JP2008110852A - Floatingly carrying unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a floatingly carrying unit, easy to use, by reducing a facility. <P>SOLUTION: This floatingly carrying unit 10 has a porous plate 76 forming a carrying passage surface F on the upper surface side, an ejector 29 supplying pressurized air, and a pressurized fluid discharge passage 29S supplying the pressurized air exhausted from the ejector 29 to the reverse surface side of the porous plate 76. The porous plate 76 has a suction hole 78 penetrating so as to open in a predetermined position of the carrying passage surface F and sucking the air by negative pressure by a vacuum suction port 29I of the ejector 29. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a floating conveyance unit that floats a workpiece such as a liquid crystal display (LCD), a plasma display panel (PDP), and a color filter and conveys the workpiece in a non-contact manner.

  Glass substrates used in flat panel displays (FPD) such as LCDs and PDPs tend to increase in size in response to demands for larger screens.

  In a conventional FPD manufacturing process, a glass substrate is transported by a roller. However, due to friction between the glass substrate and the roller, a problem of stress applied to the glass substrate, etc., the glass substrate is floated by compressed air and transported. Is considered. For example, the levitation transport unit disclosed in Patent Document 1 requires a negative pressure air supply source for generating suction force in addition to a compressed air supply source for generating positive pressure air.

However, in the levitation conveyance unit disclosed in Patent Document 1, the number of facilities for use increases, and the user can connect a pressurized compressor to the positive pressure supply port and supply negative pressure air to the negative pressure supply port. Since it must be performed separately from the connection of the source, the operation at the time of use is complicated.
JP 2004-331265 A

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a levitation transport unit that can reduce equipment and can be used easily.

  According to the first aspect of the present invention, when a pressurized fluid is supplied, a negative pressure generating means that sucks in from the fluid suction port and discharges the pressurized fluid from the fluid jet port, and is discharged from the fluid jet port. A pressurized fluid discharge path for supplying pressurized fluid to the back side of the transport path surface of the object to be transported, and the transport path surface are formed, and the pressurized fluid supplied from the pressurized fluid discharge path is directed to the transport path surface side. It has a fluid passing body to be passed, and at least one suction hole penetrating the fluid passage body so as to open at a predetermined position on the conveyance path surface and sucked by a negative pressure by the fluid suction port. Yes.

  In the first aspect of the invention, since the negative pressure generating means is provided, the negative pressure generating means is supplied to the negative pressure generating means by supplying only the pressurized fluid without supplying the negative pressure from the outside. It is possible to generate a positive pressure and a negative pressure and supply the positive pressure and the negative pressure to the conveyance path surface side. Therefore, it is possible to reduce the equipment for use, and the user distinguishes between the connection of the pressurized compressor to the positive pressure supply port and the connection of the negative pressure air supply source to the negative pressure supply port. Since it is not necessary, the operation at the time of use is easy.

  In addition, by supplying a pressurized fluid to the negative pressure generating means (for example, an ejector), the pressurized fluid is sucked from the fluid suction port of the negative pressure generating means and discharged from the fluid outlet of the negative pressure generating means. The pressurized fluid discharged from the fluid ejection port is supplied to the back surface side of the transport path surface via the pressurized fluid discharge path, and further from the back surface side of the fluid passing body forming the transport path surface to the transport path surface side. pass. As a result, the pressurized fluid passes through the gap formed in the fluid passage body and is ejected from the conveyance path surface side, and the conveyance path surface of the fluid passage body becomes the air bearing surface. As a result, the workpiece can be lifted and conveyed without causing warpage.

  The suction hole is opened at a predetermined position on the conveyance path surface, and is sucked by a negative pressure by the fluid suction port. Therefore, the floating height of the workpiece can be stabilized by partially sucking the workpiece floating by the fluid ejected from the entire surface of the fluid passing body.

  The invention described in claim 2 is characterized in that a groove for dispersing the pressurized fluid on the back side of the fluid passage is provided on the downstream end side of the pressurized fluid discharge passage.

  As a result, the fluid can be ejected from the entire surface of the fluid passing body, and the entire surface of the fluid passing body can be used as an air bearing surface. Therefore, the flatness of the bearing surface of the fluid passing body is smaller (flatter). can do.

  The invention described in claim 3 is characterized in that a groove for dispersing the pressurized fluid supplied from the pressurized fluid discharge passage is formed on the back surface side of the fluid passage body.

