Article conveying equipment

Abstract

In a configuration where the elevating and conveying device includes two elevating devices, namely an upper elevating device and a lower elevating device, when a plurality of articles are conveyed from the hierarchical conveying device to the unloading device by the elevating and conveying device, it is desired to realize a technology that can easily improve the conveying efficiency of the articles by the elevating and conveying device. 【Solution means】The article conveying facility includes a hierarchical conveying device 4 arranged in multiple levels, an elevating and conveying device for conveying the article W in the vertical direction Z, and an unloading device. The elevating and conveying device includes an upper elevating device 6U and a lower elevating device 6L. As a selection process for selecting the article W received by each of the upper elevating device 6U and the lower elevating device 6L, the control system executes a first selection process such that the lowest-level Z1 hierarchical conveying device 4 among the hierarchical conveying devices 4 where the article W received by the upper elevating device 6U is arranged is above the highest-level Z2 hierarchical conveying device 4 among the hierarchical conveying devices 4 where the article W received by the lower elevating device 6L is arranged, that is, at Z2.

Description

Technical Field

[0001] The present invention relates to an article conveying facility including a multi-layer conveying device arranged in a plurality of layers so as to be arranged vertically, a lifting and conveying device that conveys an article received from the multi-layer conveying device in the vertical direction, and a discharging device that discharges the article received from the lifting and conveying device.

Background Art

[0002] An example of the above-described article conveying facility is disclosed in Japanese Patent Application Laid-Open No. 2022-94209 (Patent Document 1). Hereinafter, in the description of this background art, the reference numerals in Patent Document 1 are cited in parentheses. Patent Document 1 discloses an automatic warehouse (100) including an outbound conveyor (25) as a multi-layer conveying device, an outbound lifting device (13) as a lifting and conveying device, and an outbound station (9) as a discharging device. The outbound lifting device (13) includes a lifting platform (63) on which a load (W) as an article is placed, and a lifting mechanism (65) that raises and lowers the lifting platform (63).

[0003] When discharging the load (W) from the automatic warehouse (100), the outbound lifting device (13) raises and lowers the lifting platform (63) to the shelf level (21) where the load (W) to be discharged is located, and receives the load (W) from the outbound conveyor (25) arranged on the shelf level (21). Then, the outbound lifting device (13) raises and lowers the lifting platform (63) to the position of the outbound station (9), and delivers the load (W) to the outbound station (9). In the automatic warehouse (100) of Patent Document 1, when the loads (W) included in one order are complete, the plurality of loads (W) included in the order are discharged from the automatic warehouse (100). And in the automatic warehouse (100) of Patent Document 1, at the time of receiving the load (W), by dispersing the plurality of loads (W) included in one order to a plurality of shelf levels (21) below the upper limit value and determining the storage position, the discharging efficiency is improved.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, it is conceivable that the lifting and conveying device has a configuration including two lifting devices, an upper lifting device and a lower lifting device. Even in such a configuration, when a plurality of articles (in Patent Document 1, a plurality of packages included in one order) are conveyed by the lifting and conveying device from the hierarchical conveying device to the unloading device, it is desirable to improve the conveying efficiency of the articles by the lifting and conveying device (in Patent Document 1, the unloading efficiency). However, Patent Document 1 does not describe a configuration in which the lifting and conveying device includes two lifting devices, an upper lifting device and a lower lifting device.

[0006] Therefore, in a configuration in which the lifting and conveying device includes two lifting devices, an upper lifting device and a lower lifting device, when a plurality of articles are conveyed by the lifting and conveying device from the hierarchical conveying device to the unloading device, it is desired to realize a technology that can easily improve the conveying efficiency of the articles by the lifting and conveying device.

Means for Solving the Problems

[0007] The article conveying facility according to the present disclosure includes a multi-layer conveying device arranged in multiple layers so as to be arranged vertically, a lifting and lowering conveying device that conveys the article received from the multi-layer conveying device in the vertical direction, an unloading device that unloads the article received from the lifting and lowering conveying device, and a control system that controls the multi-layer conveying device and the lifting and lowering conveying device. The lifting and lowering conveying device includes an upper lifting and lowering device that moves in the vertical direction along a lifting and lowering path, and a lower lifting and lowering device that moves in the vertical direction along the lifting and lowering path below the upper lifting and lowering device. The upper lifting and lowering device and the lower lifting and lowering device are each configured to be able to hold a plurality of the articles. The control system executes a first selection process as a selection process for selecting the articles received by each of the upper lifting and lowering device and the lower lifting and lowering device, such that the lowermost multi-layer conveying device among the multi-layer conveying devices where the articles received by the upper lifting and lowering device are arranged is above the uppermost multi-layer conveying device among the multi-layer conveying devices where the articles received by the lower lifting and lowering device are arranged.

[0008] According to this configuration, when a plurality of articles are conveyed from the multi-layer conveying device to the unloading device by the lifting and lowering conveying device, by executing the first selection process, the vertical range in which the upper lifting and lowering device receives articles from the multi-layer conveying device and the vertical range in which the lower lifting and lowering device receives articles from the multi-layer conveying device can be made not to overlap. Thereby, it is easy to overlap the execution period of the receiving operation in which the upper lifting and lowering device receives articles from the multi-layer conveying device and the execution period of the receiving operation in which the lower lifting and lowering device receives articles from the multi-layer conveying device. Therefore, it is easy to improve the conveying efficiency of the articles by the lifting and lowering conveying device.

[0009] Further features and advantages of the article conveying facility will become clear from the following description of the embodiments described with reference to the drawings.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] An embodiment of the article conveying equipment will be described with reference to the drawings. As shown by an example in FIGS. 1 and 2, the article conveying equipment 100 includes a hierarchical conveying device 4, a lifting conveying device 6, an unloading device 2, and a control system C. The article conveying equipment 100 further includes a storage shelf 1, a loading device 3, and a transport vehicle 5. Various technical features of the control system C described below are also applicable to an article conveying method in the article conveying equipment and an article conveying program (a program for causing a computer to function as the control system C) for controlling the article conveying equipment. Such a method and program, and further, a storage medium (for example, a computer-readable recording medium such as a flash memory of an optical disk) in which such a program is stored are also disclosed by this specification.

[0012] As shown in FIG. 2, the control system C controls the hierarchical conveying device 4 and the lifting conveying device 6. The control system C further controls the unloading device 2, the loading device 3, and the transport vehicle 5. The control system C controls the operation of the device to be controlled by controlling the drive of a drive power source (for example, an electric motor) provided in the device to be controlled. Each function of the control system C is realized, for example, by cooperation between hardware such as an arithmetic processing unit and a program executed on the hardware. The control system C may be composed not of a single piece of hardware but of a set of a plurality of pieces of hardware (a plurality of separate pieces of hardware) capable of communicating with each other. Also, a device to be controlled by the control system C (for example, a controller included in the device) may constitute at least a part of the control system C.

