JPH07149410A - Load height detector and load height detecting method for stacker crane - Google Patents

Abstract

PURPOSE:To provide a load height detector and a load height detecting method for a stacker crane which can accurately detect the height of a load accommodated in a lifting carriage without increasing the number of load height detecting sensors required to be mounted. CONSTITUTION:When a load is accommodated in the lifting carriage 11 of a stacker crane, a sensor bracket 16 for sensors 25a, 25b are lowered so that optical axes La, Lb may make parallel movement. When the optical axes La, Lb are interrupted by the load on the lifting carriage 11, the sensor bracket 16 goes up. When the sensor bracket 16 reaches a height position where the optical axes La, Lb are not interrupted any more by the load on the lifting carriage 11, it is stopped. Such height position of the sensor bracket 16 is detected by a height detector 20 as the height of the load on the lifting carriage 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load height detecting device and a load height detecting method for a stacker crane.

[0002]

BACKGROUND OF THE INVENTION Frame shelves 50 commonly used in automated warehouses.
Are formed on both sides of the passage as shown in FIG. 6, for example. That is, a plurality of struts 51 sandwiches the passage, and front and rear 2
A plurality of load receiving shelves 52a to 52d are arranged between columns adjacent to each other so as to extend in the front-rear direction while facing each other. In addition, the one side portion of the frame shelf 50 shows only the lowermost cargo receiving shelf 52d, and the front side of the drawing is the front side.
The back of the page is the back.

The load receiving shelves 52a and 52b are provided with a large space in the vertical direction, and a large storage portion 53 for storing a high load is formed. Further, the load receiving shelves 52b, 52c, and 52d are formed with a small vertical interval, and a small-sized storage portion 54 for storing a load having a low load height is formed. Then, at the lowermost one end of the frame shelf 50, a loading / unloading port 55 for loading / unloading a load.
Are formed.

A stacker crane 57 that reciprocates on a traveling rail 56 laid on the floor is provided in the passage of the frame shelf 50. The stacker crane 57 includes a traveling platform 58,
A frame 59 having a pair of masts 59a provided on the traveling platform 58 and an elevating carriage 60 arranged so as to be vertically movable between the masts 59a are provided. The mast 5
A crane controller 61 for driving and controlling the stacker crane 57 is provided at 9a.

As shown in FIG. 7, the lift carriage 6 is provided.
Reference numeral 0 denotes a bottom plate 65 and side walls 66a and 66b extending upward from both left and right ends of the bottom plate 65. On the upper surface of the bottom plate 65, the cargo receiving shelves 52a to 52d and the lifting carriage 6 are provided.
Fork device 67 for delivering a load to and from 0
However, it is equipped so that it can reciprocate in the front-back direction. That is, the elevating carriage 60 accommodates the load on the elevating carriage 60 by extending the fork device 67 to place the load from the lower side and retracting the fork device 67 on which the load is placed. Further, by performing the operation reverse to the above, the load placed on the elevating carriage 60 is loaded into each of the storage portions 53,
It is designed to be accommodated in 54.

Side walls 66 of the lifting carriage 60 facing each other.
Of the a and 66b, the first light emitting element 68a is fixed to the upper portions of both outer side surfaces of the one side wall 66a, and the second light emitting element 69a is fixed to a position lower than the first light emitting element 68a. . Further, the first side wall 66b is formed on both outer side surfaces of the other side wall 66b.
Of the first light receiving element 68 at the same height as the light emitting element 68a of
b is fixed, and the second light receiving element 69b is fixed at the same height position as the second light emitting element 69a.

The light emitting elements 68a, 69a and the light receiving elements 68b, 69b are connected to a crane controller 61 provided on the mast 59a, and the light receiving elements 68b, 69b are connected.
Is designed to receive the light emitted from the light emitting elements 68a and 69a at the same height. That is, the first light emitting element 6
An optical axis L1 is formed between 8a and the first light receiving element 68b, and an optical axis L2 is formed between the second light emitting element 69a and the second light receiving element 69b. Each of the light receiving elements 68b and 69b outputs a cutoff signal to the crane controller 61 when the optical axes L1 and L2 are cut off.

