirring device 11 includes a container 12 and a stirrer 13 for stirring the molten glass MG in the container 12. The inner surface 12a of the container 12 in the stirring device 11 has an inner bottom surface S1 and an inner surface surface S2. The inner surface 12a of the container 12 further has a curved surface S3 that is connected to the inner bottom surface S1 and the inner side surface S2 between the inner bottom surface S1 and the inner side surface S2 and is convex toward the outside of the container 12. The inner bottom surface S1 is preferably a flat surface.

The container 12 of the stirring device 11 has a columnar hollow portion 12b surrounded by the inner side surface S2 of the container 12.
When the inner diameter of the container 12 of the stirring device 11 is D and the radius of curvature of the curved surface S3 of the container 12 is R, it is preferable to satisfy the relationship of the following formula (1). The inner diameter D is the inner diameter of the container 12.

0.01 × D ≦ R ・ ・ ・ (1)
By increasing the radius of curvature R of the curved surface S3 of the container 12 according to the inner diameter of the container 12, the flow of the molten glass MG along the curved surface S3 of the container 12 can be further promoted.

The radius of curvature R of the curved surface S3 of the container 12 preferably satisfies the relationship of the following equation (2).
R ≦ 0.45 × D ・ ・ ・ (2)
Here, if the radius of curvature R is too large, the curved surface S3 and the stirrer 13 may easily interfere with each other at the bottom of the container 12, or a stagnant layer may easily occur at the bottom. By appropriately limiting the radius of curvature R of the curved surface S3 of the container 12 as in the above equation (2), a sufficient space for arranging the stirrer 13 can be secured.

The inner diameter D of the container 12 of the stirring device 11 is preferably 100 mm or more. The inner diameter D of the container 12 of the stirring device 11 is preferably 350 mm or less.
The inner diameter D of the container 12 indicates the inner diameter of the cylindrical hollow portion 12b surrounded by the inner side surface S2. The inner diameter D of the hollow portion 12b of the present embodiment is constant, but when the inner diameter is not constant, the inner diameter D of the container 12 indicates the inner diameter of the hollow portion 12b formed by the inner side surface S2 adjacent to the curved surface S3.

The radius of curvature R of the curved surface S3 of the container 12 is more preferably 2 mm or more. The radius of curvature R of the curved surface S3 of the container 12 is more preferably 60 mm or less.
The minimum value W1 of the distance between the inner bottom surface S1 of the container 12 and the stirrer 13, the minimum value W2 of the distance between the inner surface S2 of the container 12 and the stirrer 13, and the minimum value W3 of the distance between the curved surface S3 of the container 12 and the stirrer 13. Is preferably 1.5 mm or more. These intervals refer to the intervals of the narrowest part of the interval between the outermost circumference of the trajectory of the stirrer 13 when the stirrer 13 is rotated and the inner surface 12a of the container 12. By widening these intervals, for example, even if the relative positions of the stirrer 13 and the inner surface 12a of the container 12 are temporarily excessively displaced, the contact between the stirrer 13 and the inner surface 12a of the container 12 Is more likely to be avoided.

The minimum value W3 of the distance between the curved surface S3 of the container 12 and the stirrer 13 is preferably 30 mm or less, more preferably 20 mm or less, further preferably 10 mm or less, and most preferably 5 mm or less, for example. It may be 4 mm or less. By narrowing the minimum value W3 of the distance between the curved surface S3 of the container 12 and the stirrer 13, the flow of the molten glass MG along the curved surface S3 of the container 12 can be further promoted.

The container 12 of the stirring device 11 has an inflow port 12c for flowing the molten glass MG into the container 12 and an outflow port 12d for flowing out the molten glass MG in the container 12. The stirring device 11 can continuously perform the inflow and outflow of the molten glass MG. The inflow port 12c of the container 12 is provided above the outflow port 12d of the container 12. The outlet 12d of the container 12 is open to the inner side surface S2 of the container 12. The outlet 12d of the container 12 is open to the curved surface S3 on the inner surface 12a of the container 12.

Next, the details of the stirrer 13 of the stirring device 11 will be described.
The stirrer 13 includes a rotating shaft 14 and a rod-shaped blade group 15 composed of a plurality of rod-shaped blades BL provided on the rotating shaft 14. The plurality of rod-shaped blades BL constituting the rod-shaped blade group 15 project from the rotating shaft 14 in different directions so as to be arranged in the same plane orthogonal to the axial direction of the rotating shaft 14.

