Intake and retrieval system

Abstract

To provide a storage / delivery system capable of sufficiently reducing storage / delivery time, even when a frequency of storing / delivering cargoes is rapidly changed.SOLUTION: According to the present invention, a storage / delivery system (1) comprises: a rack (2) provided with a plurality of storage shelves; a conveying device (4) for performing storage / delivery processing of conveying cargoes (10) from the storage shelves to a storage / delivery station (8) and returning to the storage shelves (12); and a controller (6). The controller comprises a storage / delivery period storage part (6c) for storing a storage / delivery period of each cargo, and a storage shelf selection part (6d) for selecting a warehousing storage shelf to store a delivery cargo again. The storage shelf selection part selects the warehousing storage shelf in such a manner that shipping time required for conveyance from the storage shelves to the storage / delivery station becomes shipping time at the shipping time of the storage shelves, on which the delivery cargo is stored, or less, when the delivery cargo conveyed to the storage / delivery station is subjected to the storage / delivery processing within the latest past predetermined time.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a storage and retrieval system, and more particularly to a storage and retrieval system for storing, storing and retrieving luggage. [Background technology]

[0002] Automated warehouse systems are known that store cargo such as goods and retrieve the goods as needed. Such automated warehouse systems include multiple storage shelves for storing a large number of goods and a transport vehicle that transports pallets carrying the goods from the storage shelves to a storage / retrieval station. When a command to ship the stored goods is received, the transport vehicle transports the pallet carrying the goods from the storage shelves to the storage / retrieval station. Once the pallet is transported to the storage / retrieval station, a worker picks up the required number of goods from the pallet, and the pallet carrying the remaining goods is returned to the storage shelf by the transport vehicle.

[0003] Japanese Patent Laid-Open Publication No. 3-8602 (Patent Document 1) describes a shelf determination method for an automated warehouse. In this shelf determination method, the shelves of the automated warehouse are divided into multiple blocks based on the distance from the (storage / retrieval) station. Meanwhile, goods (baggage) to be stored and retrieved are classified according to the number of blocks in the automated warehouse based on the frequency of storage and retrieval, and when goods are received, they are stored on shelves in blocks closest to the station, starting with goods with a higher frequency of storage and retrieval. As a result, goods with a higher frequency of storage and retrieval are assigned to shelves belonging to blocks closest to the station, which shortens the transport time for transporting goods with a higher frequency of storage and retrieval to the station and improves the cycle time for storing and retrieving goods. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 3-8602 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the shelf determination method for an automated warehouse described in Patent Document 1 assigns products to each block using a master file that stores cumulative inventory counters by product number, which results in a problem of complex data processing for assigning shelves to each product. Furthermore, the shelf determination method for an automated warehouse described in Patent Document 1 assigns blocks based on the cumulative number of inventory entries for that product over a certain period. Therefore, even if the frequency of inventory entry and delivery of a certain product changes suddenly, the cumulative number of inventory entries changes gradually, making it impossible to reflect such sudden changes in shelf allocation. This results in a problem of being unable to sufficiently shorten inventory entry and delivery times.

[0006] Therefore, an object of the present invention is to provide a storage and retrieval system that can sufficiently shorten storage and retrieval times even when the frequency of storing and retrieving cargo changes suddenly. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides an entry / exit system for storing and entering / exiting luggage, the system comprising: a rack having a plurality of storage shelves for storing luggage; a transport device for performing entry / exit processing to transport luggage stored in the rack from the storage shelves of the rack to an entry / exit station and to return the luggage transported to the entry / exit station to an empty storage shelf of the rack; and a controller for controlling the transport device, the controller including: an entry / exit time memory unit for storing the entry / exit time when entry / exit processing was performed for each luggage stored in the rack; a storage shelf selection unit for selecting an entry storage shelf to which an outgoing luggage transported from a storage shelf of the rack to the entry / exit station should be re-stored based on the entry / exit time stored in the entry / exit time memory unit; a storage / retrieval frequency storage unit that stores the frequency of storage / retrieval processing within a predetermined period in the past for each item stored in the rack; Equipped with The storage shelves in the racks are divided into multiple rank areas according to the time required for retrieval. The storage shelf selection unit selects the time required for transporting the outgoing goods from the storage shelf to the ingoing / outgoing station when the outgoing goods have undergone ingoing / outgoing processing within the most recent predetermined time in the past. Within the area with the shortest rank Select receiving bin If the outgoing goods transported from the rack to the inbound / outbound station have not undergone inbound / outbound processing within the most recent predetermined time, the storage shelf selection unit selects an inbound storage shelf within an area of ​​a rank set according to the frequency of inbound / outbound processing stored in the inbound / outbound frequency storage unit. It is characterized by the following.

