JPS59156925A - Glass sheet bending device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device as defined in the generic form of claim 1 for bending a glass sheet heated to a softening temperature.

Devices for bending a glass sheet heated to a softening temperature are known from German Patent Nos. 1,679,961 and 2,331,584, in which a bending rod is used in a plane defined by the surface of the shape of the bend; Each rod rotates around an axis connecting both ends of the rod, thereby deforming the plastic glass plate according to the shape of the rod. The bending force is obtained by pressing the glass plate against an opposing die or opposing rollers having a similar shape to the die rod. A disadvantage of this device is that there are problems maintaining accurate curve formation lines. In other words, when a flat glass plate is fed onto a mold rod that is curved along a horizontal conveying plane, but turned into a horizontal slow plane, the glass plate is asymmetrical with respect to the conveying direction axis. , different lateral forces occur on both sides of the longitudinal axis. Therefore, the glass plate is likely to shift laterally, and as a result, the angle between the intended curve forming axis and the actual curve forming axis that coincides with the sheet feeding direction may not be O.

Another disadvantage is that when the curved rod is pivoted upward,
Since the glass plate is guided only by its center, it can no longer maintain a stable posture. Another problem that degrades optical quality, especially in the case of thin glass sheets, is the recess in the surface contact area, where strong heat exchange causes local variations in the cooling of the glass sheet, and the use of curved opposing rollers. In some cases, there is also the so-called opposed roller effect, which causes transverse waves to occur in glass sheets that are particularly thin and have low bending resistance, making it difficult to manufacture optically superior curved glass sheets.

In the device of German Publication No. 2621902, a glass plate runs over a mold rod which is curved in the form of a non-upward convex surface, with the degree of curvature of the curve forming line gradually increasing in the passing direction. The shape of the heated and softened glass plate follows the curved shape of the rod under the action of gravity. A significant drawback of this device is that the curve formation line is not precisely fixed. The more irregular the shape given to the glass plate, the more difficult it becomes to maintain the desired precise curve. For example, in the case of a Chi A-shaped glass plate, different gravitational effects are applied to the partial areas that are given different shapes on each side of the curve formation axis, and the curve formation does not progress consistently, so it is almost impossible to solve the problem. Possible difficulties arise.

A device for bending a glass sheet heated to a softening temperature in this manner is also known from German Patent No. 2,532,318, in which a mold plate is formed from six parts and a rotatable driven cylinder, for example a sleeve. To convey a glass sheet that is still flat, the curved rod is pivoted into a horizontal position so that a horizontal conveying plane is formed. When starting the bending process, the curved rod is pivoted downward.

The actual bending process is carried out by raising the entire system together with the mold rod and pressing it against the opposing mold. The main advantage of this known device is the precise positioning of the glass pane, but the disadvantage is that the glass pane must remain stationary while the actual bending operation takes place, making continuous movement impossible. In addition, in this device, the glass plate, which is still flat, must be conveyed by passing it over a curved rod that has been turned to a horizontal plane, which is different from other known devices in which the glass plate is likely to shift laterally during conveyance. Related problems arise that have already been mentioned.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an apparatus for bending a glass plate heated to the softening temperature in which the above-mentioned problems do not occur.

In particular, we propose an apparatus that can correctly guide a glass plate that is still flat, and can evenly bend even an extremely thin glass plate without deteriorating its optical properties.

This object is achieved in the present invention by the features described in claim 1.

Preferred embodiments are described in the following claims.

The advantages achieved with the invention are based on the following operational aspects.

The glass sheet, which has been heated to a softening temperature from the furnace and is in a plastically deformable but still flat shape, is conveyed by a plurality of linear conveyor rods to the actual deforming section. In this deformation processing section, mold rods curved directly downward are fixed between the individual conveyor rods. When the transported glass sheet reaches the deformation station, first of all the pressing means, which can consist, for example, of a pressing roller with a pressure cylinder, are lowered from above onto the surface of the glass sheet. Since this pressure roller is located directly above a single straight conveyor rod, it is impossible for bending moments to occur that could cause transverse wave deformation in delicate glass or plates.

