Conveyance system and conveyance method

Abstract

[Problem] To provide a conveyance system and a conveyance method capable of appropriately controlling movement of a movable shelf. [Solution] This conveyance system comprises: a conveyance vehicle that conveys an article; and a storage device that transfers the article. The conveyance vehicle is provided with a first communication device that communicates with the storage device. The storage device is provided with a second communication device that communicates with the first communication device, and a movable shelf that stores the article. The movable shelf is movable between a transfer position to which the article is transferred by the conveyance vehicle and a retreat position retreated from the transfer position. By means of the first communication device, the conveyance vehicle transmits, to the second communication device, a determination signal indicating whether to permit the movement of the movable shelf. The storage device moves the movable shelf to the transfer position or the retreat position only when the determination signal which is obtained by means of the second communication device indicates that the movement of the movable shelf is permitted.

Description

Transport system and transport method

[0001] The present invention relates to a transport system and a transport method.

[0002] A transport system including a transport vehicle that transports items and a storage device to which the items are transferred by the transport vehicle is known (see, for example, Patent Document 1). The storage device includes, for example, a movable shelf that moves between a transfer position advanced to an area directly below a rail and a retracted position retreated from the area. The transport vehicle advances the movable shelf to the transfer position while transmitting and receiving information with the storage device via wireless communication, and performs item transfer operations such as unloading and grabbing between the movable shelf advanced to the transfer position.

[0003] JP 2023-119730 A

[0004] In a transport system, it is required that the transport vehicle and the storage device communicate with each other to send and receive information and appropriately control the movement of the movable shelves. For example, it is necessary to appropriately control the movable shelves so that they do not return from the transfer position to the retracted position during transfer. However, Patent Document 1 does not specifically disclose how to control the movable shelves.

[0005] An object of the present invention is to provide a transport system and a transport method that can appropriately control the movement of a movable shelf.

[0006] A conveying system according to one aspect of the present invention is a conveying system comprising a conveying vehicle that conveys goods and a storage device to which the goods are transferred by the conveying vehicle, wherein the conveying vehicle is provided with a first communication device that communicates with the storage device to transfer the goods, the storage device is provided with a second communication device that communicates with the first communication device, and a movable shelf that stores the goods, the movable shelf is movable between a transfer position to which the goods are transferred by the conveying vehicle and a retracted position to which the movable shelf is retracted from the transfer position, the conveying vehicle transmits a determination signal indicating whether or not to permit movement of the movable shelf to the second communication device via the first communication device, and the storage device moves the movable shelf to the transfer position or the retracted position only if the determination signal obtained via the second communication device indicates that movement of the movable shelf is permitted.

[0007] A transport method according to one aspect of the present invention is a transport method for a transport system including a transport vehicle that transports items and a storage device to which the items are transferred by the transport vehicle, wherein the transport vehicle and the storage device are capable of sending and receiving information to each other via wireless communication, and the storage device is equipped with movable shelves for storing items, and the transport vehicle transmits a determination signal indicating whether or not movement of the movable shelves is permitted to a second communication device via a first communication device, and the storage device moves the movable shelves to a transfer position or a retreat position only if the determination signal acquired via the second communication device indicates permission to move the movable shelves.

[0008] The transport system according to an aspect of the present invention can appropriately control the movement of the movable shelves by transmitting a determination signal from the transport vehicle to the storage device indicating whether the transport vehicle is permitted to move the movable shelves.

[0009] According to the conveying system and conveying method of the above aspect, the storage device may move the movable shelf to a retracted position only when the determination signal indicates that movement of the movable shelf is permitted when the movable shelf is located at a transfer position.

[0010] According to the transport system and transport method of the above aspects, the transport vehicle sets the signal state of the determination signal to either a permitted state indicating that movement of the movable shelf is permitted or a prohibited state indicating that movement of the movable shelf is prohibited, and when the transport vehicle grasps an item placed on the movable shelf, the transport vehicle may change the signal state of the determination signal from the permitted state to the prohibited state when it confirms that the movable shelf on which the item to be grasped is placed has moved from the retracted position to the transfer position, and when it grasps the item and confirms that the item to be grasped is not present on the movable shelf at the transfer position, it may change the signal state of the determination signal from the prohibited state to the permitted state. With this configuration, it is possible to appropriately control the movement of the movable shelf when the transport vehicle receives an item from the movable shelf.

[0011] According to the transport system and transport method of the above aspects, when the transport vehicle grasps an item placed on the movable shelf, it may change the signal state of the determination signal from the prohibition state to the permission state when it confirms that the item to be grasped is present on the movable shelf, grasp the item, and then change the signal state of the determination signal from the permission state to the prohibition state while the movable shelf is being moved from the transfer position to the retracted position or when the movement is completed. With this configuration, it is possible to appropriately control the movement of the movable shelf when the transport vehicle receives an item from the movable shelf.

[0012] According to the transport system and transport method of the above aspects, the transport vehicle sets the signal state of the determination signal to either a permitted state indicating that movement of the movable shelf is permitted or a prohibited state indicating that movement of the movable shelf is prohibited, and when unloading an item onto the movable shelf, the transport vehicle may change the signal state of the determination signal from the permitted state to the prohibited state upon confirming that the movable shelf has moved from the retracted position to the transfer position, and may unload an item onto the movable shelf at the transfer position and change the state of the determination signal from the prohibited state to the permitted state upon confirming that the item is present on the movable shelf. With this configuration, it is possible to appropriately control the movement of the movable shelf when the transport vehicle delivers an item to the movable shelf.

[0013] According to the transport system and transport method of the above aspects, when the transport vehicle unloads an item, if it confirms that there is no item on the movable shelf at the unloading destination, it may change the signal state of the determination signal from the prohibition state to the permission state, and after unloading of the item onto the movable shelf is completed, if it confirms that the movable shelf has moved from the transfer position to the retracted position, it may change the signal state of the determination signal from the permission state to the prohibition state. With this configuration, it is possible to appropriately control the movement of the movable shelf when the transport vehicle delivers an item to the movable shelf.

[0014] According to the transport system and transport method of the above aspects, the transport vehicle may check whether an item is present on the movable shelf while maintaining the signal state of the determination signal transmitted from the first communication device to the second communication device in a prohibited state. With this configuration, it is possible to check whether an item is present on the movable shelf without moving the movable shelf. Furthermore, according to the transport system and transport method of the above aspects, the storage device may be equipped with multiple movable shelves, and may move a specific movable shelf when the determination signal indicates permission to move the movable shelf and identification information of the specific movable shelf to be moved is acquired via the first communication device, and may not move the specific movable shelf when the determination signal indicates prohibition of movement of the movable shelf and identification information is acquired via the first communication device.

[0015] FIG. 1 is a diagram showing a schematic configuration of a conveying system according to the present embodiment; FIG. 2 is a diagram showing a schematic configuration of a conveying vehicle according to the present embodiment; FIG. 3 is a diagram showing a storage device according to the present embodiment as viewed from the Y direction; FIG. 4 is a diagram showing a storage device according to the present embodiment as viewed from the X direction; FIG. 5 is a diagram showing changes in the signal states of conveying information and storage information during a cargo grabbing operation according to the present embodiment; FIG. 6 is a diagram showing changes in the signal states of conveying information and storage information during an unloading operation according to the present embodiment; FIG. 7 is a diagram showing changes in the signal states of conveying information and storage information during a check function according to the present embodiment.

[0016] The present invention will be described below through embodiments, but the following embodiments do not limit the scope of the invention. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention. In the drawings, identical or similar parts may be designated by the same reference numerals, and redundant explanations may be omitted. Furthermore, the shapes and sizes of elements in the drawings may be exaggerated for clarity.

[0017] The positions and orientations of components may be described with reference to an XYZ Cartesian coordinate system, in which the X and Y directions are horizontal and the Z direction is vertical.

[0018] Fig. 1 is a diagram showing a schematic configuration of a transport system HS according to this embodiment. Fig. 2 is a diagram showing a schematic configuration of a transport vehicle 10 according to this embodiment. The transport system HS transfers the article 100 between the transport vehicle 10 that transports the article 100 and a placement section on which the article 100 can be placed.

[0019] As shown in FIG. 1 , the transport system HS includes, for example, a transport vehicle 10 , a first communication device 20 , a second communication device 30 , and a storage device 40 .

[0020] The transport vehicle 10 is a transport vehicle that transports the article 100, and travels along a ceiling track R that is set at a position higher than the floor, such as the ceiling of a clean room. The ceiling track R is suspended via supports BR that are fixed to the ceiling. The following description will be given taking as an example a case where the transport vehicle 10 is a ceiling transport vehicle. However, the transport vehicle 10 is not limited to a ceiling transport vehicle, and may be any transport vehicle that transports the article 100 and transfers the article 100.