[0008] In the present invention configured as described above, the controller controls the conveying device to transport packages from the storage shelves of the rack to the loading / unloading station. The controller also includes a loading / unloading time memory unit that stores the loading / unloading time when the loading / unloading process was performed for each package stored on the rack. The storage shelf selection unit included in the controller selects an input storage shelf to which the outgoing package transported from the storage shelf of the rack to the loading / unloading station should be reloaded, based on the loading / unloading time stored in the loading / unloading time memory unit. If the outgoing package transported from the rack to the loading / unloading station was subjected to loading / unloading process within the most recent predetermined time, the storage shelf selection unit selects an input storage shelf so that the retrieval time required to transport the outgoing package from the storage shelf to the loading / unloading station is equal to or shorter than the retrieval time from the storage shelf where the outgoing package was stored.

[0009] According to the present invention configured as described above, if an outgoing item has undergone a loading / unloading process within the most recent predetermined time, an incoming storage shelf is selected so that the unloading time is equal to or shorter than the unloading time from the storage shelf where the outgoing item was stored. Therefore, the most recently loaded / unloaded item will be stored in a storage shelf with a shorter unloading time than the storage shelf where it was previously stored, or in a storage shelf with the same unloading time as the storage shelf where it was previously stored. This allows the item to be moved to a storage shelf with a shorter unloading time in a short period of time, even if the frequency of loading / unloading suddenly increases for a certain item, thereby significantly reducing the loading / unloading time. Furthermore, because the storage shelf is selected based solely on the loading / unloading time of the previous loading / unloading process, an appropriate storage shelf can be selected with simple information processing.

[0011] According to the present invention configured as described above, if an outgoing item has not been processed for storage or retrieval within the most recent predetermined time, an incoming storage shelf is selected based on the frequency of storage or retrieval. Therefore, even for items that have not been processed for storage or retrieval recently, an appropriate storage shelf can be assigned according to the frequency of storage or retrieval, thereby improving the overall efficiency of storage or retrieval processing.

[0012] In the present invention, preferably, the controller further includes an entry / exit timing confirmation unit that executes an entry / exit timing confirmation mode, and when the entry / exit timing confirmation mode is executed, the entry / exit timing confirmation unit identifies the time when the last entry / exit process was performed for each item stored on the rack based on the data stored in the entry / exit timing memory unit, and extracts any remaining items whose last entry / exit process was performed more than a predetermined number of days ago, and the controller moves the extracted remaining items to a storage shelf determined based on the frequency of entry / exit processes stored in the entry / exit frequency memory unit.

[0013] According to the present invention configured as described above, held-up luggage whose last loading / unloading process was more than a predetermined number of days ago is extracted, and the extracted held-up luggage is moved to a storage shelf determined based on the frequency of loading / unloading processes stored in the loading / unloading frequency storage unit. This makes it possible to prevent luggage that is infrequently loaded / unloaded from continuing to occupy storage shelves with short unloading times, and allows for efficient use of storage shelves with short unloading times. [Effects of the Invention]

[0014] According to the storage and retrieval system of the present invention, even if the frequency of storing and retrieving cargo changes suddenly, the storage and retrieval time can be sufficiently reduced. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a perspective view showing an entire warehousing and shipping system according to an embodiment of the present invention. [Figure 2] 2 is a block diagram showing the configuration of a controller provided in the warehousing / retrieval system according to the embodiment of the present invention. FIG. [Figure 3] 10 is a flowchart showing processing performed by a controller provided in the inventory-receiving system of the embodiment of the present invention when a product is retrieved. [Figure 4] 10 is a flowchart showing a process performed by a controller provided in the inventory-receiving system of the embodiment of the present invention when a commodity is stored. [Figure 5]10 is a flowchart showing processing in a storage / retrieval time confirmation mode by a controller provided in the storage / retrieval system of an embodiment of the present invention. [Figure 6] 1 is a schematic diagram showing an example of ranking of retrieval times in racks provided in the retrieval system according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] Next, a storage and retrieval system according to an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view showing the entire warehousing and shipping system according to an embodiment of the present invention, and Fig. 2 is a block diagram showing the configuration of a controller provided in the warehousing and shipping system according to an embodiment of the present invention.

[0017] 1, a storage / retrieval system 1 according to an embodiment of the present invention includes a rack 2 equipped with a plurality of storage shelves for storing products, a conveying device 4 for transporting the products stored on the rack 2, and a controller 6 for controlling the conveying device 4. The storage / retrieval system 1 further includes a storage / retrieval station 8 where a worker picks up the required number of products from a case containing a plurality of products to be transported by the conveying device 4.

[0018] In the storage / retrieval system 1 of this embodiment, when products stored on the rack 2 are to be shipped, the controller 6 controls the conveying device 4 to transport the products stored on the storage shelves of the rack 2 to the storage / retrieval station 8. Furthermore, when a worker picks up the required number of products from the products transported to the storage / retrieval station 8, the remaining products are returned to the rack 2 by the conveying device 4.

[0019] The rack 2 is provided with a plurality of storage shelves 12 for storing a plurality of cases 10, which are cargo containing a plurality of products. As shown in FIG. 1 , in this embodiment, the storage / retrieval system 1 is provided with two racks 2, each having a plurality of rows of storage shelves 12 with a plurality of tiers, and each storage shelf 12 of each rack 2 holds a case 10. In this embodiment, the storage shelves 12 for storing each case 10 are composed of beam-like members that engage with both sides of the case 10 to hold the case 10 in a predetermined position. As such, in this specification, the term "storage shelf" means any configuration that can hold cargo in a predetermined position, and does not necessarily consist of a plate-like member on which cases 10 containing products, etc., are placed.

