JP2000272712A - Elevating and carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an elevating and carrying device capable of more precisely specifying the elevation position of an elevator. SOLUTION: A elevating and carrying device is equipped with an elevator 4 provided with a commodity transfer device LT for loading up and down commodities, an elevation driving means 15 for driving the feed of a rope 16 for hanging and supporting the elevator 4, an operating amount detecting means for detecting the feed amount of the rope 16 driven by the elevation driving means 15 and an elevation control means for controlling the elevation driving means in accordance with the information detected by the operating amount detecting means. It is provided with an elevation position detecting means PS for detecting the elevation position of the elevator 4, the elevation control means correcting the information detected by the operating amount detecting means with the change amount of the elevation position, when the commodity transfer device LT loads up and down the commodities, to control the elevation driving means 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevating body which is provided with an article transfer device and is capable of loading and unloading articles, an elevating drive means for feeding and driving a cord-shaped body for suspending and supporting the elevating body, and Elevating transport provided with an operation amount detecting means for detecting a feed driving amount of the cord-like body by the elevating driving means, and an elevating control means for controlling the elevating driving means based on detection information of the operating amount detecting means. Related to the device.

[0002]

2. Description of the Related Art In such a lifting and lowering transport device, a lifting and lowering body provided with an article transfer device is driven up and down by lifting and lowering driving means to lift and lower and transport an article. The lifting and lowering of the elevating body is performed by suspending and supporting the elevating body with a cord-like body and feeding and driving the cord-like body bidirectionally by a lifting / lowering driving means. For stopping the vertical movement at the set position, conventionally, the vertical position of the vertical body is specified by the detection information of the operation amount detecting means for detecting the feed drive amount of the cord-like body by the vertical driving means, and the vertical position is stopped at a desired position. The elevation control means controls the elevation drive means so as to cause the movement.

[0003]

However, in the above-mentioned conventional construction, the cord-like body is elongated by use for a long period of time, and an error occurs in the elevation position of the elevation body specified only by the detection information of the operation amount detecting means. I will. For this reason, the lifting body is provided with a rotating member that comes into contact with a lifting guide member on the ground side and rotates as the lifting body moves up and down, and a rotary encoder that detects the rotation amount of the rotating member. If the actual vertical position detected by the detection information of the rotary encoder deviates from the target vertical position when the robot is moved up and down, a technique for correcting the deviation has been considered. By such correction, it is possible to cope with steady elongation of the cord, but it is not possible to cope with fluctuation of the elevating position due to elastic expansion and contraction of the cord, and an error may occur in specifying the elevating position. Was. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ascending / descending transport device capable of specifying the ascending / descending position of an elevating body with higher accuracy.

[0004]

According to the first aspect of the present invention, the lifting control means detects the feed amount of the cord by the lifting drive means based on the detection information of the operation amount detection means. The lifting / lowering driving means is controlled, and in accordance with the loading / unloading operation of the articles by the article transfer device, the detection information of the operation amount detecting means is corrected and the lifting / lowering body is raised / lowered. That is, the load of the elevating body changes due to the loading and unloading of the articles by the article transfer device, and the cord-like body also slightly elastically expands and contracts accordingly. Therefore, the error of the elevating position caused by the expansion and contraction is corrected. For this purpose, lifting / lowering position detecting means for detecting an actual lifting / lowering position of the lifting / lowering body is provided, and the lifting / lowering control means performs the operation of loading / unloading the articles by the article transfer device based on the detection information of the lifting / lowering position detecting means. The detection information of the operation amount detecting means is corrected based on the change amount of the elevating position at that time, and the elevating drive means is controlled. As a result, it is possible to provide an ascending / descending transport device capable of specifying the ascending / descending position of the elevating body with higher accuracy.

[0005] In addition, with the configuration according to the second aspect, an article transfer device is constituted by a slide fork type transfer device. When the article transfer device is configured in this way, when loading and unloading the articles, the slide fork-type transfer apparatus is moved up and down while the projecting operation is performed, and during the elevating movement, the articles are moved from the fork. Deliver the goods to the transfer target side, or scoop the goods from the transfer target side with a fork. Therefore, the cable-like body expands and contracts due to a change in the load of the article while the elevating body is being lifted and lowered in a state where the article is being protruded for loading and unloading the article.

