JP2880206B2 - Automatic stacker crane return method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for controlling an automatically operated stacker crane for an automatic warehouse, and more particularly to a method for resetting when the operation is stopped due to abnormality detection.

[Conventional technology]

The stacker crane travels while detecting its own position, and carries out cargo handling between the shelf and the entrance / exit by automatic operation.

For this reason, the stacker crane is provided with various safety devices. For example, it is provided with a load detector for detecting whether the position and posture of the load placed on the stacker crane is normal. In addition, when the stacker crane stops at a loading / unloading port or shelf for cargo handling, a detector for detecting whether or not the stacker crane has stopped at a predetermined position is provided. Further, a pulse encoder or the like is provided to detect the own running position, but it is possible to detect a count error of this pulse. In addition, a detector is provided for detecting the amount of protrusion of the fork of the fork device for transferring a load.

When these detectors detect an abnormality, the automatic operation is stopped. (Japanese Unexamined Patent Publication No. 58-26703) Also, in the case of a power failure, automatic operation is stopped.

In the event of a stop due to such an abnormality, especially in the case of a stop due to a count error or power outage, the administrator goes to the stacker crane, performs necessary emergency treatment, and then travels to the home position by manual operation. The running position is initialized (reset), and a start-up operation is performed.

The origin position is a reference position for detecting a traveling position, and is generally located at an end of a traveling path.

If the stacker crane is abnormal and you try to store the load on the shelf twice, or if you try to remove the load from the shelf and there is no load, the automatic return operation to the origin is performed. I have.

[Problems to be solved by the invention]

As described above, when a load is to be stored twice on the shelf or when there is no load when trying to remove the load from the shelf, an automatic return operation to the origin can be performed.

This is because the current position is stored in the control device of the stacker crane.

Therefore, in the event of a momentary power failure or power outage due to lightning, if the manufacturing equipment is backed up with a battery or the like so that the current position can be maintained, automatic operation continuation and automatic recovery can be performed even if a momentary power failure or power outage occurs. It seems that driving is possible.

However, if a momentary power failure or power outage occurs while the stacker crane is running, it moves by inertia even during the power outage, so in order to correctly detect the current position, the equipment for detecting the current position is powered off during power outage. It is also necessary to energize. That is, it is not sufficient to energize only the storage device of the control device. For this reason, in order to enable automatic operation at the time of a power failure, a stacker crane needs a generator facility.

Therefore, conventionally, when an instant or power failure occurs, the operation of the stacker crane is stopped, and the operation of returning to the origin is manually performed.

An object of the present invention is to enable automatic return to the origin even in the case of a momentary power failure or power failure.

[Means for solving the problem]

In order to achieve the above object, the present invention provides an automatic stacker crane that detects an instantaneous blackout such as lightning or power failure and stops the operation of the stacker crane, and then automatically returns the stacker crane to the origin in the traveling direction. In the return method, the position of the fork of the fork device installed on the elevating body of the stacker crane is determined, and the fork tip is located between the first strikers provided on the left and right with respect to the direction in which the fork projects and retracts. If the fork is located at the center position when the striker 2 is detected, if there is no fork at the center position and the fork can be returned to the center position, the fork is returned to the center position and the host computer instructs automatic operation. Then, the stacker crane is moved toward the origin of the traveling direction, and a position marker in the traveling direction comprising a third striker provided on the traveling path is provided. Is detected, the current position in the traveling direction of the stacker crane is initialized, and then the elevating body provided on the stacker crane is moved up and down, and the current position is detected from a plurality of position marks formed by the fourth striker of the stacker crane. When the detected current position corresponds to the lowermost position mark of the plurality of position marks, the current position in the ascending / descending direction is initialized and the operation returns to the normal operation.

[Action]

If the fork is returned to the center, the stacker crane can be returned to the origin, so that it can be returned automatically.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 4 shows the entire structure of the automatic warehouse. The stacker crane 10 travels between the two rows of three-dimensional shelves 50, 50, and transports a load between the entrance / exit port 55 and the shelves of the three-dimensional shelf 50. This transport command is issued by the host computer 70 via the optical transmission device 60. In addition, the stacker crane 10 reports the cargo handling status, the presence or absence of an abnormality, and the content to the host computer 70.

