Transport System

Abstract

To provide a carrier system capable of reducing the power consumption of a carrier device while continuing to carry a load by the carrier device.SOLUTION: A carrier system 2 comprises a carrier device 16 for carrying a load 6 and a controller 8 which controls the operation of the carrier device 16. The controller 8 acquires a cumulative power consumption which is a cumulative value of electric power that the carrier device 16 consumes in a first period ending at the present time and a predicted power consumption which is a predicted value of electric power that the carrier device 16 consumes in a second period starting at the present time, and controls the operation of the carrier device 16 to lower the carrying capability of the carrier device 16 when the sum of the cumulative power consumption and the predicted power consumption exceeds a threshold.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a conveyance system that conveys luggage using a conveyance device. [Background technology]

[0002] For example, an automated warehouse system is known in which a transport device such as a stacker crane moves cargo into and out of a rack. In the automated warehouse system disclosed in Patent Document 1, at night, the stacker crane moves a weight located on the bottom shelf of the rack to the top shelf of the rack. Furthermore, during peak hours in the daytime when the power consumption of the stacker crane is at its peak, the stacker crane generates regenerative power by lowering the weight located on the top shelf of the rack. This generated regenerative power is supplied to stacker cranes other than the stacker crane in question, thereby reducing the power consumption of the other stacker cranes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-088696 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional automated warehouse system described above, during peak hours, while the stacker crane is lowering its weight to generate regenerative power, the stacker crane is unable to transport cargo, resulting in a problem of reduced throughput (efficiency of cargo transportation and processing).

[0005] The present invention seeks to solve the above-mentioned problems, and its purpose is to provide a conveying system that can reduce the amount of power consumed by a conveying device while continuing to transport luggage using the conveying device. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, a conveying system according to one embodiment of the present invention comprises a conveying device for conveying cargo and a controller for controlling the operation of the conveying device, wherein the controller acquires cumulative power consumption, which is the cumulative value of the amount of power consumed by the conveying device within a first period ending at the present time, and predicted power consumption, which is the predicted value of the amount of power consumed by the conveying device within a second period starting at the present time, and controls the operation of the conveying device so as to reduce the conveying capacity of the conveying device when the sum of the cumulative power consumption and the predicted power consumption exceeds a threshold value.

[0007] According to this aspect, the controller controls the operation of the transport device so as to reduce the transport capacity of the transport device when the sum of the accumulated power consumption and the predicted power consumption exceeds a threshold value, thereby reducing the power consumption of the transport device while continuing to transport packages by the transport device.

[0008] For example, in a conveying system according to one aspect of the present invention, the controller may be configured to control the operation of the conveying device so as to reduce the conveying speed or conveying acceleration of the luggage by the conveying device when the sum of the cumulative power consumption and the predicted power consumption exceeds the threshold value.

[0009] According to this aspect, when the sum of the cumulative power consumption and the predicted power consumption exceeds a threshold, the transport speed or transport acceleration of the transport device is reduced while the transport device continues to transport the luggage. This makes it possible to reduce the power consumption of the transport device while maintaining a certain level of throughput (package transport processing efficiency).

[0010] For example, in a conveying system according to one aspect of the present invention, the controller may be configured to control the operation of the conveying device so as to temporarily suspend the conveying of the cargo by the conveying device when the sum of the cumulative power consumption and the predicted power consumption exceeds the threshold value.

[0011] According to this aspect, when the sum of the cumulative power consumption and the predicted power consumption exceeds a threshold, the transport of luggage by the transport device is temporarily suspended but continues, thereby reducing the power consumption of the transport device while maintaining a certain level of throughput (the efficiency of transporting luggage).

[0012] For example, in a conveying system according to one aspect of the present invention, the controller may be configured to control the operation of the conveying device so as to change the conveying process of the conveying device and reduce the conveying capacity of the conveying device when the sum of the accumulated power consumption and the predicted power consumption exceeds the threshold value.