The stirrer 13 of the present embodiment includes a plurality of rod-shaped blade groups 15. The plurality of rod-shaped blade groups 15 include a first rod-shaped blade group 15a and a second rod-shaped blade group 15b provided on the proximal end side of the rotating shaft 14 with respect to the first rod-shaped blade group 15a. That is, the first rod-shaped blade group 15a is located on the inner bottom surface S1 side (lower side) of the container 12 with respect to the second rod-shaped blade group 15b.

The first rod-shaped blade group 15a is arranged at a position surrounded by the inner surface 12a of the container 12. The first rod-shaped blade group 15a is viewed in an orthogonal direction orthogonal to the axial direction of the rotating shaft 14, so that at least a part of each rod-shaped blade BL of the first rod-shaped blade group 15a overlaps with the outlet 12d of the container 12. Is located in. The first rod-shaped blade group 15a is arranged at a position where the entire rod-shaped blade BL of the first rod-shaped blade group 15a overlaps with the outlet 12d of the container 12 in an orthogonal direction view orthogonal to the axial direction of the rotation axis 14. It is preferable to have. The tip of each rod-shaped blade BL constituting the first rod-shaped blade group 15a periodically passes through a position facing the outlet 12d of the container 12 in a plan view orthogonal to the axial direction of the rotating shaft 14. The second rod-shaped blade group 15b is arranged at a position surrounded by the inner side surface S2 of the container 12. The second rod-shaped blade group 15b is arranged on the inner bottom surface S1 side of the container 12 with respect to the inflow port 12c of the container 12 in an orthogonal direction view orthogonal to the axial direction of the rotation axis 14.

As shown in FIG. 2, the first rod-shaped blade group 15a is composed of four rod-shaped blades BL arranged in a cross shape in a plan view orthogonal to the axial direction of the rotating shaft 14. The second rod-shaped blade group 15b is composed of two rod-shaped blades BL protruding in directions opposite to each other in the plan view. The number of rod-shaped blades BL of the first rod-shaped blade group 15a and the number of rod-shaped blades BL of the second rod-shaped blade group 15b are not particularly limited. For example, the number of rod-shaped blades BL of the first rod-shaped blade group 15a and the number of rod-shaped blades BL of the second rod-shaped blade group 15b may be the same. Further, for example, the number of rod-shaped blades BL of the second rod-shaped blade group 15b may be larger than the number of rod-shaped blades BL of the first rod-shaped blade group 15a. For example, from the viewpoint of promoting the flow of the molten glass MG in the vicinity of the inner bottom surface S1 of the container 12, the number of rod-shaped blades BL in the first rod-shaped blade group 15a is preferably larger than the number of second rod-shaped blades.

The stirrer 13 of the present embodiment further includes a screw blade 16 provided on the rotating shaft 14. The shape of the screw blade 16 is, for example, a spiral shape. The screw blade 16 is arranged closer to the base end side of the rotating shaft 14 than the rod-shaped blade group 15. That is, the rod-shaped blade group 15 is arranged on the inner bottom surface S1 side of the container 12 with respect to the screw blade 16.

The screw blades 16 are arranged so that at least a part of the screw blades 16 overlaps the inflow port 12c of the container 12 in an orthogonal direction view orthogonal to the axial direction of the rotation shaft 14. The liquid level of the molten glass MG in the container 12 is above the inflow port 12c of the container 12 and above the screw blade 16.

At least the inner surface 12a of the container 12 of the above-mentioned stirring device 11 and at least the outer surface of the stirrer 13 are preferably formed of, for example, platinum or a platinum alloy from the viewpoint of enhancing corrosion resistance.

The base end portion of the rotary shaft 14 of the stirrer 13 of the stirrer 11 is rotationally driven by being connected to a drive source 17 such as a motor. The stirring device 11 constitutes a part of a glass article manufacturing device. The glass article manufacturing apparatus includes, for example, a clarification device arranged on the upstream side of the stirring device 11 and a molding device arranged on the downstream side of the stirring device 11. The glass flowing out of the stirring device 11 is molded into, for example, a plate shape using a molding device. Examples of the molding method used in the molding apparatus include an overflow down draw method, a down draw method (slot down method, redraw method, etc.), a float method, a rollout method, and the like. The molding apparatus may be an apparatus for molding a glass ingot from molten glass MG and cutting the glass ingot.