The linear conveyor rod is also lowered in synchronization with this lowering of the suppression means. This operation can be carried out, for example, by starting the lowering of the conveyor rod at the moment when the suppression roller comes into contact with the surface of the glass sheet. The conveyor rod descends to a deforming operation position corresponding to the position of the fixed mold rod which is curved directly downward. As a result, the plastic glass plate is deformed into a desired curved shape.

During this series of operations, the glass plate is transported as it is, and in this case, since the curved rod is accurately oriented in the direction of the glass, any relative movement between the rod outer cylinder and the glass plate is avoided. Therefore, the curvature of the mold rod must match the desired shape of the plate to be applied. However, this is an extremely preferable configuration in terms of the optical quality of the curved glass plate. That is, no relative movement occurs at all, which causes distortion, which may be slight but cannot be overlooked optically.

To make it easier to replace the convex rod according to the desired curved shape of the glass plate, the mold rod can be mounted on an independent machine frame that can be easily replaced from the side by pulling it out along the rail. be.

Generally, the suppression roller is allowed to rotate freely. That is, when it comes into contact with the glass plate, it is caused to be rotated by the glass plate. However, in the case of extremely thin and delicate glass plates, it is preferable to drive the suppression roller in accordance with the feed speed of the glass plate, in order to avoid any relative movement here as well.

If the entire bending process is performed without changing the feed speed of the glass plate, the time the glass plate passes over the original deformed part is extremely short, so the amount of heat dissipated is very small. This has the advantage of being able to enter the prestress introduction section on the downstream side at almost the same temperature as when it exited the furnace installed in Because it comes into contact with the glass plate only,
There is very little heat exchange with the high temperature glass surface. This contributes to maintaining the glass pane at the required high temperature.

When the glass sheet curved by the curved rod is conveyed away from the deformation section, the straight conveyor rod in the deformation section is very quickly raised into the conveying operating position, for example under the action of a compressed air cylinder; The next glass plate can enter the deformation section.

The advantage of using mostly fixed type curved rods is that, rather than having to adjust individual mold rods, the mold rods can simply be replaced as a whole assembly as the curvature changes to be applied to the glass pane. good.

Known devices, in which the mold rods had to be swiveled individually, required complicated adjustments and were often not able to be adjusted with the required accuracy, resulting in wavy deformations in the curved glass pane. . This problem is solved by the simple construction of the present invention.

The feeding speed of the flat glass plate when leaving the furnace is higher than the passing speed inside the furnace, so that the glass plate passes through the deformation processing section at a relatively high speed, and the number of curved rods used is relatively small. The glass plate in a plastic state sinks into the gap between the mold rollers.
It is preferable to allow very little time to do so.

In order to produce high-quality curved prestressed glass sheets, it is necessary to provide a prestressing introduction section downstream of the deformation process where the curved glass sheets are rapidly cooled by applying a gas flow, generally a nitrogen flow. . A prestressing introduction device designed for passing a glass plate between conveyor rods placed one above the other is known from German Publication No. 2 213 670. However, this conveyor rod prevents the flow of the gas flow on both sides of the glass plate, especially the escape of the gas flow, making it impossible to obtain the desired quenching effect. Furthermore, although this known device can generate the necessary stagnation pressure cushion in the rod area, it does not take into account that the heat transfer is impeded by these same rods. Therefore, extremely high gas flow driving energies must be used to achieve the desired heat transfer. When such a prestress introducing section is used to treat a relatively thick glass plate, the above-mentioned drawbacks are not so much of a problem, but when using a thin glass plate, for example, only 3 mm thick,
In the case of side window glass for automobiles, treatment is only possible by significantly increasing the total nitrogen flow rate. However, as the speed increases, the pressure generated on the surface (support) of the glass plate increases at a rate of two, and especially in the case of a thin glass plate, the surface deforms frequently and the optical quality deteriorates beyond the permissible limit.