[0013] According to this aspect, it is possible to more effectively reduce the amount of power consumed by the conveying device while continuing to transport packages using the conveying device.

[0014] For example, in a conveying system according to one aspect of the present invention, the controller may be configured to change the conveying process of the conveying device to a conveying process with a higher priority when the sum of the accumulated power consumption and the predicted power consumption exceeds the threshold value.

[0015] According to this aspect, the transport process having a higher priority can be executed preferentially. [Effects of the Invention]

[0016] According to a conveyance system according to one aspect of the present invention, it is possible to reduce the amount of power consumed by the conveyance device while continuing to transport packages using the conveyance device. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a top view showing an overview of a transport system according to an embodiment; [Figure 2] FIG. 2 is a block diagram showing a functional configuration of the transport system according to the embodiment. [Figure 3]FIG. 10 is a diagram illustrating an example of a table for recording the amount of power consumption of the transport device. [Figure 4] 10 is a graph showing an example of a change over time in the amount of power consumed by a transport device. [Figure 5] FIG. 2 is a diagram for explaining functions of a controller of the transport system according to the embodiment. [Figure 6] 10 is a flowchart showing a flow of processing by a controller of the transport system according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection forms, steps, step order, etc. shown in the following embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the following embodiments, components not recited in independent claims will be described as optional components.

[0019] (Embodiment) [1. Overview of the transport system] First, an overview of a transfer system 2 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a top view showing an overview of a transfer system 2 according to an embodiment.

[0020] As shown in Fig. 1, the conveyance system 2 is, for example, an automated warehouse system for storing and retrieving cargo 6 in an automated warehouse 4. The conveyance system 2 includes the automated warehouse 4 and a controller 8. The cargo 6 includes a pallet 10 and a plurality of items 12 placed on the pallet 10.

[0021] The automated warehouse 4 has racks 14a and 14b and a transport device 16. The transport device 16 operates by receiving power from, for example, a commercial power source.

[0022] The racks 14a, 14b are arranged facing each other in the horizontal direction (into the plane of FIG. 1) with a travel path 18 of a stacker crane 26 (described later) sandwiched between them. A plurality of shelves 20a, 20b for storing luggage 6 are arranged on the racks 14a, 14b, respectively. The plurality of shelves 20a, 20b are arranged in multiple tiers at intervals in the vertical direction (perpendicular to the plane of FIG. 1).

[0023] The transport device 16 is a device for transporting the luggage 6. The transport device 16 has an inlet conveyor 22, an outlet conveyor 24, and a stacker crane 26. The inlet conveyor 22 is a conveyor for storing the luggage 6 in the automated warehouse 4. The outlet conveyor 24 is a conveyor for retrieving the luggage 6 from the automated warehouse 4. The stacker crane 26 travels along the travel path 18 arranged between the rack 14a and the rack 14b. The stacker crane 26 receives the luggage 6 from the inlet conveyor 22 and transfers the received luggage 6 to a predetermined position on the rack 14a or the rack 14b. The stacker crane 26 also retrieves the luggage 6 stored on the rack 14a or the rack 14b and transfers the retrieved luggage 6 to the outlet conveyor 24.

[0024] The controller 8 controls the operation of the transport device 16. The function of the controller 8 will be described later.

[0025] [2. Functional configuration of the transport system] The functional configuration of the conveying system 2 according to the embodiment will be described with reference to Figs. 2 to 5. Fig. 2 is a block diagram showing the functional configuration of the conveying system 2 according to the embodiment. Fig. 3 is a diagram showing an example of a table 32 that records the amount of power consumption of the conveying device 16. Fig. 4 is a graph showing an example of the temporal change in the amount of power consumption of the conveying device 16. Fig. 5 is a diagram for explaining the function of the controller 8 of the conveying system 2 according to the embodiment.

[0026] 2, the conveyance system 2 includes, as functional components, the conveyance device 16 of the automated warehouse 4, a power meter 28, a memory 30, and a controller 8. The conveyance device 16 has already been described, so a description thereof will be omitted here.

