JP2004363207A - Carrier system, and conveyance vehicle and station used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform quickly transfer of goods sheet by sheet between a conveyance vehicle and a system in a clean room. <P>SOLUTION: An injection portion 24 for air tunnel which blows out clean air in the gate shape, a down flow air injection portion 26 which blows out clean air downward, and an auxiliary injection portion 28 which blows out the air in the cross direction of the door and sucks the air, are installed around the door 12 of the conveyance vehicle 4. Corresponding to the position of the conveyance vehicle 4 to the station 6, the injection portions 24, 26, 28 are operated. When the center of the doors 8, 12 enters an air tunnel of the clean air from the injection portions for air tunnel, the opening of the dorrs 8, 12 is started. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
Field of application of the invention
The present invention relates to the transfer of articles in a clean room or the like, and more particularly, to a system in which a transfer between a station and a transport vehicle is maintained in an airtight manner, a transport vehicle and a station used for the system.
[0002]
[Prior art]
[Patent Document 1] Japanese Patent Application Laid-Open No. Hei 9-133385 discloses that an airtight door is used for transfer between a carrier and a system in a clean room. Airtight doors (air locks) are provided on both the transport vehicle and the station, and the transport vehicle is brought into contact with the station and stopped so that the airtight doors are in close contact with each other. Then, a total of four doors are sequentially opened, an air curtain is formed between the carrier and the station, and articles are transferred. After the transfer, the airtight door is similarly closed, and the carrier starts.
[0003]
By the way, with the production of various kinds of semiconductors in small quantities and the enlargement of substrates with liquid crystals, single-wafer transfer in which substrates are transferred one by one has become important. In the single-wafer transfer, the substrate is transferred between the transfer vehicle and the station in a bare state. Therefore, it is important to locally create a clean environment at the time of transfer as in Patent Document 1. However, in the method of Patent Document 1, it takes time to open the airtight door in a predetermined procedure to form an air curtain or close the airtight door in a predetermined procedure, and the transport speed is reduced.
[0004]
[Problems of the Invention]
It is an object of the present invention to provide a carrier system capable of transferring articles one by one between a station and a carrier without using an airtight door (claim 1).
Another object of the present invention is to further reduce the transfer time.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a transport vehicle capable of transferring articles one by one between a station and a transport vehicle without using an airtight door (claim 3).
Another object of the present invention is to increase the speed of a transfer operation for taking out an article from a station and carrying the article into the station.
An additional object of the invention of claim 5 is to prevent the air tunnel from being disturbed by the traveling wind or the like, or from flowing backward.
An additional object of the present invention is to prevent intrusion of ambient air into the carrier.
Another object of the present invention is to provide a station capable of transferring articles one by one between a station and a transport vehicle without using an airtight door (claim 7).
[0005]
Configuration of the Invention
A transport vehicle system according to the present invention is a system for transporting articles between a transport vehicle and a station, wherein the transport vehicle transports articles between the transport vehicle and the station in sheet-by-sheet units. An air tunnel forming means for forming an air tunnel for clean air is provided between the loading means and the transport vehicle and the station (claim 1).
[0006]
Particularly preferably, a door is provided in each of the station and the transport vehicle, and the air tunnel forming means is operated at least from before the stop of the transport vehicle until the door is completely closed after starting, and the opening of the door is in the air tunnel. The door opening / closing means is provided for opening each door before stopping the carrier and closing the doors after the carrier starts moving (claim 2). Note that the air tunnel forming means may be operated at all times.
[0007]
A transfer vehicle according to the present invention is a transfer vehicle configured to transfer an article to a station from a delivery port. An air tunnel forming means for injecting clean air substantially at right angles to form an air tunnel between the station and the station is provided (claim 3).
[0008]
Preferably, a pair of the transfer means are provided so that their forward directions cross at the article transfer position at the station (claim 4).
