METHOD FOR PRODUCING GLASS FILM

Abstract

Provided is a method of manufacturing a glass film, including: a forming step of forming a band-shaped glass film (1); a conveyance direction changing step of changing a conveyance direction of the band-shaped glass film (1) from a vertically downward direction to a horizontal direction by conveying the band-shaped glass film (1) along a curved conveyance path (R1); and a horizontal conveyance step of conveying the band-shaped glass film (1) in the horizontal direction along a horizontal conveyance path (R2), wherein, when some sections of the band-shaped glass film (1) are to be discarded, the method involves: a separating step of separating a discard glass part (1x) from the band-shaped glass film (1) on the horizontal conveyance path (R2); and a discarding step of discarding the separated discard glass part (1x) by causing the discard glass part (1x) to leave the horizontal conveyance path (R2) downward.

Claims

1. A method of manufacturing a glass film, comprising: a forming step of forming a band-shaped glass film by drawing the band-shaped glass film downward in a vertical direction by a down-draw method; a conveyance direction changing step of changing a conveyance direction of the band-shaped glass film from a vertically downward direction to a horizontal direction by conveying the formed band-shaped glass film along a curved conveyance path so that a front surface of the band-shaped glass film after having passed through the curved conveyance path faces upward; and a horizontal conveyance step of conveying the band-shaped glass film, which has been changed in conveyance direction, in the horizontal direction along a horizontal conveyance path, wherein, when some sections of the band-shaped glass film along a longitudinal direction are to be discarded as a discard glass part, the method involves: a separating step of separating the discard glass part from the band-shaped glass film by cutting the band-shaped glass film in a width direction on the horizontal conveyance path; and a discarding step of discarding the separated discard glass part by causing the discard glass part to leave the horizontal conveyance path downward.

2. The method of manufacturing a glass film according to claim 1, wherein an opening portion which is opened so as to be wider than an entire width of the band-shaped glass film and an opening/closing member configured to open and close the opening portion are provided below the horizontal conveyance path, wherein the discarding step is performed by opening the opening portion through use of the opening/closing member and allowing the discard glass part to pass through the opening portion, and wherein the horizontal conveyance step is performed by closing the opening portion through use of the opening/closing member and allowing the band-shaped glass film to pass on the opening/closing member.

3. The method of manufacturing a glass film according to claim 2, wherein the opening/closing member comprises: a conveyance surface portion, which is to be opposed to a back surface of the band-shaped glass film when the opening portion is closed; and a jetting port, which is formed in the conveyance surface portion, and configured to jet gas, and wherein, when the opening portion is closed through use of the opening/closing member, the gas is jetted from the jetting port toward the back surface of the band-shaped glass film passing on the conveyance surface portion so that an effective part which is present at a center of the band-shaped glass film in the width direction is conveyed under a state of floating from the conveyance surface portion.

4. The method of manufacturing a glass film according to claim 3, wherein the entire width of the band-shaped glass film is conveyed under a state of floating from the conveyance surface portion by jetting of the gas.

5. The method of manufacturing a glass film according to claim 4, wherein the jetting port comprises: a first jetting port configured to jet the gas toward the effective part; and a second jetting port configured to jet the gas toward non-effective parts which are present on outer sides of the effective part in the width direction, and wherein a region of the conveyance surface portion in which the first jetting port is formed is separated from the back surface of the band-shaped glass film with respect to a region in which the second jetting port is formed.

6. The method of manufacturing a glass film according to claim 3, wherein the opening/closing member comprises a support member configured to support the non-effective parts, which are present on outer sides of the effective part in the width direction, from a lower side when the opening portion is closed.

7. The method of manufacturing a glass film according to claim 6, wherein the support member comprises a ball roller.

8. The method of manufacturing a glass film according to claim 1, wherein, in the discarding step, the discard glass part is divided into a plurality of discard glass films and then discarded.

9. The method of manufacturing a glass film according to claim 1, wherein the band-shaped glass film is cut at a position on the horizontal conveyance path and on downstream of a position of performing the discarding step by laser light in a longitudinal direction along a boundary between the effective part, which is present at the center of the band-shaped glass film in the width direction, and each of the non-effective parts, which are present on outer sides of the effective part in the width direction.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0035] FIG. 1 is a schematic vertical sectional side view for illustrating a method of manufacturing a glass film according to a first embodiment of the present invention.

