Article transport facility and article transporting method

An article transport facility in which movable bodies can merge into a merging portion while preventing collisions between the movable bodies. A communication relay device is provided to each of the first merging path, the second merging path, and the post-merging path. Each communication relay device includes an antenna portion, a relay device main body that associates movable body information obtained by communicating with the movable body communication devices using the antenna portion with identification information which indicates which one of the paths the antenna portion that received the movable body information is provided to, and that is capable of communicating the information thus obtained to the managing means. The managing means determines in which path the movable body exists to manage operations of a plurality of movable bodies based on said body information and identification information which are received from said main body.

TECHNICAL FIELD

The present invention relates to an article transport facility that comprises a travel path including at least a first path and a second path, a plurality of movable bodies which travel along the travel path for transporting articles, a communication relay device for communicating wirelessly with a movable body communication device provided to each of the plurality of movable bodies, managing means for issuing operation command information to each of the plurality of movable bodies through wireless communication between the communication relay device and the movable body communication device to manage operations of the plurality of movable bodies at a merging portion at which the first path and the second path merge with each other wherein each of the plurality of movable bodies includes travel control means for controlling travel of the movable body based on the operation command information from the managing means received by the movable body communication device.

BACKGROUND ART

In such an article transport facility, since the movable bodies may collide with each other if the movable bodies are allowed to travel from both the first path and the second path into the merging portion, the movable bodies need to be caused to travel into the merging portion while preventing a collision between the movable body that merge into the merging portion from the first path and the movable body that merges into the merging portion from the second path.

To this end, in a conventional article transport facility, a first merging detecting sensor is provided for detecting whether there is any movable body entering a first merging path that extends from the first path to the merging portion. By communicating the detected information from the first merging detecting sensor to the managing means and by communicating entering information to the managing means from the vehicle that has entered the second merging path extending from the second path to the merging portion, if the managing means determines that there are vehicles that are entering both the first merging path and the second merging path, it issues an operation command information to one of the vehicles to stop its travel to prevent a collision. (See, for example, Patent Document 1.)

In the facility described in Patent Document 1, since the entry of the movable body is detected by the first merging detecting sensor when allowing a movable body entering the first merging path to travel and merge through the first merging path into the merging portion, the managing means issues this first path entering information to the movable body that has entered the second merging path, as operation command information. The managing means continually issues this first path entering information as operation command information until after a predetermined amount time allowed for the movable bodies to complete the merging movements has elapsed. Thus, when a movable body merges into the merging portion through the first merging path, the movable bodies are prevented from colliding with each other by stopping the movable body that has entered the second merging path.

Also, when a movable body enters the second merging path, second path entering information which indicates that the movable body has entered the second merging path is communicated to the managing means. The managing means issues, as operation command information, information obtained by putting together the second path entering information and first entering presence information that indicates whether the first path entering information is detected by the first merging detecting sensor, to each of the movable bodies entering the first and second merging paths. And the managing means continually issues this operation command information obtained by putting together the second path entering information and the first entering presence information until after a predetermined amount time allowed for the movable body to complete the merging travel has elapsed. Thus, if travel controlling means of the movable body that has entered the second merging path determines that a movable body has entered the first merging path based on the first entering presence information, it causes the movable body to stop to prevent a collision between the movable bodies. And if the travel controlling means determines that no movable body has entered the first merging path based on the first entering presence information, it causes the movable body to travel and merge.

PRIOR ART DOCUMENT

Patent Documents

Patent Document 1: Japanese Patent Application Publication No. 2002-351543

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

With the facility described in the above-mentioned Patent Document 1, the managing means determines if there is any movable body that has entered the first merging path and if there is any movable body that has entered the second merging path by receiving the detected information from the first merging detecting sensor and the second path entering information from a movable body. And once the managing means issues the operation command information to cause a vehicle to perform a merging travel in which the vehicle travels through the merging portion from the first merging path or the second merging path, the managing means prevents a collision between movable bodies by not allowing next movable body to merge until after an amount of time allowed for the movable body to finish traveling through the merging portion and to complete the merging travel has elapsed.

However, that the movable body has completed the merging travel is determined based solely on the elapse of the time period; thus, if the movable body stops abnormally due to a mechanical failure etc. during the merging travel, it is determined based on the elapse of the time period that the movable body has completed the merging, and the next vehicle is caused to start a merging travel despite the fact that the movable body has not actually completed the merging travel, as a result of which a collision of the movable bodies may occur.

In addition, for example, when an operator uses a remote control device which can provide a travel command to a movable body to manually cause the movable body which had stopped abnormally to travel, there are times when the movable body which had stopped abnormally is caused to travel in the direction that is opposite from the traveling direction and to enter the merging portion from the downstream side of the merging portion with respect to the travel direction. In this case, the managing means cannot detect the movable body which was manually caused to enter the merging portion, and a collision may occur with a movable body that has been caused to perform a merging travel or with a next movable body that is caused to perform a merging travel.

There are times when the managing means is activated due to a failure or at the beginning of an operation. And if a movable body has stopped midway through the first merging path or the second merging path at the time of the activation, the managing means cannot recognize the stopped movable body; thus, the next movable body which is caused to perform a merging travel may collide with it. While this collision can be prevented by inputting information that indicates that a movable body has stopped midway through the path into the managing means, this inputting operation is burdensome.

The present invention is made in light of such issues, and an object is to provide an article transport facility in which movable bodies can be caused to merge into the merging portion while preventing the movable bodies from colliding with each other.

