JPH0375301B2 - - Google Patents

Description

Detailed Description of the Invention <Industrial Application Field> The present invention provides a loading station that loads workpieces onto a pallet in accordance with a conveyance path, a plurality of machine tools that process workpieces on the pallet, and a processing A plurality of buffer stations are provided for pooling processing pallets to be carried into the machine tool and standby pallets not to be used for processing for the time being, and each machine tool, loading station, and buffer station The present invention relates to a pallet conveying device in a processing system, in which a conveying device for conveying pallets between the pallets is movably provided on the conveying path.

<Prior art> In general, processing systems such as FMS are equipped with multiple buffer stations to place unprocessed workpieces and store pallets until processing starts. A pallet for processing on which a workpiece is attached at a cutting station is conveyed to a buffer station prior to processing. Furthermore, after the processed workpieces are removed, standby pallets that will not be used for the time being are also transported from the loading station to the buffer station and stored therein.

For this reason, conventionally, when a command is given to transport a processing pallet or a standby pallet in a loading station to a buffer station, one of the multiple buffer stations is
A conveying device was provided that sequentially searches for empty buffer stations from the side closest to the machine tool and conveys processing pallets or standby pallets to the searched empty buffer stations.

<Problems to be solved by the invention> However, in such conventional products,
Whether transporting pallets for processing to a buffer station or transporting pallets for standby to a buffer station,
Since empty buffer stations are searched from the side closest to the machine tool, standby pallets are concentrated in the area close to the machine tool, and machining pallets used for machining are conveyed to the area far from the machine tool. There have been times when I have been rejected. As a result, the time required to transport the machining pallets from the buffer station to each machine tool increases, resulting in a problem of lowering the operating efficiency of the system.

<Means for Solving the Problems> FIG. 1 is an overall configuration diagram for clearly demonstrating the present invention. The present invention is a loading station LS
The pallet type setting means A sets whether the pallets in the loading station LS are processing pallets or standby pallets, and the pallet type setting means A sets the pallets in the loading station LS to be processing pallets. In this case, an empty buffer station is searched from a portion of the plurality of buffer stations BS1 to BSn near the machine tools MT1 and MT2, and the pallet type setting means A selects the loading station.
If the pallet in the LS is set as a standby pallet, the multiple buffer stations
An empty station search means B searches for an empty buffer station from a portion of BS1 to BSn far from the machine tools MT1 and MT2, and an empty station search means B searches for an empty buffer station from the loading station LS. The apparatus is equipped with a conveyance control means C for operating a conveyance device D to convey pallets to a buffer station.

<Function> When the pallet type setting means A sets the pallet in the loading station LS as a pallet for processing, the search means B
sequentially searches for empty buffer stations among the buffer stations BS1 to BSn starting from the portions closest to the machine tools MT1 and MT2, and sends the number of the searched buffer station to the transport control means C. As a result, the transport control means C operates the transport device D to transport the processing pallet in the loading station LS to the searched buffer station. On the other hand, when the pallet type setting means A sets the pallet in the loading station LS to be a standby pallet, the search means B selects the pallet from the buffer station BS1.
～Transfer the empty pallet in BSn to machine tool MT1, MT
2 and sends the searched buffer station number to the transport control means C. As a result, the conveyance control means C conveys the standby pallet from the loading station LS to the searched buffer station BS in the same manner as in the previous case. As a result, pallets for machining are conveyed in a concentrated manner to empty buffer stations near the machine tools MT1 and MT2, thereby shortening the machining cycle time.

<Examples> Examples of the present invention will be described below based on the drawings. In FIG. 2, reference numeral 10 indicates a conveyance line along which a pallet P with workpieces is transferred by a conveyance cart 11. Along this conveyance line 10, a plurality of numerically controlled machine tools MT1 and MT2 are arranged at intervals. It is arranged. Each machine tool MT1, MT2 is equipped with a pallet loading/unloading device PC1, PC2, and the pallet P to be processed is carried in from the transport vehicle 11 to the loading entrance of these pallet loading/unloading devices PC1, PC2, and the pallet P to be processed is completed. The pallet P is carried out to the carrier vehicle 11 from the outlet of the pallet carrying in/out devices PC1, PC2.

Also, along the conveyance line 10, pallets P
A loading station LS is installed for loading and unloading workpieces, and a large number of buffer stations BS1 to BS1 are installed to pool pallets P to be processed and standby pallets P' that are not scheduled to be used for the time being. BSn is installed, and these buffer stations include e.g.
Station numbers are numbered from 50 to 65.

