JP2003012334A - Method for bending glass thin plate and working device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for bending a strip-form glass thin plate in a direction perpendicular to the thickness direction, capable of obtaining extremely high dimensional precision of the bent part, especially extremely high planarity of both surfaces of the bent part, and a working device therefor. SOLUTION: This bending device 1 comprises holding blocks 2 and 3 for freely slidably holding a strip-form glass thin plate 10, a heating part 4 for heating to melt the glass thin plate 10, a sliding mechanism 5 for sliding the glass thin plate 10 to the length direction, and a turning arm 24 for turning the one of holding block 3 to the predetermined direction. The glass thin plate 10 is bent with the heating part 4 as a center of bending while being slid by the sliding mechanism 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending a belt-shaped thin glass plate in a direction orthogonal to its thickness direction, and an apparatus therefor.

[0002]

2. Description of the Related Art Generally, a thin glass plate is used as a gap plate of a magnetic head or a spacer of electronic parts. Further, a rectangular frame-shaped thin glass plate having four corners, such as a pair of glass spacers, is known. This frame-shaped glass thin plate is formed by bending an elongated strip-shaped glass thin plate at four points in a direction orthogonal to its thickness direction.

For example, when such a rectangular frame-shaped glass thin plate is used as a spacer, and two rectangular plate-shaped members having the same size as the spacer are bonded to each other to make a vacuum inside, the glass thin plate as the spacer is used. Requires high dimensional accuracy. That is, when the inside is evacuated, the airtightness between the spacer and the two plate-shaped members on both sides becomes important,
The flatness of both surfaces of the spacer is important.

[0004]

However, in general, when a band-shaped thin glass plate is melted and is bent at a substantially right angle in the direction orthogonal to the thickness direction, the radius of curvature on the outer side of the bent portion and the radius of curvature on the inner side are bent. Because it is different, the thin glass plate outside the bent part is stretched and the wall thickness becomes thin,
As a result, a glass pool is formed inside the bent portion, and the wall thickness increases. Further, in this case, it is conceivable that the radius of curvature outside the bent portion becomes large. Further, depending on the bending method, the bent portion may be cracked or wrinkled. As described above, when the difference in thickness between the inside and the outside or the formation of cracks or wrinkles is caused in the bent portion of the thin glass plate, the difference in thickness when used as a spacer requiring airtightness as described above. , Cracks, wrinkles, etc. cause serious problems such as impairing airtightness.

The present invention has been made in view of the above points, and an object thereof is to make the dimensional accuracy of a bent portion extremely high when bending a band-shaped glass thin plate in a direction orthogonal to its thickness direction, In particular, a method of bending a thin glass plate capable of extremely improving the flatness of both sides of the bent portion,
And to provide a processing device therefor.

[0006]

In order to achieve the above object, a method for bending a glass thin plate of the present invention is a method for bending a straight strip-shaped glass thin plate in a direction orthogonal to its thickness direction. A holding step of slidably holding the glass thin plate on both sides along the longitudinal direction of the bent portion, a heating step of heating the glass thin plate in the bending portion to melt it to a bendable degree, and a holding step in the holding step And a bending step of bending the glass thin plate having its bent portion heated in the heating step at the bent portion while moving in the longitudinal direction thereof.

According to the above invention, the belt-shaped thin glass plate slidably held is heated at its bending portion to be in a bendable state, and is bent at the bending portion while moving in the longitudinal direction. Thereby, the dimensional accuracy such as the width, the wall thickness, and the radius of curvature of the bent portion can be increased, and in particular, the flatness of both surfaces of the bent portion can be increased.

The glass thin plate bending apparatus of the present invention is a device for bending a straight belt-shaped glass thin plate in a direction orthogonal to its thickness direction, and the glass thin plate is slidable along its longitudinal direction. And a first holding part for holding the thin glass plate slidably along the longitudinal direction of the first holding part at a position spaced from the first holding part, and the first holding part. And a second holding portion, the heating portion that heats the glass thin plate by melting so as to be bendable, and the glass thin plate held by the first and second holding portions in the longitudinal direction thereof. A slide mechanism for sliding, and the second holding portion is rotated in a predetermined direction around the heating portion in conjunction with the sliding operation by the slide mechanism, and the glass thin plate is bent around the heating portion. It is provided with a structure, a.

