JP2006298565A - Overhead traveling vehicle system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overhead traveling vehicle system capable of confirming ID of an article on an article placement base by a relatively small number of ID readers. <P>SOLUTION: A first overhead traveling vehicle 22 provided with the ID reader 60 for reading the ID 54 of the article 50 and a communication means for communicating the read ID 54 to a control part; and a second overhead traveling vehicle not provided with the ID reader are provided. Further, a taking out means for taking out the article 50 from the article placement base is provided on the first overhead traveling vehicle 22 and ID 50 is read by the ID reader 60 in the state that the article 50 is taken out from the article placement base. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an overhead traveling vehicle system, and more particularly to inventory management of an overhead traveling vehicle system.

  The inventors have proposed to provide a buffer in the ceiling space on the side of the traveling rail of the overhead traveling vehicle (Patent Document 1). In this overhead traveling vehicle system, the overhead traveling vehicle is provided with a lateral feed unit, and the lifting drive unit is moved in the lateral direction with respect to the traveling rail to deliver the article to and from the side buffer. The inventor studied how to manage the stock of such a buffer and arrived at the present invention.

Increasing the buffer storage capacity increases the need to manage which articles are stored in which buffers. On the other hand, the buffer
・ Temporary storage of goods because the destination load port is blocked.
・ Temporary storage of items that have been transported and emptying overhead traveling vehicles for transporting express items
-It is often used for the purpose of unloading goods from the load port and waiting for them to be transported by the following overhead traveling vehicle. Moreover, by doing in this way, a conveyance operation | work can be performed flexibly and conveyance efficiency improves. However, if the buffer is operated flexibly, it becomes difficult for the controller to manage which article is stored in which buffer.

Conventional overhead traveling vehicles are not equipped with an ID reader. Also, since the buffer is a temporary storage shelf, the equipment is kept to a minimum, and no ID reader is provided. Here, it is impossible to provide ID readers for all buffers or ID readers for all overhead traveling vehicles. However, if an ID reader is provided only in a specific buffer, it is necessary to transport the article to a buffer provided with the ID reader in order to confirm the ID of the article. In this case, there is no significant difference from the current ID confirmation operation, in which an article with an unknown ID is conveyed to a stocker or inspection facility with an ID reader and confirmed there.
Japanese Patent Application No. 2004-186212

An object of the present invention is to make it possible to confirm the ID of an article on the article mounting table with a relatively small number of ID readers.
An additional problem in the invention of claim 2 is to make it possible to read the ID more reliably.
An additional problem in the invention of claim 3 is to improve the conveying ability of the overhead traveling vehicle.

  The present invention provides an overhead traveling vehicle system in which an overhead traveling vehicle travels along a traveling rail, and an article mounting table is provided along the rail to temporarily place the article, and an ID for reading the ID of the article. A first overhead traveling vehicle provided with a reader and a communication means for communicating the read ID to the control unit and a second overhead traveling vehicle not provided with the ID reader are provided, and these are both traveled together. It is characterized by running along the rail.

  Preferably, the first overhead traveling vehicle is provided with take-out means for taking out the article from the article placing table, and the ID is read by the ID reader in a state where the article is taken out from the article placing table.

  Particularly preferably, the take-out means includes a lifting platform for chucking the article and a lifting drive unit for lifting and lowering the lifting platform, and the first overhead traveling vehicle is used to take an inventory by reading the ID of the article, Carry and carry.

  In this invention, the ID of the article on the article placing table can be read by the ID reader provided in the first overhead traveling vehicle. Compared to the case where ID readers are provided on all overhead traveling vehicles or on all article mounting tables, only a small number of ID readers are provided, and the IDs of the articles are confirmed and the inventory management of the articles on the article mounting tables is performed. It can be performed. If inventory management on the article mounting table can be performed reliably, the conveyance efficiency can be improved by flexibly changing the unloading destination of the article according to the status of the load port or the condition of the article mounting table initially specified. . In addition, by providing a large number of article mounting tables, a stocker can be made unnecessary or the capacity thereof can be reduced, and direct conveyance by long distance traveling is facilitated.

