JP4629007B2 - Air plate for sheet material conveyance and sheet material conveyance device - Google Patents

Description

  The present invention is an air table for transporting a thin plate material that supports a thin plate material such as a large thin glass substrate used in a flat panel display (FPD) such as a liquid crystal display (LCD) panel or a plasma display (PDP) in a non-contact manner. The present invention also relates to a thin plate material conveying apparatus including the same.

  Since glass substrates of flat panel displays such as liquid crystal displays and plasma displays have a significant effect on quality even with slight scratches and dust, the glass substrate surface should not be scratched or foreign matter adhered when transporting such glass substrates. In addition, it is required to smoothly convey the glass substrate along a predetermined conveying surface while holding the glass substrate in a shape close to a flat surface.

  On the other hand, in the liquid crystal display, the size of the glass substrate is becoming larger, and for example, in the 8th generation, the thickness is very thin, about 0.5 to 0.7 mm, compared to the size of W2200 mm × L2500 mm. When the glass substrate is transported horizontally, not only the outer peripheral end portion but also the inner portion of the glass substrate is supported, the central portion droops greatly.

  Thus, the glass substrate transport device is devised to support the glass substrate as uniformly as possible over the entire surface and transport the glass substrate while maintaining a shape close to a flat surface.

  For example, a transport apparatus is known in which a plurality of rollers are installed at an appropriate pitch in the transport direction of the transport surface and in the width direction perpendicular to the transport direction, and the glass substrate is driven from below by the plurality of rollers.

  However, the conveyance device that supports and drives the glass substrate from below with a plurality of rollers increases the number of parts such as rollers, shafts, and bearings and the number of assembling steps as the glass substrate increases in size. There is. Furthermore, there is a problem that maintenance cost increases due to an increase in the number of parts. In addition, the glass substrate is repeatedly contacted with the roller and separated from the roller to generate vibration, which may cause noise and dust generation, and the surface of the glass substrate may be lost. There is a problem that it is more likely to occur. In addition, due to the lengthening of the shaft, the rotation accuracy of the roller is lowered due to the decrease in the straightness of the shaft and the increase in the amount of deflection. In this respect, noise and dust are easily generated, and the surface of the glass substrate is easily damaged. There is also a problem.

  On the other hand, there is known a transport device that transports in a non-contact manner by driving with a pressure of air while floating a glass substrate using an air table in which a large number of air supply holes are formed on an upper surface plate (for example, Patent Document 1). 2, 3).

  In addition, an air table is installed near the center of the glass substrate in the width direction to prevent the center of the glass substrate from sagging, and both ends of the glass substrate in the width direction perpendicular to the transport direction are supported by rollers from below. A transfer device that drives a glass substrate is known (see, for example, Patent Documents 4 and 5).

  In addition, as an upper surface plate of an air table, a punching metal or the like that is easily available at low cost is often used.

  However, the hole diameter of the punching metal is usually about 1 to 10 mm, and if a sufficient amount of air is injected from the air supply hole of such a size to levitate the glass substrate, the air flow rate becomes excessively high. There is a problem that it ends up.

  More specifically, the glass substrate transfer device is often used in a clean room. The flow rate of clean air in the clean room is about 500 mm / sec, whereas the diameter is about 1 to 10 mm. Since the flow velocity of the air injected from the air supply holes is about 900 to 2500 mm / sec, which is significantly faster than the descending air flow of clean air in the clean room, there is a problem that the air in the clean room is disturbed. In addition, due to such air turbulence, foreign substances such as dust may easily adhere to the glass substrate. In order to suppress the turbulence of the air in the clean room, it is preferable to suppress the flow rate of the air injected from the air table to be smaller than the flow rate of the downflow of the clean air in the clean room.

  On the other hand, the air table which comprised the upper surface board with porous materials, such as a ceramic, is known (for example, refer patent document 6).

  There is also known an air table in which a porous plate material such as resin or ceramic, cloth, paper, or the like is installed under an upper surface plate such as punching metal (for example, see Patent Document 7).