According to the above invention, the belt-shaped glass thin plate slidably held by the first and second holding parts is heated and melted by the heating part to such a degree that it can be bent, and the glass thin plate is slid in the longitudinal direction by the sliding mechanism. Meanwhile, the bending mechanism rotates the second holding portion to bend the thin glass plate about the heating portion. As a result, dimensional accuracy such as width, wall thickness, and radius of curvature of the bent portion of the thin glass plate can be increased, and in particular, flatness of both surfaces of the bent portion can be increased.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing the structure of a main part of a bending apparatus 1 (hereinafter simply referred to as a processing apparatus 1) according to an embodiment of the present invention. This processing device 1
The thin strip-shaped glass thin plate 10 is bent substantially at right angles in the direction orthogonal to the thickness direction. Further, FIG. 2 shows a schematic configuration of the pinching mechanism 8 for finishing the bent portion.

As shown in FIG. 1, a processing apparatus 1 includes holding blocks 2 and 3 for holding a glass thin plate 10 slidably at two positions along its longitudinal direction, and the glass thin plate 10 is held between the holding blocks 2 and 3. Heating part 4 for heating, thin glass plate 10
It has a slide mechanism 5 that slides in the longitudinal direction, and a bending mechanism 6 that bends the thin glass plate 10 by rotating one holding block 3 around the heating unit 4. In addition to this, the processing apparatus 1 has a clamping mechanism 8 shown in FIG.
The thin glass plate 10 is slid in the arrow T direction in the figure by the slide mechanism 5, and is bent in the arrow B direction in the figure by the bending mechanism 6.

One holding block 2 (first holding portion) arranged upstream of the glass sheet 10 in the sliding direction (direction of arrow T) has a slide groove 11 into which the glass sheet 10 is slidably fitted. The depth of the slide groove 11 is
The thickness of the glass thin plate 10 is set to be the same, and the width of the slide groove 11 is set to be the same as the width of the glass thin plate 10. Two feed rollers 12 and 13 functioning as a slide mechanism 5 for sliding the glass thin plate 10 fitted in the slide groove 11 in the direction of the arrow T are provided at positions facing the slide groove 11.

In the other holding block 3 (second holding portion) arranged on the downstream side of the glass thin plate 10 in the sliding direction,
A slide groove 14 is formed so that the thin glass plate 10 can be slidably fitted in the direction of arrow T. This slide groove 1
The depth and width of 4 are also set to be the same as the thickness and width of the glass thin plate 10. In the non-operating state, these two slide grooves 11 and 14 are aligned in the longitudinal direction of the glass thin plate 10. A plate-shaped cover member 15 for pressing the thin glass plate 10 fitted in the slide groove 14 is fixed to the holding block 3 by a screw 16 at a position facing the slide groove 14.

A heating unit 4 is fixedly arranged on the holding block 3. As shown in detail in FIG. 3, the heating unit 4 includes a pair of substantially rectangular block-shaped ceramic plates 17 and 18.
Have. Each ceramic plate 17 (18) is formed by stacking a cover 17b (18b) on the back side of a pressing plate 17a (18a) containing a heater wire 19. Each of the ceramic plates 17 and 18, and particularly the pressing plates 17a and 18a, is formed of, for example, a fluorophlogopite-based crystal-containing porous ceramics that does not easily adhere to the heat-melted glass thin plate. In addition, the pressing plates 17a and 18a have flat surfaces having a sufficient width for bending the thin glass plate 10.

The pair of ceramic plates 17 and 18 formed in this way are arranged at positions where the surfaces of the pressing plates 17a and 18a are in contact with both surfaces of the glass thin plate 10. Then, one ceramic plate 18 is attached to the support portion 22 via a spring 21 and is urged toward the other ceramic plate 17. That is, in the structure shown in FIG.
Glass thin plate 10 held by two holding blocks 2 and 3
The pressing surfaces of the pair of ceramic plates 17 and 18 are brought into face-to-face contact with both surfaces of and pressed.

However, a pair of ceramic plates 17, 18
Does not necessarily have to be biased to press the thin glass plate 10 and may be fixed via a certain gap. In this case, the gap between the pair of ceramic plates 17 and 18 is set to be the same as the thickness of the glass thin plate 10.

