JP2007176637A - Non-contact conveying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-contact conveying device achieving enhancement of energy efficiency and energy-saving by effectively utilizing energy possessed by a fluid. <P>SOLUTION: The non-contact conveying device 1 for retaining/conveying a plate-like body in a non-contact manner is provided with an approximately cylindrical body 2 formed with a recessed part cylinder chamber 3 having a circumferential inner peripheral surface 7; a flat end surface 4 formed on an opening side of the recessed part cylinder chamber 3 of the body 2; a nozzle 5 formed so as to be faced to the inner peripheral surface 7 of the recessed part cylinder chamber 3 and delivering the fed fluid into the recessed part cylinder chamber 3; and a fluid passage connected with the nozzle 5 and feeding the fluid into the recessed part cylinder chamber 3 through the nozzle 5. The nozzle 5 is arranged at a position separated to an inner side more than the inner peripheral surface 7 of the recessed part cylinder chamber. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a non-contact conveying device used for holding, conveying, rotating, etc. a plate-like body in a non-contact manner.

Conventionally, when a workpiece such as a semiconductor wafer or a glass substrate is transported or transferred, or at the process stage, the workpiece is held by vacuum suction such as an end effector or a vacuum stage, mechanical chucking, or the like. In these methods, since the workpiece and the vacuum suction part or chucking part are in direct contact with each other, problems such as particle transfer from the contact part to the workpiece, metal contamination, scratches due to contact, and generation of static electricity due to peeling due to vacuum breakage may occur. is there.
In order to solve such problems, a non-contact conveying apparatus using compressed air and utilizing Bernoulli's theorem is now being put into practical use. According to this non-contact conveyance device, it is possible to hold a workpiece in a non-contact manner, but generally there is a problem that the holding force is weak. In the non-contact conveyance device disclosed in Patent Document 1, although the force for sucking and holding the plate-like body by rotating the fluid is improved, from the viewpoint of hydrodynamics, in terms of energy efficiency and consumption flow rate There is room for improvement.
JP-A-2005-51260

As described above, in the conventional non-contact conveyance device, cost and ease of handling are emphasized, and energy efficiency is rarely considered. However, in view of the fact that the consumption flow rate is increasing in order to transport and hold large-diameter, thinned semiconductor wafers and large-sized glass substrates, the energy efficiency and energy savings of the devices in this technical field are increased. Has become a major issue.
In April 1999, the conventional energy conservation law was significantly strengthened, and the “Revised Energy Conservation Law” was enacted. In addition, the introduction of a “domestic emissions trading system” in which domestic businesses trade greenhouse gas emissions is being considered as an additional measure. In addition, energy saving is a global issue in view of the fact that the world-wide warming gas emissions trading is progressing.
The present invention has been made in view of the above-described circumstances, and pays attention to microscopic energy loss that has not been noticed in the conventional non-contact conveyance device, and effectively uses the energy of the fluid to achieve energy efficiency. It aims to improve and save energy.

  In order to solve the above-described problems, the present invention provides a substantially columnar main body having a concave cylindrical chamber whose inner peripheral surface is a circular shape, and a flat shape formed on the concave cylindrical chamber opening side of the main body. An end surface and a nozzle that is formed so as to face the inner peripheral surface of the concave cylindrical chamber and that discharges supply fluid into the concave cylindrical chamber, communicates with the nozzle, and allows fluid to flow into the concave cylindrical chamber through the nozzle. A non-contact transfer device, wherein the nozzle is disposed at a position farther inward than the inner circumferential surface of the concave cylindrical chamber.

  In the above configuration, two nozzles may be arranged at positions that are point-symmetric with respect to the center of the circumference of the concave cylindrical chamber.

  Moreover, said structure WHEREIN: The said nozzle may be arrange | positioned in the middle of the said recessed cylindrical chamber.

