JP6834852B2 - Stacker crane - Google Patents

Description

The present invention relates to a stacker crane used for transporting goods in an automated warehouse facility or the like.

In equipment that manages a large number of goods, such as automated warehouse equipment, stacker cranes are used as goods transport devices for moving goods inside the equipment and for loading and unloading goods between the outside and inside of the equipment. May be used.

Patent Document 1 discloses a stacker crane as a physical distribution device that automatically stores and discharges goods from a goods storage shelf for storing goods. This stacker crane is provided with a traveling carriage that runs on the floor of the equipment and an elevating platform that can be raised and lowered. By the traveling operation of the traveling carriage and the raising and lowering operation of the lifting platform, the vertical and horizontal directions in the article storage shelf Articles are transferred between the storage units and the lifts arranged in each of the above.

Patent Document 1 shows that the traveling speed is lowered from the rating when the traveling operation is expected to be completed before the elevating operation. By performing such control, in the stacker crane of Patent Document 1, the power saving of the stacker crane is achieved by preventing the traveling bogie from waiting in a stopped state until the lifting operation of the lifting table is completed.

Japanese Unexamined Patent Publication No. 2012-076858

However, with the conventional stacker crane as described above, even if the total power consumption over the entire period from the start to the completion of the traveling operation and the elevating operation can be reduced, a part of the total period is reduced. In a specific period, the total of the power consumption of the traveling operation and the power consumption of the lifting operation may temporarily exceed the rating.

If both the power for the traveling operation and the power for the lifting operation are supplied from the main power source of the stacker crane in common, the main power supply is the power consumption of the traveling operation and the power consumption of the lifting operation. The total power consumption that is the total must be output. On the other hand, each of the traveling operation and the elevating operation has a period from the start to the completion where the power consumption is highest, that is, the maximum peak period of the power consumption. Here, considering the possibility that the traveling operation and the elevating operation are performed at the same time and these maximum peak periods overlap, the power corresponding to the total value of the maximum power consumption of both the traveling operation and the elevating operation can be supplied. A main power supply with a high rating (high maximum output power) is required.

To solve this problem, a method of mounting a storage battery on a stacker crane as an auxiliary power source to assist the main power supply and assisting the power supply during the maximum peak period by using the power stored in advance from the main power source in this storage battery. Can be considered. With this method, the rating of the main power supply does not have to be very high. However, there is an upper limit to the power that can be output from the storage battery, and if the upper limit power that can be output is actually output from the storage battery each time (many times), the life of the storage battery may be shortened. Therefore, it is desirable that the total power consumption is always lower than the upper limit power that can be output from the storage battery during the entire period from the start to the completion of the traveling operation and the elevating operation. Similarly, the main power supply is also overloaded when the maximum power that can be output is actually output, so it is desirable that the total power consumption be as low as possible even at the peak.

Therefore, in the present invention, the power consumption required for the operation of the stacker crane is reduced to save power, and the total power consumption is excessive even when the power consumption peak for traveling and the power consumption peak for ascending / descending overlap. Try not to get high.

In order to solve the above problems, the stacker crane as an example of the embodiment according to the present invention is a stacker crane used for transporting an article, and travels along a traveling path by being driven by a traveling motor. A traveling trolley that moves in the horizontal direction, an elevating pedestal that moves in the vertical direction along the elevating mast erected on the traveling trolley by moving up and down by the drive of an elevating motor, and the above-mentioned according to an external transport instruction. In a stacker crane having a moving control device for moving the lifting table to a target position specified by a transport instruction by controlling a traveling motor and the lifting motor, the movement control device is the lifting table. The drive pattern of the traveling motor and the elevating motor required to move the motor from the current position to the target position is determined according to a predetermined standard control rule, and the drive pattern determined according to the standard control rule. In the case where the maximum peak period of the power consumed by the traveling motor and the maximum peak period of the power consumed by the elevating motor overlap in the drive pattern determined according to the standard control rule, the movement is performed. The control device determines the drive pattern of the traveling motor and the elevating motor according to a power saving control rule in which the upper limit speed of the traveling motor and the elevating motor is set lower than the upper limit speed in the standard control rule. It is characterized by that.

Further, in a further embodiment of the present invention, the stacker crane is provided with a power storage device that stores electric power supplied from the main power source, and does the power storage device output electric power jointly with the main power source? Or, by outputting the electric power from only the power storage device, it is possible to output higher power than when the power is output only from the main power source, and the traveling motor and the elevating / lowering from the power storage device. It is preferable that power for driving is supplied to the motor.