[0008] The crane controller 61 determines that the load is a load having a low load and does not operate the stacker crane 57 when the cutoff signal from each of the light receiving elements 68b and 69b is not input during the load removing operation. The load is accommodated in the small-sized accommodating portion 54 by driving. The crane controller 61
When the cutoff signal from the second light receiving element 69b is input during the unloading operation, the load is determined to be a high load,
The stacker crane 57 is driven to store the load in the large-sized storage portion 53.

Further, when the crane control device 61 inputs a cutoff signal from both of the light receiving elements 68b and 69b during the unloading operation, the crane control device 61 judges that the load is too large to be accommodated, and the stacker crane 57. It is designed not to drive.

[0010]

By the way, in the load height detecting device configured as described above, the load accommodated in the elevating carriage 60 is discriminated only into two types, a high load and a low load. Can not. Therefore, when accommodating loads having different load heights on the frame rack 50, loads having different load heights are roughly classified into high load load and low load load in the storage portions 53 and 54, respectively. Is housed. That is, since the loads having the same load height are not always stored in the storage units 53 and 54, the storage units 53 and 54 are preliminarily formed to be large in size so that loads having different load heights can be stored. I have to

However, if each of the accommodating portions 53 and 54 is made larger in advance, there is a problem that the number of loads that can be accommodated in the framework shelf 50 is reduced and the efficiency of housing the framework shelf 50 is reduced.

Therefore, it is conceivable to further increase the number of light emitting elements and light receiving elements to be mounted and to discriminate the load accommodated in the elevating carriage 60 into two or more types according to the load height.
However, the light emitting elements 68a and 69a and the light receiving element 68
Since b and 69b are mounted in small spaces such as the front and rear surfaces of the side walls 66a and 66b, there is a limit to increase the number of mounted light emitting elements and light receiving elements.

The present invention has been made to solve the above problems. A first object of the present invention is to accurately load a load to be accommodated in a lifting carriage without increasing the number of mounted load height detection sensors. An object of the present invention is to provide a load height detection device for a stacker crane that can detect the load height.

A second object is to provide a load height detection method for a stacker crane capable of detecting the accurate load height of the load accommodated in the elevating carriage.

[0015]

In order to solve the above-mentioned problems, the invention according to claim 1 provides a lift carriage of a stacker crane with a load height detection sensor for detecting an upper end of a load accommodated in the carriage. A moving means for moving the load height detecting sensor in the vertical direction, a stopping means for stopping the moving means when the load height detecting sensor detects the upper end of the load, and a moving means for moving the stopping means. When stopped, a measuring means for measuring the height position of the load height detection sensor at that time is provided.

A second aspect of the present invention has the gist that in the load height detecting device for a stacker crane according to the first aspect, the load height detecting sensor is a limit switch. According to a third aspect of the present invention, a light emitting element and a light receiving element are provided on the elevating carriage of the stacker crane, an optical axis is formed between both elements, and the load is changed from the change in the transmission state of the optical axis due to the load stored in the elevating carriage. In a load height detection device for a stocker crane that detects height, a moving means for moving the light emitting element and the light receiving element up and down with respect to an elevating carriage, and stopping the moving means by changing a transmission state of the optical axis. The gist of the present invention is to include stop means and measuring means for measuring height positions of the light emitting element and the light receiving element when the moving means is stopped by the stop means.

According to a fourth aspect of the present invention, in the load height detecting device for a stacker crane according to the third aspect, two pairs of a light emitting element and a light receiving element are provided on the elevating carriage, and the pairs are formed between the elements of each set. The point is that the optical axes intersect each other.

According to a fifth aspect of the present invention, the load height sensor provided on the lift carriage of the stacker crane is lifted from below, and the load height sensor detects the upper end of the load on the lift carriage. The gist is to detect the height of the load on the unloading carriage by stopping the load and detecting the stop height position of the load height sensor.

According to a sixth aspect of the present invention, in the load height detecting method for the stacker crane according to the fifth aspect, the load height detecting sensor provided on the elevating carriage of the stacker crane is lowered so that the load height detecting sensor is When the load on the lift carriage is detected, the load height detection sensor is raised, and when the load height detection sensor detects the upper end of the load, the load height detection sensor is stopped, and the stop height position of the load height detection sensor The gist is to detect the height of the load on the unloading carriage by detecting the.