[0013] As shown in FIG. 1, taking two horizontal directions orthogonal to each other as the X direction and the Y direction, the storage shelf 1 is arranged such that the shelf width direction is along the X direction and the shelf depth direction is along the Y direction. The transport vehicle 5 travels along the X direction to transport the article W. In the example shown in FIG. 1, a pair of storage shelves 1 are arranged to face each other in the Y direction, and the transport vehicle 5 travels along the X direction between the pair of storage shelves 1 in the Y direction. In the example shown in FIG. 1, the transport vehicle 5 is configured to transport the articles W one by one, but the transport vehicle 5 can also be configured to transport a plurality of articles W (for example, two articles W) together. Further, the transport vehicle 5 can be configured to include two carriages, a first carriage that travels along the X direction and a second carriage that can be mounted on the first carriage and separates from the first carriage to travel along the Y direction to transport the article W.

[0014] The storage shelf 1 includes a shelf portion 10 that supports the article W, and the article W is stored in the storage shelf 1 while being supported by the shelf portion 10. The shelf portion 10 is arranged in a plurality of layers so as to be arranged in the Z direction, which is the vertical direction, and the storage shelf 1 is configured to be able to store the article W in each of the plurality of layers (tiers). The article W is, for example, a container (such as a container or a cardboard box) that stores a load (such as a commodity). The travel path of the transport vehicle 5 is formed corresponding to each of the shelf portions 10 arranged in a plurality of layers. Here, the travel path of the transport vehicle 5 is formed by a pair of rails 50 arranged at intervals in the Y direction.

[0015] Although only some of the articles W are shown in FIG. 1, the shelf portion 10 is configured to be able to support the article W at a plurality of positions in the X direction. That is, the shelf portion 10 is configured to be able to support a plurality of articles W arranged side by side in the X direction. The shelf portion 10 may be configured to be able to support a plurality of articles W (for example, two articles W) arranged side by side in the Y direction at each position in the X direction.

[0016] As shown in FIG. 1, the hierarchical conveyor device 4 is arranged in a plurality of levels so as to be aligned in the Z direction. In the example shown in FIG. 1, the hierarchical conveyor device 4 is provided corresponding to each of the shelves 10 arranged in a plurality of levels. Taking the group of hierarchical conveyor devices 4 arranged in a plurality of levels as a hierarchical conveyor device group, in the example shown in FIG. 1, a pair of hierarchical conveyor device groups are arranged separately on both sides in the Y direction with the traveling path of the transport vehicle 5 interposed therebetween. FIG. 1 shows the shelves 10 arranged in six levels in the storage shelf 1 and the hierarchical conveyor devices 4 arranged in six levels. Further, FIG. 1 shows the transport vehicle 5 arranged in the uppermost level among the six levels.

[0017] The conveyance of the article W between the shelf 10 and the hierarchical conveyor device 4 arranged in the same level is performed by the transport vehicle 5. The transfer of the article W between the transport vehicle 5 and the transfer target location (shelf 10 or hierarchical conveyor device 4) of the article W is performed, for example, by a transfer device provided on the transport vehicle 5.

[0018] The hierarchical conveyor device 4 conveys the article W in the horizontal direction (here, the X direction). The hierarchical conveyor device 4 includes a conveyor (such as a roller conveyor or a belt conveyor, the same applies hereinafter) that conveys the article W in the X direction. The hierarchical conveyor device 4 delivers the article W to the lifting and conveying device 6 or receives the article W from the lifting and conveying device 6 by the conveying operation of the article W by the conveyor (here, in cooperation with the conveying operation of the article W by the conveyor provided in the lifting and conveying device 6). Further, the hierarchical conveyor device 4 is configured to be able to support a plurality of articles W side by side in the horizontal direction (here, the X direction). In the example shown in FIG. 1, the hierarchical conveyor device 4 is configured to be able to support three articles W side by side in the X direction.

[0019] The lifting and conveying device 6 conveys the article W in the Z direction. In the example shown in FIG. 1, a pair of lifting and conveying devices 6 are provided so as to be aligned in the Y direction. The lifting and conveying device 6 conveys the article W received from the hierarchical conveyor device 4 in the Z direction. Further, the lifting and conveying device 6 conveys the article W received from the loading device 3 in the Z direction.

[0020] The lifting and conveying device 6 includes an upper lifting device 6U that moves in the Z direction along a lifting path 60, and a lower lifting device 6L that moves in the Z direction along the lifting path 60 at a position Z1 below the upper lifting device 6U. The lifting path 60 is formed by, for example, a mast or a rail. The upper lifting device 6U and the lower lifting device 6L move in the Z direction along the same lifting path 60. Therefore, the upper lifting device 6U can move in the Z direction within a range with a lower limit at a position where it interferes with the lower lifting device 6L, and the lower lifting device 6L can move in the Z direction within a range with an upper limit at a position where it interferes with the upper lifting device 6U.

[0021] The transfer of the article W between the upper lifting device 6U and the transfer target location of the article W (the hierarchical conveying device 4, the unloading device 2, or the loading device 3, the same hereinafter) is performed in a state where the upper lifting device 6U moves in the Z direction to a height corresponding to the transfer target location and is arranged at that height. The transfer of the article W between the lower lifting device 6L and the transfer target location of the article W is performed in a state where the lower lifting device 6L moves in the Z direction to a height corresponding to the transfer target location and is arranged at that height. Each of the upper lifting device 6U and the lower lifting device 6L is provided with a conveyor for conveying the article W in the horizontal direction (here, the X direction), and by the conveying operation of the article W by the conveyor (here, in cooperation with the conveying operation of the article W by the conveyor provided at the transfer target location), the article W is received from the transfer target location, or the article W is delivered to the transfer target location.

[0022] The upper lifting device 6U and the lower lifting device 6L are each configured to be able to hold a plurality of articles W. The plurality of articles W are held so as to be arranged in the horizontal direction (here, the X direction) in each of the upper lifting device 6U and the lower lifting device 6L. As shown in FIG. 1, the upper lifting device 6U and the lower lifting device 6L are configured to be able to hold the same number of articles W as each other. Specifically, the upper lifting device 6U and the lower lifting device 6L are each configured to be able to hold two articles W.