[0027] The power meter 28 measures the amount of power consumed by the transport device 16. The power meter 28 outputs the measured amount of power consumed to the controller 8.

[0028] The memory 30 stores a table 32 shown in FIG. 3. The table 32 is a table for dividing the most recent 29 minutes into one-minute time intervals and recording the amount of power consumed by the transport device 2 in each time interval. In this case, there are 29 time intervals. One entry in the table 32 corresponds to one time interval. In the table 32, each entry has a number 34 and a power consumption amount 36. The number 34 is a serial number for each entry. The power consumption amount 36 is the amount of power consumed by the transport device 16 in the time interval corresponding to each entry. The power consumption amount 36 is the amount of power consumed expressed in units of, for example, "kWh."

[0029] The controller 8 acquires the amount of power consumption from the power meter 28 every minute and records the acquired amount of power consumption in the table 32 in the memory 30. As an example, consider the case where the amount of power consumption of the transport device 16 changes over time as shown in FIG. 4A. In the example shown in FIG. 4A, the amount of power consumption of the transport device 16 in the first minute from the start of measurement is P1 (kWh), the amount of power consumption of the transport device 16 in the second minute from the start of measurement is P2 (kWh), and the amount of power consumption of the transport device 16 in the third minute from the start of measurement is P3 (kWh). Furthermore, the amount of power consumption of the transport device 16 in the 29th minute from the start of measurement is P29 (kWh). In other words, the amount of power consumption of the transport device 16 in the nth minute (n = 1, 2, 3, . . . , 29) from the start of measurement is Pn (kWh). The start of measurement refers to the time when the power meter 28 starts measuring the amount of power consumption of the transport device 16.

[0030] In this case, as shown in (a) of Figure 3, when the first minute has elapsed since the start of measurement, the controller 8 records "P1 (kWh)" in the power consumption 36 of the entry numbered "1" in the table 32. Also, as shown in (a) of Figure 3, when the second minute has elapsed since the start of measurement, the controller 8 records "P2 (kWh)" in the power consumption 36 of the entry numbered "2" in the table 32.

[0031] 3A, when the third minute has elapsed since the start of measurement, the controller 8 records "P3 (kWh)" in the power consumption 36 of the entry numbered "3" in the table 32. Also, when the 29th minute has elapsed since the start of measurement, the controller 8 records "P29 (kWh)" in the power consumption 36 of the entry numbered "29" in the table 32. That is, when the nth minute (n=1, 2, 3, . . . , 29) has elapsed since the start of measurement, the controller 8 records "Pn (kWh)" in the power consumption 36 of the entry numbered "n" in the table 32.

[0032] As a result, as shown in (a) of Figure 4, when the current time is 29 minutes after the start of measurement, the power consumption amount 36 shown in (a) of Figure 3 is recorded in table 32 of memory 30.

[0033] In this way, the controller 8 increments the number 34 by "1" every minute, and records the power consumption amount obtained from the power meter 28 in the power consumption amount 36 of the entry with the number 34 corresponding to that minute. When one more minute has passed immediately after "P29 (kWh)" was recorded in the power consumption amount 36 of the entry with the number "29" in the table 32, the controller 8 overwrites and records the power consumption amount 36 of the entry with the number "1" with the power consumption amount obtained from the power meter 28 at that timing.

[0034] For example, consider the case where the power consumption of the transport device 16 during the 30th minute from the start of measurement is P30 (kWh), as shown in (b) of Figure 4. In this case, when the 30th minute has elapsed from the start of measurement, the controller 8 overwrites the power consumption 36 of the entry numbered "1" in the table 32 with "P30 (kWh)" and records it, as shown in (b) of Figure 3.

[0035] As a result, as shown in (b) of Figure 4, when the current time is 30 minutes after the start of measurement, the power consumption amount 36 shown in (b) of Figure 3 is recorded in table 32 of memory 30.

[0036] In this way, the power consumption amount for the past 29 minutes from the present time is updated every minute and recorded as a ring buffer in table 32. That is, table 32 always records the power consumption amount for each minute for the most recent 29 minutes.