Further, in a further embodiment of the present invention, in the stacker crane, the standard control rule includes a standard upper limit traveling speed as an upper limit of the traveling speed of the traveling vehicle and a standard as an upper limit of the ascending / descending speed of the lifting platform. When the upper limit elevating speed is preset and the movement control device determines the drive pattern of the traveling motor and the elevating motor according to the standard control rule, the movement control device is the traveling carriage. Is the shortest running time required to travel to the horizontal coordinates of the target position at the standard upper limit running speed, and the shortest lifting time required for the lifting platform to move up and down to the vertical coordinates of the target position at the standard upper limit lifting speed. , And when the shortest traveling time is longer than the shortest ascending / descending time, the elevating table takes the same time as the shortest traveling time for the elevating table to move up and down to the vertical coordinates of the target position. When the ascending / descending speed is set and the minimum ascending / descending time is longer than the minimum traveling time, the traveling vehicle takes the same time as the minimum ascending / descending time to travel to the horizontal coordinates of the target position. It is preferable to set the traveling speed of the traveling carriage.

Further, in a further embodiment of the present invention, in addition to setting the traveling speed of the traveling vehicle as described above, the maximum power required for the lifting platform to move up and down the maximum distance that can be raised and lowered as fast as possible. And time are defined as the maximum lifting power and the maximum distance lifting time, respectively, and the maximum power required for the traveling vehicle to travel at the standard upper limit traveling speed for the same period as the maximum distance lifting time is defined as the maximum traveling power. A value equal to or greater than the sum of the maximum traveling power and the maximum traveling power is set as the power saving threshold value, and when the drive patterns of the traveling motor and the elevating motor are determined according to the standard control rule, the traveling motor and the elevating motor are determined. When the peak of the total power consumed by the motor is larger than the power saving threshold, it is preferable that the movement control device determines the drive pattern of the traveling motor and the elevating motor according to the power saving control rule. ..

According to the stacker crane as an example of the embodiment according to the present invention, the upper limit speed of the elevating motor is low when the power consumption peak for traveling and the power consumption peak for elevating overlap according to the standard control rules. Since the set power saving control rules are used, the upper limit of the power consumption of the elevating motor is limited to a low level, and the power consumption peak for running and the power consumption peak for elevating overlap. However, the total power consumption, which is the sum of the power consumption for running and the power consumption for raising and lowering, does not become excessively high. In addition, by using the power saving control rules, the periods of power consumption peaks for running and ascending / descending may be shifted. In this case, these peaks do not overlap as a result, and thus the total power consumption can be kept low. ..

Further, in a further embodiment, if the stacker crane is provided with a power storage device such as a storage battery and the power storage device can output high power that can sufficiently assist the main power source, the rating is small (output is possible). If it is necessary to use a main power source (which has a low maximum power), for example, even if the main power source installed in the equipment cannot be changed, the stacker crane with high power consumption can be operated without any problem. Even in this case, as described above, the total power consumption does not become excessively high, so that it is possible to avoid actually outputting power high enough to reach the upper limit that the power storage device can output, and the life of the power storage device. Will not shrink. More specifically, it is preferable that the power output from only the power storage device or the power output jointly by the power storage device and the main power supply is larger than the power output from only the main power supply.

Further, according to the stacker crane in the further embodiment, by setting the traveling speed or the ascending / descending speed according to the comparison between the shortest traveling time and the minimum ascending / descending time, the ascending / descending of the elevating table and the traveling of the traveling carriage are completed at the same time. Therefore, it is possible to prevent a situation in which either one of the lift and the traveling carriage waits for the completion of the operation of the other in a stopped state.

Further, according to the stacker crane in a further embodiment, the peak of the total power consumption is the maximum permissible in the standard control rule by setting a value equal to or more than the sum of the maximum hoisting power and the maximum traveling power as the power saving threshold. It is easy to switch to the power saving control rule when the power is expected to be exceeded.

FIG. 3 is a perspective view of an automated warehouse facility having a stacker crane as an example of an embodiment of the present invention. The block diagram of the automated warehouse equipment of FIG. The flowchart of the processing performed in the automated warehouse equipment of FIG. Flow chart of drive pattern determination process. The graph which shows the speed transition of a traveling bogie and an elevator in a drive pattern according to a standard control rule, and the power consumption transition of each motor. The graph which shows the speed transition of a traveling bogie and an elevator in a drive pattern according to a power saving control rule, and the power consumption transition of each motor.