[0023] Each of the upper lifting device 6U and the lower lifting device 6L holds one or more articles W received from the hierarchical conveyor device 4 or the loading device 3. When receiving a plurality of articles W (here, two articles W, the same applies hereinafter) from the hierarchical conveyor device 4, each of the upper lifting device 6U and the lower lifting device 6L may receive a plurality of articles W from one hierarchical conveyor device 4 or may receive a total of a plurality of articles W from a plurality of hierarchical conveyor devices 4. Each of the upper lifting device 6U and the lower lifting device 6L is controlled by the control system C so as to receive the article W selected by the selection process described later.

[0024] The unloading device 2 unloads the article W received from the lifting and conveying device 6 to an outbound line or the like. The loading device 3 delivers the article W carried in from an inbound line or the like to the lifting and conveying device 6. The unloading device 2 and the loading device 3 are each provided with a conveyor for conveying the article W in the horizontal direction (here, the X direction).

[0025] Taking one side in the X direction as the X-direction first side X1 and the other side in the X direction as the X-direction second side X2, in the example shown in FIG. 1, the pair of lifting and conveying devices 6 are arranged on the X-direction first side X1 with respect to the storage shelf 1. Also, taking one side in the Y direction as the Y-direction first side Y1 and the other side in the Y direction as the Y-direction second side Y2, in the example shown in FIG. 1, among the pair of lifting and conveying devices 6, the lifting and conveying device 6 arranged on the Y-direction first side Y1 is used for outbound, and the lifting and conveying device 6 arranged on the Y-direction second side Y2 is used for inbound. Also, among the pair of hierarchical conveyor device groups (groups of hierarchical conveyor devices 4 arranged in multiple layers), the hierarchical conveyor device group arranged on the Y-direction first side Y1 is used for outbound, and the hierarchical conveyor device group arranged on the Y-direction second side Y2 is used for inbound.

[0026] The lifting and conveying device 6 for shipping is arranged at a position in the Y direction where it can receive the article W from the group of hierarchical conveying devices for shipping, and the lifting and conveying device 6 for warehousing is arranged at a position in the Y direction where it can deliver the article W to the group of hierarchical conveying devices for warehousing. Further, the unloading device 2 is arranged at a position in the Y direction where it can receive the article W from the lifting and conveying device 6 for shipping, and the loading device 3 is arranged at a position in the Y direction where it can deliver the article W to the lifting and conveying device 6 for warehousing. Note that, different from the example shown in FIG. 1, the loading device 3 may be arranged on the second side X2 in the X direction with respect to the storage shelf 1, and the lifting and conveying device 6 arranged on the second side X2 in the X direction with respect to the storage shelf 1 may be used as the one for warehousing.

[0027] The article W to be warehoused in the article conveying facility 100 (specifically, the storage shelf 1) is delivered from the loading device 3 to the lifting and conveying device 6 for warehousing. The lifting and conveying device 6 (specifically, each of the upper lifting device 6U and the lower lifting device 6L) conveys the article W received from the loading device 3 in the Z direction and delivers it to the hierarchical conveying device 4 that constitutes the group of hierarchical conveying devices for warehousing and is arranged on the same floor as the shelf portion 10 where the article W is to be stored. Then, the article W delivered to the hierarchical conveying device 4 is conveyed by the transport cart 5 to the storage position of the article W in the shelf portion 10 and stored at the storage position.

[0028] The article W to be shipped from the article conveying facility 100 (specifically, the storage shelf 1) is conveyed by the transport cart 5 from the storage position of the article W in the shelf portion 10 to the hierarchical conveying device 4 that constitutes the group of hierarchical conveying devices for shipping. The hierarchical conveying device 4 delivers the article W received from the transport cart 5 to the lifting and conveying device 6 for shipping. The lifting and conveying device 6 (specifically, each of the upper lifting device 6U and the lower lifting device 6L) conveys the article W received from the hierarchical conveying device 4 in the Z direction and delivers it to the unloading device 2.

[0029] As shown in FIG. 5, the unloading device 2 is configured to receive the article W from each of the upper lifting device 6U and the lower lifting device 6L at a predetermined position in the Z direction. As shown in FIGS. 1 and 5, the position in the Z direction where the unloading device 2 receives the article W from each of the upper lifting device 6U and the lower lifting device 6L is biased to the lower side Z1, which is one side in the Z direction, within the entire Z direction of the lifting path 60. In the present embodiment, the lower side Z1 corresponds to the "first side in the vertical direction".

[0030] Hereinafter, the shipping process of the article W by the control system C will be specifically described. Therefore, the hierarchical transfer device 4 in the following description means the hierarchical transfer device 4 used for shipping, and the lifting transfer device 6 means the lifting transfer device 6 used for shipping.

[0031] Taking a series of shipping operations in which the lifting transfer device 6 receives the article W from the hierarchical transfer device 4 and the lifting transfer device 6 unloads the article W to the unloading device 2 as one cycle, the control system C repeatedly executes this cycle to perform the shipping process of the article W. In each cycle, the same number of articles W (here, four articles W) as the maximum number of articles W that the upper lifting device 6U and the lower lifting device 6L can hold are the targets of the shipping process. In each cycle, the article W selected by the selection process described later is the target of the shipping process. As described below, if the lifting transfer device 6 cannot receive the same number of articles W as the maximum number in each cycle from the hierarchical transfer device 4, the control system C sets the articles W that cannot be received in that cycle as the shipping targets in the next cycle. In each cycle, the operation of each of the upper lifting device 6U and the lower lifting device 6L is controlled so that the execution period of the receiving operation in which the upper lifting device 6U receives the article W from the hierarchical transfer device 4 and the execution period of the receiving operation in which the lower lifting device 6L receives the article W from the hierarchical transfer device 4 overlap as much as possible on the condition that the upper lifting device 6U and the lower lifting device 6L do not interfere with each other.

[0032] When the control system C conveys a plurality of articles W from the hierarchical conveyor 4 to the unloading device 2 by the lifting and conveying device 6, it executes a selection process for selecting the articles W received by each of the upper lifting device 6U and the lower lifting device 6L. The control system C executes a first selection process as the selection process.

[0033] The first selection process is a selection process in which the lowermost Z1 hierarchical conveyor 4 among the hierarchical conveyors 4 where the article W received by the upper lifting device 6U is placed is above the uppermost Z2 hierarchical conveyor 4 among the hierarchical conveyors 4 where the article W received by the lower lifting device 6L is placed, i.e., Z2. When all of the articles W received by the upper lifting device 6U are placed on one hierarchical conveyor 4, that hierarchical conveyor 4 becomes the lowermost Z1 hierarchical conveyor 4 as described above. Also, when all of the articles W received by the lower lifting device 6L are placed on one hierarchical conveyor 4, that hierarchical conveyor 4 becomes the uppermost Z2 hierarchical conveyor 4 as described above. In the first selection process, basically, the articles W received by each of the upper lifting device 6U and the lower lifting device 6L are selected so that the upper lifting device 6U and the lower lifting device 6L receive the maximum number of articles W that they can hold (here, a total of four articles W are received).

