JP2014031318A - Glass plate manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the configuration of a cooling roller so as to properly devise both widthwise ends of a glass ribbon generated by flowing molten glass from a molding, and thereby securing a sufficiently wide product region of the glass ribbon.SOLUTION: A glass plate manufacturing method includes a step of holding both widthwise ends Ga thicker than a product region Gb of a glass ribbon G generated by flowing molten glass g from a molding 3 by a pair of cooling rollers 5 aligned so that roller shafts 5a extend on both ends from a center side in a width direction of the glass ribbon G from both top and rear sides, and avoiding shrinkage of the glass ribbon in the width direction. Protrusion parts 5b with which the widthwise ends Ga of the glass ribbon G are hooked in the width direction are formed on an outer periphery of the cooling rollers 5, so as to increase a contact area of the cooling rollers 5 and the glass ribbon G.

Description

  The present invention relates to a method for producing a glass plate, and more specifically, a glass plate comprising a cooling roller for sandwiching both end portions in the width direction of a glass ribbon produced by flowing molten glass from a molded body from both front and back sides. Regarding the method.

  In recent years, with the development of electronic devices and the like, flat panel displays (FPD) such as liquid crystal displays, plasma displays, field emission displays (including surface emission displays) and electroluminescence displays, sensor substrates, or solid-state imaging devices Various types of glass plates such as semiconductor package covers such as laser diodes and thin film compound solar cell substrates are used.

  This type of glass plate manufacturing method is referred to as an overflow down draw method or a slot down draw method in which molten glass is flowed down to produce a plate-like glass ribbon and solidified while being further flowed down. A technique and a technique called a float method in which molten glass is solidified while flowing out on a molten metal or a gas such as steam are widely used.

In particular, the overflow down-draw method supplies molten glass to the upper part of a molded body made of a heat-resistant member having a cylindrical shape or triangular prism shape (wedge shape), and the molten glass overflowing from the upper end of the molded body is disposed on both sides of the molded body. It has an initial stage of generating a plate-shaped glass ribbon by flowing along the surface and joining at the lower end of the molded body. In this case, the glass ribbon produced just below the formed body is still low in viscosity, and the glass ribbon shrinks in the width direction due to the surface tension.

  Therefore, in the initial stage of the glass plate molding, for the purpose of maintaining the glass ribbon at a predetermined width, a pair of both ends of the glass ribbon in the width direction immediately below the formed body are sandwiched from both the front and back sides (two pairs in total). ) Cooling rollers (Knurled Roll (wheel)) are provided, and both ends in the width direction of the glass ribbon are cooled by these cooling rollers (see Patent Documents 1, 2, and 3). In this way, the cooling of the glass ribbon and the accompanying solidification are promoted immediately below the molded body, and when the glass ribbon further flows down to near room temperature, it is cut into a predetermined length, and then desired. The glass plate will be produced.

  In this overflow down draw method, attempts have been made to cope with insufficient cooling of the glass ribbon or shrinkage in the width direction of the glass ribbon by improving the arrangement relationship of the cooling rollers. Specifically, according to Patent Document 4, it is disclosed that the cooling effect on the glass ribbon is enhanced by arranging cooling rollers in a plurality of stages and increasing the number of cooling rollers. Patent Document 5 discloses a configuration in which the roller shaft of the cooling roller is inclined so that friction generated between the cooling roller and the glass ribbon during the rotation of the cooling roller can apply a tensile force to the glass ribbon. ing.

  According to Patent Document 6, a pair of rolls having protrusions is disposed in the vicinity of both ends in the width direction of a molten glass ribbon supplied on a support (on a horizontal plane), and the width of the glass ribbon is increased. Discloses that a tensile stress in the width direction is applied to the glass ribbon by rotating the rolls about the axis.

Japanese Patent Publication No. 38-17820 JP 60-11235 A Special table 2007-528338 gazette JP 2007-51028 A JP-A-10-291826 JP 2002-47017 A

  In the above-described overflow downdraw method, generally, as shown in FIG. 12, both end portions in the width direction of the product region (region that will be a glass plate that will be a product in the future) Gb of the glass ribbon G (both in the width direction) (A region where the product is not a glass plate but discarded) Ga has a characteristic that the thickness ta is thicker. Such a situation is particularly noticeable in the current situation where the size of the glass plate for FPD is increased to meet the demand for improving the production efficiency of FPD, and the thickness is reduced to meet the demand for weight reduction of FPD. It has become.