[0020] Next, the transport device 4 has a transporting cart 14, a roller conveyor 16a that transports the case 10 unloaded from the rack 2 by this transporting cart 14 to the loading / unloading station 8, and a roller conveyor 16b that transports the case 10 from the loading / unloading station 8 to the rack 2. In this way, the transport device 4 is configured to transport the case 10 stored in the rack 2 from the storage shelf 12 of the rack 2 to the loading / unloading station 8, and to perform loading / unloading processing of returning the case 10 transported to the loading / unloading station 8 to an empty storage shelf 12 of the rack 2.

[0021] The transporting vehicle 14 is configured to be able to travel along a traveling rail 14a laid between the two racks 2. Furthermore, the transporting vehicle 14 is provided with a stacker crane 14b extending vertically upward and a slide fork 14c configured to be able to move up and down along the stacker crane 14b.

[0022] Roller conveyor 16a is provided to extend between one rack 2 and loading / unloading station 8, and is configured so that the rollers rotate to transport the loaded cases 10 from rack 2 to loading / unloading station 8. Roller conveyor 16b is provided to extend between the other rack 2 and loading / unloading station 8, and is configured so that the rollers rotate to transport the loaded cases 10 from loading / unloading station 8 to rack 2.

[0023] When a case 10 containing products is to be removed from a rack 2, the transport vehicle 14 is moved along the traveling rails 14a to a position between the racks 2. Next, the slide fork 14c is moved along the stacker crane 14b to the height of the storage shelf 12 holding the case 10 to be removed. The slide fork 14c then protrudes below the case 10 to be removed, and the case 10 is lifted from the storage shelf 12 and pulled out from the storage shelf 12. The slide fork 14c carrying the case 10 is lowered to the height of the roller conveyor 16 and further protrudes above the roller conveyor 16a, and the case 10 is placed on the roller conveyor 16a. The case 10 placed on the roller conveyor 16a is transported to the loading / unloading station 8.

[0024] Furthermore, at the receiving / retrieving station 8, once a worker has removed the required number of products from the transported case 10, the case 10 is placed on the roller conveyor 16b. The case 10 placed on the roller conveyor 16b is then transported by the roller conveyor 16b to the vicinity of the rack 2. The case 10 transported to the vicinity of the rack 2 is lifted by the slide fork 14c of the transport cart 14 and stored in the storage shelf 12 of the rack 2. Note that the storage shelf 12 to which the case 10 is returned is not necessarily the same storage shelf 12 where the case 10 was stored; as will be described later, the controller 6 assigns an appropriate storage shelf 12, thereby improving the cycle time required for receiving / retrieving processing.

[0025] 2, the controller 6 has an information input unit 6a, a storage shelf memory unit 6b, a storage / retrieval time memory unit 6c, a storage shelf selector 6d, a storage / retrieval frequency memory unit 6e, a storage / retrieval time confirmation unit 6f, and a control signal output unit 6g. In this embodiment, the controller 6 is composed of a microprocessor, a memory, an interface circuit, a transmission / reception circuit, an external storage device, and software for operating these (all not shown), and the above-mentioned functions of the controller 6 are realized.

[0026] The information input unit 6a is configured to receive a command signal from a higher-level controller 18 instructing which case 10 containing which product should be transported to the loading / unloading station 8. The storage shelf memory unit 6b is configured to store information indicating on which storage shelf 12 of the rack 2 the case 10 containing each product is stored. In addition, since the storage shelf 12 storing the case 10 containing each product changes from time to time, the information stored in the storage shelf memory unit 6b is updated each time.

[0027] The in-stock / out-stock time storage unit 6c is configured to store the time when in-stock / out processing was performed for the case 10 containing each product stored on the rack 2. In other words, the in-stock / out-stock time storage unit 6c stores when each case 10 stored on the rack 2 was transported to the in-stock / out-stock station 8 and returned to the rack 2. Note that the in-stock / out-stock time storage unit 6c may store all of the times when in-stock / out processing was performed for that product, or may store only the time when the previous in-stock / out processing was performed or the time when the product was last stored.

[0028] The storage shelf selector 6d is configured to select the storage shelf 12 that is the receiving storage shelf where the case 10, which is the outgoing cargo transported from the storage shelf 12 of the rack 2 to the receiving / outgoing station 8, should be stored again (re-stored), based on the loading / unloading time stored in the loading / unloading time memory unit 6c. In other words, the case 10 transported from the rack 2 to the receiving / unloading station 8 is not necessarily returned to the storage shelf 12 where the case 10 was stored, but is returned to an appropriate storage shelf 12 based on the previous loading / unloading time of the case 10 stored in the loading / unloading time memory unit 6c. The selection of the storage shelf 12 by the storage shelf selector 6d will be described in detail later.