[0021] The transport vehicle 10 transports the article 100 in a suspended state within the storage space AS. The transport vehicle 10 is used, for example, to transport the article 100 between a processing device and a storage device 40. The X direction in Fig. 2 is the traveling direction of the transport vehicle 10. The Z direction in Fig. 2 is the vertical direction of the transport vehicle 10.

[0022] The processing equipment is, for example, a film forming equipment, a coater / developer, an exposure equipment, an etching equipment, etc., and performs various processes in the process of manufacturing a device (e.g., a semiconductor device). The container storage device is, for example, disposed on a transport path for transporting the article 100, and temporarily stores the article 100. The container storage device is, for example, disposed near the ceiling. The article 100 stores, for example, wafers or reticles used in manufacturing semiconductor elements. The article 100 is, for example, a FOUP (Front Opening Unified Pod), a SMIF pod, or a reticle pod, the interior of which can be purged. The article 100 is an example of the "article" of the present invention.

[0023] As shown in FIG. 2, the transport vehicle 10 includes, for example, a traveling section 2, a connecting section 3a, a support section 3b, a power receiving device 4, a main body section 5, a cover 6, and a vehicle control device 7.

[0024] The travel unit 2 causes the transport vehicle 10 to travel along the overhead track R. The travel unit 2 includes, for example, wheels arranged to contact the overhead track R and a travel drive unit that drives the wheels. The travel drive unit generates a driving force for traveling the transport vehicle 10. The travel drive unit has, for example, a travel motor such as a linear motor or a rotary motor. The travel drive unit also has a rotary encoder or a linear encoder. The travel drive unit controls the linear motor or rotary motor based on the detection results such as the number of rotations of the wheels detected by the rotary encoder or linear encoder, and adjusts the speed or stopping position of the transport vehicle 10.

[0025] The connecting portion 3 a connects the running portion 2 and the support portion 3 b. For example, one end of the connecting portion 3 a is connected to the running portion 2, and the other end is connected to the support portion 3 b. The support portion 3 b is disposed along a horizontal plane and supports the main body portion 5.

[0026] The power receiving device 4 receives power contactlessly from the contactless power feeding facility. The power receiving device 4 is provided, for example, on the connecting portion 3a. The method of contactless power feeding from the contactless power feeding facility to the power receiving device 4 can be any of the following: electromagnetic induction, magnetic field (electric field) resonance, electric field coupling, and electromagnetic wave. The power received by the power receiving device 4 is converted into DC power and supplied to the traveling drive unit and the main body unit 5.

[0027] The main body 5 is connected to the running unit 2 via the connecting unit 3a, and moves along the ceiling track R together with the running unit 2. The main body 5 includes, for example, a lateral extension unit 11, a rotation mechanism 12, a lifting unit 13, and a holding unit 14.

[0028] The lateral extension unit 11 extends the rotation mechanism 12, the lifting unit 13, and the holding unit 14 laterally relative to the traveling direction. The traveling direction of the main body unit 5 is the direction in which the transport vehicle 10 travels along the ceiling track R by the traveling unit 2, i.e., the ±X direction. The side of the traveling direction is the direction perpendicular to the traveling direction, i.e., the ±Y direction. The rotation mechanism 12 rotates the lifting unit 13 within a horizontal plane.

[0029] The lifting unit 13 lowers or raises the holding unit 14 at a predetermined speed and holds the holding unit 14 at a target height. The lifting unit 13 is attached, for example, below the rotation mechanism 12. The holding unit 14 is suspended from the lifting unit 13 by a plurality of suspension members. The lifting unit 13 is, for example, a hoist, and lowers the holding unit 14 by letting out the plurality of suspension members. The lifting unit 13 also raises the holding unit 14 by winding up the plurality of suspension members.

[0030] The holding unit 14 holds the item 100. The holding unit 14 holds the item 100 in a suspended state by, for example, gripping a flange of the item 100. The method by which the holding unit 14 grips the item 100 is not particularly limited, and the holding unit 14 may grip the item 100 from above or by pinching it from the left and right. The holding unit 14 is, for example, a chuck equipped with multiple claws that can move horizontally. The holding unit 14 moves the claws below the flange by a driving force such as a motor. Then, the lifting unit 13 lifts up the hanging member, causing the holding unit 14 to rise, thereby holding the item 100 in a suspended state.

[0031] Covers 6 are provided on the ±Y sides of the main body 5, and each cover 6 is fixed to a support 3b and extends from the support 3b in the −Z direction. The pair of covers 6 form a space in which the item 100 is stored, i.e., a storage space AS.

[0032] The vehicle control device 7 may include a processor such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit) and a non-volatile or volatile semiconductor memory (e.g., RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), or EEPROM (Electrically Erasable Programmable Read Only Memory)). For example, the vehicle control device 7 may be a microcontroller such as an MCU.

[0033] The vehicle control device 7 controls various operations of the transport vehicle 10. The vehicle control device 7 controls the travel of the transport vehicle 10 by controlling the travel drive unit. The vehicle control device 7 controls the transfer of the items 100 to and from the storage device 40. The transfer of the items 100 includes either or both of unloading the items 100 from the storage device 40 and grabbing the items 100 from the storage device 40.

[0034] The vehicle control device 7 controls a drive unit (e.g., an electric motor) provided in the lateral discharge unit 11, thereby controlling the lateral discharge operation of the lateral discharge unit 11. The vehicle control device 7 controls the lifting unit 13 to control the winding and unwinding (lowering) of the hanging member, thereby controlling the position of the holding unit 14. The vehicle control device 7 also controls the operation of the holding unit 14, causing the holding unit 14 to hold the article 100, or releasing the holding of the article 100 by the holding unit 14.

[0035] When transferring the item 100, wireless communication is performed between the transport vehicle 10 and the storage device 40. The communication standard for the wireless communication is not particularly limited. An example of wireless communication is interlock communication. Interlock communication is communication in which the operation and status of the transport vehicle 10 and the storage device 40 are confirmed and notified to each other in order to properly transfer the item 100. The vehicle control device 7 is connected to the first communication device 20, and performs interlock communication with the storage device 40 via the first communication device 20.

[0036] The first communication device 20 is provided in the transport vehicle 10. The first communication device 20 is electrically connected to the vehicle control device 7. The first communication device 20 communicates with the second communication device 30, and transmits and receives information to and from the second communication device 30.

[0037] Fig. 3 is a view of the storage device 40 according to this embodiment as seen from the Y direction (left-right direction). Fig. 4 is a view of the storage device 40 according to this embodiment as seen from the X direction (travel direction).

[0038] The storage device 40 stores the item 100. The storage device 40 is, for example, a buffer in which the item 100 is temporarily stored. For example, when the item 100 being transported by the transport vehicle 10 cannot be transferred to the target delivery port because another item 100 is loaded at the target delivery port, the item 100 is temporarily stored in the storage device 40. The delivery port is a loading section for transferring the item 100 to a semiconductor processing device (not shown), such as a cleaning device, a film forming device, a lithography device, an etching device, a heat treatment device, or a planarization device.

[0039] The storage device 40 includes a plurality of shelves 50, a detection unit 45, and a storage control device 70.

[0040] The shelves 50 are arranged in a vertical line. Each shelf 50 has a plurality of mounting sections 60. When viewed from the travel direction, the shelves 50 are arranged on both sides of the ceiling track R, sandwiching the travel area, as shown in FIG. 4. In other words, the shelves 50 are arranged on both the left side (-Y side) and the right side (+Y side) of the travel area.

[0041] The placement section 60 is arranged along the travel direction on each shelf 50. The placement section 60 is a portion on which one article 100 is placed. In other words, the placement section 60 is a portion that supports and holds one article 100 from below. In the example shown in Figures 3 and 4, the placement section 60 is a portion on the shelf 50 on which one article 100 is placed. A positioning member that positions the article 100 may be arranged on the upper surface of the placement section 60. Furthermore, the placement section 60 is formed, for example, to be the same size as the article 100 or larger than the article 100 in a plan view.

[0042] In the following description, a unit of a group of mounting sections 60 arranged in a vertical line is defined as a "row," and a group of mounting sections 60 in one row may be collectively referred to as a shelf row. When viewed from the travel direction, the storage device 40 has multiple shelf rows arranged along a direction perpendicular to the vertical direction (travel direction) on both the left side (-Y side) and the right side (+Y side) of the travel area. Note that, to distinguish between the multiple shelf rows, they may be referred to as the first row, second row, third row, and fourth row in the +X direction.