Hereinafter, a stacker crane as an example of the embodiment according to the present invention will be described. FIG. 1 shows an example of an automated warehouse facility 10 including a stacker crane 20. The automated warehouse facility 10 is provided with an article storage shelf 50, and the stacker crane 20 carries in and out the article 14 to the article storage shelf 50 while traveling in the automated warehouse facility 10. Further, the automated warehouse facility 10 is provided with an automated warehouse controller 60 that manages the work performed in the facility. The automated warehouse controller 60 manages information on each article 14 and outputs a transport instruction to the stacker crane 20, for example. The automated warehouse controller 60 can be automatically operated according to a predetermined routine, but it is managed by receiving an operation instruction from an administrator (such as a logistics company) of the automated warehouse equipment 10 via an input device 62. It can also operate according to the instructions of the person. FIG. 1 shows a touch panel display provided in the main body of the automated warehouse controller 60 as an example of the input device 62.

The article storage shelf 50 is provided with a plurality of columns and a plurality of storage portions 52 individually separated by a pair of arms 54. As shown in FIG. 1, a plurality of these storage portions 52 are arranged in each of the vertical direction (vertical direction) and the horizontal direction (horizontal direction) in the article storage shelf 50, and each of them can store the article 14.

A plurality of article storage shelves 50 are provided in the automated warehouse facility 10. Although two article storage shelves 50 are shown in FIG. 1, the article storage shelves 50 on the front side are omitted except for the end portion in order to make the stacker crane 20 easy to see. The automated warehouse controller 60 provides information about each storage unit 52 of the article storage shelf 50, such as which storage unit 52 belongs to which article storage shelf 50, which position in the horizontal direction, and which position in the vertical direction. Based on the above, each of the storage units 52 is individually identified and managed.

The plurality of article storage shelves 50 are arranged at intervals so that the articles 14 are taken in and out of the storage section 50 so as to face each other, and the stacker crane 20 runs between the article storage shelves 50.

The stacker crane 20 includes a traveling carriage 22 and an elevating platform 23. The traveling carriage 22 is guided by a traveling rail 28 arranged on the floor surface side along the longitudinal direction (horizontal direction) of each article storage shelf 50 and a guide rail 29 arranged parallel to the traveling rail 28 on the ceiling side. Then, it moves in the horizontal direction along the traveling path defined by the traveling rail 28. A traveling motor 22M (FIG. 2) (not shown in FIG. 1) is provided on the traveling carriage 22, and the traveling carriage 22 travels by driving the traveling motor 22M to rotate the wheels.

The lift 23 is supported and guided by a pair of front and rear lift masts 27 erected on the traveling carriage 22. By driving a lifting motor 23M (FIG. 2) (not shown in FIG. 1), for example, a chain that is wound around a sprocket provided on the lifting mast 27 and suspends the lifting table 23 is wound up and unwound. , The lift 23 moves in the vertical direction along the lift mast 27. By traveling the traveling carriage 22 and raising and lowering the lifting platform 23, the lifting platform 23 can be moved to a position facing an arbitrary storage portion 52 in the article storage shelf 50. The lifting platform 23 can be raised and lowered while the traveling carriage 22 is traveling, and the lifting platform 23 can change its horizontal position and vertical position at the same time.

Further, the elevating table 23 is provided with a fork device 24 (transfer device) capable of moving the elevating table 23 in and out in the direction from the stacker crane 20 toward the storage unit 52 (direction in which the article 14 is taken in and out). By operating the fork device 24, it is possible to transfer articles between the lifting platform 23 and the article storage shelf 50. For example, the transfer operation is performed by expanding and contracting the foldable arm in the loading / unloading direction by driving a transfer motor 24M (FIG. 2) (not shown in FIG. 1). It should be noted that the actual transfer involves not only driving the transfer motor 24M but also raising and lowering the lifting platform 23. That is, when the arm is extended, the elevating table 23 is located in the article storage shelf 50, and in that state, the elevating table 23 is located below the storage portion 52 that stores the article 14 (between the pair of arms 54). Ascending (through), the article 14 stored in the storage section 52 is carried out by the fork device 24. On the other hand, when the elevating table 23 on which the article 14 is placed descends from above the empty storage section 52, the article 14 mounted on the elevating table 23 is carried into the storage section 52.