According to a seventh aspect of the present invention, in the load level detecting method for a stacker crane according to the fifth and sixth aspects, the load level detecting sensor is a sensor including a light emitting element and a light receiving element. To do.

[0021]

Therefore, according to the first aspect of the present invention, when the load is stored in the elevating carriage of the stacker crane, the load height detection sensor provided on the elevating carriage is moved down by the moving means. When the load height detection sensor detects the upper end of the load on the lifting carriage, the moving means raises the load height detection sensor, and stops when the load height detection sensor is above the upper end of the load on the lifting carriage. . The height position of the load height detection sensor at this time is measured by the measuring means as the height of the load on the lift carriage.

According to the second aspect of the present invention, when the load is stored in the lifting carriage of the stacker crane, the limit switch provided on the lifting carriage is lowered by the moving means. When the limit switch detects the upper end of the load on the lift carriage, the limit switch is moved up by the moving means and is stopped when the limit switch is above the upper end of the load on the lift carriage. The height position of the limit switch at this time is measured by the measuring means as the height of the load on the elevating carriage.

According to the third aspect of the invention, when the load is stored in the elevating carriage of the stacker crane, the light emitting element and the light receiving element provided on the elevating carriage are moved down by the moving means so that the optical axes move in parallel. . Then, when the optical axis is blocked by the load on the elevating carriage, the light emitting element and the light receiving element are raised by the moving means, and the light emitting element and the light receiving element are placed at a height position where the optical axis is not blocked by the load on the elevating carriage. Be stopped. The height positions of the light emitting element and the light receiving element at this time are measured by the measuring means as the height of the load on the elevating carriage. Further, since the light emitting element and the light receiving element are raised and stopped depending on the transmission state of the optical axis, the light emitting element and the light receiving element can be raised and stopped at the correct height positions even if the loading place is slightly displaced.

In the invention according to claim 4, since the two optical axes are formed on the elevating carriage so as to intersect with each other, the height of the load can be accurately measured even when the load moves on the elevating carriage. It

According to the fifth aspect of the invention, the load height detecting sensor is raised from below, and when the load height detecting sensor detects the upper end of the load on the elevating carriage, the load height detecting sensor is stopped. . Then, the height of the load on the elevating carriage is detected by measuring the height position of the load height detection sensor at this time. Therefore, the height of the load on the lift carriage is accurately detected.

According to the sixth aspect of the present invention, the load height detecting sensor is lowered, and when the load height detecting sensor detects the upper end of the load on the descending carriage, the descent is stopped and then the load height detecting sensor is raised. It Then, when the load height detection sensor reaches the upper end of the load on the elevating carriage, it is stopped. The height of the load on the elevating carriage is detected by measuring the height position of the load height detection sensor at this time. Therefore, the height of the load on the lift carriage is accurately detected.

According to the invention of claim 7, the light emitting element and the light receiving element provided on the elevating carriage are moved to a height position where the light emitting element and the light receiving element are raised by the moving means and the optical axis is not blocked by the load on the elevating carriage. When it comes, the light emitting element and the light receiving element are stopped. The height positions of the light emitting element and the light receiving element at this time are measured by the measuring means as the height of the load on the elevating carriage.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment embodying the present invention will now be described with reference to FIGS.
It will be described with reference to FIG. As shown in FIG. 3, the framed shelf 1 is composed of a plurality of columns 2 extending in the vertical direction and a cargo receiving shelf 3 protruding from each of the columns 2 so as to face each other. The cargo receiving shelf 3 supports the cargo W. It is like this.
In the frame shelf 1, storage sections 4a to 6f having different heights are sectioned and formed by the columns 2 and the load receiving shelves 3 so that loads W having different heights can be stored. A storage port 5 for loading and unloading the load W is formed in the storage section 4a at the bottom end.

On the floor on which the frame shelf 1 is installed, the frame shelf 1
A traveling rail 6 extending parallel to the frame rack 1 is laid, and an upper rail 7 is arranged at the uppermost portion of the frame rack 1 so as to extend parallel to the frame rack 1. A stacker crane 8 is arranged between the traveling rail 6 and the upper rail 7.
That is, the stacker crane 8 is configured to reciprocate along the traveling rail 6 and the upper rail 7 between the storage units 4a to 6f and the loading / unloading port 5.