[0043] The storage device 40 illustrated in Figures 3 and 4 has eight shelves 50 on both the left (-Y side) and right (+Y side) sides of the travel area. Each shelf 50 has four mounting sections 60. In other words, the storage device 40 has four rows of shelves arranged on each side along the travel direction. In each row illustrated in Figures 3 and 4, eight mounting sections 60 are arranged in the vertical direction.

[0044] 3 and 4, only the top shelf 50 of the eight shelves 50 is suspended from the ceiling, and the other shelves 50 are installed integrally on the floor. The top shelf 50 may be referred to as the "first storage section," and the shelves 50 other than the top shelf 50 may be collectively referred to as the "second storage section."

[0045] The first storage section is suspended from the ceiling by suspension parts 41. Specifically, when viewed from the running direction, the top shelf 50, which is an example of the first storage section, is suspended from the ceiling on both sides of the running area. The top shelf 50 is fixed to the suspension parts 41 on both sides of the running area and is immovable relative to the suspension parts 41. The suspension parts 41 are suspended from the ceiling C via attachment parts 42. The suspension parts 41 are arranged, for example, at equal intervals along the extension direction of the ceiling track R.

[0046] The top shelf 50, which is the first storage section, is provided with a fall prevention fence 43. The fall prevention fence 43 prevents the article 100 from falling from the loading section 60. The fall prevention fences 43 are arranged on the left and right of the article 100 loaded on the loading section 60, for example, when viewed from the direction of travel. The fall prevention fences 43 extend along the ceiling track R.

[0047] When transferring (unloading or grabbing) an item 100 onto the top shelf 50, the transport vehicle 10 uses the horizontal output unit 11 to laterally output the lifting unit 13 and the holding unit 14 in the +Y direction or the -Y direction, and the lifting unit 13 raises and lowers the holding unit 14. The transport vehicle 10 then controls the operation of the holding unit 14 to unload the item 100 onto the placement unit 60 specified by a higher-level controller, or to grab the item 100 placed on the placement unit 60.

[0048] The second storage section is disposed below the first storage section and is installed on the floor. When viewed from the travel direction, the second storage sections are disposed on both sides of the travel area and are arranged in pairs so as to face each other across the lifting area S of the holding section 14. The lifting area S is an area where the holding section 14 lifts and lowers when transferring the item 100 to the second storage section.

[0049] Here, each shelf 50 in the second storage section is a movable shelf that can be moved to a transfer position where the item 100 can be transferred. Specifically, each shelf 50 can be moved between a transfer position where the item 100 is transferred by the transport vehicle 10 and a retracted position where the shelf 50 is retracted from the transfer position. The transfer position is set within the lifting area S.

[0050] Specifically, all shelves 50 shown in Fig. 4 are located in the retracted position. In Fig. 4, the multiple shelves 50 arranged on the left side can be moved to a transfer position within the lifting area S by sliding each shelf independently in the right direction (+Y direction). Also, in Fig. 4, the multiple shelves 50 arranged on the right side can be moved to a transfer position within the lifting area S by sliding each shelf independently in the left direction (-Y direction).

[0051] 3 and 4, one transport vehicle 10 is assigned to transfer the item 100. That is, the transfer of the item 100 in the storage device 40 is not performed simultaneously by multiple transport vehicles 10, but by one transport vehicle 10. The drive source for the movement of each shelf is, for example, a motor, a cylinder, or the like, and is controlled by the storage control device 70.

[0052] Transfer from the transport vehicle 10 to the second storage section is performed by raising and lowering the holding section 14 relative to the placement section 60 of the shelf 50 that has advanced to the transfer position (lifting area S). In this embodiment, for the purpose of distinguishing between the second storage sections, the shelves 50 on the left side are referred to as shelf 50-1, shelf 50-2, shelf 50-3, shelf 50-4, shelf 50-5, shelf 50-6, and shelf 50-7 from bottom to top, and the shelves 50 on the right side are referred to as shelf 50-8, shelf 50-9, shelf 50-10, shelf 50-11, shelf 50-12, shelf 50-13, and shelf 50-14 from bottom to top.

[0053] The detection unit 45 detects the presence or absence of an article 100 placed on the placement unit 60. As an example, the detection unit 45 detects the presence or absence of an article 100 placed on each placement unit 60. The detection unit 45 is connected to the storage control device 70 and transmits the detection result to the storage control device 70. The detection unit 45 is equipped with, for example, either a placement sensor or a presence sensor, or both, for each placement unit 60. When an article 100 is placed on a placement unit 60, the detection results of the placement sensor and the presence sensor of that placement unit 60 are both ON.

[0054] The second communication device 30 is capable of communicating with the first communication device 20. The second communication device 30 receives transport information from the first communication device 20 through interlock communication. That is, the transport vehicle 10 transmits transport information to the second communication device 30 via the first communication device 20. The storage device 40 receives the transport information transmitted from the transport vehicle 10 via the second communication device 30.

[0055] Furthermore, the second communication device 30 transmits storage information to the first communication device 20 in interlock communication. That is, the storage device 40 transmits the storage information to the first communication device 20 via the second communication device 30. The transport vehicle 10 receives the storage information transmitted from the storage device 40 via the first communication device 20. The first communication device 20 and the second communication device 30 are, for example, optical communication devices that perform optical communication and perform serial communication.

[0056] The carried information includes a Valid_A signal, a determination signal (Permission), and an RTN (Requested Table Number) signal. The Valid_A signal is a signal indicating that the first communication device 20 is in communication. When the Valid_A signal is a Hi-level signal, it indicates that the first communication device 20 is in communication, and when the Valid_A signal is a Lo-level signal, it indicates that the first communication device 20 is not in communication. Note that when the signal is Hi-level, it is sometimes referred to as "ON", and when the signal is Lo-level, it is sometimes referred to as "OFF".

[0057] The determination signal is a signal that indicates whether or not movement of the shelf 50 is permitted. The signal state of the determination signal is set to either an permitted state that indicates that movement of the shelf 50 is permitted, or a prohibited state that indicates that movement of the shelf 50 is prohibited. The permitted state is, for example, when the signal state of the determination signal is at a Hi level. The prohibited state is, for example, when the signal state of the determination signal is at a Lo level. In other words, when the determination signal is "ON", movement of the shelf 50 is permitted, and when the determination signal is "OFF", movement of the shelf 50 is prohibited. Prohibited movement of the shelf 50 includes both or either movement from the retracted position to the transfer position and movement from the transfer position to the retracted position.

[0058] The RTN signal is a signal that indicates the identification information of the shelf 50 to which the transport vehicle 10 wishes to transfer (hereinafter referred to as "destination shelf information"). In other words, the destination shelf information is the identification information of the specific movable shelf to which the transport vehicle 10 is to move. The RTN signal includes RTN1 to RTN6 signals, and the destination shelf information is indicated by the on / off states of these RTN1 to RTN6 signals. In other words, the destination shelf information is expressed, for example, as a six-digit binary number.

[0059] The stored information includes a Valid_P signal, an ATN signal, and a CarrierDetect signal. The Valid_P signal is a signal indicating whether the second communication device 30 is in communication. When the Valid_P signal is ON, it indicates that the second communication device 30 is in communication, and when the Valid_P signal is OFF, it indicates that the second communication device 30 is not in communication.

[0060] The ATN signal is a signal that indicates the identification number (hereinafter referred to as "movable shelf information") of the shelf 50 present at the transfer position. The ATN signal includes ATN1 signal to ATN6 signal, and these ATN1 signal to ATN6 signal specify the movable shelf information expressed in six-digit binary notation.

[0061] The CarrierDetect signal is a signal that indicates the presence or absence of an item 100 on the shelf 50 of the mobile shelf information indicated by the ATN signal. The CarrierDetect signal is ON if the item 100 is on the shelf 50 indicated by the mobile shelf information, and is OFF if the item 100 is not on the shelf 50 indicated by the mobile shelf information. The CarrierDetect signal is, for example, 1-bit information that indicates the presence or absence of an item 100 detected by the detection unit 45.

[0062] The second communication devices 30 are provided on the overhead track R. There is a one-to-one correspondence between the second communication devices 30 and the trains. In the example shown in Figures 3 and 4, the storage device 40 has four trains along the running direction. Therefore, four second communication devices 30 are provided on the overhead track R.