  Thus, by injecting air through a porous plate material, cloth, paper, or the like, the air jetted from the air supply holes has a uniform airflow distribution, and the turbulence of the airflow is suppressed.

JP-A-10-139160 JP-A-11-268830 Japanese Patent Laid-Open No. 11-268831 JP 2003-63643 A JP 2005-29359 A JP 2004-307152 A JP 2004-345744 A

  However, an air table having a top plate made of a porous material such as ceramic or an air table in which a porous plate material such as resin or ceramic is placed under the top plate such as punching metal is actually made of resin, ceramic or the like. Since the airflow resistance of the porous plate material is large, there is a problem that the flow rate of air that can be ejected is small and the turbulence of the air in the clean room is suppressed, but the flying height is small.

  More specifically, the flying height of the glass substrate (the gap between the glass substrate and the upper surface of the air table) is as small as about 0.1 to 0.5 mm, and can reliably prevent contact between the glass substrate and the air table. There is a problem that it is difficult. In addition, since the flying height is small, when a plurality of air tables are installed side by side, it is necessary to match the heights of these upper surfaces with such high accuracy, and there is a problem that the installation work is complicated and the installation man-hour is large. In order to reliably prevent the glass substrate and the air table from contacting each other, the flying height is preferably 1 mm or more.

  Also, air tables with cloth, paper, etc. installed under the top plate such as punching metal have problems with the durability of cloth, paper, etc., and the problem that cloth and paper can be a new source of dust generation. There is also.

  The present invention has been made in view of the above problems, and includes an air table for transporting a thin plate material that can obtain a large floating amount of the thin plate material while suppressing air turbulence in a clean room, and the air table. It aims at providing a thin plate-shaped material conveyance apparatus.

  The present invention relates to an upper surface plate in which a plurality of air supply holes for supplying gas to the lower surface of a thin plate material are formed, a porous film installed in contact with the upper surface plate under the upper surface plate, The object is achieved by an air table for transporting a thin plate material having a mesh member installed to support the film from below.

  The present invention also provides an upper plate in which a plurality of air supply holes for supplying gas to the lower surface of the thin plate material are formed, a porous film installed under the upper plate, the porous film, and the upper surface. The above object is achieved by a thin plate material conveying air table having a mesh member sandwiched between plates.

  In these thin plate material conveying air tables, air is injected from the air supply holes of the upper surface plate through the porous film, so that the turbulence of the airflow is suppressed similarly to the air table including the porous plate material, and the upper surface plate Air is injected from the air supply holes. Further, since the thin porous film has a lower airflow resistance than the porous plate material, the flow rate of the air injected from the air supply holes can be increased as compared with the case where the porous plate material is used. Therefore, a large flying height can be obtained while suppressing air turbulence in the clean room. Furthermore, the porous film is not a source of dust generation.

  In addition, when the porous film is placed under the upper surface plate and in contact with the upper surface plate, the portion of the upper surface plate where the air supply holes are not formed is in close contact with the porous film, and the opening area of the porous film is reduced accordingly. Therefore, the flow rate of the air injected from the air supply holes of the top plate is suppressed, but the pressure of the air below the porous film can be made relatively high, so the pressure of the air injected from the air supply holes is also relatively high. This can provide a large flying height. That is, this configuration is suitable for a high pressure type air table that obtains a large flying height by injecting air having a relatively high pressure onto a thin plate material.

  In this configuration, the mesh member is installed under the porous film so as to support the porous film from below, and the thin porous film is reinforced with the mesh member, so that the durability of the porous film is enhanced. be able to.

  On the other hand, when the mesh member is sandwiched between the porous film and the upper surface plate, an air passage is formed between the portion of the upper surface plate where the air supply holes are not formed and the porous film. The substantial opening area of the film is accordingly large. Therefore, although the pressure of the air injected from the air supply hole is reduced, the flow rate of the air injected from the air supply hole can be further increased, and in this case, a large flying height can be obtained. That is, this configuration is suitable for a large flow rate type air table that obtains a large flying height by injecting air having a relatively large flow rate onto a thin plate material.

