JP3988009B2 - Method and apparatus for bending glass plate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for bending a glass plate for transportation equipment such as automobiles, ships, railways, and aircraft, or for various other uses for construction.
[0002]
[Prior art]
Conventionally, a method of bending a glass sheet by conveying the glass sheet heated to near the softening point in a heating furnace with a roller conveyor composed of a plurality of curved rollers is known (for example, US Pat. No. 4,123, No. 246). In this method, since the softened glass plate hangs down by its own weight, the glass plate is bent so as to follow the curvature of the roller.
[0003]
Further, a method of bending a glass plate by conveying a glass plate heated to near the softening point in a heating furnace with a plurality of rollers that are inclined in the conveying direction so that the conveying path is curved is known. (For example, U.S. Pat. No. 4,820,327). According to this method, since the softened glass plate hangs down by its own weight, the glass plate is bent so as to follow the curvature of the conveyance path.
[0004]
In the present specification, “bend-formed in a direction perpendicular to the conveyance direction” means that the shape of the bent glass plate is curved around the axis in the conveyance direction. In other words, the bent glass plate has a curved cross section perpendicular to the conveyance direction axis. Similarly, “bend-formed along (in the conveying direction)” means that the shape of the bent glass plate is curved around an axis perpendicular to the conveying direction. In other words, the bent glass sheet has a curved cross section perpendicular to the axis perpendicular to the conveying direction. Regarding the shape of the curved surface formed by a plurality of rollers shown below, explanations such as “curved in the conveying direction (along)” and “curved in the conveying direction” are “bently molded in (along) the conveying direction”. This means the same. The description of the curved surface in the direction orthogonal to the conveyance direction is also the same as the meaning of “bending in the direction orthogonal to the conveyance direction”.
[0005]
In this specification, “... perpendicular to the direction” means a direction on the horizontal plane and perpendicular to the direction. In the present specification, “upper” and “lower” mean “upper” and “lower” with respect to the horizontal plane, respectively.
[0006]
[Problems to be solved by the invention]
By the way, in the recent automobile industry, the demand for a small variety of products is increasing, and therefore glass plates having a curvature corresponding to each type are required. For this reason, in the method described in the above-mentioned U.S. Pat. No. 4,123,246, it is necessary to replace the roller with a curvature corresponding to the model for each model. This replacement takes time, and it is necessary to prepare a roller having a curvature required for each model.
[0007]
In this case, the glass plate is transported in a direction perpendicular to the bending direction. In this case, for example, in bending the side glass plate for automobiles, the side direction in the state of attachment to the automobile is the extending direction of the rollers. The attached state is a state in which roller distortion due to contact of the roller with the glass plate is conspicuous.
[0008]
In the method described in U.S. Pat. No. 4,820,327, it is necessary to change the arrangement of the rollers so that the conveyance path has a curvature corresponding to the model for each model. This change was time consuming.
[0009]
In the method '327, the conveyance direction of the glass plate is changed to the vertical direction. Therefore, the entire equipment used for the method of '327 becomes large. Moreover, since the glass plate is conveyed against the gravity, it is difficult to convey the glass plate at a high speed, and a structure for preventing the glass plate from sliding on the roller must be specially provided. Furthermore, the glass plate after being bent and tempered by air cooling must change the transport direction from the vertical direction to the horizontal direction. The mechanism for changing the conveying direction is complicated, and there is a concern about the occurrence of scratches on the glass plate.
[0010]
An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to provide a novel glass plate bending method and apparatus that have not been known so far.
[0011]
[Means for Solving the Problems]
  The present invention has been made in view of the above problems,The glass plate is heated to a molding temperature in a heating furnace, and the heated glass plate is conveyed along a conveying surface formed by a plurality of rollers of a roller conveyor, and the glass plate is bent to a predetermined curvature by its own weight. In a method of bending a glass plate to be formed, a plurality of rollers at a position where the glass plate is conveyed are moved up and down along with the conveyance of the glass plate, and glass is applied to at least a part of the conveying surface by the plurality of rollers at the position While forming a desired curved surface curved in the conveyance direction of the plate, the rollers are sequentially moved up and down along with the conveyance of the glass plate to advance the curved surface in the conveyance direction of the glass plate along with the conveyance of the glass plate, The present invention provides a glass plate bending method characterized by bending a glass plate along the curved surface while conveying the glass plate.
[0014]
Furthermore, the present invention is a glass plate bending method including a heating furnace for heating the glass plate to a bending temperature, and a forming means for bending the glass plate provided on the downstream side of the heating furnace to a predetermined curvature. In the apparatus, the forming means includes a roller conveyor composed of a plurality of rollers forming a conveying surface for conveying the glass plate, a vertical driving means for moving the plurality of rollers up and down, and a glass plate being conveyed. A plurality of rollers at a position form a desired curved surface curved in the conveyance direction of the glass plate on at least a part of the conveyance surface, and the plurality of rollers are sequentially moved up and down as the glass plate is conveyed. And a control means for controlling the drive means so that the curved surface advances in the conveying direction of the glass sheet, and a glass sheet bending apparatus comprising: .