[0034] Figure 4 shows how the article W selected by the first selection process is received by each of the upper lifting device 6U and the lower lifting device 6L. In FIGS. 3 to 17 including FIG. 4, the numbers representing the delivery order described later are shown inside the square representing the article W. Hereinafter, the article W with the delivery order of the Nth is described as article W[N]. In FIG. 4, articles W[1] and W[2] are selected as the articles W received by the upper lifting device 6U, and articles W[3] and W[4] are selected as the articles W received by the lower lifting device 6L. In this case, the range in the Z direction (hereinafter referred to as the "first range") in which the upper lifting device 6U receives the article W from the hierarchical conveyor 4 is the range in the Z direction between the hierarchical conveyor 4 where the article W[1] is arranged and the hierarchical conveyor 4 where the article W[2] is arranged. Further, the range in the Z direction (hereinafter referred to as the "second range") in which the lower lifting device 6L receives the article W from the hierarchical conveyor 4 is the range in the Z direction between the hierarchical conveyor 4 where the article W[3] is arranged and the hierarchical conveyor 4 where the article W[4] is arranged. In the first selection process, the first range and the second range can be made not to overlap. In FIGS. 4 and FIGS. 5 to 7 and FIGS. 14 to 17 referred to later, the figure shown in (b) represents a later time point than the figure shown in (a).

[0035] When the control system C cannot execute the first selection process as the selection process (specifically, when the upper lifting device 6U and the lower lifting device 6L cannot receive the maximum number of articles W that can be held in the first selection process), the control system C executes the second selection process as the selection process. Thus, the control system C preferentially executes the first selection process. And in the first selection process, when the upper lifting device 6U and the lower lifting device 6L cannot receive the maximum number of articles W that can be held, the control system C preferentially receives the maximum number of articles W that can be held by the upper lifting device 6U and the lower lifting device 6L and executes another selection process (here, the second selection process).

[0036] The second selection process is a selection process that makes the lowest-level hierarchical conveyor 4 (Z1) among the hierarchical conveyors 4 where the article W received by the upper lifting device 6U is placed the same as the highest-level hierarchical conveyor 4 (Z2) among the hierarchical conveyors 4 where the article W received by the lower lifting device 6L is placed. In the second selection process, basically, the articles W received by each of the upper lifting device 6U and the lower lifting device 6L are selected so that the upper lifting device 6U and the lower lifting device 6L can receive the maximum number of articles W that they can hold. FIGS. 6, 7, and 14 show how the articles W selected by the second selection process are received by each of the upper lifting device 6U and the lower lifting device 6L. In these figures, article W[1] and article W[2] are selected as the articles W received by the upper lifting device 6U, and article W[3] and article W[4] are selected as the articles W received by the lower lifting device 6L.

[0037] As shown in FIG. 5, the control system C is configured to execute a delivery process of delivering a plurality of articles W from the upper lifting device 6U and the lower lifting device 6L to the unloading device 2 in a predetermined delivery order. The delivery order is determined based on, for example, an order (such as a shipping order generated based on an order from the shipping destination of the article W). The order is generated by the control system C or another control device (for example, a management device superior to the control system C) that can communicate with the control system C.

[0038] In the transfer process, the upper lifting device 6U or the lower lifting device 6L moves in the Z direction to the height corresponding to the unloading device 2 in the order of the lifting device holding the article W[1], the lifting device holding the article W[2], the lifting device holding the article W[3], and the lifting device holding the article W[4], and transfers the article W to the unloading device 2. When two articles W with consecutive transfer orders are held by the same lifting device, the two articles W are transferred to the unloading device 2 in the order corresponding to the transfer order while the lifting device is arranged at the height corresponding to the unloading device 2. In the example shown in FIG. 5, after the upper lifting device 6U holding the article W[1] and the article W[2] moves in the Z direction to the height corresponding to the unloading device 2 and transfers the article W[1] and the article W[2] to the unloading device 2 (see FIG. 5(a)), the lower lifting device 6L holding the article W[3] and the article W[4] moves in the Z direction to the height corresponding to the unloading device 2 and transfers the article W[3] and the article W[4] to the unloading device 2 (see FIG. 5(b)). Note that when all of the articles W[1], W[2], W[3], and W[4] are transferred to the unloading device 2, the transfer order of the other articles W is advanced by four. Therefore, the articles W[5], W[6], W[7], and W[8] become the new articles W[1], W[2], W[3], and W[4].

[0039] Hereinafter, the four articles W of the articles W[1], W[2], W[3], and W[4] are simply referred to as four articles W. FIG. 3 shows the holding patterns of the four articles W in the upper lifting device 6U and the lower lifting device 6L. Each of the upper lifting device 6U and the lower lifting device 6L transfers the articles W to the unloading device 2 in order from the article W held on the first side X1 in the X direction (the side where the unloading device 2 is arranged). Therefore, by holding the four articles W in any of the six holding patterns (pattern 1 to pattern 6) shown in FIG. 3 in the upper lifting device 6U and the lower lifting device 6L, the four articles W can be transferred from the upper lifting device 6U and the lower lifting device 6L to the unloading device 2 in a predetermined transfer order.

[0040] Figures 4, 6, and 7 show the situation where four articles W are held by the upper lifting device 6U and the lower lifting device 6L in the pattern 1 shown in FIG. 3. FIG. 4 shows the first selection process as the selection process and how each of the upper lifting device 6U and the lower lifting device 6L receives the article W selected by the first selection process. FIGS. 6 and 7 show the second selection process as the selection process and how each of the upper lifting device 6U and the lower lifting device 6L receives the article W selected by the second selection process. Each of the upper lifting device 6U and the lower lifting device 6L receives a plurality of articles W such that the article W with the earlier handover order is arranged on the first side X1 in the X direction (the side where the unloading device 2 is arranged). Specifically, each of the upper lifting device 6U and the lower lifting device 6L receives a plurality of articles W in order from the article W with the earlier handover order.

[0041] The handover of the article W from the hierarchical conveyor 4 to the lifting conveyor 6 is performed in order from the article W arranged on the first side X1 in the X direction (the side where the lifting conveyor 6 is arranged). Therefore, when a plurality of articles W (two articles W in FIG. 6 and three articles W in FIG. 7) out of the four articles W shown in FIGS. 6 and 7 are arranged on the hierarchical conveyor 4 of the same level, the transport vehicle 5 transports the plurality of articles W from the shelf unit 10 to the hierarchical conveyor 4 such that the article W with the earlier handover order is arranged on the first side X1 in the X direction in the hierarchical conveyor 4.