Therefore, when the slide fork type transfer device is to be retracted to perform normal lifting and lowering conveyance, a normal lifting and lowering mode for controlling the lifting and lowering driving means based on the detection information of the operation amount detecting means is used. In the state where the slide fork type transfer device is operated to protrude for loading and unloading articles, the above-described normal lifting and lowering The elevating body is moved up and down by switching from the mode to the transfer elevating mode in which the elevating drive means is controlled based on the detection information of the elevating position detecting means for detecting the actual elevating position of the elevating body. Therefore, while raising and lowering the lifting body stably,
The elevating body can be raised and lowered at the time of loading and unloading articles with higher accuracy.

In addition, with the configuration according to the third aspect of the present invention, the elevation control means can determine the expected elevation position of the elevation body when the elevation drive means is operated by the set amount based on the information detected by the operation amount detection means. When the elevation position of the elevating body detected by the elevation position detecting means is different from the set position by more than a set value, the elevating / lowering conveyance of the article is abnormally stopped. That is, when there is a difference greater than the set value between the scheduled lifting position and the actual lifting position, it is determined that some abnormality has occurred in the operation amount detecting means or the lifting position detecting means, and safety is ensured. Can be planned.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of the present invention applied to a stacker crane in an article storage facility. Article storage facility S
As shown in FIG. 3, U is provided with a plurality of sets in which stacker cranes 2 are arranged between opposing storage shelves 1, each of which includes a self-propelled stacker crane 2 and a lifting mast of the stacker crane 2. The article transfer device LT provided on the elevator 4 is moved up and down by each of the article transfer units LT provided on the elevator 4 to move the articles A and the articles A to be moved in and out. Conveyor 6 for delivery of goods
Is placed at an appropriate position for the transfer of the articles, and the articles are transferred while being placed on the articles A, so that entry and exit from the storage shelf 1 are performed. Article storage facility SU
In addition, a shelf management device SC for performing an entry / exit command for the stacker crane 2 and management of stored articles A, etc.
And the shelf management device SC is connected to a higher-level management computer.

[0009] As shown schematically in FIG.
A plurality of elongate columns 7 erected in the vertical direction, article support beams 8 attached to the columns 7 at equal intervals in the vertical direction, and other shelf reinforcing members (not shown), An article A to be stored is supported by a pair of article support beams 8 between adjacent columns 7, and an article storage portion is formed on the pair of article support beams 8.

As described above, the stacker crane 2 is provided with a pair of front and rear elevating masts 3 in the moving direction thereof, and the traveling bogie unit 10 supporting the elevating masts 3 is guided by a traveling rail 11 on the ground side. At the same time, an upper beam 12 connecting the upper end of the lifting mast 3 is guided by a guide rail 13 on the ceiling side, and is movable in the lateral direction of the storage shelf 1. The traveling bogie unit 10 includes a traveling motor 14 (not shown in FIGS. 1 and 2) that rotationally drives a drive wheel 10 a of the traveling bogie unit 10, a lifting motor 15 that drives the lifting platform 4 to move up and down, and Is provided.

An elevating motor 15 is provided with a reduction drum 15 for winding and unwinding a pair of elevating wires 16 as a cord-like body for suspending and supporting the elevating table 4.
The lifting table 4 is moved up and down by being rotationally driven through a, and functions as a lifting drive means for driving the lifting wire 16 bidirectionally. The pair of lifting wires 16 that are farther from the position of the winding drum 17 include pulleys 21 and
2 and 23, the one on the near side is the pulley 22,
23 and is arranged so as to reach the winding drum 17. The rotating shaft of the winding drum 17 has
Although not shown in FIG. 2, a drive-side rotary functioning as an operation amount detection unit RS that detects the rotation amount of the winding drum 17 and detects the operation amount of the winding drum 17, that is, the feed driving amount of the lifting wire 16. An encoder 24 is provided. The output of the drive-side rotary encoder 24 is
As shown in (1), it is input to the crane control device CC for controlling the operation of the stacker crane 2.

As shown in FIG. 2, a slide fork type transfer device 5 (hereinafter simply referred to as "fork device 5") for supporting an article A in a mounted state is mounted on the lift 4 as an article transfer device LT, as shown in FIG.
(In the moving direction of the stacker crane 2), and the articles A can be transferred independently. The lift 4 is provided with a rotary encoder 18 for detecting the position of the lift 4, and a sprocket 1 attached to a rotating shaft of the rotary encoder 18.
9 meshes with a chain 20 fixed to one of the lifting masts 3, and a sprocket 19
Is rotated, and the elevator rotary encoder 18 outputs a pulse signal. The detection signal of the lift-table-side rotary encoder 18 is also input to the crane control device CC, similarly to the drive-side rotary encoder 24 described above.

