JP3163898B2 - Emergency stop device of stacker crane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stacker crane and, more particularly, to a stacker crane emergency stop device for preventing an overrun at the end of a traveling / elevating path of the stacker crane.

[0002]

2. Description of the Related Art With regard to control for preventing overrun at the end of a traveling / elevating path of a stacker crane, various interlocks are applied for ensuring safety. At present, two shield plates are arranged near the end of the route, and are detected by sensors provided on a lift platform and a traveling vehicle. The first shielding plate is for forced deceleration, and starts deceleration if detected at a high speed (normal operation speed). The second shielding plate is an emergency stop when it is detected while traveling / elevating at a middle speed (a predetermined speed equal to or lower than a high speed). Normally, the stacker crane is decelerated by controlling the output of an inverter that drives a traveling / elevating motor, but a mechanical brake is used for emergency stop.

[0003]

According to the overrun prevention method described above, deceleration is started by detecting the first shielding plate, and even if the speed is slightly overspeed, the second shielding plate is immediately detected. The first shielding plate and the second shielding plate are arranged so that the overrun is not required if the mechanical brake is operated. However, after detecting the first shielding plate and starting to decelerate from high speed, the wheels of the bogie and the lift platform slip, and the vehicle is not sufficiently decelerated until the second shielding plate is detected. It may be overrun.

Accordingly, an object of the present invention is to detect the state earlier even when the normal deceleration is not sufficiently performed due to a slip or the like, and to reduce the running speed without causing overrun.
An object of the present invention is to provide an emergency stop device for a stacker crane that can stop lifting and lowering.

[0005]

According to one aspect of the present invention, there is provided a traveling platform for a stacker crane.
Car or lift platform is located near the end of the travel / lift path
After detecting the forced deceleration shielding plate, reduce the speed to creep speed.
Emergency stop device of a stacker crane that operates during
A is a braking means for braking the traveling vehicle or the lifting platform in a sudden deceleration than normal, a distance measuring means for measuring a remaining distance to the current position from the safety stop position near the end of the running and the lifting path, running a speed detection means for detecting a trolley or lifting table speed, storage means for storing an emergency stop distance of the traveling vehicle or the lifting platform to cause stopping of any speed by braking means, very residual distance corresponding to the current speed The emergency stop device of the stacker crane includes control means for operating the braking means when the distance is shorter than the stop distance.

According to a second aspect of the present invention, the control means indirectly responds to the remaining distance and the current speed by comparing the maximum speed that can be stopped at an emergency stop distance less than the remaining distance with the current speed. The emergency stop device of the stacker crane according to claim 1 is configured such that the emergency stop distance is compared with the emergency stop distance, and the braking means is operated when the current speed is higher than the maximum speed.

[0007] The invention according to claim 3 is a stacker clay.
Vehicle or lift platform near the end of the travel / lift path
After detecting the placed forced deceleration shielding plate, the creep speed
Of the stacker crane that operates during the
A braking device for braking a traveling vehicle or an elevator with a deceleration that is steeper than usual, and a distance measuring device for measuring a remaining distance from a safe stop position near an end of a traveling / elevating route to a current position. And speed detection means for detecting the speed of the traveling vehicle or the lifting platform;
Is determined based on the emergency stop distance from an arbitrary speed of the lift platform to the stop, and storage means that stores the maximum speed for each remaining distance that can be stopped before reaching the safe stop position, and the current speed is the remaining distance And a control means for operating the braking means when the speed is higher than the maximum speed according to the above.

[0008]

The present invention has the above-described structure, and has the following effects.

In the emergency stop device for a stacker crane according to the present invention, the running of the stacker crane is performed.
A row cart or elevator is located near the end of the traveling / elevation path.
After detecting the forced deceleration shielding plate, the creep speed is reduced.
Until the speed increases , the control means activates the braking means so that the traveling speed of the stacker crane can be
Emergency stop is performed by braking the bogie or elevator . The emergency stop distance required for the traveling vehicle or the elevator to stop from an arbitrary speed by the braking means is stored in the storage means in advance. The distance measuring means measures the remaining distance from the safe stop position near the end of the traveling / elevating route to the current position.
The safety stop position is determined by the traveling truck of the stacker crane or
This is a position where the platform can be safely stopped, and is a control limit that does not collide with a physical limit means, for example , a shock absorber provided at the end of the traveling / elevating path. The control means controls the traveling vehicle detected by the speed detection means or
Reads the emergency stop distance according to the current speed of the elevator from the storage means, compares the remaining distance with the current emergency stop distance, and when the remaining distance is shorter, it will overrun with normal deceleration, By activating the braking means, the vehicle can be stopped almost at the safe stop position.