  Even when the ID is provided on the back surface of the article and it is difficult to read it from a long distance, the ID can be accurately read by taking out and reading the article as in the invention of claim 2. This increases the reliability of ID reading.

  When the take-out means is configured to include the lifting platform and the lifting drive unit, the first overhead traveling vehicle can also chuck and convey the article. For this reason, the first overhead traveling vehicle can perform two kinds of operations, ID reading and article conveyance. For example, when no conveyance instruction is assigned, ID confirmation (inventory) is performed, and conveyance instruction is issued. When assigned, it carries. Preferably, the ID of the article is confirmed simultaneously with the conveyance. For this reason, even if the total number of overhead traveling vehicles is made constant and the first overhead traveling vehicle is provided, the conveyance capacity does not decrease.

  In the following, an optimum embodiment for carrying out the present invention will be shown.

  The overhead traveling vehicle system 2 of an Example is shown in FIGS. The overhead traveling vehicle system 2 is provided in a clean room such as a semiconductor factory. There is an interbay route 3 for connecting remote bays (processes) to the bay, and an intrabay route 4 is provided in each bay. The branching / merging unit 5 is a place for branching or joining such as between the routes 3 and 4, and the route boundary 6 is a boundary between the routes 3 and 4. Routes 3 and 4 are constituted by running rails, and 7 is a joint of the running rails.

  A processing apparatus 8 such as a semiconductor processing apparatus is connected along the intra-bay route 4, and 9 is a load port provided directly below the intra-bay route 4. A side buffer 10 is provided in the ceiling space on the side of the intra bay route 4, and a lower buffer 11 is provided in a ceiling space below the intra bay route 4 in a position where it does not interfere with the load port 9. Buffers 10 and 11 are examples of article placement tables.

  Two types of overhead traveling vehicles 20 and 22 travel along the routes 3 and 4, the overhead traveling vehicle 22 corresponds to the first overhead traveling vehicle, and the overhead traveling vehicle 20 corresponds to the second overhead traveling vehicle. The number of overhead traveling vehicles 20 is greater than that of overhead traveling vehicles 22. A transport controller 24 controls the entire overhead traveling vehicle system 2. A plurality of local controllers 28 are provided as lower controllers, and the overhead traveling vehicle system 2 is managed in units such as the intra-bay route 4. A production controller 26 controls production by the processing device 8 and the like, and requests the conveyance controller 24 to specify the article ID, the conveyance source (FROM), and the conveyance destination (TO), and to convey the article. Controllers may be provided in a larger number of layers.

  As shown in FIG. 2 and the like, the traveling rail 30 is provided in the ceiling space, and for example, a power supply rail 31 is provided in the lower part thereof. In order to accurately indicate the position of the load port or the like, a linear scale 32 is provided on the traveling rail 30 or the like so that it can be read by the overhead traveling vehicles 20 and 22. A mark such as a bar code 33 is provided on the power supply rail 31 or the like to instruct the overhead traveling vehicles 20 and 22 about the position of the load port and the buffer. In addition to this, the feed rail 31 may be provided with a comb mark or the like so that the overhead traveling vehicles 20 and 22 can recognize the current position. Reference numeral 35 denotes a prop of the traveling rail, and 36 and 37 denote the columns of the buffers 10 and 11.

  Hereinafter, a configuration common to the overhead traveling vehicles 20 and 22 is shown. The traveling unit 40 travels in the traveling rail 30, and the power receiving unit 41 receives power from a litz wire provided on the power feeding rail 31 by non-contact power feeding or the like, and communicates using a litz wire in addition to this. Reference numeral 42 denotes a main body frame, which is provided with a fall prevention cover 44 before and after the overhead traveling vehicles 20 and 22, 45 is a lateral feed portion, and 46 is a θ drive, which need not be provided. Reference numeral 47 denotes an elevating drive unit that elevates the elevating platform 48. Reference numeral 49 denotes a fall prevention claw which is provided at the bottom of the fall prevention cover 44 so as to be able to appear and disappear to prevent the article 50 from falling. The elevating drive unit 47, the elevating table 48, and the like are provided with a first-in product sensor (not shown) to detect the presence of the article 50 on the buffers 10 and 11 and the load port 9.

