JP4399737B2 - Article transfer device - Google Patents

Description

The present invention provides a moving body that moves to a plurality of article transfer locations, a transfer means that is provided on the movable body and transfers articles between itself and the article transfer location, and the transfer means An article presence / absence detection sensor for detecting whether or not an article is present at the article transfer location, and a control means for controlling the operation of the moving body and the transfer means.
When the control means is requested to wholesale the article to any of the plurality of article transfer locations, the control means is configured to move the movable body to a target stop position corresponding to the article transfer location. After controlling the operation, in order to transfer the article to the article transfer location, the operation of the transfer means is controlled, and the article is transferred to the article transfer location based on the detection information of the article presence / absence detection sensor. The present invention relates to an article transfer device configured to execute a transfer process for controlling the operation of the transfer means so as to stop the operation of the transfer means when there is an error.

The article transfer device as described above can pick up an article from one of a plurality of article transfer locations, or wholesale an article to one of a plurality of article transfer locations, thereby Articles are transported between them.
When an article is wholesaled to any of a plurality of article transfer locations, it is determined whether or not an article already exists at the article transfer location based on detection information of the article presence / absence detection sensor. When an article is present at the transfer location, the article transfer is stopped to prevent collision between articles.
Thus, the determination of whether or not an article is present at the article transfer location is performed based on the detection information of the article presence / absence detection sensor. It is impossible to accurately determine whether or not an article exists.

  Therefore, in the conventional article transfer device, when inspection of the article presence / absence detection sensor is requested, the control means applies to an article transfer location in an in-stock state among the plurality of article transfer locations. The operation of the moving body is controlled to move the moving body to one detectable position where the article presence / absence detecting sensor can detect the article, and the article presence / absence detecting sensor When the presence cannot be detected, a sensor abnormality determination process for determining an abnormality of the article presence / absence detection sensor is executed (for example, see Patent Document 1).

JP 2003-341806 A

  In the conventional article transfer device, if the article presence / absence detection sensor can detect the presence of an article at one detectable position, the article presence / absence detection sensor is determined to be normal. However, for some reason, the article presence / absence detection sensor may erroneously detect the presence of the article, and there is a possibility that the abnormality of the article presence / absence detection sensor cannot be accurately determined.

  The present invention has been made paying attention to such a point, and an object thereof is to provide an article transfer device capable of accurately determining an abnormality of an article presence / absence detection sensor.

In order to achieve this object, a first characteristic configuration of an article transfer device according to the present invention includes a mobile body that moves to a plurality of article transfer locations, and the mobile body that is provided in the mobile body, Transfer means for transferring an article to and from the place, an article presence / absence detection sensor provided in the transfer means for detecting whether or not an article is present at the article transfer place, the moving body, and Control means for controlling the operation of the transfer means is provided, and the control means corresponds to the article transfer location when it is required to wholesale the article to any of the plurality of article transfer locations. After the operation of the moving body is controlled to move the moving body to the target stop position, the operation of the transfer means is controlled to transfer the article to the article transfer location, and the presence / absence of the article Based on the detection information of the detection sensor, the article is transferred to the article transfer location. In order to stop operation exists and the transfer means, the article transfer device that is configured to perform a transfer process for controlling the operation of said transfer means,
When the inspection of the article presence / absence detection sensor is requested, the control means determines the presence / absence of the article from the plurality of article transfer places with respect to an article transfer place in which an article exists. In order to move the movable body to a plurality of detectable positions that can be detected by the detection sensor, the operation of the movable body is controlled, and the article presence / absence detection sensor is located at one of the plurality of detectable positions. When the presence cannot be detected, a sensor abnormality determination process for determining an abnormality of the article presence / absence detection sensor is performed.

  That is, when the inspection of the article presence detection sensor is requested, the control means executes a sensor abnormality determination process, and at a plurality of detectable positions, the article presence / absence detection sensor detects the article at the article transfer location in the loaded state. If the article presence detection sensor can detect the presence of the article at all of the plurality of detectable positions, the article presence / absence detection sensor determines that the article is normal and detects the plurality of detectable positions. If at least one of the article presence / absence detection sensors cannot detect the presence of an article, the article presence / absence detection sensor determines that there is an abnormality.

  In this way, if the article presence / absence detection sensor cannot detect the presence of an article even at one of a plurality of detectable positions, the article presence / absence detection sensor determines that the article is abnormal. Even if the presence is erroneously detected, it is unlikely that this erroneous detection will occur at all of the plurality of detectable positions, so that the abnormality of the article presence / absence detection sensor can be accurately determined.

