JP4172464B2 - Conveyor cart system - Google Patents

Description

  The present invention is a clean room of a manufacturing factory for semiconductors, liquid crystal display devices, etc., and a processing object (a semiconductor wafer or a glass substrate of a liquid crystal display device) is placed on a number of stations (a place where various processing and processing are performed on the processing object). The present invention relates to a transport cart system that transports by a cart that automatically travels in an unmanned state.

  With the progress of the semiconductor and liquid crystal industries, there is a demand for a transport cart system that is more sophisticated, efficient, and capable of quickly transporting a processing object to a target station.

  The thing of patent document 1 is proposed as what responds to such a request | requirement.

  This transport cart system is a transport path in which an intrabay (traveling loops 20 to 25 in Patent Document 1) and an interbay (traveling loops 2 to 3 in Patent Document 1) are closed until then. Transfer of the processing object is performed via a transfer warehouse as a buffer (in Patent Document 1, a stocker), and the cart can be moved back and forth between the two bays so that the processing object can be transferred via the transfer warehouse. Therefore, it is possible to speed up the transportation by eliminating the cost and to reduce the cost of the system by eliminating the need for a transfer warehouse.

However, in this transport cart system in which a large number of carts go back and forth between a plurality of bays (loops), a transport command is sent to the cart that optimally meets the transport requirements in consideration of carts entering from other bays. Although it is necessary to do so, no such consideration has been made.
Japanese Patent No. 3508130

  The present invention is intended to solve the above problem, and in a system in which a large number of trolleys move back and forth between a plurality of bays (loops), the trolleys entering from other bays are also taken into account, and is optimally suited for transport requirements An object of the present invention is to provide a transport cart system that issues a transport command to a corresponding cart.

  The transport cart system according to claim 1 is a transport cart system having a plurality of zones, wherein a zone controller is provided for each zone, and each zone controller has a station that needs to transport an article within the zone managed by the zone controller. A cart allocating means for allocating a conveyance command to a cart that is present in the zone and that arrives at the station first and can grasp a load when it occurs is provided.

The transport cart system according to claim 1 is further characterized in that the cart allocation means repeats the cart allocation operation every predetermined period.

In the transport cart system according to claim 1 , the cart assigning unit further performs the transport command separately for arrival at a target station and transport of an article from the station , When a cart that arrives at a station and can grab a load is newly generated, a movement command that has already been assigned to another cart is assigned to the new cart redundantly .

The transport cart system according to claim 1 is characterized in that the cart allocation means is a cart that can also allocate a cart newly entered in a zone managed by the cart allocation means.

  According to the transport cart system of the first aspect, the transport request can be quickly processed with a simple configuration of the cart allocation means.

According to the transport cart system according to claim 1, it is possible to assign an appropriate cart according to the latest state in accordance with the characteristics of the system that changes every moment, and to operate the system more efficiently. .

According to the transport cart system of claim 1, further , by performing the command in detail , the system can be operated without changing the command according to the latest state in accordance with the characteristics of the system that changes every moment. It can be operated more efficiently.

According to the transport cart system according to claim 1, the cart can be appropriately allocated according to the latest state corresponding to the characteristics of the system in which the cart enters from another zone, and the system is more efficient. It can be used well.

  Hereinafter, embodiments (examples) of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall layout diagram showing an example of a transport cart system of the present invention, FIG. 2 (a) is a diagram conceptually showing a control system of the transport cart system of FIG. 1, and (b) is a feeder of (a). FIG. 3C is a detailed view of the main part of the wireless means, FIG. 3C is a detailed view of the main part of the zone controller of FIG. 3A, and FIG. 3 is an explanatory view of the function of the cart allocating means of FIG.

  This transport cart system 10 is a clean room of a manufacturing plant for semiconductors, liquid crystal display devices, etc., and processes objects (semiconductor wafers and glass substrates of liquid crystal display devices) into a number of stations (processing objects are processed and processed in various ways. It is used for transport by a cart that automatically travels between unmanned locations.

  The configuration includes at least a large number of carts 1 for transferring a processing object, a transport path 2 along which the carts 1 move, a certain range (hereinafter referred to as a “zone”. The range surrounded by a dotted line in FIG. 1. The zone controller (ZCU) 3 that controls a plurality of carriages 1 traveling on the conveyance path 2 and a communication line 4 for performing wireless communication from the zone controller 3 to the carriages.