In the emergency stop device for a stacker crane according to the second aspect of the present invention, the control means compares the current speed with the maximum speed that can be stopped at a stop distance equal to or less than the remaining distance to indirectly maintain the remaining speed. Compare the distance and the stopping distance according to the current speed. If the maximum speed is higher than the current speed, overrun will occur during normal deceleration. Therefore, if the braking means is operated, the vehicle can be stopped almost at the safe stop position.

In the emergency stop device for a stacker crane according to the third aspect of the present invention, the traveling of the stacker crane
A row cart or elevator is located near the end of the traveling / elevation path.
After detecting the forced deceleration shielding plate, the creep speed is reduced.
Until the speed increases , the control means activates the braking means so that the traveling speed of the stacker crane
Emergency stop is performed by braking the bogie or elevator . The traveling vehicle or the lifting platform by the braking means Sadamari based on emergency stop distance required before stopping the arbitrary speed, maximum speed of each stoppable residual distance up to the safety stop position is stored in advance in the storage means Keep it. Distance measuring means, run
Measure the remaining distance from the safety stop position near the end of the line / elevation path to the current position. The safety stop position is a position where the traveling cart or the elevator of the stacker crane can safely stop, and collides with a physical limit means, for example , a shock absorber provided at the end of the traveling / elevating path. It is a control limit that does not occur. The control unit reads the maximum speed according to the remaining distance measured by the distance measurement unit from the storage unit, compares the maximum speed with the current speed detected by the speed detection unit, and when the current speed is higher, ,
Since overrun occurs during normal deceleration, the brake can be stopped at a substantially safe stop position by operating the braking means.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment shown in the drawings will be described below.

FIG. 1 is a diagram showing a process of an emergency stop according to an embodiment of the emergency stop device for a stacker crane according to the present invention.

[0014] In the figure, the stacker crane traveling carriage (not shown) is traveling at high speed v _h, approaches the end of the track, usually decrease in by controlling the output of the inverter that drives the travel motor Creep speed v at speed β
_After decelerating to _c and traveling for a while at the creep speed vc, the vehicle stops at the safe stop position.

The deceleration is started by the traveling control device of the stacker crane by a sensor provided on the traveling vehicle. The safety stop position is a predetermined position where the traveling vehicle can stop without colliding with the buffer attached to the end of the track, and the shield plate is placed on the ground so that it can stop at the safe stop position by normal deceleration. Are located. The safety stop position is indicated by another shielding plate.

If sufficient deceleration is not performed due to slippage of the drive wheels, etc., after detecting the deceleration start shielding plate, the mechanical brake provided on the traveling vehicle operates to perform an emergency stop. Mechanical brake is usually not used for the reduction, when stopping at a fixed position from the creep rate V _c, and is what is used to be locked directly traveling vehicle.

By operating the mechanical brake at the time of an emergency stop, it is possible to perform a more rapid deceleration than a normal deceleration by controlling the output of the inverter. For example, if the normal deceleration β has some fluctuation, but is approximately 0.3 m / s ² , the emergency deceleration β _e due to the mechanical brake operation is about 0.6 m / s ² .

[0018] For example, slip remains traveling vehicles fast v _h, assuming that reaches the left time t _e1 not at all decelerated, and operates the mechanical brake, and deceleration at the deceleration beta _e, exceeds safety stop position Stop without. If the vehicle slips at the speed v _n , the mechanical brake operates at time t _en and stops without exceeding the safe stop position.

FIG. 2 is a block diagram showing the control structure of this embodiment.

The control unit 1 controls an inverter 4 for driving the mechanical brake 2 and the traveling motor 3, and can know the traveling speed from the output of the inverter 4. Further, an encoder 5, a sensor 6, and an emergency stop distance data storage device 7 are connected to the control unit 1.