A crane controller 25 that controls the operation of the stacker crane 20 is provided on the root side of one of the pair of elevating masts 27. As shown in FIG. 2, the crane controller 25 moves up and down with a communication device 38 that communicates with the automated warehouse controller 60 (wireless communication such as infrared communication and radio wave communication, or wired communication), and a traveling carriage 22. A movement control device 30 that controls the movement of the table 23 and the like are included.

FIG. 2 is a block diagram showing a relationship between various devices provided in the automated warehouse facility 10. As shown in FIG. 2, the movement control device 30 included in the crane controller 25 includes a traveling control unit 32 that controls the traveling motor 22M, an elevating control unit 33 that controls the elevating motor 23M, and a transfer motor 24M. It has a transfer control unit 34 for controlling the above.

Further, the traveling control unit 32 and the elevating control unit 33 measure the horizontal measuring device 32a for measuring the current position (horizontal position) of the traveling vehicle 22 and the current position (vertical position) of the elevating table 23, respectively. The measured current position information is received from the vertical measuring device 33a. As a specific example of the horizontal measuring device 32a, a laser measuring method in which a laser beam is projected from the traveling carriage 22 in parallel with the traveling rail 28 and the reflected light from a reflector (not shown) provided at the end of the traveling rail 28 is examined. Measuring instruments are available. Similarly, for the vertical measuring device 33a, a laser measuring device that projects laser light upward from the base portion of the traveling carriage 22 and examines the reflected light from the reflector attached to the bottom surface side of the lifting platform 23 is available. It is available. As a result, the movement control device 30 can recognize the horizontal position of the traveling carriage 22 and the vertical position of the lifting platform 23, and can notify the position to the automated warehouse controller 60 via the communication device 38. it can.

Further, as shown in FIG. 2, the automated warehouse facility 10 is provided with a main power source 70 and a power storage device 72. As the main power source 70, for example, a commercial power source can be used, and the operating power of various devices such as the automated warehouse controller 60 and the crane controller 25 is supplied from the main power source 70. However, from the viewpoint of safety and cost, the power that can be output instantaneously by the main power supply 70 is often limited, and the peak power is used for a device that consumes a large amount of power such as a motor. It may not be possible to supply stably. Therefore, in the block diagram shown in FIG. 2, a power storage device 72 (capacitor or storage battery) for storing the electric power supplied from the main power source 70 is provided, and the traveling motor 22M, the elevating motor 23M, and the transfer motor 24M are provided. On the other hand, electric power is supplied from the power storage device 72. It is preferable that the power storage device 72 is constructed so that it can instantaneously output more power than the main power source 70 by storing (charging) the power in advance. The main power supply 70 is also connected to each motor through the crane controller 25, and it is possible to supply power to each motor from the main power supply 70. However, when the required power momentarily increases, the power storage device By assisting the power supply by 72, it is possible to stably supply power to each motor even if the main power supply 70 has an output limit.

When the movement control device 30 receives an instruction (transportation instruction from the outside) from the automated warehouse controller 60 to move the elevating table 23 to a specific target position (a position facing any storage unit 52), the traveling trolley Based on the current positions of the 22 and the lift 23, the control is executed so that the traveling carriage 22 travels and the lift 23 moves up and down at an appropriate speed transition.

The processing performed in the automated warehouse facility 10 will be described with reference to the flowchart shown in FIG. First, an automated warehouse requests from the input device 62 or an external higher-level device to newly store the article 14 in the article storage shelf 50 (import request) or to take out the stored article 14 from the article storage shelf 50 (unload request). It is input to the controller 60. Alternatively, the automated warehouse controller 60 automatically generates a carry-in request or a carry-out request according to a predetermined routine as to how each article 14 should be managed. Then, when a carry-in request occurs, the automated warehouse controller 60 searches for a storage unit 52 (empty storage unit 52) capable of storing the article 14 based on the information of each storage unit 52 managed, and either of them. The empty storage unit 52 of the above is determined as the storage destination of the article 14. On the other hand, when a carry-out request is made, the storage unit 52 in which the target article 14 is stored is determined as the take-out source of the article 14. Once the storage destination or take-out source storage unit 52 is determined, it is based on information on which article storage shelf 50 the storage unit 52 belongs to, which position in the horizontal direction, and which position in the vertical direction. , A transport instruction including information on the target position where the elevator 23 should finally move is transmitted to the crane controller 25 via the communication device 38 (step S01).

