JP4462950B2 - Unloading control device for unmanned forklift - Google Patents

Description

  The present invention relates to a loading control device for an unmanned forklift when loading a cargo rack with an unmanned forklift in a three-dimensional automatic warehouse.

  FIG. 9 is a schematic configuration diagram of a three-dimensional automatic warehouse, in which a cargo rack building 2 having a large number of cargo racks 1 is erected at predetermined intervals in the horizontal direction and the vertical direction. A guide line 4 is laid on the floor surface of the passage 3 between the adjacent cargo racks 2 to guide the unmanned forklift 10 to travel. The unmanned forklift 10 is instructed by radio or the like from a central control panel (not shown) so that the load 5 is automatically taken out and placed on a load rack of a predetermined load rack building 2.

  In this type of three-dimensional automatic warehouse, the distance between the cargo racks 2 is set slightly larger than the width of the unmanned forklift 10 in order to reduce the installation area, and the unmanned forklift 10 is traveling in the narrow passage 3. Cargo handling work of the load 5 is performed. As is well known, the unmanned forklift 10 is provided with a lift bracket 11 in a mast device that can be raised and lowered, and the lift bracket 11 is provided with a pair of forks 12.

  FIG. 10 shows a diagram for explaining the problem when loading the load 5 on the load rack 1 with the unmanned forklift 10. Here, the addresses of the load rack 1 are, for example, R11, R12, In this case, the load 5a is already stored in the loading rack R13, and the loading 5 is loaded on the loading rack R14 on the upper floor of the loading rack R13 by the unmanned forklift 10. This is a case in which the load 5a stored in the load rack R13 protrudes to the side of the passage 3 for some reason. Normally, the unmanned forklift 10 comes to a position below the load rack R14 and stops, and the load 5 is moved from the position to the fork 12. Lift up at.

  However, if the load 5 is lifted up as it is, it may interfere with the protruding load 5a, causing the both loads to collapse and break. As described above, since the passage 3 between the shelves 2 is set narrow, the unmanned forklift 10 itself cannot be moved in the width direction of the passage 3, and the lifted load 5 protrudes. It will hit the load 5a. In this state, after unloading the load, the load touches the emergency stop tape switch provided on the bumper of the unmanned forklift 10, causing the unmanned forklift 10 to stop traveling, or an error due to traveling overload, etc. It may also be stopped. In addition, there is a problem that it takes a recovery time such as correction in a manned operation in which the unmanned forklift 10 is manually operated after the error stops.

  Moreover, there exists patent document 1 as what detected the obstacle and prevented a collision, for example.

Japanese Patent Laid-Open No. 2004-1992

  In this patent document 1, the collision is prevented by detecting the obstacle in advance, but this is for stopping the forklift, so it is necessary to remove the obstacle once. There is a problem that work must be interrupted and work efficiency is poor.

The present invention has been provided in view of the above-mentioned problems, and provides a loading control device for an unmanned forklift having at least the following objects.
(1) Even if there is an overhanging load, prevent the load from interfering and complete the loading operation.
(2) Improve work efficiency by automatically continuing what has been stopped due to errors until now.

Therefore, in the unloading forklift load storage control device of the present invention, in the unloading forklift load storage control device for transferring and storing the load mounted on the unmanned forklift to a predetermined load shelf, A first sensor that detects whether or not the load that protrudes from the lower loading rack of the storage destination contacts the raised load, and unmanned when traveling with the protruding load When receiving a signal from the second sensor that detects whether or not the forklift is in contact with the first sensor that the loads are in contact with each other, the lift of the load is stopped and the protruding load is not contacted. The unmanned forklift is retracted to the position, and after the retreat, the unloaded forklift is moved forward after the loaded load is raised to the height position of the protruding load. Control means for raising the loaded load to the storage height position when the detection signal from the sensor is not received, and moving the load forward to the storage position after this rise and storing the load on the load shelf by a shift operation. It is characterized by being.

According to the loading control device for an unmanned forklift of the present invention, in addition to the detection of the presence or absence of interference between the loaded load and the loaded load by the first sensor, the second sensor protrudes from the load shelf. Since it is determined whether or not the load and the unmanned forklift interfere with each other, even if there is a load that protrudes from the load shelf, the loaded load can be transported more safely and reliably to the specified storage location. Can be stored. Thereby, the efficiency of the loading operation can be further improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention prevents the collision with the protruding load 5a by adding the following elements to the conventional unmanned forklift 10 side, and allows loading work even if there is an protruding load 5a that becomes an obstacle. The load 5a is stored in a predetermined load shelf 1 while avoiding the protruding load 5a without interruption.

  That is, as shown in FIG. 1 and FIG. 2, a first sensor 21 is provided above the lift bracket 11 of the unmanned forklift 10 via a support member 14, and the first sensor 21 detects an obstacle from a load rack R <b> 13. The protruding load 5a is detected. The first sensor 21 is a distance-limited / reflective photoelectric sensor that detects an obstacle (the protruding load 5a) slightly beyond the end of the load 5 placed on the fork 12. . Therefore, it does not detect the load 5 stored in the load shelf 1 without protruding, and the load 5a protruding on the side of the passage 3 is close to the loaded load 5a. The reflected wave from the end face is received, and the protruding load 5a is detected as an obstacle.