FIG. 5 shows the configuration of the stacker crane 10. The stacker crane 10 is a traveling body having a traveling device 11.
12, pillars 13, 13 standing up there, a hoisting device 15 for raising and lowering a lifting body 14 suspended from the upper end of the pillars 13, via a rope, and a fork device 16 installed on the lifting body 14. And a control device 18 for operating each device based on various detection means and data of the host computer 70 and notifying the host computer 70.

As shown in FIGS. 6 and 7, the lifting body 14 has photoelectric loading detectors 21a and 21b for detecting the presence / absence of the load 80. Wire 22a, a package shape detector 22 that detects the presence or absence of a surface of the wire 22a
b, It has a photoelectric type first-come-for-presence detector 23 for detecting whether or not a load is stored on a shelf.

In FIG. 5, the traveling body 12 has a pulse encoder 31 that generates a pulse by rolling on a traveling path. By counting the pulses, the stacker crane 10 recognizes the current position.

In FIG. 8, reference numeral 32 denotes an origin striker set at a position serving as a reference point for traveling, which is located at one end of the traveling path. Reference numeral 33 denotes a deceleration striker, which is provided from a position on the upstream side of the origin striker 32. The origin striker 32 is detected by an optical origin detector 32a installed on the traveling body 12. When the origin striker 32 is detected, the current position obtained by the pulse encoder 31 is initialized (reset) to a predetermined value. The deceleration striker 33 is detected by an optical deceleration detector 33a installed on the traveling body 12. When the deceleration striker 33 is detected, the traveling deceleration is started.

FIG. 9 shows a means for detecting the elevating position of the elevating body 14. As shown in FIG. Pillar 13 of stacker crane 10 has three-dimensional shelf
The strikers 35, 35,... For detecting the shelves are provided corresponding to the cargo receiving positions of the 50 shelves. Striker 3
5 is a set of two strikers 35a and 36b. Striker
35a and 35b are vertically long plates, and the length in the vertical direction is the same. However, the positions of the upper and lower ends are set to a predetermined amount (H ₁
H ₂ ) It is staggered. H ₁ and H ₂ are the same.

Reference numerals 35a and 35b denote optical detectors for detecting the strikers 35a and 35b, respectively. The current position is obtained by obtaining the number of detections of the strikers 35a and 35b by the detectors 36a and 36b.

The elevating body 14 needs to be stopped at each of the shelves at two points above and below the cargo receiving seat. The position that stops above the cargo receiving seat is called the upper level. The upper level is the position where the loaded fork device 16 is moved in the horizontal direction. On the other hand, the position that stops below the cargo receiving seat is called the lower level. The lower level is a position where the unloaded fork device 16 is moved in the horizontal direction.

Describing a case where the load is stored on the shelf, the lifting body 14 is stopped at the upper level position of the corresponding shelf, and the fork device 16 on which the load is loaded is projected toward the shelf. Next, when the elevating body 14 is lowered, the load of the fork device 16 is placed on the load receiving seat of the shelf. Further, the elevating body 14 is lowered and stopped at the lower level. In this state, the fork device 16 is moved backward.

When unloading from the shelves, use a fork device 16 at the lower level.
To raise the elevating body 14 to the upper level, and in this state, the fork device 16 is retracted.

Top position only detector 36a has detected level range H ₁
A nice, two detectors 36a, 36b is referred to as a mid-level range H ₂ the position is detected, a position where only the detector 36b is detected that the lower level range H _3.

The position of the cargo receiving seat on the lowermost shelf is the origin of the elevating body 14. Reference numeral 37 denotes an origin striker provided at the position of the origin. The origin detector 37a provided on the lifting body 14 is the origin striker 3
When 7 is detected, the current position of the lift 14 is initialized (reset) to the lowest position. Reference numeral 38 denotes a striker for forcible deceleration, and when the detector 38a mounted on the elevating body 14 detects this, the forcible deceleration is performed.