  And if the moving body is moved over a plurality of detectable positions, it takes time for the sensor abnormality determination process, but the plurality of detectable positions are positions with respect to the same article in the article transfer location in the stock state. Therefore, the moving distance of the moving body can be shortened as much as possible, and the time required for the sensor abnormality determination process can be shortened as much as possible.

  From the above, according to the present invention, it has become possible to provide an article transfer apparatus that can determine the abnormality of the article presence / absence detection sensor accurately while shortening the time required for the determination as much as possible.

  The second characteristic configuration of the article transfer device according to the present invention is a stop that allows the transfer means to appropriately transfer the article to and from the article transfer location on the basis of the target stop position. In the transfer process, the control means controls the operation of the moving body to move the moving body within the stop allowable range, and in the sensor abnormality determination process, The plurality of positions within the allowable stop range are set as the plurality of detectable positions so that the operation of the moving body is controlled.

That is, since the control means controls the operation of the moving body in order to move the moving body within the stop allowable range in the transfer process, after the mobile body is positioned within the stop allowable range, Thus, the article can be properly wholesaled to the article transfer location while detecting the presence or absence of the article.
And in the sensor abnormality determination process, the control means controls the operation of the moving body with a plurality of positions within the stop allowable range as a plurality of detectable positions, so the same stop as when the article is unloaded at the article transfer location It is possible to determine whether or not the article presence / absence detection sensor is abnormal by positioning the moving body within the allowable range.
Therefore, when an article is wholesaled, it is possible to determine whether or not the article presence / absence detection sensor is abnormal within a tolerable stop range in which the article presence / absence detection sensor is actually used. Can do.

  According to a third characteristic configuration of the article transfer device according to the present invention, the article transfer location is each storage section in an article storage shelf provided with a plurality of storage sections arranged vertically and horizontally, and the movable body moves horizontally. In addition, it is provided so as to be movable up and down.

That is, an article can be stored in each of the plurality of storage units in the article storage shelf as an article transfer location, and more articles can be stored while reducing the installation space of the article storage unit as much as possible.
Then, the moving body moves horizontally and moves up and down and is positioned at one of a plurality of target stop positions corresponding to each of the plurality of storage units, thereby transferring the article between the mobile body and the storage unit. It can be performed.
In this way, while the article can be stored in the plurality of storage units, the moving body is moved to a plurality of detectable positions with respect to any of the storage units in which the article is stored, It is possible to determine whether or not the article presence / absence detection sensor is abnormal, and a useful article transfer apparatus is obtained.

An embodiment in which an article transfer device 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 includes two article storage shelves 1 that are installed at an interval so that the article loading and unloading directions are opposed to each other, and a traveling path 2 that is formed between the article storage shelves 1. And a stacker crane 3 as an article transfer device that automatically travels.

Each article storage shelf 1 has a plurality of a pair of front and rear support columns 1a standing in the left-right direction, and each pair of front and rear support columns 1a has a mounting support portion 1b extending in the left-right direction spaced in the vertical direction. A plurality are provided apart.
A pair of front and rear support columns 1a and a pair of left and right mounting support portions 1b form a single storage portion 4, and a plurality of the storage portions 4 are arranged side by side.

A traveling rail 5 is installed along the longitudinal direction of the article storage shelf 1 on the lower side of the traveling passage 2, and a guide rail 6 is installed along the longitudinal direction of the article storage shelf 1 on the upper side. .
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 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 that can travel along the traveling rail 5, and a lifting platform 12 that can move up and down with respect to the traveling carriage 10. Is provided with a fork device 11 as a transfer means capable of transferring the article 9 to and from the article transfer location K.
The stacker crane 3 can be moved to a plurality of article transfer locations K by traveling of the traveling carriage 10 and raising and lowering of the elevator platform 12, and a moving body that moves to the plurality of article transfer locations K is provided with the traveling carriage 10 and It is composed of a lifting platform 12.

As shown in FIG. 3, the fork device 11 is, for example, a three-stage fork device including a base 11a, a secondary fork 11b, and a primary fork 11c. An article presence / absence detection sensor 28 for detecting whether or not the article 9 is present at the article transfer location K is provided at the leading end portion of the primary fork 11c.
The article presence / absence detection sensor 28 is, for example, a light projecting / receiving type, and as shown by a dotted line in FIG. 3, when the article 9 exists at the article transfer location K, the light projected from the light projecting unit is emitted. Reflection by the article 9 and reception of the reflected light by the light receiving unit detect that the article 9 is present at the article transfer location K.