  Thereby, a fluid can be ejected from the whole surface of a fluid passage body with a simple structure, and the whole surface of a fluid passage body can be used as an air bearing surface.

  In the third aspect of the present invention, a groove for dispersing the pressurized fluid on the back surface side of the fluid passing body may be formed on the downstream end side of the pressurized fluid discharge passage. Thereby, it can be set as the groove part of the shape combined with the groove part formed in the downstream end side of a pressurized fluid discharge channel, and the groove part formed in the back surface side of the fluid passage body, and the variation of groove shape spreads .

  The invention described in claim 4 is characterized in that the back surface of the fluid passage body is formed as a flattened surface.

  Thereby, the flatness degree of the conveyance path surface of a fluid passage body can be made small (more flat).

  According to a fifth aspect of the present invention, the back side of the fluid passage body is an airtight space, and the airtight space is divided into at least one suction chamber communicating with the suction hole and the fluid suction port, and the suction chamber. And at least one ejection chamber communicating with the pressurized fluid discharge path.

  Accordingly, the fluid can be reliably ejected from the fluid passage body, and the fluid can be sucked from the suction port.

  The invention described in claim 6 is characterized in that a plurality of the suction holes are formed, and at least one of the suction chambers communicates with the plurality of suction holes.

  As a result, the flying height of the workpiece can be further stabilized, and it is possible to reliably avoid adverse effects such as warping of the workpiece due to suction from the suction holes.

The invention according to claim 7 is that a plurality of the suction holes are formed, and the same number of the negative pressure generating means as the suction holes are provided so that the suction holes are respectively connected to the fluid suction ports. Features.
Thereby, the suction amount from each suction hole can be controlled individually and reliably.

The invention according to claim 8 is characterized in that a plurality of the suction chambers are formed, and the same number of the negative pressure generating means connected to the suction chambers as the suction chambers are provided.
Thereby, the suction of the pressurized fluid from the suction chamber can be performed more rapidly and efficiently.

  Since this invention was set as the said structure, it can use easily, reducing an installation.

  Hereinafter, embodiments will be described and embodiments of the present invention will be described. In the second and subsequent embodiments, the same components as those already described are denoted by the same reference numerals, and description thereof is omitted.

[First Embodiment]
First, the first embodiment will be described. 1 to 3 show an exposure apparatus 12 in which a floating conveyance unit 10 according to this embodiment is incorporated. In the present embodiment, the exposure apparatus will be described as an example. However, the present invention can also be applied to an inspection apparatus and the like, and the scope of application of the present invention is not limited to the exposure apparatus.

  The exposure apparatus 12 includes an assembly frame 18 configured in a long frame shape with rails 14 and cross members 16. The assembly frame 18 is supported above the frame-like base frame 22 by the post 20. A caster 24 and a stopper 26 are attached to the base frame 22 so that the exposure apparatus 12 can be moved and installed in the work area.

  A plurality of beam members 28 are bridged between the rails 14. On the beam member 28, the floating conveyance units 10 according to the present embodiment are incorporated in three rows. Since the configuration of each column is the same, the configuration of one of these three columns will be described below, and the description of the other columns will be omitted.

  The levitation conveyance unit 10 is provided on a chamber 36 having an airtight space, an ejector 29 for supplying a negative pressure fluid and a positive pressure fluid to the airtight space of the chamber 36, and an upper side of the chamber 36, and conveys a workpiece (glass substrate P). And a porous plate 76 made of a fluid passage body with a road surface F formed on the upper surface side.

  On the beam member 28 on one end side of the chamber 36, the above-described ejector 29 to which pressurized air is supplied from the first compressor 32 via the tube 34 is disposed. The ejector 29 is configured to generate a negative pressure and a positive pressure with the pressurized air supplied from the first compressor 32. Note that what is supplied from the compressor is not limited to air, but may be an inert gas such as nitrogen, argon, or helium, or a gas such as carbon dioxide. Moreover, liquids, such as water, may be sufficient.

  Further, a height adjusting member 30 for adjusting the height of the chamber 36 is disposed on the beam member 28 on which the ejector 29 is not disposed.

  The bottom plate of the chamber 36 has one negative pressure supply port 56M (see FIG. 8) connected to the ejector 29 and sucked in air, and two positive pressure supply ports connected to the ejector 29 and supplied with pressurized air. 60M1 and 60M2 (see FIG. 8) are formed.