Further, the holding block 3 includes the support rod 2
It is connected to the tip of the rotating arm 24 via 3. At the base end of the rotating arm 24, a rotary shaft 24a connected to a motor described later is provided. The rotary shaft 24a is provided coaxially with a rotary shaft (not shown) that passes through the center of the heating unit 4. That is, the holding block 3 is attached so as to rotate about a rotation shaft (not shown) of the heating unit 4, and the one end 23a of the support rod 23 is fixedly provided on the rotation tip side. The rotation axis (not shown) of the holding block 3 is set at a position extending in the thickness direction on the center line of the thin glass plate 10 held by the two holding blocks 2 and 3.

The pinching mechanism 8 shown in FIG.
This is for instantaneously pressing the bent portion of the glass plate from the thickness direction to increase the flatness of the surface of the glass thin plate 10 (FIG. 2b). In addition, the pressing mechanism 8 presses the glass thin plate 10 bent at four places in a state where both ends of the glass thin plate 10 are overlapped, and the glass thin plate 1
It is intended to connect both ends of 0 (Fig. 2c). In the present embodiment, the pinching mechanism 8 is provided separately from the structure of FIG. 1, but the pair of ceramic plates 17 of the heating unit 4,
It is also possible to use 18 together.

The pinching mechanism 8 has a pair of pinching arms 31, 32 extending substantially in parallel. Each pinching arm 31 (32)
Is a pinch pad 31c (32c) made of stainless steel or cast iron via an L-shaped support portion 31b (32b) bent at an axial direction at the tip of the rotary shaft 31a (32a).
Is equipped with. Rotating shaft 31 of each pinching arm 31 (32)
Gears 33 and 34 are attached in the middle of a (32a) so as to mesh with each other. That is, by rotating the one rotation shaft 31a (32a), the other rotation shaft 32a (31a) is rotated in the opposite direction by the same rotation amount.

Two clamping pads 31c, 3 of the clamping mechanism 8
2c is arranged at a position where the pressing surfaces 31d (32d) are separated from each other when set in the state shown in FIG. 2 (a), and is rotated to the position shown in FIG. 2 (b) or 2 (c). In this case, the pressing surfaces 31d and 32d are set to face each other with a predetermined gap therebetween. At this time, the gap between the two pressing surfaces 31d and 32d is set to be the same as the thickness of the glass thin plate 10.

FIG. 4 shows a block diagram of a control system for controlling the operation of the processing apparatus 1 configured as described above.

The control system of the processing apparatus 1 has a control section 40 for controlling the operation of the processing apparatus 1 according to the operation program stored in the memory 41. The control unit 40 includes a motor 42 for rotating the two feed rollers 12 and 13 of the slide mechanism 5 in a predetermined direction at a predetermined peripheral speed, and a rotating arm 24 of the bending mechanism 6 for rotating in a predetermined direction. Motor 4
3, a motor 44 for rotating the gear 33 (34) attached to one rotating shaft 31a (32a) of the pinching mechanism 8 in both forward and reverse directions, and built in the pair of ceramic plates 17 and 18 of the heating unit 4. A heater switch 45 for switching on / off the energization of the heater wire is connected.

Next, the processing apparatus 1 configured as described above.
The bending operation by the above will be described mainly with reference to the flowchart of FIG. 5 and the operation explanatory diagram of FIG.

First, the glass thin plate 10 as a processing material is fitted and set in the slide grooves 11 and 14 of the two holding blocks 2 and 3 which are separated from each other (step 1). The glass thin plate 10 is prepared in advance by a manufacturing method such as a redrawing method to have a predetermined plate thickness and plate width, and is set in the processing device 1 so that the planned bending position is located at the center of the heating unit 4. It At this time, the glass thin plate 10 is inserted from one end side thereof between the slide groove 11 of the holding block 2 and the two feed rollers 12 and 13, and is inserted between the pair of ceramic plates 17 and 18 of the heating unit 4, and the other side. Is fitted into the slide groove 14 of the holding block 3. After that, the cover member 15 is attached to the holding block 3 with the screw 16.

Then, the heater switch 45 is turned on to energize the heater wires 19 contained in the pair of ceramic plates 17 and 18 of the heating section 4, and the ceramic plates 17 and 18 are heated to a predetermined temperature (step 2). At this time, the portion to be bent of the glass thin plate 10 located in the heating portion 4 is heated and melted to be softened to the extent that viscous flow occurs.