  In the above configuration, the nozzle is provided to have a predetermined angle θ with respect to a tangent that is in contact with the inner circumference at the discharge point P, and the angle θ extends from the discharge point P in the fluid discharge direction. When the radius r1 perpendicular to the line L1 is drawn, the distance δ between the intersection point P2 of the radius r1 and the line L1 and the intersection point P3 of the radius r1 and the circumference of the concave cylindrical chamber is δ / r1 = 5% − It may be set to satisfy 25%.

  In the above configuration, the opening edge of the concave cylindrical chamber may be curved smoothly from the inner peripheral surface of the concave cylindrical chamber and extend to the outer edge of the concave cylindrical chamber opening.

<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view illustrating a configuration of a non-contact conveyance device 1 according to the present embodiment. (A) is the figure seen from diagonally downward, (b) is the figure seen from diagonally upward. FIG. 2 is a cross-sectional view of the non-contact conveyance device 1. (A) is the II sectional view taken on the line of Fig.1 (a), (b) is the II-II sectional view taken on the line of Fig.1 (a).
As shown in these drawings, the non-contact conveyance device 1 has a substantially columnar swirl flow forming body 2. A concave cylindrical chamber 3 is formed in the swirl flow forming body 2 so as to form a columnar space and its lower end is an opening. The opening side of the concave cylindrical chamber 3 is a flat facing surface 4 that is opposed to a plate-like body (a plate-like workpiece such as a wafer) and whose facing surface is formed flat.
The opening edge 7 forming the periphery of the opening of the concave cylindrical chamber 3 has a curved shape with a smooth cross section. That is, the cross-sectional shape of the opening edge 7 is a shape that smoothly curves from the inner peripheral surface of the concave cylindrical chamber 3 and extends to the outer edge of the opening as shown in FIG. In this case, the curvature of the opening edge 7 is, for example, about R2.5, and its surface is preferably extremely smooth.

Next, reference numeral 5 in FIGS. 1 and 2 denotes a short offset nozzle that discharges fluid into the concave cylindrical chamber 3 and is formed so as to face the concave cylindrical chamber 3. The short offset nozzle 5 communicates with a bell mouth fluid passage 6 for supplying fluid into the concave cylindrical chamber 3 through the nozzle.
As shown in FIG. 2A, the short offset nozzle 5 is provided so as to have a predetermined angle θ with respect to a tangent line that is in contact with the inner periphery at the discharge point P. When the radius r1 perpendicular to the line L1 extending in the fluid discharge direction is subtracted from the discharge point P, the angle θ is between the intersection point P2 of the radius r1 and the line L1, and the intersection point P3 of the radius r1 and the circumference. The distance (hereinafter referred to as offset) δ is set to satisfy δ / r1 = 5% to 25%.
By providing the offset δ in this way, the shear resistance force on the wall surface of the concave cylindrical chamber 3 when the fluid is discharged from the short offset nozzle 5 into the concave cylindrical chamber 3 can be suppressed, and the entrainment effect can be increased. Therefore, the input energy can be more efficiently converted into rotational momentum.

  Moreover, the short offset nozzle 5 is arrange | positioned so that the up-down direction middle of the recessed cylinder chamber 3 may be faced, as FIG.2 (b) shows. The position of the short offset nozzle 5 in this case may be set such that the distance h1 from the upper surface of the concave cylindrical chamber 3 with respect to the height h of the concave cylindrical chamber 3 satisfies h1 / h = 35% to 75%. preferable. When the short offset nozzle 5 is disposed above the concave cylindrical chamber 3, the fluid discharged into the concave cylindrical chamber 3 causes friction with the upper surface of the concave cylindrical chamber 3 due to its viscosity, and the boundary layer develops. However, when the nozzle position is arranged in the middle of the concave cylindrical chamber 3, friction with the upper surface of the concave cylindrical chamber 3 can be suppressed, and as a result, it can be efficiently converted into a rotational force and energy. Loss can be suppressed.