The movement control device 30 of the crane controller 25 moves the elevating table 23 to the target position based on the target position included in the transport instruction and the current position of the elevating table 23 measured by the horizontal measuring device 32a and the vertical measuring device 33a. What kind of speed transition should the traveling crane 22 and the lifting platform 23 move in order to move (acceleration motion, constant velocity motion, and deceleration motion, respectively, for how long and at what acceleration or speed? The drive pattern of the traveling motor 22M and the elevating motor 23M is determined according to a predetermined standard control rule (step S02).

The movement control device 30 inspects the determined drive pattern again to confirm whether the maximum peak period of the electric power consumed by the traveling motor 22M and the maximum peak period of the electric power consumed by the elevating motor 23M do not overlap. (Step S03). If the maximum peak periods of both do not overlap, the traveling motor 22M and the elevating motor 23M are driven according to the driving pattern determined according to the standard control rule (step S04). On the other hand, when the maximum peak periods of both are overlapped, the drive pattern determined according to the standard control rule is discarded, and the drive pattern is redetermined according to the predetermined power saving control rule (step S05). In this power saving control rule, the upper limit speed of the elevating motor 23M is set lower than the upper limit speed in the standard control rule. After that, the traveling motor 22M and the elevating motor 23M are driven according to the driving pattern determined according to the power saving control rule (step S06). After the completion of step S04 or step S06, the lift 23 reaches the target position. After that, the movement control device 30 executes a transfer operation for the storage unit 52 (step S07). That is, the transfer motor 24M (and the elevating motor 23M) is driven to carry the article 14 into the storage section 52, or the article 14 is carried out from the storage section 52.

The movement control device 30 of the crane controller 25 performs the above-mentioned processing each time a transport instruction based on a carry-in request or a carry-out request is transmitted, and executes the loading and unloading of the article 14 to the article storage shelf 50.

The process when the drive pattern is determined in step S02 described above will be described with reference to the flowchart of FIG. In the standard control rules, in consideration of the performance limit of the equipment and the stability of operation, the standard upper limit traveling speed vam as the upper limit of the traveling speed v of the traveling carriage 22 and the upper limit of the ascending / descending speed vb of the elevator 23 are set. The standard upper limit elevating speed vbm of is set in advance.

In determining the drive pattern, first, the horizontal distance La to be traveled by the traveling vehicle 22 is calculated from the horizontal coordinates of the target position and the horizontal coordinates of the current position of the elevator 23 included in the transport instruction, and the horizontal distance La is determined. The shortest running time ta0 required to run at the standard upper limit running speed vam is calculated (step S21). In this calculation, the traveling vehicle 22 does not travel at a constant standard upper limit traveling speed vam, but the time and distance required to accelerate from the stopped state to the standard upper limit traveling speed vam, and the stopped state from the standard upper limit traveling speed vam. The time and distance required to decelerate to is also taken into account.

Next, the vertical distance Lb that the lift 23 should move up and down is calculated from the vertical coordinates of the target position and the vertical coordinates of the current position of the lift table 23 included in the transport instruction, and the vertical distance Lb is used as the standard upper limit lift speed vbm. The shortest ascending / descending time tb0 required for ascending / descending is calculated (step S22). In this calculation as well, the time and distance required for the elevating platform 23 to accelerate from the stopped state to the standard upper limit ascending / descending speed vbm, and the time and distance required for decelerating from the standard upper limit elevating speed vbm to the stopped state are taken into consideration.

Then, the calculated shortest running time ta0 and the shortest ascending / descending time tb0 are compared (step S23). As a result of comparison, when the shortest traveling time ta0 is longer than the shortest ascending / descending time tb0 (ta0> tb0), the one expected to complete the movement earlier, that is, the speed of the elevating platform 23 is limited. That is, the ascending / descending speed vb is set lower than the standard upper limit elevating speed vbm (vb <vbm), and the time tb required to move the vertical distance Lb is adjusted to be the same as the shortest traveling time ta0 (tb = ta0). (Step S24).

On the other hand, when the shortest ascending / descending time tb0 is longer than the shortest traveling time ta0 (ta0 <tb0), the speed of the traveling carriage 22 is limited. That is, the traveling speed va is set to a value (va ≦ vam) equal to or less than the standard upper limit traveling speed vam so that the time ta required to move the horizontal distance La is the same as the shortest ascending / descending time tb0 (ta = tb0). It is adjusted (step S25).

When the shortest traveling time ta0 and the shortest ascending / descending time tb0 are the same (ta0 = tb0), the traveling carriage 22 and the elevating platform 23 may be moved at the standard upper limit traveling speed vam and the standard upper limit elevating speed vbm, respectively. In FIG. 4, for convenience of illustration, when ta0 = tb0, the same processing as in step S25 is performed (as a result of the processing, va = vam is set).