[0063] Here, a stop position T of the transport vehicle 10 is set corresponding to each of the multiple trains. This stop position T is a stop position on the overhead track R for transferring the article 100 to one of the multiple placement units 60 in one train. In the example shown in Figures 3 and 4, four stop positions T1 to T4 are set. The second communication devices 30 are provided on the overhead track R in one-to-one correspondence with each of the multiple stop positions T1 to T4. For example, the second communication devices 30 are provided near each of the multiple stop positions on the overhead track R. Note that, in order to distinguish each of the multiple second communication devices 30, they may be referred to as second communication device 30a, second communication device 30b, second communication device 30c, and second communication device 30d in the +X direction.

[0064] When the transport vehicle 10 stops at one of the plurality of stop positions T1 to T4, it performs predetermined communication with the second communication device 30 corresponding to the stop position where the transport vehicle 10 has stopped. That is, the first communication device 20 performs interlock communication only with the second communication device 30, among the plurality of second communication devices 30, that is provided corresponding to the stop position where the transport vehicle 10 has stopped. For example, the second communication device 30 provided corresponding to the stop position where the transport vehicle 10 has stopped may be the second communication device 30 that is closest to that stop position. For example, the second communication device 30 provided corresponding to the stop position where the transport vehicle 10 has stopped is mounted in a position that allows infrared communication with the first communication device 20 mounted on the transport vehicle 10 when the transport vehicle 10 has stopped at that stop position.

[0065] The first communication device 20 performs interlock communication only with the second communication device 30, among the plurality of second communication devices 30, that is provided corresponding to the stop position where the transport vehicle 10 has stopped. For example, in Fig. 3, when the transport vehicle 10 has stopped at stop position T1, the first communication device 20 performs interlock communication only with the second communication device 30a.

[0066] The storage control device 70 may include a processor such as a CPU or an MPU and non-volatile or volatile semiconductor memory (e.g., RAM, ROM, flash memory, EPROM, EEPROM). For example, the storage control device 70 may be a microcontroller such as an MCU.

[0067] The storage control device 70 is connected by wire or wirelessly to each of the multiple second communication devices 30. Furthermore, the storage control device 70 constantly transmits storage information from the second communication device 30 to the first communication device 20 in interlock communication. The storage control device 70 constantly acquires transportation information from the first communication device 20 via any one of the second communication devices 30 in interlock communication.

[0068] The storage control device 70 can move each shelf 50 to a transfer position where the item 100 can be transferred. The transport vehicle 10 transmits transport information to the second communication device 30 via the first communication device 20 in interlock communication. The storage control device 70 acquires transport information in interlock communication from the second communication device 30 corresponding to the stopping position where the transport vehicle 10 has stopped. The storage control device 70 moves the shelf 50 indicated by the transfer destination shelf information specified by the RTN signal in the transport information, i.e., the transfer destination shelf 50, from the retracted position to the transfer position.

[0069] The storage control device 70 has information on which of the multiple shelves 50 has advanced to a transfer position. The storage control device 70 also has information on at which stopping position the transport vehicle 10 is stopped. For example, the storage control device 70 is always aware of at which stopping position the transport vehicle 10 is stopped by knowing from which second communication device 30 the transport vehicle 10 is obtaining information. Here, knowing includes obtaining some kind of information.

[0070] An example of an item grabbing operation according to this embodiment will be described below. As an example of an item grabbing operation, an operation in which the transport vehicle 10 grabs an item 100 placed on a shelf 50-5 in the second storage section will be described using Figure 5. Figure 5 shows changes in the signal states of the transport information and storage information during the item grabbing operation.

[0071] The vehicle control device 7 acquires information about the placement unit 60 at which the item is to be grasped from the upper controller. In other words, the placement unit 60 at which the item is to be grasped is set in the vehicle control device 7. Here, the information about the placement unit 60 at which the item is to be grasped includes, for example, information about the shelf 50-5 at which the item is to be grasped (hereinafter referred to as "item grasp destination shelf information") and the position at which the transport vehicle 10 should stop to grasp the item 100 (hereinafter referred to as "item grasp stop set position"). Note that the item grasp destination shelf information is an example of transfer destination shelf information.

[0072] The vehicle control device 7 stops the transport vehicle 10 at a load grabbing stop set position, which is a stop position corresponding to the loading section 60 where the load is to be grabbed, among a plurality of stop positions. When the transport vehicle 10 stops at the load grabbing stop set position, interlock communication is performed between the first communication device 20 and the second communication device 30. In the following description, an example will be given in which the second communication device 30 corresponding to the load grabbing stop set position is the "second communication device 30c." In the interlock communication, the transport information shown in FIG. 5 is constantly transmitted from the first communication device 20 to the second communication device 30c, and the second communication device 30c constantly transmits the storage information shown in FIG. 5 to the first communication device 20.

[0073] When the transport vehicle 10 stops at the cargo gripping stop position, the vehicle control device 7 turns on the Valid_A signal (step S101). The storage control device 70 detects that the Valid_A signal is on and, if no transfer is taking place within the storage device 40, turns on the Valid_P signal (step S102). After turning on the Valid_P signal, the storage control device 70 turns on the On_Duty signal inside the storage control device 70 (step S103).

[0074] For example, when the On_Duty signal is OFF, the storage control device 70 may determine that no transfer is being performed within the storage device 40. The On_Duty signal is an internal signal of the storage control device 70, and indicates whether or not a transfer operation is in progress. When the On_Duty signal is ON, it indicates that a transfer operation is in progress, and when the On_Duty signal is OFF, it indicates that a transfer operation is not being performed.

[0075] When the vehicle control device 7 detects that the Valid_P signal is ON via the first communication device 20, it causes the first communication device 20 to transmit information about shelf 50-5 (item-grabbing shelf information) to the second communication device 30 (step S104). For example, when only the RTN1 signal and the RTN3 signal are ON, this indicates that the item-grabbing shelf information is shelf 50-5. Therefore, as illustrated in FIG. 5, in step S104, the vehicle control device 7 turns ON only the RTN1 signal and the RTN3 signal, thereby transmitting information about shelf 50-5 as item-grabbing shelf information to the storage control device 70.

[0076] When the storage control device 70 detects an RTN signal in which only the RTN1 signal and the RTN3 signal are ON, i.e., the item-grabbing-destination shelf information indicating shelf 50-5, it determines the presence or absence of the item 100 on the loading section 60 designated by the ATN signal based on the detection result of the detection unit 45. The storage control device 70 then transmits a CarrierDetect signal indicating the presence or absence of the item 100 on the loading section 60 designated by the item-grabbing-destination shelf information (step S105). In other words, the storage control device 70 turns the CarrierDetect signal ON if the item 100 is present on the loading section 60 designated in the item-grabbing-destination shelf information, and turns the CarrierDetect signal OFF if the item 100 is not present on the loading section 60.

[0077] The storage control device 70 can identify the loading section 60 at which the goods are to be unloaded, for example, based on the goods-grabbing-destination shelf information and information on the stop position (goods-grabbing stop position) at which the transport vehicle 10 is stopped. However, without being limited to this, the storage control device 70 may acquire information on the loading section 60 at which the goods are to be unloaded from the transport vehicle 10 through interlock communication.

[0078] Here, the CarrierDetect signal is, for example, one-bit information that is ON / OFF and indicates the presence or absence of an item 100. This allows the transport vehicle 10 to determine whether or not to seize an item with a small amount of communication traffic. In the example shown in FIG. 5, when the CarrierDetect signal is OFF, seizing an item is prohibited, and when the CarrierDetect signal is ON, seizing an item is permitted. The example shown in FIG. 5 assumes that an item 100 is placed on the placement section 60 where the item is to be seized. Therefore, the storage control device 70 turns the CarrierDetect signal ON in step S105.

[0079] When the vehicle control device 7 confirms that the CarrierDetect signal is ON, it turns the Permission signal ON (step S106). In other words, when the vehicle control device 7 confirms by the CarrierDetect signal that the item 100 to be grabbed is present on the shelf 50-5, it changes the signal state of the Permission signal, which is an example of a determination signal, from a prohibited state to a permitted state. This allows movement of the shelf 50-5. The Permission signal is an example of a determination signal. When the Permission signal is ON, movement of the shelf is permitted. When the Permission signal is OFF, movement of the shelf is prohibited.

[0080] When the storage control device 70 detects an RTN signal in which only the RTN1 signal and the RTN3 signal are ON and a Permission signal that is ON, it moves the shelf 50-5 from the retracted position to the transfer position. When the storage control device 70 starts moving the shelf 50-5 to the transfer position, it turns ON the Motion signal, which is an internal signal (step S107). When the shelf 50-5 arrives at the transfer position, the storage control device 70 turns OFF the Motion signal (step S108).

