JP3083036B2 - Automatic lift control system for forklift trucks - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic lifting and stopping control device for a forklift truck in a loading / unloading operation of a load on a rack.

[0002]

2. Description of the Related Art Conventionally, a shelf number of a loading and unloading rack, that is, stop position information of a fork corresponding to each location is stored in a memory in advance, and when loading or unloading goods from or to a rack, the stop is performed. There is an automatic lift stop control device of a forklift truck that lifts and stops a fork based on position information. In this type of automatic lifting and stopping controller, due to rack mounting accuracy and road surface accuracy,
It is necessary to finely adjust the lifting stop position of the fork for each rack. An optical sensor is provided at the tip of the fork as a pallet gap detector, and the pallet gap is detected by a laser or infrared ray emitted from this optical sensor. In some cases, the lift stop position of the fork is finely adjusted.

[0003]

However, such a pallet gap detector as described above is expensive, leading to an increase in the cost of the apparatus, and sometimes malfunctions due to dirt or damage to the pallet. The present invention solves the above-described problem, and finely adjusts a fork stop position according to each position error of a rack without using an expensive sensor, and accurately stops the fork at an appropriate position. It is an object of the present invention to provide an automatic lifting and stopping control device for a forklift vehicle capable of reducing the cost of the device.

[0004]

According to a first aspect of the present invention, a fork is lifted and stopped on the basis of fork stop position information corresponding to each of the rack locations stored in advance. Reading means for reading position error information of each rack attached to the forklift truck and attached to each of the racks in the forklift truck automatic lifting and stopping controller for loading and unloading the luggage to and from the rack; An on-board terminal mounted on the forklift vehicle and correcting stop position information of the fork based on information read by the reading means, and the on-board terminal corrected based on the stop position information corrected by the on-board terminal. And a fork drive control means for controlling a lift stop position of the fork.

According to a second aspect of the present invention, there is provided a forklift for lifting and stopping a fork based on stop position information of a fork corresponding to each of the locations of a rack stored in advance, and for loading and unloading goods to and from the rack. In a vehicle automatic lifting and stopping control device, position error information of each rack is stored, and an inventory management machine for transmitting data including an instruction for loading / unloading of goods to / from the rack and the position error information to the forklift vehicle. A location data reading unit mounted on the forklift truck and reading location data of each rack attached to each location of the rack; a location data reading unit mounted on the forklift truck and read by the location data reading unit. Compare the location data with the data sent from the inventory management machine, If so, the on-board terminal that obtains the stop position information corrected based on the position error information transmitted from the inventory management device, and the stop position information obtained by the on-board terminal Fork drive control means for controlling the stop position of the fork based on the fork drive control means.

[0006]

According to the above construction, when the position error information of each rack attached to each rack location is read by the reading means, the onboard terminal reads the information based on the information. The fork stop position information corresponding to each of the rack locations stored in advance is corrected, and the fork drive control means controls the fork lifting stop position based on the corrected information. As a result, the stop position of the fork is finely adjusted in accordance with each position error of the rack, the fork can be stopped at an appropriate position with respect to each rack, and the cargo can be smoothly loaded and unloaded.

Further, according to the configuration of the second aspect, the inventory management machine transmits the data including the positional error information of each stored rack to the forklift vehicle together with the instruction for loading / unloading of the rack with respect to the rack. The on-board terminal mounted on the forklift vehicle receives the data, compares the received data with the location data read by the location data reading means, and compares the received data with the location data. If they match, stop position information with an error corrected based on the received data is obtained, and the fork drive control means controls the fork lift stop position based on the information. Thereby, the same operation and effect as described above can be obtained.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an entry / exit work management system. The office is provided with an inventory management machine 1 for registering and managing luggage entry / exit data, and a printer 2 for outputting luggage management information and error messages. The warehouse is provided with a rack 4 on which the load 3 is loaded in units of pallets 3a, and a forklift truck 5 moves around in the warehouse to carry the load 3, and performs loading and unloading operations on the rack 4. The forklift vehicle 5 is equipped with an on-board terminal 10 and a barcode scanner 11. A bar code 12 is attached to the rack 4 for each location. This barcode 1
2 stores the location (shelf number) data of the rack 4 and the position error data of each rack. By reading these data with a bar code scanner 11 mounted on the forklift truck 5, location management, Fork drive control is performed. The details of the fork drive control will be described later.