[0015]
Specifically, each roller itself moves up and down in the vertical direction as the glass plate is conveyed. By this vertical movement, a curved surface is formed by a plurality of rollers at positions where the glass plate is conveyed, and this curved surface advances in the conveying direction of the glass plate. In other words, the curved surface corresponds to a wavefront, each roller corresponds to a wave vibrator, and the vertical stroke length of each roller corresponds to an amplitude. And a wave is propagated by giving a phase difference to the up-and-down movement of each roller so that the phase of each vibrator changes sequentially toward the conveyance direction, and the curved surface advances in the conveyance direction of the glass plate.
[0016]
As for the vertical movement of each roller, it is preferable that the movement returning from the initial position in the vertical direction to the initial position through descending and rising is one cycle of movement. In this case, each roller (a; initial state) starts when the front side in the conveyance direction of one unit of glass plate is conveyed, and (b) while one unit of glass plate passes. The movement is one cycle of descent-rise. (C; final state) When the rear side in the conveyance direction of one unit of the glass plate has been conveyed, it returns to the original position. Thus, while a unit of glass plate passes over a roller, the roller moves up and down in one cycle from the initial state to the final state. When bending a plurality of glass plates continuously, one unit of the glass plate is sequentially conveyed, so that each roller is moved to (a), (b), (c ) Repeatedly move up and down in this order.
[0017]
By such vertical movement of each roller, one unit of glass plate is conveyed as follows. When the glass plate is positioned on a roller having a front side in the transport direction and a rear side in the transport direction, the roller is in an initial state (final state). For this reason, the vertical positions of the front side and the rear side of the glass plate in the transport direction are maintained at the initial positions of the rollers. A virtual surface formed by each roller in the initial state is referred to as a “transport level”. On the other hand, each roller in which the center part of the glass plate which is a part between the conveyance direction front side of a glass plate and a conveyance direction rear side is located exists in the intermediate state of the vertical movement of 1 period. Therefore, the central part of the glass plate is located below the transport level (the central part hangs down). Accordingly, one unit of the glass plate is transported such that the central portion is positioned below the transport level while the transport direction front side and the transport direction rear side are maintained at the transport level.
[0018]
Note that “one unit glass plate” usually means one glass plate. When transported in a state where two or more glass plates are laminated as required, two or more glass plates can be bent at the same time. Thus, “one unit glass plate” includes a case where two or more glass plates are conveyed in a stacked state. And the bending method and apparatus of the glass plate of this invention can bend-mold a 1 unit glass plate sequentially continuously, and can bend and shape a multiple unit glass plate continuously. Whether a single unit glass plate is a single glass plate or a state in which a plurality of glass plates are laminated does not significantly affect the basic operation of the glass plate bending method and apparatus of the present invention. . Therefore, in this specification, the word “1 unit” can be omitted.
[0019]
According to the present invention, the plurality of rollers are moved up and down in accordance with the conveyance position of the glass plate to curve the conveyance surface formed by the plurality of rollers, and the glass plate is caused by its own weight along the curved conveyance surface. Bending to a predetermined curvature. Thereby, since a glass plate can be bent and formed without using a plurality of rollers having a curvature corresponding to the model, it is possible to omit the conventionally required roller replacement operation. Further, according to the present invention, another type of glass plate can be formed simply by changing the vertical movement control data of the roller, so that the job change time can be substantially eliminated.
[0020]
The curved surface formed by each roller has the following meaning. First, the center axis of each roller is assumed. Since each central axis extends in a direction perpendicular to the transport direction, a virtual curved surface is formed by smoothly connecting each central axis. This virtual curved surface corresponds to the curved surface formed by each roller. Actually, since each roller has a finite thickness, the curved surface formed by each roller is slightly different from the virtual curved surface. That is, the radius of curvature of the curved surface formed by each roller is slightly smaller (about the radius of the roller) than the radius of curvature of the virtual curved surface. Therefore, the curved surface formed by each roller corresponds to a curved surface having a slightly smaller radius of curvature than the virtual curved surface.
[0021]
And the desired curved surface formed by each roller is a curved surface required according to the position where the glass plate is conveyed on the roller. Specifically, at the most downstream position in the zone where the glass sheet is bent, the curved surface formed by each roller at this position is the glass sheet to be finally obtained in the conveying direction of the glass sheet. It exhibits a curved shape that roughly matches the bent shape.
[0022]
As one example, the curved surface formed by each roller located upstream from the most downstream position has a larger radius of curvature than the curved surface formed by each roller at the most downstream position. As it goes further upstream, the curved surface formed by each roller at the upstream position has a larger radius of curvature.
[0023]
As another example, at all positions in the zone where the glass plate is bent, the curved surface formed by each roller is made to have a curved shape that roughly matches the bent shape in the conveyance direction of the glass plate to be finally obtained. You can also In any case, in order to bend the glass plate into the bent shape of the glass plate to be finally obtained, the curved surface formed by each roller is determined according to the position where the glass plate is conveyed. It is a curved surface. At this time, the curved shape is determined in consideration of the thickness of the glass plate and the temperature of the glass plate, and how to change the shape of the curved surface according to each of these conditions (or a certain curved shape) It is preferable to configure the apparatus so that it can be set appropriately.