By setting the traveling speed va and the ascending / descending speed vb as described above, the traveling operation and the ascending / descending operation are adjusted to be completed at the same time while minimizing the time required for the movement of the elevating table 23.

FIG. 5 shows an example of the speed transition of the traveling carriage 22 and the lifting platform 23 when the traveling motor 22M and the elevating motor 23M are driven by the driving pattern according to the standard control rule as described above, and the power consumption transition of each motor. Shown.

The peak period of speed and the peak period of power consumption do not always match. However, the greater the speed to be finally reached, the longer the period of acceleration and deceleration must be, or the greater the acceleration and deceleration forces, so the speed to be finally reached (set running speed va). And the higher the ascending / descending speed vb), the longer the peak period of power consumption and the larger the peak value tend to be.

As a result of performing the processing shown in FIG. 4, the traveling operation and the elevating operation are adjusted so as to be completed in the same time. However, since the traveling speed va and the ascending / descending speed vb are different values, and the horizontal distance La and the vertical distance Lb to be moved are also different values, as shown in FIG. 5, the length of the peak period of the speed (rotation speed) is The traveling motor 22M and the elevating motor 23M are different. However, regarding the peak periods of power consumption of both motors, these peak periods partially overlap in the drive pattern shown in FIG.

In FIG. 5, as an example, the power consumption peak value of the traveling motor 22M is 160 kW, and the power consumption peak value of the elevating motor 23M is 70 kW. Assuming that the upper limit (recommended upper limit) of the electric power that the power storage device 72 shown in FIG. 2 can supply together with the main power source 70 without shortening the life is 200 kW, if the traveling motor 22M operates alone, it can be operated without any problem. However, as shown in FIG. 5, when the peak periods of the power consumption of the traveling motor 22M and the elevating motor 23M overlap, the power consumption of 230 kW is instantaneously required, so that the main power supply 70 and the power storage device 72 It exceeds the recommended upper limit of. Even if the required power consumption exceeds the recommended upper limit, the power source 70 and the power storage device 72 can actually supply the power exceeding the recommended upper limit, so that the stacker crane 20 does not stop operating, but the recommended upper limit is set. If the excess power is supplied, the life of the power storage device 72 will be shortened.

In this case, it is desirable to create a drive pattern in accordance with the power saving control rules so that the total power consumption is within 200 kW at the maximum. The graph shown in FIG. 6 is a drive pattern according to the power saving control rule.

Regarding the procedure for determining the drive pattern in the power saving control rule, basically, except that the upper limit speed of the lifting motor 23M is set lower than the upper limit speed (standard upper limit lifting speed vbm) in the standard control rule. The same procedure as in FIG. 4 can be used. That is, the upper limit speed of the elevating motor 23M in the power saving control rule is set to the power saving upper limit elevating speed vbz (vbz <vbm), and the power saving upper limit elevating speed vbz is used instead of the standard upper limit elevating speed vbm in FIG. Should be decided.

Since the power saving upper limit lifting speed vbz is lower than the standard upper limit lifting speed vbm, the peak period and peak value when accelerating from the stopped state to the power saving upper limit lifting speed vbz are smaller than when the standard upper limit lifting speed vbm is used. Become. Therefore, as shown in FIG. 6, the portion where the peak periods of the traveling motor 22M and the elevating motor 23M overlap is small, and the total power consumption of both motors can be suppressed to a low level even at the overlapping portion. As a specific example, assuming that the power consumption peak value of the elevating motor 23M becomes 40 kW as a result of setting the upper limit elevating speed vbz low in the power saving control rule, the consumption of the traveling motor 22M (peak 160 kW) and the elevating motor 23M. Even if the peak periods of electric power overlap, the instantaneous power consumption is 200 kW or less at the maximum, so that the recommended upper limit of the main power source 70 and the power storage device 72 is not exceeded. Therefore, the life of the power storage device 72 does not have to be shortened.

As described above, in the stacker crane 20 of the present embodiment, the traveling carriage 22 and the lifting platform 23 are appropriately operated so as to reach the target position in the shortest possible time, and the life of the power storage device 72 is controlled so as not to be shortened. Therefore, high transport efficiency and a long maintenance-free period are realized.

