JPH0453657A - Simulation method for multiple kind mixed production line - Google Patents

Abstract

PURPOSE:To set an appropriate planned production quantity by performing the simulation of the motions of a product transfer line and part feeding line based on input data. CONSTITUTION:The input of data with respect to a product transfer line and part feeding line is performed. In succession the inputs of the planned production of each product, the input order into the production line of each product, the work carry-in and out times on each stage of a product transfer line and a part feeding time into each stage are performed. Also, the load quantity for each stage of each product is operated and input. Then, the simulation is performed according to the production plan and the work starting time and work completion time at each stage of each product are found. In the case of the work completion time of a work flowed first and the work starting time of the work to be flowed next is overlapped, the correction of shifting the work starting time of the work to be flowed next by the overlapped time is applied.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a product transport line that consistently performs operations from loading a workpiece to unloading a completed product, and The present invention relates to a simulation method for a multi-product mixed production line consisting of a plurality of component supply lines that supply components for assembly to workpieces.

(Prior art) In a multi-product mixed production line consisting of a product conveyance line and multiple parts supply lines, on the production line,
In order to avoid line stoppages or waiting for work as much as possible, a schedule for the production process is created based on the manager's empirical rules, and assembly work, etc. is performed according to the created schedule. ing.

(Problem to be solved by the invention) However, if the results do not match the created schedule plan, it is unclear whether there is a problem with the schedule itself or whether the actual results are really small. The problem was that it was not clear what kind of treatment should be taken. Furthermore, if it is not clear when and what kind of parts are needed, there is also the problem of having to keep more inventory than necessary.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to improve the credibility of the evaluation of the capacity of a multi-product mixed production line, as well as to enable setting of an appropriate planned production volume. The purpose is to provide a production line simulation method.

(Means for Solving the Problems) In order to solve the above problems, a simulation method for a multi-product mixed production line according to the present invention calculates the load amount for each process of each product flowing on a product conveyance line, and the load amount of each product flowing on a product conveyance line. Planned production volume, each line length and each line speed of the product transport line and parts supply line, workpiece loading time and workpiece unloading time for each process of the product transport line, and parts supply from the parts supply line to the product transport line. By inputting the time and the order in which each product is introduced into the production line, the operation of the product transport line and the parts supply line is simulated based on these input data, and based on the results of this simulation, each product is This is used to set the work start time and work end time for each process.

(Function) Load amount for each process of each product flowing on the product transportation line, planned production amount of each product, each line length and each line speed of the product transportation line and parts supply line, and each product transportation line. Input the work loading time and workpiece unloading time for each process, the parts supply time of the parts supply line to the product transport line, and the input order of each product to the production line, and from these input data, calculate the workpiece transport line and The operation of the parts supply line is simulated, and if there is overlap in the work in each process for each product, this is adjusted and the work start time and work end time for each process for each product are set. do.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a block diagram showing the electrical configuration of a device used in an embodiment of the present invention.

In the figure, a computer body 11 consisting of a CPU, ROM, RAM, etc. includes a keyboard 1 for inputting data.
A display device 13 to which the output of No. 2 is guided, and also displays production plan data, animation of the production line, etc.
The output of the computer main body 11 is led to a printer 14 which outputs the data displayed on the display device 13.

FIG. 1 is a flowchart showing one embodiment of the present invention, and the operation of the simulation method according to the present invention will be described below with reference to FIG. 2 as well. however,
In this embodiment, a case will be described in which the simulation method of the present invention is applied to a production line for unit housing.

When the operation starts, a message prompting you to enter data will be displayed (not shown), so follow the message and
Data regarding the product conveyance line that consistently performs operations from the loading of workpieces to the unloading of completed products is input (step 511).

Next, data regarding multiple parts supply lines that supply parts to be assembled to the workpieces flowing on this product transport line is input (step 512).
.

FIG. 3 shows a display screen displayed on the display device 13 based on data regarding the product transport line and data regarding the component supply line.

The data regarding the product conveyance line input in step 311 includes the layout of the product conveyance line, and the line length and line speed of each process. The data regarding the component supply line input in step S12 includes the layout of the component supply line, its line length, and line speed.

Regarding the layout of the product conveyance line, the overhang process (first process) 21, the outer wall girder process (second process) 23 via the buffer area 22, the outer wall girder process (third process) 24, and the buffer area 25. Composite work process (4th process to 8th process), staircase loading process (9th process) 3],
It consists of a partitioning process (10th process) 32, a pushing process (11th process) 33, and a bath core insertion process (12th process) 34. Further, the composite work process includes a first inner wall process (fourth process) 26, a second inner wall process (fifth process) 2
7. Electrical wiring process (6th process) 28, Eaves shutter process (7th process) 29, Gasket installation process (8th process) 3
Consists of 0.

The overhanging process 21, the external wall girder process 23, the external wall gutter process 24, the stair loading process 31, the partitioning process 32, the push-in process 33, and the bus core loading process 34 are processes in which the line is driven intermittently, and the workpiece is kept constant. Work is performed by stopping at the position, and the workpiece is moved according to a preset takt time.

In addition, the compound work process (4th process to 8th process) is a process in which the line is continuously driven, the workpiece moves at a constant speed, and the worker also moves as the workpiece moves. It looks like this. In addition, in this complex work process, the workable area for each process is set based on the workload in each process, the line length and line speed of each line, and the workpiece being worked on is If the workable area is exceeded, the corresponding line is stopped until the work is completed.

FIG. 7 shows an example of the workable area of each line. For example, if there are three workpieces in this workable area,
The worker first starts working on work A, then moves to the next work B when finished, and then moves on to the next work C.
If the work being worked on exceeds the boundaries of the workable area, the line is stopped.

In addition, the workpieces input into the buffer area 22.25 are
Since the workpieces are stored front-aligned, the intervals between the workpieces are constant. In addition, the buffer capacity of the buffer area 22.25 is
It is determined by the buffer length and the size of the work stored in that area.

Regarding the layout of the parts supply line, there is an outer wall girder side sub-assembly section 41 that supplies the outer wall girder side sub-assembly parts to the outer wall girder process 23 of the product delivery line, and an outer wall girder side sub-assembly section 41 that supplies the outer wall girder side sub-assembly parts to the outer wall girder process 24. A gable side sub-assembly line 42, a stair sub-assembly line 43 that supplies stair sub-assemblies to the stair input process 31, a closet sub-assembly process 44 that supplies push-in sub-assemblies to the closet process 33, and a bus core sub-assembly line 44 that supplies stair sub-assemblies to the bath core input process 34. It is composed of five lines of a bus core sub-assembly 45 that supplies the power, and each line is composed of a combination of a tact line 4a and a buffer line 4b. The takt line 4a is a line that is driven intermittently, and performs sub-assembly work by stopping at a fixed position on the line, and moves the workpieces in accordance with a preset takt time. Further, since the sub-assemblies input into the buffer line 4b are stored in a front-aligned manner, the intervals between the sub-assemblies are constant.

Following the input of the data that instructs the configuration of the production line above, the planned production volume of each product to be produced, the order in which each product is introduced into the production line, the workpiece loading time and workpiece for each process on the product transportation line. Unloading time and each sub-group line 41~
45, the parts supply time to each corresponding process is input (step 513).

Also, calculate and input the load amount for each process for each product (
Step 514).

The load amount for each process for each product is determined as follows.

That is, the computer main body 11 stores data (see Fig. 4) in a database indicating the names of parts and the number of parts required for the production of each product, and also the load amount of each part in each process described above. (See FIG. 5) is also stored in the database. This amount of load is determined in consideration of the number of workers assigned to each process. Therefore, the operator reads necessary data from each of these databases and calculates the load amount for each process of each product by the calculation shown in FIG. For example, the product Nal is composed of two A parts and three 8 parts as shown in Fig. 4, and the load amount is 1 minute for A part (however, the 1st part (used in the second process), and 2 minutes for part B (used in the second process). From these data, as shown in Figure 6, the load amount for each process of product NcL1 is 2 minutes (1 minute x 2) in the first process and 6 minutes (1 minute x 2) in the second process.
2 minutes x 3) However, in order to make the explanation easier to understand, the load amount of each process for the product 1 mentioned above is set to be less than the actual process and the number of parts is less than the actual number of parts. In reality, it consists of more steps and more parts.

When the input of these data is completed, the initial screen shown in FIG. 3 is displayed on the display device 13 (step 515).
, the simulation of the production line begins (step 516). However, in the initial state of each sub-assembly line 41 to 45, parts (sub-assembled parts) to be supplied to each workpiece flowing to the product conveyance line are packed up to the tip of each buffer line 4b. It is assumed that the vehicle is being transported.

In the simulation of the operation of the production line, first, the workpiece of the first product based on the production plan is carried from the loading station to the first process, the overhang process 21, and after completing the prescribed work in this process, the work is transferred to the buffer area. Export to 23.

After this, if it is possible to carry it into the overhang process 21, the work of the next product based on the production plan (the work of the same product if multiple pieces of the same product are produced in succession)
However, for the sake of convenience, a description of the simulation of this product will be omitted here.

The workpieces carried into the buffer area 23 are front-loaded and are in a state of waiting to be carried out. After this, the workpieces packed in the buffer area 23 are carried into the second process, the outer wall girder process 23, and the outer wall girder side sub-assembly parts supplied from the outer wall girder side sub-assembly part 41 are assembled. Then, the parts are carried into the third process, the outer wall end process 24, where the outer wall end sub-assembly parts supplied from the outer wall end sub-assembly line 42 are assembled, and then carried out to the buffer area 25. The workpieces carried into the buffer area 25 are front-loaded and are waiting to be carried out. Thereafter, the workpieces packed in the buffer area 25 are carried into the composite work processes, which are the fourth to eighth processes.

In this composite work process, since the work areas of each process 26 to 30 overlap, it is necessary to set the relationship between the works. However, two of the first inner wall process 26 and the second inner wall process 27
The two processes are in a dependent relationship, and the operations of both processes 26 and 27 cannot be performed in parallel. In addition, these inner wall processes 2
The four processes of 6.27, electrical wiring process 28, eaves shutter process 29, and gasket installation process 30 are independent, and can be performed in parallel. For example, the first inner wall process 26 and the electrical wiring process 28 are performed simultaneously and in parallel, and the second inner wall process 27 and the eaves shutter process 29 are carried out simultaneously.
and the gasket attachment step 30 can be performed simultaneously and in parallel. These relationships are set based on the amount of work load in each process determined above, and the line length and line speed of each line.

Thereafter, the workpieces that have completed the work in the composite work process are carried into the stair loading process 31, where the stair sub-assembly parts supplied from the stair sub-assembly line 43 are assembled, and then carried into the partitioning process 32. Then, the workpiece that has completed the work in the partitioning process 32 is carried into the push-in process 33, where the push-in sub-assembly parts supplied from the push-in sub-assembly line 44 are assembled. After the bus core sub assembly parts supplied from the bus core sub assembly process 45 are assembled, they are carried out to the unloading station. However, although the production line simulation described above describes the case where work is performed in all processes, some of the above-mentioned processes may be omitted depending on the product flowing on the product conveyance line. Of course. For example, the bath core sub-assembly process 45 is a process that is applied to the work that constitutes the bathroom, and is not applied to other works.

The above-mentioned simulation is performed sequentially for all products flowing on the line according to the production plan, and the work start time and work end time for each process of each product are determined (step 517). After that, in the overhang process 21 which is the first process, it is checked whether there is any overlap in time between the work that flows first and the work that flows next (steps S18, S19, 520). If the work end time of the workpiece and the work start time of the next workpiece overlap, the operation proceeds to step 321, and a correction is made to shift the work start time of the next workpiece later by the overlap. Next, in the second process, the outer wall girder process 23, it is checked whether there is any overlap in time between the work that flows first and the work that flows next (steps 318, S19,
520), if the work end time of the first workpiece and the work start time of the next workpiece overlap, the operation proceeds to step S21, and the work start time of the next workpiece is set by the overlapped time. Add a correction to move it later. Such operations are carried out up to the final step, the hash core charging step 34. In addition, in a compound work process, if the work being worked on exceeds the workable area, the line is stopped until the work is completed, so in this case as well, the work start time and work end time of the subsequent process are set on the line. Add a correction to move it back by the stop time (step S19゜S2
2,523).

In this way, the work start time and work end time of each process of each product that has been finally modified (i.e., the work start time and work end time set in seconds without duplication in each process) ). An example of a list of this data is shown in FIG. This data can be displayed on the display screen of the display device 13 by selecting screen display through menu selection (steps S24, 525). Furthermore, by selecting print from the menu selection (step S24, 526), a list of data can be printed out from the printer 14.

At the production factory, actual production is carried out using the established setting data (plan data) as target values.

If there is a large difference between production results and planned data, we will investigate the cause, identify the problem process or workpiece, and take countermeasures.
This will improve productivity.

(Effects of the Invention) The simulation method for a multi-product mixed production line according to the present invention is based on the load amount of each product flowing on the product transportation line for each process, the planned production amount of each product, the product transportation line and parts supply. Each line length and each line speed, the workpiece loading time and workpiece unloading time for each process on the product transport line, the parts supply time to the product transport line on the parts supply line, and the input of each product to the production line. The operation of the product transport line and parts supply line is simulated based on input data indicating the order, and the appropriate planned production volume for each product is set, as well as the work start time and work end time for each process. With this configuration, if there is a large difference between the simulation results and the actual results, the process or workpiece in question can be identified, and an immediate response can be taken, thereby increasing productivity. This has the effect of improving the

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing one embodiment of the present invention, and FIG.
The figure is a block diagram showing the electrical configuration of the device used in one embodiment of the present invention, Figure 3 is an explanatory diagram showing the animation screen displayed on the display device, and Figure 4 is the parts necessary for producing each product. Figure 5 is a table showing the load amount of each part in each process, Figure 6 is a table showing the load amount of each product in each process, Figure 7 is a table showing the load amount of each part in each process, and Figure 7 is a table showing the load amount of each part in each process. A diagram showing an example of the workable area of each line, and FIG. 8 is a diagram showing an example of a list of work start times and work end times. 1...Computer body 2...Keyboard 3...Display device 4...Printer

Claims (1)

[Claims] 1) A product transport line that performs the entire process from loading the workpiece to unloading the completed product, and multiple parts that supply parts for assembly to the workpieces flowing on this product transport line. A simulation method for a multi-product mixed production line consisting of a supply line, the load amount for each process of each product flowing on the product conveyance line,
The planned production volume of each product, each line length and each line speed of the product transportation line and the parts supply line, the workpiece loading time and workpiece unloading time for each process of the product transportation line, and the part supply line's The time for supplying parts to the product transport line and the order in which each product is introduced into the production line are input, the operation of the product transport line and the parts supply line is simulated based on these input data, and the results of this simulation are calculated. A simulation method for a multi-product mixed production line, characterized by setting the work start time and work end time for each process of each product based on