  Further, a support plate 38 is bridged between the rails 14 on the right side of the rails 14 shown in FIG. Note that a levitation conveyance unit 40 according to a second embodiment to be described later is set on the support plate 38.

  Further, a linear transport device 50 is mounted on the rail 14 on the near side. The transport device 50 includes a plurality of vacuum suction cups 52, and chucks the lower surface of the floated glass substrate P and transports it in the direction of the arrow.

  The glass substrate P levitated above the levitation conveyance unit 10 is levitated and conveyed by the conveyance device 50. The glass substrate P that has been levitated and conveyed is exposed by an exposure means (not shown) while the levitated state is maintained above the levitating and conveying unit 40 to form a predetermined circuit pattern.

  Next, a specific configuration of the levitation transport unit 10 according to the first embodiment will be described.

  As shown in FIG. 8, the ejector 29 constituting the levitation transport unit 10 includes a base body 29B on which a chamber 36 is placed. A tube 34 shown in FIG. 1 is connected to the inside of the base body 29B, and a pressurized fluid supply port 29C to which pressurized air (compressed air) is supplied, and air that flows in from the pressurized fluid supply port 29C are ejected. A nozzle portion 29N and a diffuser 29D disposed on the downstream side of the nozzle portion 29N are provided.

  A pressurized fluid discharge passage 29S is connected to the downstream end side of the diffuser 29D. The pressurized fluid discharge passage 29S is branched into two, and the two downstream ends 29E1 and 29E2 are connected to the two positive pressure supply ports 60M1 and 60M2 of the chamber 36, respectively.

  Further, the ejector 29 is provided with a vacuum suction port 29I connected to the negative pressure supply port 56M of the chamber 36. The nozzle portion 29N, the diffuser 29D, and the vacuum suction port 29I communicate with the diffusion chamber 29Z that constitutes the ejector 29.

  As shown in FIGS. 4 to 9, the chamber 36 constituting the levitation conveyance unit 10 is a long cylindrical body having a rectangular cross section, and the inner space is substantially the center of the two partition walls 54 provided inside. The suction chamber 56 has a triangular cross section, and the ejection chambers 58 and 60 have a trapezoidal cross section. And as shown in FIG. 8, the side plate 62 is joined to the end surface of the chamber 36, whereby the suction chamber 56 and the ejection chambers 58, 60 of the chamber 36 become an airtight space. A negative pressure supply port 56M is formed on the bottom wall of the suction chamber 56, and positive pressure supply ports 60M1 and 60M2 are formed on the bottom walls of the ejection chambers 58 and 60, respectively.

  As shown in FIG. 6, a pedestal portion 152 in which a screw hole 150 is formed is provided on the end surface of the chamber 36. Further, a mounting hole 154 is formed in the side plate 62. The screw hole 150 and the attachment hole 154 are formed in a positional relationship where the screw hole 150 and the attachment hole 154 face each other when the side plate 62 is overlapped on the end face of the chamber 36. Then, the screw 36 is inserted into the mounting hole 154 and the screw hole 150 with the screw hole 150 and the mounting hole 154 facing each other, whereby the chamber 36 and the side plate 62 are screwed together.

  The chamber 36 and the side plate 62 can be joined by other means such as an adhesive in addition to screwing with the screw 156.

  However, when the chamber 36 and the side plate 62 are bonded together with an adhesive, the curing time of the adhesive is required, so that the manufacturing efficiency cannot be improved, and it is difficult to disassemble after the bonding. Therefore, it is difficult to perform maintenance or replacement of parts. Therefore, it is preferable to join the chamber 36 and the side plate 62 with the screw 156 as described above.

  A long groove 64 is formed on the side surface of the chamber 36 along the longitudinal direction in order to reduce the weight.

  On the other hand, the ceiling wall of the chamber 36 is divided into four sections, and concentric circle groove portions 66 and lattice-like lattice groove portions 68 are formed on both sides of the circle groove portions 66, respectively. The reason why the circle groove portions 66 and the lattice groove portions 68 are formed separately is that air can be uniformly supplied to the porous plate 76 joined to the ceiling wall. However, in the present invention, the number of sections in which the circle groove section 66 and the lattice groove section 68 are formed is not limited, and the chamber 36 may be configured by one section.