FIG. 10 shows a configuration for detecting the position of the fork of the fork device 16. The detector and striker shown here are provided on a fork projecting in the horizontal direction and a base supporting the fork. Centered on fork (fork origin)
, A detector 41a for detecting the striker 41, and a striker 42, 43 for indicating that the fork protrudes to the left or right end, and a detection for detecting this Containers 42a, 43a, striker to indicate that the fork protrusion is between the center and the tip
44, 45, and detectors 45a, 45a for detecting this. The state in which the detector 41a detects the striker 41 is the state in which the fork is located at the center, and the stacker crane 10 can travel only at this time.

The control device 18 determines these signals and performs automatic operation control such as storage and unloading of the load 80 according to a work command from the local area.

If an abnormality occurs during automatic operation, the stacker crane 10 stops abnormally.However, the method of returning to the automatic operation afterwards is generally described as follows.
Only when the position of the stacker crane 10, the elevating body 14 and the fork 16 is accurately stored by the control device 18 when there is a load at the place where the vehicle 80 is dropped, the operation until automatic restart is controlled without manual intervention. be able to.

According to the present invention, even if the position data stored in the instantaneous power failure or power failure special control device 18 is erased, automatic operation is restarted even if no person enters the automatic warehouse unless there is a mechanical or electrical failure. The purpose is to be able to.

Hereinafter, this will be described with reference to the flowcharts of FIGS.

When an abnormality occurs, the stacker crane 10 abnormally stops. When an abnormal stop is performed, the stacker crane 10 notifies the host computer 70 of the abnormal stop and the details thereof. This may be performed by a request from the host computer 70.

When an abnormal stop is performed, the stop is continued until there is a manual command or a command from the host computer 70. The manager grasps the cause of the abnormal stop and instructs whether or not to restart the automatic operation. In the case of double storage of the load or absence of the load to be carried out, a command is issued to restart the automatic operation. Also, in the case of an instantaneous power failure or a power failure as in the case of the present invention, the restart of the automatic operation is commanded via the host computer 70. Hereinafter, the latter case will be described with reference to FIGS.

In FIG. 1, when an abnormal stop occurs, it is first determined whether or not various motors for operating in block A are rotatable, and if possible, it is determined in block B whether there is a risk of causing abnormalities such as abnormal packing. If not, the observer is notified in block H that automatic control is impossible.

After it is determined that the motor can be rotated mechanically and electrically by blocks A and B, in this embodiment, in consideration of safety and data management of the stored load, a command from the ground operator or the host computer 70 is sent to block D. wait.

When the home return command is received from the host computer 70, the stacker crane 1 is returned to the home position in the order shown in block E.

In FIG. 2, in block E1, control is performed to position the fork at the stop position in order to avoid interference with the shelf.

In FIG. 3, it is determined in block E1a whether the fork is at the center. Block E1 if other than fork center
The lifting position is determined by b, but if it is located between the lifting and lowering addresses, that is, if both the detectors 36a and 36b do not detect the striker in FIG. 9, there is a risk that the fork will interfere with the shelf. Because there is, the process ends.

In block E1c, the fork is in the upper level position, that is, when the detector 36a detects and 36b does not detect, or in the lower level position, that is, when the detector 36a does not detect 36b.
Since the fork 5 cannot be operated except when is detected, the level is determined. "Yes" is a top level range H ₁ or lower level range H _3. "No" is an intermediate level range H _2, moves to block E 1 d.

In the block E1d, when the fork 5 is at a position other than the right or left outgoing end (meaning that the detector 42a or 43a is detecting), the elevating operation cannot be performed, so that determination is made. If the fork is at the leading end position, the fork is lowered at a low speed to the lower level position in block E1e to return the fork to the center. If a load is placed on the fork, it will be placed on the load receiving seat. Block E1d
If "No", the process ends.

Blocks E1f to E1i show processing for returning the fork to the center position. If the fork is not at the end position, return to the center at low speed to prevent overrun at the center. If it is at the end, it starts at a high speed for a certain time to reduce the cycle time, and then returns to the center at a low speed.