Next, a method for manufacturing glass will be described.
The glass manufacturing method includes a stirring step of stirring the molten glass MG using the stirring device 11. The glass manufacturing method of the present embodiment includes a clarification step of clarifying the molten glass MG as a pre-step of the stirring step. The glass obtained by the glass manufacturing method is molded by a molding apparatus to obtain a glass article. In the stirring step of the present embodiment, the viscosity of the glass in the container 12 of the stirring device 11 is, for example, in the range of 1.5 Pa · s or more and 3.0 Pa · s or less.

Here, when the outlet 12d of the container 12 opens to the curved surface S3 of the container 12 and the first rod-shaped blade group 15a is arranged at a position surrounded by the curved surface S3 of the container 12 as in the stirring device 11, the first rod-shaped blade group 15a is arranged. The molten glass MG flowing out from the outlet 12d of the container 12 pulsates as each rod-shaped blade BL of the rod-shaped blade group 15a rotates. By suppressing the pulsation of such molten glass MG, for example, the molding of glass in a molding apparatus can be stabilized. From the viewpoint of suppressing the pulsation of the molten glass MG flowing out from the outlet 12d of the container 12 of the stirring device 11, in the stirring step, the number of rod-shaped blades BL passing through the outlet 12d of the container 12 per minute is 120. It is preferable to rotate the stirrer 13 so as to be as described above, and it is more preferable to rotate the stirrer 13 so as to be 200 or more. For example, from the viewpoint of suppressing the vibration of the stirrer 13, in the stirring step, the stirrer 13 may be rotated so that the number of rod-shaped blades BL passing through the outlet 12d of the container 12 per minute is 1000 or less. preferable.

The number of rod-shaped blades BL passing through the outlet 12d of the container 12 per minute can be set by the number of rod-shaped blades BL of the first rod-shaped blade group 15a and the rotation speed of the stirrer 13 per minute. For example, as the number of rod-shaped blades BL of the first rod-shaped blade group 15a of the present embodiment decreases, it is necessary to increase the rotation speed of the stirrer 13 per minute. For example, from the viewpoint of suppressing the vibration of the stirrer 13 by reducing the rotation speed of the stirrer 13 per minute, the number of rod-shaped blades BL of the first rod-shaped blade group 15a is preferably two or more, more preferably. Is 3 or more, more preferably 4 or more.

The obtained glass (molten glass MG) is sent from the stirring device 11 to the molding device and then molded by the molding device to obtain a glass article.
Next, the result of analyzing the flow state of the molten glass using the analysis model will be described.

The analysis model of the flow state was created based on the stirring device 11 shown in FIGS. 1 and 2. In the description of the analysis model, the reference numerals of the members of the stirring device 11 are omitted.
Three types of analysis models were created in which the radius of curvature R on the curved surface of the container of the stirrer was changed, and the relationship between the radius of curvature R on the curved surface of the container and the flow velocity of the molten glass in the container was analyzed. An example of the analysis conditions is as follows.

Viscosity of molten glass: 3.0 [Pa · s]
Flow rate of molten glass: 15 [kg / hr]
Stirrer rotation speed: 50 [rpm]
Temperature of molten glass: 850 [° C]
The inner diameter D of the container in the stirrer of the analysis model is 140 mm. The minimum value of the distance between the inner bottom surface of the container and the stirrer, the minimum value of the distance between the inner surface of the container and the stirrer, and the minimum value of the distance between the curved surface of the container and the stirrer are all 1.5 mm or more.

The radius of curvature R of the curved surface of the three types of analysis models was set to 10 mm, 30 mm, and 50 mm, respectively. From the three types of analysis models, a region where the flow velocity of the molten glass was 0.00050 [m / s] or less was set in advance as a stagnant region where the molten glass was stagnant in the container, and the volume of the stagnant region was calculated.