[0037] Furthermore, the controller 8 can obtain the cumulative power consumption, which is the accumulated value of the amount of power consumed by the transport device 16 for the past 29 minutes (an example of a first period ending at the present time) by calculating the sum of the power consumption amounts 36 for numbers "1" to "29" in the table 32. For example, as shown in (a) of FIG. 4, when the present time is 29 minutes after the start of measurement, the controller 8 obtains the cumulative power consumption amount "P1+P2+P3+...+P29" by calculating the sum of the power consumption amounts 36 for numbers "1" to "29" in the table 32 shown in (a) of FIG.

[0038] The controller 8 also acquires predicted power consumption, which is a predicted value of the amount of power that the transport device 16 will consume in the next one minute from the present time (an example of a second period starting from the present time). The controller 8 acquires the predicted power consumption, for example, from the transport device 16 or a higher-level controller (not shown). For example, as shown in (a) of FIG. 5, when the present time is 29 minutes after the start of measurement, the controller 8 acquires "PA (kWh)" as the predicted power consumption in the next one minute from the present time.

[0039] Furthermore, as shown in (b) of FIG. 5, the controller 8 calculates the sum of the acquired cumulative power consumption and the predicted power consumption, "P1 + P2 + P3 + ··· + P29 + PA." Based on the result of comparing the calculated sum with a threshold, the controller 8 determines whether or not to reduce the conveying capacity of the conveying device 16. Here, the threshold is set based on an individual target demand value assigned to the conveying device 16 out of target demand values ​​(described later) set for the entire building in which the automated warehouse 4 is installed.

[0040] [3. Operation of the transport system] The operation of the transfer system 2 according to the embodiment will be described with reference to Fig. 3 to Fig. 6. Fig. 6 is a flowchart showing the flow of processing by the controller 8 of the transfer system 2 according to the embodiment.

[0041] As shown in Fig. 6, first, the controller 8 receives a transport instruction from, for example, a higher-level controller (S101). The transport instruction is, for example, a command to issue an instruction to retrieve the cargo 6a (see Fig. 1) stored on the top shelf 20b of the rack 14b. One cycle of transporting the cargo 6a related to the transport instruction, i.e., the process in which the stacker crane 26 retrieves the cargo 6a from the top shelf 20b of the rack 14b and transfers the retrieved cargo 6a to the outgoing conveyor 24, is completed within, for example, one minute.

[0042] Next, the controller 8 acquires the cumulative power consumption (S102). For example, as shown in (a) of FIG. 4, when the current time point is 29 minutes after the measurement start time point, the controller 8 calculates the sum of the power consumptions 36 in the numbers “1” to “29” of the table 32 shown in (a) of FIG. 3, thereby acquiring the cumulative power consumption “P1 + P2 + P3 + ··· + P29”.

[0043] Next, the controller 8 acquires the predicted power consumption (S103). Here, the predicted power consumption is a predicted value of the power consumption by the transfer device 16 for transferring the load 6a related to the transfer command in the next one minute from the current time point. For example, as shown in (a) of FIG. 5, when the current time point is 29 minutes after the measurement start time point, the controller 8 acquires “PA (kWh)” as the predicted power consumption in the next one minute from the current time point.

[0044] Next, the controller 8 calculates the sum “P1 + P2 + P3 + ··· + P29 + PA” of the acquired cumulative power consumption and the predicted power consumption, and determines whether the calculated sum exceeds the threshold value (S104).