Means for Solving the Problems

To attain this object, an article transport facility in accordance with the present invention comprises: a travel path including at least a first path and a second path; a plurality of movable bodies which travel along the travel path for transporting articles; a communication relay device for communicating wirelessly with a movable body communication device provided to each of the plurality of movable bodies; managing means for issuing operation command information to each of the plurality of movable bodies through wireless communication between the communication relay device and the movable body communication device to manage operations of the plurality of movable bodies at a merging portion at which the first path and the second path merge with each other; wherein each of the plurality of movable bodies includes travel control means for controlling travel of the movable body based on the operation command information from the managing means received by the movable body communication device. The communication relay device is individually provided to each of a first merging path that extends from the primary path to the merging portion, a second merging path that extends from the secondary path to the merging portion, and a post-merging path that includes the merging portion and extends subsequent to merging at the merging portion. And each said communication relay device includes an antenna portion that is provided along the first merging path, the second merging path, or the post-merging path and that is capable of communicating information wirelessly with the movable body communication device, and a relay device main body to which the antenna portion is connected through a connection line and which is capable of communicating information with the managing means through a communication line. The antenna portion is a sheet-shaped antenna that is formed to be long and to have a sheet-shape and a flat plate shaped cross-section and that forms a communication enabled region over an entire surface of the antenna portion. The relay device main body is configured to associate movable body information obtained using the antenna portion through communication with the movable body communication device with identification information that indicates which one of the first merging path, the second merging path, and the post-merging path the antenna portion that received the movable body information is provided to, and to communicate information thus obtained to the managing means. And the managing means is configured to determine which one of the first merging path, the second merging path, and the post-merging path the movable body exists in, based on the movable body information and the identification information which are received from the relay device main body to control operations of the plurality of movable bodies.

An article transporting method corresponding to the above includes a travel path including at least a first path, a second path, and a merging portion at which the first path and the second path merge with each other, a plurality of movable bodies which are configured to travel along the travel path to transport articles, and each of which includes a vehicle communication device and travel control means, managing means for managing operation of each of the plurality of movable bodies in order to manage operations of the plurality of movable bodies at least at the merging portion, and a communication relay device individually provided to each of a first merging path that extends from the first path to the merging portion, a second merging path that extends from the second path to the merging portion, and a post-merging path that includes the merging portion and extends subsequent to merging at the merging portion.

Each said communication relay device includes an antenna portion that is provided along the first merging path, the second merging path, or the post-merging path and that is capable of communicating information wirelessly with the movable body communication device, and a relay device main body to which the antenna portion is connected through a connection line and which is capable of communicating information with the managing means through a communication line. The antenna portion is a sheet-shaped antenna that is formed to be long and to have a sheet-shape and a flat plate shaped cross-section and that forms a communication enabled region over an entire surface of the antenna portion. And the article transporting method comprises causing the relay device main body to associate movable body information obtained using the antenna portion through communication with the movable body communication device with identification information that indicates which one of the first merging path, the second merging path, and the post-merging path the antenna portion that received the movable body information is provided to, and to communicate information thus obtained to the managing means; causing the managing means to determine which one of the first merging path, the second merging path, and the post-merging path the movable body exists in, based on the movable body information and the identification information which are received from the relay device main body, to generate operation command information, and to issue operation command information to at least one of the plurality of movable bodies through wireless communication between the said communication relay device and the said movable body communication device; and causing the travel control means to control travel of at least one of the movable bodies based on the operation command information from the managing means received by the movable body communication device.

With such configuration or method, if a movable body exists in any of the first merging path, the second merging path, or the post-merging path, the travel control means provided to the movable body transmits movable body information (for example, information that identifies the movable body) to the communication relay device by the movable body communication device. The communication relay device can receive the movable body information from the movable body because the communication relay device is individually provided to each of the first merging path, the second merging path, and the post-merging path, and because the antenna portion which is a sheet-shaped antenna is arranged along the paths. The relay device main body of the communication relay device associates the movable body information with the identification information that indicates which one of the first merging path, the second merging path, and the post-merging path the antenna portion that received the movable body information is provided to, and communicates the movable body information and the identification information to the managing means. Thus, because the managing means receives the movable body information and the identification information from the relay device main body, it can determine in which one of the first merging path, the second merging path, and the post-merging paths the movable body exists.

Therefore, since the managing means can recognize that the movable bodies have entered both the first merging path and the second merging path, a collision between the movable bodies can be prevented by issuing operation command information for stopping the travel to one of the movable bodies. And even when a movable body was caused to start a merging travel, the managing means can determine whether a movable body exists in the path to be traveled by the movable body. Therefore, even if a movable body was manually caused to enter the post-merging path, for example, the managing means can recognize the entrance by the movable body, and can prevent a collision between the movable bodies by issuing operation command information for stopping the travel to the movable body that was caused to start the merging travel.

And even if a movable body has stopped at an intermediate location from the first path or the second path to the merging portion when the managing means is activated due to a failure or at the beginning of an operation, the travel control means provided to the vehicle can transmit movable body information to the communication relay device by means of the movable body communication device. Therefore, since the managing means can receive the movable body information and the identification information from the movable body that has stopped midway through the path, the managing means can recognize that the movable body has stopped midway through the path without having to input into the managing means any information that indicates that a movable body has stopped midway through the path. Therefore, a collision between movable bodies caused by allowing a next vehicle to perform a merging travel can be prevented in advance.

Thus, an article transport facility can be provided in which movable bodies can be caused to merged into the merging portion while preventing the movable bodies from colliding with each other.

In the embodiment of the article transport facility in accordance with the present invention, when the movable body to which the travel control means is provided enters the first merging path or the second merging path, the travel control means preferably causes the movable body communication device to transmit merging travel request information for requesting a merging travel into the merging portion from the first path or the second path to the communication relay device, wherein when the managing means receives the merging travel request information, if the managing means determines that no other movable body exists in the path to be traveled during the merging travel and that there is no movable body which was caused to start a merging travel earlier, the managing means is preferably configured to issue a merging travel command for commanding a merging travel as the operation command information to the movable body that transmitted the merging travel request information, and to issue a passage entry prohibition command for prohibiting entry into the path to be traveled to another movable body as the operation command information, wherein if the managing means determines that a movable body exists in the path to be traveled during the merging travel or that there is a movable body which was caused to start a merging travel earlier, the managing means is preferably configured to issue a merging travel prohibition command which prohibits a merging travel to the movable body that transmitted the merging travel request information as the operation command information.