Next, the configuration of the control device will be explained.
indicates a computer, and a magnetic disk 21 is connected to this computer 20. NC1,
NC2 is a numerical control device provided corresponding to each of the machine tools MT1 and MT2, and these numerical control devices NC1 and NC2 are connected to the computer 2.
0 via an interface 22, and necessary numerical control data is transferred from the computer 20. Further, the computer 20 is connected to a transfer control device 24 via an interface 23.
are connected, and an operation panel 25 is also connected.

As shown in FIG. 4, within the disk device 21 is a buffer table BT which stores the numbers of each buffer station in association with the numbers of pallets stored in these buffer stations BS1 to BSn. A special code "〓〓" indicating that the pallet is empty is written in the pallet number storage area corresponding to the buffer station to which no pallet is carried.

The transfer control device 24 controls the transfer of pallets P by the transfer vehicle 11 based on commands from the computer 20, and controls the transfer of pallets P and P' between loading station LS and buffer stations BS1 to BSn. In addition to controlling the transfer, the transfer of processing pallets P is also controlled between the buffer stations BS1 to BSn and the machine tools MT1 and MT2.

Next, from the loading station LS to the buffer station in the processing system described above,
The conveyance control of pallets to BS1 to BSn will be explained.

When an operator transports a pallet from loading station LS to buffer stations BS1 to BSn, the operator first presses the push button switch provided on the operation panel 25 as shown in FIG.
Press either SW1 or SW2 to indicate whether the pallet to be transported is a processing pallet P or a standby pallet P'. In this example, pressing switch SW1 indicates that the pallet in loading station LS is a processing pallet, and pressing switch SW2 indicates that the pallet in loading station LS is a standby pallet. It is something to do.
Correspondingly, the computer 20 sets an internal control flag to memorize whether the pallet in the loading station LS is a processing pallet P or a standby pallet P'.

After that, when the operator operates the transport command switch SW3 on the operation panel 25, the computer 20
The transport control process shown in the figure is started. In the first step of this transport control process, depending on the state of the internal flag, it is determined whether the pallet in the loading station LS is a processing pallet P or a standby pallet.
Determine whether it is P′ (40). If the pallet in the loading station LS is determined to be a pallet for processing, the process moves to step (41), and the pallet in the loading station LS is determined to be a standby pallet P'. If so, proceed to step (42). When the process moves to step (41), the start address BTS of the buffer table BT is set to the read counter ROC that specifies the read address of the buffer table BT in the disk device 21, and the process moves to step (42). The final address BTE of the buffer table BT is set in the read counter ROC. In this way, when the initial setting of the read counter ROC is completed, the pallet number is read from the storage area in the buffer table BT specified by the read counter ROC (43), and this read pallet number is coded as a special code "〓〓". , it is determined whether the buffer station corresponding to the area number specified by the read counter ROC is empty (45). If it is empty, the process moves to step (46), but if it is not empty, the process moves to step (47), where the contents of the read counter ROC are updated. That is, when the pallet in loading station LS is a processing pallet, 1 is added to the contents of the read counter ROC (48), and when the pallet in loading station LS is a standby pallet P', subtracts 1 from the contents of the read counter ROC (49). After the read counter has been updated in this way, the process returns to step (43) and the above operations are repeated.

This allows loading station LS
If the pallet inside is a machining pallet P, the empty buffer station is machine tool MT1,
50th buffer station BS1 near MT2
Loading station
If the pallets in LS are standby pallets, empty buffer stations are sequentially searched starting with buffer station BSn number 65, which is far from machine tools MT1 and MT2. When an empty buffer station is searched, the process moves from step (45) to step (46), and the number of the empty buffer station is output to the transport control device. That is, when it is determined that the palette is empty because the pallet number read from the area specified by the read counter ROC is a special code, the buffer station number is read from the area specified by the read counter ROC. , and outputs this to the transport control device 24.

In response to this, the transport control device 24 loads the pallet onto the transport vehicle 11 from the loading station LS, moves the transport vehicle 11 to a position corresponding to the empty buffer station, and then loads the pallet onto the transport vehicle 11. Empty pallets are carried into the buffer station, but if there is a processing pallet P in the loading station LS as described above, the empty buffer station is loaded into the machine tool.
Buff station BS close to MT1 and MT2
1, and if the pallet in loading station LS is standby pallet P', empty buffer stations are searched from buffer station BSn on the far side from machine tools MT1 and MT2. Palette P for processing
are transported in a concentrated manner near the machine tools MT1 and MT2, and the standby pallet P′
1. It will be transported to a part far from MT2.