In the case of this embodiment, two short offset nozzles 5 are arranged at positions that are point-symmetric with respect to the center 0 of the circumference, as shown in FIG. The fluid discharged from the short-offset nozzle 5 facing the point symmetry into the concave cylindrical chamber 3 swirls along the inner wall of the concave cylindrical chamber 3 and gradually decelerates. And centrifugal force increases. FIG. 4A is a diagram showing a pressure distribution when two short offset nozzles 5 are arranged point-symmetrically, and FIG. 4B is a diagram showing a velocity distribution.
On the other hand, FIG. 5A is a diagram showing a pressure distribution when only one short offset nozzle 5 is arranged, and FIG. 5B is a diagram showing a velocity distribution. As shown in these drawings, when only one short offset nozzle 5 is arranged, both the pressure distribution and the velocity distribution are biased. This is due to the entrainment effect of the fluid having a high flow velocity discharged from the short offset nozzle 5 and the viscosity of the fluid, and the wall surface flow that forms the swirling flow along the inner wall of the concave cylindrical chamber 3 causes friction due to the centrifugal force. It happens to gradually slow down due to the development of the boundary layer. When the plate-like body is sucked in this state, the plate-like body is inclined and sucked and held, and the state becomes unstable. When holding an ultra-thin processed (50 μm or less) semiconductor wafer, a large stress is applied to the wafer due to a bias in pressure and velocity distribution, which may cause cracks and cracks. On the other hand, if two short offset nozzles 5 are arranged point-symmetrically, the above-mentioned problem is solved, and as shown in FIG. 6, even if the flow rate per nozzle is the same, the nozzle By arranging the two in a well-balanced manner, it is possible to realize a suction force of 2.5 times or more instead of twice.
In addition, the color drawings of FIGS. 4 and 5 will be submitted separately as reference materials.

  Moreover, the short offset nozzle 5 has a shorter length than the nozzle according to the prior art in order to minimize the pressure loss in the nozzle.

  The bell mouth-like fluid passage 6 is drilled horizontally from the fluid inlet 8 formed on the side surface of the swirling flow forming body 2 to the closed end surface 7 and faces the inner peripheral surface of the concave cylindrical chamber 3. Communicating with As shown in FIG. 2A, the bellmouth fluid passage 6 communicates with the short offset nozzle 5 with a smooth curved surface, so that the loss due to separation when the fluid flows into the nozzle is greatly suppressed. be able to.

  In the non-contact conveyance device 1 having the above-described configuration, when a fluid is supplied from an air supply device (not shown) to the fluid introduction port 8, the fluid is recessed from the short offset nozzle 5 via the bell mouth fluid passage 6. It is blown into the cylindrical chamber 3. The fluid blown into the concave cylindrical chamber 3 is rectified as a swirling flow in the internal space of the concave cylindrical chamber 3 and then flows out of the concave cylindrical chamber 3. At that time, if a plate-like body is arranged at a position facing the flat facing surface 4 of the swirling flow forming body 2, the atmospheric pressure supply from the outside into the concave cylindrical chamber 3 is restricted, and the entrainment effect is achieved. Due to the centrifugal force, the density of fluid molecules per unit area gradually decreases, the pressure at the center of the swirling flow in the concave cylindrical chamber 3 decreases, and negative pressure is generated. As a result, the plate-like body is pressed by the ambient atmospheric pressure and is sucked toward the flat facing surface 4 side. On the other hand, when the distance between the flat facing surface 4 and the plate-like body approaches, the fluid discharged from the concave cylindrical chamber 3 Is limited, and the flow velocity of the fluid blown from the short offset nozzle 5 becomes slow, so that the pressure at the center of the swirling flow in the concave cylindrical chamber 3 rises and the plate-like body does not come into contact with the flat opposed surface 4 and the plate-like body The distance is kept. Further, the plate-like body is stably held in a non-contact state by the air interposed between the flat opposing surface 4 and the plate-like body.