[0009]
Also preferably, when viewed from the delivery port and the air injection position of the air tunnel forming means, an air suction means or an injection means for injecting air forward in the travel direction of the air tunnel is provided in front of the transport vehicle in the traveling direction. Item 5).
Preferably, a downflow forming means for forming a downflow of clean air from the upper portion of the delivery port is provided (claim 6).
[0010]
The station according to the present invention is a station for transferring articles from a delivery port toward a carrier, wherein the transfer means for transferring the articles in sheet-by-sheet units is substantially perpendicular to the delivery port from around the delivery port. An air tunnel forming means for injecting clean air into the air and forming an air tunnel with the carrier is provided.
[0011]
Particularly preferably, the air tunnel forming means is provided with a synchronizing means for synchronizing with the stop and start of the carrier so that the operation is started before the carrier stops and the operation is terminated after the start.
[0012]
Function and Effect of the Invention
According to the present invention, a clean air tunnel is formed between the transport vehicle and the station, and the transfer means transfers the articles in sheet units. Articles are transferred through a clean air tunnel, so they are not contaminated. For this reason, even if the articles are transferred in a sheet-by-sheet state in a bare state, and the articles are not contaminated during the transfer even if an airtight door or the like is not used (claims 1, 3, and 7).
In this specification, the term "transfer in sheet units" means that articles are transferred in a bare state without being stored in a case such as a cassette. In principle, the articles are transferred one by one. For example, two substrates may be simultaneously transferred by hand.
[0013]
If the formation of the air tunnel starts at least before the stop of the transport vehicle and continues until the door is closed after starting, each door is opened before the stop of the transport vehicle so that the door opening is included in the air tunnel. Since the doors can be closed after starting, the transfer time can be reduced (claim 2).
Note that, in this specification, a transport vehicle includes an overhead traveling vehicle in addition to a tracked truck traveling on the ground and an unmanned transport vehicle traveling on a trackless route. In the case of an overhead traveling vehicle, since the elevator is raised and lowered, stopping the carrier means stopping the elevator operation of the elevator, and starting the carrier means moving the elevator away from the station.
[0014]
If a pair of transfer means are provided so that their forward directions cross each other at the article transfer position at the station, even if there is only one article transfer position at the station, the transfer means on one of the transfer means may be used. The article can be unloaded and then loaded into the station by the other transfer means. As a result, the article transfer time can be further reduced (claim 4).
[0015]
When an air tunnel is formed while the carrier is traveling, traveling wind tends to flow backward in the air tunnel or disturb the air tunnel. Therefore, if an air suction unit or an air injection unit is provided in front of the air tunnel, the traveling wind or the like can be sucked to prevent the air tunnel from being disturbed. In addition, the running wind is pushed back by the injected air or the like, so that the air tunnel can be prevented from being disturbed.
In addition, when the clean air downflow is formed from the upper portion of the transfer port, it is possible to prevent dust adhering to the door from blowing off and intrusion of dust into the inside of the transport vehicle.
[0016]
The air tunnel forming means and the transfer means are provided, for example, on the transport vehicle side, but may be provided on the station side when the transport vehicle is an overhead traveling vehicle and it is difficult to provide these facilities. Also, for a transport vehicle traveling on the ground, a means for forming an air tunnel or a transfer means may be provided on the station side. In this case as well, an air tunnel of clean air is formed between the station and the transport vehicle, and articles are transferred in sheet units so as to pass through the air tunnel.