  Furthermore, the transport cart system 10 includes feeder radio means 5 (see FIG. 2) that enables radio communication between the zone controller 3 and the plurality of carts 1 via the communication line 4, and supplies power to the traveling cart 1. A contact power supply means 6 (see FIG. 2) and an integrated controller 7 for controlling a plurality of zone controllers 3 are provided.

  As described above, the object to be processed is a semiconductor wafer or a glass substrate of a liquid crystal display device. In practice, however, the processing object is transported in units of cassettes that can accommodate a predetermined number of semiconductor wafers. A conveyance object may be called a cassette instead of a processing object.

  The cart 1 is roughly classified into two types, a ground traveling type and an overhead traveling type. Here, the overhead traveling type will be described as an example. With the overhead traveling type, there is no possibility that a person exists near the traveling route, the vehicle can travel at a higher speed, and the conveyance speed can be increased.

  In this example, the conveyance path 2 is installed on the ceiling, and is configured such that the carts 1 can enter each other through a larger loop through a larger loop. Stations ST for performing various treatments on the object to be treated are installed at necessary places on the transport path 2.

  In FIG. 1, the number of carriages 1, the shape of the conveyance path 2, and the number of stations ST are exemplarily shown as being limited. However, a large number of carriages are complicatedly installed in the implementation. Is. In addition, a number of shortcuts (shortcuts) 2a are provided on the conveyance path 2, and a travel route can be selected according to the situation.

  As shown in FIG. 1, the communication line 4 is provided so as to be completely along the conveyance path 2, and is engaged with the carriage 1 traveling on the conveyance path 2 while the carriage 1 is stopped and traveling. Wireless communication is possible in close proximity.

  A communication control system of the transport cart system 10 will be described with reference to FIGS.

  The cart 1 includes a central processing unit (CPU) and includes a cart controller (DCU) 1a that can independently perform various controls and processes.

  The feeder wireless means 5 that enables communication between the carriage 1 and the zone controller 3 processes communication between the communication line 4 constituted by parallel two-wire feeder lines and between the zone controller 3 and the communication line 4. Installed on the carriage 1 so as to maintain a certain close distance to the parent modem (M) 5a, the slave modem (M) 5b that processes communication between the carriage 1 and the communication line 4, and the communication line 4. The antenna 5c is provided.

  The communication line 4 used in the feeder wireless means 5 is practically limited in the length of the communication line 4 of one channel, and although not shown in the figure, it is actually different from each other. A communication line 4 of a predetermined length of the channel is installed along the shape of the transport path 2 through a certain gap.

  In addition, one zone has a range in which communication can be covered using three communication lines 4 having a predetermined length, and the communication lines 4 of these three channels are controlled by a single zone controller 3. .

  Although the feeder radio means 5 performs the proximity communication, there are limitations as described above. Therefore, the communication lines 4 of different channels can be installed along the transport path 2 as close to each other as communication is not interrupted. At the same time, there is no interference with the cart 1 passing through the communication line 4 of another channel, and there is a characteristic that communication is always possible only with the cart 1 passing through the communication line 4 of that channel. It is suitable as a communication means between the cart 1 and the zone controller 3 in such a transport cart system 10.

  The communication means is not limited to the feeder wireless means 5 as long as it has similar characteristics.

  The non-contact power supply means 6 includes a power supply line 6a for supplying power, a control panel (SCPS panel) 6b, and a power receiving coil (not shown) provided on the carriage 1 side.

  The power supply line 6 a is installed so as to be completely along the transport path 2. By supplying an alternating current to the power supply line 6a, power can be received by electromagnetic induction by a power receiving coil provided in the carriage 1 so as to be close to the power supply line 6a without contact.

  Such a non-contact power supply means 6 is suitable for a clean room because there is no contact portion between the power line 6a and the carriage 1 and no dust is generated due to the contact as compared with the conventional trolley power reception.

  However, the length of one power supply line 6a is limited to a certain length (80 meters in this example), and the number of carts 1 that can be supplied by one power supply line 6a is a predetermined number (this example). Then, there is a limitation of 20 to 30).

  Therefore, the system 10 is constructed in consideration of such restrictions. In other words, the zone controller 3 grasps which power supply line 6a each carriage is running, and controls so that the number of carriages traveling on one power supply line 6a does not exceed the predetermined number. Yes.

  Note that the power supply line 6a having a predetermined length is installed along the transport path 2 via a joint at regular intervals, and the carriage 1 may not be supplied with power at the joint. is there.

  Therefore, in the present system 10, a pair of power supply lines 6a are laid along the conveyance path 2, and correspondingly, a pair of power receiving coils on the cart 1 side are also provided as a pair of left and right power supply lines 6a. To prevent the power from being interrupted by preventing the joints from coming to the same travel position.