As for how to determine in the calculation that the peak periods of power consumption of the traveling motor 22M and the elevating motor 23M overlap in the standard control rule, a graph as shown in FIG. 5 is actually created. Then, the degree of overlap of the peak periods may be investigated, but the transition of the total power consumption (instantaneous total power consumption) consumed by the traveling motor 22M and the elevating motor 23M is calculated, and the peak sets a predetermined threshold value. A simple judgment may be made based on whether or not the value is exceeded.

In other words, the power saving threshold is set as the reference value that "if the total power consumption exceeds this value even momentarily, the power saving control rule is applied", and the maximum value of the expected total power consumption and the power saving threshold are set. Can be compared with. Here, as the value of the power saving threshold value, the above-mentioned recommended upper limit (a predetermined value peculiar to the automated warehouse equipment 10) may be used as it is. Further, the power saving threshold value may be determined by calculation based on the power consumed in the actual operation of the stacker crane 20.

The following procedure can be considered as an example of the method of determining the power saving threshold value by calculation. First, the maximum distance that the lift 23 can move up and down is confirmed. The maximum distance that can be raised and lowered is the size of the range in which the lifting platform 23 can move vertically along the mast 27. In many cases, this distance corresponds to the distance between the uppermost storage portion 52 and the lowermost storage portion 52 of the article storage shelf 50. How long (maximum distance elevating time) is required to elevate this maximum elevating distance at the highest possible speed (for example, standard upper limit elevating speed vbm), and what value of maximum power consumption is required during that time. Calculate whether it becomes (maximum lifting power). Then, with respect to the calculated maximum distance ascending / descending time, it is calculated how much power consumption (maximum traveling power) becomes when the traveling carriage 22 travels at the standard upper limit traveling speed vam for the same period. The sum of the maximum lifting power and the maximum running power calculated in this way is set as the power saving threshold value. Here, if it is desired to increase the number of cases to which the standard control rule is applied, a value somewhat larger than the sum of the maximum hoisting power and the maximum traveling power may be set as the power saving threshold value.

Explaining the above-mentioned calculation of the power saving threshold in detail, the electric power that can be supplied by the main power source 70 and the power storage device 72 basically moves independently for the maximum distance assumed by the traveling carriage 22 and the elevator 23. Since the power consumption is set higher than the power consumption, the power saving threshold value may be set to a higher value. On the other hand, if it is attempted to move in a short distance in the shortest time, it is necessary to complete acceleration / deceleration in a short time, and the load associated with acceleration / deceleration may become excessively high. Therefore, even if the elevating distance of the elevating table 23 is shorter than the maximum distance, the peak of power consumption may become excessively high. Similarly, even when the traveling carriage 22 travels a short distance, the power consumption peak may become excessively high. Therefore, the maximum value of the power consumption when the traveling carriage 22 and the lifting platform 23 move the maximum possible distance is calculated, and the main power source 70 and the power storage device 72 can supply electric power up to that value. It may be considered that a value higher than that is set as the power saving threshold value.

In the above-described embodiment, it is determined whether or not the peak periods of the power consumption of both motors overlap after the drive pattern of the standard control rule is created. However, the combination of the horizontal distance La and the vertical distance Lb to be moved is determined. It may be decided whether to use the standard control rule or the power saving control rule based on the above. To explain in detail, since the drive pattern is determined by a fixed procedure, it is uniquely determined according to the horizontal distance La and the vertical distance Lb to be moved. Therefore, it is possible to investigate in advance by calculation what kind of combination of horizontal distance La and vertical distance Lb causes the peak periods of power consumption of both motors to overlap in the drive pattern of the standard control rule. Therefore, a table (table) showing the correspondence between the combination of the horizontal distance La and the vertical distance Lb and the standard control rule or the power saving control rule should be created by the manager of the automated warehouse equipment 10. The mobile control device 30 may refer to the table to determine whether to use the standard control rule or the power saving control rule. In this way, when the power saving control rule should be used, the procedure of once creating the drive pattern of the standard control rule and then discarding it becomes unnecessary, so that the appropriate drive pattern can be determined quickly. ..

Further, in the above-described embodiment, in order to prevent one of the traveling carriage 22 and the lifting platform 23 from waiting for the completion of the operation of the other in a stopped state, the traveling time of the traveling carriage 22 and the lifting platform The traveling speed va and the ascending / descending speed vb are adjusted so as to match the ascending / descending time of 23, but this adjustment is not always necessary. That is, if the traveling carriage 22 or the lifting platform 23 is allowed to stand by in a stopped state, the traveling carriage 22 and the lifting platform 23 can be moved at the highest possible speed (for example, at the standard upper limit traveling speed vam and the standard upper limit lifting speed vbm). ) You may move it. In particular, when it is required to transport the article 14 at high speed even if the life of the power storage device 72 is shortened due to a work delay, etc., the article 14 can be moved up and down with the traveling carriage 22 at high speed without considering power saving. The table 23 may be moved.