[0017]
【Example】
1 to 10 show an embodiment and a modification thereof. 1 to 7 show a first embodiment, reference numeral 2 denotes a carrier system, and reference numeral 4 denotes a ground traveling carrier, which may be tracked or trackless. The method of controlling the traveling of the transport vehicle 4 is arbitrary. A pair of walls 5, 5 may be provided on both sides of the traveling path of the transport vehicle 4, and the walls 5 may cover the entire surface on both sides of the traveling path, or may be provided only around the station 6. Reference numeral 8 denotes a door provided in the station 6, which opens from the center in the left-right direction in the figure, for example. Reference numeral 10 denotes a control unit of the station 6. The transport vehicle 4 is provided with a door 12, which is likewise opened from the center thereof back and forth in the traveling direction. Reference numeral 14 denotes a control unit of the transport vehicle 4, and reference numerals 16 and 18 denote communication means for communicating between the control units 10 and 14 by, for example, infrared communication. The communication method between the control units 10 and 14 is arbitrary.
[0018]
The transport vehicle system 2 of the embodiment is used for transporting a semiconductor substrate, a liquid crystal substrate, and the like in a clean room on a single wafer basis. In the case of a semiconductor substrate, for example, it is assumed that a wafer of 8 to 12 inches is transferred, and in the case of a liquid crystal substrate, it is assumed that a large substrate of, for example, about 1 m × 2 m is transferred. The station 6 is a station as a loading / unloading port of each processing facility.
[0019]
The transport vehicle system 2 is used for in-process transport in a clean room, and the overhead traveling vehicle system shown in FIGS. 8 to 10 is used for inter-process transport. Reference numeral 20 denotes a floor of a clean room, which is provided with a grating so as to suck downflow from the ceiling of the clean room.
[0020]
An FFU (filter fan unit) 22 or the like is provided on the ceiling of the transport vehicle 4 or the like, so that clean air can be injected from inside the transport vehicle 4 or from the injection units 24 to 26. A gate-shaped (gate-shaped) air tunnel injection section 24 is provided around the door 12, from which clean air is blown toward the station 6 substantially at right angles to the side surface of the vehicle 4. Further, a downflow air injection unit 26 is provided near the upper portion of the door 12 so as to inject clean air downward along the door 12. The clean air from the air tunnel injection unit 24 forms an air tunnel between the transport vehicle 4 and the station 6. The air from the down-flow air jetting unit 26 removes dust adhering to the door 12 and prevents the dust adhering to the door from entering the inside of the transport vehicle 4 when the door 12 is opened. At the same time, a downward air curtain is formed at the opening of the door 12 to prevent the surrounding air from entering the transport vehicle 4 and to discharge dust in the air tunnel from below to the outside of the air tunnel. In each figure, the flow of clean air is indicated by a solid line, and the flow of normal air (particularly unpurified air) is indicated by a broken line.
[0021]
When the carrier starts to form an air tunnel while traveling, the air displaced by the traveling of the carrier 4 travels around the vehicle body as the traveling wind and tries to disturb the air tunnel. On the other hand, when the surrounding air is sucked in front of the air tunnel in the traveling direction, or when the air is jetted obliquely forward from the front of the air tunnel, the traveling wind and the like can be pushed back. The auxiliary injection unit 28 is a member for this purpose. In the embodiment, the auxiliary injection unit 28 is provided before and after the door 12, and the injection unit 29 and the suction unit 30 are provided so that the air sucked by the suction unit 30 does not particularly pass through FFU or the like. The injection is performed obliquely forward from the portion 29. At least one of the ejection unit 29 and the suction unit 30 may be provided, and may be provided at least in front of the door 12, not in the front and rear direction of travel.
[0022]
As shown in FIG. 3 and the like, the door 12 is formed of a pair of front and rear doors along the traveling direction, and is moved along the side surface of the vehicle body, or is wound up using a film-like door. Open and close symmetrically around the center of the vehicle in the front and rear direction of travel. The moving direction of the door 12 is indicated by a white arrow in FIG. Similarly, the door 8 of the station 6 opens and closes symmetrically with respect to the center.