[0081] When shelf 50-5 arrives at the transfer position, the storage control device 70 causes the second communication device 30c to transmit mobile shelf information identifying the shelf present at the transfer position, i.e., information indicating shelf 50-5, to the first communication device 20 (step S109). In the example shown in Figure 5, the fact that only the ATN1 signal and the ATN3 signal are ON indicates that the mobile shelf information is shelf 50-5. Therefore, in step S109, the storage control device 70 transmits information about shelf 50-5 to the transport vehicle 10 as mobile shelf information by turning on only the ATN1 signal and the ATN3 signal.

[0082] The vehicle control device 7 detects an ATN signal in which only the ATN1 signal and the ATN3 signal are ON, i.e., movable shelf information indicating shelf 50-5, and if the CarrierDetect signal is ON at that time, turns the Permission signal OFF (step S110). That is, when the vehicle control device 7 confirms that shelf 50-5 on which the item 100 to be grasped is placed has moved from the retracted position to the transfer position, it changes the signal state of the Permission signal, which is an example of a determination signal, from a permitted state to a prohibited state. Then, the vehicle control device 7 starts the operation of grasping the item 100 on the transport vehicle 10 (step S111).

[0083] In this way, when the transport vehicle 10 completes the movement of the shelf 50-5 to the transfer position and there is an item 100 on the loading section 60 where the item is to be grabbed, it changes the judgment signal to a prohibited state and then begins the operation of grabbing the item 100.

[0084] The transport vehicle 10 lowers the holding unit 14, and holds the item 100 on the loading unit 60 of the shelf 50-5 that is the destination of the item grab with the holding unit 14. When the detection unit 45 detects that the item 100 is not on the loading unit 60 that is the destination of the item grab, the storage control device 70 turns the CarrierDetect signal OFF (step S112).

[0085] For example, when the detection results of the placement sensor and the presence sensor corresponding to the loading section 60 at the load-grabbing destination both indicate that the item 100 is not present, the storage control device 70 determines that there is no item on the loading section 60 at the load-grabbing destination and turns the CarrierDetect signal OFF. A result indicating that the item 100 is not present is, for example, when the output signals of the placement sensor and the presence sensor are both OFF.

[0086] After holding the article 100, the transport vehicle 10 raises the holding unit 14 to a predetermined position (e.g., the storage space AS) and moves the holding unit 14 out of the lifting area S. This completes the operation of grabbing the article 100 (step S113).

[0087] When the operation of grabbing the article 100 is completed and the CarrierDetect signal is OFF, the vehicle control device 7 turns OFF the RTN1 signal and the RTN3 signal (step S114). After step S114, the vehicle control device 7 turns ON the Permission signal (step S115). That is, when the vehicle control device 7 confirms in step S115 by the CarrierDetect signal that the article 100 to be grabbed is not present on the shelf 50-5 located in the transfer position, it changes the state of the Permission signal, which is an example of a determination signal, from a prohibited state to a permitted state.

[0088] In this way, the vehicle control device 7 prohibits the movement of the shelf 50-5 by constantly controlling the Permission signal, which is an example of a determination signal, to be OFF while the item-grabbing operation is being performed. This allows the vehicle control device 7 to appropriately control the movable shelf so that the shelf 50-5 does not return to the retracted position from the transfer position while the item-grabbing operation is being performed.

[0089] After the load grabbing operation is performed as a transfer operation, if all of the RTN signals are OFF and the Permission signal is ON (permitted state), this means that the transfer is completed by the transport vehicle 10. After this, the vehicle control device 7 does not check the Valid_P signal.

[0090] When the storage control device 70 detects that all of the RTN signals are OFF and that the Permission signal is ON, it turns OFF the ATN1 signal and the ATN3 signal (step S116) and starts the retreat operation of the shelf 50-5 (step S117). Note that the storage control device 70 may execute step S117 if, in step S116, all of the RTN1 signals are OFF, the Permission signal is ON, and there is no collapse of the goods 100. Note that there is a collapse of the goods 100 when, for example, the logic of the detection result of the placement sensor and the logic of the detection result of the presence sensor do not match.

[0091] After confirming that all ATN signals are OFF, the vehicle control device 7 turns OFF the Permission signal (step S118). The processing of step S118 may be executed while the shelf 50-5 is moving backward. For example, the vehicle control device 7 may turn OFF the Permission signal while the shelf 50-5 is being moved from the transfer position to the evacuation position. Furthermore, the vehicle control device 7 may turn OFF the Permission signal when, for example, the shelf 50-5 has completed moving from the transfer position to the evacuation position. Note that in step S118, the vehicle control device 7 may turn OFF the Permission signal when a specified time has elapsed since the completion of the item grabbing operation, even if not all ATN signals are OFF.

[0092] When the vehicle control device 7 turns OFF the Permission signal, it also turns OFF the Valid_A signal (step S119). When the storage control device 70 turns OFF all the ATN signals, it also turns OFF the Valid_P signal (step S120). After that, when the retreating operation of the shelf 50-5 is completed, the storage control device 70 turns OFF the On_Duty signal (step S121).

[0093] An example of an unloading operation according to this embodiment will be described below. As an example of the unloading operation, the operation when the transport vehicle 10 unloads onto shelf 50-5 in the second storage section will be described using Figure 6. Figure 6 shows changes in the signal states of the transport information and storage information during the unloading operation.

[0094] The vehicle control device 7 acquires information about the unloading destination placement unit 60 from the upper controller. In other words, the unloading destination placement unit 60 is set in the vehicle control device 7. Here, the information about the unloading destination placement unit 60 includes information about the unloading destination shelf 50-5 (hereinafter referred to as "unloading destination shelf information") and a position where the transport vehicle 10 should stop to unload the item 100 onto the unloading destination placement unit 60 (hereinafter referred to as "unloading stop position"). The unloading destination shelf information is an example of transfer destination shelf information.

[0095] The vehicle control device 7 stops the transport vehicle 10 at an unloading stop set position, which is a stop position corresponding to the loading section 60 at the unloading destination, among a plurality of stop positions. When the transport vehicle 10 stops at the unloading stop set position, interlock communication is performed between the first communication device 20 and the second communication device 30 corresponding to the unloading stop set position. In the following description, an example will be given in which the second communication device 30 corresponding to the unloading stop set position is the "second communication device 30b." In the interlock communication, the first communication device 20 constantly transmits the transport information shown in FIG. 6 to the second communication device 30b, and the second communication device 30b constantly transmits the storage information shown in FIG. 6 to the first communication device 20.

[0096] When the transport vehicle 10 stops at the set unloading stop position, the vehicle control device 7 turns on the Valid_A signal (step S201). In other words, when the transport vehicle 10 stops at the set unloading stop position, the first communication device 20 transmits the Valid_A signal (ON) to the second communication device 30b corresponding to the set unloading stop position.

[0097] The storage control device 70 detects that the Valid_A signal is ON and, if no transfer of the item 100 is being performed within the storage device 40, turns ON the Valid_P signal in the storage information (step S202). For example, the storage control device 70 may determine that no transfer is being performed within the storage device 40 if no other transport vehicle 10 is performing a transfer at a stop position other than the set unloading stop position.

[0098] When the storage control device 70 turns on the Valid_P signal in step S202, it turns on the On_Duty signal inside the storage control device 70 (step S203). When the On_Duty signal is on, the storage control device 70 does not accept signals from second communication devices 30 other than the second communication device 30b, and does not operate any shelves 50 other than the shelf 50-5 at the unloading destination.

[0099] When the vehicle control device 7 detects that the Valid_P signal is ON via the first communication device 20, it causes the first communication device 20 to transmit destination shelf information, i.e., information indicating shelf 50-5, to the second communication device 30b (step S204). In the example shown in Figure 6, the fact that only the RTN1 signal and the RTN3 signal are ON indicates that the destination shelf information is shelf 50-5. Therefore, in step S204, the vehicle control device 7 transmits information about shelf 50-5 to the storage control device 70 as destination shelf information by turning ON only the RTN1 signal and the RTN3 signal.

[0100] When the storage control device 70 detects an RTN signal in which only the RTN1 signal and the RTN3 signal are ON, i.e., the unloading destination shelf information indicating shelf 50-5, it determines the presence or absence of the item 100 on the unloading destination placement section 60 specified by the ATN signal based on the detection result of the detection unit 45. The storage control device 70 transmits a CarrierDetect signal indicating the presence or absence of the item 100 on the unloading destination placement section 60. The example shown in Figure 6 assumes that, in the initial state, no item 100 is placed on the unloading destination placement section 60.