The inventory management machine 1 in the office is connected to the wireless terminal 6 in the warehouse by a line, and the wireless terminal 6 is connected to the antenna 9 via the adjuster 7 and the distributor 8 by a line. The inventory control device 1 and the on-board terminal device 10 of the forklift truck 5 wirelessly communicate entry and exit data via the antenna 9.

FIG. 2 is an external view of an on-board terminal 10 mounted on a forklift vehicle. The on-board terminal 10 has an on-board antenna 13 for wirelessly communicating with the antenna 9.
And a display screen 14 for displaying entry / exit instruction data, position error data of each rack 4 and the like, and a keyboard 15 for inputting data to the on-board terminal 10. Note that the medium for data exchange between the inventory management machine 1 and the on-board terminal 10 is not limited to the above-described wireless, and an IC card or the like may be used. In that case, during the loading / unloading operation, the IC card is mounted on the on-board terminal 10 and the loading / unloading data is written into the IC card as needed.
The IC card may be passed to the inventory management machine 1 after the entry / exit operation.

FIG. 3 is a block diagram showing the construction of the automatic lifting and stopping control device for a forklift truck according to the present invention in the above-mentioned storage and retrieval work management system. The automatic lifting and stopping control device includes an inventory management device 1, an on-board terminal device 10, a barcode scanner 11, and a fork drive control device 16. When the push button 18 is pressed, the fork drive control device 16 controls the drive of the fork drive motor 17 based on data from the on-board terminal 10. In the memory 10a of the on-board terminal 10, fork stop position data corresponding to the number of storage stages of the rack 4 is stored in advance, and height error and horizontal error data of each rack based on the stop position data are stored. (Position error data) is stored in a barcode 12 attached to each location of the rack 4.

FIG. 4 is a flow chart showing the automatic lifting stop control operation. When the in-vehicle terminal 10 receives the loading / unloading work instruction information from the inventory management machine 1 (S1), the instruction information is displayed on the display screen 14 of the on-vehicle terminal 10. As shown in FIG. 2, the display screen 14 displays a product number 21 of the package, a date 22 when the product was moved in and out, a quantity 23 of the package, and a location number 24 of the rack 4. The operator moves the forklift truck 5 to a predetermined rack 4 in accordance with the contents displayed on the display screen 14.

Next, when the barcode 12 attached to the rack 4 is read by the barcode scanner 11 (S
2) Check whether the read location data of the rack 4 matches the location number specified by the inventory management machine 1 and display the read position error data (height error and horizontal error) 25 of the rack 4 It is displayed on the screen 14 (see FIG. 2). The fork stop position data is corrected by performing an arithmetic process based on the position error data and the stop position data (lift height reference value) stored in the memory 10a in advance (S3). Next, when the push button 18 is pressed down (YES in S4), the fork drive control device 16 receives the corrected stop position data, and drives the motor 17 based on this to raise the fork to a predetermined position. (S5).

As described above, the position error data of each rack 4 stored in the barcode 12 is read, and the on-board terminal 10 corrects the stop position data stored in the memory 10a in advance based on the data. By doing so, each rack 4
Each time the fork can be stopped accurately at an appropriate position, it is not necessary to mount an expensive pallet gap detector on a forklift truck as in the related art. In addition, only the fork stop position data (lift reference value) corresponding to the number of storage stages of the rack 4 need be stored in the memory 10a of the on-board terminal 10, so that the memory capacity of the on-board terminal 10 Does not need to be increased, and the cost of the apparatus can be reduced.

Next, a second embodiment of the present invention will be described. In the first embodiment, the position error data in each rack 4 is stored in the barcode 12 provided for each location of the rack 4, whereas in the second embodiment, the position error data is stored in the inventory management machine 1. In the memory. In this case, only the location data of the rack 4 needs to be stored in the barcode 12. FIG. 5 is a flowchart showing the automatic lifting stop control operation according to the second embodiment. When the on-board terminal 10 receives the loading / unloading work instruction information and the position error data (height error and horizontal error) of the rack 4 from the inventory management machine 1 (S11), the on-board terminal 10 sends the instruction information and the position error data on the vehicle. It is displayed on the display screen 14 of the terminal device 10.
The display contents are the same as in the first embodiment. The operator moves the forklift truck 5 to a predetermined rack 4 in accordance with the contents displayed on the display screen 14.

Next, when the bar code scanner 11 reads the bar code 12 attached to the rack 4 (S).
12) It is checked whether the read location data of the rack 4 matches the location number specified by the inventory management machine 1, and the position error data received above is
The fork stop position data is corrected by performing arithmetic processing based on stop position data (lift height reference value) stored in the memory 10a in advance (S13). It is raised to a predetermined position (S14 to S15).