Next, of the operation of the stacker crane 2 under the control of the crane control device CC, the elevation control of the elevator 4 will be described with reference to the flowchart shown in FIG. The crane control device CC controls the elevating motor 15 to control the elevating platform 4 at a predetermined elevating position, and the elevating control unit 30 functioning as the elevating control means UC.
A traveling control unit 31 that controls the operation of the traveling motor 14 to position the stacker crane 2 at a predetermined traveling position, and a transfer control unit 32 that controls the operation of the fork device 5. When the elevation control unit 30 receives, from the shelf management device SC, a transfer command of the article A that specifies the source article storage unit or the entry / exit conveyor 6 and the destination article storage unit or the entry / exit conveyor 6. Then, the transport command is decomposed into individual ascending or descending movements, and the ascending / descending control processing shown in the flowchart of FIG. 5 is executed.

The elevation control unit 30 adds the number of output pulses of the elevation rotary encoder 18 and the drive rotary encoder 24 with respect to the elevation origin position detected by detection means (not shown) when ascending, and adds the number of pulses when descending. Is always counted down so as to always specify the elevation position of the elevation table 4. The vertical origin position is set near the lower end of the vertical path of the vertical platform 4.

One of the two rotary encoders 18 and 24
Since the lift amount of the lift 4 per pulse does not usually match, the ratio of the number of output pulses of the rotary encoders 18 and 24 when the lift 4 is moved up and down by the same distance is obtained in advance and stored in the memory M. , The elevation control unit 30 includes a memory M
Is corrected based on the ratio of the number of output pulses stored in the rotary encoders 18 and 24. Hereinafter, the elevator-side rotary encoder 18 and the drive-side rotary encoder 24 after this correction are performed.
Are represented as “A” and “B”, respectively. Therefore, the contents of the data “A” and “B” are constantly rewritten as the elevator 4 moves up and down. By this correction, the count value after the correction is obtained by using the rotary encoder 18 on the lift platform side and the rotary encoder 2 on the drive side.
Basically, the count values after the correction are specified as the ascending and descending positions.
Therefore, the lift-table rotary encoder 18 and the lift control unit 30 function as the lift position detecting means PS for directly detecting the lift body 4 and detecting its lift position.

The elevation control unit 30 controls the elevation motor 15 in a normal elevation mode in which the elevation motor 15 is controlled by the elevation position specified based on the detection information of the driving rotary encoder 24 in principle. In this normal lifting mode,
The control of the elevating speed of the elevating table 4 is also performed based on the detection information of the drive-side rotary encoder 24. More specifically, the ascending / descending control is performed by “B + C” obtained by adding a correction count value “C” for correcting the extension / contraction of the elevating wire 16 due to the loading / unloading of the article A to the count value “B”.
The correction count value “C” is rewritten each time an article is loaded or unloaded, but may be rewritten every time the lifting table 4 is moved up or down. In the initial state where the article A is not mounted on the lift 4, “C” is “0”.

Upon receiving the transport command from the shelf management device SC, the lifting control unit 30 raises and lowers the lifting table 4 by the processing in the flowchart of FIG. That is, first, the "stop position" and the "deceleration start position" of the destination are set, and the ascent / descent is started (step # 1). Here, "stop position"
Means that the article transfer device LT is a slide fork type transfer device 5
Therefore, if the movement at that time is a “rake operation” in which the article A in the article storage section is transferred to the elevator 4 side, the article placement surface of the fork device 5 is If the position is set slightly lower than the article placement surface, and if the article A mounted on the elevator 4 is transferred to the article storage unit, the article placement surface of the fork device 5 is set to the article placement position. A position slightly higher than the article placement surface of the storage section is set.
The “deceleration start position” is set before the “stop position” by a set distance.
Is started so that the slowing speed becomes slightly before the "stop position".

After the elevating table 4 starts ascending and descending, the count value “B +
C "reaches the" deceleration start position "(step # 2).
Decelerate to a predetermined creep speed (step # 3),
When the “stop position” is reached, the elevator 4 is stopped (steps # 4 and # 5), and an elevation completion signal is transmitted to the transfer controller 32. After the stop, it is determined whether or not the above-mentioned “stop position”, that is, the planned elevating position, and the elevating position (count value “A”) specified by the detection information of the elevating table side rotary encoder 18, that is, the actual elevating position, are equal to or more than a set value (Step # 6), if the difference is outside the allowable range by more than the setting, the operation based on the transfer command from the shelf management device SC is terminated and abnormally stopped (Step # 13). Then, a return processing request is transmitted (step # 14). Upon receiving this return processing request, the shelf management device SC displays on the monitor of the shelf management device SC that the operator should investigate the cause of the abnormality and perform recovery work.