Further, in the above-described embodiment, the stacker crane 20 is provided with a fork device 24 for transferring the article 14 between the stacker crane 20 and the article storage shelf 50. The device for performing such transfer. Does not necessarily have to be provided on the stacker crane 20. That is, a transfer device for transferring the article 14 between the stacker crane 20 and the article storage shelf 50 may be provided on the side of the article storage shelf 50.

Further, in the above-described embodiment, the touch panel display provided in the automated warehouse controller 60 itself is shown as the input device 62 of the automated warehouse controller 60, but the input device 62 may be separate from the automated warehouse controller 60. For example, it may be a remote controller that transmits an operation instruction to the automated warehouse controller 60 by wireless communication, or a network device that transmits an operation instruction from the outside of the automated warehouse equipment 10 via an electronic network.

10 Automatic warehouse equipment 14 Goods 20 Stacker crane 22 Traveling trolley 23 Lifting platform 22M Traveling motor 23M Lifting motor 30 Movement control device 50 Goods storage shelf 52 Storage unit 60 Automatic warehouse controller 70 Main power supply 72 Power storage device

Claims (2)

A stacker crane used to transport goods
A traveling trolley that moves horizontally along the traveling path by traveling by driving a traveling motor,
An elevating platform that moves in the vertical direction along the elevating mast erected on the traveling carriage by ascending and descending by driving an elevating motor.
A movement control device that moves the elevating table to the target position instructed by the transport instruction by controlling the traveling motor and the elevating motor in response to a transport instruction from the outside.
In a stacker crane with
The movement control device determines the drive pattern of the traveling motor and the elevating motor required to move the elevating table from the current position to the target position according to a predetermined standard control rule.
When the maximum peak period of the electric power consumed by the traveling motor and the maximum peak period of the electric power consumed by the elevating motor overlap in the drive pattern determined according to the standard control rule, the movement control device Determines the drive pattern of the traveling motor and the elevating motor according to the power saving control rule in which the upper limit speed of the traveling motor and the elevating motor is set lower than the upper limit speed in the standard control rule .
In the standard control rule, a standard upper limit traveling speed as an upper limit of the traveling speed of the traveling carriage and a standard upper limit elevating speed as an upper limit of the ascending / descending speed of the elevating platform are preset.
When the movement control device determines the drive pattern of the traveling motor and the elevating motor according to the standard control rule,
The movement control device is
The shortest running time required for the traveling vehicle to travel to the horizontal coordinates of the target position at the standard upper limit traveling speed, and the shortest time required for the lifting platform to move up and down to the vertical coordinates of the target position at the standard upper limit lifting speed. Compare with the ascending / descending time,
When the shortest traveling time is longer than the shortest ascending / descending time, the ascending / descending speed of the elevating table is set so that the elevating platform takes the same time as the shortest traveling time to ascend / descend to the vertical coordinates of the target position. And
When the shortest ascending / descending time is longer than the shortest traveling time, the traveling speed of the traveling carriage is set so that the traveling carriage takes the same time as the shortest ascending / descending time to travel to the horizontal coordinates of the target position. And
The maximum power and time required to raise and lower the maximum distance that the elevator can move up and down as fast as possible are defined as the maximum lifting power and the maximum distance raising and lowering time, respectively.
The maximum power required for the traveling bogie to travel at the standard upper limit traveling speed for the same period as the maximum distance ascending / descending time is defined as the maximum traveling power.
A value equal to or greater than the sum of the maximum hoisting power and the maximum traveling power is set as the power saving threshold value.
In the drive pattern determined according to the standard control rule, when the peak of the total power consumed by the traveling motor and the elevating motor becomes larger than the power saving threshold value, the movement control device is subjected to the power saving control rule. A stacker crane, characterized in that the drive patterns of the traveling motor and the elevating motor are determined according to the above. A power storage device that stores the power supplied from the main power supply is provided.
The power storage device outputs power jointly with the main power source, or outputs power from only the power storage device to output higher power than when power is output only from the main power source. Is possible,
The stacker crane according to claim 1, wherein power for driving is supplied from the power storage device to the traveling motor and the elevating motor.

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