As shown in FIG. 2, 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 freely move up and down. It is supported by hanging.
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 in the forward and reverse directions by an elevating electric motor 19 that is an inverter type motor, and the elevating platform 12 is moved up and down by a feeding operation and a winding operation of the elevating chain 14. ing.

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.

Further, the traveling carriage 10 is provided with two front and rear wheels 23 that can travel on the traveling rail 5, and one of the two wheels 23 at one end in the vehicle body front-rear direction is an inverter type motor. A driving wheel 23a for propulsion driven by an electric motor 24 for traveling as an electric motor is configured, and a wheel on the other end side in the longitudinal direction of the vehicle body is configured as a freely driven wheel 23b.
The traveling carriage 10 is configured to travel along the traveling rail 5 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. 4, the stacker crane 3 is provided with a crane control device 27 as a control means for controlling the operation of the stacker crane 3 based on a command from the ground controller 7.
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 a travel control unit 27 a that controls the travel of the traveling carriage 10, a lift control unit 27 b that controls the lift of the lift platform 12, a transfer control unit 27 c that controls the operation of the fork device 11, and the like. ing.
Then, the crane control device 27 stores the article 9 stored in any of the plurality of storage units 4 or the loading instruction for storing the article 9 of the load mounting table 8 in any of the plurality of storage units 4. When an exit command or the like is issued from the ground-side controller 7, the operation of entering the article 9 of the loading table 8 into the commanded storage unit 4 or the article 9 stored in the commanded storage unit 4 is loaded. It is comprised so that the unloading operation | movement which leaves to the mounting part 8 may be performed.

The ground-side controller 7 instructs the crane controller 27 to set a target travel stop position, a scooping target lift stop position, and a wholesale target lift stop position for the target article transfer location K, together with a warehousing command and a shipping command. It is configured.
Then, the crane control device 27 executes a transfer process for scooping up the articles 9 on the loading table 8 in the warehousing operation, and then executes a transfer process for wholesales the articles 9 in the warehousing operation. After carrying out a transfer process for picking up any of the articles 9 in the plurality of storage units 4, a transfer process for wholesale the articles 9 on the loading table 8 is executed.

The target travel stop position, the scooping target lift stop position, and the wholesale target lift stop position are determined corresponding to each of a plurality of article transfer locations K such as the pair of loading platforms 8 and the plurality of storage units 4. It has been.
The scooping target lifting / lowering stop position is set to a position that is lower than the mounting support section 1b of the storage section 4 or the mounting section of the load mounting table 8 by a set height. A position higher than the placement support portion 1b and the placement portion of the load placement table 8 by a set height is determined.

The transfer process for scooping will be described.
The crane control device 27 controls the operation of the stacker crane 3 to move the stacker crane 3 to the target travel stop position and scooping target lifting stop position corresponding to the target article transfer location K, and then the article transfer. The operation of the stacker crane 3 is controlled in order to pick up the article 9 from the location K.

  In other words, first, the traveling control unit 27a controls the operation of the traveling electric motor 24 so that the traveling carriage 10 travels to the target traveling stop position based on the detection information of the traveling laser rangefinder 25. Based on the detection information of the lifting laser rangefinder 20, the lifting control unit 27b controls the lifting electric motor 19 to lift and lower the lifting platform 12 to the scooping target lifting stop position based on the detection information of the lifting laser rangefinder 20. Elevating and lowering control is performed.

At this time, with reference to the target travel stop position, a travel stop allowable range in which the fork device 11 can appropriately perform the article transfer to and from the article transfer location K is determined, and the scooping target lift stop position Also for the above, a lifting / lowering allowable range based on the scooping target lifting / stopping position is defined.
Therefore, in the travel control, the traveling carriage 10 is stopped within the allowable travel stop range, and in the up / down control, the lift platform 12 is stopped within the allowable lift stop range.

When the traveling carriage 10 stops within the travel stop allowable range and the lift platform 12 stops within the lift stop allowable range, the transfer control unit 27c causes the fork to protrude below the article 9 at the article transfer location K. Therefore, after the fork device 11 is operated to project, the elevating control unit 27b controls the operation of the elevating electric motor 19 to elevate the elevating platform 12 by the set height.
In this way, by raising the elevator 12 with the fork device 11 protruding, the article 9 at the article transfer location K is picked up, and finally, the transfer control unit 27c removes the fork from the elevator 12 The fork device 11 is retired so as to be retired.

