MXPA99001222A - Method and apparatus for bending sheet glass - Google Patents

Abstract

An apparatus for bending sheet glass wherein the distances between at least part of transfer rollers are adjusted to become unequal, whereby high-quality sheet glass free from optical strain are molded, the distances between transfer rollers (12A-12G) arranged from an outlet (17) of a heating furnace (16) being adjusted to become unequal and to increase gradually in a downstream direction.

Description

FLEXION METHOD AND FLEXION APPARATUS FOR GLASS SHEETS BACKGROUND OF THE INVENTION TECHNICAL FIELD The present invention relates to a bending method and a bending apparatus for glass sheets. In particular, the present invention relates to a bending method and a bending apparatus for glass sheets in which the glass sheets heated to a bending temperature are transported by a heating furnace and the glass sheets are bent in a shape along a transport path under its own weight.

TECHNICAL BACKGROUND As an apparatus for bending glass sheets during transport by means of rollers, roller-based conveyors have been known (for example, US-A-4,311,509). Said roller-based conveyors include a plurality of conveyor rollers that are bent to have arbitrary bends. The conveyor rollers are provided at equal distances. The conveyor rollers provide a transport path that has arbitrary curvatures in the apparatuses. Glass sheets that have been heated to a softening temperature in a heating furnace are transported on the transport path from an oven exit of > heating to a certain direction. The glass sheets that are transported on the transport path are folded in one way along the transport path under their own weight during transport. However, conventional conveyor rollers cause scratch defects on a surface of the glass sheets after the formation. The defects of »Streaks are optical distortions caused during bending of glass sheets, and distortion degrades the quality of glass sheets. The causes of optical distortion will be explained Referring to Figure 7. Figure 7 is a transient view showing how a glass sheet 1 that has been provided from an outlet of a heating furnace is transported by a plurality of conveyor rollers 2A, 2B, 2C, 2D that they form a transport route. The glass sheet 1 is bent in a certain way, being transported by the conveyor rollers 2A, 2B, 2C, 2D. As shown in Fig. 7 (B), when the glass sheet 1 has a front portion A placed in contact with the conveyor roller 2A, the heat of the front portion IA towards the conveyor roller 2A. Said removal of heat causes one side of the glass sheet 1 on the conveyor roller to be thermally shrunk, causing the front portion IA to warp downward (C). As shown in (D), the warped front portion IA runs on the conveyor roller 2B as it passes over the conveyor roller 2B. This creates a state such that the entire glass sheet 1 is raised slightly. As shown in (E), when the front portion 1 (A) has passed the conveyor roller 2B, the complete glass sheet 1 returns to a position before being lifted, and makes contact with the conveyor rollers 2A, 2B. (F) and (G) are views that > show a repetition of the operations in (D) and (E). As explained, the glass sheet 1 is transported on the conveyor rollers ÍA, 2B, 2C, 2D, being vibrated slightly in a vertical direction due to the presence of Said buckling movement of the front portion IA. In (C) - (G), the attention is directed to arbitrary points a and b on the glass sheet 1 (actually, > lines perpendicular to a transport direction). Point a rises (D) after doing. contact with the roller conveyor 2A, and makes contact with the conveyor roller 2B after the glass sheet 1 lowers (E). Then, the point a rises (F) and makes contact with the conveyor roller 2C when it has lowered (G). In other words, the glass sheet 1 makes contact sequentially with the rollers conveyors 2A, 2B, 2C, 2D, during transport. On the other hand, the point b is located on the conveyor roller 2A as shown in (D) when the glass sheet 1 is lifted. After that, the point b is located between the conveyor roller 2A and the conveyor roller 2B at (E), where the glass sheet 1 has lowered. This movement avoids contact with the conveyor roller 2A. The repetitions of said movement avoid contact with the conveyor rollers 2B, 2C, 2D as well. In other words, the point b does not make contact with the conveyor roller ÍA, 2B, 2C, 2D at all during the transport of the glass sheet 1. »When conventional conveyor rollers are used, portions (eg, point a) that are cooled by contact with conveyor rollers and portions (eg, point b) ) that are not cooled by conveyor rollers do not coexist at all on formed glass sheets. This creates differences between these portions in terms of thermal shrinkage, and the differences are exhibited as streak defects in the formed glass sheets. These are the causes of the optical distortion. The present invention has been conceived considering these problems, and an object of the present invention is to provide a bending method and a bending apparatus for glass sheets capable of forming sheets of glass having an adequate quality and free of any distortion. optics.