[0023]
To explain the transfer means, as shown in FIG. 4 and the like, the transport vehicle 4 is provided with a turntable 40 with a lifting platform, and a pair of SCARA arms 42 and 43 are provided on the turntable. The hand 44 at the tip of the SCARA arms 42 and 43 is provided with, for example, a suction hole 45 so that the wafer 46 can be sucked and held. Numeral 47 denotes a mounting position of the articles in the station 6. The forward and backward movement directions of the hands 44, 44 are slightly inclined with respect to the width direction of the vehicle of the carrier 4 so that they cross at the mounting position 47. . As a result, articles can be transferred to the placement position 47 using either of the SCARA arms 42 and 43. The carrier 4 is provided with a buffer 48 so that an appropriate number of wafers 46 such as 12-inch semiconductor substrates can be accommodated.
[0024]
FIG. 5 shows an air tunnel between the carrier 4 and the station 6. The distance between the side surface of the carrier 4 and the station 6 at the time of stop is made as small as about 1 to 10 cm, and the length of the air tunnel is shortened to prevent the surrounding air from entering the air tunnel. In addition, the air in the air tunnel can be easily replaced with clean air.
[0025]
FIG. 5 shows a state in which the doors 8 and 12 are fully opened, the openings of the doors 8 and 12 are the delivery ports of the articles, and the air tunnel injection unit 24 is in a gate shape (gate shape) around it. As shown in ()), an air injection section 25 for clean air may be provided below the gate. The reason why the air injection unit 25 is provided is to prevent the traveling speed of the transporting vehicle 4 from being high, and to prevent an airflow hoisting from below from entering the air tunnel. A downflow air injection unit 27 is also provided on the station 6 side to inject clean air downward along the transfer port on the station side so as to prevent the surrounding air from entering the station 6. Is also good.
[0026]
Since an air tunnel is formed in a slight gap between the carrier 4 and the station 6, ambient air hardly enters the air tunnel. Since the wall 5 exists around the station 6, the clean air flows along the wall 5 from the end of the air tunnel, thereby more reliably preventing the intrusion of the ambient air into the air tunnel. A loop of normal air flow from the auxiliary injection section 28 is formed along the front and rear direction of the air tunnel, and the air tunnel is more reliably separated from the surrounding air. In addition, downward clean air is injected from the downflow air injection units 26 and 27, and dust adhering to the surfaces of the doors 12 and 8 is taken into the transport vehicle 4 and the station 6 when the doors are opened. To prevent that. Further, a part of the clean air from the air tunnel injection unit 24 and the downflow air injection unit 26 is injected obliquely downward so that the clean air is filled in the air tunnel.
[0027]
As a result, an air tunnel is formed that is reliably shut off from the surrounding air, and the air in the air tunnel is clean and does not become contaminated even when the wafer is transferred in a bare state. Note that it is assumed that clean air is flown, for example, in a downflow manner from an outlet (not shown) in the transport vehicle 4 and the station 6.
[0028]
FIG. 6 shows the cross sections of the nozzles in the injection units 24 to 27. The meshes 51, 52, and 53 are meshes, the mesh 51 on the right is coarse, the mesh 52 on the center is slightly fine, and the mesh 53 on the left. Has even finer eyes. As a result, in the case of FIG. 6, the clean air sent from the right side is converted into a uniform laminar flow while passing through the meshes 51 to 53. In other words, creating an air tunnel with a uniform laminar flow has a greater effect of blocking the surrounding air than creating an air tunnel with a high flow rate and a large flow rate. For this reason, a plurality of meshes are provided in the nozzle, and the mesh is made finer from the upstream side to the downstream side. Instead of stacking a plurality of meshes, a mesh may be appropriately selected and used depending on a position in the ejection unit.