As described above, the error data of each rack 4 is stored in the memory of the inventory management device 1 having a large memory capacity, and the data is transmitted from the inventory management device 1 to the on-vehicle terminal device 10 during the loading / unloading operation. Then, the fork is accurately stopped at an appropriate position for each rack 4 by correcting the stop position data stored in the memory 10a in advance on the basis of the received data by the on-board terminal 10. Can be
Further, since only the stop position data of the fork corresponding to the number of storage stages of the rack 4 need be stored in the memory 10a of the on-board terminal device 10, the same effect as in the first embodiment can be obtained.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the location data of each rack 4 is stored in a barcode 12, and the barcode 12 is read at the time of loading / unloading work, so that the location number is checked. You may. In this case, each rack 4
Need not be displayed with the barcode 12.

In the second embodiment, fork stop position data (reference value) corresponding to the number of storage stages of the rack 4
Is stored in the memory 10 a of the on-board terminal 10, and the stop position data in each rack 4 is corrected by the on-board terminal 10. This stop position data is also stored in the memory of the inventory management device 1. Alternatively, the stop position data may be corrected by the inventory management device 1 and the corrected data may be sent to the on-board terminal 10. In this case, the memory capacity of the on-board terminal 10 may be smaller than those of the first and second embodiments, and the cost of the device can be reduced.

[0020]

As described above, according to the first aspect of the present invention,
Even without using an expensive sensor such as a pallet clearance detector,
By reading the position error information of each rack, such as a bar code attached to each rack location, and correcting the fork stop position information stored in the memory in advance with the onboard terminal based on the information. , The fork can be accurately stopped at an appropriate position for each rack,
Moreover, only the fork stop position information corresponding to the number of rack storage stages need be stored in the memory of the on-board terminal, so that it is not necessary to increase the memory capacity of the on-board terminal, and the cost of the device is reduced. Can be reduced.

According to the second aspect of the present invention, even if an expensive sensor such as a pallet gap detector is not used, the position error information of each rack is stored in an inventory management machine having a large memory capacity, and the information is input. At the time of unloading work, the data including the position error information is transmitted from the inventory management device to the on-board terminal, so that the on-board terminal obtains the stop position information with the error corrected, and the fork is set at the proper position for each rack. And it is not necessary to store the position error information of each rack in the memory of the on-board terminal, so that it is not necessary to increase the memory capacity of the on-board terminal, and the cost of the apparatus is reduced. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a storage and retrieval work management system including an automatic lifting and stopping control device for a forklift truck according to a first embodiment of the present invention.

FIG. 2 is an external view of an on-board terminal mounted on a forklift vehicle in the control device.

FIG. 3 is a block diagram showing a configuration of the control device.

FIG. 4 is a flowchart showing an operation of the control device.

FIG. 5 is a flowchart showing an operation of an automatic lifting and stopping control device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inventory control machine 4 Rack 5 Forklift truck 10 Onboard terminal 10a Memory 11 Barcode scanner 12 Barcode 16 Fork drive control device

Claims (2)

(57) [Claims] 1. An automatic lifting and stopping control of a forklift vehicle that lifts and stops a fork based on stop position information of a fork corresponding to each of the locations of a rack stored in advance and loads and unloads cargo from and to the rack. A reading unit provided on the forklift truck for reading positional error information of each rack attached to each of the rack locations; and a reading unit mounted on the forklift truck and based on the information read by the reading unit. An on-board terminal for correcting the stop position information of the fork; and a fork drive control means for controlling the lift stop position of the fork based on the stop position information corrected by the on-board terminal. An automatic lifting and stopping control device for a forklift truck. 2. An automatic lifting and stopping control of a forklift vehicle that lifts and stops a fork based on fork stop position information corresponding to each of the locations of a rack that is stored in advance, and loads and unloads cargo from and to the rack. In the apparatus, the position error information of each rack is stored, and an inventory management machine that transmits to the forklift vehicle data including a loading / unloading instruction for the rack and the position error information, and mounted on the forklift vehicle. And the location of each rack
Location data for each rack
And location data reading means for reading the data, is mounted on the forklift vehicle, the location de
Data read by the data reading means and the
Compare with the data sent from the inventory management machine,
If there is, the position sent from the inventory control machine
Obtain stop position information with the error corrected based on the error information
That the on-board terminal, automatic fork height stop of a forklift vehicle, characterized in that it comprises a fork drive control means for controlling the stop position of the fork based on the obtained stop position information by the onboard terminal Control device.