JP4419083B2 - Article conveying device - Google Patents

Description

The present invention relates to a vehicle body for conveying articles that can travel along a travel rail, a drive travel wheel that is provided on the vehicle body and rotates in contact with the travel rail, and the drive travel wheel is driven to rotate. An electric motor, and travel control means for controlling the driving power supplied to the electric motor are provided,
The travel control means drives the electric motor at a target speed determined for traveling in a form of speed increasing operation in which the vehicle body is accelerated at a set acceleration, steady traveling operation, and deceleration operation in which the vehicle body is decelerated at a set deceleration. Therefore, the present invention relates to an article conveying apparatus configured to control electric power for driving the electric motor so that the rotation speed of the electric motor becomes the target speed.

The article conveying device as described above is a stacker crane used in, for example, an automatic warehouse, and after sequentially performing speed increasing operation, steady traveling operation, and deceleration operation, the vehicle body reaches a target stop position corresponding to the target location. Then, by stopping the vehicle body, the article is conveyed to the target location.
When condensation or oil adheres to the traveling rail, the driving traveling wheel slips, causing the following inconvenience.
For example, in the speed increasing operation, the traveling speed of the vehicle body cannot be increased properly, and the time required for the speed increasing operation becomes longer, leading to a decrease in transport efficiency. In the deceleration operation, the traveling speed of the vehicle body cannot be appropriately reduced, and the vehicle body may overrun the target stop position. And if the slip of the driving traveling wheel occurs intermittently, the article placed on the vehicle body may collapse.

Therefore, in the conventional article conveying apparatus, a distance detection means for detecting the actual travel distance of the vehicle body and a distance recognition means for determining the travel distance of the vehicle body by measuring the rotational speed of the driving travel wheel are provided, and the travel control means. However, when the vehicle is traveling, it is determined whether or not the actual travel distance detected by the distance detection means differs from the travel distance calculated by the distance recognition means by a set amount or more. It is configured to correct the set acceleration in the high-speed driving and the set deceleration in the low-speed driving to be small (for example, refer to Patent Document 1).
In Patent Document 1, as a distance detection means, a vehicle-side rotary encoder in which a sprocket that rotates by traveling of a vehicle body in a state of meshing with a chain laid along a traveling rail is attached to a rotating shaft, or a traveling route of the vehicle body There is provided an optical distance measuring device that projects a beam light for distance measurement toward a reflector provided at the end of the lens and measures the distance by the reflected light.
The distance recognizing means is provided with a motor-side rotary encoder that is attached to the rotating shaft of the electric motor and detects the rotational speed of the electric motor that is the rotational speed of the driving traveling wheel, and is detected by the motor-side rotary encoder. The travel distance of the vehicle body is obtained from the rotational speed of the drive travel wheel.

JP 2002-202816 A

  In the conventional article conveying apparatus, in order to determine whether or not the driving traveling wheel is slipping, in addition to the distance detecting means, a motor-side rotary encoder must be newly attached to the rotating shaft of the electric motor. Therefore, there is a possibility that the configuration may be complicated, such as an increase in the number of members and installation work.

  The present invention has been made paying attention to such points, and an object of the present invention is to provide an article conveying apparatus capable of suppressing the occurrence of inconvenience due to slipping of the driving traveling wheel while simplifying the configuration. .

In order to achieve this object, the first characteristic configuration of the article transporting apparatus according to the present invention includes a vehicle body for transporting an article that can travel along the traveling rail, and the vehicle body that is provided on the vehicle body and contacts the traveling rail. A driving traveling wheel that rotates in rotation, an electric motor that rotationally drives the driving traveling wheel, and a traveling control unit that controls driving power supplied to the electric motor, the traveling control unit comprising: In order to drive the electric motor at a target speed that is determined in order to drive the vehicle body in the form of speed increasing operation for increasing the vehicle speed at a set acceleration, steady driving operation and decelerating operation for decelerating at a set deceleration, In the article conveying apparatus configured to control the electric power for driving the electric motor so that the rotation speed becomes the target speed,
Electric power detection means for detecting electric power for driving the electric motor is provided, and the travel control means stores an appropriate value of the electric power for driving the electric motor with respect to the rotation speed of the electric motor when performing the speed increasing operation. Then, during the execution of the speed increasing operation, it is determined whether or not the driving power detected by the power detection means is smaller than the appropriate value by a set amount. In this point, correction is made to reduce the set acceleration and the set deceleration in the deceleration operation.