In step # 6, if the scheduled lifting position does not differ from the actual lifting position by more than the set value, a protrusion completion signal indicating that the fork device 5 has completed the protrusion operation is received from the transfer control unit 32. (Step # 7). In parallel with the elevating movement under the control of the elevating control unit 30 described above, the movement of the stacker crane 2 is controlled by the control of the running control unit 31 to the running position corresponding to the article storage unit to be transferred. The transfer control unit 32 receives the lifting completion signal from the lifting control unit 30 and receives the traveling completion signal from the traveling control unit 31, and causes the fork device 5 to protrude toward the article storage unit. Control unit 3
Send a projecting completion signal to 0.

Upon receiving the protrusion completion signal (step # 7), the lifting controller 30 sets the article mounting surface of the fork device 5 to the article support beam if it is a "rake operation" at this point (step # 8). The lifting platform 4 is raised so as to be located at a position slightly higher than the article mounting surface 8 (Step # 9),
When the ascent is completed, the completion of the ascent is transmitted to the transfer control unit 32. The ascending movement at this time is executed by switching from the normal elevating mode to the transfer elevating mode in which the elevating motor 15 is controlled based on the elevating position specified by the detection information of the elevating table side rotary encoder 18.

By the ascending movement of the "rake operation", the article A is placed on the article placing surface of the fork device 5, the load is applied to the lift 4 and the lift wire 16 is extended. Therefore,
Due to the extension of the lifting wire 16, a difference is generated between the lifting position specified based on the detection information of the lifting rotary encoder 18 and the lifting position specified based on the detection information of the driving rotary encoder 24. Specifically, at the time of this “rake operation”, the drive-side rotary encoder 2
The lift position specified based on the detection information of No. 4 is higher than the lift position specified based on the detection information of the lift base rotary encoder 18.

Therefore, the elevation control unit 30 determines the elevation position (count value “A”) identified based on the detection information of the elevation rotary encoder 18 at this time based on the detection information of the driving rotary encoder 24. Then, the ascending / descending position (count value "B") is subtracted, and the ascending / descending position is corrected by rewriting the corrected count value "C" with the result of the subtraction (step # 11). That is, based on the detection information of the elevation position detection means PS, the detection information of the operation amount detection means RS is corrected by the amount of change in the elevation position when the fork device 5 performs the loading / unloading operation of the article A, and the motor for elevation is corrected. 15 is controlled.

On the other hand, at the time of the "lowering operation" (step # 8), the lifting platform 4 is moved so that the article mounting surface of the fork device 5 is located slightly lower than the article mounting surface of the article support beam 8.
Is lowered (step # 10). When the lowering is completed, the completion of the lowering is transmitted to the transfer controller 32. The descending movement at this time is also executed by switching from the normal elevating mode to the transfer elevating mode in which the elevating motor 15 is controlled based on the elevating position specified by the detection information of the elevating table side rotary encoder 18. That is, the lifting control unit 30 functioning as the lifting control unit UC controls the lifting motor 15 based on the detection information of the operation amount detection unit RS in a state where the fork device 5 is in the protruding operation for loading and unloading the articles A. From the normal elevating mode controlled by the elevating motor 15 based on the detection information of the elevating position detecting means PS.
Is switched to the transfer / elevating mode for controlling the lifting and lowering of the lifting platform 4.

In the case of the "unloading operation", the article A placed on the article mounting surface of the fork device 5 is transferred to the article support beam 8, contrary to the above-mentioned "rake operation". The lifting wire 16 shrinks. Then, similarly to the above-mentioned “rake operation”, the elevation control unit 30 determines the elevation position (count value “A”) specified based on the detection information of the elevation table-side rotary encoder 18 at this time, and sets the drive-side rotary encoder 2
The vertical position (count value "B") specified based on the detection information of No. 4 is subtracted, and the vertical position is corrected by rewriting the correction count value "C" with the result of the subtraction (step # 11).

The transfer control unit 32 performs the above-described “rake operation”.
When the fork device 5 receives the completion signal of the ascending movement in the above or the completion signal of the descending movement in the "lowering operation", the fork device 5 is operated to retreat. Lift control unit 3
In the case of No. 0, the process of FIG. 5 is terminated in response to receiving the retirement operation completion signal from the transfer control unit 32 (step # 12), and the process of FIG. In other words, the process of FIG. 5 is executed twice for transporting one article A.