  The cart 1 includes travel driving means other than those shown in FIG. 2B, stores map data (data necessary for self-traveling the transport path 2) in a nonvolatile memory, and When a transfer from one station ST to another station ST is instructed, the user can determine the travel route and travel.

  At this time, the carriage 1 travels while reading a position marker provided on the conveyance path 2 and grasping in which zone of which zone of the entire conveyance path 2 the self is located.

  As described above, the distributed processing system in which only the starting point and the ending point of conveyance are given to the carriage 1 and the control such as the determination of the travel route is left to the carriage 1 side reduces the load on the zone controller 3 and the like. For this reason, in the present system 10 in which the carriage 1 freely moves over the zone by self-judgment, this has a higher degree of freedom and flexibility of the system.

  In addition, such a distributed processing system is, for example, that when it is performed on the side of the zone controller 3, for example, it is possible to control a large number of carts 1 that independently run at high speed and may enter and exit the zone. This is because a so-called supercomputer is required, but with the above-described methods, control can be performed with a so-called personal computer.

Here, the zones in the system 10 are named zones A to H as shown.
Of these zones A to H, zones A to F correspond to conventional intrabays or intra-process transport paths, and zones G and H correspond to conventional interbays or inter-process transport paths.

  In this transport cart system, a large feature is that a large number of carts can go back and forth between the plurality of zones A to H under the system conditions as described above. When assigning the optimum cart 1 to the transport request, it is necessary to assign the cart in consideration of the cart 1 entering from another zone.

  For this reason, as shown in FIG. 2C, the zone controller 3 is provided with a cart allocating means 3b in addition to the essential central processing unit (CPU) 3a. Hereinafter, the cart assignment means 3b will be described.

  In FIG. 2C, the cart allocating means 3b is described as a separate hardware element from the central processing unit 3a. However, in practice, a program that exhibits the function of the trolley allocating means 3b is generally used. Is held in the zone controller 3 and is executed by the central processing unit 3a, thereby executing the function of the cart allocating means 3b.

  First, the outline of this basic function is summarized as follows.

  (1) When the station ST that needs to be transported in the zone managed by the zone controller 3 is generated, the cart allocating means 3b arrives at the station at the earliest and grasps the load. Assign a transport command to a possible cart 1.

  (2) The cart allocation means 3b repeats the cart allocation work every predetermined period.

  (3) The cart allocating means 3b divides the conveyance command into movement to the target station ST and conveyance of articles from the station ST.

  (4) The trolley allocating means 3b is a trolley that can also be allocated to a trolley newly entered in the zone to be managed.

  Hereinafter, this will be described in detail with reference to FIG. FIG. 3 is an enlarged view of a connecting portion between the zone G (inter-process conveyance path) and the zone D (in-process conveyance path) of the conveyance path 2 in FIG. 1 and needs to be explained as compared with FIG. Above, there are added parts and omitted parts.

  In FIG. 3, a cassette that accommodates an object to be processed such as a semiconductor wafer is denoted by symbol K. Therefore, as a general rule, the carriage 1 (# 2) and the carriage 1 (# 3) loaded with the cassette K cannot newly transport the cassette K, and the carriage 1 (# 1) not loaded with the cassette K is an empty carriage. The cassette K can be newly conveyed.

  First, since cart allocation is a problem of control within a zone, it is basically performed by the zone controller 3 provided in each zone.

  In the traveling state of the carriage 1 as shown in FIG. 3, a transport request to the station ST (# 2) is sent from the integrated controller 7 to the zone controller 3. On the other hand, the cart allocating means 3b of the zone controller 3 searches for a cart that can be allocated in the upstream direction from the station ST (# 2) as indicated by a one-dot chain line arrow.

  As a result, the trolley allocating means 3b indicates that the trolley 1 (# 1) of the trolley 1 (# 1), trolley 1 (# 3),... Yes, it is determined that the vehicle arrives at the station ST (# 2) first, and only the movement command is given to the carriage 1 (# 1) among the conveyance commands to the station ST (# 2).

  The cart 1 (# 1) that has received this movement command starts traveling with the station ST (# 2) as the destination.

  The trolley allocating means 3b periodically repeats the trolley allocation. When the trolley allocation is repeated, the trolley 1 (# 2) enters the zone D from the zone G as compared with the state of this figure, and the station ST Assume that (# 1) is the destination.