ただし、ｐとｐ_ａはそれぞれ圧縮空気の絶対圧力と大気圧、ＱとＱ_ａは圧縮状態下での体積流量と大気圧状態に換算した体積流量であり、同一の消費流量でも圧力が相違すれば消費エネルギーが大きく異なり、これらを適切に扱う必要がある。
このエアパワーの概念を導入することにより、エネルギーの定量化において圧縮空気を電力と同様に扱えるようになる。 According to this non-contact conveyance device 1, it becomes possible to realize a significant improvement in energy efficiency and energy saving compared to the conventional non-contact conveyance device, but before explaining the specific improvement efficiency, The evaluation method will be described.
Conventionally, the energy consumption of pneumatic equipment including the non-contact conveyance device as described above is indicated by air consumption, and has been evaluated by being converted into power consumption through the specific energy of the compressor used. However, since air consumption is not directly linked to energy, it is desirable to define and quantify energy flow with compressed air flow. Therefore, in this specification, attention is paid to the energy of the flowing compressed air, and the concept of effective energy and air power is introduced in evaluating energy efficiency.
As is well known, in pneumatic equipment, compressed air is present as an energy transmission medium. The power carried by the compressed air is called air power. Air power is expressed in units of kw (kilowatts), as is electric power. Air power is defined as the effective energy flux of compressed air and is expressed by the following equation.

Here, p and p _a is the volumetric flow rate and volume flow rate converted to atmospheric pressure of absolute pressure and the atmospheric pressure, Q and Q _a respective compressed air under a compressed state, by difference pressure at the same flow consumption Energy consumption varies greatly, and these need to be handled appropriately.
By introducing this concept of air power, compressed air can be handled in the same way as electric power in the quantification of energy.

7 to 9 show the energy efficiency of the non-contact conveyance device 1 according to this embodiment with respect to the non-contact conveyance device according to the prior art (specifically, the non-contact conveyance device disclosed in JP-A-2005-51260). It is a figure which displays using the concept of air power.
First, as shown in FIG. 7, the non-contact conveyance device 1 formed with a smooth curved surface at the opening ridge angle is a non-contact conveyance device according to the related art in which the opening edge is chamfered as a result of suppressing peeling due to the ridge angle. As a result, an improvement in efficiency of 12% on average was observed. Further, as an effect (not shown), the stability of holding the plate-like body is increased as compared with the non-contact conveyance device according to the prior art.
Moreover, as shown in FIG. 7, as a result of the short offset nozzle 5 being arranged so as to face the middle of the concave cylindrical chamber 3, energy loss caused by friction due to the viscosity of the concave cylindrical chamber 3 and the fluid is suppressed, Compared to the non-contact transfer device according to the prior art in which the nozzles are arranged on the bottom surface of the concave cylindrical chamber 3, an improvement in efficiency of 21% was observed on average.

  Further, as shown in FIG. 8, the non-contact transfer device 1 in which the short offset nozzle 5 is disposed at a position away from the inner peripheral surface of the concave cylindrical chamber 3 has a large shear on the inner peripheral surface of the concave cylindrical chamber 3. Attenuation of energy due to force is avoided, and the input energy is more efficiently converted into rotational momentum. As a result, the nozzle is arranged along the inner wall of the concave cylindrical chamber 3 as compared with the conventional non-contact transfer device. An average efficiency improvement of 17% was observed.

  FIG. 9 shows a result obtained by integrating the efficiency improvements shown in FIGS. As shown in the figure, the non-contact conveying apparatus 1 showed a significant improvement in efficiency of 41% on average in comparison with the non-contact conveying apparatus according to the prior art.

  In the above description, the two short offset nozzles 5 are arranged at positions that are point-symmetric with respect to the center O of the circumference of the concave cylindrical chamber 3, but the arrangement method of the two nozzles is limited to this. There is no. Further, the number of the short offset nozzles 5 is not limited to two as in the above example, and may be any number of two or more that allows the fluid to rotate efficiently and in a balanced manner.

