JPS595530B2 - Method and apparatus for producing thin plates by stretching original glass plates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method and apparatus for obtaining a thin glass plate of any thickness by reheating a thick glass base plate and drawing it into a thin sheet.

There are various methods for manufacturing thin glass sheets, such as the roll-out method and the slit-down method, but in either method, the thin sheet is obtained directly from molten glass, and the thinner the wall, the more likely it is that warping, bending, and wrinkles will occur, resulting in problems with processing accuracy and efficiency. The disadvantage is that it is bad.

The present invention was proposed to improve these drawbacks, and involves gripping the upper part of the glass base plate and lowering it at a constant speed.
The original glass plate is passed through a heating furnace with a temperature gradient in the width direction so that the central part is heated to the highest temperature, and the original glass plate is heated gradually from the bottom to the top to a softened state, and then heated downward. The gist of this method is to stretch thin sheets and cut them into predetermined lengths, making it possible to mass-produce thin glass sheets with high machining accuracy at a speed two to three times faster than conventional methods.

That is, the first feature of the present invention is to heat the original glass plate with a temperature gradient in the width direction so that the central part of the glass plate reaches the highest temperature, thereby softening the glass plate.

By setting such heating conditions, it was possible to prevent local thickening of the end portion of the thin glass plate and dramatically improve processing accuracy.

The second feature is the realization of an industrial mass production device that can efficiently produce high-quality thin plates from glass base plates.

According to the present invention, the glass base plate softened by the heating device is held between the endless belts and forcibly pulled downward, but by the time the endless belts are used to hold the glass plate, the temperature has already reached a point where the glass plate is not deformed. Since the thin glass plate does not touch the device during the deformation period when it is in a softened state, a smooth surface is obtained without wrinkles.

If the base glass plate is simply heated and stretched, the edges tend to become thicker and the width of the plate tends to shrink slightly.

In the present invention, a thin glass plate having a uniform thickness is obtained by heating the base glass plate with a temperature gradient in the width direction so that the temperature at the center portion is the highest.

These features will become clearer from the following description of the embodiments.

As shown in the drawings, in the present invention, a base board supply device a, a heating device and a root pulling device C are arranged in tandem.

Each driving device provided in C is controlled so that arbitrary root pulling conditions can be obtained.

The original plate supply device a has a machine base 1 and a machine head 2 connected and fixed at a predetermined interval by a support 3 to form a machine frame.

A ball screw 5 with a slide base 4 screwed thereon is inserted between the base 1 and the head 2 along this support 3.

The lower end of the screw 5 is supported by a bearing 6 of the base 1, and the upper end projects through a bearing 7 of the head 2, and a gear 10 of a drive motor 9 is engaged with a gear 8 fixed to the projecting upper end.

Reference numeral 11 indicates a brake device for the motor 9.

By rotating the drive of the motor 9 in the forward or reverse direction, the screw 5
The slide base 4, which is screwed together with the base plate 7, moves up and down at a predetermined speed while its rotation is restricted along the fixed plate 7.

The slide table 4 is also integrally provided with a chuck arm 13 for gripping the glass base plate 12, and has an air cylinder 15 at its tip for opening and closing the chuck 14.

Next, the heating device will be explained. As shown in FIG. 1, this device is fixed to the machine base 1, installed directly below the chuck 13, and has a slit in the center that passes through the hanging base plate 12. .

As is clear from the plan view of FIG. 2A, the heating elements, such as electric heaters, provided on both sides facing the base plate 12 passing through the slit 16 of the heating device are
It is divided into blocks of Arashi 5', each of which is individually set to a temperature distribution similar to the one shown in the figure.

A guide roller 17 guides the vertically descending base plate 12 to the upper opening of the slit 16.

At the bottom of this heating device is a tension mechanism part d of the softening base plate 12.
A root pulling device C having a cutting mechanism section e and a cutting mechanism section e are arranged in a column.

The tension mechanism part d includes two sliding plates 20 and 2 that move left and right by piston movements of left and right cylinders 18 and 19.
1, driven rollers 22 and 23 attached to each of the sliding plates 20 and 21, drive rollers 24 and 25, between the driven roller 22 and the drive roller 24, and the driven roller 2
3 and the endless belt 26 hung between the drive roller 25
．． 27, a group of tension rollers 28, which are inserted into the slit 16 of the heating device between the belts 26 and 27 moving at a higher speed than the supply speed of the original plate, and sandwich the softened original plate 12' that has fallen down in a softened state. engulf it.

The distance between the heating device and the driven rollers 22 and 23 is
Since the softening base plate 12' must be cooled to a temperature at which it no longer deforms even if it is held between rollers, the distance should be increased as the plucking speed becomes faster.

The cutting mechanism part e is a sliding plate 2 equipped with the tension mechanism part d.
A cutter 29 is provided at 0.21 mm and cuts a cutting line in the glass thin plate obtained by redrawing and cooling the softened original plate 12'.
and a cut-off device 29' whose blade protrudes and presses the cutting line using an air cylinder.

30° 31 indicates a cutting guide roller, and 32.33 indicates an auxiliary roller.

The heating device according to the present invention described above controls the heating elements individually for each block and heats the central part of the glass base plate to a higher temperature than the edges, so that the glass base plate has a small width. Since a thin glass plate with high flatness can be obtained even if the method is used, there is no need for the process of trimming the edges and removing thick portions.

In this way, the present invention grips a glass base plate, feeds it downward at a constant speed, gradually heats it from the bottom to the top while creating a temperature gradient in the width direction, and then thinly stretches it downward to a predetermined length. The various drive mechanisms described above are automatically controlled by a sequence program, and mass-produces products that are quick, accurate, and extremely uniform.

[Brief explanation of drawings]

The drawings show an embodiment for explaining the present invention, in which Fig. 1 is a partially cutaway front view, Fig. 2 is a plan view and temperature distribution diagram of the heating device, and Fig. 3 is a front view of the pipe pulling device. It is a diagram. a is the base plate supply device, b is the heating device, C is the tube pulling device, d is the tension mechanism section, e is the cutting mechanism section, 4 is the slide plate, 12
is the original glass plate.

Claims (1)

[Claims] 1. A step of grasping the glass base plate and sending it downward, and creating a temperature gradient in the width direction so that the central part of the glass base plate reaches the highest temperature, and softening it from the bottom to the top. A method for manufacturing a thin plate by stretching a glass base plate, which comprises the steps of heating, forcibly stretching the softened glass base plate downward, and cutting the stretched glass thin plate into a predetermined length. 2. A base plate feeding device that grips the upper part of the glass base plate and feeds it downward, and a base plate supply device located below the base plate at a fixed position on both sides facing the base plate,
A heating device heats the base plate to a softened state from the bottom to the top with a temperature gradient in the width direction so that the temperature is highest at the center, and a heating device that heats the base plate to a softened state from the bottom to the top so that the temperature is highest in the center, and a heating device that heats the base plate to a softened state from the bottom to the top, and An apparatus for manufacturing a thin plate by stretching a glass base plate, which is comprised of a pulling mechanism for stretching the thin plate and a cutting mechanism for cutting the thin plate pulled down into a predetermined length.