[0036] FIG. 2 is a plan view for illustrating a horizontal conveyance step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0037] FIG. 3 is a vertical sectional front view for illustrating an A-A cross section in FIG. 2.

[0038] FIG. 4 is a side view for illustrating the horizontal conveyance step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0039] FIG. 5a is a schematic view for illustrating a separating step and a discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0040] FIG. 5b is a schematic view for illustrating the separating step and the discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0041] FIG. 5c is a schematic view for illustrating the separating step and the discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0042] FIG. 5d is a schematic view for illustrating the separating step and the discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0043] FIG. 6 is a side view for illustrating the separating step and the discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0044] FIG. 7 is a side view for illustrating the separating step and the discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0045] FIG. 8 is a side view for illustrating the separating step and the discarding step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0046] FIG. 9 is a side view for illustrating the method of manufacturing a glass film according to the first embodiment of the present invention.

[0047] FIG. 10 is a side view for illustrating the horizontal conveyance step in the method of manufacturing a glass film according to the first embodiment of the present invention.

[0048] FIG. 11 is a plan view for illustrating a horizontal conveyance step in a method of manufacturing a glass film according to a second embodiment of the present invention.

[0049] FIG. 12 is a vertical sectional front view for illustrating the horizontal conveyance step in the method of manufacturing a glass film according to the second embodiment of the present invention.

[0050] FIG. 13 is a plan view for illustrating a horizontal conveyance step in a method of manufacturing a glass film according to a third embodiment of the present invention.

[0051] FIG. 14 is a vertical sectional front view for illustrating the horizontal conveyance step in the method of manufacturing a glass film according to the third embodiment of the present invention.

[0052] FIG. 15 is a plan view for illustrating a horizontal conveyance step in a method of manufacturing a glass film according to a fourth embodiment of the present invention.

[0053] FIG. 16 is a vertical sectional front view for illustrating the horizontal conveyance step in the method of manufacturing a glass film according to the fourth embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

[0054] Now, with reference to the accompanying drawings, description is made of a method of manufacturing a glass film according to embodiments of the present invention.

First Embodiment

[0055] First, description is made of a method of manufacturing a glass film according to a first embodiment of the present invention. It is preferred that this embodiment be applied to a case in which a band-shaped glass film to be formed has a thickness of less than 50 m.

[0056] As illustrated in FIG. 1, the method of manufacturing a glass film according to the first embodiment comprises a forming step, a conveyance direction changing step, a horizontal conveyance step, a cutting and removing step, and a winding step. In the forming step, a band-shaped glass film 1 is formed while being drawn downward in a vertical direction by an overflow down-draw method. In the conveyance direction changing step, a conveyance direction of the band-shaped glass film 1 is changed from a vertically downward direction to a horizontal direction by conveying the formed band-shaped glass film 1 along a curved conveyance path R1. In the horizontal conveyance step, the band-shaped glass film 1, which has been changed in conveyance direction, is conveyed in the horizontal direction along a horizontal conveyance path R2. In the cutting and removing step, non-effective parts 1a are cut and removed from the band-shaped glass film 1 being conveyed in the horizontal direction. In the winding step, the band-shaped glass film 1 having the non-effective parts 1a removed therefrom and comprising only an effective part 1b is wound up into a roll around a winding core 2 to be formed into a glass roll 3.

[0057] [Forming Step]

[0058] For the forming step, there are mainly used a forming trough 4 and roller pairs 6. The forming trough 4 has a wedge shape. The roller pairs 6 are arranged in a plurality of stages along an up-and-down direction, and are capable of sandwiching, from both front and back sides, a glass ribbon 5 flowing down from the forming trough 4.