Next, the motor 42 of the slide mechanism 5 is driven to rotate the feed rollers 12 and 13 in a predetermined direction at a predetermined speed, so that the glass thin plate 10 held by the two holding blocks 2 and 3 extends in the longitudinal direction ( It is slid in FIG. 1; arrow T direction). At the same time, the motor 43 of the bending mechanism 6 is driven to rotate the holding block 3 in a predetermined direction (direction of arrow B in FIG. 1) about the heating unit 4, and the glass thin plate 10 is bent. At this time, the holding block 3 and the pair of ceramic plates 17 and 18 of the heating unit 4 are also rotated from the state shown in FIG. 6A to the state shown in FIG. 6B. That is, while the glass thin plate 10 is slid by the slide mechanism 5,
The thin glass plate 10 is bent by the bending mechanism 6 (step 3).

If the thin glass plate 10 is bent without sliding in the longitudinal direction, the thickness becomes thinner outside the bent portion and becomes thicker inside the bent portion. As a result, the difference in wall thickness between the outside and the inside of the bent portion becomes large. If the thin glass plate 10 is bent without sliding,
The bent part may be wrinkled or cracked. However, if the sliding amount of the glass thin plate 10 is made larger than the plate width, the curvature shape of the bent portion may be deformed. Therefore, in the present embodiment, the glass thin plate 10 is bent at a right angle while the glass thin plate 10 is slid by the maximum length equal to the plate width.

The thin glass plate 10 bent in this way
The bent part has a high dimensional accuracy such as a constant plate width, a constant radius of curvature, and a constant plate thickness, but the maximum difference between the thickness outside the bend and the thickness inside the bend is about 0.3 mm. Has occurred. For example, when the glass thin plate 10 is used as a rectangular frame-shaped spacer interposed between two plate-shaped members and the inside is evacuated, the glass thin plate 10 is required to have a further dimensional accuracy. Thickness difference 0.1mm
Must be kept within.

In order to increase the flatness of the bent portion, in the present embodiment, immediately after the thin glass plate 10 is bent at a right angle in step 3, before the bent portion is cooled, the pinching mechanism 8 is used to move the bent portion. The pressure was instantaneously pinched at least once to equalize the wall thickness inside and outside the bent portion (step 4) (FIG. 2b). At this time, the glass thin plate 10
The bent portion of (1) needs to have a sufficiently low viscosity so that viscous flow can be easily generated, and thus is reheated as necessary.

When the pressing surfaces 31d, 32d of the pressing pads 31c, 32c of the pressing mechanism 8 are brought into contact with the bent portion of the thin glass plate 10 for a long time, the heat of the bent portion causes the heat of the bent pad 3 to come into contact.
It escapes via 1c and 32c, and the bent portion is rapidly cooled and solidified. Therefore, in the present embodiment, the pressing surfaces 31d and 32d of the pressing pads 31c and 32c are momentarily brought into contact with the bent portions of the thin glass plate 10,
The heat is prevented from escaping from the bent portion.

As a result, it is possible to prevent the bent portion from being cooled below the strain point, to prevent cracks from being generated by thermal shock, and to prevent glass from adhering to the pressing surfaces 31d and 32d. It should be noted that in order to perform sufficient flat surface processing, the pressing surfaces 31d and 32d are subjected to the glass thin plate 1 several times.
It may be brought into contact with 0 instantaneously, and the bent portion may be reheated several times during the process.

After the processes of steps 3 and 4 are repeated a predetermined number of times, here four times (step 5; YE
S), a thin glass plate 1 bent in four places in a rectangular frame shape
Both ends of 0 are slightly overlapped and connected (step 6). At this time, both ends of the laminated glass thin plates 10 are heated and melted to the extent that viscous flow is generated, and the pressing mechanism 8 is pressed.
As a result, as shown in FIG. 2C, the pressure is instantaneously applied from both sides. Clamping pads 31c and 32c of the clamping mechanism 8
2C is rotated to the state shown in FIG. 2C, the gap between the pressing surfaces 31d and 32d of the pressing pads 31c and 32c is set to be the same as the thickness of the thin glass plate 10. The pressure pad 3 is provided on both ends of which 10 are overlapped.
The plate thickness of the connecting portion is made the same as the plate thickness of the other portion of the glass thin plate 10 by instantaneously pressing with 1c and 32c.
Also in this case, in order to further enhance the flatness of the connecting portion of the glass thin plate 10, the connecting portion may be reheated as necessary, and the connecting portion is pressed by the pressing mechanism 8 a plurality of times. May be.

