JP2821164B2 - Transfer control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention relates to a transfer control device that is effective when processing a workpiece using a plurality of processing stations, a plurality of shelf stations, and a transfer device.

[Prior art]

Conventionally, in FMS (flexible manufacturing system), a plurality of buffer stations, which temporarily store a workpiece before processing, a workpiece in the middle of processing, or a completed workpiece, are used. Shelf stations are used. For example, a serial number is assigned to each of the plurality of shelf stations from a side closer to a processing station for processing a workpiece. By searching in order, the shelf station that takes the shortest transfer time is used. In a shelf station using a three-dimensional stocker, the shelf may be a fixed address (an address associated with the type of workpiece, etc.) without free use.

[Problems to be solved by the invention]

In the case where there are a plurality of processing stations and a plurality of shelf stations are planar, even if a plurality of shelf stations are searched in ascending order, the shelf station number position is not necessarily changed from the processing station based on the work order of the workpiece to the shelf station. It cannot be said that the transfer time is the shortest to reach the processing station via. Further, in the case where the plurality of shelf stations are not flat shelf stations, but are shelf stations using a three-dimensional stocker, etc., the shelf station numbers cannot be simply arranged side by side in the conventional search system in ascending order. It is not possible to find a shelf station number position where the transfer time is shortest from the processing station based on the processing order to the processing station via the shelf station. Also, when a fixed address is adopted in the three-dimensional stocker, even if the shelf station with the shortest transport time is available from the processing station based on the processing order of the workpiece to the processing station via the shelf station, even if the shelf station is empty. Since the determined shelf station is used, the transport time is wasted. The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide each transport path using a shelf station from a processing station to a processing station via a shelf station. The use priority of shelf stations is assigned in the order of the shortest transfer time, and waste of transfer time is reduced by using empty shelf stations based on the use priority for each transfer path based on the processing order of the workpiece. An object of the present invention is to provide a transfer control device capable of minimizing the transfer.

[Means for Solving the Problems]

The configuration of the invention for solving the above-mentioned problem uses a plurality of processing stations for processing a workpiece, a plurality of shelf stations, which are buffer stations for temporarily storing the workpiece, and a transfer device, and transfers the workpiece. In a transfer control device for carrying in and out for processing at a plurality of processing stations based on a preset processing order, a transfer control apparatus that performs one of a plurality of processing stations from a first processing station to a second processing station. 2 Before reaching the processing station,
In order to determine the order of the transport time in each of the plurality of shelf stations with respect to the length of the transport time, assuming all the transport routes that pass through each of the plurality of shelf stations. Station information storage means for storing in advance the information associated with each of the above-mentioned shelf stations, and loading the workpiece, which has been processed in the first processing station, into one of the shelf stations so as to wait for processing in the second station. If so, based on the information stored in the shelf station information storage means,
Shelf station searching means for finding a shelf station having the shortest transfer time among shelf stations not in use at that time, and a transfer device for loading a workpiece to the shelf station determined by the shelf station searching means And a shelf station instructing means for instructing the shelf station.

[Action]

The shelf station information storage means stores information for determining the order of the length of transport time from the first processing station to the second processing station via each shelf station, corresponding to each shelf station. Then, when placing the workpiece on one of the shelf stations in order to wait for the workpiece that has been processed in the first processing station to be processed in the second processing station, the information is stored in accordance with the information stored in the shelf station information storage means. The shelf station searching means finds a shelf station with the shortest transport time among shelf stations not used at that time. Next, the shelf station instructing means instructs the transfer device to carry in the workpiece to the shelf station determined by the shelf station searching means. Since the position of the shelf station to be used is determined in this way, the transfer time when using the shelf station based on the processing order of the workpiece with respect to the arrangement of the plurality of processing stations and the shelf stations can be shortened.