[0029] The in-stock / out-stock frequency storage unit 6e is configured to store the number of in-stock / out-stock processes within a predetermined period in the past for each case 10 stored in the rack 2. For example, the in-stock / out-stock frequency storage unit 6e stores how many times in-stock / out-stock processes have been performed for each case 10 stored in the rack 2 in the most recent two weeks.

[0030] The storage / retrieval time confirmation unit 6f is configured to execute a storage / retrieval time confirmation mode. When the storage / retrieval time confirmation mode is executed, the storage / retrieval time confirmation unit 6f identifies the time when the last storage / retrieval process was performed for each case 10 stored on the rack 2 based on the data stored in the storage / retrieval time memory unit 6c. Furthermore, the storage / retrieval time confirmation unit 6f extracts retained cases 10 (retained cargo) whose last storage / retrieval process was performed a predetermined number of days or more ago. The controller 6 moves the retained cases 10 extracted by the storage / retrieval time confirmation unit 6f to a storage shelf 12 determined based on the frequency of storage / retrieval processes stored in the storage / retrieval frequency memory unit 6e. Details of the operation of the storage / retrieval time confirmation mode will be described later.

[0031] The control signal output unit 6g is configured to control the conveying device 4 based on a command signal input from the higher-level controller 18, and to convey the case 10 containing the commanded products from the storage shelf 12 of the rack 2 to the loading / unloading station 8. The control signal output unit 6g is also configured to control the conveying device 4, and to return the case 10 from which the required number of products have been picked up at the loading / unloading station 8 to the storage shelf 12 selected by the storage shelf selector 6d.

[0032] Next, the operation of the storage and retrieval system 1 according to the embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a flowchart showing the processing performed by a controller provided in the storage / retrieval system of an embodiment of the present invention when a product is retrieved. FIG. 4 is a flowchart showing the processing performed by a controller provided in the storage / retrieval system of an embodiment of the present invention when a product is retrieved. FIG. 5 is a flowchart showing the processing performed by a controller provided in the storage / retrieval system of an embodiment of the present invention in a storage / retrieval time confirmation mode. FIG. 6 is a schematic diagram showing an example of ranking of retrieval times for racks provided in the storage / retrieval system of an embodiment of the present invention. In FIG. 6, some storage shelves are given symbols such as "12a", "12b", etc. to indicate specific storage shelves among the multiple storage shelves 12.

[0033] First, when a product stored on the rack 2 is to be removed from the warehouse, the flow chart shown in FIG. 3 is executed. In step S1 of FIG. 3, the name of the product to be delivered and the number of products to be delivered are input to the information input unit 6a of the controller 6 from the higher-level controller 18.

[0034] Next, in step S2, the controller 6 references the information stored in the storage shelf memory unit 6b to identify which storage shelf 12 on the rack 2 the product to be delivered is stored in. Furthermore, once the storage shelf 12 storing the product to be delivered has been identified, in step S3, the control signal output unit 6g of the controller 6 sends a control signal to the conveyance device 4 to move the slide fork 14c of the conveyance cart 14 to the storage shelf 12 storing the product to be delivered. Next, the control signal output unit 6g controls the slide fork 14c to pull out the case 10 containing the product to be delivered from the storage shelf 12 and place the pulled case 10 onto the roller conveyor 16a. The case 10 placed on the roller conveyor 16a is transported to the loading / unloading station 8 by the roller conveyor 16a.

[0035] When a case 10 is transported to the loading / unloading station 8 as outgoing cargo, the display unit 8a (FIG. 1) of the loading / unloading station 8 displays the product name and the number of products to be unloaded, and the worker follows the display and removes the required number of products from the case 10. In addition, the date and time when a certain case 10 stored on the rack 2 is transported to the loading / unloading station 8 and the loading / unloading process is performed is stored in the loading / unloading time memory unit 6c of the controller 6.

[0036] Here, the retrieval time required to transport a case 10 containing products stored on a rack 2 from the storage shelf 12 to the loading / unloading station 8 varies depending on the storage shelf 12 on which the products are stored. That is, as shown in FIG. 1, in this embodiment, the loading / unloading station 8 is located on the left side of the rack 2. Therefore, as shown in FIG. 6, the retrieval time required to transport a case 10 from the lowest storage shelf 12a on the leftmost row of the rack 2 to the loading / unloading station 8 is shortest. On the other hand, to transport a case 10 from the topmost storage shelf 12b on the rightmost row of the rack 2 to the loading / unloading station 8, the transport vehicle 14 and the slide fork 14c must be moved a long distance, and therefore the retrieval time is longest.

[0037] Furthermore, areas A, B, and C shown in Figure 6 are obtained by ranking the retrieval times of each storage shelf 12. That is, the storage shelves 12 belonging to area A are the storage shelves 12 with the shortest retrieval times, the storage shelves 12 belonging to area B are the storage shelves 12 with relatively short retrieval times, and the storage shelves 12 belonging to area C are the storage shelves 12 with long retrieval times. Therefore, the storage shelves 12 belonging to area B have longer retrieval times than the storage shelves 12 belonging to area A, and the storage shelves 12 belonging to area C have longer retrieval times than the storage shelves 12 belonging to area B. By storing cases 10 containing products that are frequently subjected to retrieval and retrieval processing in storage shelves 12 with short retrieval times, the cycle time of retrieval and retrieval processing can be shortened and retrieval and retrieval efficiency can be improved.