DESCRIPTION OF THE INVENTION To achieve this object, the present invention provides a method for bending glass sheets in which the glass sheets are transported in a heating oven to be heated to a certain bending temperature, the heated glass sheets are transported on a path of transport including a plurality of conveyor rollers provided from an outlet of the heating furnace to a downstream direction, and certain curvatures are given thereto by the rollers, and the glass sheets are folded into a shape along the path of transport under its own weight; wherein in addition the conveyor rollers are provided to establish at least some distances between adjacent conveyor rollers in such a way that they are different from the other distances, and also because the glass sheets are transported on the transport path. The present invention also provides an apparatus for bending glass sheets comprising a heating furnace for heating glass sheets to a bending temperature, a conveyor for conveying the glass sheets in the heating furnace and a transport path including a plurality of conveyor rollers provided from an outlet of the heating furnace to a downstream direction, and are given certain curvatures by the rollers, wherein the heated glass sheets are transported on the conveying path to be bent into a desired shape; where in addition the conveyor rollers are provided ) to establish at least some distances between adjacent rollers 5 conveyors in such a way that they are different from the other distances. As explained, the present invention is based on the discovery that the true cause of the optical distortion mentioned above is equality in the distances between the conveyor rollers, and the present invention establishes some of the distances between the conveyor roller such that they are unequal to improve optical distortion. When the distances between the conveyor rollers are equal, the portions that are cooled by contact with the conveyor rollers and the portions that are not cooled by the conveyor rollers at all, coexist in formed sheets of glass. East The phenomenon causes optical distortion in the glass sheets.

On the other hand, when at least some of the distances between the conveyor rollers are set to be unequal according to the present invention, the glass sheets can make contact with the conveyor rollers in any portions thereof. This avoids the occurrence of scratches on the glass sheets, improving the quality of them.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view showing I the bending apparatus for glass sheets according to a embodiment of the present invention, and the method of bending for glass sheets according to a mode using the flexure apparatus; Figure 2 is a front view showing an example of the arrangement of a conveyor roller of Figure 1; »Figure 3 is a partially elongated sectional view showing an example of a conveyor roller of Figure 2; Figure 4 is an enlarged partially sectional view showing another example of a conveyor roller of Figure 2; Figure 5 is a schematic view to explain? the distances between the conveyor rollers of Figure i; Figure 6 is a transient view in which a glass sheet is transported by the conveyor rollers of Figure 1; and Figure 7 is a transient view in which a glass sheet is conveyed by conventional conveyor rollers.