Second Embodiment
A second embodiment of the present invention will be described with reference to FIGS.
FIG. 10 is a perspective view showing the configuration of the non-contact transport apparatus 10 according to the present embodiment. FIGS. 11A and 11B are diagrams showing the configuration of the non-contact conveying apparatus 10, where FIG. 11A is a top view, FIG. 11B is a side view, and FIG. 11C is a bottom view. FIG. 12 is an explanatory diagram of driving of the centering mechanism 12 provided in the non-contact conveyance device 10. In the following description, components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
The non-contact conveyance device 10 according to the present embodiment is configured by using a plurality of swirl flow forming bodies 2 according to the first embodiment. Specifically, the base portion 11 and the base portion 11 are attached. The six swirling flow forming bodies 2 and a centering mechanism 12 mounted on the base portion 11 to prevent the plate-like body from being detached are provided.

  The six swirling flow forming bodies 2 are supported so that the closed end surface side is attached to the inner surface of the base portion 11 and the flat opposing surfaces 4 are all the same surface. A fluid supply port 13 is provided on the outer surface of the base 11, and a base (not shown) that communicates the fluid supply port 13 with the fluid introduction port 8 of the swirling flow forming body 2 inside the wall body. An internal passage is formed by branching from the fluid supply port 13. A centering mechanism 12 for positioning and preventing separation of the plate-like body held in a non-contact manner is mounted on the outer surface of the base portion 11. As shown in FIG. 12, the centering mechanism 12 includes six cylinders 121 whose one ends communicate with each other, and six link arms 122 whose one ends are connected to the other ends of the cylinders 121. Each of the link arms 122 is composed of six centering guides 123 suspended from the other end. Since the six cylinders 121 communicate with each other at one end thereof, they can be pressurized or depressurized by a single system of fluid. When the pressure inside the cylinder 121 is reduced by the fluid, the six centering guides 123 are driven in the central direction via the six link arms 122. Due to the movement in the center direction by the centering guide 123, the outer periphery of the plate-like body held in a non-contact manner by the non-contact conveying device 10 is regulated, and the center of the plate-like body is the center of the internal space of the base portion 11. Is positioned so as to match. On the contrary, when the inside of the cylinder 121 is pressurized by the fluid, the six centering guides 123 are driven away from the center via the six link arms 122. By the movement in the direction away from the center by the centering guide 123, the restriction on the plate-like body is released, and the plate-like body becomes free.

In the non-contact conveyance device 10 having the above-described configuration, when a fluid is supplied from an air supply device (not shown) to the fluid supply port 13, the fluid passes through a passage in the base portion 11 (not shown) and swirls. It is sent to the flow former 2. The fluid sent to each swirl flow forming body 2 is blown into the concave cylindrical chamber 3 from the short offset nozzle 5 through the fluid inlet 8 and the bell mouth fluid passage 6. The fluid blown into the concave cylindrical chamber 3 is rectified as a swirling flow in the internal space of the concave cylindrical chamber 3 and then flows out of the concave cylindrical chamber 3. Here, the swirling flow formed by each swirling flow forming body 2 has its swirling direction adjusted in advance so as not to rotate when the plate-like body is held in a non-contact manner. In the case of the non-contact transfer device 10 according to the present embodiment, three of the six swirling flow forming bodies 2 are swirled in the clockwise direction, and the remaining three are adjusted so as to swirl counterclockwise. Has been.
When the fluid flows out from the concave cylindrical chamber 3 of each swirl flow forming body 2, if the plate-like body is disposed at a position facing the flat facing surface 4 of each swirl flow forming body 2, the concave cylindrical chamber 3 The supply of atmospheric pressure from the outside to the inside is limited, the density of fluid molecules per unit area gradually decreases due to the entrainment effect and centrifugal force, the pressure at the center of the swirling flow in the concave cylindrical chamber 3 decreases, and the negative pressure Will occur. As a result, the plate-like body is pressed by the ambient atmospheric pressure and is sucked toward the flat facing surface 4 side. On the other hand, when the distance between the flat facing surface 4 and the plate-like body approaches, the fluid discharged from the concave cylindrical chamber 3 Is limited, and the flow velocity of the fluid blown from the short offset nozzle 5 becomes slow, so that the pressure at the center of the swirling flow in the concave cylindrical chamber 3 rises and the plate-like body does not come into contact with the flat opposed surface 4 and the plate-like body. The distance is kept. Further, the plate-like body is stably held in a non-contact state by the air interposed between the flat opposing surface 4 and the plate-like body. When the base portion 11 is moved in this state, the plate-like body is moved while being guided by the centering guide 123 along with the movement.