[0038] Next, when a product is stored in the storage shelf 12 of the rack 2, the flow chart shown in FIG. 4 is executed. In step S11 of FIG. 4, a command to store goods is input from the higher-level controller 18 to the information input unit 6a of the controller 6. Here, there are two cases of storing goods: re-storage and new storage. Re-storage is when the required number of goods are taken out of a case 10, which is an outgoing cargo that has been removed from rack 2, at the storage / return station 8, and the case 10 is stored on the storage shelf 12 of rack 2. New storage is when a case 10 that was not stored on rack 2 is newly stored on the storage shelf 12 of rack 2.

[0039] In step S12, it is determined whether the command input in step S11 is for restocking. If it is, the process proceeds to step S14, and if it is not, the process proceeds to step S13.

[0040] Next, in step S13, the storage shelf selection unit 6d of the controller 6 selects an input storage shelf for storing the input product based on the input / output frequency data for that product stored in the input / output frequency memory unit 6e. Specifically, if the input / output frequency of the product is very high, the storage shelf selection unit 6d selects an empty storage shelf 12 (a storage shelf that does not contain a case 10) in area A of FIG. 6 as the input storage shelf so as to shorten the output time. If the input / output frequency of the product is relatively high, the storage shelf selection unit 6d selects an empty storage shelf 12 in area B of FIG. 6 as the input storage shelf. If the input / output frequency of the product is low, the storage shelf selection unit 6d selects an empty storage shelf 12 in area C of FIG. 6 as the input storage shelf. If the product to be stored has never been handled before and is being stored on rack 2 for the first time, the expected frequency of inbound and outbound shipments is input from the upper controller 18, and the area of ​​storage shelf 12 where case 10 should be stored is selected based on that frequency of inbound and outbound shipments.

[0041] Next, in step S18, a control signal is sent from the control signal output unit 6g of the controller 6 to the conveying device 4, and the case 10 containing the product to be stored is stored in the storage shelf 12 selected by the storage shelf selection unit 6d. This completes the storage process for one product.

[0042] On the other hand, if it is determined in step S12 that the product to be stocked is a restocked product, the process proceeds to step S14. In step S14, the storage shelf selection unit 6d refers to the data on the storage and retrieval times stored in the storage and retrieval time memory unit 6c and determines whether or not a storage and retrieval process has been performed on the product within the most recent predetermined time period. That is, the storage shelf selection unit 6d determines whether or not a storage and retrieval process has been performed on the case 10, which is an outgoing item transported from the rack 2 to the storage and retrieval station 8, within the most recent predetermined time period. In this embodiment, the storage shelf selection unit 6d determines whether or not a storage and retrieval process has been performed on the case 10 transported from the rack 2 to the storage and retrieval station 8 within the most recent 24 hours (one day). Note that in this embodiment, the input storage shelf is selected based on whether or not a storage and retrieval process has been performed within the last 24 hours. However, this period may be a variable period; for example, the present invention may be configured so that the period is changed based on the average storage period of the items stored on the rack.

[0043] If no receiving / retrieving process has been performed on the case 10 that has been delivered from the rack 2 to the receiving / retrieving station 8 within the most recent 24 hours, the process proceeds to step S13. In step S13, as described above, the storage shelf selection unit 6d selects an receiving storage shelf for storing the incoming goods based on the receiving / retrieving frequency data stored in the receiving / retrieving frequency memory unit 6e, and then in step S18, the case 10 is stored in the selected receiving storage shelf. In this way, if the case 10 that is the outgoing goods that has been transported from the rack 2 to the receiving / retrieving station 8 has not been subjected to receiving / retrieving process within the most recent predetermined time (24 hours), the storage shelf selection unit 6d selects an receiving storage shelf based on the frequency of receiving / retrieving process stored in the receiving / retrieving frequency memory unit 6e.

[0044] On the other hand, if it is determined in step S14 that a storage / retrieval process has been performed within the past 24 hours for the case 10 that was retrieved from the rack 2 to the storage / retrieval station 8, the process proceeds to step S15. In step S15, a search is made for an available storage shelf 12 among the storage shelves 12 in area A in FIG. 6.

[0045] Next, in step S16, it is determined whether or not there is an empty storage shelf 12 in area A, and if there is an empty storage shelf 12, the process proceeds to step S18. In step S18, an empty storage shelf 12 in area A is selected by the storage shelf selection unit 6d, and the conveying device 4 stores (re-stores) the case 10 in the selected storage shelf 12. In this way, if the released case 10 is a case 10 that has been subjected to an in / out processing within the last 24 hours, there is a high probability that an in / out processing will be performed on that case 10 again, so the case 10 is re-stored in an empty storage shelf 12 in area A so as to shorten the retrieval time required to transport it from the storage shelf 12 to the in / out station 8.