The wholesale transfer process will be described.
The crane control device 27 controls the operation of the stacker crane 3 to move the stacker crane 3 to the target travel stop position and the wholesale target lifting stop position corresponding to the target article transfer location K, and then the article transfer. The operation of the stacker crane 3 is controlled to wholesale the article 9 at the location K, and the stacker crane 3 is activated when the article 9 exists at the target article transfer location K based on the detection information of the article presence / absence detection sensor 28. In order to stop the operation, the operation of the stacker crane 3 is controlled.

In other words, like the transfer process for scooping, first, the traveling control unit 27a performs traveling control, and the lifting control unit 27b performs lifting control, so that the traveling carriage 10 is placed at the target traveling stop position. The elevator 12 is moved up and down to the wholesale target lift stop position.
At this time, the wholesale target lift stop position, like the scooping target lift stop position, is defined as a lift stop allowable range, so in the lift control, the lift platform 12 is stopped within the lift stop allowable range, and In the traveling control, the traveling carriage 10 is stopped within the traveling stop allowable range.

Then, as shown in FIG. 3 (a), when the lifting platform 12 stops within the lifting stop allowable range and the traveling carriage 10 stops within the traveling stop allowable range, the transfer control unit 27c causes the article transfer location K to move. The fork device 11 is operated to project so that the fork on which the article 9 is placed is projected to the upper side.
The transfer control unit 27c detects the presence / absence of the article presence / absence detection sensor 28 when the lifting platform 12 stops within the lifting stop allowable range and when the traveling carriage 10 stops within the traveling stop allowable range or during the protrusion operation of the fork device 11. Based on the detection information, it is determined whether or not the article 9 exists at the target article transfer location K.
Then, as shown by the dotted line in FIG. 3 (a), the transfer control unit 27c stops the operation of the fork device 11 and abnormally causes the stacker crane 3 to malfunction when there is an article 9 at the target article transfer location K. Stop.

In addition, when the article 9 does not exist at the target article transfer location K, the transfer control unit 27c continues the protruding operation of the fork device 11 as shown in FIG. When the protrusion operation is completed, the elevating control unit 27b controls the operation of the elevating electric motor 19 so as to lower the elevating table 12 by the set height.
In this way, by lowering the lifting platform 12 in a state where the fork device 11 on which the article 9 is placed is protruded, the article 9 is wholesaled to the article transfer location K, and finally, the transfer control unit 27c In order to retract the fork to the lifting platform 12, the fork device 11 is retracted.

  When executing the wholesale transfer process, if the article presence / absence detection sensor 28 is abnormal, it cannot be accurately determined whether or not the article 9 exists in the target article transfer location K. Therefore, when the inspection of the article presence / absence detection sensor 28 is requested, the crane control device 27 is configured to execute a sensor abnormality determination process for determining whether or not the article presence / absence detection sensor 28 is abnormal.

  In other words, when the inspection of the article presence / absence detection sensor 28 is requested, the crane control device 27 determines that, among the plurality of article transfer locations K, the article transfer location K in which the article 9 is present, The operation of the stacker crane 3 is controlled to move the stacker crane 3 to a plurality of detectable positions that can be detected by the article presence / absence detection sensor 28, and the presence / absence detection of the article is detected at any of the plurality of detectable positions. When the sensor 28 cannot detect the presence of the article, a sensor abnormality determination process for determining that the article presence / absence detection sensor 28 is abnormal is executed.

The inspection request of the article presence / absence detection sensor 28 is instructed to the crane control unit 27 from the ground side controller 7 by human operation, or automatically when the operating time of the sutter crane 3 reaches the set time. The controller 7 can instruct the crane control unit 27.
Further, when the crane control device 27 is not instructed to enter or leave, it is possible to automatically execute the sensor abnormality determination process, and how to request inspection of the article presence / absence detection sensor 28. The configuration of can be changed as appropriate.

The ground-side controller 7 manages the storage status of the article storage shelf 1 such as which storage section 4 of the plurality of storage sections 4 stores the article 9, and the storage status that is managed Based on the plurality of article transfer locations K, the crane control device 27 is commanded to the article transfer location K in a stock state.
The crane control device 27 moves the stacker crane 3 to a plurality of detectable positions with respect to the article 9 existing in the commanded article transfer location K in the in-stock state. The operation of the stacker crane 3 is controlled by setting the positions as a plurality of positions within a stop allowable range that is a combination of the travel stop allowable range and the lift stop allowable range at the article transfer location K in the loaded state.