  FIG. 1 is a block diagram of an unmanned forklift 10, and a lift height encoder 22 for calculating a lifting distance of the fork 12, and an opening of the cargo rack 1 along the guide line 4 are laid on the floor surface. A traveling address count sensor 24 for detecting the magnetic bar and recognizing the position of the unmanned forklift 10 and a traveling distance encoder 23 are input to the control unit 30 that controls the entire operation. The control unit 30 controls by a signal from the travel distance encoder 23 how much distance the unmanned forklift 10 travels after the signal from the travel address count sensor 24 is input and stops at the position of the cargo rack 1. is doing. In this travel control, a signal from the control unit 30 controls the travel motor 28 via the travel motor drive unit 27. Further, the control unit 30 controls the lift motor 26 via the lift motor driving unit 25, thereby controlling the lift position of the fork 12 and storing the load 5 in a predetermined load shelf 1. In addition, a notification unit 29 is provided for notifying the worker as a warning when the first sensor 21 detects the protruding load 5a. The second sensor 31 will be described later.

  Next, the control operation of the present invention will be described. As in FIG. 10, as shown in FIG. 2, the load 5 a protrudes and is stored in the load rack 1 (load rack R <b> 13), and is loaded on the load rack R <b> 14 on the upper floor of the load rack R <b> 13 by the unmanned forklift 10. A case where the load 5 is loaded will be described.

  FIG. 2A shows a plan view, and FIG. 2B shows a front view. The load 5 is loaded and the unmanned forklift 10 travels below the load rack R14 to be stored. The unmanned forklift 10 lowers the load 5 while traveling, and controls the traveling motor drive unit 27 until the control unit 30 comes below the shelf R14 by signals from the traveling address count sensor 24 and the traveling distance encoder 23. Then, the unmanned forklift 10 is stopped when it comes below the cargo rack R14.

  This state is the state shown in FIG. 3A, and the control unit 30 controls the lift motor driving unit 25 to raise the fork 12 at that position (see FIG. 3B). The load 5a stored in the lower load rack R13 to be stored protrudes greatly toward the passage 3, so that when the load 5 is lifted as shown in FIG. The load 5a protruding from the first sensor 21 provided on the bracket 11 is detected as an obstacle. When the first sensor 21 detects the load 5a, the control unit 30 that has received the detection signal controls the lift motor driving unit 25 to stop the lift of the load 5 (lift of the fork 12). When the load 5a is not protruding, the first sensor 21 does not detect the load 5a, so that the operation of raising the load 5 and storing the load 5 in the load rack R14 on the upper floor is performed.

  Next, after the first sensor 21 detects the protruding load 5a, the control unit 30 reversely rotates the traveling motor 28 via the traveling motor drive unit 27 to cause the unmanned forklift 10 to move as shown in FIG. One frontage, that is, the cargo rack 1 is moved backward by one. At this position, the loaded load 5 is shifted from the protruding load 5a by one front-to-back direction, so there is no obstacle above the load 5, and the load 5 is raised at that position. It does not come into contact with the protruding load 5a. Then, as shown in FIG. 5, the load 5 is raised to the height position of the load rack R14, and the unmanned forklift 10 is further advanced to the position of the load rack R14 as shown in FIG. 6 (a). Next, as shown in FIG. 6B, the fork 12 is placed in the cargo rack R14, and the cargo 5 is stored in the cargo rack R14, which is a predetermined storage location (see FIG. 6C). In this way, loading of the load 5 on the load rack R14 is completed by the shift operation of the fork 12.

  After completion of the loading, the unmanned forklift 10 is forwarded to a start position that is a standby position (so-called home position). Here, when the first sensor 21 detects the protruding load 5a, the notification unit 29 shown in FIG. 1 warns by sound or display, and the loading 5a on the loading shelf 1 protrudes. The operator is warned of what was happening. Further, as soon as the load 5a protruding from the first sensor 21 is detected, the load 5a may be wirelessly sent to a central control panel (not shown) to notify the worker in real time. An operator who recognizes that the load 5a is protruding by this notification or warning corrects the protruding load 5a by manned work of the manned forklift or the unmanned forklift 10. That is, the load 5a is completely stored so as not to protrude into the load shelf 1.

  As described above, in this embodiment, even when the load 5a protrudes from the load shelf 1, the load 5 is temporarily stopped and moved backward, and then lifted and advanced to the position of the load shelf 1 to be stored. Since the load 5 is stored in the predetermined load shelf 1 by the shift operation, the interference with the protruding load 5a can be prevented, and the error stop until now is automatically continued without interruption. By doing so, the efficiency of the loading operation can be improved. Further, when an overhanging load 5a is detected, an error warning is issued after being sent to the home position of the unmanned forklift 10, thereby reducing manual operation of the unmanned forklift 10 in the warehouse and overall work efficiency. Can be improved.