[0042] As in patterns 1 and 2 shown in FIG. 3, in each of the upper lifting device 6U and the lower lifting device 6L, the condition that the articles W are held in a continuous order according to the delivery order is defined as the "first condition". Also, as in patterns 3 and 4 shown in FIG. 3, in either the upper lifting device 6U or the lower lifting device 6L (the lower lifting device 6L in pattern 3 and the upper lifting device 6U in pattern 4), the condition that the articles W are held in a continuous order according to the delivery order is defined as the "second condition". Although the technology of the present disclosure is not limited to such a configuration, in the present embodiment, the control system C executes the selection process as follows in both the first selection process and the second selection process. The control system C executes the selection process so as to satisfy the first condition. When the control system C cannot execute the selection process so as to satisfy the first condition, it executes the selection process so as to satisfy the second condition. When the control system C can neither execute the selection process so as to satisfy the first condition nor execute the selection process so as to satisfy the second condition, it executes the selection process so that neither the first condition nor the second condition is satisfied. Since the control system C executes the selection process in this way, patterns 1 and 2 are preferentially selected over patterns 3 to 6, and patterns 3 and 4 are preferentially selected over patterns 5 and 6.

[0043] Although the technology of the present disclosure is not limited to such a configuration, in the present embodiment, in both the first selection process and the second selection process, the control system C executes the selection process as follows. In the selection process, the control system C causes the one arranged on the first side in the vertical direction among the upper lifting device 6U and the lower lifting device 6L, such as in patterns 1, 3, and 5, to hold the article W whose delivery order is on the rear side. In the present embodiment, the first side in the vertical direction is the lower side Z1, and the one arranged on the first side in the vertical direction among the upper lifting device 6U and the lower lifting device 6L is the lower lifting device 6L. When the control system C cannot cause the one arranged on the first side in the vertical direction among the upper lifting device 6U and the lower lifting device 6L to hold the article W whose delivery order is on the rear side in the selection process, in the selection process, the control system C causes the one arranged on the second side in the vertical direction, which is the opposite side of the first side in the vertical direction, among the upper lifting device 6U and the lower lifting device 6L, such as in patterns 2, 4, and 6, to hold the article W whose delivery order is on the rear side. In the present embodiment, the second side in the vertical direction is the upper side Z2, and the one arranged on the second side in the vertical direction among the upper lifting device 6U and the lower lifting device 6L is the upper lifting device 6U. Since the control system C executes the selection process in this way, patterns 1, 3, and 5 are preferentially selected over patterns 2, 4, and 6.

[0044] In this way, patterns 1 and 2 are preferentially selected over patterns 3 to 6, and patterns 3 and 4 are preferentially selected over patterns 5 and 6. Also, patterns 1, 3, and 5 are preferentially selected over patterns 2, 4, and 6. Therefore, the six holding patterns shown in FIG. 3 are, in order from the one preferentially selected, pattern 1, pattern 2, pattern 3, pattern 4, pattern 5, and pattern 6.

[0045] Since the control system C executes the selection process as described above, which of the four articles W are held by the upper lifting device 6U and the lower lifting device 6L in any of the six holding patterns shown in FIG. 3 is determined according to the arrangement pattern of the four articles W in the hierarchical conveyor 4, or is determined according to the priority relationship between the arrangement pattern and the six holding patterns. The selection rules of the holding patterns (FIG. 3) according to the arrangement patterns of the four articles W shown in FIGS. 8 to 13 are set in consideration of the above-described respective priority relationships. Therefore, by selecting the holding pattern according to the arrangement pattern of the four articles W according to the selection rules shown in FIGS. 8 to 13, the selection process considering the above-described respective priority relationships is being performed. Note that the selection rules of the holding patterns shown in FIGS. 8 to 13 are an example, and can be appropriately changed according to the content of the priority relationships considered in the selection process, whether or not the priority relationships are considered in the selection process, and the like.

[0046] Each of FIGS. 8 to 13 shows the arrangement pattern of the four articles W in the hierarchical conveyor 4. In these figures, only the hierarchical conveyors 4 in which at least any one of the four articles W is arranged are shown side by side in the Z direction. The two hierarchical conveyors 4 adjacent to each other in the Z direction in each figure do not have to be the two hierarchical conveyors 4 arranged in adjacent layers in the Z direction, and other hierarchical conveyors 4 may be arranged between these two hierarchical conveyors 4 in the Z direction. And in FIGS. 8 to 13, the arrangement patterns in which the four articles W are divided and arranged on the four hierarchical conveyors 4 are classified into "four stages", the arrangement patterns in which the four articles W are divided and arranged on the three hierarchical conveyors 4 are classified into "three stages", and the arrangement patterns in which the four articles W are divided and arranged on the two hierarchical conveyors 4 are classified into "two stages". Note that how the four articles W are arranged on the hierarchical conveyor 4 in any arrangement pattern is determined according to which layer (stage) of the shelf portion 10 the four articles W are stored in.

[0047] When four articles W are arranged on the hierarchical conveyor 4 in any of the arrangement patterns shown in Fig. 8, a selection process is executed so that the four articles W are held by the upper lifting device 6U and the lower lifting device 6L in Pattern 1. That is, Articles W[1] and W[2] are selected as the articles W received by the upper lifting device 6U, and Articles W[3] and W[4] are selected as the articles W received by the lower lifting device 6L. The arrangement patterns of the four articles W shown in Figs. 4(a), 6(a), and 7(a) are included in the arrangement patterns shown in Fig. 8.

[0048] Thus, when four articles W are arranged on the hierarchical conveyor 4 in any of the arrangement patterns shown in Fig. 8, Articles W[1] and W[2] are selected as the articles W received by the upper lifting device 6U so that the articles W are held in Pattern 1, and Articles W[3] and W[4] are selected as the articles W received by the lower lifting device 6L. When four articles W are arranged on the hierarchical conveyor 4 in any of the arrangement patterns shown in Fig. 9, Articles W[3] and W[4] are selected as the articles W received by the upper lifting device 6U so that the articles W are held in Pattern 2, and Articles W[1] and W[2] are selected as the articles W received by the lower lifting device 6L.

[0049] When four articles W are arranged on the hierarchical conveyor 4 in any of the arrangement patterns shown in Fig. 10, Articles W[1] and W[4] are selected as the articles W received by the upper lifting device 6U so that the articles W are held in Pattern 3, and Articles W[2] and W[3] are selected as the articles W received by the lower lifting device 6L. When four articles W are arranged on the hierarchical conveyor 4 in any of the arrangement patterns shown in Fig. 11, Articles W[2] and W[3] are selected as the articles W received by the upper lifting device 6U so that the articles W are held in Pattern 4, and Articles W[1] and W[4] are selected as the articles W received by the lower lifting device 6L.