The stacker crane 8 is provided with a traveling platform 9, a frame 10 having a pair of masts 10a provided on the traveling platform 9, and an elevating carriage 11 which is vertically movable between the masts 10a. . The mast 10a is provided with a crane controller 12 for driving and controlling the stacker crane 8.

As shown in FIG. 1, the lifting carriage 1
1 is composed of a bottom plate 13 and side walls 14a and 14b extending upward from both left and right ends of the bottom plate 13. On the upper surface of the bottom plate 13, a fork device 15 for transferring a load between the load receiving rack 3 and the elevating carriage 11 is equipped so as to be capable of reciprocating in the front-rear direction. That is, the lifting carriage 1
1, the fork device 15 is extended and the load is placed from below,
The load is accommodated on the elevating carriage 11 by retracting the fork device 15 on which the load is placed.
Further, by performing the operation reverse to the above, the lifting carriage 1
The load placed on the 1 is accommodated in each of the accommodating portions 4a to 4f.

Side walls 14 of the lifting carriage 11 facing each other
A rod-shaped sensor bracket 16 extending in the front-rear direction is provided on the inner surface of one of the side walls 14a and 14b so as to be vertically movable by an elevating device 17 shown in FIG. The elevating device 17 includes a pair of upper and lower gears 18a and 18b, a chain 18c that connects the gears 18a and 18b, and an electric motor 19 that rotates the lower gear 18b. When the electric motor 19 is driven, the sensor bracket 16 mounted on the chain 18c moves up and down. Further, the electric motor 19 has a height detector 20 including a potentiometer for detecting the rotation amount of the electric motor 19 and measuring the height position of the sensor bracket 16.
Is provided.

On the other hand, a guide rail 21 extending vertically is formed on the inner surface of the side wall 14a. The sensor bracket 16 is guided by each of the guide rails 21 so that the sensor bracket 16 can be moved up and down while keeping horizontal.

Sensors 25a and 25b having light emitting elements 23a and 23b and light receiving elements 24a and 24b are provided at both ends of the sensor bracket 16. Reflecting plates 26a and 26b extending in the vertical direction are provided on the inner surface of the side wall 14b that faces the inner surface of the side wall 14a.
Is installed at a predetermined angle so as to face the sensor 25a. Similarly, the reflector plate 26b is also installed so as to face the sensor 25b at a predetermined angle. Reflection tapes 27a and 27b for reflecting the light emitted from the light emitting elements 23a and 23b are provided on the surfaces of the reflection plates 26a and 26b facing the sensors 25a and 25b.

Therefore, the light receiving elements 24a and 24b reflect the light emitted from the light emitting elements 23a and 23b on the reflection tapes 27a and 27b.
Light is received via 27b. That is, the light emitting element 23a and the reflection tape 27a form an optical axis La, and the light emitting element 23b and the reflection tape 27b form an optical axis Lb. The optical axes La and Lb intersect each other and move up and down as the sensor bracket 16 moves up and down. When the light emitted from the light emitting elements 23a and 23b is blocked, the light receiving elements 24a and 24b output a blocking signal (OFF signal), and when the light is not blocked, the light receiving elements 24a and 24b are non-blocking signals ( ON signal)
Is output.

Next, the electrical construction of the load height detecting device will be described. As shown in FIG. 4, the crane controller 12 includes an electric motor 1 for moving the sensor bracket 16 up and down.
9 is connected. Further, the crane control device 12 is connected to the respective sensors 25a and 25b and a height detector 20 for detecting the height position of the sensor bracket 16.

The crane controller 12 drives the electric motor 19 to lower the sensor bracket 16 from the uppermost position when the elevating carriage 11 performs the unloading operation. Each of the sensors 25a and 25b has an optical axis La depending on the load during the unloading operation.
, Lb are shut off, the crane controller 1
A cut-off signal (OFF signal) is output to 2. The crane control device 12 rotates the electric motor 19 in the reverse direction to raise the sensor bracket 16 when a cutoff signal (OFF signal) is input from at least one of the sensors 25a and 25b.