【Example】

Hereinafter, the present invention will be described based on specific examples. FIG. 1 is a configuration diagram showing the overall configuration of the transport control device of the present invention. As a plurality of processing stations, a processing station 1 as a horizontal machining center and a processing station 2 as a vertical machining center are installed side by side. Opposite to the two processing stations 1 and 2, a shelf station 3 which is a three-dimensional stocker as a buffer station and a stocker crane 4 as a transfer device between the processing stations 1 and 2 and the shelf station 3 are arranged. A crane 41 is placed on the rail of the crane 4. Two loading stations 51 and 52 are arranged at one end of the stacker crane 4 and adjacent to and parallel to the stacker crane 4. The shelf station 3 is divided into three floors as shown in the front view in the direction of the arrow, and each of the shelf station positions has a shelf station number of 101 to 121.
Is attached. Reference numeral 10 denotes a computer of the transfer control device. The computer 10 mainly includes a CPU 11, a ROM 12 storing a control program, and a RAM 13 storing input data and the like. R
The AM 13 is provided with a shelf station storage area 131 for storing shelf station use priority information and a transport path storage area 132 for storing a transport path for each type of workpiece. CPU 11 is a processing station via interface 16
It is connected to the numerical control devices 1 and 2 and receives a work loading / unloading request signal at the processing stations 1 and 2.
Further, a work loading / unloading request signal from the loading stations 51 and 52 is input to the CPU 11 via the interface 16. The CPU 11 is connected to the control panel of the stacker crane 4 via the interface 17, and outputs a movement position command signal to the crane 41 or inputs a determination signal of a type of a work placed on the crane 41. Further, the CPU 11 is connected to a keyboard 21 for inputting data via an interface 18 and a CRT display device 22 for displaying data. The transport path of the workpiece in the above arrangement configuration includes a path from the loading station 51 or 52 to the processing station 1 or 2 via the shelf station 3,
Further, a path from the processing station 1 to the processing station 2 via the shelf station 3, a path directly loaded from the loading station 51 or 52 to the processing station 1 or 2, and a path directly from the processing station 1 to the processing station 2. There are routes to be carried in. Here, in the transport route that does not use the shelf station, the transport time is constant due to the traveling performance of the stacker crane 4 and the like. Therefore, first, among the above-described transfer paths in the design stage as pre-processing, the transfer path using the shelf station, for example, from the processing station 1 to the shelf station 3
The information for determining the order from the shelf station with the shortest transfer time to the processing station 2 via the above is obtained as follows. 2A, the distance from the processing station 1 to each shelf station position of the shelf station 3 and the distance of the path (not shown) from each shelf position of the shelf station 3 to the processing station 2 are obtained. . Next, the required transport time in the above route is obtained for each shelf station position. Here, the crane 41 of the stacker crane 4 is shown in FIG. 2 (b) from the processing station 1 to each shelf station position of the shelf station 3 due to inherent speed characteristics including acceleration and deceleration characteristics in the traveling direction and the vertical direction. A characteristic diagram for the required time is obtained. Further, a characteristic diagram (not shown) relating to the required time from each shelf position of the shelf station 3 to the processing station 2 is obtained. 2 above
The transport time from the processing station 1 to the processing station 2 via the shelf station 3 is obtained by combining the two characteristic diagrams. As described above, for each shelf station position, the transport time from the processing station 1 to the processing station 2 via the shelf station 3 is obtained as shown in FIG. 3 (a). Then, in the transport path from the processing station 1 to the processing station 2 via the shelf station 3 in FIG. 3A, the shelf station Nos. Are sorted in ascending order by the transport time, and FIG. obtain. In this manner, the shelf station numbers stored in the RAM 13 for realizing the shelf station information storage means of the present transport control device are obtained by arranging the shelf station numbers in ascending order of transport time for each transport route as shelf station use priority information. The transport path information in the machining process for each type of workpiece as shown in FIG. 4 is stored in the transport path storage area 132 of the RAM 13 in advance in the area 131. Next, the CPU 1 of the computer 10 constituting the apparatus of the embodiment
The processing procedure 1 will be described with reference to the flowchart of FIG. In step 100, a hardware monitoring process is executed to read a work loading / unloading request signal from the loading stations 51, 52 or the processing stations 1, 2. Next, the process proceeds to step 102, where it is determined whether or not the carry-in / out request signal read in step 100 has a carry-out request.
If there is an unloading request in step 102, the determination is YES, and the routine proceeds to step 104. In step 104, a crane control process is executed, and the crane 41 on the stacker crane 4 is moved to the unloading request position where the unloading request signal is output, and the workpiece is placed on the crane 41. Then, the process proceeds to step 106, where the type of the workpiece placed on the crane 41 is checked. This check is necessary when there are a plurality of types of workpieces, the processing steps are different, and the processing paths are different, and the check is performed in the transfer path storage area 132 in the RAM 13 as shown in FIG. From a table stored in advance, the transport path in the processing step can be known. As the checking method described above, for example, a mark indicating the type or the like may be attached to the workpiece, and the mark may be determined by a reading device (not shown) provided on the crane 41. Next, the process proceeds to step 108, where it is determined whether or not there is a workpiece of the same type as the workpiece on the crane 41 in the shelf station 3 at that time based on the type check of the workpiece in step 106. Step 108 when there is a workpiece