[0045] When the calculated sum exceeds the threshold value (YES in S104), the controller 8 acquires the predicted power consumption when the transfer capacity of the transfer device 16 is reduced from the normal transfer capacity (S105). The controller 8 calculates the sum “P1 + P2 + P3 + ··· + P29 + PA” of the acquired cumulative power consumption and the predicted power consumption. When the calculated sum is below the threshold value (NO in S106), the controller 8 controls the operation of the transfer device 16 with a transfer capacity lower than the normal transfer capacity (S107). Specifically, the controller 8 controls the operation of the transfer device 16 so as to reduce the transfer speed of the load 6a by the transfer device 16 by a predetermined ratio (for example, several tens%) from the normal transfer speed. Thereby, the transfer device 16 transfers the load 6a at a transfer speed V2 (<V1) slower than the normal transfer speed V1. Note that “normal” means a state where the calculated sum is below the threshold value.

[0046] Return to step S106. If the calculated sum exceeds the threshold (YES in S106), the controller 8 acquires the predicted power consumption when the transport capacity of the transport device 16 is further reduced (S108). Then, return to step S106.

[0047] Note that the controller 8 may control the operation of the transport device 16 so that the transport acceleration of the load 6a by the transport device 16 is reduced by a predetermined ratio (for example, several tens of %) compared to the normal transport acceleration. Thereby, the transport device 16 transports the load 6a at a slower transport acceleration A2 (<A1) than the normal transport acceleration A1.

[0048] Alternatively, the controller 8 may control the operation of the transport device 16 so as to temporarily (for example, for several tens of seconds) interrupt the transport of the load 6a by the transport device 16. Thereby, the transport device 16 delays the start timing of the transport of the load 6a compared to the normal transport start timing (for example, immediately after the controller 8 receives the transport instruction).

[0049] Return to step S104. If the calculated sum is less than or equal to the threshold (NO in S104), the controller 8 controls the operation of the transport device 16 so as to maintain the transport capacity of the transport device 16 at the normal transport capacity (S109). Thereby, the transport device 16 transports the load 6a at the normal transport start timing and at the normal transport speed V1 and the normal transport acceleration A1.

[0050] [4. Effects] Generally, in order to suppress the peak of power consumption, in the electricity rate contract between the power company and the electricity customer, the basic usage fee of the electricity rate is determined based on the maximum demand value. The maximum demand value measures the average power consumption every 30 minutes (hereinafter referred to as the "30 - minute demand value") and refers to the maximum of each 30 - minute demand value over the most recent 12 months. Here, "30 minutes" means a 30 - minute period from 0 minutes to 30 minutes per hour or a 30 - minute period from 30 minutes to 60 minutes per hour. Note that the unit of the demand value is "kW / h".

[0051] In this embodiment, the controller 8 calculates the sum of the cumulative power consumption (power consumption over the past 29 minutes from the present time) and the predicted power consumption (power consumption over the next 1 minute from the present time), and if the calculated sum exceeds a threshold value, controls the operation of the conveying device 16 so as to reduce the conveying capacity of the conveying device 16 below its normal conveying capacity. Here, the threshold value is set based on an individual target demand value assigned to the conveying device 16 out of target demand values, which are target values ​​for 30-minute demand values ​​set for the entire building in which the automated warehouse 4 is installed.

[0052] This makes it possible to reduce the amount of power consumed by the conveying device 16 even when the conveying device 16 transports the luggage 6a according to the transport instruction received by the controller 8. This makes it possible to prevent the 30-minute demand value of the conveying device 16 from exceeding the individual target demand value. As a result, it is possible to prevent the 30-minute demand value of the entire building in which the automated warehouse 4 is installed from exceeding the target demand value, making it possible to keep the basic electricity usage fee low.

[0053] Furthermore, if the calculated sum exceeds the threshold value, the conveyance capacity of the conveyance device 16 is reduced below the normal conveyance capacity, but the conveyance device 16 continues to convey the luggage 6. This makes it possible to maintain a certain degree of efficiency in conveying the luggage 6. As a result, it is possible to reduce the amount of power consumed by the conveyance device 16 while continuing to convey the luggage 6 by the conveyance device 16.

[0054] (Variations, etc.) Although the transport system of the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments. The present invention also includes modifications that can be made to the above embodiments by those skilled in the art, and other modifications that can be realized by arbitrarily combining the components of the above embodiments.