When the sensor bracket 16 moves up to a position where the optical axes La and Lb are not blocked by the load, the sensors 25a and 25b output a non-blocking signal (ON signal), and the crane controller 12 drives the electric motor 19. Stop. When the electric motor 19 stops, the height detector 20
The height position of the sensor bracket 16 at that time (correctly, the height position of the optical axes La and Lb) is detected, and the detection signal is output to the crane controller 12. Crane controller 12
Determines the height of the load based on the detection signal from the height detector 20, and selects the storage units 4a to 4f having the optimum height for the load from the storage units 4a to 4f having different heights. . And
The crane controller 12 drives the stacker crane 8,
Loads are stored in the selected storage units 4a to 4f. The height data of the accommodating portions 4a to 4f is stored in advance in a memory built in the crane control device 12.

Next, the operation of the load height detecting device of the stacker crane 8 configured as described above will be described. When accommodating the load W brought into the loading / unloading port 5 in the frame shelf 1, first, the fork device 15 is extended to the lower side of the load W to raise the elevating carriage 11, and the load W is forked as shown in FIG. Place at position B on device 15. Then, at the same time when the fork device 15 is retracted onto the elevating carriage 11, the crane control device 12 drives the electric motor 19 to lower the sensor bracket 16. Then, the optical axis La
, Lb also descend with the sensor bracket 16.
5 is a cross-sectional view of the elevating carriage 11 of FIG. 3 as seen from the direction of arrow AA, and the broken lines in FIG. 5 indicate the optical axes La and L of the cut surface when the sensor bracket 16 is lowered.
The locus of b is shown.

When the sensor bracket 16 continues to descend, the optical axis La descending when the load W retracted on the elevating carriage 11 is at position C is blocked by the load W, and the sensor 25
a outputs a cutoff signal (off signal) to the crane controller 12. Crane controller 12 has a shutoff signal (off signal)
When is input, the electric motor 19 is rotated in the reverse direction. Therefore, the sensor bracket 16 slightly overruns and then rises.

When the load W is at the position D, the optical axis La that rises is higher than the load height of the load W, and the optical axis La is no longer blocked. Then, the sensor 25a outputs a non-blocking signal (ON signal) to the crane controller 12. At this time, since the optical axis Lb is not blocked, the crane controller 12 inputs a non-blocking signal (ON signal). When the crane control device 12 receives the non-interruption signal (ON signal) from both the sensors 25a and 25b, the crane control device 12 stops the electric motor 19 and stops the sensor bracket 16 from rising.

At this time, the height detector 20 is connected to the electric motor 1
The height position of the sensor bracket 16, that is, the height of the load W is detected from the rotation amount of 9, and the detection signal is output to the crane controller 12. The crane control device 12 selects the accommodating portions 4a to 4f corresponding to the load height of the load W among the accommodating portions 4a to 4f having different heights. Then, the crane device 12 drives the stacker crane 8 to carry the load W to the selected storage units 4a to 4f, and performs the reverse operation of the unloading operation to store the load W in the selected storage units 4a to 4f. To do.

As described in detail above, according to this embodiment, the sensor bracket 16 having the sensors 25a and 25b attached thereto
Was moved up and down. Then, the sensor bracket 16 was stopped at a height position corresponding to the height of the load accommodated in the elevating carriage 11, and the height position of the sensor bracket 16 was detected by the height detector 20. Therefore, it is possible to detect the exact load heights of loads of various heights accommodated in the elevating carriage 11 without increasing the number of sensors.

Further, since the accurate load height of the load can be detected, the frame rack 1 is formed with the accommodating portions 4a to 4f having different heights, and the height of the load is adjusted to an appropriate height according to the load height of the load. Accommodation part 4a
Loads can be stored in ~ 4f. As a result, the housing efficiency of the frame shelf 1 can be improved.

In this embodiment, the sensors 25a and 25b are provided with the light emitting elements 23a and 23b and the light receiving elements 24a and 24b.
Was used as a height detection sensor. And the light emitting element 2
3a and 23b and the light receiving elements 24a and 24b, the electric motor 1 is changed by changing the transmission state of the optical axes La and Lb.
9 was controlled. Therefore, the lift carriage 1
Even if the load on 1 is placed with a slight shift, the accurate load height of the load can be detected.