By the above operation, the rectangular frame-shaped glass thin plate 100 as shown in FIG. 6C is manufactured. The thin glass plate 100 has high dimensional accuracy at the four bent portions and at the connecting portions at both ends, and particularly has a uniform plate thickness over the entire length of the thin glass plate 100. For this reason, when the frame-shaped thin glass plate 100 is used as a spacer that draws a vacuum between two plate-shaped members, high airtightness can be maintained.

FIG. 7 shows a modification of the heating section 4 described above.

When the flat pressing surfaces of the pressing plates 17a and 18a of the respective ceramic plates 17 and 18 are brought into contact with both surfaces of the glass thin plate 10 which is slid and moved, as in the heating section 4 described above, they are sufficiently melted. Softened glass sheet 10
There is a case where a sufficient sliding effect does not occur between the surface of the glass sheet and the pressing surface, and the curvature shape of the glass thin plate 10 is deformed.

In order to prevent such a problem, in the modification shown in FIG. 7, the pressing faces of the pressing plates 51a, 52a of the ceramic plates 51, 52 on the side contacting the glass thin plate 10 are arranged along the glass thin plate 10. The unevenness is formed, one ceramic plate 51 is fixedly arranged, and the other ceramic plate 52 is rotated.

That is, on the pressing surface of the pressing plate 51a of the one ceramic plate 51 fixedly arranged, the projection 53 having a curvature shape matching the curvature shape inside the bent portion of the glass thin plate 10 is provided. Between the glass thin plate 10
The slide groove 54 that fits in is formed. And the protrusion 5
A hole 53a is formed in the center of curvature of No. 3 to pass the rotation axis. Further, similar to the above-described embodiment, a heater wire (not shown) is built in the pressing plate 51a, and the cover 51 is provided on the back side thereof.
attached b.

On the other hand, the outer surface of the glass thin plate 10 is pressed against the pressing surface of the pressing plate 52a of the other ceramic plate 52 movably arranged with respect to the ceramic plate 51 when the glass thin plate 10 is bent. The slender projection 55 is provided, and the slide groove 56 that fits the thin glass plate 10 between the projection 55 and the projection 55 is formed. Then, the corner A ′ of the pressing plate 52a is made to coincide with the corner A of the pressing plate 51a, and the pressing plate 52a
When the corner B'of a is aligned with the corner B of the pressing plate 51a, a hole 56a coaxial with the hole 53a of the pressing plate 51a is also formed in the pressing plate 52a. Further, a heater wire (not shown) is also incorporated in the pressing plate 52a, and the cover 5 is provided on the back side thereof.
2b was attached.

Then, the holes 53 of the pressing plates 51a and 52a are formed.
Attach a rotary shaft (not shown) to a and 56a, and slide groove 5
A pair of ceramic plates 51 and 52 are combined so that the pressing surfaces face each other, and the movable ceramic plate 52 is rotatable together with the holding block 3, and the fixed ceramic plate 51. Was not driven by the rotation of the holding block 3.

The glass sheet 1 is heated by the heating unit 50 having the above-mentioned structure.
When 0 is heated and melted and bent, first, the slide grooves 54 and 56 of the linear ceramic plates 51 and 52 are formed.
Then, the glass thin plate 10 is fitted. Then, the movable side ceramic plate 52 is rotated by 90 ° about the rotation shaft (hole 56a) as the holding block 3 is rotated. At this time, the protrusion 53 formed on the pressing surface of the fixed ceramic plate 51.
So that the curved inner side of the glass thin plate 10 follows the curvature shape of
Further, the glass thin plate 10 is bent at a right angle so that the curved outer side of the glass thin plate 10 is pressed by the protrusion 55 formed on the pressing surface of the movable ceramic plate 52.

According to this modification, the pair of ceramic plates 5 are
A sufficient sliding effect can be produced between the pressing surfaces of the glass sheets 1 and 52 and the glass thin plate 10, and the curvature shape of the bent portion of the glass thin plate 10 can be stabilized both inside and outside thereof. The dimensional accuracy such as the curvature shape can be further improved.

Next, an embodiment of the present invention will be described with reference to the graph of FIG.

In order to find out the optimum slide amount (feeding moving distance in the graph) of the glass thin plate 10 which can maximize the dimensional accuracy of the bent portion when the glass thin plate 10 is bent at right angles in the direction orthogonal to the thickness direction, The following experiment was conducted.