[0059] The forming trough 4 comprises an overflow groove 4a, a pair of side surface portions 4b and 4b, and a lower end portion 4c. The overflow groove 4a is formed in a top portion of the forming trough 4 for allowing a molten glass 7 to flow thereinto. The pair of side surface portions 4b and 4b are configured to allow the molten glass 7 having flowed out from the overflow groove 4a to both sides to flow down. The lower end portion 4c is configured to merge and integrate the molten glass 7 having flowed down along the side surface portions 4b and 4b. The forming trough 4 is capable of continuously producing the glass ribbon 5 from the molten glass 7 having merged and integrated at the lower end portion 4c.

[0060] The roller pairs 6 arranged in a plurality of stages along the up-and-down direction comprise a cooling roller pair 6a, annealer roller pairs 6b, and a support roller pair 6c in the state order from an upper stage. The roller pairs 6 are each capable of sandwiching parts of the glass ribbon 5 on one side and another side in a width direction of the glass ribbon 5, which are to be later formed into the non-effective parts la of the band-shaped glass film 1.

[0061] The cooling roller pair 6a is a roller pair configured to suppress contraction of the glass ribbon 5 in the width direction by sandwiching the glass ribbon 5 directly below the forming trough 4. The annealer roller pairs 6b are each a roller pair configured to guide the glass ribbon 5 downward, which is to be annealed to a temperature equal to or less than a strain point in an annealing furnace 8. The annealer roller pairs 6b sandwich the glass ribbon 5 in some cases, or only restrict rocking of the glass ribbon 5 in the thickness direction without sandwiching the glass ribbon 5 in some cases. The support roller pair 6c is a roller pair which is configured to support the glass ribbon 5 having been reduced in temperature to a temperature close to a room temperature in a cooling chamber (not shown) arranged below the annealing furnace 8. Further, the support roller pair 6c is configured to determine a speed of pulling down the glass ribbon 5 (drawing speed).

[0062] The glass ribbon 5 having passed through the roller pairs 6 which are arranged in a plurality of stages along the up-and-down direction is formed into the band-shaped glass film 1. The band-shaped glass film 1 is formed so as to have a thickness which is sufficient to give flexibility to the band-shaped glass film 1. The band-shaped glass film 1 comprises the effective part 1b and the pair of non-effective parts 1a. The effective part 1b is present at a center in the width direction (direction perpendicular to the drawing sheet of FIG. 1) and later forms a finished product. The pair of non-effective parts 1a are present on outer sides of the effective part 1b in the width direction and are to be removed. Further, in the non-effective parts 1a, at parts positioned at end portions of the band-shaped glass film 1 in the width direction, there are formed edge portions 1aa each having a thickness larger than those of other parts.

[0063] In this embodiment, the band-shaped glass film 1 is formed through use of the overflow down-draw method. However, as a matter of course, the band-shaped glass film 1 may be formed through use of, for example, a slot down-draw method or a re-draw method.

[0064] [Conveyance Direction Changing Step]

[0065] For the conveyance direction changing step, a roller conveyor 9 is used. The roller conveyor 9 is formed of a plurality of rollers 9a arranged in parallel with each other. The roller conveyor 9 conveys the band-shaped glass film 1 along the curved conveyance path R1 while supporting the band-shaped glass film 1 from a back surface 1c side, to thereby change the conveyance direction so that a front surface 1d of the band-shaped glass film 1 having passed through the curved conveyance path R1 faces upward.

[0066] [Horizontal Conveyance Step]

[0067] For the horizontal conveyance step, there are used a belt conveyor 10, three divided plate-shaped bodies 11, 12, and 13, a belt conveyor 14, and a belt conveyor 15, which are arranged in the stated order from an upstream side along the horizontal conveyance path R2.

[0068] The belt conveyor 10 is capable of jetting a gas G (for example, air) with respect to the back surface 1c of the band-shaped glass film 1, and the band-shaped glass film 1 is conveyed on the belt conveyor 10 under a state in which only a center thereof in the width direction (mainly the effective part 1b) floats. The belt conveyor 10 comprises a belt 10a and a gas jetting device (not shown). The belt 10a has an endless shape, and is configured to convey non-floating portions (mainly the non-effective parts 1a) of the band-shaped glass film 1. The gas jetting device is arranged on an inner peripheral side of the belt 10a, and is configured to jet the gas G upward. The belt 10a has a large number of fine through holes (not shown), and the gas G having been jetted from the gas jetting device passes through the through holes to reach the back surface 1c of the band-shaped glass film 1. The gas jetting device arranged on the inner peripheral side of the belt 10a is arranged along the center of the belt 10a in the width direction.