  A plurality of ventilation holes 74 pass through the groove bottom of the lattice groove 68 and are arranged in a straight line. The vent hole 74 communicates with the ejection chamber 58. An intake hole 70 is formed at the center of the circle groove 66 and communicates with the suction chamber 56. Further, on the concentric circle of the intake hole 70, a vent hole 72 is formed at the groove bottom side by side in the radial direction. The vent hole 72 communicates with the ejection chamber 60.

  A porous plate 76 processed into a plate shape is joined to the ceiling wall of the chamber 36 in which the groove portion is formed in this way. For example, porous carbon, sintered metal, porous ceramics, porous resin, and the like can be used for the porous plate 76. However, when porous carbon is used, improvement in weight reduction, improvement in mechanical strength, The manufacturing cost can be reduced, the flatness of the surface can be improved, and damage to the glass substrate P can be reduced when it comes into contact with the glass substrate P.

  In a state where the chamber 36 and the porous plate 76 are joined, the suction hole 70 formed in the chamber 36 and the suction hole 78 formed in the porous plate 76 communicate with each other so as to face each other.

  As a joining method, the porous plate 76 is placed on the surface plate with the surface to be the air bearing surface of the porous plate 76 facing down, and an adhesive is applied to the ceiling wall of the chamber 36 to overlap the porous plate 76. An example is a method of placing and fixing a weight. The adhesive is preferably applied so as not to protrude into the circle groove portion 66 and the lattice groove portion 68.

  Here, the circle groove portion 66 and the lattice groove portion 68 are not formed on the back surface of the porous plate 76 but formed on the ceiling wall of the chamber 36 in comparison with the case where the groove portion is formed on the back surface of the porous plate 76. This is because the groove portion can be easily formed with high accuracy when the groove portion is formed in the ceiling portion of the chamber.

  In particular, in order to reduce the variation in the flying height of the glass substrate P and stably float it, the flatness of the bearing surface of the porous plate 76 needs to be made small (more flat). If a groove is formed on the back surface of the plate, it becomes difficult to reduce the flatness of the bearing surface of the porous plate 76.

  On the other hand, in this embodiment, since the groove portion is not formed on the back surface of the porous plate 76, the flatness of the bearing surface of the porous plate 76 can be reduced. The flying height can be stably floated with less variation.

  Of course, it is possible to form a groove on the back side of the porous plate 76. In this case, it is possible to have a structure in which a groove is formed on the ceiling wall of the chamber 36 and the groove shape is determined by both the groove formed on the back surface side of the porous plate 76.

  Here, a mechanism in which air is ejected from the gap of the porous plate 76 to make the entire surface an air bearing surface will be briefly described.

  In the porous plate 76, a plurality of fine voids communicating with each other are formed. The air ejected from the circle groove portion 66 and the lattice groove portion 68 passes through the air gap formed by the circle groove portion 66, the lattice groove portion 68, and the lower surface of the porous plate 76, passes through the void of the porous plate 76, and is porous. It ejects from the bearing surface of the material plate 76 toward the outside. At this time, since the minute gaps communicate with each other, the fine gaps are ejected not only from above the air passage but also from the entire bearing surface.

  Next, functions and effects of the levitation transport unit 10 according to the first embodiment will be described.

  Pressurized air is supplied from the first compressor 32 to the pressurized fluid supply port 29 </ b> C of the ejector 29. Then, the pressurized air is squeezed by the nozzle portion 29N and discharged to the diffusion chamber 29Z at a high speed.

  The pressurized air discharged into the diffusion chamber 29Z flows into the pressurized fluid discharge passage 29S while expanding and diffusing, and at this time, the pressure in the diffusion chamber 29Z is reduced by Bernoulli's theorem.

  When the pressure in the diffusion chamber 29Z decreases, the pressure in the negative pressure fluid inflow passage 29L communicating with the diffusion chamber 29Z also decreases. Therefore, the air in the suction chamber 56 formed in the chamber 36 is also sucked through the vacuum suction port 29I communicating with the negative pressure fluid inflow passage 29L, and the pressure in the suction chamber 56 is reduced.

  On the other hand, the pressurized air released into the diffusion chamber 29Z passes through the diffuser 29D and the pressurized fluid discharge passage 29S together with the sucked air in the suction chamber 56 and flows to the downstream ends 29E1, 29E2, and this downstream end It is supplied to the ejection chambers 58 and 60 through positive pressure supply ports 60M1 and 60M2 connected to 29E1 and 29E2.