FIG. 3 is a graph showing the relationship between the radius of curvature R on the curved surface of the container and the volume ratio of the stagnant region. In this graph, the volume of the stagnant region in the analysis model having the radius of curvature R of 10 mm is set to 100 [%], and the volume ratio of the stagnant region in each of the analysis models having the radius of curvature R of 30 mm and 50 mm is shown. From this analysis result, it can be seen that the volume of the stagnant region of the molten glass decreases as the radius of curvature R on the curved surface of the container increases. That is, from this analysis result, it can be seen that the larger the radius of curvature R on the curved surface of the container, the easier it is for the molten glass in the container of the agitator to flow along the curved surface of the container.

The above-mentioned equation (1) defines preferable conditions for more reliably obtaining the effect of reducing the stagnation region. Specifically, as shown in the graph of FIG. 3, when the effect of reducing the stagnation region is sufficiently recognized when about 1.4 ≦ R, the above formula (1) is based on 0.01 × 140 ≦ R. ) Is derived.

Further, the above-mentioned formula (2) defines preferable conditions under which sufficient production stability can be obtained. As shown in the graph of FIG. 3, the larger the radius of curvature R, the lower the volume ratio of the stagnation region, which is preferable. However, when the radius of curvature R is extremely large, the minimum value of the distance between the curved surface of the container and the stirrer becomes small. There is concern about interference. When the inner diameter D of the container is 140 mm, the upper limit of the radius of curvature R of the curved surface is set to about 65, so that interference between the curved surface of the container and the stirrer can be prevented more reliably. When a preferable ratio coefficient is obtained from the values of the inner diameter D and the radius of curvature R, R / D = 65/140 ≈ 0.45, and the above equation (2) is derived from the coefficient.

Next, the operation and effect of this embodiment will be described.
(1) The stirring device 11 includes a container 12 and a stirrer 13 for stirring the molten glass MG in the container 12. The container 12 of the stirring device 11 has an inflow port 12c for flowing the molten glass MG into the container 12 and an outflow port 12d for flowing out the molten glass MG in the container 12. The inner surface 12a of the container 12 in the stirring device 11 has an inner bottom surface S1 and an inner surface surface S2. The inner surface 12a of the container 12 in the stirring device 11 further has a curved surface S3 that is continuous with the inner bottom surface S1 and the inner side surface S2 between the inner bottom surface S1 and the inner side surface S2 and is convex toward the outside of the container 12. ing.

According to this configuration, of the inner surface 12a of the container 12 of the stirring device 11, the inner bottom surface S1 and the inner side surface S2 are connected to the inner bottom surface S1 and the inner side surface S2 and are convex toward the outside of the container 12. Since it is formed by the curved surface S3, the flow of the molten glass MG in the vicinity of the outer periphery of the inner bottom surface S1 of the container 12 can be promoted. This makes it possible to promote the homogenization of the molten glass MG by reducing the locations where the flow velocity of the molten glass MG is relatively slow in the container 12 of the stirring device 11.

(2) The outlet 12d of the container 12 is open to the curved surface S3 of the container 12. In this case, since the flow of the molten glass MG in the vicinity of the outlet 12d of the container 12 can be promoted, the more homogenized molten glass MG can be discharged from the outlet 12d.

(3) The stirrer 13 includes a rod-shaped blade group 15. The plurality of rod-shaped blades BL constituting the rod-shaped blade group 15 project from the rotating shaft 14 in different directions so as to be arranged in the same plane orthogonal to the axial direction of the rotating shaft 14. In this case, the flow velocity in the layered region where the rod-shaped blade group 15 is arranged in the molten glass MG can be easily increased.

(4) The stirrer 13 includes a first rod-shaped blade group 15a arranged at a position surrounded by the curved surface S3. In this case, the flow of the molten glass MG near the outer periphery of the inner bottom surface S1 of the container 12 can be further promoted. As a result, it is possible to further promote the homogenization of the molten glass MG by further reducing the locations where the flow velocity of the molten glass MG is relatively slow in the container 12 of the stirring device 11.

(5) The stirrer 13 includes a plurality of rod-shaped blade groups 15 arranged apart from each other in the axial direction of the rotating shaft 14. In this case, it is possible to further promote the homogenization of the molten glass MG by further reducing the locations where the flow velocity of the molten glass MG is relatively slow in the container 12 of the stirring device 11.