[0024]
Glass plates often do not bend instantaneously due to their own weight. Therefore, the curvature radius of the curved surface formed by each roller is gradually reduced from the upstream side, and the curved shape of the glass plate to be finally obtained at the most downstream position can be made to convey each roller. It is preferable in view of the point that the driving force can be sufficiently transmitted to the glass plate.
[0025]
By the way, when a roller moves up and down, the conveyance speed of the horizontal direction component of a glass plate will depend on the up-and-down position of a roller. In this case, when the angular velocities of the plurality of rollers are constant, the conveyance speed of the horizontal component is higher for the lower roller than for the upper roller. When such an unbalance phenomenon of speed occurs, slip occurs between the roller and the glass plate, and the glass plate is easily damaged.
[0026]
Therefore, it is preferable to provide rotation driving means for independently rotating the plurality of rollers, and to control the rotation driving means so that the conveying speed of the horizontal component of the glass plate is equalized by the control device. Thereby, generation | occurrence | production of the said slip can be prevented and a glass plate without a damage | wound can be obtained.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a glass sheet bending method and apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.
[0028]
FIG. 1 is a perspective view showing the structure of a glass sheet bending apparatus 10 according to an embodiment of the present invention. The molding apparatus 10 shown in the figure is mainly composed of a heating furnace 12, a molding zone 14, and an air cooling strengthening apparatus 16.
[0029]
First, the bending process of the glass plate 18 by the molding apparatus 10 will be described. The glass plate 18 before bending is positioned at the entrance of the heating furnace 12 and then transported into the heating furnace 12 by a roller conveyor (not shown). The glass plate 18 is heated by the heater of the heating furnace 12 during conveyance in the heating furnace 12, and is heated to the bending temperature (about 600 to 700 ° C.) at the outlet of the heating furnace 12. The glass plate 18 heated to the temperature is conveyed to the forming zone 14 installed on the downstream side of the heating furnace 12 by a roller conveyor 20 for bending. The glass plate 18 is bent to a predetermined curvature by a bending operation by the roller conveyor 20 during conveyance in the forming zone 14. The bent glass plate 18 is conveyed from the exit of the forming zone 14 to the air-cooling strengthening device 16 by the roller conveyor 22 for the air-cooling strengthening device 16 and is air-cooled and strengthened here. The air-cooling strengthening device 16 includes an upper air outlet head 24 and a lower air outlet head 26 that are disposed with a roller conveyor 22 interposed therebetween, and the glass plate 18 blows out from the air outlet heads 24 and 26 toward the glass plate 18. Air cooling is enhanced by the air that is generated. At this time, the cooling capacity of the air-cooling strengthening device 16 is appropriately set according to the thickness of the glass plate 18. The glass plate 18 that has been air-cooled and tempered is conveyed from the outlet of the air-cooling and tempering device 16 toward the inspection device (not shown) in the next process by the roller conveyor 28. The above is the flow of the molding process of one glass plate 18 by the molding apparatus 10.
[0030]
Next, the roller conveyor 20 in the molding zone 14 will be described with reference to FIGS. The roller conveyor 20 is composed of a plurality of rollers (13 rollers 20A to 20M (see FIG. 2) in the present embodiment) formed in a straight shape arranged in a horizontal state in parallel with each other in the conveying direction of the glass plate. The glass plate 18 is conveyed by the rotation of the rollers 20A to 20M along the conveying surface formed between the rollers 20A to 20M.
[0031]
Each of the rollers 20A to 20M is independently rotationally driven by the rotational driving means, and is independently vertically moved by the vertical driving means. The rotation driving means and the vertical driving means are controlled by a motion controller.
[0032]
FIG. 4 is a structural diagram showing the rotation driving means and the vertical driving means of each of the rollers 20A to 20M. Since the rotation driving means and the vertical driving means of each of the rollers 20A to 20M have the same structure, FIG. 4 illustrates only the structure on the roller 20A side for convenience, and the other rollers 20B to 20M side. The description of the structure is omitted.
[0033]
Both ends of the roller 20A are rotatably supported by bearings 32 and 32 on a moving frame 30 formed in a concave shape. Further, the spindle 40 of the servo motor 38 is connected to the left end of the roller 20A in FIG. By driving the servo motor 38, the roller 20A is rotated at a predetermined angular velocity. The above is the structure of the rotation driving means.
[0034]
On the other hand, both sides of the moving frame 30 are supported by the fixed frame 42 via an LM (linear motion) guide so as to be movable up and down. In the LM guide, a guide rail 44 is arranged in the vertical direction on the moving frame 30 side, and a guide block 46 on the fixed frame 42 side is engaged with the guide rail 44.