[0046] 6, if case 10 stored on storage shelf 12c of rack 2 is released and an inbound / outbound process has been performed on this case 10 within the past 24 hours, a search is made for an available storage shelf 12 in area A. Furthermore, if storage shelf 12d of rack 2 in area A is available, case 10 is re-stored on storage shelf 12d. As a result, case 10 stored on storage shelf 12c in area C of rack 2 is re-stored on storage shelf 12d in area A, and therefore the time required to transport case 10 from storage shelf 12 to inbound / outbound station 8 is shortened in the next inbound / outbound process.

[0047] In this way, in the receiving / retrieving system 1 of this embodiment, a storage shelf 12 is selected based on the time of the previous receiving / retrieving process for the retrieved case 10, and a storage shelf 12 can be allocated in response to sudden changes in the frequency of receiving / retrieving. In contrast, since the frequency of receiving / retrieving is calculated based on the number of times receiving / retrieving occurs in a predetermined period, if a storage shelf 12 is selected based on the frequency of receiving / retrieving, it takes time for the most recent receiving / retrieving of the case 10 to be fully reflected in the frequency data, making it difficult to respond to sudden changes in the frequency of receiving / retrieving.

[0048] Furthermore, if the case 10 retrieved from rack 2 was stored on a storage shelf 12 in area A of rack 2, even if a storage / retrieval process was performed on the case 10 within the most recent 24 hours, a search for the storage shelf 12 is not performed, and the case 10 is re-stored in the original storage shelf 12. That is, in this embodiment, if the case 10 retrieved from rack 2 was retrieved within the most recent predetermined time, it is re-stored in the storage shelf 12 with the shorter retrieval time, as a general rule. However, if the case 10 was already stored on a storage shelf 12 with a shorter retrieval time, it is re-stored in the original storage shelf 12, and the retrieval time does not change. In this way, if the case 10 retrieved from rack 2 was retrieved within the most recent predetermined time, the retrieval time required to transport it from the storage shelf 12 to the retrieval / retrieval station 8 is equal to or shorter than the retrieval time from the storage shelf 12 where the case 10 was stored.

[0049] On the other hand, if it is determined in step S16 that there is no vacant storage shelf 12 in area A, the process proceeds to step S17. In step S17, a vacant storage shelf 12 in area B is selected by the storage shelf selection unit 6d, and in step S18, the transport device 4 stores (restocks) the case 10 on the selected storage shelf 12.

[0050] For example, in the example shown in FIG. 6, if a case 10 stored on storage shelf 12c of rack 2 is retrieved and an inbound / outbound process has been performed on this case 10 within the past 24 hours, an available storage shelf 12 in area A is searched for in step S15. Furthermore, if an available storage shelf 12 is not present in area A, an available storage shelf 12 in area B is searched for in step S17. For example, if storage shelf 12e is available, the case 10 is re-stored on storage shelf 12e. As a result, the case 10 stored on storage shelf 12c in area C of rack 2 is re-stored on storage shelf 12e in area B, and therefore the time required to transport the case 10 from the storage shelf 12 to the inbound / outbound station 8 is shortened in the next inbound / outbound process.

[0051] On the other hand, if the case 10 retrieved from rack 2 was stored on storage shelf 12 in area B of rack 2, the search for storage shelf 12 in step S17 is not performed even if an in / out process has been performed on that case 10 within the most recent 24 hours, and the case 10 is re-stored to its original storage shelf 12. Therefore, in this case, the outgoing time required to transport the case 10 from storage shelf 12 to in / out station 8 does not change. Therefore, if the case 10 retrieved from rack 2 was subjected to an in / out process within the most recent predetermined time, the outgoing time required to transport the case 10 from storage shelf 12 to in / out station 8 will be less than or equal to the outgoing time from the storage shelf 12 where the case 10 was stored.

[0052] As described above, in this embodiment, a storage shelf 12 is selected based on whether or not a storage / retrieval process has been performed on the case 10 to be restocked within the past 24 hours. However, as a modified example, in addition to the threshold of "within 24 hours," the present invention can also be configured so that, for example, it is determined whether or not a storage / retrieval process has been performed within the past 48 hours, and if a storage / retrieval process has been performed during this time, an available storage shelf 12 in area B is searched for. In this way, multiple thresholds can be set, and the present invention can be configured so that the more recently a storage / retrieval process has been performed, the shorter the storage shelf 12 with a shorter retrieval time is selected.

[0053] Next, the operation in the warehouse entry / exit timing confirmation mode will be described with reference to FIG. The storage / retrieval time confirmation mode is a process executed by the storage / retrieval time confirmation unit 6f of the controller 6, and Fig. 5 is a flowchart showing the processing procedure in the storage / retrieval time confirmation mode. The process in the flowchart shown in Fig. 5 is executed once every predetermined number of days, for example, about once every 30 days. The present invention can also be configured so that the process in the flowchart shown in Fig. 5 is executed at any time based on the operation of the manager of the storage / retrieval system 1, etc.