The article transporting method corresponding to the above, preferably comprises causing the travel control means to generate merging travel request information for requesting a merging travel from the first path or the second path to the merging portion when the movable body to which the travel control means is provided enters the first merging path or the second merging path, and to transmit the merging travel request information to the communication relay device by the movable body communication device wherein the step of causing the managing means to issue operation command information includes: when the managing means receives the merging travel request information, if the managing means determines that no other movable body exists in the path to be traveled during the merging travel and that there is no movable body which was caused to start a merging travel earlier, causing the managing means to issue a merging travel command for commanding a merging travel as the operation command information to the movable body that transmitted the merging travel request information, and to issue a passage entry prohibition command for prohibiting entry into the path to be traveled to another movable body as said operation command information, and if the managing means determines that a movable body exists in the path to be traveled during the merging travel or that there is a movable body which was caused to start a merging travel earlier, causing the managing means to issue a merging travel prohibition command which prohibits a merging travel to the movable body that transmitted the merging travel request information as the operation command information.

With such configuration or method, if a movable body enters the first merging path or the second merging path, the managing means can recognize that the movable body entered the first merging path or the second merging path because the managing means receives the merging travel request information from the movable body. And the managing means can determine if another movable body exists in the path to be traveled during the merging travel, and if there is a vehicle that was caused to start a merging travel earlier based on whether the movable body information and the identification information have been received from another movable body. Thus, if the managing means determines that no other movable body exists in the path to be traveled during the merging travel, and that there is no vehicle that was caused to start a merging travel earlier, the managing means determines that the merging travel is possible, and issues the merging travel command to the movable body that entered the first merging path or the second merging path, and issues the passage entry prohibition command to other movable bodies to prevent a collision between the movable bodies. In addition, if the managing means determines that another movable body exists in the path to be traveled during the merging travel, and that there is a vehicle that was caused to start a merging travel earlier, it determines that the merging travel is not possible, and issues the merging travel prohibition command to the movable body that entered the first merging path or the second merging path to prevent a collision between the movable bodies.

Therefore, a collision between the movable bodies can be prevented reliably because whether the merging travel is possible can be determined at the time a movable body enters the first merging path or the second merging path without allowing a collision between the movable bodies to occur.

In the embodiment of the article transport facility in accordance with the present invention, when a movable body exists that is performing a merging travel, if the managing means determines that another movable body exists in the path to be traveled during the merging travel of the movable body, the managing means is preferably configured to issue a travel stop command for stopping travel as the operation command information to the vehicle that is performing the merging travel.

In the article transporting method corresponding to the above, the step of causing the managing means to issue operation command information preferably includes: when a movable body exists that is performing a merging travel, if the managing means determines, that another movable body exists in the path to be traveled during the merging travel of the movable body, causing the managing means to issue a travel stop command for stopping travel as the operation command information to the vehicle that is performing the merging travel.

With such configuration or method, when a movable body is performing a merging travel, the managing means can determine whether another movable body exists in the path to be traveled based on whether the movable body information and identification information have been received from another movable body. Thus, even if a movable body was manually caused to enter the path to be traveled, for example, the managing means can recognize the entrance of another movable body into the path to be traveled; thus, a collision between the movable bodies can be prevented by issuing the travel stop command to the movable body that is performing the merging travel.

In the embodiment of the article transport facility in accordance with the present invention, when the vehicle that started a merging travel earlier has not reached the merging portion, if the managing means receives the merging travel request information from a movable body that has priority to merge over the movable body that started the merging travel, the managing means is preferably configured to issue a travel stop command for stopping travel as the operation command information to the vehicle that started the merging travel earlier and to issue a merging travel command as the operation command information to the movable body that has priority to merge.

In the article transporting method corresponding to the above, the step of causing the managing means to issue operation command information includes: when the vehicle that started a merging travel earlier has not reached the merging portion, if the managing means receives the merging travel request information from a movable body that has priority to merge over the movable body that started the merging travel, causing the managing means to issue a travel stop command for stopping travel as the operation command information to the vehicle that started the merging travel earlier and to issue a merging travel command as the operation command information to the movable body that has priority to merge.

With such configuration or method, even if there is a vehicle that started a merging travel earlier, if the movable body has not reached the merging portion, the managing means issues the travel stop command to the vehicle that started the merging travel earlier to stop the vehicle, and issues the merging travel command to the movable body that has priority to merge to allow it to merge. Thus, even if there is a vehicle that started a merging travel earlier, if there is a movable body that has priority to merge over the movable body that started a merging travel earlier, the latter movable body can be given priority to merge without allowing a collision to occur between the movable bodies. Here, a priority to merge may be assigned to, for example, a vehicle that is traveling or is to travel in the first path over a movable body that is traveling or is to travel in the second path. Also, the priority to merge may be given to a movable body whose a destination is farther from the merging portion in the travel direction than the destination of a movable body that was caused to start the merging travel earlier. As a result, a plurality of movable bodies can travel efficiently, which contributes to an improvement of transporting capacity of the article transport facility while preventing a collision between the movable bodies.

In the embodiment of the article transport facility in accordance with the present invention, at least one of the first merging path, the second merging path, and the said post-merging paths is preferably divided into a plurality of divided path portions, wherein the communication relay device is preferably individually provided to each of the plurality of divided path portions, wherein the relay device main body is preferably configured to associate movable body information obtained using the antenna portion through communication with the movable body communication device with division identification information that indicates which one of the divided path portions the antenna portion that received the movable body information is provided to, and to communicate information thus obtained to the managing means, and wherein the managing means is preferably configured to determine which one of the divided path portions the movable body exists in, based on the movable body information and the division identification information which are received from the relay device main body to control operations of the plurality of movable bodies.