In FIG. 2, if the fork is at the center position in block E2, the next operation is possible, and if it is not the center position, the center return operation is impossible.

Blocks E3 to E7 show a return operation to the traveling origin position 32, which is a traveling reference point. The traveling control is performed at a high speed until the detector 33a detects the striker 33, and then switches to a low speed when the striker 33 is detected, and is stopped by detecting the origin striker 32. The striker 33 is the running origin position 32
To a length where the speed will be low by then.

Blocks E8 to E13 show a return operation to the elevation origin position (the position of the lowermost striker 35) which is a reference point for elevation. Detector that commands the forced decelerator of descent as well as traveling
Lower at high speed until 33a detects striker 38,
If detected, switch to low speed. The striker 38 is set at a length at which the speed becomes low before the vertical origin position.

There is a range of upper level and lower level even at the origin position, but if there is a load 80 on the fork, the load detection 21a, 21b will work, so when loading, stop at the position where the upper level is detected, and when not loading Stops at the position where the lower level is detected.

In FIG. 1, it is determined in block F whether or not the home position return has been completed by the above control, and if the return has been completed normally, the controller 18 initializes the data and informs the ground that the automatic operation is possible in block G to the ground. Send and end abnormal processing.

If the return of the fork to the center position, the return of the lifting body to the origin, or the return of the stacker crane to the origin cannot be performed, a signal indicating that automatic operation cannot be resumed in block H is output to the host computer. . In this case, the operator takes necessary measures and returns to the origin manually.

According to the present embodiment, there is an effect that the stacker crane 10 can automatically return to the origin position after the occurrence of the abnormality and restart the automatic operation without performing the manual abnormality recovery.

When returning to each origin, only low-speed movement may be performed.

〔The invention's effect〕

According to the present invention, even when an abnormal stop is performed due to a power failure or the like and the data at the current position is lost, it is possible to automatically return to the origin and restart the operation again automatically.

[Brief description of the drawings]

FIG. 1 is a control flowchart of one embodiment of the present invention, and FIG.
FIG. 3 is a detailed flowchart of block E in FIG. 1, FIG. 3 is a detailed flowchart of block E1 in FIG. 2, FIG. 4 is a plan view showing the entire configuration of the automatic warehouse, FIG. FIG. 6 is a plan view of the lifting body of the stacker crane, FIG. 7 is a front view of FIG. 6, FIG. 8 is a layout diagram of a traveling detector, FIG. 9 is a layout diagram of a lifting detector, FIG. FIG. 4 is a layout diagram of a detector of a fork position. 10 ... Stacker crane, 14 ... Lifting body, 16 ... Fork device, 32 ... Travel origin striker, 37 ... Travel origin striker, 42 ... Fork center position detection striker, 21a, 21b, 22b, 23,32a, 33a, 33b, 36a, 36b, 37a, 38a, 41
a, 42a, 43a, 44a …… Detector

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B65G 1/00-1/20

Claims (1)

(57) [Claims] 1. A method for automatically returning a stacker crane to an origin in a traveling direction after detecting an abnormality such as an instantaneous power failure or a power failure due to lightning or the like, and automatically returning the stacker crane to an origin in a traveling direction. A state in which the position of the fork of the fork device installed on the elevating body is determined, and the tip of the fork is located between the first strikers provided on the left and right with respect to the direction in which the fork projects and retracts, and the second striker is detected. When the fork is at the center position, when there is no fork at the center position and the fork can be returned to the center position, the fork is returned to the center position and the host computer instructs automatic operation, and the origin in the traveling direction is returned. The stacker crane toward the vehicle, and detects the position mark in the traveling direction consisting of the third striker provided on the traveling path. The current position in the traveling direction of the lane is initialized, and then the lifting / lowering body provided on the stacker crane is moved up and down to detect the current position from a plurality of position marks formed by the fourth striker of the stacker crane. When the current position corresponds to the lowermost position mark of the plurality of position marks, the current position in the elevating direction is initialized, and the operation returns to normal operation.