[0054] First, in step S21 of Fig. 5, the time when the previous loading / unloading process was performed for each case 10 stored on rack 2 is identified by the loading / unloading time confirmation unit 6f of controller 6 based on the data stored in the loading / unloading time memory unit 6c. In this embodiment, the time when the previous loading / unloading process was performed is identified for each case 10 stored in the storage shelf 12 with the shortest unloading time. That is, starting from the case 10 stored on the lower left storage shelf 12a in area A in Fig. 6, the time when the previous loading / unloading process was performed is identified for each case 10, from left to right and from the bottom shelf to the top shelf.

[0055] Next, in step S22, it is determined whether the time when the previous inbound / outbound processing identified in step S21 was performed is a predetermined number of days or more ago. In this embodiment, it is determined whether the time when the previous inbound / outbound processing was performed is 30 days or more ago. If it is less than 30 days ago, the process in the flowchart returns to step S21, and if it is 30 days or more ago, the process proceeds to step S23. If it returns to step S21, the time when the previous inbound / outbound processing was performed for the next case 10 is identified. That is, in the example shown in FIG. 6, after the case 10 stored on storage shelf 12a of rack 2, the time when the previous inbound / outbound processing was performed is identified for the case 10 stored on the storage shelf 12 immediately to the right of storage shelf 12a.

[0056] On the other hand, if it is determined in step S22 that the time when the previous loading / unloading process identified in step S21 was performed is more than a predetermined number of days ago (30 days in this embodiment), the process proceeds to step S23. That is, in step S22, the loading / unloading time confirmation unit 6f extracts cases 10 that are held up cargo and whose previous loading / unloading process was performed more than a predetermined number of days ago.

[0057] Furthermore, in step S23, the case 10 that is the held-up cargo is moved to a storage shelf 12 in an area determined based on the data on the input / output frequency of the goods stored in the case 10. That is, the control signal output unit 6g of the controller 6 sends a control signal to the conveying device 4 to move the case 10 extracted as the held-up cargo to an empty storage shelf 12 in the area determined based on the data on the input / output frequency. For example, in the example shown in FIG. 6, if the last input / output process for a case 10 stored on storage shelf 12d in area A of rack 2 was performed 30 days or more ago, the case 10 is moved to an empty storage shelf 12c in area C determined based on the data on the input / output frequency.

[0058] In this way, if a case 10 with a very low frequency of entry and exit, whose last entry and exit processing was more than a predetermined number of days ago, occupies a storage shelf 12 in area A with a short exit time, it becomes impossible to store a case 10 with a high frequency of entry and exit on a storage shelf 12 with a short exit time. For this reason, in the entry and exit time confirmation mode, a case 10 (staying cargo) whose last entry and exit processing was more than a predetermined number of days ago is extracted and moved to a storage shelf 12 determined based on the entry and exit frequency data. This frees up a storage shelf 12 with a short exit time, making it possible to store a case 10 with a high frequency of entry and exit there.

[0059] Next, in step S24, it is determined whether confirmation of the entry / exit times has been completed for all cases 10 for which entry / exit times are to be confirmed. If confirmation has been completed for all cases 10 for which entry / exit times are to be confirmed, one iteration of the processing of the flowchart shown in FIG. 5 is completed. If confirmation has not been completed for all cases 10, the process returns to step S21, and confirmation of the entry / exit times is performed for the next case 10. In this embodiment, cases 10 stored in storage shelves 12 belonging to areas A and B of rack 2 in FIG. 6 are subject to confirmation, and cases 10 identified as held-up goods are moved to storage shelves 12 determined based on data on entry / exit frequency. As a variant, the present invention can also be configured so that cases 10 (held-up goods) whose last entry / exit processing was more than 30 days ago are moved to vacant storage shelves 12 with a longer retrieval time (for example, storage shelves 12 in area C).

[0060] Furthermore, in this embodiment, a check is performed on all target cases 10. However, as a modified example, the present invention can be configured to extract cases 10 stored on storage shelves 12 in an area with shorter entry / exit times than the area of ​​the storage shelves 12 determined based on data on the entry / exit frequency of the products stored in the cases 10, and to check the extracted cases 10. That is, cases 10 that have undergone entry / exit processing within the last 24 hours are moved to storage shelves 12 in an area with shorter entry / exit times (steps S14 to S15 in FIG. 4), but a check can also be performed on cases 10 whose storage shelves 12 have been changed in this way.

[0061] According to the storage / retrieval system 1 of the embodiment of the present invention, if the retrieved case 10 has undergone storage / retrieval processing within the most recent predetermined time (24 hours) (steps S14 to S15 in FIG. 4), the storage shelf 12 to which the retrieval case 10 is to be stored is selected so that the retrieval time is equal to or shorter than the retrieval time of the storage shelf 12 from which the retrieving case 10 is stored. Therefore, the case 10 that has undergone storage / retrieval processing most recently will have a shorter retrieval time than the storage shelf 12 from which it was previously stored, or will be stored in a storage shelf 12 with the same retrieval time as the storage shelf 12 from which it was previously stored. As a result, even if the frequency of storage / retrieval for a certain case 10 suddenly increases, the case 10 can be moved to a storage shelf 12 with a shorter retrieval time in a short period of time, thereby sufficiently shortening the storage / retrieval time.