In the article transporting method corresponding to the above, at least one of the first merging path, the second merging path, and the said post-merging paths is preferably divided into a plurality of divided path portions, wherein the communication relay device is preferably individually provided to each of the plurality of divided path portions, wherein the step of causing the relay device main body to transmit to the managing means includes: causing the relay device main body to associate movable body information obtained using the antenna portion through communication with the movable body communication device with division identification information that indicates which one of the divided path portions the antenna portion that received the movable body information is provided to, and to communicate information thus obtained to the managing means, and wherein the step of causing the managing means to issue operation command information preferably includes: causing the managing means to determine which one of the divided path portions the movable body exists in, based on the movable body information and the division identification information which are received from the relay device main body to generate operation control information based on this determination.

With such configuration or method, because the managing means receives the movable body information and the division identification information, the managing means can determine whether a movable body exists for each divided path portion, which is a unit into which at least one of the first merging path, the second merging path, and the said post-merging paths is divided. Therefore, because the managing means can manage operations of a plurality of movable bodies such that, for example, only one movable body may be allowed to enter a divided path portion, a collision between the movable bodies can be prevented even if a number of movable bodies are allowed to enter the path or paths among the first merging path, the second merging path, and the post-merging path that is or are divided into the plurality of divided path portions. Therefore, a collision between the movable bodies can be prevented while allowing the movable bodies to be closer together when performing a merging travel, thus to perform merging travel efficiently.

In the embodiment of the article transport facility in accordance with the present invention, the managing means is preferably configured to issue an entry prohibition command for prohibiting entry into the divided path portion in which the movable body exists as the operation command information to each of the plurality of movable bodies.

In the article transporting method corresponding to the above, the step of causing the managing means to issue operation command information preferably includes causing the managing means to issue an entry prohibition command for prohibiting entry into the divided path portion in which the movable body exists as the operation command information to each of the plurality of movable bodies.

With such configuration or method, because, if a movable body exists in a divided path portion, the managing means issues an entry prohibition command to other movable bodies, a collision between the movable bodies can be reliably prevented.

In the embodiment of the article transport facility in accordance with the present invention, the travel path is preferably defined by a rail, and the antenna portion is preferably arranged along a longitudinal direction of the rail such that the antenna portion is supported by the rail.

In addition, the rail is preferably supported by a ceiling, wherein the movable body preferably includes a travel drive portion configured to travel along the rail, and the article support portion supported by the travel drive portion such that the article support portion is located below the rail, wherein the antenna portion is preferably located on a surface that faces the article support portion of the rail, and wherein a vehicle side antenna portion which communicates with the antenna portion is preferably provided to the article support portion.

BEST MODES FOR CARRYING OUT THE INVENTION

First Embodiment

Preferred embodiments of an article transport facility in accordance with the present invention are described next with reference to the drawings.

As shown inFIGS. 1 and 2, this article transport facility includes travel path S that are defined by travel rails2installed on the ceiling side such that they extend by way of or adjacent a plurality of article processors1, and two or more vehicles3(which correspond to the movable bodies) of the ceiling transportation type which can travel in one direction along the travel path S. The travel path S along which the vehicles3travel include a loop-shaped primary path4in which straight portions and curved portions are connected together, and second paths5each of which merges into or joins a straight portion of the primary path4after breaking off from the straight portion of the primary path4. And each of the first paths4and the second paths5extend by way of or adjacent the article processors1. In this article transport facility, an article6is a container for storing semiconductor substrates and the vehicles3are configured to transport articles6among the plurality of article processors1. Each travel rail2is fixedly installed to the ceiling by means of travel rail brackets7.

As shown inFIG. 2, the vehicles3has a grip portion8which suspends and grips an article6and which can be moved vertically. With the vehicle3standing still, the grip portion8can be moved by feeding out or spooling wires9(this does not have to be limited to wires, but belts, for example, can be used instead) between a raised position at which the grip portion8is positioned close to the vehicle3and a lowered position for article transfer to or from an article transfer station10installed at a location lower than the vehicle3.

Incidentally,FIG. 2shows a case where the grip portion8is lowered to the lowered position from the raised position on one side of the figure, and a case where the grip portion8is raised from the lowered position to the raised position on the other side of the figure.

The station10consists of a support platform for receiving and supporting an article6. And the station10is provided to receive from the vehicle3articles6to which a predetermined process is to be performed by the article processor1, and to deliver to the vehicle3articles6to which the predetermined process has been performed by the article processor1. A station10is located in correspondence with each of the plurality of article processors1.

The vehicle3is configured to move along the travel rail2with the grip portion8being located in the raised position, and to transfer an article6to or from the station10by raising and lowering the grip portion8between the raised position and the lowered position with the vehicle3stopped at a stop position corresponding to a transfer target station10among the plurality of stations10.

The vehicle3is configured to include a travel drive portion11which travels on the travel rail2, and an article support portion12suspended and supported by the travel drive portion11such that article support portion12is located below the travel rail2.

As shown inFIG. 3, the travel drive portion11includes a pair of driven wheels14which are driven and rotated by a drive motor13and each of which rolls on an upper surface of corresponding one of a pair of rail portions2a,2b, and a pair of guiding wheels15which can rotate freely and which are in contact with side faces of the pair of rail portions2a,2bthat face each other. And the vehicle3is configured to travel while it is guided by the travel rail2by virtue of the fact that the driven wheels14are rotated by the drive motor13and the guiding wheels15are in contact with and guided by the pair of rail portions2a,2b.