First, the plate width 10.00 ± 0.05 [mm],
A glass thin plate 10 having a plate thickness of 1.00 ± 0.05 [mm], which does not include surface defects such as streaks, bubbles, and stone bumps, and has high flatness with less warpage and undulation is manufactured by the redraw method. Is set in the processing apparatus 1 of the present invention. And
According to the processing method of the present invention, while changing the sliding amount of the glass thin plate 10 within the range of 0 to 1.4 times the plate width, the plate thickness on the inner side of the curved portion of the bent portion (inner curved portion wall thickness in the graph), bending The plate thickness of the curved outside of the portion (thickness of the outer curved portion in the graph) and the plate width of the bent portion were examined.

The results are shown in the graph of FIG. As is clear from the graph, when the thin glass plate 10 is bent at a right angle without sliding and moving (feeding moving distance is zero), the thickness of the bent portion is 1.10 [m
m], 0.60 [mm] on the outside of the curve, the difference in plate thickness inside and outside the curve is as large as 0.50 [mm], and the plate width of the bent part is also reduced to 7.00 [mm]. Understand. Further, it was found that when the sliding amount of the glass thin plate 10 was made larger than the plate width, the curvature shape of the bent portion was deformed beyond the allowable amount, which was not preferable.

That is, in order to increase the dimensional accuracy of the bent portion of the thin glass plate 10 to the required accuracy of the present invention, the sliding amount of the thin glass plate 10 is set within the range of 0.2 times to 1.0 times the plate width. Just set it. If the slide amount is set within this range, the difference between the inside and outside of the bending of the bending pressure of the bending portion is within 0.3 [mm], the plate width is 9.0 [mm] or more, and the curvature shape of the bending portion is stable. Things have been obtained.

In the present embodiment, the most preferable slide amount is 6.0 [mm], the inner thickness of the bent portion is 1.20 [mm], and the outer thickness is 1.0 [mm]. The inside-outside difference is extremely small at 0.2 [mm], and the width of the bent part is 1
With 0 [mm], there was almost no change, and a bending process with an extremely high dimensional accuracy with a radius of curvature of 5.0 [mm] inside the bent portion and a radius of curvature of 15.0 [mm] outside was realized.

When the sliding amount of the thin glass plate 10 is set within the above range (0.2 times to 1.0 times the plate width), as described above, the thickness of the inside of the bent portion and the thickness of the outside thereof are The maximum difference is 0.3 [mm], but when a bending process with a smaller plate thickness difference and higher dimensional accuracy is required, the clamping mechanism 8 described above causes It suffices to perform processing and momentarily press the bent portion. In this embodiment, when the bending portion was subjected to the secondary processing by the pressing mechanism 8, the difference in plate thickness between the inside and outside of the bending portion was 0.
It could be corrected within 1 [mm].

In addition to the above-described embodiment, the heating unit 4
When the conditions of (1) were set as follows, good results could be obtained in terms of dimensional accuracy of the bent portion.

That is, a pair of ceramic plates 17, 18 made of fluorophlogopite-based crystal-containing porous ceramics,
A nichrome wire heater having a diameter of 0.4 [mm] was built in, and the heating part 4 was operated at 210 [W] (voltage 30 V, current 7 A). Then, when the glass thin plate 10 was slid within the range of the above-described embodiment and the glass thin plate 10 was bent at a right angle by the processing method of the present invention, the difference between the plate thickness inside the bent portion and the plate thickness outside thereof was maximized. It was possible to set within 0.1 [mm].

Further, as a modified example of the heating unit 4 described above, when the above-mentioned setting conditions of the heating unit 4 are adopted in the heating unit 50 described in FIG. 7, the difference in plate thickness between the inside and the outside of the bent portion can be extremely reduced. Needless to say, the curvature shape of the bent portion can be extremely stabilized both inside and outside, and bending processing with almost no fluctuation in processing size was realized.

The present invention is not limited to the above-described embodiments, but can be variously modified within the scope of the present invention.

[0054]

As described above, according to the method for bending a glass thin plate of the present invention and the processing apparatus therefor, when bending a strip-shaped glass thin plate in a direction orthogonal to its thickness direction, The dimensional accuracy can be made extremely high, and especially the flatness of both surfaces of the bent portion can be made extremely high.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a configuration of a main part of a bending apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the clamping mechanism of the processing device.

FIG. 3 is a view for explaining the structure of a heating unit of a processing device.

FIG. 4 is a block diagram showing a control system that controls the operation of the processing apparatus.

FIG. 5 is a flowchart for explaining a bending operation by the processing device.