  In addition, if the amount of molten glass that is supplied to the molded body and flows down from the demand for an increase in production per unit time under such a current situation, the amount of heat that is brought in per unit time is increased accordingly. Will also increase. Therefore, both ends in the width direction of the glass ribbon cannot be sufficiently cooled by the cooling roller, and the glass contracts. As shown in FIG. 13, the thickness ta of the both ends Ga in the width direction of the glass ribbon G is the product. It increases compared to the plate thickness tb of the region Gb. When such a situation occurs, not only the difference between the plate thickness ta of the glass ribbon G in the width direction both ends Ga and the plate thickness tb of the product region Gb increases, but also from the width direction both ends Ga to the product region Gb. The transition region Gc also increases, and it is substantially difficult to secure the product region Gb.

  As a technique for avoiding such a problem, it is possible to prevent the above-described shrinkage of the glass. Specifically, the cooling roller prevents the shrinkage of the glass ribbon G in the width direction, and the plate thickness ta of the width direction both ends Ga and It is conceivable to reduce the difference from the plate thickness tb of the product region Gb. However, the method of simply increasing the number of cooling rollers as disclosed in Patent Document 4 not only cannot properly prevent the shrinkage of the glass ribbon G in the width direction, but also complicates the apparatus unnecessarily. At the same time, a fatal problem arises that the frequency of maintenance and trouble increases unreasonably. In addition, according to the method of inclining the roller shaft of the cooling roller as disclosed in Patent Document 5, although a tensile force can be applied in the width direction of the glass ribbon G and some shrinkage in the width direction can be suppressed, Since the outer peripheral surface of the cooling roller is not different from that of a normal cooling roller, slippage occurs between the cooling roller and both ends Ga in the width direction of the glass ribbon G, and the shrinkage in the width direction of the glass ribbon G can be appropriately prevented. It does not lead to.

  In addition, a pair of roll disclosed by said patent document 6 is arranged in the upper part of the width direction both ends of the glass ribbon which flows on a horizontal surface, and the major axis direction of the pair of roll is the flow direction of a glass ribbon. Therefore, when trying to apply to the overflow down draw method, arranging the pair of rolls at both ends in the width direction of the glass ribbon so that the roll axis extends in the vertical direction, It is practically impossible. Moreover, even if the pair of rolls are arranged so that the roll shaft extends in the vertical direction, it is impossible to serve as a cooling roller in the overflow downdraw method. That is, with this pair of rolls, the intrinsic cooling action of the cooling roller cannot be performed at an appropriate vertical position of the glass ribbon, and the width of the roll depends on the relation between the shrinkage in the width direction of the glass ribbon and the cooling action. It is neglected that the thickness difference between the direction end portions and the product region is determined. Considering the above matters, even if this pair of rolls is applied to the overflow downdraw method in which the cooling roller is an essential component, it is inevitable that a great adverse effect will occur.

  In addition, the above problems are not only the case of adopting the overflow down draw method, but also adopt the common slot down draw method in that a plate-like glass ribbon is generated while flowing molten glass from the molded body. In some cases, it can occur in the same manner.

  In view of the above circumstances, the present invention provides an appropriate action to both ends in the width direction of the glass ribbon produced by flowing the molten glass from the molded body by improving the configuration of the cooling roller. The technical challenge is to ensure a sufficiently wide product area.

  The present invention, which was created to solve the above technical problem, is characterized in that the roller shafts are respectively provided at both ends in the width direction of the thicker wall than the product region of the glass ribbon produced by flowing molten glass from the molded body. In the glass plate manufacturing method including a step of preventing shrinkage in the width direction of the glass ribbon by sandwiching from both front and back sides by a pair of cooling rollers arranged to extend from the center side in the width direction of the glass ribbon to the both ends. In the step of preventing the shrinkage of the glass ribbon in the width direction, a convex portion is formed on the outer peripheral surface of the cooling roller so that the end of the glass ribbon in the width direction is caught in the width direction. Characterized by increasing the contact area. Here, the “cooling roller” has a structure that actively performs a cooling action such that the inside is hollow and a refrigerant such as water or air can flow therethrough (the same applies hereinafter).