[0101] When the vehicle control device 7 confirms that the CarrierDetect signal is OFF, it turns the Permission signal ON (step S205). That is, in step S205, when the vehicle control device 7 confirms by the CarrierDetect signal that no article 100 is present on the unloading destination shelf 50-5, it changes the signal state of the Permission signal, which is an example of a determination signal, from a prohibited state to a permitted state. As a result, movement of the shelf 50-5 becomes permitted.

[0102] When the storage control device 70 detects an RTN signal in which only the RTN1 signal and the RTN3 signal are ON and a Permission signal that is ON, it moves the shelf 50-5 from the retracted position to the transfer position. When the storage control device 70 starts moving the shelf 50-5 to the transfer position, it turns ON the Motion signal, which is an internal signal (step S206). When the shelf 50-5 arrives at the transfer position, the storage control device 70 turns OFF the Motion signal (step S207).

[0103] When shelf 50-5 arrives at the transfer position, the storage control device 70 causes the second communication device 30b to transmit mobile shelf information identifying the shelf present at the transfer position, i.e., information indicating shelf 50-5, to the first communication device 20 (step S208). In the example shown in Figure 6, the fact that only the ATN1 signal and the ATN3 signal are ON indicates that the mobile shelf information is shelf 50-5. Therefore, in step S208, the storage control device 70 transmits information about shelf 50-5 to the transport vehicle 10 as mobile shelf information by turning on only the ATN1 signal and the ATN3 signal.

[0104] The vehicle control device 7 detects an ATN signal in which only the ATN1 signal and the ATN3 signal are ON, i.e., movable shelf information indicating shelf 50-5, and if the CarrierDetect signal is OFF at that time, it turns the Permission signal OFF (step S209). That is, when the vehicle control device 7 confirms that shelf 50-5 has moved from the retracted position to the transfer position, it changes the signal state of the Permission signal, which is an example of a determination signal, from a permitted state to a prohibited state. Then, the vehicle control device 7 starts the unloading operation of the article 100 on the transport vehicle 10 (step S210).

[0105] In this way, after the movement of the shelf 50-5 to the transfer position is completed, the transport vehicle 10 changes the determination signal to the prohibited state and starts the unloading operation of the article 100.

[0106] The transport vehicle 10 lowers the holding unit 14 holding the item 100, and places the item 100 on the destination loading unit 60 on the shelf 50-5. When the detection unit 45 detects that an item is present on the destination loading unit 60, the storage control device 70 turns the CarrierDetect signal ON (step S211).

[0107] For example, if the detection results of the placement sensor and the presence sensor corresponding to the loading section 60 at the unloading destination both indicate that an item 100 is present, the storage control device 70 turns on the CarrierDetect signal, indicating that an item is present on the loading section 60 at the unloading destination.

[0108] After placing the article 100 on the placement section 60, the transport vehicle 10 raises the holding section 14 to a predetermined position and moves the holding section 14 out of the lifting area S. This completes the unloading operation (step S212).

[0109] When the unloading of the article 100 is completed and the CarrierDetect signal is ON, the vehicle control device 7 turns OFF the RTN1 signal and the RTN3 signal (step S213). Furthermore, after step S213, the vehicle control device 7 turns ON the Permission signal (step S214). That is, when the vehicle control device 7 confirms in step S214 by the CarrierDetect signal that the unloaded article 100 is present on the shelf 50-5 at the transfer position, it changes the state of the Permission signal, which is an example of a determination signal, from a prohibited state to a permitted state.

[0110] In this way, the vehicle control device 7 prohibits the movement of the shelf 50-5 by constantly controlling the Permission signal, which is an example of a determination signal, to be OFF while the unloading operation is being performed. This allows the vehicle control device 7 to appropriately control the movable shelf so that the shelf 50-5 does not return to the retracted position from the transfer position while the unloading operation is being performed.

[0111] After the unloading operation as the transfer operation is executed, if all of the RTN signals are ON and the Permission signal is ON (permitted state), this means that the transfer by the transport vehicle 10 is completed. After this, the vehicle control device 7 does not check the Valid_P signal.

[0112] If the storage control device 70 detects that all of the RTN signals are OFF and that the Permission signal is ON, it turns OFF the ATN1 signal and the ATN3 signal (step S215) and starts the retreat operation of the shelf 50-5 (step S216). Note that the storage control device 70 may execute step S216 if, in step S215, all of the RTN1 signals are OFF, the Permission signal is ON, and further, no collapse of the goods 100 has occurred.

[0113] After confirming that all ATN signals are OFF, the vehicle control device 7 turns OFF the Permission signal (step S217). The processing of step S217 may be executed while the shelf 50-5 is moving backward. For example, the vehicle control device 7 may turn OFF the Permission signal while the shelf 50-5 is being moved from the transfer position to the evacuation position. Furthermore, the vehicle control device 7 may turn OFF the Permission signal when, for example, the shelf 50-5 has completed moving from the transfer position to the evacuation position. Note that in step S217, the vehicle control device 7 may turn OFF the Permission signal when a specified time has elapsed since the unloading operation was completed, even if not all ATN signals are OFF.

[0114] When the vehicle control device 7 turns OFF the Permission signal, it also turns OFF the Valid_A signal (step S218). When the storage control device 70 turns OFF all ATN signals, it also turns OFF the Valid_P signal and the CarrierDetect signal (step S219). After that, when the retreating operation of the shelf 50-5 is completed, the storage control device 70 turns OFF the On_Duty signal (step S220).

[0115] An example of the operation of the check function according to this embodiment will be described below. The transport system HS may have a check function that checks whether an article 100 is placed on the placement section 60 of a specific shelf 50. For example, the transport vehicle 10 has the check function of checking whether an article 100 is present on the shelf 50 while maintaining the signal state of the determination signal in a prohibited state.

[0116] As an example of the check function, an example of checking whether an item 100 is placed on each of the placement sections 60 in a specific row (e.g., any of the first to fourth rows) of shelves 50-5, 50-6, and 50-7 will be described with reference to FIG. 7. FIG. 7 shows changes in the signal states of the transport information and storage information during the check function. In the example shown in FIG. 7, the transport system HS checks whether an item 100 is placed on shelves 50-5, 50-6, and 50-7 in that order.

[0117] The vehicle control device 7 acquires information about the target placement unit 60 from the higher-level controller. In other words, the target placement unit 60 is set in the vehicle control device 7. Here, the information about the target placement unit 60 includes information about the target shelf 50-5 (hereinafter referred to as "target shelf information") and a position where the transport vehicle 10 should stop to check whether the item 100 is placed on the target placement unit 60 (hereinafter referred to as "target stop position").

[0118] The vehicle control device 7 stops the transport vehicle 10 at a confirmation stop setting position among a plurality of stop positions. When the transport vehicle 10 stops at the confirmation stop setting position, communication is performed between the first communication device 20 and the second communication device 30 corresponding to the confirmation stop setting position. In the following explanation, a case where the second communication device 30 corresponding to the confirmation stop setting position is the "second communication device 30a" will be described as an example. The transport information shown in FIG. 7 is constantly transmitted from the first communication device 20 to the second communication device 30a, and the second communication device 30a constantly transmits the storage information shown in FIG. 7 to the first communication device 20.

[0119] When the transport vehicle 10 stops at the set confirmation stop position, the vehicle control device 7 turns on the Valid_A signal (step S301). In other words, when the transport vehicle 10 stops at the set confirmation stop position, the first communication device 20 transmits the Valid_A signal turned on to the second communication device 30a corresponding to the set confirmation stop position.

[0120] The storage control device 70 turns on the Valid_P signal in the storage information (step S302) if it detects that the Valid_A signal is ON and if the item 100 is not being transferred within the storage device 40. When the storage control device 70 turns on the Valid_P signal in step S302, it turns on the On_Duty signal inside the storage control device 70 (step S303).

[0121] In order to check whether the item 100 is present on the shelf 50-5, the vehicle control device 7 transmits information about the shelf 50-5 as confirmation shelf information to the storage control device 70 by turning on only the RTN1 signal and the RTN3 signal (step S304). However, because there is no need to operate the shelf 50, the vehicle control device 7 leaves the Permission signal OFF.

[0122] When the storage control device 70 detects an RTN signal in which only the RTN1 signal and the RTN3 signal are ON, i.e., confirmation shelf information indicating shelf 50-5, it determines whether or not the item 100 is present on shelf 50-5 specified by the RTN signal based on the detection result of the detection unit 45. The storage control device 70 transmits a CarrierDetect signal indicating the determination result. The example shown in FIG. 7 assumes that the item 100 is placed on the placement section 60 of shelf 50-5. Therefore, when the storage control device 70 detects confirmation shelf information indicating shelf 50-5, it turns the CarrierDetect signal ON (step S305). This allows the vehicle control device 7 to confirm the presence or absence of the item 100 on shelf 50-5.