In this non-contact conveying apparatus 10, since the plate-like body is sucked by the swirling flow formed by the six swirling flow forming bodies 2, the suction force can be made extremely strong. Moreover, in this non-contact conveyance apparatus 10, since a swirl | vortex flow is formed in six places, even if it is a plate-shaped body which has a big diameter, it will be attracted | sucked over the whole. Therefore, even if the plate-like body is warped, it is possible to correct the warpage throughout. Furthermore, since the swirl flow forming body 2 similar to the non-contact conveyance device 1 according to the first embodiment is used in the non-contact conveyance device 10, the same as the non-contact conveyance device 1 according to the first embodiment. As a result, significant energy efficiency and energy saving can be realized.
In the above description, six swirl flow formations 2 are provided. However, the number is not limited to six, and an arbitrary number of two or more may be provided. The same applies to the centering guide 123.

<Third Embodiment>
A third embodiment of the present invention will be described with reference to FIGS.
FIG. 13 is a perspective view illustrating a configuration of the non-contact transport device 20 according to the present embodiment. FIGS. 14A and 14B are diagrams showing the configuration of the non-contact transport device 20, wherein FIG. 14A is a top view and FIG. 14B is a side view. FIG. 15 is an explanatory diagram of driving of the centering mechanism 22 provided in the non-contact conveyance device 20. In the following description, components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
The non-contact conveyance device 20 according to the present embodiment is configured by using a plurality of swirl flow forming bodies 2 according to the first embodiment, and specifically, a plate having a flat surface facing the plate-like body. The base 21, the six swirling flow forming bodies 2 attached to the base 21, the centering mechanism 22 provided below the base 21, and the base 21 so as to be movable. The grip part 23 is provided.
The base body 21 includes a base portion 211 and two arm portions 212 branched from the base portion 211 in a bifurcated manner. A protruding centering guide 213 is provided at the protruding end of each arm portion 212.

  The six swirl flow forming bodies 2 are supported so that the closed end face side is attached to the upper surface of the base body 21 and the flat opposed faces 4 are all the same face. A fluid supply port 24 is provided on the side surface of the grip portion 23, and a fluid (not shown) that communicates the fluid supply port 24 with the fluid introduction port 8 of the swirl flow forming body 2 corresponding to the inside of the base 21. A passage is formed by branching from the fluid supply port 24. A centering mechanism 22 is provided below the base body 21 for positioning and preventing the plate-like body held in a non-contact manner. As shown in FIG. 15, the centering mechanism 22 has a cylinder 221 provided in the grip portion 23, one end connected to one end of the cylinder 221, and two centering guides provided to the other end. The link plate 222 is configured. When the inside of the cylinder 221 is pressurized by the fluid, the two centering guides 22 are driven toward the plate-like body via the link plate 222. Due to the movement toward the plate-like body by the centering guide 223, the plate-like body held in a non-contact manner by the non-contact conveying device 20 is provided on the centering guide 223 on the link plate 222 and the protruding end of the arm portion 212. The outer periphery of the centering guide 213 is regulated and positioned. Conversely, when the pressure inside the cylinder 221 is reduced by the fluid, the two centering guides 223 are driven in a direction away from the plate-like body via the link plate 222. By the movement of the centering guide 223 away from the plate-like body, the restriction on the plate-like body is released, and the plate-like body becomes free.