[0062] Furthermore, according to the warehousing / retrieval system 1 of this embodiment, if the retrieved case 10 has not undergone warehousing / retrieval processing within the most recent predetermined time period (steps S14 to S13 in FIG. 4), the storage shelf 12 to which the case 10 is to be stored is selected based on the frequency of warehousing / retrieval processing. Therefore, even for a case 10 for which warehousing / retrieval processing has not been performed recently, an appropriate storage shelf 12 can be assigned according to the frequency of warehousing / retrieval processing, thereby improving the overall efficiency of warehousing / retrieval processing.

[0063] Furthermore, according to the storage / retrieval system 1 of this embodiment, retained cases 10 whose last storage / retrieval process was performed a predetermined number of days or more ago are extracted (steps S22 to S23 in FIG. 5), and the extracted cases 10 are moved to storage shelves 12 determined based on data on storage / retrieval frequency (step S23 in FIG. 5). This makes it possible to prevent cases 10 that are infrequently subjected to storage / retrieval processes from continuing to occupy storage shelves 12 with short retrieval times, and allows for efficient use of storage shelves 12 with short retrieval times.

[0064] Although the embodiments of the present invention have been described above, various modifications can be made to the above-described embodiments. In particular, in the above-described embodiments, the present invention is applied to a storage and retrieval system that transports luggage using a single stacker crane and a roller conveyor. However, the present invention can also be applied to a storage and retrieval system using a shuttle cart for each tier of racks, in which a shuttle cart is provided for each tier of racks. In this case, the storage shelf that is horizontally closer to the storage and retrieval station and closer to the tier where the storage and retrieval station is provided has a shorter retrieval time. However, it is preferable to distribute luggage that is frequently retrieved and retrieved across storage shelves on each tier.

[0065] The present invention can also be applied to a large-scale system in which cargo stored in multiple automated warehouses is transported by rail-guided vehicles. In this case, the storage shelf with the shortest retrieval time in each automated warehouse will also be the storage shelf with the shortest retrieval time for the entire system. However, it is preferable to distribute cargo that is frequently received and retrieved among multiple automated warehouses. [Explanation of symbols]

[0066] 1. Storage and retrieval system 2 racks 4. Conveyor equipment 6 Controller 6a Information input section 6b Storage shelf storage section 6c Warehousing / discharging time storage section 6d Storage shelf selection section 6e Input / output frequency storage section 6f Input / output timing confirmation section 6g Control signal output section 8. Loading and unloading station 8a Display section 10 cases (luggage) 12 Storage Shelves 14 Transport cart 14a Running rail 14b Stacker crane 14c sliding fork 16a Roller conveyor 16b Roller conveyor 18 Upper Controller

Claims

1. A storage and retrieval system for storing and retrieving luggage, a rack having a plurality of storage shelves for storing luggage; a transport device that performs a loading / unloading process of transporting the cargo stored in the rack from the storage shelf of the rack to a loading / unloading station and returning the cargo transported to the loading / unloading station to an empty storage shelf of the rack; a controller for controlling the transport device, The above controller is a storage / retrieval time storage unit that stores the storage / retrieval time when the storage / retrieval process was performed for each piece of luggage stored in the rack; a storage shelf selection unit that selects an incoming storage shelf to which the outgoing goods transported from the storage shelf of the rack to the incoming / outgoing station should be re-stored, based on the incoming / outgoing time stored in the incoming / outgoing time storage unit; a storage / retrieval frequency storage unit that stores the frequency of storage / retrieval processing within a predetermined period in the past for each piece of luggage stored in the rack; Equipped with The storage shelves in the racks are divided into multiple rank areas according to the time required for retrieval. When the outgoing goods transported from the rack to the loading / unloading station have undergone loading / unloading processing within the most recent predetermined time, the storage shelf selection unit selects, when re-loading the outgoing goods, an incoming storage shelf in an area ranked so as to have the shortest retrieval time required for transporting the outgoing goods from the storage shelf to the loading / unloading station; a storage / retrieval system characterized in that, when the outgoing luggage transported from the rack to the inbound / outbound station has not undergone inbound / outbound processing within the most recent predetermined time, the storage shelf selection unit selects an inbound storage shelf within an area of ​​a rank set according to the frequency of inbound / outbound processing stored in the inbound / outbound frequency memory unit when re-entering the outgoing luggage.

2. 2. The inventory system of claim 1, wherein the controller further comprises an inventory / shipping time confirmation unit that executes an inventory / shipping time confirmation mode, and when the inventory / shipping time confirmation mode is executed, the inventory / shipping time confirmation unit determines the time of the last inventory / shipping process for each item stored on the rack based on the data stored in the inventory / shipping time memory unit, and extracts any remaining items whose last inventory / shipping process was more than a predetermined number of days ago, and the controller moves the extracted remaining items to a storage shelf determined based on the frequency of inventory / shipping processes stored in the inventory / shipping frequency memory unit.

Images