[0123] Next, in order to check whether or not the item 100 is present on the shelf 50-6, the vehicle control device 7 turns on only the RTN2 signal and the RTN3 signal, thereby transmitting information about the shelf 50-6 as the shelf information to be checked to the storage control device 70 (step S306).

[0124] When the storage control device 70 detects an RTN signal in which only the RTN2 signal and the RTN3 signal are ON, i.e., confirmation shelf information indicating shelf 50-6, it determines the presence or absence of the item 100 on shelf 50-6 specified by the RTN signal based on the detection result of the detection unit 45. The storage control device 70 transmits a CarrierDetect signal indicating the determination result. The example shown in FIG. 7 assumes that no item 100 is placed on the placement section 60 of shelf 50-6. Therefore, when the storage control device 70 detects confirmation shelf information indicating shelf 50-6, it turns the CarrierDetect signal OFF (step S307). This allows the vehicle control device 7 to confirm the presence or absence of the item 100 on shelf 50-6.

[0125] Next, in order to confirm whether or not the item 100 is present on the shelf 50-7, the vehicle control device 7 turns on only the RTN1 signal, the RTN2 signal, and the RTN3 signal, thereby transmitting information about the shelf 50-7 as the shelf information to be checked to the storage control device 70 (step S308).

[0126] When the storage control device 70 detects an RTN signal in which only the RTN1 signal, the RTN2 signal, and the RTN3 signal are ON, i.e., confirmation shelf information indicating the shelf 50-7, it determines the presence or absence of the item 100 on the shelf 50-7 specified by the RTN signal based on the detection result of the detection unit 45. The storage control device 70 transmits a CarrierDetect signal indicating the determination result. The example shown in FIG. 7 assumes that the item 100 is placed on the placement section 60 of the shelf 50-7. Therefore, when the storage control device 70 detects confirmation shelf information indicating the shelf 50-7, it turns the CarrierDetect signal ON (step S309). This allows the vehicle control device 7 to confirm the presence or absence of the item 100 on the shelf 50-7.

[0127] The vehicle control device 7 turns off all RTN signals because it has completed checking for the presence or absence of all items on shelves 50-5, 50-6, and 50-7 (step S310). Next, the vehicle control device 7 turns on the Permission signal (step S311). The fact that all RTN signals are off and the Permission signal has turned on means that the work of checking for the presence or absence of item 100 has been completed. After this, the vehicle control device 7 does not check the Valid_P signal.

[0128] When all the RTN signals are turned OFF, the storage control device 70 turns OFF the CarrierDetect signal. When the storage control device 70 detects that all the RTN signals are OFF and the Permission signal is ON, it turns OFF all the ATN signals. After this, the storage control device 70 does not check the transport information.

[0129] When the vehicle control device 7 confirms that all ATN signals are OFF, it turns OFF the Permission signal (step S312). Note that even if not all ATN signals are OFF, the vehicle control device 7 may turn OFF the Permission signal after a specified time has elapsed since turning ON the Permission signal. When turning OFF the Permission signal, the vehicle control device 7 turns OFF the Valid_A signal (step S313).

[0130] When all the ATN signals have been turned OFF, the storage control device 70 turns OFF the Valid_P signal (step S314) and turns OFF the On_Duty signal (step S315). This completes the series of operations of the confirmation function shown in Figure 7. In this way, the transport vehicle 10 can confirm whether or not an article 100 is present on the shelf 50 without moving the shelf 50.

[0131] The above embodiment discloses the following configurations. (Configuration 1) A transport system HS includes a transport vehicle 10 that transports an item 100 and a storage device 40 to which the transport vehicle 10 transfers the item 100. The transport vehicle 10 includes a first communication device 20 that communicates with the storage device 40 to transfer the item 100. The storage device 40 includes a second communication device 30 that communicates with the first communication device 20, and a shelf 50 that stores the item 100. The transport vehicle 10 transmits a determination signal indicating whether or not movement of the shelf 50 is permitted to the second communication device 30 via the first communication device 20. The storage device 40 moves the shelf 50 to a transfer position or a retreat position only when the determination signal acquired via the second communication device 30 indicates that movement of the shelf 50 is permitted. (Configuration 2) In Configuration 1, the storage device 40 may move the shelf 50 to the retracted position only when the determination signal indicates permission to move the shelf 50 when the shelf 50 is located at the transfer position. (Configuration 3) In Configuration 1 or Configuration 2, when the transport vehicle 10 grasps an item 100 placed on the shelf 50, upon confirming that the shelf 50 on which the item 100 to be grasped is placed has moved from the retracted position to the transfer position (for example, upon receiving the ATN signal shown in step S109), the transport vehicle 10 may change the signal state of the determination signal from the permitted state to the prohibited state (for example, step S110). Then, after completing the grasp (for example, step S113), upon confirming that the item 100 to be grasped is not present on the shelf 50 at the transfer position (for example, the CarrierDetect signal is OFF), the transport vehicle 10 may change the state of the determination signal from the prohibited state to the permitted state (for example, step S115). (Configuration 4) In any of configurations 1 to 3, when the transport vehicle 10 grasps an item 100 placed on a shelf 50, if the transport vehicle 10 confirms that the item 100 to be grasped is present on the shelf 50 (e.g., shelf 50-5) (e.g., if the transport vehicle 10 confirms that the CarrierDetect signal has been turned ON in step S105), the transport vehicle 10 may change the signal state of the determination signal from a prohibited state to an permitted state (e.g., step S106).When the storage device 40 detects that the signal state of the determination signal has changed from the prohibition state to the permission state, the storage device 40 moves the shelf (e.g., shelf 50-5) on which the item 100 to be grasped is placed from the retracted position to the transfer position so that the transport vehicle 10 can grasp the item 100 at the transfer position. Then, the transport vehicle 10 grasps the item 100 on the shelf 50-5 (e.g., step S111). After the item grasping is completed (e.g., step S113), the transport vehicle 10 may change the signal state of the determination signal from the permission state to the prohibition state while the shelf 50 is being moved from the transfer position to the retracted position (e.g., while the Motion signal illustrated in FIG. 5 is ON ("Move Backward")) or when the movement is completed (e.g., step S118). (Configuration 5) In any of configurations 1 to 4, when the transport vehicle 10 unloads the item 100 onto the shelf 50, upon confirming that the shelf 50 has moved from the retracted position to the transfer position (for example, upon receiving the ATN signal shown in step S208), the transport vehicle 10 may change the signal state of the determination signal from the permitted state to the prohibited state (for example, step S209). In this case, the transport vehicle 10 unloads the item 100 onto the shelf 50 that is in the transfer position in the prohibited state (step S210), and upon confirming that the item 100 is present on the shelf 50 (for example, the CarrierDetect signal is ON), the transport vehicle 10 may change the state of the determination signal from the prohibited state to the permitted state (step S214). (Configuration 6) In any of configurations 1 to 5, when the transport vehicle 10 confirms that the item 100 is not present on the shelf 50 at the unloading destination (e.g., the CarrierDetect signal is OFF) before unloading the item 100, the transport vehicle 10 may change the signal state of the determination signal from a prohibition state to an authorization state (e.g., step S205). When the storage device 40 detects that the signal state of the determination signal has changed from a prohibition state to an authorization state, it moves the shelf 50 at the unloading destination (e.g., shelf 50-5) from the retracted position to the transfer position to execute the unloading. Then, when the shelf 50-5 moves to the transfer position, the transport vehicle 10 executes unloading of the item 100 onto the shelf 50-5 (e.g., step S210).When the transport vehicle 10 completes unloading, the storage device 40 moves the shelf 50-5 from the transfer position to the retracted position. After the transport vehicle 10 completes unloading of the items 100 onto the shelf 50-5, and confirms that the shelf 50-5 has moved from the transfer position to the retracted position (for example, when it confirms that all ATN signals are OFF), the storage device 40 may change the signal state of the determination signal from the permitted state to the prohibited state (for example, step S217). (Configuration 7) In any of configurations 1 to 6, the transport vehicle 10 may check whether the items 100 are present on the shelf 50 while maintaining the signal state of the determination signal transmitted from the first communication device 20 to the second communication device 30 in the prohibited state. (Configuration 8) In any of configurations 1 to 8, the storage device 40 may include shelves 50 that are movable shelves. The storage device 40 may move the specific shelf 50-5 when the determination signal indicates permission to move the shelf 50 and identification information (transfer destination shelf information, for example, an RTN signal) of the specific shelf 50 to be moved (for example, shelf 50-5) is acquired via the first communication device 20. On the other hand, the storage device 40 may not move the specific shelf 50-5 when the determination signal indicates prohibition of movement of the shelf 50 and identification information (transfer destination shelf information, for example, an RTN signal) of the specific shelf 50 to be moved (for example, shelf 50-5) is acquired via the first communication device 20. (Configuration 9) The transport method according to the present embodiment includes the transport vehicle 10 transmitting a determination signal to the storage device 40 indicating whether or not to permit the movement of the shelf 50, and the storage device 40 moving the shelf 50 to the transfer position or the evacuation position only when the acquired determination signal indicates permission to move the shelf 50.(Configuration 10) Configuration 9 may include the following: when the transport vehicle 10 grabs the item 100 placed on the shelf 50, the signal state of the determination signal is changed from a prohibition state indicating that movement of the shelf 50 is prohibited to a permission state indicating that movement of the shelf 50 is permitted; when the storage device 40 detects the permission state of the determination signal, the storage device 40 moves the shelf 50 from the retracted position to the transfer position; when the shelf 50 moves from the retracted position to the transfer position, the transport vehicle 10 changes the signal state of the determination signal from the permission state to the prohibition state and grabs the item 100 on the shelf 50; when the transport vehicle 10 confirms that the item 100 to be grabbed is not present on the shelf 50, the storage device 40 changes the state of the determination signal from the prohibition state to the permission state; and when the storage device 40 detects the permission state of the determination signal after the grab is completed, the storage device 40 moves the shelf 50 from the transfer position to the retracted position. (Configuration 11) Configuration 9 or 10 may include the following: when the transport vehicle 10 unloads the item 100, the signal state of the determination signal is changed from a prohibited state to a permitted state; when the storage device 40 detects the permitted state of the determination signal, the storage device 40 moves the shelf 50 at the unloading destination from the retracted position to the transfer position; when the shelf 50 moves from the retracted position to the transfer position, the transport vehicle 10 changes the signal state of the determination signal from the permitted state to a prohibited state and unloads the item 100; when the transport vehicle 10 confirms that the item 100 is present on the shelf 50 at the unloading destination, the storage device 40 changes the state of the determination signal from the prohibited state to the permitted state; and when the storage device 40 detects the permitted state of the determination signal after unloading onto the shelf 50 is completed, the storage device 40 moves the shelf 50 from the transfer position to the retracted position.