In the non-contact conveyance device 20 having the above-described configuration, when a fluid is supplied from an air supply device (not shown) to the fluid supply port 24, the fluid passes through a fluid passage in the base body 21 (not shown) and rotates. It is sent to the flow former 2. The fluid sent to each swirl flow forming body 2 is blown into the concave cylindrical chamber 3 from the short offset nozzle 5 through the fluid inlet 8 and the bell mouth fluid passage 6. The fluid blown into the concave cylindrical chamber 3 is rectified as a swirling flow in the internal space of the concave cylindrical chamber 3 and then flows out of the concave cylindrical chamber 3. Here, the swirling flow formed by each swirling flow forming body 2 has its swirling direction adjusted in advance so as not to rotate when the plate-like body is held in a non-contact manner. In the case of the non-contact transfer device 20 according to the present embodiment, three of the six swirling flow forming bodies 2 are swirled in the clockwise direction, and the remaining three are adjusted so as to swirl in the counterclockwise direction. Has been.
When the fluid flows out from the concave cylindrical chamber 3 of each swirl flow forming body 2, if the plate-like body is disposed at a position facing the flat facing surface 4 of each swirl flow forming body 2, the concave cylindrical chamber 3 The supply of atmospheric pressure from the outside to the inside is limited, the density of fluid molecules per unit area gradually decreases due to the entrainment effect and centrifugal force, the pressure at the center of the swirling flow in the concave cylindrical chamber 3 decreases, and the negative pressure Will occur. As a result, the plate-like body is pressed by the ambient atmospheric pressure and is sucked toward the flat facing surface 4 side. On the other hand, when the distance between the flat facing surface 4 and the plate-like body approaches, the fluid discharged from the concave cylindrical chamber 3 Is limited, and the flow velocity of the fluid blown from the short offset nozzle 5 becomes slow, so that the pressure at the center of the swirling flow in the concave cylindrical chamber 3 rises and the plate-like body does not come into contact with the flat opposed surface 4 and the plate-like body. The distance is kept. Further, the plate-like body is stably held in a non-contact state by the air interposed between the flat opposing surface 4 and the plate-like body. When the base body 21 is moved in this state, the plate-like body moves while being guided by the centering guides 213 and 223 along with the movement.

In this non-contact conveyance device 20, since the plate-like body is sucked by the swirling flow formed by the six swirling flow forming bodies 2, the suction force can be made extremely strong. Moreover, in this non-contact conveyance apparatus 20, since a swirl | vortex flow is formed in six places, even if it is a plate-shaped body which has a big diameter, it will be attracted | sucked over the whole. Therefore, even if the plate-like body is warped, it is possible to correct the warpage throughout. Further, since the non-contact transfer device 20 is configured in a plate shape, it can freely access even the wafers in the stacked wafer cassettes that have been difficult to access. Furthermore, in this non-contact conveyance apparatus 20, since the same swirl flow formation body 2 as the non-contact conveyance apparatus 1 which concerns on 1st Embodiment is used, it is the same as the non-contact conveyance apparatus 1 which concerns on 1st Embodiment. As a result, significant energy efficiency and energy saving can be realized.
In the above description, six swirl flow formations 2 are provided. However, the number is not limited to six, and an arbitrary number of two or more may be provided. The same applies to the centering guides 213 and 223.