  In addition, since the porous film has a higher pressure on the lower side than the upper side, the porous film is urged to protrude into the air supply holes of the upper surface plate, but the mesh member is placed between the porous film and the upper surface plate. Therefore, the projection of the porous film into the air supply holes is suppressed. That is, also in this case, the thin porous film is reinforced with the mesh member, and the durability of the porous film can be enhanced.

  Both the lower position where the mesh member is installed under the porous film so as to support the porous film from below and the upper position where the mesh member is sandwiched between the porous film and the upper plate are installed. It is good also as a structure which can be installed in this position.

  By doing so, it is possible to easily change the configuration from the high pressure type air table as described above to the large flow rate type air table and vice versa.

  In addition, a support plate in which a vent hole is formed at a position communicating with the air supply hole of the upper surface plate is installed under the upper surface plate, and the porous film and the mesh member are sandwiched between the upper surface plate and the support plate. It is good also as an installed configuration.

  This configuration is simple and the installation work of the porous film and the mesh member is easy. Moreover, the operation | work which changes the installation position of a mesh member from an upper position to a lower position installation as mentioned above, and the reverse operation | work are easy.

  Moreover, this invention achieves the said objective by the thin plate-shaped material conveyance apparatus provided with the air table for thin-plate-shaped material conveyance in any one of the above.

  ADVANTAGE OF THE INVENTION According to this invention, the thin plate-shaped material conveyance air table provided with this can be implement | achieved and the air table for thin plate-shaped material which can obtain the big floating amount of a thin plate-shaped material, suppressing the disturbance of the air in a clean room.

  Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

  As shown in FIG. 1, a thin plate material transport apparatus 10 according to the first embodiment of the present invention includes, for example, a large LCD glass substrate (thin plate material) 12 by a thin plate material transport air table 14. It is supported and conveyed in a non-contact manner, and has a feature in the structure of the air table 14 for conveying the thin plate material.

  As shown in FIG. 2, the thin plate material conveying air table 14 includes an upper surface plate 18 in which a plurality of air supply holes 16 for supplying gas to the lower surface of the glass substrate 12 are formed, and an upper surface plate 18. It has a porous film 20 installed in contact with the upper surface plate 18 below and a mesh member 22 installed so as to support the porous film 20 from below.

  Also, below the top plate 18, a support plate 26 in which a vent hole 24 is formed at a position communicating with the air supply hole 16 of the top plate 18 is installed, and the porous film 20 and the mesh member 22 are connected to the top plate 18. It is sandwiched between the support plate 26 and installed.

  Note that a plurality (four in the first embodiment) of the thin plate material conveying air tables 14 are provided in the width direction perpendicular to the conveying direction of the glass substrate 12.

  The thin plate material conveying air table 14 is a substantially rectangular parallelepiped box.

  The upper surface plate 18 constitutes the upper surface portion of the box. Specifically, the upper surface plate 18 is a plate material having a thickness of 0.5 to 3 mm. As the material of the face plate 18, stainless steel, aluminum, various alloys, or the like can be used. As shown in FIG. 3, the air supply holes 16 have a circular shape with a diameter of 6 to 50 mm, and are formed with a large number of pitches (pitch between centers) of 8 to 100 mm.

  The upper surface plate 18 is provided with a side wall portion 28 that protrudes downward along the outer periphery thereof. The top plate 18 and the side wall portion 28 are fitted to the outside of the side wall portion 30A of the base 30 of the box body that opens upward, and are fastened by the side wall portion 30A and the fastening member 32 at the side wall portion 28.

  The porous film 20 has a thickness of 0.1 to 3 mm. As schematically shown in FIG. 4, a large number of fine pores having an average pore diameter of 10 to 50 μm are formed in the porous film 20 with a porosity of 20 to 40%. As a material of the porous film 20, specifically, various resins such as polyethylene and polyolefin can be used. The porous film 20 is sandwiched and fixed between the upper end of the side wall portion 30A of the base portion 30 and the outer peripheral portion of the top plate 18 at the outer peripheral portion.