[0050] When four articles W are arranged in the hierarchical conveyor 4 in any of the arrangement patterns shown in FIG. 12, articles W[1] and W[3] are selected as the articles W received by the upper lifting device 6U, and articles W[2] and W[4] are selected as the articles W received by the lower lifting device 6L so that the articles W are held in pattern 5. When four articles W are arranged in the hierarchical conveyor 4 in any of the arrangement patterns shown in FIG. 13, articles W[2] and W[4] are selected as the articles W received by the upper lifting device 6U, and articles W[1] and W[3] are selected as the articles W received by the lower lifting device 6L so that the articles W are held in pattern 6.

[0051] When all of the four articles W are stored in the shelf portion 10 on the same level, as shown in FIG. 14, all of the four articles W are transferred from the same hierarchical conveyor 4 to the lifting conveyor 6. In FIG. 14, with articles W[1], W[2], and W[3] arranged in the same hierarchical conveyor 4, as articles W[1] and W[2] are transferred to the upper lifting device 6U, article W[4] is arranged in the hierarchical conveyor 4. Then, articles W[3] and W[4] are transferred to the lower lifting device 6L. Thus, when all of the four articles W are stored in the shelf portion 10 on the same level, articles W[1] and W[2] are selected as the articles W received by the upper lifting device 6U, and articles W[3] and W[4] are selected as the articles W received by the lower lifting device 6L so that the articles W are held in pattern 1.

[0052] Incidentally, there may be a hierarchical conveyor 4 (hereinafter referred to as "upper-side limited hierarchical conveyor") in which only the upper lifting device 6U can receive the article W, or a hierarchical conveyor 4 (hereinafter referred to as "lower-side limited hierarchical conveyor") in which only the lower lifting device 6L can receive the article W. For example, as shown in FIGS. 15 to 17, due to the presence of a ceiling or the like, the upper lifting device 6U cannot retract to the upper side Z2, so two hierarchical conveyors 4 (i.e., the hierarchical conveyors 4 of the uppermost layer and the layer immediately below it) from the upper side Z2 may become upper-side limited hierarchical conveyors. In this case, if three or more of the four articles W are arranged on the upper-side limited hierarchical conveyor, neither the first selection process nor the second selection process can receive the maximum number of articles W (here, four articles W) that the upper lifting device 6U and the lower lifting device 6L can hold.

[0053] Also, although not shown, due to the presence of a floor or the like, the lower lifting device 6L cannot retract to the lower side Z1, so two hierarchical conveyors 4 (i.e., the hierarchical conveyors 4 of the lowermost layer and the layer immediately above it) from the lower side Z1 may become lower-side limited hierarchical conveyors. In this case, if three or more of the four articles W are arranged on the lower-side limited hierarchical conveyor, neither the first selection process nor the second selection process can receive the maximum number of articles W that the upper lifting device 6U and the lower lifting device 6L can hold.

[0054] In addition, even when one of the upper lifting device 6U and the lower lifting device 6L can receive only some of the four articles W due to the size, shape, etc. of the article W, a situation may occur in which the maximum number of articles W that the upper lifting device 6U and the lower lifting device 6L can hold cannot be received.

[0055] When the control system C cannot receive the maximum number of articles W that the upper lifting device 6U and the lower lifting device 6L can hold in both the first selection process and the second selection process, the first selection process or the second selection process is executed so as to receive less than the maximum number of articles W that the upper lifting device 6U and the lower lifting device 6L can hold, and the remaining articles W are targeted for the next first selection process or second selection process. The articles W less than the above maximum number (here, three or less articles W) are one or more consecutive articles W in the delivery order starting from the article W with the earliest delivery order (i.e., article W[1]).

[0056] In the situation shown in FIG. 15, although four articles W are arranged on the hierarchical conveyor 4 in an arrangement pattern (see FIG. 8) that can hold the article W in pattern 1, the lower lifting device 6L cannot receive the article W[3] and the article W[4]. That is, the upper lifting device 6U and the lower lifting device 6L cannot receive the maximum number of articles W (here, four articles W) that they can hold. Therefore, the first selection process or the second selection process (here, the first selection process) is executed so as to receive less than the maximum number of articles W that the upper lifting device 6U and the lower lifting device 6L can hold, and the remaining articles W are targeted for the next first selection process or second selection process. In FIG. 15, the articles W[1] and the article W[2] are selected as the articles W to be received by the upper lifting device 6U, and the articles W[3] and the article W[4] are targeted for the next first selection process or second selection process. Specifically, for the article W[N] related to the next cycle as the article W[N′], the article W[3] becomes the article W[1′], the article W[4] becomes the article W[2′], the article W[5] becomes the article W[3′], and the article W[6] becomes the article W[4′].

[0057] In addition, when the lower lifting device 6L does not receive the article W as shown in the situation of FIG. 15, the hierarchical conveyor 4 on which the article W received by the lower lifting device 6L is arranged is regarded as being arranged below the lowermost hierarchical conveyor 4 in the Z1 direction, and although not shown in the figure, when the upper lifting device 6U does not receive the article W, the hierarchical conveyor 4 on which the article W received by the upper lifting device 6U is arranged is regarded as being arranged above the uppermost hierarchical conveyor 4 in the Z2 direction. Therefore, in these cases, the lowermost hierarchical conveyor 4 in the Z1 direction among the hierarchical conveyors 4 on which the article W received by the upper lifting device 6U is arranged is above the Z2 direction of the uppermost hierarchical conveyor 4 among the hierarchical conveyors 4 on which the article W received by the lower lifting device 6L is arranged, and the first selection process is executed.

[0058] In the situation shown in FIG. 16, the lower lifting device 6L cannot receive the article W[4]. In FIG. 16, by executing the first selection process, the articles W[1] and W[2] are selected as the articles W received by the upper lifting device 6U, and the article W[3] is selected as the article W received by the lower lifting device 6L. And the article W[4] is the target of the next first selection process or second selection process. Specifically, the article W[4] becomes the article W[1'], the article W[5] becomes the article W[2'], the article W[6] becomes the article W[3'], and the article W[7] becomes the article W[4'].

[0059] In the situation shown in FIG. 17, the lower lifting device 6L cannot receive the articles W[3] and W[4]. In FIG. 17, by executing the first selection process, the articles W[1] and W[3] are selected as the articles W received by the upper lifting device 6U, and the article W[2] is selected as the article W received by the lower lifting device 6L. And the article W[4] is the target of the next first selection process or second selection process. Specifically, the article W[4] becomes the article W[1'], the article W[5] becomes the article W[2'], the article W[6] becomes the article W[3'], and the article W[7] becomes the article W[4'].