To avoid such problems, 1. In the prestress introducing section provided on the downstream side of the deformation processing section, a nozzle lip is placed between the curved rods on the lower side of the glass plate, and a nozzle lip is placed above the glass plate to match the curvature of the glass plate so as to accurately face this nozzle rib. Install a shaped nozzle lip. A throttle is incorporated in the back area between the upper nozzle lip to increase the pressure level above the glass plate without creating an extra stagnation area that adversely affects heat transfer. This throttle prevents the glass plate from lifting as a result of the increase in downward positive pressure, and can reduce the necessary pressing force on the glass plate.

By appropriately selecting the diameter and distribution of the holes in the upper and lower nozzle ribs, it is possible to ensure uniform heat conduction on both sides of the glass plate even if there are differences in the flow conditions of the gas flow.

As an alternative to this embodiment, a curved condensing rod may be integrated into the downward blowing system and configured to utilize the Coanda effect to guide the gas flow along the conveyor rod and tangentially impinge on the curved glass pane. Good too. With this configuration, the conveyor rod and mold rod, which were obstacles to the ventilation system in the conventional prestress introducing section, can be used to guide the gas flow, and the gas flow can be controlled to achieve a rapid cooling effect. The effect can be improved.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings.

As is clear from FIG. 1, a flat glass plate 1 heated to a softening temperature by a furnace (not shown) is moved to its original deformed portion 4 by a linear conveyor rod 3 constituting a roller conveyor 2'fr as a whole. Transport to. Straight conveyor rods 3 are also arranged in the deformation processing section 4. One curved mold rod 5 is interposed between two adjacent conveyor rods 3 (FIG. 3), and this mold rod 5 is curved to match the curvature to be given to the glass plate 11. is located below the straight conveyor rod 3, as can be seen from the apex line 8 in FIG.

When the glass plate 1 is completely conveyed to the deformation processing section 4, the suppression roller 6 descends to the upper surface of the glass plate 1. This pressure roller 6 is actuated by a pressure cylinder 6' which generates a precise pressure force.

The suppression roller 6 and the pressure cylinder 6' are mounted on a gallows-like machine frame 2 which is connected to the support structure of the conveyor rod 3 in the deformation section 4. A machine frame 2 and a pressing roller 6,
The linear conveyor rods 3 in the deformation section 4 can be vertically lowered together.

When the freely rotatable suppression roller 6 aligned in the feeding direction of the glass plate 1 comes into contact with the upper surface of the glass plate 1 that has completely reached the deformation section 4, the upper contact plane 7 of the straight conveyor rod 3 becomes curved. The suppression row 26 and the linear conveyor rod 3 in the deformation section 4 descend until they coincide with the apex line 8 of the rod 5. Since the pressing roller 6 is located directly above the linear conveyor rod 3, no moment is applied to the bend by the pressing row 26.

During the above process, the glass plate 1 is sent as it is in the direction of the arrow and passes through the deformation processing section 4.
The desired curvature can be given by the cooperation of the mold rod 5 and the mold rod 5.

The curved rod 5 is fixed to a machine frame 20 that can be replaced by pulling it out laterally on a rail 21. Such replacement work becomes necessary, for example, when it is desired to manufacture several different glass plates. This is because the curvature of the vertically downwardly curved mold rod must match the curvature desired to be imparted to the glass sheet to be manufactured.

The conveyor rod 3 and the mold rod 5 have a known construction. That is, six parts are surrounded by a rotatable driven outer cylinder. This outer cylinder may be, for example, a sleeve molded to fit part 6, but 19. Multiple rings may be fitted around the six parts.

FIG. 3 schematically shows the driving of the curved rod 5 by the electric motor M via the chain K.

The curved glass plate 1 is carried away from the deformation processing section 4 by the rotation of the outer cylinder of the curved rod 5 and reaches a prestress introduction section n1 to be described later. Next, the linear conveyor rod 3 in the deforming section is raised again to the conveying operation position by a compressed air cylinder (not shown), and the next glass plate 1 is ready to enter the deforming section 4.