It is a perspective view which shows the structure of the non-contact conveying apparatus 1 which concerns on 1st Embodiment, (a) is from the diagonally lower side, (b) is the perspective view seen from diagonally upward. It is sectional drawing of the non-contact conveying apparatus 1 which concerns on the embodiment, (a) is the II sectional view taken on the line of Fig.1 (a), (b) is the II-II sectional view of Fig.1 (a). FIG. It is a figure which shows the relationship between the position of the short offset nozzle 5, and suction force. (A) is a figure which shows pressure distribution at the time of arrange | positioning two short offset nozzles 5 in point symmetry, (b) is a figure which shows speed distribution. (A) is a figure which shows pressure distribution at the time of arrange | positioning only one short offset nozzle 5, (b) is a figure which shows speed distribution. It is a figure which shows the relationship between the number of the short offset nozzle 5, and suction force. It is a figure which displays the energy efficiency with respect to the non-contact conveying apparatus which concerns on the prior art of the non-contact conveying apparatus 1 which concerns on 1st Embodiment using the concept of air power. It is a figure which displays the energy efficiency with respect to the non-contact conveying apparatus which concerns on the prior art of the non-contact conveying apparatus 1 which concerns on 1st Embodiment using the concept of air power. It is a figure which displays the energy efficiency with respect to the non-contact conveying apparatus which concerns on the prior art of the non-contact conveying apparatus 1 which concerns on 1st Embodiment using the concept of air power. It is a perspective view which shows the structure of the non-contact conveying apparatus 10 which concerns on 2nd Embodiment. It is a figure which shows the structure of the non-contact conveying apparatus 10 which concerns on the embodiment, (a) is a top view, (b) is a side view, (c) is a bottom view. It is drive explanatory drawing of the centering mechanism with which the non-contact conveying apparatus 10 which concerns on the same embodiment is provided. It is a perspective view which shows the structure of the non-contact conveying apparatus 20 which concerns on 3rd Embodiment. It is a figure which shows the structure of the non-contact conveying apparatus 20 which concerns on the embodiment, (a) is a top view, (b) is a side view. It is drive explanatory drawing of the centering mechanism 22 with which the non-contact conveying apparatus 10 which concerns on the same embodiment is provided.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 10, 20 ... Non-contact conveyance apparatus, 2 ... Swirling flow formation body, 3 ... Recessed cylindrical chamber, 4 ... Flat opposing surface, 5 ... Short offset nozzle, 6 ... Bellmouth fluid passage, 7 ... Opening edge, DESCRIPTION OF SYMBOLS 8 ... Fluid introduction port, 11 ... Base part, 12, 22 ... Centering mechanism, 121, 221 ... Cylinder, 122 ... Link arm, 222 ... Link plate, 123, 213, 223 ... Centering guide, 13, 24 ... Fluid supply port 21 ... Base, 211 ... Base, 212 ... Arm, 23 ... Gripping part.

Claims (5)

A substantially columnar body in which a concave cylindrical chamber having a circumferential inner surface is formed;
A flat end surface of the main body formed on the opening side of the concave cylindrical chamber;
A nozzle that is formed to face the inner peripheral surface of the concave cylindrical chamber, and discharges the supply fluid into the concave cylindrical chamber;
A fluid passage communicating with the nozzle and supplying a fluid into the concave cylindrical chamber through the nozzle;
The non-contact transfer device, wherein the nozzle is disposed at a position farther inward than the inner circumferential surface of the concave cylindrical chamber.   2. The non-contact transfer device according to claim 1, wherein two nozzles are arranged at positions that are point-symmetric with respect to a center of a circumference of the concave cylindrical chamber.   The non-contact conveyance device according to claim 1, wherein the nozzle is disposed in the middle of the concave cylindrical chamber.   The nozzle is provided so as to have a predetermined angle θ with respect to a tangent that is in contact with the inner circumference at the discharge point P, and this angle θ is a radius that is orthogonal to a line L1 extending from the discharge point P in the fluid discharge direction. When r1 is subtracted, the distance δ between the intersection point P2 of the radius r1 and the line L1 and the intersection point P3 of the radius r1 and the circumference of the concave cylindrical chamber satisfies δ / r1 = 5% to 25%. The non-contact transfer device according to claim 1, wherein the non-contact transfer device is set.   The opening edge of the concave cylindrical chamber has a shape that smoothly curves from the inner peripheral surface of the concave cylindrical chamber and extends to the outer edge of the concave cylindrical chamber opening. The non-contact conveyance apparatus of crab.

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