In the present embodiment, when the fork device 15 on which the load is placed is retracted onto the elevating carriage 11, the sensor bracket 16 is lowered from the uppermost position, and the optical axes La,
When one of Lb is blocked by the load, the sensor bracket 16 is raised. Then, the sensor bracket 16 is stopped at a height position where both the optical axes La and Lb are not blocked, and this height position is detected by the height detector 20 as the load height of the load W. Therefore, it is possible to detect the accurate load height even if the load is moving.

Further, since the sensors 25a and 25b and the reflection plates 26a and 26b are installed so as to intersect the optical axes La and Lb, even if the load is moving, the optical axis La and
Lb is reliably cut off. Therefore, the height of the moving load can be detected more accurately.

In this embodiment, the sensors 25a and 25b are raised to detect the height of the load W, and when the load W no longer blocks the optical axes La and Lb, the sensors 25a and 25b.
Was stopped, and the height position at that time was set as the height of the load W. Therefore, even if the electric motor 19 overruns and stops for some reason, the height of the load W is detected as a relatively large value, and thus the accommodation failure due to accommodation in the accommodating portions 4a to 4f having no height is caused. Does not cause

Furthermore, in this embodiment, the sensors 25a, 25a
b was lowered and then raised. Therefore,
For example, the sensor bracket 16 is rapidly lowered until the cutoff signal (OFF signal) is output, and the cutoff signal (OFF signal) is output.
The electric motor 19 can be controlled to raise the sensor bracket 16 at a low speed after the output of. As a result, the load height can be detected quickly and accurately.

The present invention is not limited to the above embodiment, but may be embodied by being modified as follows. (1) A limit switch may be provided on the sensor bracket 16 instead of the sensors 25a and 25b. in this case,
A limit switch is installed on the sensor bracket 16 so as to come into contact with the side portion of the load accommodated in the elevating carriage 11. Then, when the sensor bracket 16 is lowered and the limit switch comes into contact with the upper end of the load accommodated in the elevating carriage 11, the limit switch is activated by the crane control device 12.
The off signal is output to. When the crane control device 12 receives the OFF signal, it rotates the electric motor 19 in the reverse direction to raise the sensor bracket 16. Then, when the sensor bracket 16 reaches the height position of the upper end of the load, the limit switch does not contact the load and outputs an ON signal to the crane control device 12, and the crane control device 12 causes the electric motor 19 to move.
To stop. When the electric motor 19 stops, the height detector 20 detects the height position of the sensor bracket 16 at that time, that is, the height of the load. Therefore, also in this case, it is possible to detect the accurate load heights of loads of various heights accommodated in the elevating carriage 11.

(2) In this embodiment, the sensors 25a and 25a
When b is lowered from the uppermost position and the optical axes La and Lb are blocked by the load, the sensors 25a and 25b are raised.
The present invention is not limited to this. That is, the fork device 15
The sensor 2 at the same time that
5a and 25b are raised from the lowermost position so that the optical axes La and Lb
When the load is no longer blocked by the load, the sensor 25
You may stop a and 25b. Even in this case, even if the electric motor 19 is overrun for some reason and stopped, the height of the load W is detected as a large value, and thus the load W cannot be accommodated in the accommodating portions 4a to 4f. Will not cause any trouble.

(3) In this embodiment, the light emitting elements 23a, 2a
Although 3b and the light receiving elements 24a and 24b are attached to the same sensor bracket 16, the present invention is not limited to this. That is, the reflectors 26a and 26b are omitted, and the sensor bracket 16 is provided on the inner surface of the side wall 14b so as to be vertically movable, and the light emitting elements 23a and 23b are attached to the sensor bracket 16. Then, the sensor bracket 16 on the side wall 14a side
The light receiving elements 24a and 24b are attached to. in this case,
Each sensor bracket 16 may be moved up and down in synchronization.

(4) In this embodiment, the two sensors 25
Although a and 25b are installed on the sensor bracket 16, the number of sensors may be one or three or more. In this case, the reflectors 26a and 26b may be provided by the number of sensors.

(5) In this embodiment, the reflection plates 26a, 26
b on the surface facing the sensors 25a and 25b of b.
Although 7a and 27b are provided, the reflecting tapes 27a and 27b may be omitted and the reflecting plates 26a and 26b may be formed by mirrors or the like.