The article support portion12includes rotatable drums17which spool wires9and which are rotated by a vertical movement motor16, and a grip portion8suspended and supported by the wires9. The grip portion8includes a gripper19which can be switched by a gripper motor18between a gripping attitude in which an article6is gripped, and a grip release attitude in which the grip is released. And the rotatable drums17are rotated by the vertical movement motor16to raise and lower the grip portion8and an article6gripped thereby. And the article6is gripped and the gripping of the article6is released by switching of the gripper19by the gripper motor18.

The power receiving coil20is provided to the vehicle3such as to be located between the pair of rail portions2a,2b. Alternating current is applied to electricity supply lines21arranged along the travel rail2to generate magnetic field. And the electric power required by the vehicle3is generated by a power receiving coil20with this magnetic field; thus, the electric power is contactlessly supplied to the vehicle3. Incidentally, the electricity supply lines21are supported by the travel rail2such that they are located between the pair of rail portions2a,2b.

With regard to the travel of the plurality of vehicles3, a facility management computer which manages or controls operations of the plurality of vehicles3over the entire travel paths S is provided. And a carriage controller having travel control means22(seeFIG. 4) which controls traveling of the vehicle3based on operation command information from the facility management computer is provided to each vehicle3. The computer, control means, and managing means that are described in this specification belong to the conventional technology, and include a CPU, memory, a communication unit, etc. And algorithms for performing the functions described in the present specification are stored in the memory.

Although illustration is omitted, the vehicles3include various sensors such as a stop plate detection sensor for detecting stop plates which are installed, for example, to one side of and close to the travel rail2and which indicate a target stop position corresponding to each station10, an absolute position plate detection sensor for detecting absolute position plates which indicate the positions (distance) from a reference point of the travel path S and which are installed, for example, to one side of and close to the travel rail2, and a covered-distance sensor for detecting the distance covered by the vehicle3. The travel control means22knows or keeps track of the current position of the vehicle3on the travel path S based on detected information from the absolute position plate detection sensor and on detected information from the covered-distance sensor after detecting an absolute position, and transmits the current position information and carriage identification information such as a carriage number which can be used to identify the vehicle among the plurality of vehicles3to the facility management computer by wireless communication, etc.

The facility management computer manages or controls the operations of the plurality of vehicles3while managing each current position of a plurality of vehicles3based on the current position information from each travel control means22and the carriage identification information. The facility management computer is configured to select one vehicle3for a transporting task from among the plurality of vehicles3, and to generate a transport command, as operation command information, in which a station10is specified as a transport origin and a station10is specified as a transport destination from the plurality of stations10, for transporting an article6from the station10specified as the transport origin to the station10specified as the transport destination and to issue the transport command to the selected vehicle3. Thus, the travel control means22of the vehicle3which received the transport command controls the travel of the vehicle3to cause it to travel to the station10specified as the transport origin based on the detected information from the various sensors, and the carriage controller controls the vertical movement operation of the grip portion8and the switching operation of the grip portion8to receive an article6from the station10specified as the transport origin. Thereafter, the travel control means22controls the traveling of the vehicle3to cause it to travel to the station10specified as the transport destination based on the detected information from the various sensors. And the article6is delivered to the station10specified as the transport destination under the control of the carriage controller.

Although the operations of the vehicles3on the travel path S are basically managed or controlled by the facility management computer as described above, since at a merging portion23at which the secondary path5(which corresponds to the second path) joins or merges into the primary path4(which corresponds to the first path) as shown inFIG. 1, the vehicles3may collide with each other if the vehicles3are allowed to merge from both the primary path4and the secondary path5into the merging portion23, it is necessary to manage or control operations of the vehicles3such that the vehicles3are allowed to merge into the merging portion23while preventing a collision of vehicles3with each other. To this end, the article transport facility in accordance with the present invention includes managing means24which manages or controls operations of a plurality of vehicles3at the merging portion23and which is provided separately from the facility management computer, as shown inFIG. 4.

In order to transfer information between the managing means24and the travel control means22of each vehicle3, a communication relay device26is provided which communicates wirelessly with a vehicle communication device25(which corresponds to a movable body communication device) of each of the plurality of vehicles3. The managing means24issues operation command information to each of the plurality of vehicles3through wireless communication between the communication relay device26and the vehicle communication device25. The travel control means22provided to each of the plurality of vehicles3controls traveling of the vehicle3based on the operation command information from the managing means24and received by the vehicle communication device25. And while the vehicle is traveling in the first merging path27extending from the primary path4to the merging portion23, or the second merging path28extending from the secondary path5to the merging portion23, or the post-merging path29which contains the merging portion23subsequent to merging at the merging portion23, the travel control means22is configured to transmit movable body information (for example, carriage identification information such as a carriage number which can identify the vehicle) to the communication relay device26by means of the vehicle communication device25.

It is not that only one communication relay device26is installed or provided at the merging portion23but that a separate communication relay device26is provided to and for each of the first merging path27extending from the primary path4to the merging portion23, the second merging path28extending from the secondary path5to the merging portion23, and the post-merging path29which includes the merging portion23and extends after the merging at the merging portion23with a total of three communication relay devices26.

Each of the communication relay devices26includes an antenna portion30that is located along corresponding one of the first merging path27, the second merging path28, and the post-merging path29and that can wirelessly communicate with a vehicle communication devices25to exchange information therewith, and a relay device main body33which is connected with the antenna portion30through a communication line31and which can communicate with the managing means24to exchange information through a communication line32.