[0069] As illustrated in FIG. 2 and FIG. 3, the three divided plate-shaped bodies 11, 12, and 13 each comprise a conveyance surface portion 16 to be opposed to the back surface 1c of the band-shaped glass film 1. The conveyance surface portion 16 has a large number of jetting ports 16a. The jetting ports 16a are configured to jet the gas G (for example, air) toward the effective part 1b of the band-shaped glass film 1 passing on the conveyance surface portion 16. Moreover, the conveyance surface portion 16 comprises a plurality of ball rollers 16b serving as a support member configured to support the non-effective parts 1a of the band-shaped glass film 1 from a lower side. With this, during the horizontal conveyance step, under a state in which the effective part 1b floats from the conveyance surface portion 16 by the pressure of the gas G and in which the non-effective parts 1a are supported by the ball rollers 16b, the band-shaped glass film 1 is conveyed so as to pass on the plate-shaped bodies 11, 12, and 13.

[0070] The conveyance surface portion 16 is formed into a rectangular shape which is wider than an entire width of the band-shaped glass film 1. The large number of jetting ports 16a communicate with a space 17 defined inside each of the plate-shaped bodies 11, 12, and 13. The jetting ports 16a are each capable of jetting the gas G, which is supplied from a fluid compressing device (for example, an air compressor) to the space 17. The plurality of ball rollers 16b are arranged in a state of being arrayed in two rows along the longitudinal direction of the band-shaped glass film 1. The ball rollers 16b each comprise a load ball 16ba, a hole portion 16bb, and support balls 16bc. The load ball 16ba has a spherical shape, and is configured to directly support the non-effective part 1a. The hole portion 16bb is configured to receive the load ball 16ba inserted thereinto. The support balls 16bc are configured to support the load ball 16ba so that the load ball 16ba is rotatable in the hole portion 16bb.

[0071] As illustrated in FIG. 4, among the three divided plate-shaped bodies 11, 12, and 13, the plate-shaped body 12 serves as an opening/closing member configured to open and close an opening portion 18 defined between the plate-shaped body 11 and the plate-shaped body 13. The opening portion 18 is defined below the horizontal conveyance path R2, and is opened so as to be wider than the entire width of the band-shaped glass film. The plate-shaped body 12 is connected to the plate-shaped body 11, which is arranged on upstream of the plate-shaped body 12 along the horizontal conveyance path R2, through intermediation of a coupling member 19 (for example, a hinge). The coupling member 19 comprises a first plate 19a, a second plate 19b, and a shaft portion 19c. The first plate 19a is fixed to the plate-shaped body 11. The second plate 19b is fixed to the plate-shaped body 12. The shaft portion 19c is configured to hold both the plates 19a and 19b and serves as a swing shaft for the plates 19a and 19b. The shaft portion 19c extends along the width direction of the band-shaped glass film 1.

[0072] With this configuration, the plate-shaped body 12 swings about the shaft portion 19c of the coupling member 19 so as to be movable between an initial position (position indicated by the solid line in FIG. 4) and a swing position (position indicated by the two-dot chain line in FIG. 4), thereby opening and closing the opening portion 18 along with the movement. In the method of manufacturing a glass film according to this embodiment, through the opening and closing of the opening portion 18 by the plate-shaped body 12, the operation of the horizontal conveyance step and an operation including a separating step and a discarding step, which are described later, can be switched.

[0073] When the plate-shaped body 12 is brought to the initial position to close the opening portion 18, as described above, under the state in which the effective part 1b floats by the gas G and the non-effective parts 1a are supported by the ball rollers 16b, the band-shaped glass film 1 is allowed to pass on the plate-shaped body 12 so that the horizontal conveyance step is performed. In contrast, when the plate-shaped body 12 is brought to the swing position to open the opening portion 18, under a state in which jetting of the gas G and the support by the ball rollers 16b are cancelled, the separating step and the discarding step are performed.