Therefore, buffer station BS1~1
When processing the workpiece placed on the processing pallet P in BSn, machine tools MT1 and MT2 are used.
The time taken to transport the material to the machine is shortened, and processing efficiency can be improved.

FIG. 5 shows a second embodiment of the present invention, which differs from the previous embodiment in that a buffer table BT is added to the read counter ROC in step (42).
By initializing the readout address BTC approximately in the middle of The point is that the read counter ROC is updated by adding 1 to the read counter ROC (48) whether it is the standby pallet P or the standby pallet P'.

As a result, if the pallet in loading station LS is processing pallet P, buffer station BS1 with station number 50 will be loaded.
If the pallet in the loading station LS is the standby pallet P', an empty buffer station will be searched from buffer station No. 58, which is located approximately in the middle. Become. In this case, as in the above embodiment, the processing pallet P is transported to a position close to the machine tools MT1 and MT2, and the standby pallet P' is transported to a position far from the machine tools MT1 and MT2. , the time for conveying the processing pallet P during processing is shortened, and processing efficiency can be improved.

<Effects of the Invention> As described above, in the present invention, when the pallet in the loading station is a processing pallet, the pallet is transported to the part of the plurality of buffer stations near the machine tool, and the loading station is When the pallets at the station are standby pallets, the pallets are transported to a part of the multiple buffer stations far from the machine tool, so the pallets for processing are concentrated in the part close to the machine tool. This has the advantage that processing efficiency can be improved by reducing the transport distance of processing pallets during processing and shortening the transport time for transporting processing pallets in the buffer station to the machine tool.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram for clearly demonstrating the present invention.
2 to 5 show a first embodiment of the present invention. FIG. 2 is a diagram showing the overall configuration of the processing system along with a control circuit, and FIG. 3 is a diagram showing the operation of the computer 20 in FIG. 2. FIG. 4 is a flowchart showing the buffer table BT stored in the disk device of FIG. 2, and FIG. 5 is a flowchart showing a second embodiment of the present invention. 10... Conveyance line, 11... Conveyance truck, 20
...Computer, 24...Transfer control device, 25
...Operation panel, MT1, MT2...Machine tool, LS...
...Loading station, BS1~BSn...
Buffer station, P...processing pallet,
P′...Standby palette.

Claims (1)

[Scope of Claims] 1. A loading station that loads workpieces onto pallets in correspondence with the transport route, a plurality of machine tools that process the workpieces on the pallets that have been carried in, and a loading station that carries the workpieces to the machine tools for processing. A plurality of buffer stations are provided to pool pallets for processing to be processed and standby pallets not to be used for processing for the time being, and the pallets are transported between each of the machine tools, the loading station, and the buffer station. In a processing system in which a device is movably provided on the conveyance path, a pallet type setting means for setting whether a pallet in the loading station is a processing pallet or a standby pallet, and the pallet type setting means If the pallet in the loading station is set as a machining pallet, search for an empty buffer station from the part of the plurality of buffer stations near the machine tool, and set the pallet type setting. an empty station search means for searching for an empty buffer station from a portion of the plurality of buffer stations far from the machine tool when the pallet in the loading station is set as a standby pallet; a pallet processing system, comprising: a transport control means for operating the transport device to transport the pallet from the loading station to the empty buffer station searched by the empty station search means; Conveyance device. 2. The plurality of buffer stations have station numbers that sequentially change from the side closest to the machine tool to the side farthest from the machine tool, and the empty station search means determines whether the selected buffer station is empty or not. If the pallet of the loading station is set as a machining pallet by the discriminating means and the pallet type setting means, the buffer closest to the machine tool among the plurality of buffer stations is selected. The buffer station is selected in numerical order from the stations and the discrimination means is activated, and if the pallet in the loading station is set as a standby pallet by the pallet type setting means, the plurality of buffer stations are selected in numerical order. and control means for selecting the buffer stations in the pallet in an order opposite to the numerical order from the buffer station on the side farthest from the machine tool and operating the discrimination means. A pallet conveying device in a processing system according to claim 1. 3. The plurality of buffer stations are divided into a first group closer to the machine tool and a second group farther from the machine tool, and the empty station search means detects whether each buffer station is empty. determination means for determining whether or not there is a buffer station in the first group; and when the pallet type setting means sets that the pallet of the loading station is a processing pallet When the discriminating means is enabled and the pallet of the loading station is set as a standby pallet by the pallet type setting means, the discriminating means is applied to buffer stations in the second group. A pallet conveying device in a processing system according to claim 1, characterized in that it is constituted by a control means for operating the pallet conveying device.