(Second Embodiment)
By the way, in the previous embodiment, only interference between the load 5a protruding from the load shelf 1 and the load 5 mounted on the fork 12 was considered. However, in this embodiment, the load that protrudes further is considered. This also takes into consideration whether or not 5a and the vehicle body of the unmanned forklift 10 interfere with each other. That is, as shown in FIGS. 6 (a) and 6 (b), when the load 5 protruding beyond the load 5a is raised, the bottom surface of the fork 12 is a large space portion, and therefore the protruding load This is because although interference with 5a itself can be prevented, it may interfere with the mast device of the unmanned forklift 10 and the vehicle body itself.

  That is, as shown in FIGS. 7 and 8, the second sensor 31 is provided at the front portion of the lift bracket 11 of the unmanned forklift 10 via the support member 15. A reflection type photoelectric sensor is used. The detection distance of the second sensor 31 is detected when the load 5a protrudes to the extent that it contacts the vehicle body of the unmanned forklift 10, and when the load 5a protruding by the second sensor 31 is not detected. Even if the unmanned forklift 10 is moved forward, it does not interfere with the load 5a. Therefore, the loading operation is automatically continued without interruption, thereby improving the efficiency of the loading operation. Further, when the load 5a protruding from the second sensor 31 is detected, when the unmanned forklift 10 is moved forward, the unmanned forklift 10 and the load 5a interfere with each other. I try to interrupt.

  Next, the operation of the loading operation when the second sensor 31 is provided in addition to the first sensor 21 will be described. In the case where the load 5a protruding from the first sensor 21 is detected (see FIG. 3C), the operation is the same as in the previous embodiment until the unmanned forklift 10 is once moved backward (see FIG. 4). is there. That is, when the protruding load 5a is detected by the first sensor 21, the unmanned forklift 10 is temporarily retracted by one opening as shown in FIG. 4 and then mounted in the present embodiment as shown in FIG. The load 5 is raised to the level of the protruding load 5a. Next, as shown in FIG. 8, the unmanned forklift 10 is advanced, and the protruding position of the horizontal load 5 a is confirmed by the second sensor 31.

  At this time, when the second sensor 31 detects the protruding load 5a, the unmanned forklift 10 itself comes into contact with the load 5a, so the loading operation is stopped. If the load 5a cannot be detected by the second sensor 31, the unloading forklift 10 is not brought into contact (interference) with the unloading forklift 10 even if the unmanned forklift 10 is moved forward, and the loading operation is continued. As described above, when the load 5a cannot be detected by the second sensor 31, as shown in FIG. 5, the loaded load 5 is raised to the height position where it is stored. The subsequent operation is the same as that of the previous embodiment as shown in FIG. Of course, the warning operation when the first sensor 21 detects the protruding load 5a is similarly performed.

  As described above, in the present embodiment, in addition to the detection of the presence or absence of interference between the load 5 a protruding from the first sensor 21 and the load 5 mounted, the load protruding from the loading shelf 1 by the second sensor 31. Since it is determined whether or not the unmanned forklift 10 interferes with the unmanned forklift 10, even if there is a load 5a protruding from the load shelf 1, the loaded load 5 can be made safer to a predetermined storage location, and It can be reliably transported and stored. Thereby, the efficiency of the loading operation can be further improved.

It is a block diagram of the unmanned forklift in the embodiment of the present invention. (A) (b) is operation | movement explanatory drawing of the loading work in embodiment of this invention. (A)-(c) is operation | movement explanatory drawing of the loading work in embodiment of this invention. It is operation | movement explanatory drawing of the loading work in embodiment of this invention. It is operation | movement explanatory drawing of the loading work in embodiment of this invention. (A)-(c) is operation | movement explanatory drawing of the loading work in embodiment of this invention. It is operation | movement explanatory drawing of the loading work in the 2nd Embodiment of this invention. It is operation | movement explanatory drawing of the loading work in the 2nd Embodiment of this invention. It is a schematic block diagram of a three-dimensional automatic warehouse. It is explanatory drawing which shows the problem in the loading work of a prior art example.

DESCRIPTION OF SYMBOLS 1 Load shelf 5 Load 5a Projecting load 10 Unmanned forklift 21 First sensor 30 Control unit 31 Second sensor

Claims (1)

In an unmanned forklift loading control device for transferring and storing a load mounted on an unmanned forklift to a predetermined loading rack,
A first sensor for detecting whether or not the load protruding from the lower loading rack of the storage destination and the raised load contact when the loaded load is raised;
A second sensor for detecting whether or not the unmanned forklift itself contacts with the protruding load,
When receiving a signal from the first sensor that the loads are in contact with each other, the lift of the load is stopped and the unmanned forklift is moved backward to a position where it does not contact the protruding load. When the unmanned forklift is moved forward after being raised to the height position of the protruding load and the detection signal from the second sensor is not received, the loaded load is raised to the storage height position. A load storage control device for an unmanned forklift characterized by comprising control means for moving the load forward to a storage position and storing the load in a load shelf by a shift operation.

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