As shown inFIGS. 4 and 5, the antenna portion30is a sheet-shaped antenna that is formed to be long so as to extend along the path and to have a sheet-shape and a flat plate shaped cross-section and that forms a communication enabled region that extends in the direction of its thickness over the entire surface. Here, the term “long” means that its dimension in the width direction which is perpendicular to its longitudinal direction is substantially less than its total length in the longitudinal direction. And the total length is preferably equal to or greater than twice or more preferably five times its width. Furthermore, “flat plate shape” means that the dimension (i.e., thickness) in the thickness direction which is perpendicular to both the longitudinal direction and the width direction is substantially less than the width. And the width is preferably equal to or greater than twice the thickness and is more preferably equal to or greater than five times the thickness. As described in detail below, the antenna portion30transmits wireless signals in two dimensional directions, forms a communication enabled area which is capable of wireless communication along the surface, and outputs power with the communication enabled area along the thickness direction being formed over the entire surface. Incidentally, as the communication protocol when communicating via wireless signal, the communication is performed based on the standard telecommunications protocol (IEEE802.11a), identical to a common wireless LAN.

The antenna portion30includes a conductor portion34which is a mesh-shaped conductor, a dielectric portion35which is a sheet-shaped dielectric, and a conductor portion36which is a sheet-shaped conductor, which are laid on top of one another in that order. And a sheet-shaped insulator portion37, or38which consists of an insulator is provided on the outer surface of the mesh-shaped conductor portion34and on the back side of the sheet-shaped conductor portion36. As such, the antenna portion30is formed to have a sheet shape as a whole with the sheet-shaped insulator portion37, the mesh-shaped conductor portion34, the sheet-shaped dielectric portion35, the sheet-shaped conductor portion36, and the sheet-shaped insulator portion38being laminated and laid on top of one another in that order and bonded to each other.

As the sheet-shaped dielectric portion35, dielectric material is used that has the dielectric constant that is greater than that of the air in the frequency band or range used for signal transmission, the magnetic permeability that is approximately equal to that of the air, and the transmission speed of the electromagnetic waves that is less than that in the air. That is, because the speed of the electromagnetic waves, which are an example of a wireless signal, is determined by the product of the magnetic permeability and the dielectric constant, the speed of the electromagnetic waves that propagate within the sheet-shaped dielectric portion having the dielectric constant that is greater than that of the air and the magnetic permeability that is approximately equal to that of the air is less than the speed of the electromagnetic waves that propagate in the air. In addition, many openings39are formed in the mesh-shaped conductor portion34.

When signals corresponding to the wireless signal are applied through the connection line31, and when the antenna portion30transmits the electromagnetic waves, which are an example of the wireless signal, to the front of the sheet-shaped dielectric portion35with the magnetic field parallel to the bottom, the electromagnetic field resulting from the electromagnetic waves is formed only close to the surface of the sheet-shaped dielectric portion35. This is called an evanescent wave. The evanescent wave attenuates exponentially in the direction perpendicular to the front of the sheet-shaped dielectric portion35, and no significant electromagnetic field is formed except in proximity to the surface.

To describe in more detail, although the electromagnetic waves transmitted to the sheet-shaped dielectric portion35propagate within the sheet-shaped dielectric portion35in two dimensions, i.e. in concentric circles, the electromagnetic waves leak to the surface through the openings39of the mesh-shaped conductor portion34during the propagation. During this time, electromagnetic waves are damped exponentially in the direction perpendicular to the front of the sheet-shaped dielectric portion35, and no significant electromagnetic field is formed except in proximity to the surface. Therefore, the antenna portion30transmits wireless signals in two dimensional directions, and forms a wireless-communication enabled area along the surface.

And, as opposed to the case where the electromagnetic waves propagate in the sheet-shaped main body portion35of the antenna, when electromagnetic field is formed in the antenna portion30, electromagnetic waves in the electromagnetic field can be detected and transmitted to the relay device main body33through the connection line31.

As shown inFIG. 3, the front side of the antenna portion30is, for example, pasted on the undersurface of the rail portion2aso that the front side faces downward to form the electromagnetic field downwardly. And a vehicle side antenna portion40of the vehicle communication device25is provided on the upper surface of the article support portion12of the vehicle3at a location that faces the antenna portion30. As such, wireless communication is performed between the communication relay device26and the vehicle communication device25by exchanging electromagnetic waves between the antenna portion30and the vehicle side antenna portion40.

As shown inFIG. 4, the relay device main body33is configured to associate the movable body information (for example, carriage identification information, including the carriage number with which a vehicle can be identified) obtained using the antenna portion30through communication with the movable body communication devices25with identification information (for example, an antenna number) that indicates which one of the first merging path27, the second merging path28, and the post-merging path29the antenna portion30that received movable body information is provided to and to communicate the information to the managing means24. For example, if the movable body information is obtained by the antenna portion30provided to the first merging path27, the relay device main body33connected to the antenna portion30by the connection line31transmits the movable body information (carriage identification information) and identification information (for example, antenna identification information, including the antenna number etc.) to the managing means24through the communication line32.

The managing means24is configured to determine in which path among the first merging path27, the second merging path28, and the post-merging path29, a vehicle3exists based on the movable body information and identification information which are received from a relay device main body33to manage or control the operations of the plurality of vehicles3.

The operations of the plurality of vehicles3as they are managed or controlled by the managing means24is described next with reference to the state of the vehicle3at the merging portion23as shown inFIG. 4, and to the flow charts inFIG. 6andFIG. 7.

When the vehicle enters the first merging path27or the second merging path28, the travel control means22provided to the vehicle3temporarily stops the vehicle3and causes the vehicle communication device25to generate merging travel request information for requesting a merging travel into the merging portion23from the primary path4or the secondary path5as movable body information in addition to such information as the carriage identification information, and transmits same to the communication relay device26. At this point, since the travel control means22knows the current position of the vehicle3, it can determine from this current position whether the vehicle entered the first merging path27or the second merging path28. Also, the determination of whether the vehicle entered the first merging path27or the second merging path28, for example, may be made by allowing the vehicle communication device25and the communication relay device26to communicate with each other wirelessly.

Thus, when the vehicle3enters either the first merging path27or the second merging path28, information which includes the carriage identification information and the merging travel request information as movable body information is transmitted from the travel control means22provided to the vehicle3to the managing means24.