[0060] In FIG. 17, it is assumed that the control system C executes the first selection process or the second selection process so that the upper lifting device 6U and the lower lifting device 6L can receive as many articles W as possible, which is less than the maximum number they can hold. Therefore, article W[1] and article W[3] are selected as the articles W received by the upper lifting device 6U, and article W[2] is selected as the article W received by the lower lifting device 6L. Different from such a configuration, for example, in at least one of the upper lifting device 6U and the lower lifting device 6L, holding the articles W in a continuous order according to the delivery order may be prioritized over receiving a large number of articles W. In this case, article W[1] and article W[2] are selected as the articles W received by the upper lifting device 6U, article W[3] becomes article W[1'], article W[4] becomes article W[2'], article W[5] becomes article W[3'], and article W[6] becomes article W[4'].

[0061] 〔Other Embodiments〕 (1) In the above embodiment, the configuration in which the control system C executes the second selection process as the selection process when it cannot execute the first selection process as the selection process has been described as an example. However, the present disclosure is not limited to such a configuration, and when the control system C cannot execute the first selection process as the selection process, the first selection process may be executed so as to receive articles W less than the maximum number that the upper lifting device 6U and the lower lifting device 6L can hold, and the remaining articles W may be targeted for the next first selection process.

[0062] (2) In the above-described embodiment, the configuration in which the position in the Z direction where the carry-out device 2 receives the article W from each of the upper lifting device 6U and the lower lifting device 6L is biased toward the lower side Z1 in the entire Z direction of the lifting path 60 has been described as an example. However, the present disclosure is not limited to such a configuration, and the position in the Z direction where the carry-out device 2 receives the article W from each of the upper lifting device 6U and the lower lifting device 6L may be biased toward the upper side Z2 in the entire Z direction of the lifting path 60. In this case, the upper side Z2 corresponds to the "first side in the vertical direction". In this case, unlike the above-described embodiment, the six holding patterns shown in FIG. 3 are, in order from the one preferentially selected, pattern 2, pattern 1, pattern 4, pattern 3, pattern 6, and pattern 5. Further, the position in the Z direction where the carry-out device 2 receives the article W from each of the upper lifting device 6U and the lower lifting device 6L may be configured not to be biased toward either the lower side Z1 or the upper side Z2 in the entire Z direction of the lifting path 60.

[0063] (3) In the above-described embodiment, the configuration in which the control system C executes a handover process of handing over a plurality of articles W from the upper lifting device 6U and the lower lifting device 6L to the carry-out device 2 in a predetermined handover order has been described as an example. However, the present disclosure is not limited to such a configuration, and the control system C may be configured to hand over a plurality of articles W from the upper lifting device 6U and the lower lifting device 6L to the carry-out device 2 in an arbitrary order.

[0064] (4) In the above-described embodiment, the configuration in which the upper lifting device 6U and the lower lifting device 6L can each hold two articles W has been described as an example. However, the present disclosure is not limited to such a configuration, and the upper lifting device 6U and the lower lifting device 6L may each be configured to hold three or more articles W. Further, in a case where the configurations of the holding portions of the article W (for example, the dimensions of the holding portions) are different between the upper lifting device 6U and the lower lifting device 6L, the maximum number of articles W that the upper lifting device 6U can hold (a value of 2 or more) and the maximum number of articles W that the lower lifting device 6L can hold (a value of 2 or more) may be different.

[0065] (5) In the above embodiment, the hierarchical conveyor device 4 is described by taking the configuration of a conveyor as an example. However, the present disclosure is not limited to such a configuration. For example, a plurality of transport carts 5 arranged in multiple layers so as to be aligned in the Z direction may constitute the hierarchical conveyor device 4. In this case, the lifting and conveying device 6 is configured to receive the article W from the transport cart 5 serving as the hierarchical conveyor device 4.

[0066] (6) In the above embodiment, the configuration in which the unloading device 2 and the loading device 3 are conveyors is described by taking it as an example. However, the present disclosure is not limited to such a configuration, and at least one of the unloading device 2 and the loading device 3 may be a transport cart such as a rail-mounted cart or a trackless cart, a pusher for pushing out the article W, a robot arm, or the like.

[0067] (7) In the above embodiment, the configuration in which the article conveying facility 100 includes the storage shelf 1, the loading device 3, and the transport cart 5 is described by taking it as an example. However, the present disclosure is not limited to such a configuration, and the article conveying facility 100 may be configured not to include at least any of these. For example, when the unloading device 2 is used as either an unloading or loading device according to the state of the article conveying facility 100 at that time, the article conveying facility 100 may be configured not to include a loading device 3 different from the unloading device 2. In this case, the lifting and conveying device 6 is used for outbound when the unloading device 2 is used for unloading, and is used for inbound when the unloading device 2 is used for loading.

[0068] (8) In addition, the configurations disclosed in the above-described embodiments can be applied in combination with the configurations disclosed in other embodiments (including combinations of the embodiments described as other embodiments) as long as there is no contradiction. Regarding other configurations as well, all the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be appropriately made within the scope not departing from the gist of the present disclosure.

[0069] Summary of this Embodiment Hereinafter, an overview of the article conveying facility described above will be described.

[0070] The article conveying equipment is an article conveying equipment including a multi-layer conveying device arranged in a plurality of layers so as to be arranged vertically, a lifting and lowering conveying device for conveying the article received from the multi-layer conveying device in the vertical direction, an unloading device for unloading the article received from the lifting and lowering conveying device, and a control system for controlling the multi-layer conveying device and the lifting and lowering conveying device. The lifting and lowering conveying device includes an upper lifting and lowering device that moves in the vertical direction along a lifting and lowering path, and a lower lifting and lowering device that moves in the vertical direction along the lifting and lowering path below the upper lifting and lowering device. The upper lifting and lowering device and the lower lifting and lowering device are each configured to be able to hold a plurality of the articles. The control system executes, as a selection process for selecting the articles received by each of the upper lifting and lowering device and the lower lifting and lowering device, a first selection process such that the lowermost one of the multi-layer conveying devices in which the articles received by the upper lifting and lowering device are arranged is above the uppermost one of the multi-layer conveying devices in which the articles received by the lower lifting and lowering device are arranged.

[0071] According to this configuration, when conveying a plurality of articles from the multi-layer conveying device to the unloading device by the lifting and lowering conveying device, by executing the first selection process, the vertical range in which the upper lifting and lowering device receives articles from the multi-layer conveying device and the vertical range in which the lower lifting and lowering device receives articles from the multi-layer conveying device can be made not to overlap. Thereby, it is easy to overlap the execution period of the receiving operation in which the upper lifting and lowering device receives articles from the multi-layer conveying device and the execution period of the receiving operation in which the lower lifting and lowering device receives articles from the multi-layer conveying device. Therefore, it is easy to improve the conveying efficiency of the articles by the lifting and lowering conveying device.