(6) The sensors 25a and 25b and the reflectors 26a and 26b do not have to be installed so as to intersect the optical axes La and Lb. For example, the sensors 25a and 25b are attached to the side wall 1
4b, the sensor 25 on the side wall 14b is installed.
Direct reflection tape 27a, 2 on the portion corresponding to a, 25b
7b may be attached. In this case, the reflectors 26a, 2
Since 6b can be omitted, the lift carriage 11
It is possible to reduce the number of parts constituting the.

[0056]

As described in detail above, according to the first and second aspects of the present invention, an accurate load height of the load accommodated in the elevating carriage can be achieved without increasing the number of mounted load height detection sensors. There is an excellent effect that can be detected.

According to the inventions of claims 3 and 4,
Since the sensor including the light emitting element and the light receiving element is used as the load height detection sensor, there is an excellent effect that the load height can be accurately detected even if the load on the elevating carriage is placed with a slight deviation.

According to the fifth, sixth and seventh aspects of the present invention, since the height of the load is detected relatively large even if the rising stop of the detection sensor is delayed, the load is stored in the storage unit having no height. There is an excellent effect that it is possible to prevent the trouble of being unable to be accommodated due to this.

[Brief description of drawings]

FIG. 1 is a perspective view showing a lift carriage of this embodiment.

FIG. 2 is a perspective view showing an elevating device of this embodiment.

FIG. 3 is a side view showing a frame shelf and a stacker crane of this embodiment.

FIG. 4 is a configuration diagram showing an electrical configuration of a load height detection device of this embodiment.

5 is a cross-sectional view of the elevating and lowering carriage of FIG. 3 as seen from the direction of arrow AA.

FIG. 6 is a cutaway perspective view showing a conventional frame rack and stacker crane.

FIG. 7 is a perspective view showing a conventional lift carriage.

[Explanation of symbols]

8 ... Stacker crane, 11 ... Lifting carriage, 12 ...
Crane control device as stopping means, 17 ... Elevating device as moving means, 20 ... Height detector as measuring means,
23a, 23b ... Light emitting element, 24a, 24b ... Light receiving element, 25a, 25b ... Sensor, La, Lb ... Optical axis, W ...
load.

Claims (7)

[Claims] 1. A lifting carriage of a stacker crane,
A load height detection sensor for detecting the upper end of the load accommodated in the carriage, a moving means for moving the load height detection sensor in the vertical direction, and when the load height detection sensor detects the upper end of the load, A stacking height detection device for a stacker crane, which comprises a stopping means for stopping the moving means, and a measuring means for measuring the height position of the load height detection sensor when the moving means is stopped by the stopping means. . 2. The stack height detection device for a stacker crane according to claim 1, wherein the load height detection sensor is a limit switch. 3. A stacker crane elevating carriage is provided with a light emitting element and a light receiving element, and an optical axis is formed between both elements, so that a load height is determined from a change in a transmission state of the optical axis due to a load accommodated in the elevating carriage. In a stacker crane load height detecting device for detecting, a moving means for moving the light emitting element and the light receiving element up and down with respect to an elevating carriage, and a stopping means for stopping the moving means by a change in a transmission state of the optical axis. A stacker crane load height detection device comprising a light emitting element and a measuring means for measuring the height position of the light receiving element when the moving means is stopped by the stopping means. 4. The stack height detection device for a stacker crane according to claim 3, wherein two pairs of a light emitting element and a light receiving element are provided on the elevating carriage, and the optical axes formed between the elements of each set intersect with each other. Stacker crane load height detection device. 5. A load height sensor provided on an elevating carriage of a stacker crane is lifted from below, and when the load height sensor detects the upper end of the load on the elevating carriage, the load height sensor is stopped, Height detection method for stacker cranes that detects the height of the load on the unloading carriage by detecting the stop height position of the height sensor. 6. The load height detection method for a stacker crane according to claim 5, wherein the load height detection sensor provided on the lift carriage of the stacker crane is lowered, and the load height detection sensor loads the load on the lift carriage. When the load height detection sensor is raised when it is detected, the load height detection sensor is stopped when the load height detection sensor detects the top of the load, and the load height detection sensor detects the stop height position of the load. A stacker crane load height detection method for detecting the height of a load on a descending carriage. 7. The stacker crane load height detection method according to claim 5 or 6, wherein the load height detection sensor is a sensor including a light emitting element and a light receiving element.