[0132] One or more of the requirements described in the above-described embodiments may be omitted. Furthermore, the requirements described in the above-described embodiments may be combined as appropriate. Furthermore, the execution order of each procedure shown in this embodiment can be realized in any order as long as the results of a previous procedure are not used in a subsequent procedure. Furthermore, even if the operations in the above-described embodiments are described using terms such as "first," "next," and "subsequently" for convenience, it is not necessary to perform the operations in this order. Furthermore, to the extent permitted by law, the disclosures of Japanese Patent Application No. 2024-070486 and all documents cited in the above-described embodiments are incorporated herein by reference.

[0133] HS...transport system, 7...vehicle control device, 10...transport vehicle, 20...first communication device, 30...second communication device, 40...storage device, 50...shelf, 45...detection unit, 70...storage control device

Claims

1. A conveyance system comprising a transport vehicle that transports items and a storage device to which the items are transferred by the transport vehicle, wherein the transport vehicle has a first communication device that communicates with the storage device to transfer the items, the storage device has a second communication device that communicates with the first communication device, and a movable shelf that stores the items, wherein the movable shelf is movable between a transfer position to which the items are transferred by the transport vehicle and a retracted position where the movable shelf is retracted from the transfer position, the transport vehicle transmits a determination signal to the second communication device via the first communication device indicating whether or not movement of the movable shelf is permitted, and the storage device moves the movable shelf to the transfer position or the retracted position only if the determination signal obtained via the second communication device indicates that movement of the movable shelf is permitted.

2. The transport system according to claim 1, wherein the storage device moves the movable shelf to the retracted position only when the determination signal indicates that movement of the movable shelf is permitted when the movable shelf is located at the transfer position.

3. The transport vehicle sets the signal state of the determination signal to either a permitted state indicating that movement of the movable shelf is permitted or a prohibited state indicating that movement of the movable shelf is prohibited, and when the transport vehicle is grabbing an item placed on the movable shelf, it changes the signal state of the determination signal from the permitted state to the prohibited state upon confirming that the movable shelf on which the item to be grabbed is placed has moved from the retracted position to the transfer position, and when the transport vehicle grabs the item and confirms that the item to be grabbed is not present on the movable shelf at the transfer position, it changes the signal state of the determination signal from the prohibited state to the permitted state. A transport system as described in claim 2.

4. The transport vehicle, when grabbing the item placed on the movable shelf, changes the signal state of the determination signal from the prohibited state to the permitted state when it confirms that the item to be grabbed is present on the movable shelf, and after grabbing the item, changes the signal state of the determination signal from the permitted state to the prohibited state when the movable shelf is in the process of moving from the transfer position to the retracted position or when said movement has been completed. The transport system of claim 3.

5. The transport vehicle sets the signal state of the determination signal to either a permitted state indicating that movement of the movable shelf is permitted or a prohibited state indicating that movement of the movable shelf is prohibited, and when the transport vehicle unloads the item onto the movable shelf, it changes the signal state of the determination signal from the permitted state to the prohibited state upon confirming that the movable shelf has moved from the retracted position to the transfer position, and when the transport vehicle unloads the item onto the movable shelf at the transfer position and confirms that the item is present on the movable shelf, it changes the state of the determination signal from the prohibited state to the permitted state. A transport system as described in claim 2.

6. The transport system of claim 3, wherein, when unloading the item, the transport vehicle changes the signal state of the determination signal from the prohibited state to the permitted state when it confirms that the item is not present on the movable shelf at the unloading destination, and after unloading of the item onto the movable shelf is completed, when it confirms that the movable shelf has moved from the transfer position to the retracted position, it changes the signal state of the determination signal from the permitted state to the prohibited state.

7. A conveying system as described in claim 3 or claim 5, wherein the conveying vehicle checks whether the item is present on the movable shelf while maintaining the signal state of the determination signal transmitted from the first communication device to the second communication device in the prohibited state.

8. The transport system of claim 1, wherein the storage device is equipped with a plurality of movable shelves, and the storage device moves the specific movable shelf when the determination signal indicates permission to move the movable shelf and identification information of the specific movable shelf to be moved is acquired via the first communication device, and does not move the specific movable shelf when the determination signal indicates prohibition of movement of the movable shelf and the identification information is acquired via the first communication device.

9. A transport method for a transport system comprising a transport vehicle that transports items and a storage device to which the items are transferred by the transport vehicle, wherein the transport vehicle and the storage device are capable of sending and receiving information to each other via wireless communication, the storage device stores the items and is equipped with a movable shelf that is movable between a transfer position and a retracted position, the transport vehicle transmitting a determination signal to the storage device indicating whether or not movement of the movable shelf is permitted, and the storage device moving the movable shelf to the transfer position or the retracted position only if the acquired determination signal indicates that movement of the movable shelf is permitted.

10. The transportation method according to claim 9, comprising: when the transport vehicle grabs the item placed on the movable shelf, changing the signal state of the determination signal from a prohibition state, indicating that movement of the movable shelf is prohibited, to a permission state, indicating that movement of the movable shelf is permitted; when the storage device detects the permission state of the determination signal, moving the movable shelf from the retracted position to the transfer position; when the movable shelf moves from the retracted position to the transfer position, the transport vehicle changes the signal state of the determination signal from the permission state to the prohibition state and grabs the item on the movable shelf; when the transport vehicle confirms that the item to be grabbed is not present on the movable shelf, changing the state of the determination signal from the prohibition state to the permission state; and when the storage device detects the permission state of the determination signal after the grab is completed, moving the movable shelf from the transfer position to the retracted position.

11. The transportation method according to claim 10, comprising: when the transport vehicle unloads the item, changing the signal state of the determination signal from the prohibited state to the permitted state; when the storage device detects the permitted state of the determination signal, moving the movable shelf at the unloading destination from the retracted position to the transfer position; when the movable shelf has moved from the retracted position to the transfer position, the transport vehicle changes the signal state of the determination signal from the permitted state to the prohibited state and unloads the item; when the transport vehicle confirms that the item is present on the movable shelf at the unloading destination, changing the state of the determination signal from the prohibited state to the permitted state; and when the storage device detects the permitted state of the determination signal after unloading onto the movable shelf is completed, moving the movable shelf from the transfer position to the retracted position.

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