[0074] [Separating Step and Discarding Step]

[0075] Now, description is made of an outline of the separating step and the discarding step.

[0076] In FIG. 5a to FIG. 5d, illustration is given of an outline of the separating step and the discarding step. A leading portion 1xa of a discard glass part 1x illustrated in FIG. 5a is first separated from a rearmost portion G1a of a preceding band-shaped glass film 1 (G1) as illustrated in FIG. 5b. With this, the separating step is started. After that, as illustrated in FIG. 5c, the discard glass part 1x is continuously divided into a plurality of discard glass films 1xx. Moreover, along with the start of the discarding step, the discard glass films 1xx are sequentially caused to leave the horizontal conveyance path R2 downward so that the discard glass films 1xx are discarded. Finally, as illustrated in FIG. 5d, a rearmost portion 1xb of the discard glass part 1x is separated from a leading portion G2a of a subsequent band-shaped glass film 1 (G2). With this, the entire length of the discard glass part 1x is separated from the band-shaped glass film 1, and the separating step is completed. Moreover, the discard glass film 1xx including the rearmost portion 1xb of the discard glass part 1x is discarded, and the discarding step is completed.

[0077] Now, with reference to FIG. 6 to FIG. 8, detailed description is made of the separating step and the discarding step.

[0078] First, as a preparation for the separating step and the discarding step, a cutting start point 20 serving as a start point for cutting is formed on the front surface 1d side of the band-shaped glass film 1. The cutting start point 20 is formed at a position on upstream of the plate-shaped body 12 on the conveyance path for the band-shaped glass film 1. The position of forming the cutting start point 20 may be on the horizontal conveyance path R2, or may be on the curved conveyance path R1. Moreover, the cutting start point 20 may be, for example, a scribe line formed along the width direction of the band-shaped glass film 1 through use of a wheel cutter, or a scratch formed in the edge portion 1aa of the band-shaped glass film 1 along the width direction through use of a grinder. A plurality of cutting start points 20 are successively formed at intervals along the longitudinal direction of the band-shaped glass film 1.

[0079] Next, as illustrated in FIG. 6, when a cutting start point 20 (20a) which is positioned on most downstream on the horizontal conveyance path R2 among the plurality of cutting start points 20 reaches the plate-shaped body 12, the plate-shaped body 12 is moved from the initial position to the swing position to open the opening portion 18. In this embodiment, the opening portion 18 is opened after the cutting start point 20 (20a) has reached the plate-shaped body 12. However, the opening portion 18 may be opened before the cutting start point 20 (20a) reaches the plate-shaped body 12. With this, the band-shaped glass film 1 stretched between the plate-shaped body 11 and the plate-shaped body 13 is flexed downward by its own weight. Then, along with this flexure, the portion at which the cutting start point 20 (20a) is formed is curved so that the front surface 1d side thereof protrudes. With this, as illustrated in FIG. 7, the band-shaped glass film 1 is cut in the width direction by bending stress with the cutting start point 20 (20a) as a start point. Then, along with the cutting of the band-shaped glass film 1, the leading portion 1xa of the discard glass part 1x is separated from the rearmost portion G1a of the preceding band-shaped glass film 1 (G1).

[0080] After the band-shaped glass film 1 has been cut with the cutting start point 20 (20a) as a start point, every time each of the plurality of cutting start points 20 subsequent to the cutting start point 20 (20a) reaches the opening portion 18 having already been opened, the discard glass part 1x is repeatedly cut in the width direction with the cutting start points 20 as start points. Along with this action, as illustrated in FIG. 8, the discard glass part 1x is divided into a plurality of discard glass films 1xx, and the discard glass films 1xx are caused to fall from the horizontal conveyance path R2 and pass through the opening portion 18, thereby discarding the discard glass films 1xx. The discarding of the discard glass films 1xx is continuously performed until the discard glass film 1xx including the rearmost portion 1xb of the discard glass part 1x is discarded. With the operations described above, the separating step and the discarding step are completed.