  According to such a structure, the glass ribbon produced | generated by flowing down molten glass from a molded object flows down, the both ends of the width direction are each clamped by a pair of cooling roller, These cooling rollers Prevents the shrinkage of the glass ribbon in the width direction by catching the outer peripheral surface of the glass ribbon (both ends in the width direction of the glass ribbon). That is, if left untreated, the outer peripheral surface of the cooling roller is caught at both ends in the width direction of the glass ribbon that contracts in the width direction, so the space between the cooling roller and the glass ribbon that is in contact with the cooling roller. It is possible to appropriately prevent the shrinkage of the glass ribbon in the width direction after the slippage of the glass ribbon is suppressed. As a result, a force acts in the direction of preventing the glass ribbon from contracting in the width direction from the cooling roller, in other words, a tensile force in the width direction acts on the glass ribbon. As the thickness of the glass ribbon is reduced, the difference between the thickness of the product area and the product area is reduced, and the transition area from both ends in the width direction to the product area is also reduced. As a result, the product area of the glass ribbon is sufficiently wide. It becomes possible. Therefore, even if the amount of molten glass supplied to the molded product is decreased, it is possible to avoid the situation that the product area of the glass ribbon is narrowed, and the production amount per unit time of the glass plate is effectively increased. It becomes possible to make it.

  In this case, it is preferable that the cooling roller has a convex portion that is caught on the glass ribbon on the outer peripheral surface thereof.

  If it does in this way, the convex part formed in the outer peripheral surface of a cooling roller will be caught in the width direction both ends of a glass ribbon, and the width direction shrinkage | contraction of a glass ribbon will be prevented. And the presence of this convex part increases the contact area between the glass ribbon and the cooling roller, increases the cooling effect on the glass ribbon and promotes solidification, thereby further preventing the glass ribbon from shrinking in the width direction. Is done. Moreover, the vicinity of the center of the product area of the glass ribbon is an area where the cooling rate is inherently high, and the vicinity of both ends in the width direction of the glass ribbon is also due to the presence of a plurality of convex portions formed on the outer peripheral surface of the cooling roller. Since the cooling rate increases, the difference in cooling history that occurs between the center of the product region and the vicinity of both ends in the width direction is reduced, and this is accompanied by the fact that unnecessary thermal strain occurs in the product region. Can be avoided. Thereby, the difference of the above-mentioned cooling history becomes large and the probability of occurrence of breakage of the glass ribbon due to the occurrence of thermal strain in the product region is greatly reduced.

  Here, the said convex part can be formed in the aspect which is scattered in several places of the outer peripheral surface of a cooling roller. Specifically, the convex portions may be formed in a plurality of rows in parallel with the roller shaft and for each row, or the convex portions may be formed in a plurality of rows in parallel with the circumferential direction. A plurality of each may be formed for each row, or a plurality of the convex portions may be formed in a plurality of rows with a circumferential direction and an inclination for each row. In addition, said "circumferential direction" means the direction along the outline which the outer peripheral surface of a cooling roller and the plane orthogonal to a roller axis | shaft cross | intersect (hereinafter the same).

  If it does in this way, the some convex part formed in the aspect scattered on the outer peripheral surface of a cooling roller will be caught by the width direction both ends of a glass ribbon so that the width direction shrinkage | contraction of a glass ribbon may be prevented. At the same time, the presence of the plurality of convex portions increases the contact area with the glass ribbon and significantly increases the cooling effect. In addition, as for the arrangement | sequence state of a some convex part, it is preferable to arrange a convex part densely in the said center side so that the surface area of the glass ribbon width direction center side in the outer peripheral surface of a cooling roller may become relatively large. The shape of the convex portion is not particularly limited, and examples thereof include a conical shape, a hemispherical shape, a truncated cone shape, and a semicylindrical shape. Further, in the case where a plurality of the convex portions are formed in a plurality of rows with a circumferential direction and an inclination for each row, the contact position of the convex portions in the inclined rows with respect to the glass ribbon is the rotation of the cooling roller. Accordingly, it is preferable that the glass ribbon is formed so as to gradually move from the both ends in the width direction to the center. If it does in this way, it will become possible not only to prevent contraction of the glass ribbon in the width direction but also to apply a tensile force that increases the width direction dimension as the cooling roller rotates.

  Further, the convex portion may be a plurality of ridges or a single ridge formed on the outer peripheral surface of the cooling roller. Specifically, the convex portions may be formed in a plurality of rows in parallel with the circumferential direction and continuously for each row, or the convex portions may be in contact with the glass ribbon. You may form continuously with the circumferential direction and inclination of this roller so that it may shift to the both ends side gradually from the width direction center side of the glass ribbon with rotation of a roller.

  If it does in this way, while the multiple or one protruding item | line formed in the outer peripheral surface of a cooling roller will be caught by the width direction both ends of a glass ribbon so that the width direction shrinkage | contraction of a glass ribbon may be prevented. The presence of the plurality of ridges or one ridge increases the contact area with the glass ribbon and remarkably increases the cooling effect. Furthermore, when the ridges are formed continuously with the circumferential direction and inclination of the cooling roller, the ridges not only prevent shrinkage in the width direction of the glass ribbon as the cooling roller rotates, but also in the width direction. It is also possible to apply a tensile force that increases the size. In addition, it is preferable to form so that the surface area of the glass ribbon width direction center side in the outer peripheral surface of a cooling roller may be relatively formed in the formation state of a plurality or one protrusion.

  On the other hand, the present invention (second invention) created in order to solve the technical problem described above has both ends in the width direction that are thicker than the product region of the glass ribbon produced by flowing molten glass down from the molded body. A step of preventing shrinkage in the width direction of the glass ribbon by sandwiching the portions from both front and back sides with a pair of cooling rollers arranged such that the roller shaft extends from the center side in the width direction of the glass ribbon to both ends. In the glass plate manufacturing method including the step of preventing the shrinkage in the width direction of the glass ribbon, the diameter of the cooling roller is gradually reduced as it moves from the center side in the width direction of the glass ribbon to both ends. The taper surface formed in the above is characterized in that it contacts the transition region from the product region of the glass ribbon to the end in the width direction.

  According to such a structure, the taper surface which the outer peripheral surface of a cooling roller has is caught in the width direction both ends of a glass ribbon so that the width direction contraction of a glass ribbon may be prevented. In addition, you may make it increase the cooling effect by forming the above-mentioned convex part in this taper surface.

  In the above configuration, the roller shaft of the cooling roller may be arranged to be inclined so as to gradually move upward as it moves from the center in the width direction of the glass ribbon to both ends.

  In this way, the shrinkage of the glass ribbon in the width direction can be prevented to some extent only by inclining the roller shaft of the cooling roller in the predetermined direction. In combination with the provision of the hook portion formed of the portion and the tapered surface, it is possible to more reliably prevent the shrinkage in the width direction of the glass ribbon.

  Furthermore, in the above configuration, the width direction dimension of the glass ribbon is preferably 2000 mm or more.

  As described above, when the dimension in the width direction of the glass ribbon is a long dimension of 2000 mm or more, the above-described effects can be accurately ensured.

  As described above, according to the present invention, since the force acts in the direction of preventing the shrinkage in the width direction of the glass ribbon from the cooling roller, the plate thickness at both ends in the width direction of the glass ribbon is reduced, and the product region As a result, the transition area from the both ends in the width direction to the product area is reduced, and as a result, a sufficiently wide product area of the glass ribbon can be secured. Therefore, even if the amount of molten glass supplied to the molded product is decreased, it is possible to avoid the situation that the product area of the glass ribbon is narrowed, and the production amount per unit time of the glass plate is effectively increased. It becomes possible to make it.

It is a schematic front view which shows the principal part of the glass plate manufacturing apparatus which concerns on 1st Embodiment of this invention. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on the said 1st Embodiment. It is a cross-sectional top view which shows the state which clamped the glass ribbon with the cooling roller used with the glass plate manufacturing apparatus which concerns on the said 1st Embodiment. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on 3rd Embodiment of this invention. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on 4th Embodiment of this invention. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on 5th Embodiment of this invention. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on 6th Embodiment of this invention. It is a perspective view which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on 7th Embodiment of this invention. It is a cross-sectional top view which shows the state which clamped the glass ribbon with the cooling roller used with the glass plate manufacturing apparatus which concerns on the said 7th Embodiment. It is a schematic front view which shows the principal part of the glass plate manufacturing apparatus which concerns on 8th Embodiment of this invention. It is a cross-sectional top view of the glass ribbon for demonstrating the conventional problem. It is a cross-sectional top view of the glass ribbon for demonstrating the conventional problem.

  Hereinafter, a glass plate manufacturing apparatus for explaining a glass plate manufacturing method according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic front view showing an essential part of an apparatus for explaining a glass plate manufacturing method according to a first embodiment of the present invention, and exemplifies a process of manufacturing a glass plate by an overflow down draw method. Yes. As shown in the figure, the glass plate manufacturing apparatus 1 is a molded body that has a wedge shape that gradually becomes narrower as the cross-sectional shape (cross-sectional shape orthogonal to the paper surface) moves downward in the forming furnace 2. 3, a groove 4 having an open top is formed in the molded body 3. Then, molten glass is supplied to the groove 4 of the molded body 3, and molten glass g overflowed from the upper open portion of the groove 4 is formed on both side surfaces (side surfaces of the front and back sides of the paper surface). The plate-shaped glass ribbon G is produced | generated by flowing down, and after flowing down after joining the lower end of the molded object 3, it flows further.

  In the process in which the glass ribbon G flows down, both ends of the glass ribbon G in the width direction are sandwiched from both the front and back sides by the pair of cooling rollers 5 immediately below the formed body 3 and disposed below the both sides. Even inside the annealer 6, both end portions in the width direction of the glass ribbon G are sandwiched from the front and back sides by a pair of annealer rollers 7 arranged in a plurality of stages. Therefore, the cooling roller 5 includes a total of two pairs of a pair at the left end and a pair at the right end of the glass ribbon G between the molded body 3 and the annealer 6.

  The structure of the cooling roller 5 will be described in detail. As shown in FIG. 2, the glass ribbon G is prevented from contracting in the width direction on the outer peripheral surface of the cooling roller 5 having a roller shaft (rotation drive shaft) 5a on one end side. A plurality of convex portions 5b are formed as catching portions. In other words, the plurality of convex portions 5b have a shape that is hooked at both ends in the width direction of the glass ribbon G in a direction that prevents contraction of the glass ribbon G in the width direction. Specifically, these convex portions 5b have a semi-cylindrical shape, and both end surfaces of the semi-cylindrical convex portion 5b are flat surfaces that form steps in the circumferential direction. The arc surface of the portion 5b serves as a catching portion for preventing the glass ribbon G from contracting in the width direction.

  The semi-cylindrical convex portions 5b are formed on the outer peripheral surface of the cooling roller 5 in a plurality of rows in parallel with the roller shaft 5a and for each row. In the example shown in the figure, the convex portions 5b are formed in a plurality of rows in parallel with the circumferential direction. However, in the circumferential direction, the convex portions 5b are arranged in a staggered or inclined manner in parallel and not aligned in a row. Also good. In addition, the shape of the convex portion 5b is not limited to a semi-cylindrical shape, and may be a conical shape, a hemispherical shape, or a truncated cone shape, and may be a cubic shape or a rectangular parallelepiped shape (hereinafter referred to as a “cubic shape”). The same applies to the above embodiment).

  According to such a configuration, the glass ribbon G existing between the molded body 3 and the annealer 6 tends to shrink in the width direction. However, as shown in FIG. The width-direction both ends Ga having relatively large thicknesses are sandwiched between the pair of cooling rollers 5 from the front and back sides, and the plurality of convex portions 5b formed on the outer peripheral surfaces thereof are the both ends in the width direction of the glass ribbon G. It is in a state of being caught by Ga. As a result, a force acts from the cooling roller 5 in a direction that prevents the shrinkage of the glass ribbon G in the width direction, so that the thickness of both ends Ga in the width direction of the glass ribbon G is reduced, and the product region Gb While the difference from the plate thickness is reduced, the transition region Gc from the width direction both ends Ga to the product region Gb is also reduced, and the product region Gb of the glass ribbon G can be secured sufficiently wide.

  Moreover, the presence of the plurality of convex portions 5b formed on the outer peripheral surface of the cooling roller 5 increases the contact area between the width direction both ends Ga of the glass ribbon G and the cooling roller 5, and the cooling effect on the glass ribbon G increases. Thus, since the solidification is promoted, the shrinkage in the width direction of the glass ribbon G is more reliably prevented. In addition, the vicinity of the center of the product region Gb of the glass ribbon G is a region where the cooling rate is inherently high, and the presence of the plurality of convex portions 5b of the cooling roller 5 also in the vicinity of both ends Ga in the width direction of the glass ribbon G This increases the cooling rate. Therefore, the difference in cooling history that occurs between the vicinity of the center of the product region Gb and the vicinity of both ends Ga in the width direction is reduced, and unnecessary thermal strain is less likely to occur in the product region Gb. The probability of occurrence of G damage is greatly reduced.

  FIG. 4 is a main part perspective view showing the cooling roller 5 installed in the apparatus for explaining the glass plate manufacturing method according to the second embodiment of the present invention. The cooling roller 5 according to the second embodiment is different from the cooling roller 5 according to the first embodiment described above in that a plurality of convex portions 5c are densely formed on the outer peripheral surface of the cooling roller 5. Basically, the convex portion 5c is formed in a plurality of rows in parallel with the circumferential direction and a plurality of the projections 5c for each row. In the illustrated example, the convex portions 5c are formed in a plurality of rows in parallel with the roller shaft 5a. However, the direction of the roller shaft 5a may not be aligned in a row. Other configurations and operational effects are the same as those of the first embodiment described above, and thus description thereof is omitted.

  FIG. 5 is a main part perspective view showing a cooling roller 5 installed in an apparatus for explaining a glass plate manufacturing method according to a third embodiment of the present invention. The cooling roller 5 according to the third embodiment is different from the cooling roller 5 according to the first and second embodiments described above in that a plurality of glass rollers G on the outer peripheral surface of the cooling roller 5 in the width direction center side. The convex portions 5d are densely formed, and a plurality of convex portions 5d are roughly formed on both ends of the glass ribbon G in the width direction. If it does in this way, the cooling effect | action with respect to the width direction both ends Ga of the glass ribbon G will be performed more suitably, and it will become further advantageous when ensuring the wide product area | region Gb. Other configurations and other functions and effects are the same as those of the first embodiment described above, and thus description thereof is omitted.

  FIG. 6 is a principal perspective view showing a cooling roller 5 installed in an apparatus for explaining a glass plate manufacturing method according to a fourth embodiment of the present invention. The difference between the cooling roller 5 according to the fourth embodiment and the cooling roller 5 according to the first and second embodiments described above is that the convex portion 5e has a circumferential direction and an inclination in a plurality of rows and for each row. A plurality of each is formed, and the contact position of the convex portion 5e with the glass ribbon in the inclined row G gradually shifts from the center side in the width direction of the glass ribbon G to both end sides as the cooling roller 5 rotates. It is the point formed in. If it does in this way, with the rotation of the cooling roller 5, not only can each convex part 5e prevent the shrinkage | contraction of the width direction of the glass ribbon G but it can also provide the tensile force which increases the width direction dimension. Become. Other configurations and other functions and effects are the same as those of the first embodiment described above, and thus description thereof is omitted.

  FIG. 7 is a perspective view of a main part showing a cooling roller 5 installed in an apparatus for explaining a glass plate manufacturing method according to a fifth embodiment of the present invention. The difference between the cooling roller 5 according to the fifth embodiment and the cooling roller 5 according to the first and second embodiments (particularly the second embodiment) is that the convex portions 5f are arranged in a plurality of rows in parallel with the circumferential direction. In addition, it is a point formed continuously for each row, that is, a point where the convex portion 5e is formed in a plurality of convex shapes parallel to the circumferential direction. If it does in this way, each convex-shaped 5e will play a role as a hook part for preventing the shrinkage | contraction of the glass ribbon G in the width direction. In this case as well, the convex shapes 5e may be arranged so that the center side of the glass ribbon G is denser than its both end sides. Other configurations and operational effects are the same as those of the first embodiment described above, and thus description thereof is omitted.

FIG. 8 is a main part perspective view showing the cooling roller 5 installed in the apparatus for explaining the glass plate manufacturing method according to the sixth embodiment of the present invention. The cooling roller 5 according to the sixth embodiment is different from the cooling roller 5 according to the first and second embodiments described above in that the contact position of the convex portion 5g with the glass ribbon G depends on the rotation of the cooling roller 5. Along with this, the convex portion 5g is continuously formed with the circumferential direction and the inclination of the cooling roller 5 so as to gradually shift from the center side in the width direction of the glass ribbon G, that is, a plurality of convex portions 5g are formed. Consists of ridges, and these ridges 5g are spirally formed with the predetermined inclination. In this case, one ridge 5g may be formed in a spiral shape with the predetermined inclination. Even in this case, one or a plurality of ridges 5g serve as a catching part for preventing the glass ribbon G from contracting in the width direction.
And if it does in this way, with the rotation of the cooling roller 5, each protrusion 5g not only prevents the shrinkage | contraction of the width direction of the glass ribbon G but can also provide the tensile force which increases the width direction dimension. It becomes possible. Other configurations and other functions and effects are the same as those of the first embodiment described above, and thus the description thereof is omitted.

  FIG. 9 is a perspective view of a main part showing a cooling roller 5 installed in an apparatus for explaining a glass plate manufacturing method according to a seventh embodiment of the present invention. The cooling roller 5 according to the seventh embodiment is different from the cooling roller 5 according to the first to sixth embodiments described above in that the outer peripheral surface of the cooling roller 5 has both ends from the center in the width direction of the glass ribbon G. This is a point having a tapered surface 5h that gradually decreases in diameter as it moves to the side and is caught by the glass ribbon G. Even in this case, as shown in FIG. 10, the tapered surface 5 h of the cooling roller 5 serves as a catching portion for preventing the glass ribbon G from contracting in the width direction. According to this configuration, it is difficult to increase the surface area of the outer peripheral surface of the cooling roller 5 to increase the cooling effect, but the convex portions 5b, 5c, 5d, 5e and the convex strips 5f, 5f, If 5 g is formed, it is possible to improve the cooling effect by increasing the surface area. Other configurations and other functions and effects are the same as those of the first embodiment described above, and thus description thereof is omitted.

  FIG. 11: is a schematic front view which shows the principal part of the apparatus 1 for demonstrating the glass plate manufacturing method which concerns on 8th Embodiment of this invention. The cooling roller 5 according to the eighth embodiment is different from the cooling roller 5 according to the first embodiment shown in FIG. 1 described above in that the roller shaft 5a of the cooling roller 5 is the center in the width direction of the glass ribbon G. It is the point which is inclined and arranged so that it may gradually move upward as it moves from the side to both ends. In this case, since the cooling roller 5 rotates in contact with the flowing down glass ribbon G, when the cooling roller 5 rotates around the roller shaft 5a inclined in the predetermined direction, the glass ribbon G is moved in the width direction. A tensile force is applied. Therefore, in combination with the above-described convex portions 5b, 5c, 5d, 5e and convex strips 5f, 5g formed on the outer peripheral surface of the cooling roller 5, or the tapered surface 5h formed, the glass ribbon G The shrinkage in the width direction is more reliably prevented, and the product region Gb is further expanded.

  The inventors of the present invention have compared the glass plate manufacturing apparatus provided with the various cooling rollers described above and the glass plate manufacturing apparatus provided with the cooling roller having a smooth outer peripheral surface, after passing through the cooling roller and solidifying. Based on the glass ribbon. When this comparison is made, the glass ribbon is made with a constant flow rate of the molten glass flowing down from the molded body under the condition that the total length in the width direction of the glass ribbon is 3000 mm and the thickness of the central portion in the product area of the glass ribbon is 0.7 mm. A ribbon was generated. Further, the cooling roller has a cylindrical shape with a diameter of 50 mm and is hollow inside, and has a structure in which a coolant such as water or air flows.

  Here, as Example 1 of the present invention, as shown in FIG. 2, a cooling roller having a so-called semi-cylindrical protrusion axis parallel arrangement in which a plurality of semi-cylindrical protrusions are arranged in a plurality of rows in parallel with the roller axis on the outer peripheral surface. As a second embodiment of the present invention, as shown in FIG. 6, a so-called semi-cylindrical protrusion spiral arrangement in which a plurality of semi-cylindrical protrusions are inclined with respect to the circumferential direction and arranged in a spiral shape as shown in FIG. As a third embodiment of the present invention, a cooling roller is used to cool a so-called semi-cylindrical protrusion annular array in which a plurality of semi-cylindrical protrusions are aligned in a plurality of rows in parallel to the circumferential direction on the outer peripheral surface as shown in FIG. As Example 4 of the present invention, a so-called screw-like cooling roller having a plurality of ridges inclined on the outer circumferential surface and arranged in a spiral manner as shown in FIG. As a fifth embodiment of the present invention, as shown in FIG. Using a cooling roller of a so-called ring-shaped projections are arranged a plurality of ridges on. As a comparative example, a cooling roller having a cylindrical surface with a smooth outer peripheral surface was used. Each of these cooling rollers has a roller shaft extending in the horizontal direction as shown in FIG.