The encoder 5 detects the rotation of a distance measuring roller (not shown) which rotates in contact with the running track, and can detect an accurate running position irrespective of the slip of the driving wheels. it can. The pulse value of the encoder 5, the remaining distance S _r of the control unit 1 to the emergency stop position from the current position
Ask for. The sensor 6 is a photoelectric sensor that detects a shielding plate arranged on the ground along a track, and detects a shielding plate for forced deceleration.

The emergency stop distance data stored in the emergency stop distance data storage device 7 is distance data from the operation of the mechanical brake to the stop at any arbitrary traveling speed. For example, the emergency stop distance data corresponding to the high speed v _h in FIG.
an _e1, emergency stop distance data corresponding to the speed v _n is, S
_en . The emergency stop distance data is divided into digital values v _n (v _h to ₂₅₅ ) divided by 256 from high speed v _h to 0, and the emergency stop distance data S _e1 to v _e correspond to each speed value.
_{Se 255} is stored in the form of a table.

Next, the operation of this embodiment will be described.

FIG. 3 is a flowchart showing the control process of this embodiment. This flowchart shows the sensor 6 detects the forced deceleration shielding plate, until the deceleration creep velocity v _c, or the process until the emergency stop.

The control section 1 controls the output of the inverter 4 to perform normal deceleration (step 1). The control unit 1 detects the speed from the output of the inverter 4 (Step 2), the current speed v _n is shifted to the stop control to stop the deceleration Once decelerated to creep speed v _c (Step 3).

[0026] If the present speed v is not reached creep velocity v _c, to determine the residual distance S _r from the pulse value of the encoder 5, reads the emergency stopping distance S _en in accordance with the current speed v _n from the emergency stopping distance data 7 Te (step 4), emergency stopping distance is compared with S _en and remaining distance S _r (step 5).

[0027] In this case, if is larger residual distance S _r than emergency stopping distance S _en, since it is tentatively determined to be able to stop the safety stop position in a normal deceleration, normal deceleration returns to Step 1 To continue. Conversely, the remaining distance S _r
If towards the emergency stopping distance S _en than is large, the deceleration to the extent that the overrun is usually decelerated is determined not to be sufficiently, thereby immediately operate the mechanical brake 2 (step 6).

As described above, according to the emergency stop device of the stacker crane according to the present embodiment, even if the deceleration at the end of the track is not sufficient due to a slip or the like, the traveling stop is performed without exceeding the safe stop position. Can be done.

Further, since the emergency stop distance _Sen and the remaining distance _Sr are compared, a slip or the like occurs in the normal deceleration, and the emergency stop is not performed just because the speed is too high. , And the frequency of impact on the stacker crane and the articles being conveyed can be minimized. Furthermore, even if to do an emergency stop, is performed when the remaining distance S _r is greater than the emergency stopping distance S _en, can be emergency stop from a minimum speed, that minimize impact Can be.

FIG. 4 is a block diagram showing the configuration of another embodiment of the emergency stop device for a stacker crane according to the present invention. Members having the same functions as in the embodiment of FIG. 2 are denoted by the same reference numerals.

In the figure, a plurality of maximum velocity v _ln stored in advance in the maximum speed data storage device 12 is highly required from the remaining distance S _r and any speed to a safe stop position until stopped by the mechanical brake This is a speed value calculated from the stop distance S _en . That is, the maximum speed v _ln is
Is the maximum speed that can be stopped in an emergency stop distance S _en not exceeding any remaining distance S _r.

FIG. 5 is a flowchart similar to FIG. 3, showing the process of an emergency stop according to the embodiment of FIG.

As in FIG. 3, also in this embodiment, normal deceleration (step 11), speed detection (step 12), current speed v _n
And compares the creep velocity v _c (step 13), further measures a remaining distance S _r (step 14). Then, the control unit 11 sets the emergency stop distance S substantially equal to the remaining distance _Sr.
The maximum speed v _ln corresponding to _en is read from the maximum speed data storage device 12 (step 14).

The read maximum speed v _ln is the current speed v
is compared with _n (step 15). If the maximum speed v
greater than the current speed v _n is more of _ln, since the tentative determination that can be stopped in the safe stopping position in a normal deceleration true, normal deceleration (step 11) is continued. vice versa,
If the current speed v _n exceeds the maximum deceleration v _ln , overrun will occur during normal deceleration, so that the mechanical brake is immediately activated (step 16).