  In this case, the trolley allocating means 3b assumes that the newly entered trolley 1 (# 2) is also a trolley in its own zone D and can be allocated. Then, if it is understood that the cart 1 (# 2) is unloaded at the station ST (# 1), becomes an empty cart, and arrives at the station ST (# 2) before the cart 1 (# 1), a new one is obtained. A movement command is also assigned to the cart 1 (# 2).

  On the other hand, when the carriage 1 (# 2) is intended for a station ST (not shown) downstream from the station ST (# 2), the movement command is not assigned to the carriage 1 (# 2).

  Since the cart allocation means 3b repeats the cart allocation periodically, the cart allocation corresponding to the cart traveling state in the changing zone in a timely manner can be performed, and the transport request can be processed more quickly. it can.

  According to such a cart allocation method, the cart allocation is performed in response to an ever-changing traveling situation such as when the cart 1 stops due to some accident or when any one of the shortcuts 2a is congested. be able to.

  Now, among the transport instructions of the cart allocating means 3b, the command of transporting articles (grabbing, transporting to the target station, unloading at the station) from the station ST (# 2) is the station ST (# 2). This is performed separately from the movement command to.

  In other words, from the fact that the truck 1 (# 2) will soon arrive at the station ST (# 2) or that there has already been a report that it has arrived, the carriage 1 (# 2) will receive a message from the station ST (# 2). Carry out an article conveyance command.

  When the movement command to the station ST (# 2) and the article conveyance command from the station ST (# 2) are assigned to the cart 1 (# 1) at a time, the cart 1 (# 1) that executes the command ) Is changed to the cart 1 (# 2), it is necessary to cancel the command assigned to the cart 1 (# 1), which complicates the communication sequence.

  However, if the commands are separately assigned, the carriage 1 is not assigned even if the carriage 1 (# 1) arrives at the station ST (# 2), and another movement instruction or the like is assigned. It is only necessary to assign a movement command to (# 2), and the communication sequence can be simplified.

  Thus, according to this transport cart system, the following effects can be obtained corresponding to the above (1), (2), (3), and (4).

  It should be noted that a priority is given to the station ST in accordance with the degree to which the carriage 1 does not arrive (waiting time, etc.) for the station ST that has received the transport request, and a higher priority is given to a plurality of transport requests. If priority is given to the transport command for the station ST, the waiting time for each station ST can be optimized, and the transport request can be processed more quickly.

  (1) A transport request can be quickly processed with a simple configuration of a cart allocation means.

  (2) Corresponding to the ever-changing characteristics of the system, appropriate carts can be allocated according to the latest state, and the system can be operated more efficiently.

  (3) By performing the command in detail, it is possible to operate the system more efficiently without requiring re-commanding according to the latest state in accordance with the system characteristics that change every moment.

  (4) Corresponding to the characteristics of the system that changes from moment to moment, and there are trolleys from other zones, appropriate trolleys can be allocated according to the latest state, and the system can be operated more efficiently. .

  The specific configurations described above are not limited to those described herein, but include equivalent or equivalent ones, or ones easily replaceable by those skilled in the art.

  The transport cart system of the present invention requires cart allocation with higher efficiency when a processing object is automatically transported between many stations in an unattended state in a clean room of a manufacturing plant such as a semiconductor or a liquid crystal display device. Can be used in all industrial fields.

Overall layout diagram showing an example of a transport cart system of the present invention (A) is a diagram conceptually showing a control system of the transport cart system of FIG. 1, (b) is a detailed view of the main part of the feeder radio means of (a), and (c) is the main part of the zone controller of (a). Detail drawing Explanatory drawing about the function of the cart allocating means in FIG.

Explanation of symbols

1 cart 2 transport path 2a shortcut 3 zone controller 3b cart allocation means 4 communication line 5 feeder radio means 6 non-contact power supply means 7 integrated controller 10 transport cart system ST station

Claims (1)

A transport cart system having a plurality of zones, wherein a zone controller is provided for each zone, and when each zone controller generates a station that needs to transport articles in the zone managed by the zone controller, A carriage allocating means for allocating a conveyance command to a trolley that is seated and that arrives at the station first and can grasp the load ;
The cart allocating means repeatedly performs the cart allocating operation every predetermined period, and the trolley that newly enters the zone managed by the trolley is also a cart that can be allocated, and the transfer command is sent to the target station. And the conveyance of goods from the station,
Furthermore, when a new cart that arrives at the station and can pick up a load first occurs, a transport cart system that assigns a movement command that has already been assigned to another cart to the new cart.

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