  The lateral feed unit 45 laterally feeds the θ drive 46 to the lifting platform 48 to the left side of FIG. 2 so that the article 50 can be delivered to and from the side buffer 10 provided on the left side of the traveling rail 30. The θ drive 46 rotates the elevating drive unit 47 in a horizontal plane to facilitate delivery of the article 50.

  The article 50 is a semiconductor cassette, for example, and has a cover 52 that can be opened and closed on the front surface. A flange 53 is provided on the upper part of the article 50 and is conveyed by being chucked by an elevator 48. And the barcode 54 is affixed on the lower back side of the article 50, and the ID of the article 50 is described. Note that another ID such as an RF tag may be attached to the article 50 in place of the barcode 54.

  Below, the structure provided only in the overhead traveling vehicle 22 is shown. Reference numeral 60 denotes a bar code reader which reads the bar code 54 of the article 50 and rotatably attaches it to either the front or rear fall prevention cover 44 by, for example, an arm 62. The bar code reader 60 can be moved back and forth with respect to the space between the front and rear fall prevention covers 44. The arm 62 is rotated by a rotation motor 63, and is located between a position where the fall prevention cover 44 overlaps with the fall prevention cover 44 in a side view and does not hinder the lateral movement of the article 50, and a position where the bar code 54 moves backward to read. Can rotate. In addition, when attaching ID with low directionality, such as an RF tag, to the article 50, for example, an RF tag reader may be attached to the lift 48.

  FIG. 3 shows each block of the overhead traveling vehicle 22. The overhead traveling vehicles 20 and 22 include a traveling unit 40, a power receiving unit 41, a feeder radio 68, and the like. For example, the feeder radio 68 may be provided on the upper part of the main body frame 42 to communicate with a local controller or between overhead traveling vehicles, and a signal line for communication may be provided on the power supply rail 31 or the like. The transverse feed unit 45, the θ drive 46, and the lifting drive unit 47 are provided in the overhead traveling vehicles 20 and 22, the barcode reader 66 reads the barcode provided on the power supply rail, and the linear sensor 64 is a linear scale provided on the traveling rail. Read. The traveling unit 40 to the linear sensor 64 are common to the overhead traveling vehicles 20 and 22.

  The bar code reader 60 to the bar code position checker 84 in FIG. 3 are provided only in the overhead traveling vehicle 22. The barcode reader 60 reads the barcode of the article 50. The installation determination unit 72 includes a sensor such as a laser distance meter and detects a step at the joint of the traveling rail by measuring the distance between the traveling rail and the traveling unit. The feed line sensor 74 checks the position of the litz wire holder and the litz wire on the feed rail with a contact sensor. In the acceleration sensor 76, an acceleration sensor is attached to a traveling unit of an overhead traveling vehicle or a hand of a lifting platform to measure the vibration of the overhead traveling vehicle or the vibration applied to the article. The power reception amount sensor 78 detects the amount of power received by the power reception unit from the litz wire. The communication state sensor 80 determines the quality of the communication state from the strength of the received signal at the power receiving unit 41 and the feeder radio 68. The linear scale checker 82 checks the mounting position of the linear scale on the traveling rail with a contact sensor or the like. The bar code position checker 84 checks the quality of the bar code position attached to the power supply rail. When a defect is detected by these sensors or checkers, the position of the running rail is reported to the local controller or the like.

  FIG. 4 shows the reading of the barcode 54 of the article 50 by the barcode reader 60. Since it is difficult to read the barcode 54 directly on the buffer, the article 50 is chucked by the lift 48 and pulled into the overhead traveling vehicle 22 to read the barcode. In the case of the side buffer, the transverse drive unit 45 advances the θ drive 46 to the lifting platform 48 onto the buffer, and the lifting drive unit 47 moves the lifting platform 48 up and down to load and return the article 50. When the article 50 is laterally fed, the barcode reader 60 interferes with the article 50. Therefore, the barcode reader 60 is normally retracted to the position indicated by the chain line in FIG. After moving to the space, the arm 62 is rotated and the bar code 54 is read.