As described above, according to the present embodiment, by comparing the maximum speed v _ln with the current speed v _n , FIG.
The same effect as that of the embodiment can be obtained. The maximum speed v _ln is the emergency stop distance S _{en which} does not exceed the remaining distance S _r
Is the maximum speed that can be stopped at
that is compared with _n it would have indirectly comparing the remaining distance S _r and emergency stop distance S _en.

The embodiments of the present invention have been described above.
It is needless to say that the present invention is not limited to the above embodiments, and can be appropriately modified and implemented within the scope of the present invention.

For example, the illustrated embodiment is applied to the traveling of a traveling truck of a stacker crane, but it is needless to say that the embodiment can be applied to the elevation of a lifting platform. Also,
In the illustrated embodiment, the distance is measured by an encoder that detects the rotation of the touch roller. However, a magnescale or the like may be used.

[0038]

As described above, according to the emergency stop device for the stacker crane according to the first aspect of the present invention, the stacker crane is almost at the safe stop position by comparing the remaining distance and the emergency stop distance. Since the vehicle can be stopped, an accident such as a collision of the stacker crane with the shock absorber due to overrun can be prevented.

According to the emergency stop device for a stacker crane according to the second aspect of the present invention, by comparing the maximum speed with the current speed, the stacker crane can be stopped at a substantially safe position to prevent an accident. it can.

According to the emergency stop device for a stacker crane according to the third aspect of the present invention, the maximum speed and the current speed can be compared, and the stacker crane can be stopped at a substantially safe stop position. Accidents caused by the accident can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a relationship between traveling speed and time for explaining a process of an emergency stop according to an embodiment of an emergency stop device for a stacker crane according to the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment for performing an emergency stop in FIG. 1;

FIG. 3 is a flowchart showing a process of an emergency stop in the embodiment of FIG. 2;

FIG. 4 is a block diagram showing a configuration of another embodiment different from the embodiment of FIG. 2;

FIG. 5 is a flowchart showing a process of an emergency stop in the embodiment of FIG. 4;

[Description of the code] v _h high speed v _n the current speed v _c creep speed β normal deceleration β _e emergency stop deceleration S _en, S _e1 emergency stop distance

Claims (3)

(57) [Claims] 1. A traveling trolley or lift of a stacker crane
The stand is located near the end of the traveling / elevating path
After detecting the shielding plate, before decelerating to creep speed
An emergency stop device of an operating stacker crane, which is a braking means for braking a traveling vehicle or an elevator with a deceleration that is steeper than usual, and a remaining distance from a safety stop position near the end of a traveling / elevating route to a current position. storage means for storing the emergency stop distance to cause stopping of any speed by measuring a distance measuring unit that includes a speed detection means for detecting the traveling vehicle or the lifting platform of the speed, the traveling vehicle or the lifting platform braking means, remaining Control means for activating the braking means when the distance is shorter than the emergency stop distance according to the current speed. 2. The control means indirectly compares the remaining distance with the emergency stop distance according to the current speed by comparing the maximum speed that can be stopped at an emergency stop distance equal to or less than the remaining distance with the current speed. The emergency stop device for a stacker crane according to claim 1, wherein the braking means is operated when the current speed is higher than the maximum speed. 3. A traveling trolley or lifting / lowering of a stacker crane.
The stand is located near the end of the traveling / elevating path
After detecting the shielding plate, before decelerating to creep speed
An emergency stop device of an operating stacker crane, which is a braking means for braking a traveling vehicle or an elevator with a deceleration that is steeper than usual, and a remaining distance from a safety stop position near the end of a traveling / elevating route to a current position. a distance measuring means for measuring a speed detection means for detecting the traveling vehicle or the lifting platform speed, Sadamari based on emergency stop distance until stop of the traveling vehicle or the lifting platform any speed by braking means, the safety stop position A stacker crane including storage means for storing a maximum speed for each remaining distance that can be stopped before reaching, and control means for activating the braking means when the current speed is higher than the maximum speed according to the remaining distance. Emergency stop device.