FIG. 6 is an operation explanatory view for explaining a bending operation by the processing device.

FIG. 7 is a diagram showing a modification of the heating unit.

FIG. 8 is a graph for explaining an example of the present invention.

[Explanation of symbols]

1 ... Bending device 2, 3 ... Holding block, 4, 50 ... Heating section, 5 ... Slide mechanism, 6 ... Bending mechanism, 8 ... Clamping mechanism, 10 ... thin glass plate, 11, 14 ... slide groove, 12, 13 ... Feed rollers, 15 ... Cover member, 17, 18, 51, 52 ... Ceramic plate, 19: heater wire, 24 ... Pivoting arm, 31c, 32c ... pinching pad, 31d, 32d ... clamping surface, 40 ... control unit, 42, 43, 44 ... Motors.

Claims (12)

[Claims] 1. A method of bending a straight belt-shaped glass thin plate in a direction orthogonal to its thickness direction, which comprises a holding step of slidably holding the glass thin plate on both sides along the longitudinal direction of the bent portion. A heating step of heating the glass thin plate at the bending portion to melt it so that it can be bent, and moving the glass thin plate held in the holding step and heated at the bending portion in the heating step in the longitudinal direction thereof. And a bending step of bending at the bending portion while allowing the glass sheet to bend. 2. The pressing step of causing a pair of flat pressing surfaces to momentarily press-contact from both sides in the thickness direction of the bent portion bent in the bending step. A method for bending a glass thin plate as described. 3. In the bending step, the glass thin plate is
The method for bending a thin glass sheet according to claim 1 or 2, wherein the glass sheet is bent at a substantially right angle while being moved in the longitudinal direction by a distance longer than ⅕ of the sheet width and shorter than the sheet width. 4. A method according to claim 3, wherein one glass thin plate is bent substantially at right angles in the same direction at four points along its longitudinal direction, and both ends of the glass thin plate are overlapped in the thickness direction thereof.
A processing method characterized in that a frame-shaped thin glass plate is formed by heating, melting and connecting the portions. 5. A reheating step of heating the bent portion bent in the bending step again so that the bent portion is melted to a bendable degree, and a pair of flat plates from both sides in the thickness direction of the reheated bent portion. The method for bending a thin glass sheet according to claim 1, further comprising a pressing step of pressing and pressing the pressing surfaces instantaneously. 6. The method for bending a thin glass plate according to claim 5, wherein the reheating step and the pinching step are repeated a plurality of times. 7. In the bending step, the glass thin plate is
The method for bending a thin glass plate according to claim 5 or 6, wherein the glass thin plate is bent at a substantially right angle while being moved in the longitudinal direction by a distance longer than ⅕ of the plate width and shorter than the plate width. 8. A method according to claim 7, wherein one glass thin plate is bent substantially at right angles in the same direction at four locations along its longitudinal direction, and both ends of the glass thin plate are overlapped in the thickness direction thereof.
A processing method characterized in that a frame-shaped thin glass plate is formed by heating, melting and connecting the portions. 9. A device for bending a straight belt-shaped glass thin plate in a direction orthogonal to its thickness direction, the first holding portion holding the glass thin plate slidably along its longitudinal direction. A second holding part that holds the thin glass plate slidably along the longitudinal direction at a position separated from the first holding part, and the above-mentioned between the first holding part and the second holding part. A heating unit that heats and melts the glass thin plate to a bendable extent, a slide mechanism that slides the glass thin plate held by the first and second holding units in the longitudinal direction, and a slide by the slide mechanism. Interlocking with the operation, the second holding portion is rotated in a predetermined direction around the heating portion,
A bending mechanism for bending the thin glass plate around the heating unit, and a bending device for the thin glass plate. 10. The bending mechanism bends the glass sheet at a substantially right angle while the glass sheet is slid in the longitudinal direction by a distance longer than ⅕ of the sheet width and shorter than the sheet width by the slide mechanism. The apparatus for bending a thin glass plate according to claim 9, wherein: 11. A clamping mechanism for momentarily pressing and contacting a pair of flat clamping surfaces from both sides in the thickness direction of the bent portion of the glass thin plate bent by the bending mechanism. Item 9. A bending apparatus for a glass thin plate according to Item 9 or 10. 12. The apparatus for bending a glass thin plate according to claim 9, wherein the heating unit has a pair of ceramic plates that have a built-in heater and are in contact with each other from both sides in the thickness direction of the glass thin plate.