[0029]
FIG. 7 shows a timing chart of the embodiment. The carrier 4 starts decelerating toward the station 6. Assuming that the required time from the start to the stop of deceleration is, for example, about 1 to 4 seconds, air is injected from the injection units 24 to 28 during the latter half of about 0.5 to 2 seconds to form an air tunnel. The start of the injection is performed based on the elapsed time from the start of the deceleration, the position recognition of the carrier with respect to the station, and the like. When the center of the door on the station side enters the clean air tunnel, the door on the station side starts to open. At the same time, the door on the carrier side starts to open. As a result, almost simultaneously with the stop of the transport vehicle, the doors of both the station side and the transport vehicle side are open. Next, almost simultaneously with the start of the carrier, the doors on the station side and the carrier side are started to be closed, and the doors are completely closed before the center of the station side door leaves the air tunnel. Then, after the door is completely closed, the injection of air is stopped.
[0030]
From the viewpoint of the operation of the transfer device, for example, while the carrier is running, the wafer to be transferred is taken out of the buffer using one arm. Next, when the turntable is turned and the carrier stops, the wafer is taken out of the station by using the other arm (arm 2), and then the arm (arm 1) from which the wafer is taken out from the buffer is extended to supply air to the station. Place. Thereafter, the arm 1 is returned to rotate the turntable, and the wafer is placed on the buffer by the arm 2. In FIG. 7, the transfer of the wafer from the buffer is performed while the carrier is running, but may be performed while the carrier is stopped.
[0031]
In the embodiment, the walls 5 are provided on both sides of the traveling path of the carrier, but may be provided only near the station. Further, although the door is closed while the carrier is traveling, the door may be kept open and an air tunnel for clean air may be always formed to prevent the intrusion of ambient air into the carrier. Alternatively, the wall 5 may be provided on both sides of the traveling path, and the carrier may always form an air tunnel for clean air and further open and close the door. Although a scalar arm is used as the transfer means, other transfer means may be used. When transferring a large liquid crystal substrate or the like, one transfer means is arranged instead of a pair of transfer means. do it. Whether or not to provide the air injection unit 25 in FIG. 5 is optional, and whether or not to provide the station side downflow air injection unit 27 is also optional. In the embodiment, the air injection unit is provided on the transport vehicle side, but may be provided on the station side, and an air tunnel may be formed from the station side to the transport vehicle. In this case, the injection units 24 to 28 may be provided in the station. Further, the transfer device is provided on the transport vehicle side, but may be provided on the station side.
[0032]
8 to 10 show an embodiment relating to an overhead traveling vehicle 62 for transporting between processes. Reference numeral 60 denotes a traveling rail, 64 denotes a hoist, and 66 denotes a lift. The lift 66 is provided with a door that is opened, for example, by being wound up, and FIG. 8 shows a state where the door is fully opened. In addition, it is preferable that the lifting platform 66 is provided with, for example, an FFU 68, and the downflow air injecting section 70 injects a downflow of clean air toward an article delivery port (opening of a door) of the lifting platform 66. Reference numeral 72 denotes a station, and the elevating table 66 descends to and stops on the table 73 of the station 72, and 74 denotes an air tunnel injection unit which blows clean air similarly to the air tunnel injection unit 24. Reference numeral 76 denotes a downflow air injection unit that causes the clean air to flow downward toward the lower side of the delivery port of the station 72. Reference numeral 78 denotes a scalar arm as an example of a transfer unit, which transfers the wafer 46 in the lift 66. Note that, for example, a pair of SCARA arms 78 may be arranged in the station 72 so that the unloading of the processed wafer and the loading of a new wafer can be performed continuously.
[0033]
8 to 10 also provide a clean air air tunnel between the elevator and the station, and use the down-flow clean air to prevent ambient air from entering the elevator and the station. The points are the same.
[0034]
FIG. 10 shows the height position of the elevator and the timing of the ejection of the clean air and the opening and closing of the door. When it is detected by the position recognition that the elevating platform has descended toward the station and has descended to the predetermined height, formation of an air tunnel and injection of downflow air are started, and the lower end of the door enters the air tunnel. Then, the door on the elevator side is rolled up, for example, upward and opened, and at the same time, the door on the station side is started to open. In this way, the door is fully opened almost simultaneously with the stop of the elevator, and the article is transferred. When the elevator starts to ascend, the door starts to close, and while the lower end of the elevator door is in the air tunnel, the door of the elevator is closed. When the door is closed, the injection of clean air is stopped.