[0072] Here, when the first selection process cannot be executed as the selection process, it is preferable that the control system executes, as the selection process, a second selection process such that the lowermost one of the multi-layer conveying devices in which the articles received by the upper lifting and lowering device are arranged is the same as the uppermost one of the multi-layer conveying devices in which the articles received by the lower lifting and lowering device are arranged.

[0073] According to this configuration, when a plurality of articles are conveyed from the hierarchical conveyor to the unloading device by the lifting and conveying device, even when the first selection process cannot be executed, by executing the second selection process, the vertical range in which the upper lifting device receives articles from the hierarchical conveyor and the vertical range in which the lower lifting device receives articles from the hierarchical conveyor can be minimized. As a result, the execution period of the receiving operation in which the upper lifting device receives articles from the hierarchical conveyor and the execution period of the receiving operation in which the lower lifting device receives articles from the hierarchical conveyor are relatively easy to overlap. Therefore, it is easy to increase the conveyance efficiency of the articles by the lifting and conveying device.

[0074] As described above, in the configuration in which the control system executes the second selection process as the selection process when the first selection process cannot be executed as the selection process, the control system performs both the first selection process and the second selection process. When the upper lifting device and the lower lifting device cannot receive the maximum number of the articles that can be held, the first selection process or the second selection process is executed so that the upper lifting device and the lower lifting device receive less than the maximum number of the articles that can be held, and the remaining articles are made the target of the next first selection process or second selection process, which is preferable.

[0075] According to this configuration, by executing the first selection process and the second selection process so as to receive as many articles as possible that can be held by the upper lifting device and the lower lifting device, while increasing the conveyance efficiency of the articles by the lifting and conveying device, when the upper lifting device and the lower lifting device cannot receive the maximum number of articles that can be held, by making the remaining articles the target of the next first selection process or second selection process, the necessary articles can be surely conveyed to the unloading device.

[0076] In each of the above configurations, the unloading device is configured to receive the articles from the upper lifting device and the lower lifting device respectively at predetermined vertical positions, and the control system is configured to execute a handover process of handing over a plurality of the articles from the upper lifting device and the lower lifting device to the unloading device in a predetermined handover order. It is preferable that the control system executes the selection process so that the articles are held in consecutive orders according to the handover order in each of the upper lifting device and the lower lifting device.

[0077] According to this configuration, in the handover process, after all the articles held by one of the upper lifting device and the lower lifting device are handed over to the unloading device, all the articles held by the other of the upper lifting device and the lower lifting device are handed over to the unloading device, so that the articles can be handed over to the unloading device in a predetermined handover order. Therefore, even when the unloading device is configured to receive the articles at predetermined vertical positions, the number of lifting operations of the upper lifting device and the lower lifting device in the handover process can be reduced. Thus, it is easy to improve the conveyance efficiency of the articles by the lifting and conveying device.

[0078] As described above, in the configuration in which the control system executes the selection process so that the articles are held in consecutive orders according to the handover order in each of the upper lifting device and the lower lifting device, the vertical position at which the unloading device receives the articles from each of the upper lifting device and the lower lifting device is biased to the first vertical side, which is one side in the vertical direction, within the entire vertical direction of the lifting path. It is preferable that in the selection process, the one arranged on the first vertical side among the upper lifting device and the lower lifting device holds the articles whose handover order is on the rear side.

[0079] According to this configuration, the lifting device with the narrower vertical lifting range from the unloading device delivers the article to the unloading device after the lifting device with the wider lifting range. Therefore, the lifting device with the wider lifting range can finish delivering the article first and move towards receiving the next article. That is, the lifting device with a high possibility of having a long vertical movement distance for receiving the next article can start moving first. Thus, it is easy to improve the conveyance efficiency of the article by the lifting and conveying device.

[0080] The article conveying facility according to the present disclosure only needs to be able to achieve at least one of the above-described various effects.

Explanation of Reference Numerals

[0081] 2: Unloading device 4: Hierarchical conveying device 6: Lifting and conveying device 6U: Upper lifting device 6L: Lower lifting device 60: Lifting path 100: Article conveying facility C: Control system W: Article Z: Z direction (vertical direction) Z1: Lower side (first side in the vertical direction) Z2: Upper side

Claims

1. A hierarchical conveying device arranged in a vertical direction in a plurality of hierarchical levels; a lifting conveying device that conveys the article received from the level conveying device in a vertical direction; a carrying-out device that carries out the article received from the lifting and conveying device; and a control system for controlling the level conveying device and the lifting conveying device, the lifting and transporting device includes an upper lifting device that moves vertically along a lifting path, and a lower lifting device that moves vertically along the lifting path below the upper lifting device, The upper lifting device and the lower lifting device are each configured to hold a plurality of the articles, The control system performs a first selection process as a selection process for selecting the items to be received by each of the upper lifting device and the lower lifting device, such that the lowest hierarchical conveying device among the hierarchical conveying devices on which the items to be received by the upper lifting device are arranged is above the highest hierarchical conveying device among the hierarchical conveying devices on which the items to be received by the lower lifting device are arranged.

2. The item transport equipment of claim 1, wherein when the control system cannot execute the first selection process as the selection process, it executes a second selection process as the selection process, in which the lowest level conveying device among the level conveying devices on which the item to be received by the upper lifting device is arranged is the same as the highest level conveying device among the level conveying devices on which the item to be received by the lower lifting device is arranged.

3. The item transport equipment of claim 2, wherein if the control system is unable to receive the maximum number of items that the upper lifting device and the lower lifting device can hold in both the first selection process and the second selection process, it executes the first selection process or the second selection process to receive less than the maximum number of items that the upper lifting device and the lower lifting device can hold, and makes the remaining items the subject of the next first selection process or the second selection process.

4. the discharge device is configured to receive the article from each of the upper lifting device and the lower lifting device at a predetermined vertical position; the control system is configured to execute a delivery process for delivering the plurality of articles from the upper lifting device and the lower lifting device to the carry-out device in a predetermined delivery order; The item transport facility according to claim 1 , wherein the control system executes the selection process so that the items are held in each of the upper lifting device and the lower lifting device in a consecutive order according to the delivery order.

5. a vertical position where the discharge device receives the article from each of the upper lifting device and the lower lifting device is biased toward a first vertical side, which is one side of the vertical direction, within the entire vertical area of ​​the lifting path; The item transport equipment according to claim 4, wherein, in the selection process, the control system causes one of the upper lifting device and the lower lifting device arranged on the first side in the vertical direction to hold the item that is later in the delivery order.

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