  When reading the ID of the article in the lower buffer, preferably the barcode reader 60 is similarly retracted to a position overlapping the fall prevention cover 44, the elevator 48 is raised and lowered to raise the article, and then the barcode reader 60 is rotated. And read the barcode of the article. In addition, the barcode reader 60 can read the ID of the article on the load port. The article whose ID has been read is returned to its original position, or is transported to a designated position when the overhead traveling vehicle 22 receives the transport command.

  When the overhead traveling vehicle 22 reads the ID of the article, the overhead traveling vehicle 22 reports the ID of the article, its position, and its own ID to the local controller. The transport controller or the local controller includes an inventory file 90 shown in FIG. 5, and manages the inventory of articles on the buffer. The stock file 90 describes the buffer ID, the presence / absence distinction, and the article ID.

  In addition to this, preferably, the following data is described in the inventory file 90. The article on the buffer is a temporary article placed between the load port and the load port, and has a transfer source and a transfer destination. Therefore, the ID of the load port of the transfer source and the ID of the load port of the transfer destination are described. In addition, a distinction between whether or not an overhead traveling vehicle for unloading articles on the buffer has been allocated and whether or not an empty buffer has been allocated for temporary placement is described. Furthermore, it is preferable to describe the time when the article was finally carried in and out of the buffer, the ID of the overhead traveling vehicle that carried the article lastly into the buffer, and the like. In addition to this, the distinction as to whether or not the inventory has been performed since the last loading / unloading of articles into the buffer is described. Among these data, the minimum required is the ID of the buffer, the distinction between in / out load, and the ID of the temporarily placed article.

  The overhead traveling vehicles 20 and 22 are specified with the ID of the article, the transport source, and the transport destination by the transport command. Then, when the overhead traveling vehicles 20 and 22 unload the article to the buffer or the load port, they report the unloaded position and the article ID to the local controller. The inventory file 90 is constantly updated with this data. When the overhead traveling vehicle 22 reads the ID of the article, it reports it to the local controller together with the ID of the buffer. As a result, the transport controller or the local controller inventories the inventory file 90, that is, verifies the inventory file.

  In inventory, for example, a bay is specified, and the presence / absence of articles and their IDs are checked for all buffers in the bay. Alternatively, the ID is checked only for a buffer that does not interfere with other overhead traveling vehicles and that has not been inventoried. In this case, it is not necessary to take an inventory for each bay. If there is an error in the inventory file 90, it is possible that there is an error in the data of other buffers in the inventory file. For example, when an article is located in a buffer that should be empty, the buffer where the article should originally be located may be empty. Therefore, if a data error is detected, the inventory of other buffers will be inspected using the time when the article was last loaded / unloaded, the ID of the overhead traveling vehicle that performed the loading / unloading, the article transport destination, etc. except for.

  As a result, the total number of the overhead traveling vehicles 20 and 22 is about 100 to 200 and the total capacity of the buffers 10 and 11 is about 1000 to 10000 articles even in a large-scale system of about 5 to 50 overhead traveling vehicles 22. By providing, the stock on the buffer can be confirmed. Since the overhead traveling vehicles 20 and 22 have the same communication capability and traveling capability, and the ability to exchange articles with the buffer and the load port, they can coexist in the same overhead traveling vehicle system. And even if a large number of buffers are provided, inventory management can be performed with certainty, so that articles can be temporarily placed in the buffer in accordance with the conditions of the load port, etc., so that the carrying work can be performed more flexibly. If a large number of buffers are provided, a stocker at the boundary between the interbay route and the intrabay route becomes unnecessary, or the number thereof can be reduced. Furthermore, it can be directly transported between remote intrabay routes via the interbay route, and the transport time can be shortened.