[Brief description of the drawings]
FIG. 1 is a plan view of a main part of a transport system according to an embodiment; FIG. 2 is a side view of a transport vehicle according to an embodiment; FIG. 3 is a plan view of a transport vehicle according to an embodiment; FIG. FIG. 5 is a plan view schematically showing an air flow in the embodiment, in which (A) is a plan view, (B) is a side view, and (C) is a front view. It is.
FIG. 6 is a diagram schematically showing an air injection nozzle in the embodiment. FIG. 7 is a timing chart of the embodiment, wherein 1) is a speed pattern of a transport vehicle, 2) is air injection, and 3) is a station. 4) shows the opening / closing of the side door and the transfer operation.
FIG. 8 is a front view showing an elevator of an overhead traveling vehicle according to a second embodiment with a door opened. FIG. 9 is a diagram illustrating ejection and transfer of clean air from a station according to the second embodiment. FIG. 10 is a timing chart of the second embodiment, wherein 1) is the height position of the elevator, 2) is the air ejection pattern, and 3) is the opening / closing of the door of the elevator. Indicates a pattern.
[Explanation of symbols]
2 Car carrier system 4 Car carrier 5 Wall 6 Station 8, 12 Door 16, 18 Communication means 10, 14 Control unit 20 Floor 22, 68 FFU (filter fan unit)
24 Air Tunnel Injection Unit 25 Air Injection Unit 26, 27 Downflow Air Injection Unit 28 Auxiliary Injection Unit 29 Injection Unit 30 Suction Unit 40 Turntable 42, 43 SCARA Arm 44 Hand 45 Suction Hole 46 Wafer 47 Placement Position 48 Buffer 50 Nozzles 51 to 53 Mesh 60 Running rail 62 Overhead running vehicle 64 Hoist 66 Lifting table 70, 76 Downflow air injection section 72 Station 73 Base 74 Air tunnel injection section 78 Scalar arm

Claims (7)

In a system in which articles are transferred between a carrier and a station,
Transfer means for transferring articles in sheet units between the carrier and the station; and an air tunnel for forming a clean air air tunnel between the carrier and the station. A transport system comprising a forming unit. A door is provided at each of the station and the transport vehicle, and the air tunnel forming means is operated at least before the stop of the transport vehicle until the door is completely closed after starting, so that the opening of the door is included in the air tunnel. 2. The conveyance according to claim 1, further comprising door opening / closing means for opening each door before the stop of the conveyance vehicle and closing each door after the start of the conveyance vehicle. system. In a transport vehicle that transfers goods to the station from the delivery port,
A transfer means for transferring articles in sheet units, and an air tunnel formation for injecting clean air from the periphery of the transfer port substantially perpendicularly to the traveling direction of the carrier to form an air tunnel between the transfer station and the station. And a vehicle. 4. The transport vehicle according to claim 3, wherein a pair of said transfer means are provided, and their forward directions cross at an article transfer position at a station. When viewed from the transfer port and the air injection position of the air tunnel forming means, an air suction means or an injection means for injecting air forward in the travel direction of the air tunnel is provided forward of the transport vehicle in the traveling direction. The carrier according to claim 3 or 4. The transport vehicle according to any one of claims 3 to 5, further comprising downflow forming means for forming a downflow of clean air from above the transfer port. At a station for transferring goods from the delivery port toward the carrier,
Transfer means for transferring articles in sheet-by-sheet units, and air tunnel forming means for injecting clean air from the periphery of the delivery port to the delivery port substantially at right angles to form an air tunnel between the delivery vehicle and the delivery vehicle And a station.

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