  Therefore, in the present embodiment, by providing the ejector 29, only the pressurized air is supplied from the first compressor 32 without supplying negative pressure to the ejector 29 from the outside, so that positive pressure and negative pressure are supplied to the ejector 29. This positive pressure and negative pressure can be generated on the side of the conveyance road surface F.

  The air supplied to the ejection chambers 58, 60 is ejected from the vent holes 72, 74, travels through the air passage formed by the lower surface of the porous plate 76 and the circle grooves 66 or the lattice grooves 68, and the porous plate 76. It spreads evenly on the lower surface of the porous plate 76 and is ejected from the gap of the porous plate 76.

  That is, since air is ejected from the entire surface of the porous plate 76 and the entire surface of the porous plate 76 becomes an air bearing surface, the glass substrate P is levitated without generating warpage and is not in contact with the porous plate 76. It becomes possible to convey with. The sucker 52 chucks the floated glass substrate P, and the transport device 50 transports it in the direction of the arrow.

  Further, the negative pressure supplied to the suction chamber 56 generates a force for sucking the glass substrate P through the suction holes 78 formed in the porous plate 76 through the suction holes 70. The suction force generated by the intake holes 70 regulates the flying height of the glass substrate P that has been floated by the air ejected from the porous plate 76. Therefore, the flying height of the glass substrate P can be controlled by controlling the suction force.

  In the upper periphery of the intake hole 70, the glass substrate P that has been levitated by the suction force generated by the intake hole 70 is bent downward (in the direction of the porous plate 76).

  However, a concentric circle groove portion 66 is formed around the intake hole 70, and positive pressure air is ejected from the circle groove portion 66 to the porous plate 76. Therefore, the downward deflection generated in the glass substrate P is not caused. It is pressed upward (in the direction opposite to the porous plate 76).

  Accordingly, the glass substrate P can be transported in a flat state. In particular, when the size of the glass substrate P is increased, it becomes difficult to transport the glass substrate P flat without bending. However, according to the present invention, even the enlarged glass substrate P is bent. It is possible to convey without any problems.

  In particular, in the present embodiment, a plurality of the suction holes 70 and the suction holes 78 are formed, and the suction chamber 56 communicates with the plurality of suction holes 70 and the suction holes 78. It has become prominent.

  The pressure P1 of the air ejected from the vent hole 72 is preferably larger than the pressure P2 of the air ejected from the vent hole 74 (P1> P2), and P1 is twice as large as P2 (P1 = 2P2). preferable.

  If the relationship between P1 and P2 is configured in this way, it is possible to effectively suppress the occurrence of bending of the glass substrate P and to stably float the glass substrate P.

  In addition, since the suction hole 70 and the suction hole 78 are located at the center of the circular jet air that floats the glass substrate P, it is easy to balance the flying force and the suction force, and the flying height of the glass substrate P. Can be easily regulated.

[Second Embodiment]
Next, a second embodiment will be described. In the following description, portions related to the second embodiment will be described, and description of the same matters as those of the floating conveyance unit 10 will be omitted.

  As shown in FIGS. 1 to 3, the levitation transport unit 40 according to the second embodiment includes an ejector 29 attached to the lower surface side of the support plate 38, a chamber 80 provided on the upper surface side of the support plate 38, And a porous plate 82 made of a fluid passage body provided on the upper side of 80.

  In the ejector 29, negative pressure and positive pressure are generated by the pressurized air supplied from the second compressor 44 via the tube 46. Then, negative pressure and positive pressure air are respectively supplied from the ejector 29 to a negative pressure supply port and a positive pressure supply port (both not shown) formed in the bottom plate of the chamber 80 of the levitation conveyance unit 40.

  Further, as shown in FIGS. 10 and 11, the ceiling wall of the chamber 80 is formed with four longitudinal groove portions 97 in the longitudinal direction and a plurality of transverse groove portions 102 in the width direction. In 102, a plurality of remote islands 86 are formed at predetermined intervals. A vent hole 92 is formed in the groove bottom of the lateral groove portion 102. The vent hole 92 communicates with an ejection chamber (not shown). The remote island 86 has an intake hole 90 communicating with the suction chamber.

  On the other hand, a suction hole 96 is formed on the surface of the porous plate 82 at a position corresponding to the suction hole 90 when it is overlapped with the ceiling wall of the chamber 80. Further, through holes 101 are formed on both sides of the porous plate 82, and the porous plate 82 can be fixed to the chamber 80 by inserting screws into the mounting holes 94 formed in the chamber 80. Yes.