  The mesh member 22 has a configuration in which a wire-like or thread-like member having a wire diameter of 0.1 to 1.5 mm is knitted at a predetermined pitch. Specifically, the pitch of the mesh member 22 is 0.25 to 3 mm, and the width of each opening of the mesh member 22 is larger than the average pore diameter of the micropores of the porous film 20 and is larger than the diameter of the air supply holes 16. Is also small. Specifically, stainless steel, aluminum, various alloys, etc. can be used as the material of the mesh member 22.

  The mesh member 22 has a shape slightly smaller than the inner periphery of the side wall portion 30A of the base portion 30 and is supported from below by a support plate 26.

  The support plate 26 is a plate material having a thickness of 0.5 to 3 mm. The air holes 24 are circular with a diameter of 6 to 50 mm, similar to the air supply holes 16 of the upper surface plate, and are formed in large numbers at a pitch of 8 to 100 mm (pitch between centers). As the material of the support plate 26, stainless steel, aluminum, various alloys, or the like can be used.

  The support plate 26 is provided with a side wall portion 34 projecting downward along the outer periphery thereof, and the side wall portion 34 is fitted inside the side wall portion 30 </ b> A of the base portion 30. Further, the base 30 is provided with an inner peripheral protrusion 30B that protrudes inward from the inner periphery of the side wall 30A, and the side wall 34 of the support plate 26 is supported from below by the inner peripheral protrusion 30B. .

  An introduction hole 30D for introducing air is provided near the center of the bottom plate portion 30C of the base portion 30. An air supply unit 42 such as a blower or a compressor and an air filter 44 are connected to the introduction hole 30D via an air supply pipe 40, and the air from which foreign matter has been removed by the air filter 44 is located above the air supply hole 16 of the top plate 18. Is to be injected.

  Moreover, the thin plate material transport apparatus 10 includes a drive unit 46 for driving the glass substrate 12 in the transport direction.

  The drive unit 46 has a plurality of rollers 48 that contact the lower surface of the glass substrate 12 and drive the glass substrate 12 in the transport direction. These rollers 48 are arranged on both sides in the width direction of the thin plate material conveying air table 14 arranged side by side, and a plurality of pairs of rollers 48 are arranged at an appropriate pitch in the conveying direction. The roller 48 includes a roller portion 48A that contacts the lower surface of the glass substrate 12 and a flange portion 48B that is installed on the outer side in the width direction than the roller portion 48A. The drive unit 46 is installed so that the upper end of the roller portion 48A of the roller 48 is higher than the upper surface of the upper surface plate 18 of the thin plate material conveying air table 14 by several millimeters.

  Next, the operation of the thin plate material conveying apparatus 10 will be described.

  The air table 14 for transporting the thin plate material of the thin plate material transporting apparatus 10 ejects air from the air supply holes 16 of the upper surface plate 18 through the porous film 20, so that it is the same as the air table provided with the porous plate material. Air flow is suppressed from being disturbed, and air is injected from the air supply holes 16 of the top plate 18.

  Further, since the thin porous film 20 has a lower airflow resistance than the porous plate material, the flow rate of the air injected from the air supply holes 16 of the upper surface plate 18 can be increased as compared with the case where the porous plate material is used. . Therefore, a large flying height can be obtained while suppressing air turbulence in the clean room. Furthermore, the porous film 20 is not a source of dust generation.

  In addition, since the porous film 20 is installed below the upper surface plate 18 and in contact with the upper surface plate 18, the portion of the upper surface plate 18 where the air supply holes 16 are not formed is in close contact with the porous film 20, and the porous film 20 is porous. The opening area of the film 20 is reduced accordingly, and the flow rate of air injected from the air supply holes 16 of the upper surface plate 18 is suppressed. However, since the pressure of the air below the porous film 20 can be relatively high, The pressure of the air injected from the air supply holes 16 of the face plate 18 can also be made relatively high, thereby obtaining a large flying height. In other words, the configuration of the thin plate material conveying air table 14 of the first embodiment is suitable for a high pressure type air table that obtains a large flying height by injecting relatively high pressure air onto the thin plate material. .