When the managing means24receives the merging travel request information, the managing means24can recognize whether it is the first merging path27or the second merging path28that the vehicle3entered because it receives the merging travel request information and the identification information (for example, antenna identification information, including the antenna number etc.). Thus, as shown inFIG. 3, when the merging travel request information is received, the managing means24determines whether the merging travel of the vehicle3is possible (step #1, #2).

Since if a vehicle3exists in the first merging path27, the second merging path28, or the post-merging path29, the managing means24receives the movable body information and identification information (for example, antenna identification information, including the antenna number etc.) from the vehicle3, the managing means24can determine if other vehicle3exists in the path to be traveled during the merging travel and if there is a vehicle3that was caused to start the merging travel earlier. Here, the path in which the vehicle is to travel during the merging travel consists of the first merging path27and the post-merging path29when it is the first merging path27that the vehicle3entered, and of the second merging path28and the post-merging path29when it is the second merging path28that the vehicle3entered.

If the managing means24determines that no other vehicle3exists in the path to be traveled during the merging travel and that there is no vehicle3that was caused to start the merging travel earlier, the managing means24determines that the merging travel is possible and performs a merging travel process (step #3).

Although the merging travel is determined to be possible if it is determined that no other vehicle3exists in the path to be traveled during the merging travel and there is no vehicle3that had been caused to start the merging travel earlier, the merging travel can also be determined to be possible, for example, if it is determined that no other vehicle3exists in the path to be traveled during the merging travel. Thus, a subsequent vehicle3can be allowed to enter the first merging path27or the second merging path28before a vehicle3completes its merging travel while preventing a collision with the vehicle3that was caused to start the merging travel earlier; therefore, it is possible to allow a plurality of vehicles3to merge smoothly and efficiently.

As the merging travel process, the managing means24generates a merging travel command as operation command information for allowing the merging travel and issues the command to the vehicle3which transmitted merging travel request information. This causes the travel control means22provided to the vehicle3that transmitted the merging travel request information to cause the vehicle3to start traveling and to merge. In addition, the managing means24, as the merging travel process, generates a passage entry prohibition command for preventing entry into the path to be traveled and issues it to the other vehicle3to prevent the other vehicle3from colliding with the vehicle3that is merging. This causes the travel control means22provided to the other vehicle3to extend or continue with the temporary interruption of travel after entering the first merging path27or the second merging path28, thus, preventing a collision between the vehicles3.

The managing means24determines that the merging travel is not possible if another vehicle3exists in the path to be traveled or if there is a vehicle3that was caused to start the merging travel earlier, and determines if the vehicle3that transmitted the merging travel request information is the vehicle3that should be given priority to merge (step #4). Here, for example, the vehicle3that travels in the primary path4may be given priority to merge over the vehicle3that travels in the secondary path5. Also, the vehicle whose destination station10is farther from the merging portion23in the travel direction than the destination station10of a vehicle3that was caused to start the merging travel earlier may be given priory to merge. In this case, since the managing means24needs to manage or keep track of the location of the destination station10of the vehicle3, the travel control means22transmits information including station number, etc. which indicates the destination station10as movable body information to the communication relay device26through the vehicle communication device25when the vehicle3enters the first merging path27or the second merging path28.

If the managing means24determines that the vehicle3that transmitted the merging travel request information is the vehicle3that should be given priority to merge, the managing means24determines whether it is possible to allow the vehicle3that had been determined to be given priority to merge first depending on whether the vehicle3that was caused to start the merging travel earlier has reached the merging portion23(step #5). Since the travel control means22provided to the vehicle3that was caused to start the merging travel earlier has transmitted the vehicle information to the communication relay device26through the vehicle communication device25, the managing means24knows which path the vehicle3that was caused to start the merging travel earlier exists in. Thus, the managing means24determines whether it is possible to allow the vehicle3that had been determined to be given priority to merge first if the vehicle3that was caused to start the merging travel earlier has not reached the merging portion23, or if the vehicle3that had been determined to be given priority to merge would not collide—if it is allowed to merge—with the vehicle3that was caused to start the merging travel earlier.

The priority process will be performed if the managing means24determines that priority may be given to the vehicle3(step #6). As the priority process, the managing means24generates a travel stop command for causing the vehicle3to stop traveling as operation command information, and issues it to the vehicle3which started the merging travel earlier. Thereby the travel control means22provided to the vehicle3that started the merging travel earlier causes the vehicle3to stop traveling. In addition, as the priority process, the managing means24generates a merging travel command as operation command information, and issues it to the vehicle3that was given priority to merge. Thereby the travel control means22provided to the vehicle3vehicle3that was given priority to merge causes the vehicle3to start traveling and to merge. Thus, when there is a vehicle that was caused to start the merging travel earlier, and if there is a vehicle3that has priority over such vehicle to merge enters the first merging path27or the second merging path28, the vehicle that was caused to start the merging travel earlier is stopped so that the vehicle3that has the priority can merge provided that a collision between the vehicles3can be prevented.

If the merging travel is determined to be not possible in step #2, the managing means24performs the travel stop process (step #7) if the vehicle3that transmitted the merging travel request information is not the vehicle3that was given priority to merge in step #4or if it is determined that the priority can not be given in Step5. As the travel stop process, the managing means24generates a merging travel prohibition command for prohibiting a merging travel as operation command information, and issues it to the vehicle3that transmitted the merging travel request information. Thereby, the travel control means22provided to the vehicle3that transmitted the merging travel request information keeps the vehicle3from traveling, thus preventing the collision between the vehicles3.