(6) The stirrer 13 further includes a screw blade 16 provided on the rotating shaft 14. The rod-shaped blade group 15 is arranged on the inner bottom surface S1 side of the container 12 with respect to the screw blade 16. In this case, it is possible to further promote the homogenization of the molten glass MG by further reducing the locations where the flow velocity of the molten glass MG is relatively slow in the container 12 of the stirring device 11.

(7) In the stirring device 11, the outlet 12d of the container 12 is open to the curved surface S3 of the container 12. The first rod-shaped blade group 15a of the stirrer 13 is arranged at a position surrounded by the curved surface S3 of the container 12. In the stirring step of the glass manufacturing method, it is preferable to rotate the stirrer 13 so that the number of rod-shaped blades BL of the first rod-shaped blade group 15a passing through the outlet 12d of the container 12 is 120 or more per minute. ..

In this case, since the flow of the molten glass MG in the vicinity of the outlet 12d of the container 12 can be promoted, the more homogenized molten glass MG can be discharged from the outlet 12d. Further, by rotating the stirrer 13 as described above, the pulsation of the molten glass MG flowing out from the outlet 12d of the container 12 of the stirring device 11 can be suppressed. Therefore, it is possible to stably produce higher quality glass articles.

(Change example)
This embodiment can be modified and implemented as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

-In the glass manufacturing method, the clarification step may be performed by a clarification device arranged on the downstream side of the melting furnace for melting the glass raw material, or may be performed in the melting furnace.
The stirrer 13 of the stirring device 11 may be changed to a stirrer including a rod-shaped blade group 15 provided on the base end side of the rotating shaft 14 and a stirrer 13 provided with a screw blade 16 on the tip end side of the rotating shaft 14. it can.

-At least one of the first rod-shaped blade group 15a and the second rod-shaped blade group 15b of the stirrer 13 of the stirrer 11 may be omitted. For example, when the first rod-shaped blade group 15a is omitted, the blades are not arranged at the position surrounded by the curved surface S3 of the container 12. Further, the screw blade 16 of the stirrer 13 of the stirring device 11 may be omitted. That is, the blade structure of the stirrer 13 of the stirring device 11 is not limited to the three-stage blade structure of the first rod-shaped blade group 15a, the second rod-shaped blade group 15b, and the screw blade 16. The blade structure of the stirrer 13 of the stirring device 11 may be a one-stage blade structure or a multi-stage blade structure having two or more stages.

The blades of the stirrer 13 of the stirring device 11 are not limited to the rod-shaped blades BL or the screw blades 16, and may be other types of blades. The type of the blade of the stirrer 13 may be only one type, or may be two or more types.

The stirring device 11 may include a plurality of stirrs 13 arranged side by side along the inner bottom surface S1 of the container 12.
The shape of the hollow portion 12b of the container 12 in the stirring device 11 is not limited to a columnar shape, and may be an elliptical columnar shape or a polygonal columnar shape such as a square columnar shape or a pentagonal columnar shape.

The curved surface S3 of the container 12 of the agitator 11 includes the entire outer circumference of the inner bottom surface S1 and the entire outer circumference of the inner side surface S2 from the viewpoint of promoting the flow of the molten glass MG so as to cover the entire outer circumference of the inner bottom surface S1 of the container 12. It is preferable that the curved surface S3 is continuous with, but it may be a curved surface that is continuous with a part of the outer circumference of the inner bottom surface S1 and a part of the outer circumference of the inner side surface S2.

The inflow port 12c of the container 12 of the agitator 11 is provided above the outflow port 12d of the container 12, but is not limited thereto. For example, the inflow port 12c and the outflow port 12d of the container 12 may be provided at the same height position, or the inflow port 12c may be provided below the outflow port 12d. In this case, by adjusting the liquid level height of the molten glass MG on the upstream side or the downstream side of the stirring device 11, the molten glass MG can be continuously circulated in the container 12 of the stirring device 11.

The stirring device 11 is a continuous stirring device 11 capable of continuously supplying the molten glass MG into the container 12 and discharging the molten glass MG from the container 12, but is not limited thereto. .. That is, it can be changed to a batch type agitator.