In addition, as shown in FIG. 5, the allowable stop range P is a range in which the horizontal center position is the target travel stop position and the vertical center position is the wholesale target lifting stop position, Within the permissible stop range P, five positions of the center position T1, the upper left corner position T2, the lower left corner position T3, the lower right corner position T4, and the upper right corner position T5 are defined as detectable positions.
Then, the travel control unit 27a travels so as to change the position where the article presence / absence detection sensor 28 detects the article 9 in the order of the center position T1, the upper left corner position T2, the lower left corner position T3, the lower right corner position T4, and the upper right corner position T5. Control is performed and the lift control unit 27b performs lift control.

When the transfer control unit 27c detects the article 9 by the article presence / absence detection sensor 28 at all of the center position T1, the upper left corner position T2, the lower left corner position T3, the lower right corner position T4, and the upper right corner position T5. Then, it is determined that the article presence / absence detection sensor 28 is normal.
Further, the transfer control unit 27c cannot detect the article 9 by the article presence / absence detection sensor 28 even at one of the center position T1, the upper left corner position T2, the lower left corner position T3, the lower right corner position T4, and the upper right corner position T5. Is determined that the article presence / absence detection sensor 28 is abnormal.

[Another embodiment]
(1) In the above embodiment, in the sensor abnormality determination process, five within the stop allowable range P, that is, the center position T1, the upper left corner position T2, the lower left corner position T3, the lower right corner position T4, and the upper right corner position T5 can be detected. Although it is set as a position, it is possible to appropriately change which position in the stop allowable range P is a detectable position, and also in what order the stacker crane 3 is moved in the order of the plurality of positions. Is possible.

(2) In the above embodiment, in the sensor abnormality determination process, a plurality of positions within the allowable stop range P are set as a plurality of detectable positions. However, the plurality of detectable positions are the article transfer locations K in a loaded state. As long as it is a position where the same article 9 can be detected, it is not limited to the stop allowable range P.

(3) In the above embodiment, when detecting the traveling position of the traveling carriage 10 on the traveling path and the raising / lowering position of the lifting platform 12 on the lifting path, the traveling laser rangefinder 25 and the lifting laser rangefinder 20 are detected. 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.

(4) In the above embodiment, as an article transfer device according to the present invention, a stacker crane having the traveling carriage 10 and the lifting platform 12 as moving bodies has been exemplified, but for example, an autonomous traveling article having a vehicle body as a moving body. The present invention can be applied to various article transfer devices such as a transport vehicle.

Schematic perspective view of automated warehouse Side view of stacker crane The figure which shows a fork apparatus and an article storage shelf Automatic warehouse control block diagram The figure which shows the several detectable position in a sensor abnormality discrimination | determination process

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Goods storage shelf 4 Storage part 9 Goods 10,12 Moving body 11 Transfer means 27 Control means 28 Goods presence detection sensor K Goods transfer location T1-T5 Detectable position

Claims (3)

A moving body that moves to a plurality of article transfer locations, a transfer means that is provided on the mobile body and that transfers articles between itself and the article transfer location, and is provided on the transfer means An article presence / absence detection sensor for detecting whether or not an article is present at the article transfer location, and a control means for controlling the operation of the moving body and the transfer means,
When the control means is requested to wholesale the article to any of the plurality of article transfer locations, the control means is configured to move the movable body to a target stop position corresponding to the article transfer location. After controlling the operation, in order to transfer the article to the article transfer location, the operation of the transfer means is controlled, and the article is transferred to the article transfer location based on the detection information of the article presence / absence detection sensor. An article transfer device configured to execute a transfer process for controlling the operation of the transfer means in order to stop the transfer means when it is present,
When the inspection of the article presence / absence detection sensor is requested, the control means determines the presence / absence of the article from the plurality of article transfer places with respect to an article transfer place in which an article exists. In order to move the movable body to a plurality of detectable positions that can be detected by the detection sensor, the operation of the movable body is controlled, and the article presence / absence detection sensor is located at one of the plurality of detectable positions. An article transfer apparatus configured to execute a sensor abnormality determination process for determining that an abnormality of the article presence / absence detection sensor is detected when the presence cannot be detected. With reference to the target stop position, a stop allowable range in which the transfer means can appropriately perform the article transfer with the article transfer location is determined,
The control means controls the operation of the moving body in order to move the moving body within the stop allowable range in the transfer process, and a plurality of the stop allowable range in the sensor abnormality determination process. The article transfer apparatus according to claim 1, wherein the position of the plurality of positions is set as the plurality of detectable positions and the operation of the moving body is controlled. The article transfer location is each storage section in an article storage shelf provided with a plurality of storage sections arranged vertically and horizontally,
The article transfer apparatus according to claim 1, wherein the movable body is provided so as to be movable in a horizontal direction and in a vertically movable manner.

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