  The air table 14 according to the first embodiment is configured such that a mesh member 22 is installed under the porous film 20 so as to support the porous film 20 from below, and the thin porous film 20 is formed of the mesh member 22. Since it is reinforced, the durability of the porous film 20 is enhanced.

  Further, in the thin plate material conveying apparatus 10, the plurality of rollers 48 of the drive unit 46 come into contact with the lower surface of the glass substrate 12 to drive the glass substrate 12 in the conveying direction, but the thin plate material conveying air table 14 is not in contact. Since the glass substrate 12 is supported, the force acting on the glass substrate 12 at the contact portion with the roller 48 is small, and surface defects and adhesion of foreign matters due to contact with the roller 48 are suppressed.

  Further, as compared with a transfer device that applies driving force with the pressure of air, it is sufficient to supply only air to support the glass substrate 12, which contributes to a reduction in the manufacturing cost of the device and a small amount of air injection. Therefore, the turbulence of the air in the clean room is suppressed. Furthermore, since complicated control of air is unnecessary, the structure is simple.

  In this way, the thin plate material conveying device 10 supports the glass substrate 12 with a large flying height in a non-contact manner by the thin plate material conveying air table 14, so that the glass substrate 12 and the thin plate material conveying air table 14 Contact can be prevented, and further, air disturbance in the clean room is suppressed, so that the surface of the glass substrate 12 is hardly damaged and foreign matters are not easily attached, and highly reliable conveyance can be realized.

  Further, since a large flying height of the glass substrate 12 can be obtained, when the plurality of thin plate material conveying air tables 14 are installed side by side, the allowable deviation of the height of these upper surface plates 18 is so wide that the installation man-hours are large. Contributes to the reduction of

  The thin plate material conveying air table 14 has a support plate 26 in which a vent hole 24 is formed at a position communicating with the air supply hole 16 of the upper surface plate 18 below the upper surface plate 18. The porous film 20 and the mesh member 22 can be securely fixed and installed with a simple configuration in which the member 22 is sandwiched between the upper surface plate 18 and the support plate 26, and installation work is also easy.

  Next, a second embodiment of the present invention will be described.

  The thin plate material conveying air table 14 of the first embodiment includes a lower position where the mesh member 22 is installed under the porous film 20 so as to support the porous film 20 from below, and the porous film. 20 and the upper position where it is sandwiched between the upper surface plate 18 and the upper position, and can be installed at both positions. In the first embodiment, the porous film 20 is installed in contact with the upper surface plate 18 below the upper surface plate 18, and the mesh member 22 is installed at the lower position so as to support the porous film 20 from below. .

  On the other hand, the second embodiment is characterized in that the mesh member 22 is sandwiched between the porous film 20 and the upper surface plate 18 and installed at the upper position as shown in FIG. Since other configurations are the same as those of the first embodiment, description of the same configurations will be omitted as appropriate.

  As described above, since the mesh member 22 is interposed between the porous film 20 and the upper surface plate 18, the air supply holes 16 in the upper surface plate 18 are formed as schematically shown in FIG. An air passage is formed between the non-existing portion and the porous film 20. Therefore, the substantial opening area of the porous film 20 is larger than that of the first embodiment. Thereby, although the pressure of the air injected from the air supply hole 16 of the upper surface plate 18 is reduced, the flow rate of the air injected from the air supply hole 16 can be further increased as compared with the first embodiment. In the second embodiment, a large flying height is obtained as in the first embodiment. In other words, the configuration of the thin plate material conveying air table 14 of the second embodiment is suitable for a large flow rate type air table that obtains a large flying height by injecting air having a relatively high flow rate into the thin plate material. .

  Further, since the porous film 20 has a lower pressure than the upper side thereof, the porous film 20 is urged to protrude into the air supply holes 16 of the upper surface plate 18, but the mesh member 22 has the porous film 20 and the upper surface plate 18. Therefore, the projecting of the porous film 20 into the air supply hole 16 is suppressed. That is, also in the second embodiment, the thin porous film 20 is reinforced by the mesh member 22, and the durability of the porous film 20 is enhanced.

  In the first and second embodiments, the gas supplied from the thin plate material carrying air table 14 to the lower surface of the glass substrate 12 is air. For example, other gases such as nitrogen gas and rare gas are used as glass. You may supply to the lower surface of the board | substrate 12. FIG.

  In the first and second embodiments, the thin plate material transfer device 10 includes four thin plate material transfer air tables 14 in the width direction. It is good also as a structure provided with the following air tables for thin plate material conveyance, and good also as a structure provided with the air table for 5 or more thin plate material conveyance.

  In the first and second embodiments, the thin plate material conveying apparatus 10 includes the drive unit 46 having the plurality of rollers 48, but may be configured to include a drive unit having a driving belt. Moreover, it is good also as a structure provided with the drive unit in which the roller for driving and the belt were arranged in parallel. Further, the drive unit may be omitted, and the air supply holes of the air table may be inclined and formed on the top plate so as to inject air in the transport direction, and the object to be transported may be driven by the air injected by the air table. .

  Moreover, although the said 1st and 2nd embodiment is for conveying the glass substrate 12, if it is what is called a thin plate-shaped material with a thin plate | board thickness compared with an area, it can also convey other materials. The present invention is applicable. For example, the present invention can be applied to the case of conveying a material that is likely to bend, such as a metal thin plate material or a resin thin plate material.

  The present invention can be used for conveying a thin plate-like material such as a large and thin glass substrate used for a flat panel display such as a liquid crystal display or a plasma display.

The front view including the partial block diagram which shows the thin plate-shaped material conveyance apparatus which concerns on 1st Embodiment of this invention. Sectional drawing which shows the structure of the air table for thin plate material conveyance of the same thin plate material conveyance apparatus Plan view Sectional drawing which expands and shows the structure around the porous film of the air table for conveying the thin plate material Sectional drawing which shows the structure of the air table for sheet-like material conveyance which concerns on 2nd Embodiment of this invention. Sectional drawing which expands and shows the structure around the porous film of the air table for conveying the thin plate material

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Thin plate material conveying apparatus 12 ... Glass substrate (thin plate material)
DESCRIPTION OF SYMBOLS 14 ... Air table for sheet-like material conveyance 16 ... Air supply hole 18 ... Top plate 20 ... Porous film 22 ... Mesh member 24 ... Ventilation hole 26 ... Support plate 28, 30A, 34 ... Side wall part 30 ... Base part 32 ... Fastening member 46 ... Drive unit 48 ... Roller

Claims (5)

  An upper surface plate in which a plurality of air supply holes for supplying gas to the lower surface of the thin plate material is formed, a porous film installed in contact with the upper surface plate under the upper surface plate, and the porous film And a mesh member installed so as to support the sheet from below.   An upper plate having a plurality of air supply holes for supplying gas to the lower surface of the thin plate material, a porous film installed under the upper plate, and sandwiched between the porous film and the upper plate And an air table for conveying a thin plate material. In claim 1 or 2,
A lower position where the mesh member is installed under the porous film so as to support the porous film from below; an upper position where the mesh member is interposed between the porous film and the upper plate; An air table for conveying thin plate materials, which can be installed at both positions. In any one of Claims 1 thru | or 3,
A support plate having a vent hole formed at a position communicating with the air supply hole of the upper surface plate is installed under the upper surface plate, and the porous film and the mesh member are disposed between the upper surface plate and the support plate. An air table for transporting a thin plate material characterized by being sandwiched between two.   A thin plate material transport apparatus comprising the air table for transporting a thin plate material according to any one of claims 1 to 4.

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