Is YES, the process proceeds to step 110, and, for example, a table of shelf station use priority information shown in FIG. 3 (b) is selected based on the transport path in the machining process for each type of workpiece. Next, the process proceeds to step 112, in which the table pointer, which is ranked from the highest priority in the table of the selected shelf station use priority information, is set to the initial value of 1, and the process proceeds to step 114. In step 114 for achieving the shelf station searching means, it is determined whether or not the shelf station designated by the table pointer 1 initialized in step 112 is free. Here, if the shelf station position specified by the table pointer 1 is not empty, since (*) is present as a flag at the shelf station position specified by the table pointer 1, the process proceeds to step 116 and the table pointer is moved to the next address. After correspondingly proceeding by 1, the process returns to step 114, and steps 114 to 116 are repeated. In this way, it is determined whether or not the shelf station positions are vacant in the order of the table pointers. At step 114, there is no flag at the shelf station position designated by the table pointer (for example, the table pointer 3 in FIG. 3B). Since the shelf station position is the shelf station No. 105) and the shelf station position is empty, the determination is YES, and the routine goes to step 118. In step 118 for achieving the shelf station command means, a work transfer command determination process is executed, and the crane 41 of the stacker crane 4 as a transfer device is moved to the shelf station position determined to be vacant in step 114, and the crane 41 is moved.
Carry in the above work. Next, the process proceeds to step 120, and the flag of the position of the shelf station No. into which the workpiece has been carried in step 118 is turned ON (*). Then, the process proceeds to step 122, where the flag O is set to the shelf station No. position where the flag was set to ON (*) in step 120
The N time is stored, and the process returns to step 100. Incidentally, in the above-mentioned step 108, the shelf station 3
If there is no workpiece of the same type as that on the crane 41, the determination is NO, and the process proceeds to step 124, where the hardware monitoring process is executed, and the processing is performed based on the machining process of the type of workpiece on the crane 41. A carry-in request signal for the workpiece is output, and it is determined whether there is a carry-in request. Step 12 if there is no import request
The determination of 4 is NO, and the process proceeds to step 110 described above. Then, in step 124, the determination that there is a carry-in request signal is Y
It becomes ES and moves to step 126. In step 124,
The work transfer command determination process is executed, and the crane 41 is moved to the carry-in request position where the carry-in request signal is output in step 124 without passing through the shelf station 3.
The upper workpiece is loaded, and the process returns to step 100. Further, in step 102 described above, if there is no transport request signal, the determination is NO, and the process proceeds to step 128.
It is determined whether there is a carry-in request in the work-in / out request signal read in step 100. If there is a carry-in request in step 128, the determination is YES, and the routine goes to step 130. In step 130, it is determined whether or not there is a workpiece having a transfer route to be carried into the carry-in request position in step 128 in the shelf station 3. The work to be carried in step 130 is shelf station 3
Is YES, the process proceeds to step 132, and, for example, based on the transport path for each type of workpiece, FIG. 3 (b)
Select the shelf station use priority information table indicated by. Next, the process proceeds to step 134, where a crane control process is executed, and the flag is ON (*) on the table of the shelf step use priority information selected in step 132, and the shelf station No. whose flag ON time is the earliest is set. The crane is moved to a position (for example, shelf station No. 102 which is the shelf station position of the table pointer 4 in FIG. 3 (b)).
Move 41 to place the workpiece. This is because, assuming that the workpiece is processed according to the first-in first-out principle, the workpiece having the earliest processing end time in the previous process must be preferentially conveyed to the next processing step. Then, the process proceeds to step 136, where the flag of the shelf station No. position where the work was unloaded in step 134 is turned off and the flag ON time is deleted. Next, the process proceeds to step 138 to execute a work transfer command determination process, move the crane 41 to the carry-in request position, carry in the work on the crane 41, and return to step 100. It should be noted that in the above-described step 128, the determination that there is no carry-in request is NO, and the process returns to step 100. In step 130 described above, the determination that the workpiece to be carried in is not in the shelf station 3 is NO, and
Return to 100. Further, as auxiliary processing, screen control (monitor display) is performed on the state of a work loading / unloading request of the processing stations 1 and 2 or the loading stations 51 and 52, the transfer path of the work on the crane 41, and the like. Is displayed in. In the above-mentioned program, the type of the workpiece is checked on the crane 41. However, when the workpiece is placed on the pallet and transported, the work corresponding to the loaded workpiece is performed. Then, a mark for detection is attached to the pallet in advance, and the mark is determined by a reading device (not shown) of the crane 41, so that the transfer control can be similarly performed by the present transfer control device. Also, when using a pallet and it is necessary to place a workless pallet that is not used for the time being on the shelf station,
By searching for the table pointer of the above-mentioned shelf station use priority information in ascending order, that is, by evacuating unused ones farther away, a frequently used shelf station position that can shorten the transport time in normal processing. It can be used, which is a preferable transport control device when a pallet is used. In this way, it is possible to use available shelf station positions in ascending order of transport time for each transport path based on the processing order of the workpiece, and as a result, it is possible to reduce the transport time of the entire system. .