  About the glass ribbon manufactured using the cooling roller which concerns on said Examples 1-5 and a comparative example, the plate thickness of the width direction both ends, the expansion rate of the product area | region on the basis of a comparative example, and a product The thermal strain remaining in the area was measured. The results are shown in Table 1 below. In Table 1 below, the symbol Δ is slightly good, the symbol ◯ is good, the symbol ◎ is very good, and the symbol x means bad.

  According to Table 1 above, in Examples 1 to 5 of the present invention, the shrinkage in the width direction of the glass ribbon is prevented and both end portions in the width direction of the glass ribbon are efficiently cooled. It can be understood that the plate thickness is reduced and the residual strain is good. In particular, in Example 2 and Example 5, because the force that expands the width of the glass ribbon is applied, it is possible to grasp that the width of the product area of the glass ribbon is increased and the transition area is reduced. Can do.

DESCRIPTION OF SYMBOLS 1 Glass plate manufacturing apparatus 3 Forming body 5 Cooling roller 5a Roller shaft 5b, 5c, 5d, 5e Convex part 5f, 5g Convex part (convex)
5h Tapered surface G Glass ribbon Ga Both ends Gb of glass ribbon Gb Glass ribbon product area Gc Glass ribbon transition area

Claims (9)

Both ends in the width direction are thicker than the product region of the glass ribbon produced by flowing molten glass from the molded body, and the roller shafts are arranged so as to extend from the center side in the width direction of the glass ribbon to both ends. In the glass plate manufacturing method including the step of preventing the shrinkage in the width direction of the glass ribbon by sandwiching from the front and back sides with a pair of cooling rollers.
In the step of preventing the shrinkage in the width direction of the glass ribbon, the cooling roller and the glass ribbon are formed by forming, on the outer peripheral surface of the cooling roller, a convex portion in which the width direction end of the glass ribbon is hooked in the width direction. The glass plate manufacturing method characterized by increasing the contact area.   2. The glass plate manufacturing method according to claim 1, wherein a plurality of the convex portions are formed on the outer peripheral surface of the cooling roller in a plurality of rows in parallel with the roller shaft and for each row.   2. The glass plate manufacturing method according to claim 1, wherein a plurality of the protrusions are formed on the outer peripheral surface of the cooling roller in a plurality of rows in parallel with the circumferential direction and for each row.   2. The glass plate manufacturing method according to claim 1, wherein a plurality of the convex portions are formed on the outer peripheral surface of the cooling roller in a plurality of rows with a circumferential direction and an inclination for each row.   2. The glass plate manufacturing method according to claim 1, wherein the convex portions are continuously formed in a plurality of rows in parallel to the circumferential direction on each of the outer circumferential surfaces of the cooling roller and in each row. .   The convex portion is arranged on the outer circumferential surface of the roller so that the position of contact with the glass ribbon gradually shifts from the center side in the width direction of the glass ribbon to both end sides as the roller rotates. The glass plate manufacturing method according to claim 1, wherein the glass plate is continuously formed with an inclination. Both ends in the width direction are thicker than the product region of the glass ribbon produced by flowing molten glass from the molded body, and the roller shafts are arranged so as to extend from the center side in the width direction of the glass ribbon to both ends. In the glass plate manufacturing method including the step of preventing the shrinkage in the width direction of the glass ribbon by sandwiching from the front and back sides with a pair of cooling rollers.
In the step of preventing shrinkage in the width direction of the glass ribbon, a tapered surface formed on the outer peripheral surface of the cooling roller so as to gradually reduce the diameter as it moves from the center side in the width direction of the glass ribbon to both ends. A method for producing a glass plate, comprising: contacting a transition region from a product region of the glass ribbon to an end in a width direction.   The roller shaft of the cooling roller is inclined and arranged so as to gradually move upward as it moves from the center side in the width direction of the glass ribbon to both ends. The glass plate manufacturing method in any one.   The glass plate manufacturing method according to any one of claims 1 to 8, wherein a dimension of the glass ribbon in a width direction is 2000 mm or more.

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