FIG. 4 is a cross-sectional view of a prestress introduction section disposed downstream of the deformation processing section 4. As shown in FIG. The curved glass plate 1 is guided in the braceless introduction by a curved rod 5, which here acts as a conveying means. Curved type) 5
In the gap between them, a nozzle rib 10 is arranged below a curved glass plate 16. This lower nozzle lip 1
0, a similar upper nozzle rib 9 is arranged above the curved glass plate 16 passing through the prestress introduction part in the direction of the arrow. The nozzle lips 9 and 10 are configured to match the uneven shape of the glass plate, and send not only an airflow perpendicular to the glass plate but also an airflow in an oblique direction.

A throttle 11 is incorporated in the back area between the upper nozzle lips 9 to increase the pressure level above the glass plate 16 without creating stagnation zones that would adversely affect heat transfer.

This throttle prevents the glass plate 16 from lifting due to the increase in positive pressure below the glass plate 16, and thereby enables the glass plate 16 to be pressed against the curved rod 5 with a slight pressing force from above. .

By appropriately selecting the nozzle diameter and hole distribution, the upper nozzle lip 9 can be replaced with the lower nozzle lip 10 so that even if the flow state on the upper side of the glass plate 16 is uneven, uniform heat conduction can be obtained as in the lower side. can be synchronized with.

FIG. 5 shows another embodiment of the prestressing introduction part, in which the curved rod 5 is integrated with the ventilation system below the glass plate 16. As schematically illustrated in Figure 5, the Coanda effect (
A gas flow is made to flow along the curved rod 5 of circular cross-section using a gas flow tangentially to the curved glass plate 16 as required to achieve a favorable heat transfer. . That is, the gas flow does not directly hit the surface of the glass plate, which means that the curved glass plate 1
This is important for the optical properties of 6.

In this embodiment, since the upper nozzle rib 9 is located directly above the center line of the curved rod 5, the force of the gas flow does not exert a bending moment on the curved glass plate. In order to
For example, the mold rod may be surrounded from both sides by a )-shaped jet stream.

As an alternative to the embodiment described above, the rotatable outer cylinder of the die opening and door 5 may be constructed of a ring 14, as shown in FIG. A curved annular groove 15 is formed between the rings 14, and the air supply nozzle 1 is arranged below the mold rod 5.
7, air is blown out and all the annular grooves 1 of each mold rod 5
5 or in the same direction through the annular groove 1 of each mold rod 5
Air is blown in different directions every 5 times. In the area of contact between the glass plate 16 and the mold rod 5, this air flow passes through the glass plate 16 at high speed to achieve the necessary heat transfer.

In order to deform the glass plates and introduce prestress, the feeding speed of the glass plates 1 and 16 when leaving the furnace is higher than the passing speed in the furnace. It is necessary to reduce the time for "sinking" in the gap between the conveyor rods 3, and to prevent the glass plate surface from becoming distorted or crabbed.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the deformation processing section with the linear conveyor rod in its original conveying position, and Fig. 2 is a longitudinal sectional view of the deformation processing section with the linear conveyor rod lowered to the deformation action position. 3 is a cross-sectional view of the deformed section, FIG. 4 is a first embodiment of the prestress introducing section located downstream of the deformed section 710, and FIG. 5 is the downstream section of the deformed section. A second embodiment of the prestress introducing portion disposed on the side, FIG. 6 is a sloped view showing a modification of the embodiment shown in FIG. 5. 1...Flat glass plate, 2...Machine frame, 3...Conveyor rod, 4...Deformed processing section, (End...Curved rod)'
, 6...pressure roller, 6'...pressure cylinder, 7.
...Upper contact surface of conveyor rod, 8...Vertex line of front curved rod, 9°10.12...Nozzle rib, 11...
・Throttle, 14...Ring, 15...Ring gap, 16...Curved glass 7°
Margin below FIG, 6 Procedural amendment (method) % formula % 1. Indication of the case 1982 Patent Application No. 27842 2. Name of the invention Glass plate bending processing device 3. Person making the amendment Relationship to the case Name of the patent applicant ＝Name 07 ``-'''''' (9bl)・ 4. Agent address: Shizuko Toranomon Building, 101'5 Toranomon-8-chome, Minato-ku, Tokyo 105 Tel: (504) 0721 Name: Akira Aomizu, Patent Attorney (6579) , j6, Subject of amendment (1) Power of attorney (2) Drawing 7, Contents of amendment ill As attached (2) Engraving of drawing (no change in content) 8, List of attached documents