[0081] After the separating step and the discarding step have been completed, as illustrated in FIG. 9, at the time point at which the leading portion G2a of the band-shaped glass film 1 (G2) connected to the rearmost portion 1xb of the discard glass part 1x reaches the plate-shaped body 12, the plate-shaped body 12 is moved to return from the swing position to the initial position, and closing of the opening portion 18 is started. After the plate-shaped body 12 returns to the initial position, the opening portion 18 is closed by the plate-shaped body 12 by the returning of the plate-shaped body 12. Then, as illustrated in FIG. 10, the horizontal conveyance step of conveying the band-shaped glass film 1 (G2) which is subsequent to the discard glass part 1x along the horizontal conveyance path R2 is performed.

[0082] [Cutting and Removing Step]

[0083] As illustrated in FIG. 1, in the cutting and removing step, at a position on the horizontal conveyance path R2 and on downstream of the position of performing the discarding step, the non-effective parts la are cut and removed from the band-shaped glass film 1 through use of a laser cutting method. For the cutting and removing step, there are used a laser irradiator 21 and a refrigerant jetting device 22, which are fixed and installed at certain points above the belt conveyor 14. The laser irradiator 21 is configured to continuously irradiate the band-shaped glass film 1 passing therebelow with a laser light 21a along a boundary between the effective part 1b and each of the non-effective parts 1a. The refrigerant jetting device 22 is configured to continuously jet a refrigerant 22a (for example, mist-like water) with respect to the part of the band-shaped glass film 1 having been irradiated with the laser light 21a.

[0084] With this, a thermal stress is generated in the band-shaped glass film 1 due to a temperature difference between the part having been heated by the laser light 21a and the part having been cooled by the refrigerant 22a. Further, due to the thermal stress, a cut part (part at which the effective part 1b and the non-effective part 1a are separated from each other) is continuously formed along the boundary between the effective part 1b and the non-effective part 1a. In such a manner, the band-shaped glass film 1 is continuously cut along the longitudinal direction. In this embodiment, the band-shaped glass film 1 is cut by the laser cutting method. However, the band-shaped glass film 1 may be cut by a laser fusing method, or a so-called peeling method of simultaneously performing laser fusion and removal of an end portion formed along with the fusion as a string-shaped object to be peeled off.

[0085] The band-shaped glass film 1 having the non-effective parts 1a cut and removed therefrom (band-shaped glass film 1 comprising only the effective part 1b) is moved from the belt conveyor 14 to the belt conveyor 15. Meanwhile, the non-effective parts 1a having been removed from the band-shaped glass film 1 are not moved to the belt conveyor 15. The non-effective parts 1a are separated downward from the conveyance path for the band-shaped glass film 1, and are thereafter discarded.

[0086] [Winding Step]

[0087] For the winding step, there are mainly used the winding core 2 and a sheet roll 23. In the winding step, the band-shaped glass film 1 having been conveyed from the belt conveyor 15 is superposed on a protection sheet 23a that is continuously fed out from the sheet roll 23. After that, the band-shaped glass film 1 is wound up into a roll around the winding core 2 to be formed into the glass roll 3. With this, all of the steps of the method of manufacturing a glass film according to this embodiment are completed.

[0088] Now, description is made of a method of manufacturing a glass film according to another embodiment of the present invention. In the description of the another embodiment, components which are already described in the above-mentioned first embodiment are denoted by the same reference symbols in the drawings referred to in the description of the another embodiment. Thus, redundant description thereof is omitted, and only differences from the first embodiment are described. In second to fourth embodiments described below, respective methods of manufacturing a glass film are different from that of the above-mentioned first embodiment in that the configuration of the plate-shaped bodies 11, 12, and 13 is different.

Second Embodiment

[0089] As illustrated in FIG. 11 and FIG. 12, in the method of manufacturing a glass film according to the second embodiment, in the conveyance surface portion 16 of each of the plate-shaped bodies 11, 12, and 13, a large number of jetting ports 16a which are configured to jet the gas G toward the non-effective parts 1a of the band-shaped glass film 1 are formed in the region in which the plurality of ball rollers 16b are provided in the above-mentioned first embodiment. With this, in this embodiment, during the horizontal conveyance step, under a state in which the entire width of the band-shaped glass film 1 floats from the conveyance surface portion 16 by the pressure of the gas G, the band-shaped glass film 1 is conveyed so as to pass on the plate-shaped bodies 11, 12, and 13. It is preferred that this embodiment be applied to the case in which, similarly to the above-mentioned first embodiment, the band-shaped glass film 1 to be formed has a thickness of less than 50 m.

Third Embodiment

[0090] As illustrated in FIG. 13 and FIG. 14, in the method of manufacturing a glass film according to the third embodiment, in the conveyance surface portion 16 of each of the plate-shaped bodies 11, 12, and 13, first jetting ports 16aa configured to jet the gas G toward the effective part 1b and second jetting ports 16ab configured to jet the gas G toward the non-effective parts 1a are formed. Further, in the conveyance surface portion 16, the region in which the first jetting ports 16aa are formed is arranged so as to be separated from the back surface of the band-shaped glass film with respect to the region in which the second jetting ports 16ab are formed. With this, in this embodiment, during the horizontal conveyance step, under the state in which the entire width of the band-shaped glass film 1 floats from the conveyance surface portion 16 by the pressure of the gas G and in which the effective part 1b is separated from the conveyance surface portion 16 with respect to the non-effective parts 1a, the band-shaped glass film 1 is conveyed so as to pass on the plate-shaped bodies 11, 12, and 13. It is preferred that this embodiment be applied to the case in which the band-shaped glass film 1 to be formed has a thickness equal to or more than 50 m.

Fourth Embodiment

[0091] As illustrated in FIG. 15 and FIG. 16, in the method of manufacturing a glass film according to the fourth embodiment, in the conveyance surface portion 16 of each of the plate-shaped bodies 11, 12, and 13, the region in which the plurality of ball rollers 16b are provided is arranged above the region in which the large number of jetting ports 16a are formed. With this, in this embodiment, during the horizontal conveyance step, under the state in which the effective part 1b floats further above the conveyance surface portion 16 by the pressure of the gas G in comparison with the above-mentioned first embodiment and in which the non-effective parts 1a are supported by the ball rollers 16b, the band-shaped glass film 1 is conveyed so as to pass on the plate-shaped bodies 11, 12, and 13. It is preferred that this embodiment be applied to the case in which the band-shaped glass film 1 to be formed has a thickness equal to or more than 50 m.

[0092] A method of manufacturing a glass film according to the present invention is not limited to the modes described in the above-mentioned embodiments. For example, in each of the above-mentioned embodiments, the plate-shaped body 12 is used as the opening/closing member configured to open and close the opening portion 18. However, a belt conveyor may be used as the opening/closing member. In this case, for example, in order to perform the horizontal conveyance step under a state in which a conveyance surface of the belt conveyor is in a posture along a horizontal plane (conveyance surface of the belt conveyor is in a posture of being parallel to the horizontal direction) and perform the separating step and the discarding step under a state in which the conveyance surface is in a posture of an inclined plane that is inclined with respect to the horizontal plane, a belt conveyor which is capable of being changed in posture is used.

[0093] Moreover, in each of the above-mentioned embodiments, the roller conveyor 9 is used for the conveyance direction changing step, but the present invention is not limited to this configuration. The conveyance direction changing step may be performed without use of the roller conveyor 9, and may be performed by conveying the band-shaped glass film, which is being conveyed downward in the vertical direction, directly to the belt conveyor 10 (horizontal conveyance path R2). In this case, the band-shaped glass film on the curved conveyance path R1 is brought into a state of being curved in conformity with the curved conveyance path R1 under a state of not being supported by any external object.

REFERENCE SIGNS LIST

[0094] 1 band-shaped glass film [0095] 1a non-effective part [0096] 1b effective part [0097] 1c back surface [0098] 1d front surface [0099] 1x discard glass part [0100] 1xx discard glass film [0101] 12 plate-shaped body [0102] 16 conveyance surface portion [0103] 16a jetting port [0104] 16aa first jetting port [0105] 16ab second jetting port [0106] 16b ball roller [0107] 18 opening portion [0108] G gas [0109] R1 curved conveyance path [0110] R2 horizontal conveyance path