[0055] In the above embodiment, the conveying device 16 is configured to include a stacker crane 26, but this is not limited to this, and instead of the stacker crane 26, it may be configured to include, for example, a tracked vehicle that runs along a track installed on the floor or ceiling.

[0056] Furthermore, in the above embodiment, the amount of power consumption is updated every minute, but this is not limitative and the amount of power consumption may be updated at any time interval.

[0057] Furthermore, if the conveying device 16 includes an unmanned guided vehicle (such as an AGV) that runs on power from a battery, the demand value during peak times can be reduced by providing a power storage device in the charging device of the unmanned guided vehicle and charging the battery of the unmanned guided vehicle with the power stored in the power storage device.

[0058] In the above embodiment, when the calculated sum exceeds a threshold value, the controller 8 controls the operation of the conveying device 16 to reduce the conveying capacity of the conveying device 16 below its normal conveying capacity. In this case, the controller 8 may change the conveying process of the conveying device 16 and control the operation of the conveying device 16 to reduce the conveying capacity of the conveying device 16 below its normal conveying capacity. "Changing the conveying process of the conveying device 16" means, for example, changing the type of luggage 6 to be conveyed. For example, when the controller 8 receives a conveying instruction to convey a first luggage and determines that the amount of power consumed by the conveying device 16 when conveying a second luggage is lower than the amount of power consumed by the conveying device 16 when conveying the first luggage, the controller 8 changes the luggage 6 to be conveyed from the first luggage to the second luggage and controls the operation of the conveying device 16 to reduce the conveying capacity of the conveying device 16 below its normal conveying capacity.

[0059] At this time, the controller 8 may change the transport process of the transport device 16 to a transport process with a higher priority. For example, when the controller 8 receives a transport instruction to transport a first package and determines that a second package has a higher priority than the first package, the controller 8 changes the package 6 to be transported from the first package to the second package and controls the operation of the transport device 16 so as to reduce the transport capacity of the transport device 16 below its normal transport capacity. This allows the transport process with a higher priority to be executed preferentially. [Industrial Applicability]

[0060] The conveyance system according to the present invention can be applied to, for example, an automated warehouse system for storing and retrieving cargo in an automated warehouse. [Explanation of symbols]

[0061] 2. Transport System 4. Automated warehouse 6. Luggage 8 Controller 10 palettes 12 Goods 14a, 14b rack 16. Conveying equipment 18 Traveling aisle 20a, 20b shelves 22 Incoming conveyor 24 Outgoing conveyor 26 Stacker Crane 28 Power meter 30 memory 32 tables 34 Number 36 Power consumption

Claims

1. a conveying device for conveying luggage; a controller for controlling the operation of the transport device, The controller Acquire a cumulative power consumption amount, which is a cumulative value of the amount of power consumed by the transportation device within a first period ending at the current time point, and a predicted power consumption amount, which is a predicted value of the amount of power consumed by the transportation device within a second period starting at the current time point; When the sum of the accumulated power consumption amount and the predicted power consumption amount exceeds a threshold, the operation of the transport device is controlled so as to reduce the transport capacity of the transport device. Conveying system.

2. The controller controls the operation of the transport device so as to reduce a transport speed or a transport acceleration of the package by the transport device when the sum of the accumulated power consumption amount and the predicted power consumption amount exceeds the threshold value. The transport system according to claim 1 .

3. The controller controls the operation of the transport device so as to temporarily suspend the transport of the package by the transport device when the sum of the accumulated power consumption amount and the predicted power consumption amount exceeds the threshold value. The transport system according to claim 1 .

4. When the sum of the accumulated power consumption amount and the predicted power consumption amount exceeds the threshold, the controller changes the transport process of the transport device and controls the operation of the transport device so as to reduce the transport capacity of the transport device. The transport system according to any one of claims 1 to 3.

5. The controller changes the transport process of the transport device to a transport process with a higher priority when the sum of the accumulated power consumption amount and the predicted power consumption amount exceeds the threshold value. The transport system according to claim 4 .

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