  6 to 13 show the inspection of the traveling rail 30 and the power supply rail 31. The traveling rail may be an interbay route or an intrabay route. The first problem in installing the traveling rail 30 is a step at the rail boundary 7. Therefore, as shown in FIG. 6, a laser distance meter 92 is provided in front of the wheels of the traveling unit 40 in the traveling direction, and the distance from the carriage to the traveling rail 30 in the traveling unit 40 is measured. If the position of the rail joint 7 is described in the bar code 33, the bar code reader 66 can determine the position. Therefore, the installation determination unit 72 determines whether the joint is 7 or not based on the data of the barcode reader 66 and the data of the encoder of the odometer, and checks whether the interval obtained by the laser distance meter 92 fluctuates at this position. To do. In this way, the degree and position of the step are obtained and reported to a local controller or the like.

  FIG. 7 and FIG. 8 show checks on the appropriateness of the position of the litz wire 95 and the position of the holder portion on the power supply rail 31. The overhead traveling vehicles 20 and 22 are provided with a power receiving core 96 around which a coil (not shown) is wound to receive power. If the position of the litz wire 95 or the position of its holder is defective, there is a risk of contact with the power receiving core 96. Therefore, a contact detection member 97 that comes in contact with the litz wire 95 or its holder protruding from a predetermined range is provided, and attached to the power receiving unit 41 with a hinge 98, for example. When the contact detection member 97 rotates around the hinge 98, it is detected by the contact sensor 99 and used as a defective signal at the holder position. For example, the overhead traveling vehicle 22 travels upward from the bottom of FIG. 8, and the contact detection member 97 is provided on the rear side of the power receiving core 96. it can.

  9 and 10 show the configuration of the linear scale checker 82. For example, a contact detection member 100 is provided at the rear end of the linear sensor 64 in the traveling direction so that the linear sensor 64 can rotate around the hinge 101. FIG. Then, the rotation of the contact detection member 100 is detected by the contact sensor 102, and a position defect of the linear scale 32 is detected. FIG. 11 shows the detection of the position defect of the bar code 33. For example, the contact detection member 104 is provided so as to protrude upward from the main body frame 42, and is rotatable about the hinge 105. The rotation is detected by the contact sensor 106. To detect. In this way, the position defect of the barcode 33 is detected. In addition to this, it is also determined whether or not a normal reading signal can be obtained by the barcode reader 66 of the overhead traveling vehicle. Further, any sensor that detects the rotation of the contact detection members 97, 100, 104 can be used in place of the contact sensors 99, 102, 106.

  12 and 13 show the vibration detection of the overhead traveling vehicle 22 and the article 50. FIG. In the traveling unit 40, for example, driving wheels 112 are provided on the bridge 110, and wheels 113 are provided on both sides thereof. Here, an acceleration sensor 76 is provided at an appropriate position of the traveling unit 40 to detect the acceleration received by the traveling unit 40, that is, the degree of vibration. When the acceleration sensor has XYZ directionality, it is preferably provided for each direction.

  In FIG. 13, an acceleration sensor 116 is provided on the hand 115 of the lifting platform 48, and the acceleration received by the article is detected at the position of the flange 53. The acceleration sensor 116 may be provided inside the elevator 48 or the like. If the acceleration has directionality, an acceleration sensor is provided in each of XYZ directions.

  In addition to this, appropriate checks such as the strength of the received signal of the feeder radio and the strength of the received signal in communication via the litz wire are checked. In the embodiment, since the litz wire is provided on the left and right sides of the power supply rail 31, an appropriate mark such as a comb tooth mark or a bar code mark is arranged in the opposite space so that the overhead traveling vehicles 20 and 21 can read the mark. be able to. In such a case, a mechanism similar to that of the contact detection member 97, the hinge 98, and the contact sensor 100 is provided to detect whether the position of the bar code mark or the comb mark is correct and to check whether these signals can be read. A sensor may be provided.