And, as shown in the flow chart inFIG. 7, the managing means24monitors whether any vehicle3exists in the path to be traveled by the vehicle3which was caused to start a merging travel (step #11). If any other vehicle3exists in the path to be traveled, the managing means24knows which path the vehicle3exists in based on the movable body information and the identification information (antenna identification information) because the travel control means22provided to the vehicle3transmits the movable body information to the communication relay device26by the vehicle communication device25. Thus, the managing means24can determine whether any other vehicle3exists in the path to be traveled by the vehicle3which was caused to start a merging travel.

If the managing means24determines that a vehicle3exists in the path to be traveled, it performs the travel stop process in which it generates a travel stop command for causing the vehicle3to stop traveling as operation command information, and issues it to the vehicle3which was caused to start a merging travel (step #12). If the managing means24determines that no vehicle3exists in the path to be traveled, it performs a continued travel process in which it issues a continued travel command for causing the vehicle3to continue traveling as operation command information to the vehicle3which was caused to start a merging travel (step #13). In this manner, the managing means24monitors whether a vehicle3exists in the path to be traveled until it determines that the merging travel was completed by virtue of the fact that the managing means24stops receiving the movable body information from the vehicle3which was caused to start a merging travel because the vehicle has completed traveling in the post-merging path29, and the managing means24performs either the travel stop process or the continued travel process (step #14). When a vehicle3was caused to start a merging travel and is performing the merging travel, even if a vehicle3was caused to enter the path to be traveled, for example, manually, the vehicle3is stopped, thus preventing a collision between the vehicles.

When the managing means24stops the vehicle3which was caused to start a merging travel because a vehicle3exists in the path to be traveled, the managing means24can allow the vehicle3to complete traveling though the post-merging path29by generating and issuing operation command information for causing the vehicle3to complete traveling through the post-merging path29to the vehicle3which exists in the path to be traveled. In this manner, the managing means24then determines that no vehicle3exists in the path to be traveled and performs the continued travel process to the vehicle3which was caused to stop to restart the merging travel.

Second Embodiment

Because this second embodiment is an alternative embodiment for the installation locations of the communication relay devices26of the first embodiment, and because other configurations are identical to those in the first embodiment, only the different aspects of the configuration will be described.

As shown inFIG. 8, in this second embodiment, each of the first merging path27, the second merging path28, and the post-merging path29is divided into a plurality of divided path portions41. And the communication relay device26is individually provided to each of the divided path portions41.

The relay device main body33is configured to associate the movable body information obtained using the antenna portion30through communication with the vehicle communication device25with division identification information (for example, a division number of the divided path portion) that indicates which one of the divided path portions41the antenna portion30that received the movable body information is provided to and to communicate the information to the managing means24.

Thereby, the managing means24is configured to determine which one of the plurality of divided path portions41the vehicle3exists in based on the movable body information and the division identification information (for example, division number of the divided path portion) received from the relay device main body33, and to generate the operation command information based on this determination to manage or control operations of the plurality of vehicles3.

Because, if a vehicle3is located in any of the plurality of divided path portions41, the travel control means22provided to the vehicle3transmits the movable body information to the communication relay device26through the vehicle communication device25, the relay device main body33of the communication relay device26transmits the movable body information and the division identification information (for example, division number of the divided path portion) to the managing means24. Since the managing means24is capable of recognizing which one of the plurality of divided path portions41a vehicle3exists in, the managing means24can prevent collisions between the vehicles3by generating entry prohibition command information which prohibits entry into the divided path portion41in which a vehicle3exists as operation command information, and by issuing it to each of the vehicles3even if two or more vehicles3are caused to enter each of the first merging path27, the second merging path28, and the post-merging path29. This makes it possible to allow a plurality of vehicles3to perform a merging travel while allowing the vehicles3to be closer together; thus, a plurality of vehicles3can be allowed to perform the merging travel efficiently.

The operations shown in the flow chart shown inFIG. 9may be performed in lieu of the operations, for example, as shown in the flow chart inFIG. 7in the first embodiment in which whether the vehicle3exists in the path to be traveled by the vehicle3which was caused to merge is monitored.

If the managing means24determines that there is a divided path portion41in which a vehicle3exists, it performs an entry prohibition process in which the managing means24generates an entry prohibition command information which prohibits entry into the divided path portion41as operation command information, and issues it to the vehicle3which was caused to start a merging travel (steps #21, and #22). If the managing means24determines that there is no divided path portion41in which a vehicle3exists, it performs a continued travel process in which it generates a continued travel command for causing the vehicle3to continue traveling as operation command information to the vehicle3which was caused to start the merging travel (step #23).

When a vehicle3enters the first merging path27or the second merging path28, and even if there is a vehicle that was caused to start the merging travel earlier, the travel control means24may generate, as operation command information, a passed entry permission command which permits entry into the divided path portion41which the vehicle3has already passed, and may issue it to the vehicle3that entered the first merging path27or the second merging path28. Thus, the vehicle3that is to merge next can be allowed to enter the first merging path27or the second merging path28before the vehicle3that was caused to merge earlier completes the merging travel; thus, a plurality of vehicles3may be allowed to merge efficiently and smoothly.

Alternative Embodiments

(1) Although examples in which the article transport facility in accordance with the present invention is applied to the facility having vehicles3of the ceiling transporting type were disclosed in the first and second embodiments described above, the application of the facility is not limited to this and the facility may be applied to a facility having vehicles that travel on the ground.

(2) Although, the first merging path27, the second merging path28, and the post-merging paths29are all divided into a plurality of divided path portions41in the second embodiment described above, only the first merging path27and the second merging path28, for example, may be divided into a plurality of divided path portions41. What is preferable is to have at least one of the first merging path27, the second merging path28, and the post-merging paths29divided into a plurality of divided path portions41.

INDUSTRIAL APPLICABILITY

The article transport facility may be used as a facility in which articles are transported in a warehouse, or a processing facility, etc.

DESCRIPTION OF THE REFERENCE NUMERALS AND SYMBOLS