[0035]
Further, racks 48, 48 project downward from both ends of the lower part of the moving frame 30, and pinions 50, 50 are engaged with the racks 48, 48. The pinions 50 and 50 are fixed to a rotating shaft 52 disposed in the horizontal direction. The rotating shaft 52 is supported at both ends by bearings 54 and 54, and the left end in FIG. 4 is a spindle 58 of a servo motor 56. It is connected to. Thus, when the rotary shaft 52 is rotated by the servo motor 56, the rotary motion is converted into a linear motion by the action of the pinion 50 and the rack 48, so that the moving frame 30, that is, the roller 20A is moved up and down. The above is the structure of the vertical driving means. Note that reference numerals 60 and 62 in FIG. 4 denote heaters provided in the molding zone 14.
[0036]
The rotation driving means and the vertical driving means described above are provided in all the other rollers 20B to 20M, and the servo motors 38 and 56 of these means are controlled by a motion controller.
[0037]
The motion controller will be described. When the model of the glass plate 18 is input from the external input means, the motion controller receives angular velocity control data and vertical movement control data of the rollers 20A to 20M corresponding to the curvature of the glass plate 18 of that type. Create The motion controller controls the servo motor 38 based on the created angular velocity control data and controls the servo motor 56 based on the vertical movement control data. That is, the motion controller multi-axially controls the rollers 20A to 20M so that the glass plate 18 is bent and formed to a desired curvature during conveyance by the rollers 20A to 20M.
[0038]
Next, a multi-axis control method of the rollers 20A to 20M by the motion controller will be described with reference to FIG. The basic up-and-down movement of the roller is one that moves down and up sequentially in the order of the rollers 20A → 20M as the glass plate is conveyed. In addition, the code | symbol in () in the following description respond | corresponds to the code | symbol in () in FIG.
[0039]
For example, when the heated glass plate 18 reaches the inlet side roller 20A, all the rollers 20A to 20M are at the uppermost position (A). The conveyance surface formed between 20A to 20M is horizontal (corresponding to FIG. 3A). When the glass plate 18 is further conveyed, the rollers 20B and 20C descend.
[0040]
Next, when the glass plate 18 is transported, the rollers 20D to 20F move downward, and among the transport surfaces formed between the rollers 20A to 20M, a transport surface formed between the rollers 20D to 20F. It is deformed into a convex curved shape with a large curvature radius (B). As a result, when the glass plate 18 passes over the rollers 20D to 20F, the glass plate 18 bends downward along the curved surfaces of the rollers 20D to 20F by its own weight, and deforms into a shape along the curved surface ( Corresponding to FIG.
[0041]
By the way, when the rollers 20D to 20F move downward, the conveyance speed Vx of the horizontal component of the glass plate 18 depends on the vertical positions of the rollers 20D to 20F. In this case, when the angular speed (rotational speed) ω of the rollers 20D to 20F is constant, the transport speed Vx of the horizontal component is higher in the lower roller 20E than in the upper rollers 20D and F. When such a speed unbalance phenomenon occurs, slip occurs between the rollers 20D to 20F and the glass plate 18, and the glass plate 18 is easily damaged.
[0042]
Therefore, the motion controller controls the servo motors 56 of the rollers 20D to 20F so that the conveyance speed Vx of the horizontal component of the glass plate 18 by the rollers 20D to 20F becomes equal (see FIG. 5). That is, the motion controller uses the vertical position of the rollers 20D to 20F as a parameter and the angular velocity of the rollers 20D to 20F is ω._D> Ω_E<Ω_FControl to be Thereby, since the said malfunction is eliminated, the glass plate 18 is not damaged by slip.
[0043]
When the glass plate 18 is further transported, the rollers 20F to 20H move downward more than the previous rollers 20D to 20F, and the transport surface formed between the rollers 20F to 20H becomes the front surface. The curved surface is deformed into a curved shape having a smaller radius of curvature (larger bending) (C). As a result, when the glass plate 18 passes over the rollers 20F to 20H, the glass plate 18 is further bent downward along the curved surfaces of the rollers 20F to 20H and deformed into a shape along the curved surface (FIG. 3C). Corresponding). In addition, since the glass plate 18 is continuously conveyed, between the state of FIG. 3 (B) and the state of FIG. 3 (C), the roller 20D and the roller 20E are more than the state of FIG. 3 (B). It is above and is located below the state of FIG.
[0044]
When the glass plate 18 is positioned approximately in the middle of the conveyance path, the rollers 20H to 20J move downward more than the rollers 20F to 20H, and the conveyance surface is formed between the rollers 20H to 20J. However, it deform | transforms into the curved shape whose curvature radius is smaller than the previous curved surface (D). Thus, when the glass plate 18 passes over the rollers 20H to 20J, the glass plate 18 is further bent downward along the curved surfaces of the rollers 20H to 20J, and deformed into a shape along the curved surface (FIG. 3D). Corresponding).
[0045]
Finally, when the glass plate 18 is positioned downstream of the conveyance path, the rollers 20J to 20L move downward more than the rollers 20H to 20J, and the conveyance is formed between the rollers 20J to 20L. The surface is deformed into a curved shape having a curvature corresponding to the curvature of the glass plate 18 to be finally obtained (E). As a result, when the glass plate 18 passes over the rollers 20J to 20L, the glass plate 18 is deformed into a shape along the curved surface thereof, so that it is bent to a desired curvature (corresponding to FIG. 3E). The above is the bending operation of the glass plate 18 by the rollers 20A to 20M.