[Other Embodiments] Other embodiments of the present invention will be listed below. In the above embodiment, the elevation position detection means PS is configured by the elevation table-side rotary encoder 18 and the elevation control unit 30 that counts output pulses of the encoder.
For example, the traveling bogie unit 10 is provided with a distance measuring means for measuring the distance to the lift 4 and the detection information of the distance measuring means is specified as the lift position of the lift 4. Can be changed. In the above embodiment, the slide fork type transfer device 5 is illustrated as the article transfer device LT.
May be configured as a so-called hook-type transfer device provided with a hook that is capable of locking a part of the product storage portion so as to be able to move back and forth from the lifting platform 4 to the article storage section. In the above-described embodiment, the lifting wire 16 is illustrated as a cord-like body that suspends and supports the lifting platform 4, but the specific configuration thereof can be variously changed, for example, by using a chain or the like.

In the above embodiment, the elevation control unit 30
Is controlled by “B + C” obtained by adding the correction count value “C” to the count value “B” based on the output pulse of the drive-side rotary encoder 24, and when the article A is transferred by the fork device 5, The up / down position (count value “B”) specified based on the detection information of the drive side rotary encoder 24 is subtracted from the up / down position (count value “A”) specified based on the detection information of the encoder 18, and the corrected count value is calculated. The vertical position is corrected by rewriting “C” with the result of the subtraction,
Instead of using the corrected count value “C”, the ascending and descending control is performed using the count value “B”, and the count value “B” is replaced with the count value “A” when the article A is transferred by the fork device 5. By correcting the elevating position, the detection information of the operation amount detecting means RS is corrected by the amount of change of the elevating position when the fork device 5 performs the unloading operation of the article A based on the detection information of the elevating position detecting means PS. Thus, the lifting motor 15 may be configured to be controlled. In the above embodiment, the case where the lifting and lowering transport device of the present invention is applied to the stacker crane 2 is illustrated, but the present invention can be applied to various lifting and lowering transport devices such as an elevator.

[Brief description of the drawings]

FIG. 1 is a front view of a stacker crane according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of the stacker crane according to the embodiment of the present invention.

FIG. 3 is an external perspective view of the article storage facility according to the embodiment of the present invention.

FIG. 4 is a block diagram according to an embodiment of the present invention.

FIG. 5 is a flowchart according to the embodiment of the present invention.

[Explanation of symbols]

 LT article transfer device PS lifting / lowering position detection means RS operation amount detection means UC lifting / lowering control means 4 lifting / lowering body 5 slide fork type transfer apparatus 15 lifting / lowering driving means 16 cord-like body

Claims (3)

[Claims] 1. An article transfer device, comprising: an elevating body capable of loading and unloading articles; elevating drive means for feeding and driving a rope supporting the elevating body, and the cable by the elevating drive means. An ascending / descending transport device provided with an actuating amount detecting means for detecting a feed driving amount of the body, and ascending / descending control means for controlling the ascending / descending driving means based on detection information of the actuating amount detecting means, Lifting / lowering position detecting means for detecting a lifting / lowering position of the lifting / lowering body is provided; and the lifting / lowering control means is configured to lift and lower when the article transfer device performs an operation of loading / unloading articles based on the detection information of the lifting / lowering position detecting means. An ascending and descending transport device configured to control the ascending and descending drive means by correcting detection information of the operation amount detecting means based on a change amount of a position. 2. The apparatus according to claim 2, wherein the article transfer device is a slide fork type transfer device, and the lifting / lowering control means is configured to operate the slide fork type transfer device in a projecting operation for loading and unloading articles. Switching from a normal elevating mode in which the elevating drive means is controlled based on the detection information of the operation amount detecting means to a transfer elevating mode in which the elevating drive means is controlled based on detection information of the elevating position detecting means. The elevating and conveying device according to claim 1, wherein the elevating body is configured to elevate and lower. 3. The elevation control means detects a scheduled elevation position of the elevating body when the elevation drive means is operated by a set amount based on the detection information of the operation amount detection means, and detects the elevation position by the elevation position detection means. The elevating / lowering apparatus according to claim 1 or 2, wherein the elevating / lowering apparatus is configured to abnormally stop the elevating / lowering / conveying of the article when the elevating / lowering position of the elevating / lowering body is different from the set position by more than a set value.