Claims (1)

[Scope of Claims] 1. a) a plurality of conveyor rods that convey a flat glass plate while forming a horizontal surface as a whole; b) being curved to match the shape of the glass plate after being curved;
a plurality of mold rods disposed in the deformation processing section, and C) a suppressing means for pressing the glass plate against the mold rods, d) a softening temperature comprising a conveyor rod and a mold rod in six parts and a rotatable driven outer cylinder. In a bending device that bends a heated glass plate, e) a straight conveyor rod (
3) can move up and down between the upper conveying position and the lower deformation working position, and f) a fixed mold rod (5) curved directly below.
is located at a height corresponding to the deformation processing position of the conveyor rod (3), and g) the suppressing means (6, 6') pushes the glass plate (1) from above in synchronization with the descent of the conveyor rod (3). A glass plate bending processing device characterized by being pressed into contact with a glass plate. 2. The apparatus according to claim 1, wherein the suppressing means is comprised of a pressure cylinder (6') and a suppressing roller (6) arranged in a direction perpendicular to the glass plate feeding direction. 3. Device according to claim 2, characterized in that the suppression roller (6) is located above the linear conveyor rod (3). 4. The device according to claim 2 or 3, characterized in that the pressing force generated from the pressure cylinder (6) can be adjusted. 5. The suppression means (6, 6') contact the flat glass plate (1) as soon as the conveyor rod (3) descends, and are lowered together with the conveyor rod (3) to the deformation processing angle position. An apparatus according to any one of claims 1 to 4 characterized in the above. 6. Device according to claim 5, characterized in that the suppression means (6, 6') are raised before the passage of the trailing edge of the glass plate (1). 7. Pressure cylinder (6') together with pressure roller (6),
The device according to any one of claims 2 to 6, characterized in that it is supported by a vertically movable gallows-like machine frame (2) 4C. 8. Device according to any one of claims 2 to 7, characterized in that the suppression roller (6) is freely rotatable. 9. The device according to any one of claims 2 to 7, characterized in that the suppression roller (6) is rotationally driven in accordance with the feeding speed of the glass plate (1). 10- Conveyor rod (3) in deformation working position
10. Device according to claim 1, characterized in that the upper tangent surface of the curved rod (5) coincides with the apex line (8) of the curved rod (5). il, conveyor rod (3
11. Device according to claim 1, characterized in that the mold rods (5) and mold rods (5) are arranged alternately. 12. A nozzle rib (1o) formed to match the shape of the curved glass plate (16) is arranged between the curved rods (5) behind the deformed part (4) when viewed in the feeding direction, 12. Device according to claim 1, characterized in that the gas flow is applied from the nozzle ribs to the curved glass plate (16) in a direction perpendicular and in an oblique direction. 13. A curved rod (5) is integrated into the nozzle rib (12) behind the deformed part (4) when viewed in the feed direction, and the mold rod (5) is removed from the nozzle rib (12) using the Coanda effect. 12. Device according to claim 1, characterized in that the gas flow is guided along the outer surface of the curved glass plate (16). 14 The outer cylinder of the type rod (5) was composed of a plurality of rings (14) arranged back and forth in the axial direction, so that the gas flow passed through the gap (15) between the rings (14). 14. The device according to claim 13, characterized in that: +5.4 Lower nozzle 1J above the curved glass plate (16)
Any one of claims 12 to 14, characterized in that another nozzle rib (9) configured to match the shape of the glass plate is arranged opposite to f (10, 12). The device described in. 16. The device according to claim 15, characterized in that the throttle means (11)' is provided between nozzle ribs provided above the curved glass plate (16). 17. Claim 1, characterized in that the feeding speed of the glass plate (1) when leaving the furnace and when passing through the deformation processing section is higher than the feeding speed when passing through the furnace. to any one of paragraphs 16 to 16.