  As described above, in the present embodiment, by providing the ejector 29, similarly to the levitation conveyance unit 10 of the first embodiment, only the pressurized air is supplied to the ejector 29 without supplying negative pressure from the outside. By supplying from the compressor 44, a positive pressure and a negative pressure can be generated in the ejector 29, and the positive pressure and the negative pressure can be generated on the conveyance path surface F side. Therefore, even if negative pressure air is not supplied, the glass substrate P can be transported satisfactorily without causing adverse effects such as warping.

  Further, by forming the through hole 101 on the surface of the porous plate 82, screws can be fixed. Further, since the groove is not formed in the porous plate 82, the flatness of the porous plate 82 can be maintained. Furthermore, by arranging the intake holes at equal intervals, the flying height of the glass substrate P can be regulated in a well-balanced manner.

  In the embodiment shown in FIGS. 1 to 9, the levitation transport unit 10 is configured by joining four porous plates 76 to the ceiling wall of the chamber 36. In the embodiment shown in FIGS. 10 and 11, the levitation conveyance unit 40 has a single porous plate 82 bonded to the ceiling wall of the chamber 80. However, in the present invention, the number of porous plates is not limited.

[Third Embodiment]
Next, a third embodiment will be described. FIG. 12 is a side cross-sectional view showing a cross-sectional shape in a vertical cross section passing through the suction hole 78 along the short direction of the levitation transport unit 110 according to the present embodiment.

  As shown in FIG. 12, in the levitation transport unit 110 according to the present embodiment, the same number of ejectors 29 as the suction holes 78 (that is, the same number as the suction holes 70) are provided, and the vacuum suction ports 29I of the respective ejectors 29 are provided with the respective suction Each is connected to a hole 78.

  As a result, the suction flow rate from each intake hole can be controlled individually and reliably.

[Fourth Embodiment]
Next, a fourth embodiment will be described. 13 to 15 show the levitation transport unit 130 according to the present embodiment. As shown in FIGS. 13 to 15, in the levitation transport unit 130 according to the present embodiment, the chamber 136, the ejector 129 incorporated in the transport direction upstream end portion or the transport direction downstream end portion of the chamber 136, and the fluid passage And a porous plate 176 made of a body.

  As shown in FIG. 13 (A), the chamber 136 is placed on the beam 28, and as shown in FIGS. 13 (A) and 13 (C), the chamber 136 has a removable engaging portion such as a snap lock 140 or the like. Is detachably fixed to the beam member 28. Further, suction chambers 158 and 160 are formed in both sides along the transport direction in the chamber 136, and an ejection chamber 157 is formed between the suction chamber 158 and the suction chamber 160. A leg 138 (see FIGS. 13C and 15D) is formed at the bottom of the chamber 136, and the leg 138 is in contact with the beam member 28.

  As shown in FIG. 14, the ejector 129 includes a base body 129B. Inside the base body 129B, an ejector heart portion 128 having the same components as the diffusion chamber 29Z, the diffuser 29D, and the nozzle portion 29N described in the first embodiment is provided. Further, a pressurized fluid supply port 129C to which pressurized air is supplied is formed on the lower surface side of the base body 129B, and the pressurized air supplied from the pressurized fluid supply port 129C is sent to the ejector heart portion 128. It is like that.

  Furthermore, as shown in FIG. 14, a pressurized fluid discharge path 129S connected to the downstream end side of the diffuser is formed in the base body 129B. A pressurized fluid discharge port 157E, which is a downstream end of the pressurized fluid discharge path 129S, communicates with the ejection chamber 157 of the chamber 136.

  The base 129B is formed with vacuum suction paths 129J1 and 129J2 that are connected to the ejector heart portion 128 and branch into two. The vacuum suction ports 129I1 and 129I2 that are the downstream ends of the vacuum suction paths 129J1 and 129J2 communicate with the suction chambers 158 and 160, respectively.

  As shown in FIG. 15, the longitudinal groove portion 197, the lateral groove portion 202, and the remote island 186 are formed in the chamber 136, similarly to the chamber 36. In addition, the chamber 136 communicates with the ejection chamber 157 and communicates with the vent hole of the porous plate 176, and communicates with the suction chamber 158 or the suction chamber 160 and communicates with the suction hole of the porous plate 176. An intake hole 190 is formed.