11 ... Stirrer, 12 ... Container, 12a ... Inner surface, 12b ... Hollow part, 12c ... Inlet, 12d ... Outlet, 13 ... Stirrer, 14 ... Rotating shaft, 15 ... Rod-shaped blade group, 15a ... First rod-shaped blade group , 15b ... 2nd rod-shaped blade group, 16 ... screw blade, BL ... rod-shaped blade, D ... inner diameter, MG ... molten glass, R ... radius of curvature, S1 ... inner bottom surface, S2 ... inner surface surface, S3 ... curved surface, W1, W2 , W3 ... Minimum value.

Claims (14)

A stirring device including a container and a stirrer for stirring the molten glass in the container.
The container includes an inflow port for flowing the molten glass into the container and an outlet for flowing out the molten glass in the container.
The inner surface of the container includes an inner bottom surface, an inner surface surface, a curved surface that is continuous with the inner bottom surface and the inner surface surface between the inner bottom surface and the inner surface surface, and is convex toward the outer side of the container. Has a stirrer. The container has a columnar hollow portion surrounded by the inner side surface, and has a columnar hollow portion.
When the inner diameter of the container is D and the radius of curvature of the curved surface is R, the following equation (1):
0.01 × D ≦ R ・ ・ ・ (1)
The stirring device according to claim 1, wherein the stirring device satisfies the above-mentioned relationship. The radius of curvature of the curved surface is calculated by the following equation (2):
R ≦ 0.45 × D ・ ・ ・ (2)
The stirring device according to claim 2, wherein the stirring device satisfies the above-mentioned relationship. The stirring device according to claim 3, wherein the radius of curvature R of the curved surface is within the range of 2 mm or more and 60 mm or less. The minimum value of the distance between the inner bottom surface of the container and the stirrer, the minimum value of the distance between the inner surface of the container and the stirrer, and the minimum value of the distance between the curved surface of the container and the stirrer are all. The stirring device according to any one of claims 1 to 4, which is 1.5 mm or more. The stirring device according to any one of claims 1 to 5, wherein the distance between the curved surface of the container and the stirrer is 30 mm or less. The stirring device according to any one of claims 1 to 6, wherein the outlet opens on the curved surface. The stirrer includes a rotation shaft and a rod-shaped blade group composed of a plurality of rod-shaped blades provided on the rotation shaft.
The invention according to any one of claims 1 to 7, wherein the plurality of rod-shaped blades project in different directions from the rotating shaft so as to be arranged in the same plane orthogonal to the axial direction of the rotating shaft. Stirrer. The stirring device according to claim 8, wherein the stirrer includes the rod-shaped blade group arranged at a position surrounded by the curved surface. The stirring device according to claim 8 or 9, wherein the stirrer includes a plurality of rod-shaped blade groups arranged apart from each other in the axial direction of the rotating shaft. The stirrer further includes screw blades provided on the rotating shaft.
The stirring device according to any one of claims 8 to 10, wherein the rod-shaped blade group is arranged on the inner bottom surface side of the container with respect to the screw blade. A method for producing glass, which comprises a stirring step of stirring molten glass using a stirring device.
The stirring device includes a container and a stirrer that stirs the molten glass in the container.
The container includes an inflow port for flowing the molten glass into the container and an outlet for flowing out the molten glass in the container.
The inner surface of the container includes an inner bottom surface, an inner surface surface, a curved surface that is continuous with the inner bottom surface and the inner surface surface between the inner bottom surface and the inner surface surface, and is convex toward the outer side of the container. A method for manufacturing glass. The method for producing glass according to claim 12, further comprising a clarification step of clarifying the molten glass as a pre-step of the stirring step. The container of the agitator has an inflow port for flowing the molten glass into the container and an outflow port for flowing out the molten glass in the container, and the outlet opens on the curved surface. ,
The stirrer includes a rotation shaft and a rod-shaped blade group composed of a plurality of rod-shaped blades provided on the rotation shaft.
The plurality of rod-shaped blades project in different directions from the rotation axis so as to be arranged in the same plane orthogonal to the axis direction of the rotation axis.
The stirrer includes the rod-shaped blade group arranged at a position surrounded by the curved surface.
The method for producing glass according to claim 12 or 13, wherein in the stirring step, the stirrer is rotated so that the number of rod-shaped blades passing through the outlet is 120 or more per minute.

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