That is, when the traveling control means is performing the speed increasing operation, when the rotational speed of the electric motor is a certain rotational speed, an appropriate value of the driving power for the rotational speed and the driving power detected by the power detecting means Based on the above, it is possible to determine whether or not the driving wheel is slipping by determining whether or not the driving power is smaller than the appropriate value.
In making this determination, there is provided a power detection means having a simple configuration for detecting electric power for driving the electric motor, and driving of the electric motor with respect to the rotation speed of the electric motor when the traveling control means performs the speed increasing operation. It is only necessary to store an appropriate value of the electric power, and it is possible to determine whether or not the driving traveling wheel is slipping by adding a simple configuration.
When the traveling control means determines that the driving power detected by the power detecting means is smaller than the appropriate value by a set amount, it is determined that the driving traveling wheel is slipping, and the set acceleration and deceleration in the speed increasing operation are determined. Correct the deceleration setting during operation.

  From the above, according to the present invention, it has become possible to provide an article conveying apparatus capable of suppressing the occurrence of inconvenience due to slipping of the driving traveling wheel while simplifying the configuration.

  According to a second characteristic configuration of the article transporting apparatus according to the present invention, the travel control unit detects the power detection unit when the set acceleration in the speed increasing operation and the set deceleration in the speed reduction operation are corrected to be small. The point is that the correction is made in accordance with the difference between the driving power value and the appropriate value.

In other words, the traveling control means increases when the rotational speed of the electric motor is a certain rotational speed according to the difference between the appropriate value of the driving power for the rotational speed and the driving power detected by the power detection means. It is possible to set how much the set acceleration in the high speed driving and the set deceleration in the low speed driving are corrected.
If the difference between the driving power value and the appropriate value is large, the amount of slippage of the driving traveling wheel also increases. Therefore, the set acceleration and the setting decrease are set according to the amount of slipping of the driving traveling wheel. The speed can be corrected, and the correction can be performed accurately.

  According to a third characteristic configuration of the article transporting apparatus according to the present invention, the driving control unit detects the driving detected by the power detection unit during execution of the speed increasing operation with the set acceleration corrected to be small. It is determined whether or not the electric power is larger than a reference value for increase determined with respect to the appropriate value, and when it is determined that the electric power is large, the set acceleration in the speed increasing operation and the set deceleration in the speed reducing operation are corrected to increase. The point is that it is configured to do.

That is, the slippage of the driving traveling wheel is intermittently generated depending on the conditions such as condensation on the traveling rail and adhesion of oil. If the set acceleration and the set deceleration are corrected to be small when the driving wheel is not slipping, it takes time for the vehicle body to travel to the target location, which may lead to a decrease in conveyance efficiency. is there.
Therefore, according to the present invention, when the speed increase operation is performed in a state where the set acceleration is corrected to be small, when the rotation speed of the electric motor is a certain rotation speed, the traveling control means drives the drive power at the rotation speed. Whether or not the driving power is larger than the reference value for increase is determined based on the reference value for increase determined with respect to the appropriate value and the driving power detected by the power detection means. When this is done, the set acceleration in the speed increasing operation and the set deceleration in the speed reducing operation are largely corrected, assuming that the driving traveling wheel does not slip.
As described above, when the driving traveling wheel is not slipped, the set acceleration and the set deceleration that have been corrected to be small are largely corrected, thereby suppressing the occurrence of inconvenience due to slipping of the driving traveling wheel and improving the conveyance efficiency. The decrease can be suppressed.

  According to a fourth characteristic configuration of the article transporting apparatus according to the present invention, the vehicle body is provided with a lifting platform that is movable up and down with respect to the vehicle body, and the lifting platform includes an article between itself and the article transfer location. There is an article transfer device for transferring the item.

That is, since the article transfer device is provided on a lifting platform that can be raised and lowered with respect to the vehicle body, the article can be transferred to a high place or a low place by raising or lowering the lifting board.
And since the raising / lowering platform which can be raised / lowered with respect to a vehicle body is provided, the height of a vehicle body itself will become high, and if the slip of the driving | running | working driving | running | working wheel will generate | occur | produce intermittently, possibility that a load collapse will arise will become high.

  However, as described in the first characteristic configuration, when slip occurs on the driving traveling wheel, the set acceleration and the set deceleration are corrected to be small, so that an article can be transferred to a high place or a low place while the load collapses. It has become possible to provide an article conveying apparatus that can suppress the occurrence of the above.

An example in which the article conveying apparatus according to the present invention is applied to an automatic warehouse will be described with reference to the drawings.
As shown in FIG. 1, this automatic warehouse automatically has two storage shelves 1 spaced apart so that the direction of putting in and out the goods is opposed to each other, and a traveling passage 2 formed between the storage shelves 1. A stacker crane 3 as a traveling article transporting device is provided. Each storage shelf 1 is configured by arranging a large number of article storage units 4 vertically and horizontally.

In the traveling passage 2, a traveling rail 5 is installed on the lower side along the longitudinal direction of the storage shelf 1, and a guide rail 6 is installed on the upper side along the longitudinal direction of the storage shelf 1.
On one end side of the traveling rail 5, a ground-side controller 7 that manages the operation of the stacker crane 3 and a pair of loading platforms 8 with the traveling rail 5 interposed therebetween are provided.
Each of the pair of loading platforms 8 and the multiple article storage units 4 is configured as an article transfer location K.

As shown in FIG. 2, the stacker crane 3 includes a traveling carriage 10 as a vehicle body that can travel along the traveling rail 5, and a lifting platform 12 that can be raised and lowered relative to the traveling carriage 10. A fork device 11 is provided as an article transfer device capable of transferring the pallet P on which the article 9 is placed on the lifting platform 12.
The stacker crane 3 moves the pallet P placed on the loading table 8 to the article storage unit 4 by traveling the traveling carriage 10, raising and lowering the lifting platform 12, and operating the fork device 11. The pallet P stored in the article storage unit 4 is configured to be transferred to the loading table 8.

The lifting platform 12 is supported and supported by a pair of front and rear lifting masts 13 erected on the traveling carriage 10 so as to be movable up and down, and is suspended and supported by lifting chains 14 connected to the left and right sides thereof. It has become.
The elevating chain 14 is wound around a guide sprocket 16 provided on the upper frame 15 guided along the guide rail 6 and a guide sprocket 17 provided on one elevating mast 13. It is connected to an equipped take-up drum 18.
The take-up drum 18 is driven to rotate forward and backward by an elevating electric motor 19 that is an inverter type motor, and the elevating platform 12 is moved up and down by the feeding and winding operations of the elevating chain 14. Yes.

The traveling carriage 10 has an elevation laser range finder 20 for projecting ranging beam light in the horizontal direction, and a path of the beam light projected by the elevation laser range finder 20 vertically upward. A mirror 22 is provided for bending and irradiating the reflecting plate 21 installed on the lower surface of the lifting platform 12.
The lifting laser range finder 20 detects the distance between the reference position and the lifting platform 12 in the lifting direction of the lifting platform 12 with the position of the mirror 22 provided on the traveling carriage 10 as the reference position. By this, it is comprised so that the raising / lowering position of the raising / lowering stand 12 on an raising / lowering path | route may be detected.

The traveling carriage 10 is provided with two front and rear traveling wheels 23 that can travel on the traveling rail 5, and one of the two traveling wheels 23 on one end side in the vehicle body front-rear direction is an inverter type motor. The driving wheel 23a is driven by a driving electric motor 24 as an electric motor, and the driving wheel on the other end side in the longitudinal direction of the vehicle body is configured as a freely driven driven wheel 23b. Yes.
Then, the traveling carriage 10 travels along the traveling rail 5 by rotating the driving traveling wheel 23 a by the operation of the traveling electric motor 24.

Further, a traveling laser range finder 25 for projecting a distance measuring beam light in the horizontal direction is provided at the end of the traveling rail 5 on the ground controller 7 side. A reflecting plate 26 for reflecting the beam light from the rangefinder 25 is provided.
Then, the traveling laser range finder 25 projects toward the reflecting plate 26 installed on the traveling carriage 10 and detects the distance of the traveling carriage 10 from the end of the traveling rail 5, thereby causing the traveling route. The traveling position of the traveling carriage 10 is detected.

As shown in FIG. 3, the stacker crane 3 is provided with a crane control device 27 that receives an entry / exit command from the ground-side controller 7 and controls the operation of the stacker crane 3.
The crane control device 27 is configured to receive detection information of the lifting laser range finder 20 and detection information of the traveling laser range finder 25.

The crane control device 27 includes an elevating control unit 27a that performs elevating control for elevating the elevating platform 12 to a commanded elevating target stop position based on detection information of the elevating laser rangefinder 20, and a traveling laser range finder. 25, a travel control unit 27b that performs travel control for traveling the travel cart 10 to the commanded target stop position for travel, and a transfer control that performs transfer control for operating the fork device 11 to transfer the article 9. The loading control unit 27c and the like are included.
Then, the crane control device 27 issues a warehousing command for warehousing the article 9 on the loading table 8 into the article storage unit 4, an unloading command for unloading the article 9 stored in the article storage unit 4 to the loading table 8, and the like. When receiving from the side controller 7, the lifting control by the lifting control unit 27 a, the traveling control by the traveling control unit 27 b, and the transfer control by the transfer control unit 27 c are performed, and the article 9 on the loading table 8 is stored in the article storage unit 4. The warehousing process is performed, and the article 9 stored in the article storage unit 4 is output to the loading unit 8.

Hereinafter, the traveling control by the traveling control unit 27b will be described.
The travel control unit 27b travels in such a manner as to perform a speed-up operation in which the traveling vehicle 10 is accelerated at a set acceleration, a steady-state travel operation in which the travel speed is maintained while maintaining the travel speed, and a deceleration operation in which the speed is decelerated at a set deceleration. In order to drive the traveling electric motor 24 at a target speed determined in (1), the driving electric power of the traveling electric motor 24 is controlled so that the rotational speed of the traveling electric motor 24 becomes the target speed.
The travel control means W that controls the drive current as the drive power supplied to the travel electric motor 24 includes a travel control unit 27 b and a travel inverter 28. The travel inverter 28 is configured to input a drive current of the travel electric motor 24 to the travel control unit 27b and to act as power detection means.

The traveling control unit 27b is configured to manage the traveling position of the traveling carriage 10 and the traveling speed of the traveling carriage 10 on the traveling route based on the detection information of the traveling laser rangefinder 25.
Then, when traveling the traveling cart 10 to travel to the target article transfer location K, the traveling control unit 27b, first, based on the traveling distance between the current position of the traveling vehicle 10 and the target stop position for traveling, FIG. As shown, it is configured to set a travel speed curve that defines a target speed.
Incidentally, the travel target stop position is a position corresponding to the target article transfer location K among the plurality of article transfer locations K, and this information is received from the ground-side controller 7. .

  The traveling control unit 27b gives the driving output value of the traveling electric motor 24 to the traveling inverter 28 so that the traveling speed of the traveling carriage 10 changes according to the traveling speed curve after the traveling starts. However, the driving current supplied to the traveling electric motor 24 is controlled so as to be the driving output value from the traveling control unit 27b.

To explain the travel speed curve, the travel control unit 27b first performs a speed-up operation for increasing the travel speed to the set travel speed with the set acceleration α, and then travels. A steady traveling operation is performed in which the vehicle travels while maintaining the speed, and then a deceleration operation is performed in which the vehicle is decelerated at a set deceleration β from the set traveling speed to a low traveling speed (creep speed) for stopping.
Then, the traveling control unit 27b allows the traveling position of the traveling carriage 10 obtained from the detection information of the traveling laser rangefinder 25 to reach the traveling target stop position during traveling at the low traveling speed (creep speed). Then, the supply of the drive current to the travel electric motor 24 is stopped and the brake is applied to stop the travel cart 10 at the travel target stop position.

The set acceleration α, the set travel speed, the set deceleration β, and the low travel speed for stop are set in advance.
Then, the traveling control unit 27b obtains the timing for switching from the speed increasing operation to the steady traveling operation or the timing for switching from the steady traveling operation to the deceleration operation depending on the traveling distance, and sets the traveling speed curve as shown in FIG. It is configured.

As described above, the traveling control unit 27b sequentially performs the speed increasing operation, the steady traveling operation, and the deceleration operation, and then stops the traveling carriage 10 at the traveling target stop position. If the driving traveling wheel 23a slips due to condensation or the like, various inconveniences may occur in a speed increasing operation or a speed reducing operation.
For example, in the speed increasing operation, the traveling speed of the traveling carriage 10 cannot be increased appropriately, and the time required for the speed increasing operation becomes longer, leading to a decrease in transport efficiency. In the deceleration operation, the traveling speed of the traveling carriage 10 cannot be appropriately reduced, and the vehicle body may overrun the target stop position. Further, if the driving traveling wheel 23a slips intermittently, the article 9 of the traveling carriage 10 may collapse.

  Therefore, the traveling control unit 27b monitors the driving current of the traveling electric motor 24 during traveling to determine whether or not the driving traveling wheel 23a is slipped. When the vehicle slips, the set acceleration α in the speed increasing operation and the set deceleration β in the speed reducing operation are corrected to suppress the occurrence of the inconvenience as described above.

As shown in FIG. 5, the traveling control unit 27b stores an appropriate value P of the driving current for the traveling electric motor 24 with respect to the rotational speed of the traveling electric motor 24 when the speed increasing operation is performed.
Then, the traveling control unit 27b determines whether or not the driving current D input from the traveling inverter 28 is smaller than the appropriate value P by a set amount R during execution of the speed increasing operation, and the driving traveling wheel 23a. It is determined whether or not slip has occurred.
When the driving control unit 27b determines that the driving current D is smaller than the appropriate value P by the set amount R, the driving control unit 27b assumes that slip has occurred in the driving driving wheel 23a, and the set acceleration α in the speed increasing operation and in the decelerating operation. Correction is made to reduce the set deceleration β.

In other words, the traveling control unit 27b receives an appropriate value P for the rotational speed of the traveling electric motor 24 at that time and the traveling inverter 28 every time the set time elapses during execution of the speed increasing operation. To determine whether or not the difference | P−D | is greater than the set amount R.
Then, as illustrated in FIG. 5A, the traveling control unit 27b determines that the driving current D is smaller than the appropriate value P when the difference | P−D | is larger than the set amount R.

As described above, when the traveling control unit 27b determines that the driving current D is smaller than the appropriate value P by the set amount R, the set acceleration α in the speed increasing operation is changed to the corrected acceleration set amount as shown by a one-dot chain line in FIG. Correction is made smaller by T1, and the set deceleration β in the deceleration operation is corrected smaller by the correction deceleration set amount T2.
At this time, the traveling control unit 27b sets the set acceleration α in the speed increasing operation and the setting decrease in the speed reducing operation according to the difference | P−D | between the appropriate value P and the driving current D input from the driving inverter 28. The speed β is corrected to be small.
That is, the traveling control unit 27b increases the correction acceleration setting amount T1 and the correction deceleration setting amount T2 as the difference | P−D | increases, and increases as the difference | P−D | increases. And the set deceleration β in the deceleration operation is corrected so as to be small.

  In this way, after correcting the set acceleration α in the speed increasing operation and the set deceleration β in the speed reducing operation to be small, the travel control unit 27b adjusts the travel cart 10 according to the travel speed curve shown by the one-dot chain line in FIG. The drive output value of the traveling electric motor 24 is given to the traveling inverter 28 so that the traveling speed changes.

In addition, the travel control unit 27b not only corrects the set acceleration α and the set deceleration β to be small, but also confirms that no slip has occurred in the drive travel wheel 23a, the set acceleration α and the set deceleration β. Is greatly corrected.
That is, the traveling control unit 27b determines whether or not the driving current D input from the traveling inverter 28 is larger than the increase reference value Q during execution of the speed increasing operation with the set acceleration α corrected to be small. When it is determined that the speed is large, the set acceleration α-T1 in the speed increasing operation and the set deceleration β-T2 in the speed reducing operation are corrected to increase.

In other words, the travel control unit 27b causes the drive current D input from the travel inverter 28 to be larger than the increase reference value Q determined for the rotational speed at that time each time the set time elapses. It is determined whether or not.
The increase reference value Q is larger than a value that is smaller than the appropriate value P by a set amount R with respect to the appropriate value P of drive power determined for the rotational speed of the traveling electric motor 24. The travel control unit 27b stores the increase reference value Q.
Then, as shown in FIG. 5B, when the driving current D becomes larger than the increase reference value Q, the traveling control unit 27b sets the set acceleration α− in the speed increasing operation as shown by the solid line in FIG. T1 is largely corrected by the correction acceleration set amount T1, and the set deceleration β-T2 in the deceleration operation is largely corrected by the correction deceleration set amount T2, and the set acceleration α and the set deceleration β before the small correction are corrected. Return to.

  In this way, the traveling control unit 27b corrects the set acceleration α in the speed increasing operation and the set deceleration β in the speed reducing operation based on the driving current D of the traveling electric motor 24 during the speed increasing operation. Thus, the articles are conveyed while suppressing the inconvenience caused by the slip of the driving traveling wheel 23a and not reducing the conveyance efficiency.

[Another embodiment]
(1) In the above embodiment, when the traveling control unit 27b determines that the driving current D is smaller than the appropriate value P by the set amount R, the set acceleration α in the speed increasing operation and the set deceleration β in the speed reducing operation are corrected to be small. However, as indicated by the dotted line in FIG. 4, in addition to the set acceleration α in the speed increasing operation and the set deceleration β in the speed reducing operation, the set travel speed in the steady driving operation may be corrected to be small.

(2) In the above embodiment, when the traveling control unit 27b corrects the set acceleration in the speed increasing operation and the set deceleration in the speed reducing operation to a small value, the driving power detected by the power detecting means and the appropriate value Although the correction is performed according to the difference, it is possible to appropriately change how small the set acceleration in the speed increasing operation and the set deceleration in the speed reducing operation are corrected.

(3) In the above embodiment, the driving current is exemplified as the driving power, but the driving voltage can be applied.

(4) In the above embodiment, when detecting the traveling position of the traveling carriage 10 on the traveling path and the lifting position of the lifting platform 12 on the lifting path, the traveling laser range finder 25 and the lifting laser range finder 20 However, for example, a rotary encoder that can be rotated along with the traveling of the traveling carriage 10 and the raising / lowering of the lifting platform 12 is provided, and the traveling position of the traveling carriage 10 on the traveling route and the lifting platform 12 on the lifting route are provided. It is also possible to detect the ascending / descending position, and various sensors can be applied.

(5) In the above embodiment, a stacker crane having the traveling carriage 10 as a vehicle body is exemplified as the article conveying device according to the present invention. However, for example, there are various types such as an autonomous traveling type article conveying vehicle having an article conveying vehicle as a vehicle body. The present invention can be applied to other article conveying apparatuses.

Perspective view of automated warehouse Side view of stacker crane Control block diagram of stacker crane Graph showing traveling speed curve A graph showing the relationship between the rotational speed of the electric motor for traveling and the current value

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Travel rail 10 Car body for goods conveyance 11 Goods transfer apparatus 12 Elevator 23a Driving wheel 24 Electric motor 28 Electric power detection means K Goods transfer location W Travel control means

Claims (4)

A vehicle body for conveying articles that can travel along the travel rail, a drive travel wheel that is provided on the vehicle body and rotates in contact with the travel rail, and an electric motor that rotationally drives the drive travel wheel; Travel control means for controlling the driving power supplied to the electric motor is provided,
The travel control means drives the electric motor at a target speed determined for traveling in a form of speed increasing operation in which the vehicle body is accelerated at a set acceleration, steady traveling operation, and deceleration operation in which the vehicle body is decelerated at a set deceleration. Therefore, an article conveying apparatus configured to control electric power for driving the electric motor so that a rotation speed of the electric motor becomes the target speed,
A power detection means for detecting power for driving the electric motor is provided;
The travel control means stores an appropriate value of electric power for driving the electric motor with respect to the rotational speed of the electric motor when the speed increasing operation is performed, and the power detection means is configured to execute the speed increasing operation. It is determined whether or not the driving power detected in this way is smaller than the appropriate value by a set amount. When it is determined that the driving power is smaller, the set acceleration in the speed increasing operation and the set deceleration in the speed reducing operation are corrected to be small. Article conveying apparatus configured as described above.   When the travel control means corrects the set acceleration in the acceleration operation and the set deceleration in the deceleration operation to be small, according to the difference between the driving power detected by the power detection means and the appropriate value The article conveying apparatus according to claim 1, wherein the article conveying apparatus is configured to correct.   The travel control means is configured to increase the reference value for the driving power detected by the power detection means with respect to the appropriate value during execution of the speed increasing operation with the set acceleration corrected to be small. It is discriminate | determined whether it is larger, and when it determines that it is larger, it is comprised so that it may correct | amend so that the setting acceleration in the said acceleration driving | operation and the setting deceleration in the said deceleration driving | operation may be enlarged. Article transport device. The vehicle body is provided with a lifting platform that can be raised and lowered relative to the vehicle body,
The article transfer apparatus according to any one of claims 1 to 3, wherein the lifting platform is provided with an article transfer device for transferring an article between itself and an article transfer location.

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