  In the present embodiment, by providing the ejector 129, positive pressure and negative pressure are generated in the ejector 129 by supplying only pressurized air from the first compressor 32 without supplying negative pressure to the ejector 129 from the outside. Thus, the positive pressure and the negative pressure can be generated on the side of the conveyance path surface F.

  The air supplied to the ejection chamber 157 is ejected from the gap of the porous plate 176. That is, air is ejected from the entire surface of the porous plate 176, and the entire surface of the porous plate 176 becomes an air bearing surface. Therefore, the glass substrate P is levitated without causing warpage and is not in contact with the porous plate 176. It becomes possible to convey with. The sucker 52 (see FIG. 1) chucks the floated glass substrate P, and the conveying device 50 (see FIGS. 1 and 2) conveys it in the direction of the arrow.

  In the present embodiment, a suction hole is formed in the porous plate 176 to generate a force for sucking the glass substrate P (work). This suction force regulates the flying height of the glass substrate P that has been levitated by the air ejected from the porous plate 176. Therefore, the flying height of the glass substrate P can be controlled by controlling the suction force.

  Therefore, similarly to the first embodiment, the glass substrate P can be transported in a flat state.

  In this embodiment, the chamber 136 is easily attached and detached by providing an engaging portion such as the snap lock 140, but an engaging portion such as the snap lock 140 may be provided in the first to third embodiments.

[Fifth Embodiment]
Next, a fifth embodiment will be described. As shown in FIG. 16, in the present embodiment, an ejector 229 in which two ejector heart portions are arranged is provided in place of the ejector 129 as compared with the fourth embodiment.

  In the ejector 229, the ejector heart 228A is disposed near the vacuum suction port 129I1, and the ejector heart 228B is disposed near the vacuum suction port 129I2. The configuration of the ejector heart 228A, 228B is the same as that of the ejector heart 128.

  Further, the ejector 229 is provided with connecting pipes 230A and 230B branched from the pressurized fluid discharge path 129S in the chamber width direction and connected to the ejector heart portions 228A and 228B, respectively.

  Further, the ejector 229 is provided with a flow rate adjusting means 232A connected to the ejector heart portion 228A and extending downward, and a flow rate adjusting means 232B connected to the ejector heart portion 228B and extending downward. The flow rate adjusting means 232A and 232B are pipe-shaped and are provided to adjust the flow rate of the pressurized fluid and adjust the degree of vacuum.

  The ejector 229 is connected to the ejector heart 228A and opens to the chamber side wall (lateral wall) to discharge the pressurized fluid (air). The ejector 229 is connected to the ejector heart 228B and opens to the chamber side wall. And a discharge path 234B for discharging the pressurized fluid.

  According to the present embodiment, the ejection of the pressurized fluid (air) to the ejection chamber 157 and the suction of the pressurized fluid from the suction chambers 158 and 160 can be performed more rapidly and efficiently than the fourth embodiment. .

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention.

  For example, in the embodiment shown in FIG. 1 to FIG. 15, the levitation transport unit of the present invention is incorporated in the exposure apparatus, but the present invention is not limited to this. It can be used for the apparatus for conveying.

  Furthermore, in embodiment shown in FIGS. 1-15, although the glass substrate was demonstrated to the example as a to-be-conveyed body conveyed by the levitation conveyance unit which concerns on this invention, this invention is not limited to this, For example, a member to be transported other than a glass substrate such as a resin plate or a metal plate may be transported.