  The overhead traveling vehicle 22 has a large level difference in the joint of the traveling rail, the mounting position of the linear scale is shifted, the vibration of the traveling portion is large, the vibration received by the article is large, the mounting position of the bar code is poor, or the bar code is If it cannot be read or if the received signal from the feeder radio is weak, this is reported to the local controller. The local controller transfers this to a transfer controller or the like, and the transfer controller outputs these maintenance data to a terminal (not shown) as it is or statistically. And according to these requests | requirements, a driving | running route can be kept favorable by maintaining the driving rail 30 grade | etc.,.

A sensor for diagnosis of the travel route such as the installation determination unit 72 is provided only in the overhead traveling vehicle 22. For this reason, cost can be reduced compared with the case where these overhead vehicles 20 and 22 are provided with these sensors. When a defect in the travel route is detected, it is preferable that another overhead traveling vehicle 22 travels in the same place to check whether the cause is on the overhead traveling vehicle 22 side or on the traveling route side. . Travel for diagnosis of the travel route may be performed separately from the transport command, or may be performed while executing the transport command.

The principal part top view which shows the layout of the overhead traveling vehicle system of an Example The front view with a partial notch which shows the overhead traveling vehicle in an Example, a side buffer, and a lower buffer Functional block diagram of the overhead traveling vehicle used in the examples The figure which shows typically reading of article | item ID by the overhead traveling vehicle in an Example. The figure which shows typically the inventory data of the buffer of the controller in an Example. The figure which shows the level | step difference detection of the running rail in an Example Cross-sectional view of the main part in the short side direction of the rail schematically showing the detection of the position failure of the feeder holder in the embodiment The figure which shows typically the detection of the position defect of the feeder holder in FIG. Sectional drawing which shows typically the detection of the position defect of the linear scale in an Example The side view which shows typically the detection of the position defect of the linear scale in FIG. Side view schematically showing detection of bar code position defect of running rail in embodiment The side view which shows typically the vibration detection of the driving | running | working part in an Example. Side view schematically showing vibration detection of a transported article in an embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Overhead vehicle system 3 Interbay route 4 Intrabay route 5 Branch junction 6 Route boundary 7 Rail joint 8 Processing device 9 Load port 10 Side buffer 11 Lower buffer 20, 22 Overhead vehicle 24 Transport controller 26 Production controller 28 Local controller 30 Traveling rail 31 Feeding rail 32 Linear scale 33 Bar code
35, 36, 37 Post 40 Running unit 41 Power receiving unit 42 Main body frame 44 Drop prevention cover 45 Horizontal feed unit 46 θ drive 47 Elevating drive unit 48 Elevating table 49 Fall prevention claw 50 Article 52 Cover 53 Flange 54 Bar code 60 Bar code reader 62 Arm 63 Rotating motor 64 Linear sensor 66 Barcode reader 68 Feeder wireless 72 Installation determination unit 74 Feed line sensor 76 Acceleration sensor 78 Power reception sensor 80 Communication state sensor 82 Linear scale checker 84 Barcode position checker 90 Stock file 92 Laser distance Total 95 Litz wire 96 Power receiving core 97, 100, 104 Contact detection member 98, 101, 105 Hinge 99, 102, 106 Contact sensor 110 Bridge 112 Drive wheel 113 Wheel 115 Hand 116 Acceleration sensor

Claims (3)

In a system in which an overhead traveling vehicle travels along a traveling rail and an article placement table is provided along the rail to temporarily place an article,
A first overhead traveling vehicle that includes an ID reader for reading the ID of the article, and a communication means for communicating the read ID to the control unit; and a second overhead traveling vehicle that does not include the ID reader. An overhead traveling vehicle system characterized in that both are installed and run along the running rail. The first overhead traveling vehicle is provided with a take-out means for taking out the article from the article placing table, and the ID is read by the ID reader in a state where the article is taken out from the article placing table. The overhead traveling vehicle system according to claim 1. The take-out means includes a lifting platform for chucking an article, and a lifting drive unit for lifting the lifting platform,
3. The overhead traveling vehicle system according to claim 2, wherein the first overhead traveling vehicle performs inventory taking by reading an ID of an article and conveyance of the article.

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