BEST WAY TO CARRY OUT THE INVENTION The apparatus of the invention will now be described in detail I bending for glass sheets according to a modality preferred of the present invention, with reference to the accompanying drawings. In Figure 1 there is shown a perspective view of the bending apparatus for glass sheets according to the preferred embodiment of the present invention, and an embodiment of the bending method for glass sheets using the apparatus of flexion. > As shown in this figure, the flexing apparatus for glass sheets 10 includes a plurality of conveyor rollers 12, 12"". The conveyor rollers 12, 12"" are provided in parallel with one another to provide a transport path 14. The transport path 14 formed by the conveyor rollers 12, 12"" is provided at an outlet of a heating furnace 16. In the heating furnace, the glass sheets are transported by a suitable conveyor. As this conveyor there are several types of measures. Since the conveyor rollers are provided from the outlet of the heating furnace to a downstream direction, it is preferred that the conveyor in the heating furnace comprises a plurality of rollers. Conveyor rollers 12 on one side upstream of the transport path 14 are configured in a linear fashion, and the conveyor rollers on a downstream side of the transport path 14 are bent such that they have certain curvatures. The curvatures of the conveyor rollers 12 are determined in such a way that the curvatures increase (decrease the radii of curvature) gradually from the upstream side to the downstream side of the transport path 14, and so that a certain curvature is established on the side downstream of the transport path 14. A glass sheet 18 is heated to a bending temperature (typically 650 ° C-700 ° C) in the heating furnace and is provided on the transport path 14. The glass sheet 18 heated is bent in one way along the transport path 14 under its own weight while being transported on the transport path 14. Certain curvatures of the conveyor rollers are determined in such a way as to correspond to a desired shape for the glass sheets . In particular, the glass sheets can be slightly deformed when cooled after bending. Certain curvatures of the conveyor rollers include curvatures which are determined taking into account said deformation. As shown in figure 2, each conveyor roller 12 comprises a guide shaft 20 and a plurality of rings 22, 22"" carried on the guide shaft 20, and is mounted to a support frame 38. A housing for left gear 30 is provided at a lateral end of the rings 22, and a right gear housing 32 is provided at a right side end of the rings. The support frame 38 has both ends provided with mounting members 38a, and both ends of the guide arrow 20 are fixed to the mounting members 38a, 38a. On one left end of the left gear housing 30 are provided first and second gear wheels 30A, 30B. The second sprocket 30B is coupled to a gear wheel 44 of a drive motor 42 through a? chain 40 to receive a rotating force. The driving motor 42 is fixed to the support frame 38 by means of screws 46, 46"". A sleeve 48 is adapted between the left gear housing 30 and the guide arrow 20. The guide arrow 20 has a retainer ring 50 adapted in a portion thereof on a left end side of the left sprocket housing 30, and the retainer ring 50 is fixed to the guide shaft 20 by means of a pin 52. that the gear housing left, the right sprocket housing 32 is fixed to a right end portion of the guide shaft 20. The right sprocket housing 32 is provided with first and second sprockets 32A, 32B as well as the sprocket housing left 30. The explanation of The first and second sprockets 32A, 32B will be omitted, since these sprockets are equal to the first and second sprockets 30A, 30B of the left sprocket housing 30. The guide shaft 20 also has a retainer ring 50. adapted in a portion thereof on a right end side of the right sprocket housing 32, and the retainer ring 50 is fixed to the guide shaft 20 by means of a bolt 52. By such arrangement, both ends of the guide shaft 20 are fixed by the detent rings 50, and the rings 22, 22 are kept with the upper ends thereof in contact with each other between the left gear housing 30 and the right gear housing 32. It is not It is necessary to provide the driving motor 42 on each conveyor roller. When the gears (30A, 32A) of adjacent conveyor rollers are coupled, the rotary movement of a conveyor roller with the driven motor 42 can be transmitted to its adjacent conveyor roller. The rotary movement by the driving motor can be transmitted to a conveyor roller near the adjacent conveyor roller. The structure of the conveyor rollers will be described in detail, with reference to Figure 3. In each of the conveyor rollers 12, the rings 22, 22"" are rotatably supported on the guide shaft 20. The rings 22 comprise a body of ring 22A and a collar 22B. The ring body 22A has a cylindrical shape and has a central portion formed with a large-diameter opening of through-hole 22a in one end surface thereof, and a small-diameter opening of through-hole 22b in the other end surface. The small diameter of the through hole 22b has a hole diameter larger than the outer diameter of the guide shaft 20. The large diameter of the through hole 22a has a sleeve 24 inserted therein, and the sleeve 24 is inserted over the arrow guide 20. By such arrangement, the rings 22 are carried on the guide arrow 20 to be rotatable. Each ring body 22A has both end surfaces formed with annular ribs 22c, 22c, and threaded holes 22d, 22d are formed in two locations of an outer peripheral surface of each of the ribs. Each collar 22B is placed on an outer periphery of each ring body 22A by shrinkage adaptation for example. Each collar 22B has substantially the same width as the full width of each ring body 22A, and each collar has holes 22e formed therein in alignment with the threaded holes 22d in a related ring body 22A. The adjacent rings 22, 22 are coupled together by a flexible cylindrical member 26 which is provided on the annular ribs 22c, 22c, of the adjacent rings and which is made of rubber. Each flexible cylindrical member 26 has both ends formed with threaded through holes 26a. Screws 28 (replaceable by clamping members such as machine screws and fasteners) are inserted into the threaded through holes 26a to be coupled with the threaded holes 22b and in the related ribs 22c, engaging the rings 22, 22 adjacent to each other. Each flexible cylindrical member 26 has an outwardly projecting portion 26b formed therein across the entire circumference at a central portion in a width direction thereof. Each sprocket housing 30 and its adjacent ring 22 are coupled through a flexible cylindrical member 26. By such an arrangement, the torque transmitted to each sprocket 30B can be transmitted to adjacent rings 22, 22 one by one through of the flexible cylindrical members 26, providing to each conveyor roller 20 a rotary force necessary to transport glass sheets. In Figure 4 another example of the structure of the conveyor rollers is shown. In this example, the adjacent rings 22 are coupled by a rigid cylindrical member 58 which is interposed therebetween and is in the form of a bellows. The rigid cylindrical member 58 in the form of a bellows is made of a material having high strength such as steel, and has an expansion and contraction portion 58a formed in an intermediate portion thereof in a width direction thereof. Both ends of the rigid cylindrical member 58 are mounted to the annular ribs 22c, 22c of the adjacent rings 22, 22 and both ends of the rigid cylindrical member 58 are fixed to the annular ribs 22c, 22c by screws 28. The coupling of the wheel housing toothed left 30 with its adjacent ring 22 and the coupling of the right sprocket housing 32 with its adjacent ring 22 are made by means of similar rigid cylindrical members 58, and the coupling is set by screws 28, 36 as in the first example of the conveyor rollers. In the second example, variations in the distance between the adjacent rings 22, 22 caused by the vibration of the adjacent rings 22, 22 can be absorbed by the expansion and contraction portion 58a in a bellows shape of the rigid cylindrical member 58. When one of the rings 22 of a conveyor roller is replaced by a new one in this example, a screwdriver is inserted from the holes 22e in the relevant collar 22b, the screws 28 of the ring 22 to be replaced are loosened by the screwdriver to remove the limbs relevant flexible cylindrical members 26b of ring annular ribs 22c; the ring is replaced by the new ring 22, and the cylindrical flexible members 26b are tightened to the new ring 22 by the screws 28. Since each guidewire is bent, the adjacent rings need that the vibration of each ring is easy and that the adjacent rings are coupled in such a way as to ensure the transmission of the torque. The cylindrical members are suitable for coupling the rings any time said members are difficult to deform with respect to a > force in a twisting direction and relatively easy to be deformed with respect to a direction of flexion. From this point of view, it is preferred that the adjacent rings be coupled by the flexible cylindrical member 26 shown in Figure 3 or by the rigid cylindrical member 58 shown in Figure 4. The flexible cylindrical member 26 needs to have a > thick wall to ensure the transmission of torque between the rings. However, there is a possibility that said thick wall degrades the oscillatory property of the rings. The formation of the annular portion that is projected outwardly in a central portion of the cylindrical member in the width direction can easily bend the cylindrical member, even if the cylindrical member has a thick wall. Since the annular portion projecting outward has deformation loads applied repeatedly to it As compared with the other portions of the cylindrical member, it is preferred that the wall of the annular portion projecting outwards be thicker than that of the other portions. Although the transmission of the torque between the rings is ensured by the rigid cylindrical member 58 as In a rigid member, there is a possibility that the oscillatory property of the rings may be degraded if certain measures are not taken. The cylindrical member can be easily bent by providing the cylindrical member with a bellows shape. The number of push-ups of the form of > bellows to meet the needs mentioned above, taking into account the material, the wall thickness and so on, of the cylindrical member. As shown in Figure 1, the conveyor rollers 12, 12 according to this embodiment are provided in such a way that the distances between the rollers adjacent conveyors are unequal. The distances > they mean horizontal distances between central rotating arrows of adjacent conveyor rollers as shown in Figure 5. The unequal distances shown in Figure 1 will be explained in detail, with reference to the Figure 5. Seven conveyor rollers 12A-12G which are provided from the outlet 17 of the heating furnace 16 are established in that order so that the distances (P1-P6) between "the respective conveyor rollers are different, the distances are established in such a way that they expand gradually to the downstream side (P1 <P2 <P3 <P4 <P5 <P6). In the example shown, Pl is equal to 60 mm, and P2, P3, P4, P5 and P6 gradually increase by 4 mm, respectively. The distances (P1-P3) of the conveyor rollers 12A-12D that are located in the The surroundings of the outlet 17 of the heating furnace 16 are set to minimize the buckling amount of the front portion 19 of the glass sheet 18. The distances between the eighth and its subsequent conveyor rollers 12, 12 - are set to repeat the distances from P1-P6 or to be unequal to each other. Inequality can include a case in which all distances are unequal and a case in which some of the distances are unequal. A small number of unequal distances can result in an insufficient contribution to a decrease in optical distortion. To deal with this problem, it is preferable that a certain number of distances be unequal to each other. In particular, it is preferable that the distances change gradually as shown in the example, since the provision of the conveyor rollers can be carried out effectively and the gradual changes can contribute significantly to a decrease in the optical distortion. The operation of the conveyor rollers 12 according to this embodiment will now be described with reference to Fig. 6. In Fig. 6 there is shown a transient view showing how the glass sheet 18 which has been provided from the outlet 17 of the Heating furnace 16 is conveyed by the various conveyor rollers 12A-12E. The glass sheet 18 is bent in a certain way, being transported on the conveyor rollers 12A-12E. As shown in Figure 6 (A), when the glass sheet 18 has the front portion 19 brought into contact with the conveyor roller 12A, the front portion 19 is cooled as the heat is removed by the conveyor roller 12A. As a result, the glass sheet 18 is bent downward by heat shrinkage (B). As shown in (C), the > The front bent portion 19 runs on the conveyor roller 12B when the conveyor roller 12B passes. This creates a state in which the entire glass sheet 18 is raised slightly. As shown in (D), when the front portion 19 has passed the conveyor roller 12B, the complete glass sheet 18 returns to the position before having been lifted, and the glass sheet 18 makes contact with the > conveyor rollers 12A, 12B. (E) and (F) are views that show a repetition of the operations in (C) and (D). As explained, the glass sheet 18 is transported on the conveyor rollers 12A-12E, being vibrated slightly in a vertical direction due to the presence of said buckling movement of the forward position 19. Attention is directed to arbitrary points a, b, c, d »And e on the glass sheet 18 (actually, lines perpendicular to the transport direction) in (B) - (F). He point a rises (C) after having made contact with the conveyor roller 12A (B). When the glass sheet 18 has lowered (D), the point a goes beyond the transport roller 12B and is present between the transport roller 12B and the transport roller 12C. When the glass sheet 18 goes down after the point b has been present on the conveyor roller 12A (C), the point b makes contact with the conveyor roller 12B (D). The point c is present between the conveyor roller 12B and the conveyor roller 12C (E) after having made contact with the conveyor roller 12A (D). The point d which has not made contact with the conveyor roller 12A or with the conveyor roller 12B makes contact with the conveyor roller 12C when the glass sheet occupies a position shown in (E). On the other hand, the point e that has not made contact with any of the conveyor rollers 12A-12C makes contact with the conveyor roller 12D when the glass sheet occupies a position shown in (F). As explained, the mode according to the present invention allows any position on the glass sheet 18 to contact at least one conveyor roller 12 since the distances between the conveyor rollers 12A-12E-are set to be unequal. As a result, the optical distortion that occurs in the glass sheet 18 can be dispersed to prevent scratch defects from occurring in the glass sheet 18, providing the glass sheet 18 with a suitable quality. According to this mode, the glass sheet 18 can be transported smoothly, since the amount of buckling of the front portion 19 is minimized by adopting said arrangement wherein the distances (P1-P3) between the conveyor rollers 12A -12D in the vicinity of the outlet 17 of the heating furnace 16 are narrow. The distances between the conveyor rollers in the vicinity of the heating furnace outlet can be extended in an inverse manner. When a sheet of glass that has been provided from the outlet of the heating furnace makes contact with the conveyor rollers on the upstream side, the conveyor rollers remove the heat from the glass sheet to cool it causing it to warp. If the distances between the conveyor rollers in the vicinity of the output of the heating furnace are large, the amount of buckling of the front portion increases and the front portion enters a gap between the conveyor rollers, causing transport problems in some cases. The amount of buckling of the front portion can be minimized by adopting an arrangement such that the distances between the conveyor rollers in the vicinity of those of the outlet of the heating furnace are narrow. By such arrangement, a glass sheet can be smoothly transported to reduce optical distortion due to transport problems. From this point of view, it is preferred that the distances between the conveying rollers provided in the vicinity of the heating furnace outlet are set to become narrower than the distances between the subsequent conveyor rollers. The distances (P1-P6) of the conveyor rollers 12 can be set appropriately, depending on the transport speed of the glass sheet 18 or the diameter of the conveyor rollers 12. The specific methods to consider the transport speed and the diameter they are explained later. The glass sheets that have been heated in the heating oven 16 and are normally hardened after they have been bent over the transport path 14. If the temperature of the glass sheets decreases too much, the tempering treatment can not be out in sufficient form. It is necessary to favor a drop in temperature as small as possible in the glass sheets on the transport path 14. In principle, it is possible to prevent the glass sheets from being cooled to a temperature lower than the temperature necessary for the tempering treatment increasing the speed of transportation of the glass sheets. On the other hand, if the transport speed of the glass sheets increases too much, they vibrate during the transportation causing problems the same. From this point of view, it is preferable that the transport speed of the glass sheets be on a scale of 4.00 mm / sec to 600 mm / sec. Under the circumferences, it is preferred that the full length of the tansporte travel in the direction of transportation is on a scale of 1,300 mm to 2,000 mm, considering a drop in the temperature of the glass sheets during transportation and a temperature capable of bending the glass sheets. It is preferable that the transport path 14 has a width in a direction perpendicular to the transport direction on a scale of 800 mm to 1,200 mm. A width on such a scale can handle a variety of dimensions of glass sheets when glass sheets are folded to eg car side lights (usually the glass sheets are folded in a direction of width perpendicular to the direction transport). The glass sheets for most of the »Car side lights have a width in a direction perpendicular to the direction of transport that ranges from about 300 mm to about 600 mm. The fact that the width of the transport path 14 in the direction perpendicular to the direction of transport is in the range of 800 mm to 12,000 mm means that the conveyor rollers 12 have per se a length of about 800 mm to w about 12,000 mm (the conveyor rollers are not considered to be bent). To provide a certain amount of stiffness to the conveyor rollers having a length of about 800 to about 12,000 mm, it is preferred that the conveyor rollers 12 have a diameter on a scale of 40 mm to 100 mm. If the distances between the conveyor rollers are very large, the glass sheets are combated in separations between the conveyor rollers during transportation.

From this point of view, the upper limit of the distances is on a scale of 80 mm to 120 mm. When the distances gradually increase towards the downstream direction as mentioned above, the distances return to the distances in the vicinity of the output of the heating furnace at a place with the maximum distance, and the subsequent distances are gradually increased towards the direction downstream again (such an arrangement is repeated when necessary). Before the glass sheets are fully adapted to bent profiles of the conveyor rollers 12, the glass sheets have lateral edges extending in the transport direction supported by the conveyor rollers 12 (there is a space between a central region of the conveyor rollers 12). glass sheets and conveyor rollers). In this way, the glass sheets have the central region warped downwards, providing a folded shape to the glass sheets. To smoothly transport the glass sheets, it is required that they have the supported portions of them located at a nearly constant level in a vertical direction. When the glass sheets have the supported portion held at said constant level, the bent conveyor rollers have end portions thereof placed on and a central portion thereof placed below the glass sheets. Since the respective conveyor rollers have different curvatures, the respective conveyor rollers have the end portions placed at a different level. Since the curvatures of the conveyor rollers gradually increase toward the transport direction, the levels of the end portions of the conveyor rollers gradually rise toward the transport direction. From this point of view, it is preferred that the toothed wheels of the respective conveyor rollers are coupled by chains as measures to provide rotational movement to the respective conveyor rollers. Although the levels of the end portions of the conveyor rollers gradually increase toward the transport direction, the differences between the levels can be absorbed by the chain to smoothly transmit the rotary motion. To modify the respective distances between the conveyor rollers in one case with the chain used as mentioned above, it is simple to remove elements from the chain. Said method can decrease the distances by a length corresponding to chain elements between adjacent conveyor rollers (1/4 of the length of a chain element). Since the chain is required to have a certain degree of stiffness to provide rotational movement to the conveyor rollers, it is also required that the chain elements have a preferable size. From this point of view, it is preferred that the distances be modified by a shorter length on a scale of 2 mm to 10 mm. Consideration is directed to the full length of the transport path of 1, 300 mm to 2,000 mm, as well as the preferable diameter scale of the conveyor rollers and the preferable upper limit of the distances between the conveyor rollers. According to this consideration, it is preferred that the conveyor rollers are provided at different distances, although distances that have the same length in 2 to 10 places, in particular 2 to 5 places in the transport path, are present. When the distances are provided such that arrangements with gradually increased distances are repeated from the exit of the heating oven, it is preferred that the repeated arrangements be provided in 2 to 10 places, in particular 2 to 5 places.

INDUSTRIAL APPLICABILITY As explained, according to the bending method and the bending apparatus for glass sheets of the present invention, at least some of the distances between the different conveyor rollers can be set to be unequal, forming glass sheets that They have an adequate quality and they are free of optical distortions.

Claims (12)

NOVELTY OF THE INVENTION CLAIMS

1. - A method for bending glass sheets, further characterized in that the glass sheets are transported in a heating furnace to be heated to a certain bending temperature, the heated glass sheets are transported on a transport path that includes a plurality of rollers conveyors provided from an outlet of the heating furnace to a downstream direction, and are given certain curvatures by means of the rollers, and the glass sheets are bent into a shape along the conveying path under their own weight; further characterized in that the conveyor rollers are provided to establish at least some of the distances between adjacent conveyor rollers such that they are different from the other distances, and in that the glass sheets are transported on the transport path.

2. A method for folding glass sheets according to claim 1, further characterized in that the conveyor rollers are provided to establish the at least some of the distances between the adjacent conveyor rollers in such a way that they are different from the distance between them. the other adjacent conveyor rollers, whereby the glass sheets are bent by contacting each point thereof with any of the conveyor rollers during the > transportation.

3. A method for folding glass sheets according to claim 1 or 2, further characterized in that the glass sheets are transported with the transport path having a length in a conveying direction established on a scale of 1400 mm to 2000 mm. 10 4.- A method for bending glass sheets of ^ according to one of claims 1-3, further characterized in that rollers having a diameter on a scale of 40 mm to 100 mm are used as the conveyor rollers. 5. A method for folding glass sheets according to one of claims 1-4, further characterized in that the glass sheets are transported with a shorter distance and the next shorter distance between the distances between the conveyor rollers has a 20 difference established on a scale of 2 mm to 10 mm. 6. A method for folding glass sheets according to one of claims 1-5, further characterized in that the glass sheets are transported with a distance between adjacent conveyor rollers close to 25 the outlet of the heating furnace established in such a way that it is narrower than that of the subsequent adjacent rollers. 7. An apparatus for bending glass sheets comprising a heating furnace for heating glass sheets to a bending temperature, a conveyor for transporting the glass sheets in the heating furnace and a transport path including a plurality of glass sheets. conveyor rollers provided from an outlet of the heating furnace to a downstream direction, and are given certain curvatures by means of the rollers, wherein the glass sheets are transported on the transport path to be bent into a desired shape; further characterized in that the conveyor rollers are provided to establish at least some of the distances between adjacent conveyor rollers such that they are different from the other distances. 8. - An apparatus according to claim 7, further characterized in that the transport path has a length in a transport direction that extends on a scale of 1400 mm to 2000 mm. 9. An apparatus for bending glass sheets according to claim 7 or 8, further characterized in that the rollers have a diameter on a scale of 40 mm to 100 mm. 10. An apparatus for folding glass sheets according to one of claims 7-9, further characterized in that a shorter distance and the next shortest distance between the distances between the conveyor rollers have a difference on a scale of 2 mm to 10 mm. 11. An apparatus for folding sheets of glass according to one of claims 7-10, further characterized in that a distance between adjacent conveyor rollers close to the heating oven outlet is set to be narrower than the distance between them. subsequent adjacent rollers. 12. An apparatus for bending glass sheets according to claim 11, further characterized in that the rollers are provided in such a way that the distances between adjacent conveyor rollers are gradually increased towards a downstream direction. 15 in a direction of transport, and the distances have a maximum value on a scale of 80 mm to 1200 mm, and because the rollers are provided in such a way that the distances fe ^ return to a value of the distance between the conveyor rollers near of the heating furnace outlet 20 in a place where the distances are gradually increased to become the maximum distance, and the distances are gradually increased again towards the downstream direction in the transport direction.