JPH0733456A - Production of plate glass - Google Patents

Abstract

PURPOSE:To greatly enhance the production yield by generating a strip at an edge part of a glass ribbon which does not become a product. CONSTITUTION:In the plate glass production device, the device is provided with a flow path 2 of molten glass continuously supplying the molten glass to a forming roll, and the flow path of the molten glass is constituted of a lip tile 3 and a guide block 4, and the molten glass is formed to the glass ribbon with the forming roll. In the inside surface 11 of the molten glass path, a groove part 12 is provided in the flow direction of the molten glass.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate glass manufacturing apparatus.

[0002]

2. Description of the Related Art An apparatus for producing sheet glass, which continuously supplies molten glass to a forming roll and forms the molten glass into a glass ribbon, is widely used for producing sheet glass such as template glass.

As shown in FIG. 2, which is a horizontal cross-sectional view, such a sheet glass manufacturing apparatus has a molten glass passage 2 for supplying molten glass to a forming roll 1. The flow path of the molten glass has a lip tile 3 and a guide block 4, and the inner surface of the guide block 4 is a flat surface. The molten glass passes through the molten glass flow path 2 from above, passes through the gap between the two forming rolls 1 and is rolled to form the glass ribbon 8
And is conveyed to the annealing furnace by the conveyor roll 7.

However, the glass ribbon manufactured by such a manufacturing apparatus has a problem that a streak is generated in the central portion of the product, and the yield of the product is reduced.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and to provide an apparatus for producing a sheet glass in which a glass ribbon having a stripe at the edge and having no stripe at the center can be obtained. .

[0006]

According to the present invention, there is provided a molten glass passage having a lip tile and a guide block for continuously supplying the molten glass to a forming roll. And a guide block,
In a plate glass manufacturing apparatus for forming molten glass into a glass ribbon by a forming roll, a plate glass manufacturing apparatus is characterized in that a groove portion is provided in an inner surface of a molten glass flow path in a flowing direction of the molten glass.

A description will be given below with reference to the drawings. 1 is a partial perspective view of a flat glass manufacturing apparatus according to the present invention, which is the same as FIG. 1 except for the shape of a guide block 4. As shown in the figure, the flow path 2 for molten glass has a lip tile 3 and a guide block 4 provided on the lip tile 3, and the molten glass flows through the flow path 2 for molten glass from left to right. Although not shown in the drawing, it is rolled by two forming rolls and formed into a glass ribbon. This glass ribbon is carried into a slow cooling furnace, slowly cooled, and then cut.

A groove 12 is formed on the inner surface 11 of the guide block 4 in the flow direction of the molten glass. The groove portion has a function of bringing the generation portion of the streak toward the edge portion of the glass ribbon which does not become a product, and the center portion thereof is located slightly below the surface 13 of the molten glass and slightly above the upper surface of the lip tile 3.

Specifically, it is preferable that the upper end 14 of the groove is provided at a position 15 to 20 mm below the surface 13 of the molten glass. If the upper end 14 of the groove portion is higher than this range, the molten glass is cooled and devitrification is likely to occur inside the groove portion, which is not preferable. On the other hand, if the upper end of the groove is too lower than this range, it is not preferable because the function of bringing the region where the streak is generated closer to the edge of the glass ribbon is reduced.

If the lower end 15 of the groove portion is too low, devitrification is likely to occur inside the groove portion, and if it is too high, the action of bringing the region where streaks occur toward the edge portion of the glass ribbon is unfavorable. The lower end 15 of the groove portion is preferably located 110 to 125 mm above the upper surface of the lip tile 3.

The depth of the groove 12 is preferably in the range of 20 to 50 mm. If the depth is less than 20 mm, the action of pulling the streak portion toward the edge of the glass ribbon is lowered, which is not preferable, and if it exceeds 50 mm, devitrification is likely to occur inside the groove, and the ears of the glass ribbon are easily generated. Is relatively unfavorably increased, resulting in a decrease in yield.

The width W of the groove 12 is preferably in the range of 95 to 100 mm. If the width is less than 95 mm, the action of pulling the streak generation site toward the edge of the glass ribbon is reduced, and the width is 100 mm.
If it exceeds, devitrification is likely to occur inside the groove, which is not preferable.

The length of the groove 12 is 320 to 3
A range of 30 mm is preferred. If this length is less than 320 mm, the action of bringing the streak generation site closer to the edge of the glass ribbon is reduced, and if it exceeds 330 mm, devitrification is likely to occur inside the groove, which is not preferable.

The lower end 15 of the groove portion 12 is curved downward near the tip as in the upper surface of the lip tile 3, but the upper end 14 of the groove portion is straight to the tip.

As a material for such a guide block, chamotte brick is preferable because it is excellent in workability.

The forming roll used in the present invention is
It may be either one for producing a so-called template glass by forming an uneven pattern on its surface, or one for producing a flat plate glass having no uneven pattern on the surface.

Further, as the composition of the plate glass to be produced, a wide range of compositions such as soda-lime-silica glass and borosilicate glass used for ordinary window glass are used.

[0018]

According to the present invention, since streaks are generated at the edge of the glass ribbon which does not become a product, the production yield can be greatly improved.

[Brief description of drawings]

FIG. 1 is a partial perspective view of a flat glass manufacturing apparatus according to the present invention.

FIG. 2 is a horizontal sectional view of a conventional device.

[Explanation of symbols]

 2: Flow path of molten glass 3: Lip tile 4: Guide block 5: Groove

Claims (1)

[Claims] 1. A molten glass flow path for continuously supplying molten glass to a forming roll, wherein the molten glass flow path comprises a lip tile and a guide block, and the forming roll forms the molten glass into a glass ribbon. An apparatus for producing a sheet glass to be formed, characterized in that a groove portion is provided in an inner surface of the molten glass flow path in a flow direction of the molten glass.