[0046]
Therefore, each roller in the forming zone 14 moves down and ascends in one cycle as the glass plate 18 passes when the glass plate 18 is conveyed. Thereby, a convex wavefront is formed by the group of rollers on which the glass plate 18 is positioned, and this wavefront is advanced along with the conveyance of the glass plate 18. The front side and the rear side in the transport direction of the glass plate 18 are kept at the transport level, and the central portion of the glass plate 18 hangs down below the transport level according to the lowered position of each roller. Thus, the glass plate 18 is bent and formed in the conveyance direction while being conveyed by each roller. In this case, since the front side and the rear side in the transport direction of the glass plate 18 are kept at the transport level, the transport direction of the glass plate can be said to be a direction parallel to the transport level.
[0047]
In addition, since the glass plate 18 is bent greatly as it goes downstream of the forming zone 14, the amplitude of the wavefront is larger toward the downstream. That is, the amplitude due to the descending / raising motion of each roller is larger toward the downstream of the forming zone 14.
[0048]
By the way, the glass sheet bending method and the bending apparatus in the present invention are used for bending a large number of glass plates. That is, a large number of glass plates are bent and formed by successively conveying a plurality of glass plates one by one. Therefore, each roller of the forming zone 14 repeats vertical vibration in order to bend and form the glass plates that are sequentially conveyed. Therefore, a plurality of downwardly convex waves proceed sequentially from the heating furnace 12 toward the air-cooling strengthening device 16 in the molding zone 14.
[0049]
And the amplitude of a wave increases as it goes to the air-cooling strengthening apparatus 16 from the heating furnace 12 side.
[0050]
As described above, according to the present embodiment, the straight rollers 20A to 20M are used as the plurality of rollers, and these rollers 20A to 20M are moved up and down in conjunction with the conveyance of the glass plate 18 to move the glass plate 18 to each other. As a result of bending the roller, it is possible to omit the roller replacement work that was conventionally necessary. Further, another type of glass plate can be formed simply by changing the vertical movement control data of the roller, so that the job change time can be substantially eliminated. Furthermore, according to the present embodiment, since the air cooling strengthening device 16 is provided on the downstream side of the forming zone 14, the air cooling strengthening device 16 is tempered by rapidly cooling the glass sheet after bending. A bent glass plate 18 can be obtained.
[0051]
By the way, in said embodiment, since the conveyance surface formed between roller 20A-20M is curved by the curved surface which has a single curvature radius, the glass plate 18 bent-shaped also has a single curvature. It is bent into a curved surface having a radius. On the other hand, as will be described below, the conveying surface formed between the rollers 20 </ b> A to 20 </ b> M is curved into a curved surface having a plurality of curvature radii, whereby the glass plate 18 is conveyed in a conveying direction having a plurality of curvature radii. It can be bent into a curved surface. In the following embodiment, a case where a curved glass plate 18 in which a curved surface having a curvature radius R1 and a curved surface having a curvature radius R2 are combined will be described with reference to FIG. In this description, the reference numerals in parentheses correspond to the reference numerals in parentheses in FIG.
[0052]
At the stage where the heated glass plate 18 reaches the roller 20A on the entrance side, all the rollers 20A to 20M are at the uppermost position, and the conveyance surface formed between the rollers 20A to 20M is horizontal ( A). And if the glass plate 18 is conveyed in the shaping | molding zone 14, a roller will descend | fall sequentially and the conveyance surface formed between roller 20C-20G will deform | transform into a gentle curve (B). As a result, when the glass plate 18 passes over the rollers 20C to 20G, the glass plate 18 bends downward along the curved surface of the rollers 20C to 20G due to its own weight, and deforms into a shape along the curved surface.
[0053]
When the glass plate 18 is further transported, the rollers 20E to 20I are lowered more than the previous rollers 20C to 20G, and the transport surface formed between the rollers 20E to 20I is the previous curved surface as a whole. It is deformed into a curved shape with a smaller radius of curvature (C). Here, as shown in the figure, the curved surface formed between the rollers 20E to 20I is not formed with a single curvature radius, but is composed of two curved surfaces having different curvature radii. Is formed. In other words, the curved surface having a small radius of curvature formed between the rollers 20E to 20F and the curved surface having a large radius of curvature formed between the rollers 20F to 20I are formed in combination. As a result, when the glass plate 18 passes over the rollers 20E to 20I, the glass plate 18 is further bent downward along the curved surface formed by the rollers 20E to 20I, and the shape along the curved surface, that is, two curvatures. It transforms into a curved surface with a radius.
[0054]
When the glass plate 18 is further transported, the rollers 20G to 20K are lowered more than the previous rollers 20E to 20I, and the transport surface formed between the rollers 20G to 20K is the previous curved surface as a whole. It is deformed into a curved shape with a smaller radius of curvature (D). Here, as shown in the figure, the curved surface formed between the rollers 20G to 20K is also formed by combining two curved surfaces having different radii of curvature as described above. That is, a curved surface having a small radius of curvature formed between the rollers 20G to 20H and a curved surface having a large radius of curvature formed between the rollers 20H to 20K are formed in combination. Thereby, when the glass plate 18 passes on the rollers 20G to 20K, the glass plate 18 is further bent downward along the curved surface formed by the rollers 20G to 20K, and the shape along the curved surface, that is, two curvatures. It transforms into a curved surface with a radius.
[0055]
Finally, when the glass plate 18 is positioned downstream of the conveying path of the forming zone 14, the rollers 20I to 20M are lowered more than the previous rollers 20G to 20K, and are formed between the rollers 20I to 20M. The conveying surface is deformed into a curved surface corresponding to the curvature of the glass plate 18 to be finally obtained (E). That is, the conveyance surface formed between the rollers 20I to 20J is curved into a curved surface having a radius of curvature R2, and the conveyance surface formed between the rollers 20J to 20M is curved into a curved surface having a radius of curvature R1. As a result, when the glass plate 18 passes over the rollers 20I to 20M, the glass plate 18 is further bent downward along the curved surface formed by the rollers 20I to 20M, that is, the shape to be finally obtained, that is, the radius of curvature. It is bent into a curved surface that is a composite of the curved surface of R1 and the curved surface of radius of curvature R2.
[0056]
Thus, according to the present embodiment, the glass plate 18 can be bent into a curved surface having a plurality of radii of curvature.
[0057]
In the present embodiment, the case where the glass plate 18 is bent and formed into a curved surface having two radii of curvature has been described, but by deforming a curved surface formed by a roller into a curved surface having a plurality of radii of curvature, The glass plate 18 having a desired composite shape can be bent.
[0058]
In the series of embodiments described above, straight rollers are used for the rollers 20A to 20M. However, the rollers 20A to 20M to be used are not limited to the straight rollers, and are orthogonal to the conveyance direction. A roller curved in the direction may be used. Thereby, the glass plate can be bent and formed into a shape (compound shape) curved in a plurality of directions.
[0059]
Moreover, it is preferable to change the curvature of the conveyance surface based on the shape data of the glass plate 18 to be obtained. In particular, since the shape of the glass plate for a vehicle window is prepared in advance as CAD data, the curvature can be easily changed by applying this CAD data to the motion controller.
[0060]
As with the roller conveyor 20 on the molding zone 14 side, the roller conveyor 22 on the air-cooling strengthening device 16 side also includes a rotation drive means and an up-down direction drive means, and these means can be separated by another or the same motion controller. It is preferable to control. In this case, the vertical position of each roller of the roller conveyor 22 may be changed so that the curvature of the conveying surface by the roller conveyor 22 is the same as the curvature of the glass plate 18.
[0061]
Moreover, it is preferable to divide | segment the upper blower head 24 and the lower blower head 26 of the air-cooling reinforcement | strengthening apparatus 16 according to the number of each roller of the roller conveyor 22. FIG. In this case, the divided upper blower head 24 and lower blower head 26 may be moved up and down so that the distance from the glass plate 18 becomes constant in conjunction with the vertical movement of the corresponding roller. Thereby, a glass plate 18 having a uniform strength on the entire surface can be obtained.
[0062]
On the other hand, in the case of rear glass for automobiles, a glass plate having a small radius of curvature near the left and right sides and a large radius of curvature at the center may be used. In this case, when the nip rollers 21 and 23 shown in FIG. 7 are arranged between the molding zone 14 and the air cooling strengthening device 16 and the nip rollers 21 and 23 nip the vicinity 19 of the left and right sides of the glass plate 18, 23 is rotated in the counterclockwise direction in FIG. Accordingly, the left and right sides of the glass plate 18 can be forcibly bent into a desired shape (a shape having a small radius of curvature) by the nip rollers 21 and 23, so that the molding apparatus 10 can be used as a rear glass molding apparatus. it can.
[0063]
Further, in the above embodiment, each roller is moved downward and upward to form a convex wavefront downward, and this wavefront is advanced. Conversely, each roller is moved upward and downward. Thus, it is also possible to form a wavefront having a convex shape on the top and to advance the wavefront. In this case, the edge of the glass plate hangs down due to its own weight, not the center of the glass plate. In view of the smooth conveyance of the glass plate, it is preferable to move each roller down and up to advance a convex wavefront.
[0064]
In the above embodiment, the rollers 20A, 20B,... Are moved up and down by the action of the rack and the pinion, but various methods other than this method are used for the vertical drive means. For example, as the vertical driving means, a system as shown in FIG. 8 or FIG. 9 may be used.
[0065]
The vertical driving means shown in FIG. 8 is of the type using a feed screw and is configured as follows.
[0066]
Each roller 70, 70,... Is rotatably supported by a moving frame 72, 72,... Having both ends formed in a concave shape via bearings 74, 74,. In addition, the spindles of servo motors 80, 80,... Are connected to one end of each of the rollers 70, 70,. Each of the rollers 70, 70,... Is rotated at a predetermined angular velocity by driving the servo motors 80, 80,.
[0067]
The moving frames 72, 72,... That support the rollers 70, 70,... Are supported by the fixed frame 82 so as to be movable up and down via LM (linear motion) guides. In the LM guide, guide rails 84, 84,... Are arranged in the vertical direction on the moving frames 72, 72,..., And guide blocks disposed on the fixed frame 82 side on the guide rails 84, 84,. 86, 86,... Are engaged.
[0068]
Further, nut members 88, 88,... Are fixed to the lower center portions of the respective moving frames 72, 72,..., And screw rods 90, 90,. It is screwed. The screw rods 90, 90,... Are rotatably supported by bearings 92, 92,... Disposed on the fixed frame 82, and driven pulleys 94, 94,. . On the other hand, servo motors 96, 96,... Are arranged on the fixed frame 82, and drive pulleys 98, 98,. The drive pulleys 98, 98, ... and the driven pulleys 94, 94, ... are wound around the drive belts 100, 100, ..., and the servo motors 96, 96, ... are passed through the drive belts 100, 100, .... Is transmitted to the screw rods 90, 90,. When the screw rods 90, 90,... Rotate, the moving frames 72, 72,..., That is, the rollers 70, 70,.
[0069]
The vertical driving means using the feed screw is configured as described above. In FIG. 8, reference numeral 102 indicates a heater provided in the molding zone 14.
[0070]
On the other hand, the up-down direction driving means shown in FIG. 9 is a system using a pantograph and is configured as follows.
[0071]
Each roller 70, 70,... Is rotatably supported by a moving frame 72, 72,... Having both ends formed in a concave shape via bearings 74, 74,. In addition, the spindles of servo motors 80, 80,... Are connected to one end of each of the rollers 70, 70,. Each of the rollers 70, 70,... Is rotated at a predetermined angular velocity by driving the servo motors 80, 80,.
[0072]
The lower ends of the moving frames 72, 72,... Are pin-coupled to the tips of the links 106, 108 via brackets 104, 104,. The links 106 and 108 are arranged so as to intersect with each other, and are pin-coupled to each other at the intersection. Further, the base ends of the links 106, 106,... On one side are pin-coupled to brackets 112, 112,... Disposed on the fixed frame 110, and the base ends of the links 108, 108,. The part is pin-coupled to the rod tip of cylinders 114, 114,. When the cylinders 114, 114,... Are driven to expand and contract the rods, the moving frames 72, 72,... Are moved up and down by the action of the links 106, 108, and as a result, the rollers 70, 70,. The
[0073]
The vertical driving means using the pantograph is configured as described above. In FIG. 9, reference numeral 102 indicates a heater provided in the molding zone 14.
[0074]
In the embodiment shown in FIG. 1, the molding zone 14 is provided in the enclosure of the heating furnace 12. That is, the molding zone 14 is provided in the heating furnace 12 and on the downstream side of the heating furnace 12. In the glass plate bending apparatus according to the present invention, in addition to (i) providing the forming zone in the heating furnace, (ii) providing the forming zone outside the heating furnace, (iii) part of the forming zone outside the heating furnace. It can also be provided. The position where such a molding zone is provided can be appropriately selected from the above (i) to (iii) according to the size and the bent shape of the glass plate.
[0075]
First, the relationship between the thickness of the glass plate and the position of the forming zone will be described. The strengthening treatment after the glass plate is bent is affected by the thickness of the glass plate. That is, the strengthened glass plate has a compressive stress on the surface and a tensile stress on the inside. These residual stresses are caused by a temperature difference between the glass plate surface and the inside of the glass plate, which is caused by rapid cooling of the heated glass plate. If the thickness of the glass plate is small, it is difficult to obtain this temperature difference. Therefore, in the strengthening treatment of the glass plate having a small thickness, it is necessary to increase the cooling ability during rapid cooling. One means for increasing the cooling capacity is to increase the blowing pressure and the air volume of the cooling air. In addition, there is a means for increasing the temperature of the glass plate during rapid cooling.
[0076]
In the case of (i), since the glass plate can be bent in a heating furnace, the glass plate after bending can be immediately conveyed to the air-cooling strengthening device. Therefore, a glass plate can be conveyed to an air cooling strengthening device, without the temperature of a glass plate falling. Therefore, the arrangement of the forming zone (i) is superior to the bending / strengthening treatment of the glass plate having a small thickness.
[0077]
Next, the relationship between the bent shape of the glass plate and the position of the forming zone will be described. When the glass plate is bent into a curved shape, the forming zone is provided with means for bending the glass plate in a direction orthogonal to the conveying direction. If this means is provided in the heating furnace, it is difficult to ensure a closed space in the heating furnace. Therefore, the malfunction that the temperature in a heating furnace cannot be kept at predetermined temperature arises. Therefore, by providing this means outside the heating furnace, the temperature inside the heating furnace can be stabilized. Therefore, the arrangement of the forming zone (ii) is advantageous when the glass plate is bent and formed into a compound curve.
[0078]
Furthermore, (iii) is superior as a compromise between (i) and (ii) in the bending / strengthening process in which a thin glass plate is bent into a multi-curved shape. And the arrangement | positioning of the bending molding zone of (iii) is preferable not only in the positioning of a mere compromise plan but in the next point. That is, according to the demand of a small variety of products in the automobile industry, it is required to bend and mold many types of glass plates with a single glass plate bending apparatus. Depending on the model, the thickness of the glass plate varies, and the bent shape of the glass plate also varies. Therefore, it is advantageous that glass plates having various thicknesses having various thicknesses can be formed with a glass plate bending apparatus having the same specifications. And the arrangement of the molding zone which can be adapted to the situation of such a small quantity and a wide variety is the arrangement of (iii).
[0079]
【The invention's effect】
As described above, according to the method and apparatus for bending a glass plate according to the present invention, a plurality of rollers are moved up and down in accordance with the conveyance position of the glass plate, thereby curving the conveyance surface formed by the rollers. Since the glass plate is bent to have a predetermined curvature by its own weight, the glass plate can be bent without using a plurality of rollers having a curvature corresponding to the model. Therefore, according to the present invention, it is possible to omit the roller replacement work that has been conventionally required.
[0080]
Further, according to the present invention, another type of glass plate can be formed simply by changing the vertical movement control data of the roller, so that the job change time can be substantially eliminated. In addition, since the plurality of rollers simply move up and down and the portion of the conveying surface where the glass plate is located becomes a curved surface, and only the curved surface advances, the glass plate is smoothly conveyed.
[0081]
Moreover, a glass plate without a damage | wound can be obtained by controlling the rotational drive means of a some roller so that the conveyance speed of the horizontal direction component of a glass plate may become equal.
[0082]
Furthermore, by bending the conveyance surface formed by the rollers into a curved surface having a plurality of curvature radii, it is possible to bend and form not only a glass plate having a single curvature radius but also a glass plate having a plurality of curvature radii. it can.
[Brief description of the drawings]
FIG. 1 is a perspective view showing the structure of a glass sheet bending apparatus according to an embodiment of the present invention.
FIG. 2 is a transition diagram showing a bending operation of a glass plate by a plurality of rollers arranged in a forming zone.
3 is a perspective view of the transition diagram shown in FIG.
FIG. 4 is an explanatory diagram showing the structure of roller rotation driving means and vertical movement means.
FIG. 5 is an explanatory diagram showing the conveyance speed of the horizontal component of the glass plate.
FIG. 6 is a transition diagram showing a bending operation of a glass plate by a plurality of rollers arranged in a forming zone.
FIG. 7 is an explanatory diagram in which a nip roller for forced bending is disposed between a forming zone and an air cooling strengthening device.
FIG. 8 is a perspective view showing the structure of another embodiment of a vertically moving means.
FIG. 9 is a perspective view showing the structure of another embodiment of a vertically moving means.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Glass plate bending apparatus, 12 ... Heating furnace, 14 ... Molding zone, 16 ... Air-cooling strengthening apparatus, 18 ... Glass plate, 20 ... Roller conveyor, 20A-20M ... Roller, 38, 56 ... Servo motor

Claims (5)

The glass plate is heated to a bending temperature in a heating furnace, and the glass plate is brought to a predetermined curvature by its own weight while the heated glass plate is conveyed along a conveying surface formed by a plurality of rollers of a roller conveyor. In the bending method of the glass plate to be bent,
A plurality of rollers at a position where the glass plate is conveyed are moved up and down as the glass plate is conveyed, and a desired curve that is curved in the conveyance direction of the glass plate by at least a part of the conveyance surface by the plurality of rollers at the position. As the glass plate is conveyed, the rollers are sequentially moved up and down to advance the curved surface in the glass plate conveyance direction along with the glass plate conveyance, and the glass plate is conveyed while conveying the glass plate. A method for bending a glass plate, wherein the glass plate is bent along a curved surface. 2. The method of bending a glass plate according to claim 1 , wherein the curvature radius of the curved surface is reduced toward the downstream side in the conveying direction of the glass plate. 3. The glass plate bending method according to claim 1, wherein the curved surface is formed into a curved surface having a plurality of curvature radii, and the glass plate is bent into a curved surface having a plurality of curvature radii. In a glass plate bending apparatus comprising a heating furnace for heating a glass plate to a bending temperature, and a forming means for bending a glass plate provided downstream of the heating furnace to a predetermined curvature,
The molding means includes
A roller conveyor comprising a plurality of rollers forming a conveying surface for conveying the glass plate;
Vertical driving means for moving the plurality of rollers up and down;
A plurality of rollers at a position where the glass plate is conveyed forms a desired curved surface curved in the conveyance direction of the glass plate on at least a part of the conveyance surface. Control means for controlling the driving means so that the curved surface advances in the conveying direction of the glass plate by moving a roller up and down;
A glass plate bending apparatus characterized by comprising: 5. The glass according to claim 4 , further comprising a rotation driving unit configured to rotate the roller, wherein the control device controls the rotation driving unit so that conveyance speeds of horizontal components of the glass plate are equal. Plate bending equipment.

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