【The invention's effect】

According to the present invention, in order to determine all the transport paths that pass through each of a plurality of shelf stations from the first processing station to the second processing station, and determine the order of the transport time in these transport paths. Is stored in advance, and when a workpiece that has been processed at the first processing station is carried into one of the shelf stations so as to wait for the processing at the second station, the information is ranked based on the information on the order. A shelf station with the shortest transport time is found among shelf stations that are not used at that time, and a workpiece is loaded into the shelf station. Therefore, among the empty shelf stations, the empty positions are used in ascending order of the transport time for each transport route, so that the transport time for loading and unloading the workpiece for processing the workpiece at the processing station is used. It can be shortened as a whole.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing the overall configuration of a transport control device according to a specific embodiment of the present invention. FIG. 2A is a characteristic diagram showing a transport path from a processing station to a shelf station according to the embodiment. FIG. 2 (b) is a characteristic diagram showing the transport time with respect to FIG. 2 (a). FIG. 3A is an explanatory diagram showing transport times in the order of shelf station numbers based on the transport route according to the embodiment. FIG. 3B is an explanatory diagram showing a shelf station use priority information table in which the shelf station numbers in FIG. 3A are sorted in ascending order based on the transport time. FIG. 4 is an explanatory view showing the types of workpieces according to the embodiment and the transport paths in the processing steps. FIG. 5 is a flowchart showing a processing procedure of a CPU used in the apparatus of the embodiment. 1 ... processing station (horizontal machining center) 2 ... processing station (vertical machining center) 3 ... shelf station 4 ... stacker crane 10 ... computer, 11 ... CPU 16, 17, 18 ... interface 21 ... Keyboard, 22 CRT display 41 Cranes 51, 52 Loading station

Continuation of the front page (56) References JP-A-61-44565 (JP, A) JP-A-59-116306 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65G 1 / 00-1/20 B23Q 41 / 02,41 / 08

Claims (1)

(57) [Claims] 1. A plurality of processing stations for processing a workpiece, a plurality of shelf stations serving as buffer stations for temporarily storing the workpiece, and a transfer device,
In a transfer control device for carrying in and out for processing the workpiece at the plurality of processing stations based on a preset processing order, a transfer control apparatus may be configured to perform one of the plurality of processing stations from a first processing station. Before reaching the second processing station, which is one of the plurality of shelf stations,
Assuming that all of the transport routes passing through each of the plurality of shelf stations are assumed for the transport route that passes through one of the plurality of shelf stations, information for determining the order of length of transport time in these transport routes is stored in each of the shelf stations. A shelf station information storage means for storing in advance the work in the second processing station;
When carrying into one of the shelf stations in order to wait for the processing of the station, based on the information stored in the shelf station information storage means, among the shelf stations that are not used at that time, Shelf station searching means for finding a shelf station with the shortest transfer time; and shelf station command means for instructing the transfer device to load the workpiece into the shelf station determined by the shelf station searching means. A transfer control device comprising: