JPH04298497A - Crane accident preventive device in automated high raised warehouse - Google Patents

Abstract

PURPOSE:To prevent occurrence of an accident of a stacker crane in an automated warehouse beforehand. CONSTITUTION:A judgment is made on whether or not weight of a work 40 is excessive to a stacker crane 6 by converting electric power of a transport motor 19 of a work transport machine 18 measured by means of a current transformer 19a into weight of the work 40. A judgment is made on whether or not abnormality is caused in the stacker crane 6 by comparing electric power of a raising/lowering motor 12 of the stacker crane 6 measured by means of a current transformer 12a with already-known actual weight of the work 40. A judgment is made on elongation of a raising/lowering chain 13 from a position of a carriage 10 detected by means of an origin sensor 16 and a position of the raising/lowering chain 13 measured by means of a raising/lowering encoder 15.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is used in multi-level automated warehouses such as FMS, to prevent overweight cargo being loaded onto a crane.
This invention relates to a crane accident prevention device that automatically determines abnormalities such as oil shortage in the lifting section (loading section and its lifting/lowering drive means) of the crane, and the extension of the chain of the lifting section of the crane during operation.

0002

[Prior Art] Conventionally, accident prevention measures for cranes, etc. in multi-level automated warehouses have been carried out automatically, such as emergency stops when chains are cut, and detection of the width of loaded cargo (workpieces, etc.). Mainly, maintenance and inspection at predetermined intervals are performed by workers. In other words, in order to prevent accidents due to overloading, it is necessary for workers to measure the weight of the cargo to be loaded onto the crane of the multi-story automated warehouse in advance using a scale installed outside the multi-story automated warehouse. be. Furthermore, in order to prevent accidents due to malfunctions of the crane itself, it is necessary for the operator to perform maintenance checks such as oil replacement of the crane at each predetermined maintenance check period.

0003

[Problems to be Solved by the Invention] However, accident prevention measures that rely too much on the voluntary management of workers have a high risk of leading to serious accidents due to worker negligence. In other words, there was no weighing scale capable of measuring large weights,
Or, because the worker simply forgets, an overweight load may be loaded onto the crane without being weighed, resulting in a serious accident. Additionally, maintenance inspections must be carried out after the operation of the multi-story automated warehouse has been stopped, but since many automated multi-story warehouses operate 24 hours a day, it is not possible to allocate time for maintenance and inspection, which may result in delays in maintenance and inspection. ,
Furthermore, the maintenance and inspection period may be delayed because the operator forgets to do so. Although it is practically possible to continue operating a multi-story automated warehouse without maintenance and inspection, ignoring the occurrence of abnormalities may lead to serious accidents.

[0004] In view of the above circumstances, the present invention has been made to reduce the weight of luggage,
An accident prevention device for cranes in multi-storey automated warehouses that can automatically determine abnormalities in equipment while the automated multi-storey warehouse is in operation and prevent accidents by assisting workers in maintenance and inspection. The purpose is to provide

[0005]

[Means for Solving the Problems] The present invention provides luggage (40)
It has a loading section (10, 11) for loading the loading section (
In a multi-level automated warehouse (3) equipped with a crane (6) that takes cargo (40) in and out of shelves (5a) by moving it up and down, cargo (40) is placed horizontally. A cargo transfer means (18) is provided for transferring the cargo from the cargo loading position (17a) to the cargo delivery position (17b) to the crane (6) by moving the cargo in the direction.
A motor (19) for driving the load (40) is provided, and while the load (40) is being transferred by the load transfer means (18), the amount of electric power equivalent to the motor (19) is measured to drive the load (40) being transferred. ) is provided, and a weight corresponding value determining means (19a, 24, 33) is provided for determining a weight corresponding value corresponding to the weight of A value storage means (34) is provided, and the weight corresponding value determined by the weight corresponding value determining means (19a, 24, 33) and the upper limit value storing means (34) are provided.
) is provided to determine whether the weight of the load (40) being transferred is not excessive for the crane (6), The overweight determining means (25) determines whether the cargo being transported (
If it is determined that the weight of the crane (40) is excessive for the crane (6), an overweight warning means (31,
31a).

[0006] Furthermore, the present invention provides a storage space for storing luggage (40) on a shelf (5a).
), the crane (6) is provided with a loading section (10, 11) for loading cargo (40) so as to be movable up and down; A motor (12) that drives the loading section (10) up and down.
) is provided, and a power equivalent amount measuring means (12a) is provided for measuring the amount of electric power equivalent to the motor (12) while the load (40) is being lifted and lowered by the crane (6), and the load (40) is being lifted and lowered by the crane (6). A weight corresponding value storage means (36) storing a weight corresponding value corresponding to the weight of the motor (12) is provided, and the electric power equivalent amount of the motor (12) measured by the electric power equivalent amount measuring means (12a) is stored in the weight corresponding value. abnormal load determination means (27, 28,
35), and the abnormal load determination means (27, 28, 3
5), when it is determined that the amount of electric power equivalent to the motor (12) is excessive with respect to the value corresponding to the weight of the cargo (40) being lifted and lowered, an abnormality occurrence warning means (3) issues a warning.
1, 31a).

[0007]Further, the present invention provides a method for storing luggage (40) on a shelf (5a).
), the crane (6) is provided with a loading section (10, 11) for loading cargo (40) so as to be movable up and down; A motor (12) that drives the loading section (10) up and down.
) is connected to the loading section (10) via a chain (13), and a chain position measuring means (15) for measuring the position of the chain (13) is provided, and the loading section (1
position detecting means (16) for detecting the position of the chain (13) and the position of the chain (13) measured by the chain position measuring means (15) and the loading section detected by the position detecting means (16). Extension calculation means (10) for calculating the extension of the chain (13) based on the position of
29), and regarding the extension length of the chain (13),
A limit judgment value storage means (37) storing a limit judgment value is provided, and the extension of the chain (13) calculated by the extension calculation means (29) and the limit judgment value storage means (37) are provided.
The chain (
13) is provided, and when the chain replacement determining means (30) determines that the chain (13) needs to be replaced, the chain replacement system issues a warning. Warning means (31, 31
a).

[0008] The numbers in parentheses are for convenience and indicate corresponding elements in the drawings.
This description is not limited to the description on the drawings. The same applies to the "effect" column below.

[0009]

[Operation] With the above-described configuration, when a load (40) that is too heavy for the crane (6) is carried into the load transfer means (18), when transferring the load (40), the load transfer means ( 18) so that the electric power equivalent amount of the motor (19) that drives the motor (18) becomes large.

[0010] Furthermore, if some abnormality occurs in the crane (6), the loading section (
10) so that the electric power equivalent amount of the motor (12) that drives the motor (10) becomes large.

Furthermore, when the chain (13) stretches, the position of the chain (13) shifts relative to the position of the loading section (10).

0012

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings. FIG. 1 is a perspective view showing a stacker crane and loading station of an automated warehouse to which the accident prevention device according to the present invention is applied, FIG. 2 is a control block diagram of the automated warehouse shown in FIG. 1, and FIG. A diagram showing the relationship between power and load factor, FIG. 4 is a flowchart showing a work weight check program, FIG. 5 is a schematic diagram showing a method for measuring chain extension, and FIG. 6 is a flowchart showing a crane check program. 7 is a perspective view of machine tool equipment equipped with the automatic warehouse shown in FIG. 1.

The machine tool equipment 1 shown in FIG. 7 is provided with a plurality of machine tools 2, and is further provided with an automatic warehouse 3 to which the accident prevention device according to the present invention is applied. The automated warehouse 3 has a stocker 5, and the stocker 5 includes:
A large number of workpiece mounting shelves 5a are provided and arranged three-dimensionally (in the vertical and horizontal directions). A stacker crane 6 is movably provided in the automated warehouse 3 so as to communicate between the machine tool 2 and each workpiece mounting shelf 5a of the stocker 5.

As shown in FIG. 1, the stacker crane 6 has a running section 7 that runs on a rail 6a and is arranged in the direction of arrow A.
, are provided so as to be freely movable and driveable in the B direction (horizontal direction). Columns 9, 9 are installed upright in the running section 7, and a carriage 10 is mounted between the columns 9, 9 in the directions of arrows C and D (
It is installed so that it can be freely driven up and down in the vertical direction. and,
A fork 11 is provided on the carriage 10 so as to be freely protrusive and retractable in the directions of arrows E and F (horizontal direction). That is, sprockets 14a and 14b are rotatably provided at the upper and lower parts of each column 9 in the figure, respectively.
A lifting chain 13 is attached to the sprockets 14a and 14b so as to be able to rotate freely along the column 9. The ends 13a and 13b of the lifting chain 13 are each
The lifting chain 13 is connected to the upper and lower parts of the carriage 10 in the figure, and the ends 13a and 13b of the lifting chain 13 are connected to the carriage 1.
0, thereby forming an annular (endless) shape. A lifting motor 12 is connected to the sprocket 14b, and by rotationally driving the sprocket 14b via the lifting motor 12, the lifting chain 13 rotates between the sprockets 14a and 14b, and the carriage 10 moves up and down in the directions of arrows C and D. A current transformer 12a is connected to the lifting motor 12, and a lifting encoder 15 is connected to the sprocket 14a. In addition, in carriage 10,
An origin sensor 16 is fixed to the column 9, and a dog 16a corresponding to the origin sensor 16 is fixed to the column 9. Further, the automatic warehouse 3 is provided with a loading station 17. loading station 17
, the work transfer device 18 is configured to transfer the work 40 in the directions of arrows G and H (horizontal direction) between the work setup position 17a and the work transfer position 17b via the transfer motor 19. It is provided. A current transformer 19a is connected to the transfer motor 19.

The automated warehouse 3 includes a control device 20 shown in FIG.
is provided. The control device 20 has a main control section 21, and the main control section 21 is connected to the main control section 21 via a bus line 21a.
Input/output control section 22, loading station control section 2
3. Work weight conversion unit 24, over weight determination unit 25, crane control unit 26, work weight conversion unit 27, crane abnormality determination unit 28, chain extension calculation unit 29, chain extension determination unit 30, warning device control unit 31, A crane management data memory 32, a workpiece weight conversion parameter memory 33, an upper limit parameter memory 34, a workpiece weight conversion parameter memory 35, a workpiece weight approximate value memory 36, a chain management data memory 37, a system program memory 38, and the like are connected. The input/output control section 22 includes:
Input/output device 22a such as CRT display and keyboard
is connected. A transfer motor 19 is connected to the loading station control section 23, and a current transformer 19a is connected to the workpiece weight conversion section 24. The crane control unit 26 includes a lifting motor 12.
, a lifting encoder 15, an origin sensor 16, etc. are connected to the workpiece weight conversion section 27, and a current transformer 12a
is connected. The chain extension calculation section 29 includes:
The elevation encoder 15 is connected. The warning device control unit 31 also includes a warning device 3 such as a warning lamp.
1a is connected.

Since the machine tool equipment 1 and the automatic warehouse 3 have the above-described configuration, a predetermined workpiece 40 is transferred to the machine tool 2.
In order to process the workpiece 40, prior to processing, the operator sets up the workpiece 40 on a pallet at the workpiece setup position 17a of the loading station 17 shown in FIG. Input is made from the keyboard of the device 22a. When the preparation of the workpiece 40 is completed, the main control unit 21 of the control device 20 reads the workpiece weight check program WCP shown in FIG. 4 from the system program memory 38, and performs the following operations based on the workpiece weight check program WCP. Then, while determining whether the weight of the workpiece 40 is excessive for the stacker crane 6, the workpiece transfer machine 18 is driven via the loading station control unit 23 to move the workpiece 40 from the workpiece setup position 17a. It is transferred to the delivery position 17b. First, in step W1 in FIG. 4, the main controller 21 controls the loading station controller 2.
3, the transfer motor 19 is started to be driven, and the workpiece 40 placed on the workpiece transfer device 18 is moved in the direction indicated by the arrow G in FIG.
move in the direction. When the workpiece transfer machine 18 starts operating, when the speed of the workpiece 40 moving on the workpiece transfer machine 18 becomes constant (when the workpiece 40 is running at steady speed, not during acceleration or deceleration), step W2 is entered, and the workpiece 40 is transferred. The electric power of the motor 19 is measured by a current transformer 19a. In addition, when the transfer motor 19 is under inverter control, a current transformer for inverter control can be used as the current transformer 19a. (The same applies to the current transformer 12a of the lifting motor 12, which will be described later.) Next, in step W3, the main control unit 21 converts the transfer weight measured by the current transformer 19a through the workpiece weight conversion unit 24. motor 19
The power value of the workpiece 40 being transferred on the workpiece transfer machine 18 is
An approximate workpiece weight WT for the workpiece 40 is calculated by converting it into the weight of the workpiece 40. That is, the workpiece weight conversion parameter memory 33 includes the transport motor 19 as shown in FIG.
A work weight conversion parameter WP1 indicating the correlation between power and load factor is stored in advance. Then, the workpiece weight conversion unit 24 converts the workpiece weight conversion parameter WP1
Based on this, the load factor of the transfer motor 19 corresponding to the power value measured by the current transformer 19a is determined, and the obtained load factor is further converted into an approximate workpiece weight value WT. That is, when the workpiece 40 is transferred by the workpiece transfer machine 18, the larger the weight of the workpiece 40 is, the more the transfer motor 1 is moved.
9 becomes larger, and therefore the electric power of the transfer motor 19 becomes larger. Therefore, by measuring the electric power of the transfer motor 19, the weight of the workpiece 40 being transferred on the workpiece transfer machine 18 (approximate workpiece weight value) WT) can be calculated. Note that the weight of the workpiece 40 on the workpiece transfer machine 18 may be calculated by measuring the current instead of measuring the electric power of the transfer motor 19, but as shown in FIG. Since the correlation between power and load factor is closer to linear than the correlation between power and load factor, measuring the power of the transfer motor 19 as described above will more accurately determine the weight of the workpiece 40 being transferred (approximate workpiece weight WT). can be calculated. When the approximate workpiece weight WT for the workpiece 40 being transferred on the workpiece transfer machine 18 is calculated, step W4 in FIG.
, the main control unit 21 determines the weight of the workpiece 40 (approximate workpiece weight value WT) via the overweight determination unit 25.
It is determined whether the amount is too large for the stacker crane 6. That is, the maximum load weight of the stacker crane 6 is stored in the upper limit parameter memory 34 in advance as the upper limit parameter LP. Then, the overweight determination unit 25
The approximate workpiece weight WT for the workpiece 40 calculated by the workpiece weight conversion unit 24 is compared with the upper limit parameter LP in the upper limit parameter memory 34, and the weight of the workpiece 40 being transferred on the workpiece transfer machine 18 (approximate workpiece weight) is calculated. It is determined whether the value WT) is excessive for the stacker crane 6. In addition, the maximum loading weight of the stacker crane 6 is converted into the electric power value (or current value) or load factor of the transfer motor 19 when the workpiece 40 of the weight is transferred by the workpiece transfer device 18, and the maximum weight in terms of electric power value is calculated. The weight (or the maximum weight converted into current value) or the maximum weight converted into load factor is determined in advance and stored in the memory means, and the current power value of the transfer motor 19 measured by the current transformer 19a during the transfer of the workpiece 40 is calculated. (or current value) directly or by converting it into a load factor (without converting to the approximate workpiece weight WT),
It may be determined whether the weight of the workpiece 40 being transferred is excessive for the stacker crane 6 by comparing it with the maximum weight converted into electric power value (or the maximum weight converted into current value) or the maximum weight converted into load factor. good.

If it is determined that the weight of the workpiece 40 being transferred is too large for the stacker crane 6, step W is performed.
Step W5 is entered from step W5, and the main control section 21 controls the work transfer machine 1 via the loading station control section 23.
At the same time, in step W6, the warning device 31a issues a warning to the operator via the warning device control unit 31. That is, even if the operator has not measured the weight of the workpiece 40 at the loading station 17 in advance, if the weight of the workpiece 40 is too large for the stacker crane 6, the workpiece transfer machine 18 will not be able to move the workpiece 40. Transfer to the stacker crane 6 is not performed. Therefore, overweight work 40 is prevented from being loaded onto stacker crane 6, and when stacker crane 6 receives work 40 or when lifting/lowering work 40 by stacker crane 6, fork 11 and carriage 10 are It is possible to prevent serious accidents such as damage from occurring.

When it is determined that the weight of the workpiece 40 being transferred is not excessive for the stacker crane 6, step W is performed.
4, the main control unit 21 proceeds to step W6, and the main control unit 21 continues the transfer of the workpiece 40 by the workpiece transfer device 18. and,
In step W7, with respect to the same work number as the work number of the work 40 for which the workpiece weight approximate value WT was calculated by the workpiece weight converter 24 this time, the workpiece weight approximate value WT was previously calculated by the workpiece weight converter 24. If so, step W8 is entered, and the main control unit 21
For the same workpiece number, the previously calculated estimated workpiece weight WT is read out from the estimated workpiece weight memory 36 and compared with the currently calculated weight conversion value WT. In step W9, if there is a difference greater than the error, step W10 is entered, and a "confirmation message" for the operator is displayed on the CRT display or the like of the input/output device 22a via the input/output control unit 22. Then, when the operator's confirmation is obtained, the process proceeds from step W10 to step W11. In addition, in step W7 described above, regarding the work number that is the same as the work number of the work 40 for which the work weight approximate value WT has been calculated by the work weight conversion unit 24 this time, it is assumed that the work weight approximate value WT has been calculated previously. If not, the process goes to step W11. Further, in step W9 described above, if the difference between the previously calculated workpiece weight approximate value WT and the currently calculated workpiece weight conversion value WT for the same workpiece number is within the error range, step W11 is entered. Then, in step W11, the main control unit 21 stores the currently calculated estimated work weight WT regarding the work 40 with the predetermined work number in the estimated work weight memory 36 in a readable form based on the work number. (The previously calculated estimated workpiece weight WT for the same workpiece number is deleted). Note that the estimated workpiece weight WT in the estimated workpiece weight value memory 36 is used as the actual weight of the workpiece 40 in abnormality checking of the stacker crane 6, as described later. Since the workpiece weight estimate WT calculated last time and the workpiece weight estimate WT calculated this time regarding the workpiece number are compared and checked, the reliability of the workpiece weight estimate WT in the workpiece weight estimate memory 36 is improved. Then, in step W12, when the operation of the workpiece transfer machine 18 is finished, the main control unit 21 starts the workpiece weight check program WCP.
end.

The workpiece 40 set up at the loading station 17 is transferred to the workpiece delivery position 17 shown in FIG.
6, the main control unit 21 reads the crane check program CCP shown in FIG. The stacker crane 6 is driven via the crane control unit 26 while determining whether the chain 13 is elongated or there is any other abnormality, and the work 40 is moved from the loading station 17 to a predetermined position of the stocker 5 shown in FIG. The workpieces are transported and stored in the workpiece storage shelf 5a. First, in step S1 in FIG. 6, if the current operation of the stacker crane 6 is the first operation after replacing the lifting chain 13, the process proceeds to step S2, and the main control unit 21 controls the operation via the crane control unit 26. Then, the carriage 10 of the stacker crane 6 is moved to the machine home position. That is, the crane control unit 26 drives the lifting motor 12 to lower the carriage 10 in the direction of arrow D in FIG. Then, the origin sensor 16 comes into contact with the dog 16a, and the origin sensor 1
When a predetermined signal is input from 6, the crane control unit 26
stops the lifting motor 12 and stops the carriage 10. Then, in step S3 in FIG. 6, the main control unit 21 reads the initial origin position data A from the lifting encoder 15 via the chain extension calculation unit 29, and converts the initial origin position data A into the chain management data. It is stored in the memory 37. When the initial origin position data A is thus stored, the process proceeds to step S4. Furthermore, in step S1 described above, the current operation of the stacker crane 6 is the second or subsequent operation after replacing the lifting chain 13, and the initial origin position data A has already been stored in the chain management data memory 37. If so, step S
Enter 4. Then, in step S4, the current operation of the stacker crane 6 is the Nth operation after the lifting chain 13 was replaced (N can be set or changed as a parameter), and the lifting chain 13 is replaced. If the time is approaching, the process proceeds to step S5. The main controller 21 then drives the lifting motor 12 via the crane controller 26 to move the carriage 10 of the stacker crane 6 to the machine origin position where the origin sensor 16 comes into contact with the dog 16a. Then, the main control unit 21 calculates the extension amount X of the lifting chain 13 via the chain extension calculation unit 29. That is, in step S6, the chain extension calculation unit 29
Read the current origin position data B from the step S7.
In this step, the initial origin position data A is read from the chain management data memory 37, and the current origin position data B is read out from the chain management data memory 37.
and the initial origin position data A to calculate the extension amount X of the lifting chain 13. That is, as shown in FIG. 5, when the lifting chain 13 is extended by the extension amount X, the part of the lifting chain 13 that was at position P1 when returning to the machine home in the first operation will become the machine home in the Nth and subsequent operations. Since it has moved to position PN at the time of return, the extension of the lifting chain 13 can be determined by finding the distance between position P1 and position PN as the difference between the initial origin position data A and the current origin position data B of the elevator encoder 15. Quantity X can be calculated.

When the elongation X of the elevating chain 13 is calculated, in step S8 of FIG. 6, the main control section 21 determines via the chain elongation determining section 30 whether or not the elevating chain 13 needs to be replaced. That is, the chain elongation determination section 30
The length L of the lifting chain 13 is read from the chain management data memory 37. Then, the chain extension determining unit 30 compares the extension amount X of the lifting chain 30 calculated by the chain extension calculation unit 30 with the length L of the lifting chain 30 read from the chain management data memory 37.
The degree of elongation of the lifting chain 13 is classified into three levels: "Level 1", "Level 2", and "Level 3". In other words, if the extension X is less than 1% of the length L (0≦X<L/100), it is determined to be "level 1", and the extension X is 1% or more and less than 1.5% of the length L. If (L/100≦X<15L/1000), it is determined to be "level 2", and the extension amount X is 1.
If it is 5% or more (15L/1000≦X), it is determined to be “level 3”. If the elongation of the lifting chain 13 is at "level 3", which is the dangerous level, the process proceeds from step S9 to step S10, and the main control unit 21, via the warning device control unit 31, turns on the red warning of the warning device 31a. At the same time as turning on the lamp, the operation of the stacker crane 6 is stopped via the crane control unit 26 in step S11. Then, in step S12, the main control unit 21
is the C of the input/output device 22a via the input/output control unit 22.
A “chain replacement instruction message” is displayed for the operator on the RT display, etc. In other words, even if the operator does not properly replace the lifting chain 13, such as by continuing to use the lifting chain 13 whose replacement period has passed, if the extension length X of the lifting chain 13 becomes 1.5% or more, , the operation of the stacker crane 6 is stopped. Therefore, it is possible to prevent the lifting chain 13 from breaking, and therefore, it is possible to prevent serious accidents from occurring when the workpiece 40 is lifted and lowered by the stacker crane 6. Then, when the lifting chain 13 is replaced by the worker, the process proceeds from step S13 to step S14, and the main control section 21 receives input from the keyboard or the like of the input/output device 22a by the worker via the input/output control section 22. Based on the data stored in the chain management data memory 37
Update various data such as chain replacement timing data. In addition, when the degree of elongation of the lifting chain 13 is "level 2" which is the caution level, the process proceeds from step S9 described above to step S15, and the main control section 21 controls the warning device via the warning device control section 31. After lighting the yellow warning lamp 31a, the process proceeds to step S17. Therefore, it is possible to call the operator's attention to the timing of replacing the lifting chain 13. Further, if the extent of elongation of the lifting chain 13 is "level 1" which is the safety level, the process proceeds from step S9 described above to step S16, and the main control section 21 controls the warning device via the warning device control section 31. After lighting the blue warning lamp 31a, the process proceeds to step S17. Then, the main control unit 21, via the crane control unit 26, corrects the extension of the position data of the lifting encoder 15 based on the extension amount X of the chain 13 calculated by the chain extension calculation unit 29 in step S17. After performing this, the operation of the stacker crane 6 is started in step S18.

Further, in step S4 described above, if the current operation of the stacker crane 6 is the (N-1)th operation or earlier after the lifting chain 13 has been replaced, the process proceeds to step S18, and the stacker crane 6 starts operation. That is, when entering step S18, the main control unit 2
1 drives the running section 7 of the stacker crane 6 to move in the directions of arrows A and B in FIG. 1 as appropriate via the crane control section 26,
The carriage 10 is appropriately driven up and down in the directions of arrows C and D, and the fork 11 is appropriately driven to protrude and retreat in the directions of arrows E and F.
The prepared workpiece 40 is loaded onto the carriage 10, and transported from the loading station 17 to the workpiece storage shelf 5a at a predetermined position of the stocker 5 shown in FIG. 7 and stored therein. When moving the carriage 10 up and down in the directions of arrows C and D in FIG.
While determining the position of the carriage 10, the lifting motor 12 is driven. When the carriage 10 loaded with the workpiece 40 is moved up and down, when the speed of the carriage 10 becomes constant (not during acceleration or deceleration, but when the carriage is running at a steady state), the process enters step S19 in FIG. 12 is measured by current transformer 12a. Note that, in the same manner as in the case of obtaining the approximate workpiece weight WT of the workpiece 40 being transferred at the loading station 17 described above, the current may be measured instead of measuring the electric power of the lifting motor 12. Next, step S
20, the main control unit 21 includes a workpiece weight conversion unit 27
The power value of the lifting motor 12 measured by the current transformer 12a is determined by the workpiece 40 being lifted and lowered on the carriage 10 when the stacker crane 6 is considered to be normal.
The workpiece weight conversion load factor WT' of the lifting motor 12 during driving (substantially, the workpiece weight approximate value WT calculated by the aforementioned workpiece weight conversion section 24)
It is similar to ) is calculated. That is, the workpiece weight conversion parameter memory 35 stores in advance a workpiece weight conversion parameter WP2 indicating the correlation between the electric power and the load factor regarding the lifting motor 12 as shown in FIG. Then, the workpiece weight conversion unit 27 converts the workpiece weight conversion parameter WP2 in the workpiece weight conversion parameter memory 35 to
Based on this, the load factor of the lifting motor 12 corresponding to the power value measured by the current transformer 12a is determined, and the obtained load factor is further converted into a work weight conversion load factor WT'. That is, when a work of a predetermined weight is loaded on the carriage 10 of the stacker crane 6 in a normal state and the workpiece is lifted and lowered, the electric power value (or converted load factor) of the lifting motor 12 measured by the current transformer 12a is , is the same as the current electric power value (or converted load factor) of the lifting motor 12 measured by the current transformer 12a in step S19 of FIG. 6, the electric power value of the lifting motor 12 calculated in step S20 The workpiece weight conversion load factor WT' matches the weight of the workpiece. When the workpiece weight conversion load factor WT' of the lifting motor 12 that is being driven is calculated, step S2
1, the main control unit 21 controls the crane abnormality determination unit 28.
The load on the lifting motor 12 while it is being driven (workpiece weight conversion load ratio WT') is calculated relative to the actual weight of the workpiece 40 being lifted and lowered loaded on the carriage 10 (approximate workpiece weight WT). Determine whether it is excessive. That is, as described above, the workpiece weight estimate memory 36 stores the workpiece weight estimate WT calculated during the transfer by the workpiece transfer machine 18 of the loading station 17 with respect to the workpiece 40 currently loaded on the carriage 10. is stored (step W11 in FIG. 4). Then, the crane abnormality determination unit 28 reads out the estimated work weight WT for the work 40 currently loaded on the carriage 10 from the estimated work weight memory 36 based on the work number, and calculates the estimated work weight WT by the work weight conversion unit 27. Lifting motor 1
The workpiece weight conversion load factor WT' of No. 2 is compared with the read workpiece weight estimate WT (the workpiece weight estimate WT is regarded as the actual weight of the workpiece 40 and compared). It is determined whether the load on the lifting motor 12 (workpiece weight conversion load ratio WT') is excessive with respect to the actual weight (approximate workpiece weight WT) of the workpiece 40 loaded on the carriage 10 and being lifted and lowered. Note that the approximate workpiece weight WT calculated based on the electric power value of the transfer motor 19 is not regarded as the actual weight of the workpiece 40;
Accurately measure the actual weight of the workpiece 40 in advance.
The accurate measurement value of the weight of the workpiece 40 is compared with the workpiece weight conversion load factor WT' of the lifting motor 12. It may be determined whether the weight is excessive compared to the actual weight. In addition, the actual weight of the workpiece 40 (approximate workpiece weight value WT or accurate measurement value) is calculated from the electric power value (or current value)
Alternatively, the workpiece weight converted into electric power value (or workpiece weight converted into current value) or the workpiece weight converted into load factor is calculated in advance and stored in a memory means by converting it into a load factor.
The current power value (or current value) of the lifting motor 12 measured by the current transformer 12a during lifting is directly or converted into a load factor (without converting to the work weight conversion load factor WT'). An abnormality in the load of the lifting motor 12 may be determined by comparing the weight of the workpiece in terms of electric power value (or the weight of workpiece in terms of current value) or the weight of the workpiece in terms of load factor.

The load on the lifting motor 12 while it is being driven (workpiece weight conversion load ratio WT') is excessive compared to the actual weight of the lifting and lowering workpiece 40 loaded on the carriage 10 (approximate workpiece weight WT). If it is determined that there is an abnormality (therefore, some abnormality has occurred in the elevating system of the carriage 10), the process proceeds from step S22 to step S23, and the main control unit 21 stops the stacker crane 6 via the crane control unit 26. At the same time, in step S24, the warning device 31a issues a warning to the operator via the warning device control unit 31, and further, in step S25, maintenance inspection data such as oil change timing is read out from the crane management data memory 32. The data is then displayed on a CRT display or the like of the input/output device 22a via the input/output control section 22. In other words, even if the operator does not perform maintenance and inspection properly, such as by continuing to operate the stacker crane 6 without carrying out maintenance and inspection, if the load on the lifting motor 12 becomes abnormal, the stacker crane 6 will stop working. Stop. Therefore, the occurrence of any abnormality that may be a sign of an accident such as oil shortage is prevented from being overlooked, and serious accidents such as damage to the carriage 10 etc. can be prevented when the workpiece 40 is raised and lowered by the stacker crane 6. can be prevented from occurring. In this case, the operator inspects the stacker crane 6 to discover the specific location of the failure.

Furthermore, it is determined that the load on the lifting motor 12 (workpiece weight conversion load ratio WT') is appropriate for the actual weight of the workpiece 40 loaded on the carriage 10 (approximate workpiece weight value WT). If this is the case (that is, if the difference between the workpiece weight conversion load factor WT' and the estimated workpiece weight value WT is within the error range), the process proceeds from the aforementioned step S22 to step S26, and the main control section 21 controls the crane control section. 26
The operation of the stacker crane 6 continues via the . Then, in step S27, when the operation of the stacker crane 6 is completed, the main control unit 21 ends the crane check program CCP.

In the above-described embodiment, when transporting the workpiece 40 from the loading station 17 to the stocker 5, the elongation X of the lifting chain 13 is calculated to determine whether the lifting chain 13 needs to be replaced. As described above, not only in the case of the above-mentioned embodiment, but also when transporting the workpiece 40 from the stocker 5 to the machine tool 2, the extension length X of the lifting chain 13 is calculated and the lifting chain 13 is replaced. Of course, it is possible to determine the necessity of In the above-described embodiment, when transporting the workpiece 40 from the loading station 17 to the stocker 5, the workpiece weight conversion load factor WT' of the lifting motor 12 which is being driven is the workpiece weight loaded on the carriage 10.
Detecting the occurrence of an abnormality in the stacker crane 6 by comparing the estimated workpiece weight WT with respect to 0 has been described. However, in the workpiece weight estimation value memory 36, not only the workpiece weight estimation value WT regarding the newly set up workpiece 40 at the loading station 17 but also the workpiece weight estimation value WT shown in FIG.
The approximate workpiece weight WT for each workpiece 40 stored in the stocker 5 of the automated warehouse 3 shown in FIG. 3 is stored in a readable form based on the workpiece number. Therefore,
Not only in the case of the above-mentioned embodiment, but also when transporting the workpiece 40 from the stocker 5 to the machine tool 2, the workpiece weight conversion load factor WT' of the lifting motor 12 being driven is calculated and the workpiece is loaded onto the carriage 10. The stacker crane reads out the estimated work weight WT for the work 40 currently being loaded from the estimated work weight memory 36 based on the work number, and compares the work weight conversion load factor WT' with the estimated work weight WT. It is possible to detect the occurrence of abnormality No. 6.

[0025]

As explained above, according to the present invention, there is provided a loading section such as a carriage 10 and a fork 11 for loading cargo such as a workpiece 40, and the loading section is moved up and down. In a multi-dimensional automated warehouse such as an automated warehouse 3, which is equipped with a crane such as a stacker crane 6 for loading and unloading cargo into and out of shelves such as the work storage shelf 5a, cargo is moved horizontally to the work setup position. A load transfer means such as a work transfer machine 18 for transferring the load from a load carry-in position such as 17a to a load transfer position to the crane such as a work transfer position 17b is provided, and a transfer motor 1 drives the load transfer means.
A motor such as No. 9 is provided, and while the load is being transferred by the load transfer means, the electric power equivalent amount (power, current, etc.) of the motor is measured, and a weight corresponding value (workpiece) corresponding to the weight of the load being transferred is determined. Approximate weight WT, load factor, power value, current value, etc.)
A current transformer 19a, a workpiece weight conversion unit 24, a workpiece weight conversion parameter memory 33, and other weight corresponding value determining means are provided, and with respect to the weight corresponding value, an upper limit value (upper limit parameter LP) corresponding to the maximum loading weight of the crane is provided. , maximum weight converted into load factor, maximum weight converted into electric power value, maximum weight converted into current value, etc.), upper limit value storage means such as an upper limit parameter memory 34 is provided, and the weight corresponding value determined by the weight corresponding value determination means and the upper limit value storage means are provided. Overweight determining means such as an overweight determining unit 25 is provided for comparing the weight with the upper limit value stored in the upper limit value storage means and determining whether the weight of the load being transferred is not excessive for the crane. , overweight warning means such as a warning device control unit 31 and a warning device 31a are provided, which issue a warning when the weight of the load being transferred is determined by the overweight determining means to be excessive for the crane; Therefore, when a load that is too heavy for the crane is carried into the load transfer means, the amount of electric power equivalent to the motor that drives the load transfer means increases when transferring the load, and automatically, A warning will be issued to the worker. Therefore,
Even if the weight of the cargo is not measured by the worker in advance, this system prevents overweight cargo from being loaded onto the crane, and prevents it from being loaded onto the crane. It is possible to prevent serious accidents such as damage to the loading section of the crane from occurring.

Further, the present invention provides a multi-level automated warehouse such as an automated warehouse 3 equipped with a crane such as a stacker crane 6 for loading and unloading cargo such as workpieces 40 to and from shelves such as the workpiece storage shelf 5a. A loading section such as a carriage 10 and a fork 11 for loading cargo is provided so as to be movable up and down, and a motor such as a lifting motor 12 for driving the loading section up and down is provided. Current transformer 1 that measures electric power equivalent (power, current, etc.)
A power equivalent amount measuring means such as 2a is provided, and a weight corresponding value (approximate work weight value WT,
A weight-corresponding value storage means such as a workpiece weight approximate value memory 36 storing accurate measurement values of weight, load factor converted workpiece weight, electric power value converted workpiece weight, current value converted workpiece weight, etc.) is provided to measure the electric power equivalent amount. A workpiece weight conversion unit 27 that determines whether the electric power equivalent amount of the motor measured by the means is excessive with respect to the weight corresponding value of the cargo being lifted and lowered stored in the weight corresponding value storage means; and a crane abnormality determination unit. section 28, an abnormal load determination means such as a work weight conversion parameter memory 35, and the abnormal load determination means:
Abnormality occurrence warning means such as a warning device control unit 31 and a warning device 31a are provided to issue a warning when the amount of electric power equivalent to the motor is determined to be excessive with respect to the value corresponding to the weight of the load being lifted and lowered. With this configuration, if an abnormality occurs in the crane that could be a sign of an accident, such as running out of oil, the amount of electric power for the motor that drives the loading section increases relative to the value corresponding to the weight of the load, and the work is automatically stopped. A warning will be issued to the person. Therefore, even if maintenance and inspection are not performed properly by the operator, it is possible to prevent serious accidents from occurring when lifting and lowering cargo with the crane.

The present invention also provides a multi-level automated warehouse such as an automated warehouse 3 equipped with a crane such as a stacker crane 6 for loading and unloading workpieces 40 and the like to and from shelves such as the workpiece storage shelf 5a. A loading section such as a carriage 10 and a fork 11 for loading cargo is provided to be able to move up and down, and a motor such as a lifting motor 12 for driving the loading section up and down is connected to the loading section via a chain such as a lifting chain 13. A chain position measuring means such as a lifting encoder 15 which is connected to each other and measures the position of the chain is provided, a position detecting means such as an origin sensor 16 which detects the position of the loading section is provided, and the chain position measuring means A chain extension calculation unit 29 or the like for calculating the extension of the chain based on the measured chain position and the position of the loading section detected by the position detection means is provided, Chain management data memory 3 that stores limit judgment values (chain length L, etc.) regarding the extension amount.
A limit judgment value storage means such as No. 7 is provided, and the chain elongation calculated by the elongation calculation means is compared with the limit judgment value stored in the limit judgment value storage means, and it is necessary to replace the chain. A warning device control section 31 and a warning device 31a are provided, and when the chain replacement determining means determines that the chain needs to be replaced, a warning device control section 31 and a warning device 31a are provided.
Since the structure is equipped with chain replacement warning means such as is emitted. Therefore,
Even if a chain is not properly replaced by a worker, it is possible to prevent a serious accident from occurring when lifting or lowering cargo with a crane.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a stacker crane and a loading station of an automated warehouse to which an accident prevention device according to the present invention is applied.

FIG. 2 is a control block diagram of the automated warehouse shown in FIG. 1.

FIG. 3 is a diagram showing the relationship between motor current or power and load factor.

FIG. 4 is a flowchart showing a workpiece weight check program.

FIG. 5 is a schematic diagram showing a method for measuring chain elongation.

FIG. 6 is a flowchart showing a crane check program.

7 is a perspective view of machine tool equipment equipped with the automatic warehouse shown in FIG. 1. FIG.

[Explanation of symbols]

3... Three-dimensional automatic warehouse (automated warehouse) 5a... Shelf (work storage shelf) 6... Crane (stacker crane) 10... Loading section (carriage) 11... Loading section (fork) 12... Motor (for lifting) Motor) 12a...Power equivalent amount measuring means (current transformer) 13...Chain (lifting chain) 15...Chain position measuring means (lifting encoder) 1
6... Position detection means (origin sensor) 17a... Loading position (work setup position) 17b...
Luggage delivery position (workpiece transfer position) 18...Luggage transfer means (workpiece transfer machine) 19...Motor (transfer motor) 19a...Weight corresponding value determining means (current transformer) 24...Weight corresponding value determining means ( Workpiece weight conversion unit) 25...Overweight determination means (overweight determination unit) 27...Abnormal load determination unit (workpiece weight conversion unit) 28...Abnormal load determination unit (crane abnormality determination unit) 29...Extension calculation Means (chain extension calculation section) 30...Chain replacement judgment means (chain extension judgment section) 31...Overweight warning means, abnormality occurrence warning means,
Chain replacement warning means (warning device control unit) 31a... Overweight warning means, abnormality occurrence warning means, chain replacement warning means (warning device) 33... Weight corresponding value determination means (work weight conversion parameter memory) 34... Upper limit Value storage means (upper limit parameter memory) 35
... Abnormal load judgment means (work weight conversion parameter memory) 36 ... Weight corresponding value storage means (work weight approximate value memory) 37 ... Limit judgment value storage means (chain management data memory) 40 ... Cargo (work)

Claims (3)

[Claims] Claim 1: A three-dimensional automatic warehouse having a loading section for loading cargo, and a crane for moving the loading section up and down to take the cargo into and out of the shelf, in which the cargo is loaded.
Providing a cargo transfer means for horizontally moving the cargo from the cargo loading position to the cargo delivery position to the crane,
A weight correspondence method that includes a motor that drives the baggage transfer means, and measures an amount of electric power equivalent to the motor while the baggage is being transferred by the baggage transfer means to obtain a weight corresponding value corresponding to the weight of the baggage being transferred. A value determination means is provided, and an upper limit value storage means is provided for storing an upper limit value corresponding to the maximum loading weight of the crane with respect to the weight corresponding value, and the weight corresponding value determined by the weight corresponding value determination means and the upper limit value are provided. Overweight determining means is provided for determining whether the weight of the load being transferred is excessive for the crane by comparing the weight with an upper limit value stored in the storage means, and the overweight determining means determines whether the weight of the load being transferred is A crane accident prevention device comprising an overweight warning means that issues a warning when it is determined that the weight of the cargo inside is too large for the crane. 2. A multi-level automatic warehouse equipped with a crane for loading and unloading cargo from and to shelves, wherein the crane is provided with a loading section for loading cargo that can be moved up and down, and a motor that drives the loading section up and down. , further comprising a power equivalent amount measuring means for measuring an amount of electric power equivalent to the motor while the load is being lifted and lowered by the crane, and a weight corresponding value storage means storing a weight corresponding value corresponding to the weight of the load being lifted and lowered. , abnormal load determination for determining whether the electric power equivalent amount of the motor measured by the electric power equivalent amount measuring means is excessive with respect to the weight corresponding value of the luggage being lifted and lowered stored in the weight corresponding value storage means; and abnormality occurrence warning means for issuing a warning when the abnormal load determining means determines that the amount of electric power equivalent to the motor is excessive with respect to the value corresponding to the weight of the load being lifted and lowered. Configured crane accident prevention device. 3. A multi-level automatic warehouse equipped with a crane for loading and unloading cargo from and to shelves, wherein the crane is provided with a loading section for loading cargo so as to be movable up and down, and a motor for driving the loading section up and down, A chain position measuring means is provided connected to the loading section via a chain and measures the position of the chain, a position detecting means is provided for detecting the position of the loading section, and the chain position measuring means measures the position of the loading section. an extension calculating means for calculating the extension of the chain based on the position of the chain and the position of the loading section detected by the position detection means; A judgment value storage means is provided, and the chain elongation calculated by the elongation calculation means is compared with a limit judgment value stored in the limit judgment value storage means to determine whether the chain needs to be replaced. A chain replacement determination means is provided, and when the chain replacement determination means determines that the chain needs to be replaced,
A crane accident prevention device that includes a chain replacement warning means that issues a warning.