It is a perspective view which shows the exposure apparatus with which the levitation conveyance unit which concerns on 1st Embodiment, and the levitation conveyance unit which concerns on 2nd Embodiment were assembled | attached. It is a side view which shows the exposure apparatus with which the levitation conveyance unit which concerns on 1st Embodiment, and the levitation conveyance unit which concerns on 2nd Embodiment were assembled | attached. It is a top view which shows the exposure apparatus with which the levitation conveyance unit which concerns on 1st Embodiment, and the levitation conveyance unit which concerns on 2nd Embodiment were assembled | attached. It is a perspective view of the levitation conveyance unit concerning a 1st embodiment. It is a disassembled perspective view of the levitation conveyance unit concerning a 1st embodiment. It is a perspective view which shows the attachment structure of the side plate of the levitation conveyance unit which concerns on 1st Embodiment. It is an enlarged plan view of the levitation transport unit according to the first embodiment. It is a sectional side view which shows the structure of the ejector and chamber of the levitation conveyance unit which concern on 1st Embodiment. It is a sectional side view of the levitation conveyance unit concerning a 1st embodiment. It is a top view of the chamber of the levitation conveyance unit concerning a 2nd embodiment. It is a top view of the porous board of the levitation conveyance unit concerning a 2nd embodiment. It is a sectional side view which shows the structure of the ejector and chamber of a levitation conveyance unit which concern on 3rd Embodiment. FIGS. 13A to 13C are a partial perspective view of a chamber, a perspective view of an ejector, and a cross-sectional view of the chamber taken along the arrow 13C-13C, respectively, constituting the levitation transport unit according to the fourth embodiment. It is. FIGS. 14A and 14B are a partial plan sectional view (a sectional view taken along arrows 14A-14A in FIG. 14B) and a partial side sectional view, respectively, of the levitation transport unit according to the fourth embodiment. It is sectional drawing (arrow 14B-14B of FIG. 14 (A)). FIGS. 15A to 15D are a plan view, a side view, a rear view, and an arrow view 15D-15D of FIG. 15B, respectively, of the chamber constituting the levitation transport unit according to the fourth embodiment. It is sectional drawing. FIGS. 16A and 16B are a partial plan view and a front view, respectively, of a levitation transport unit according to the fifth embodiment.

Explanation of symbols

10 Levitation transport unit 29 Ejector (negative pressure generating means)
29I Vacuum suction port (fluid suction port)
29S Pressurized fluid discharge passage 29D Diffuser (fluid outlet)
40 Levitation transport unit 42 Ejector (negative pressure generating means)
56 Suction chamber 58 Ejection chamber 60 Ejection chamber 66 Circle groove (groove)
76 Porous plate (fluid passing body)
78 Suction hole 82 Porous plate (fluid passing body)
96 Suction hole 110 Levitation conveyance unit 120 Levitation conveyance unit 129 Ejector (negative pressure generating means)
129S Pressurized fluid discharge path 129I1 Vacuum suction port (fluid suction port)
129I2 Vacuum suction port (fluid suction port)
130 Levitation conveyance unit 157 Ejection chamber 158 Suction chamber 160 Suction chamber 176 Porous plate (fluid passing body)
229 Ejector F Transport road surface

Claims (8)

A negative pressure generating means for sucking from the fluid suction port and discharging the pressurized fluid from the fluid ejection port by being supplied with the pressurized fluid;
A pressurized fluid discharge path for supplying the pressurized fluid discharged from the fluid ejection port to the back side of the transfer path surface of the object to be transferred;
A fluid passing body that forms the transport path surface and allows the pressurized fluid supplied from the pressurized fluid discharge path to pass to the transport path surface side;
At least one suction hole that penetrates the fluid passing body so as to open at a predetermined position on the conveyance path surface, and is sucked by negative pressure by the fluid suction port;
A levitating conveyance unit characterized by comprising:   The levitation conveyance unit according to claim 1, wherein a groove portion that disperses the pressurized fluid on the back surface side of the fluid passage body is provided on the downstream end side of the pressurized fluid discharge path.   The levitation conveyance unit according to claim 1 or 2, wherein a groove for dispersing the pressurized fluid supplied from the pressurized fluid discharge passage is formed on a back surface side of the fluid passage body.   The levitation conveyance unit according to any one of claims 1 to 3, wherein a back surface of the fluid passage body is formed as a flattened surface. The back side of the fluid passing body is an airtight space,
The airtight space includes at least one suction chamber communicating with the suction hole and the fluid suction port;
The suction chamber is partitioned and at least one ejection chamber communicating with the pressurized fluid discharge path;
The levitation conveyance unit according to any one of claims 1 to 4, wherein the levitation conveyance unit is configured as follows. A plurality of the suction holes are formed,
The levitation conveyance unit according to claim 5, wherein the suction chamber communicates with the plurality of suction holes. A plurality of the suction holes are formed,
The levitation conveyance unit according to claim 5 or 6, wherein the same number of the negative pressure generating means as the suction holes are provided so that the suction holes are connected to the fluid suction ports, respectively. A plurality of the suction chambers are formed,
The levitation conveyance unit according to claim 5 or 6, wherein the number of the negative pressure generating means connected to each of the suction chambers is the same as that of the suction chambers.

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