JPH10147268A - Production instruction system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce schedule adjusting man-hour when an equipment gets out of order by discriminating a product kind corresponding to a parts kind which is estimated to be shortage of products by the estimated result of a shortage of product estimation means and instructing an offline of the product kind from a main line. SOLUTION: A workstation 6 determines a car body on which subparts which are estimated to be shortage of products are mounted by a shortage of products estimation result within a file 41, refers to a main line production plan within a file 21, discriminates a car body in which such shortage of products is likely to be generated and prepares rejecting information on such car body by a rejecting vehicle discriminating part 42 as an offline instruction means. The rejecting information prepared is transmitted to an F/M line PLC at the outside, shortage of products information is written on a body so as not to flow a vehicle in which shortage of products is generated on a main line and the vehicle in which shortage of products is generated is automatically rejected at a prescribed rejecting point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a production instruction system for giving predetermined production instructions to a main line and a sub line, and more particularly to a system capable of reducing the number of steps for adjusting a schedule when a facility fails.

[0002]

2. Description of the Related Art In general, a production line of an automobile factory is a line of a mixed production system in which products having various specifications are mixed and produced. Taking the body assembly process as an example, the body assembly equipment is arranged along the flow of the body, and the flow consists of three main lines: floor main (F / M), body main (B / M), and metal line. (Main line)
And several tens of sub-assembly lines (sub-lines) for supplying sub-components to the sub-assembly lines. Parts completed on the sub-line are temporarily stocked as inventory, so that they can respond to fluctuations in demand on the main line (inventory compensation).

[0003] When a large equipment failure occurs in the sub-line for supplying parts to the main line due to inventory compensation, the safety stock set in advance cannot cover the shortage, and a shortage (stock shortage) occurs depending on the type of parts. Things happen. In the event that a sub-part is missing, on the main line, such a body is temporarily pushed out of the line (off-line) to adjust the schedule so as not to flow out of the part-out body.

[0004]

However, in such a conventional system, schedule adjustment at the time of equipment failure, that is, determination of stockout of a sub-line, indexing of a target body, and a pop-out instruction, etc., are performed. Since a series of operations are performed by workers at the site, such operations require a great deal of man-hours, and there is a certain limit in improving the productivity or production efficiency of the line.

[0005] The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a production instruction system capable of reducing the number of man-hours for adjusting a schedule in the event of equipment failure.

[0006]

In order to achieve the above object, an invention according to claim 1 comprises a main line for producing a plurality of types of products and a sub-line for supplying various necessary parts to the main line by inventory compensation. In a production instruction system that issues a predetermined production instruction to each of the above, in a production instruction system, based on predetermined data, a component inventory prediction means for predicting a change in the finished product inventory of the sub-line for each component type, and Parts demand forecasting means for forecasting changes in the number of parts to be supplied to the main line, and a forecast result of the parts inventory forecasting means and a forecast result of the parts demand forecasting means for determining whether or not a missing item has occurred for each part type. The product shortage prediction means for predicting, and the product type corresponding to the component type that is predicted to be out of stock is identified based on the prediction result of the shortage product prediction means, and the product type Serial and having a offline instruction means for instructing the offline from the main line.

According to the present invention, the parts inventory prediction means predicts the transition of the finished product inventory of the sub-line for each part type based on the predetermined data, and the parts demand prediction means performs the processing for each part type based on the predetermined data. Next, the change in the number of components to be supplied to the main line is predicted. The shortage prediction unit predicts whether or not a shortage has occurred for each component type based on the prediction result of the component inventory prediction unit and the prediction result of the component demand prediction unit. Then, the product type corresponding to the part type expected to be out of stock is identified, and the product type is instructed to go offline from the main line. As a result, even if a major equipment failure occurs in the sub-line, the product type corresponding to the predicted part type that is likely to be out of stock will automatically be ejected out of the main line, and the product type that is out of parts Automatically adjusts the schedule so that it does not flow on the main line.

According to a second aspect of the present invention, in the first aspect of the present invention, preferably, the parts inventory forecasting means includes a sub-line production tact, a sub-line in-process inventory, and a sub-line production plan for each part type. After obtaining the transition of parts supply by the main line production tact and the main line production plan, the current finished product inventory data, the finished volume data and the supply data, It is characterized in that the change of inventory is obtained.

According to the present invention, the subline inventory transition is calculated based on the subline production tact, the subline in-process inventory, the subline production plan, the main line production tact, the main line production plan, and the current finished product inventory data. Is predicted.

[0010] The invention according to claim 3 is the invention according to claim 2, wherein the in-process sub-line stock data is preferably calculated from sub-line input result data and sub-line production result data.

According to the present invention, the subline in-process stock is calculated based on the subline input result data and the subline production result data.

According to a fourth aspect of the present invention, in the second aspect of the present invention, preferably, the current finished product inventory data includes main line passing result data and sub line production result of a product type corresponding to the part type. It is characterized by being calculated from data.

In the present invention, the current finished product inventory data of the sub-part is calculated based on the main line passing result data and the sub-line production result data of the product type corresponding to the part type.

According to a fifth aspect of the present invention, in the second aspect of the present invention, the sub-line production plan is configured so that the missing part can be rear-order-produced based on the shortage information from the shortage predicting means. It is characterized by being rescheduled.

According to the present invention, the sub-line production plan is rescheduled based on the missing item information from the missing item predicting means so that the missing item target part is produced in the second-order production.

According to a sixth aspect of the present invention, in the first aspect of the invention, the component demand forecasting means should supply the main line to the main line for each component type based on a main line production plan and main line passage actual data. It is characterized in that a change in the number of parts is obtained.

According to the present invention, the transition of the number of components to be supplied to the main line is predicted by calculation based on the main line production plan and the main line passage actual data.

According to a seventh aspect of the present invention, in the first aspect of the present invention, there is provided an off-line means for extracting an off-line instruction target product type from the main line based on an output from the off-line instruction means.

In the present invention, the off-line means includes:
Based on the output from the off-line instruction means, the off-line instruction target product type is extracted from the main line. This allows
The product type corresponding to the part type that is predicted to be out of stock, which is the product type targeted for offline instruction, is automatically splashed out of the main line.

[0020]

Therefore, according to each of the first to seventh aspects of the present invention, the predicted transition of the finished product inventory of the sub-line and the production instruction (offline instruction) are linked to determine the type of the component that is expected to be out of stock. Since the corresponding product type is automatically pushed out of the main line, the number of steps for adjusting the schedule in the event of equipment failure is greatly reduced, and the productivity or production efficiency of the line is improved.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. Here, a case where the present invention is applied to a vehicle body assembling process is taken as an example.

FIG. 1 is a block diagram showing one embodiment of the production instruction system of the present invention. The vehicle body assembling process is roughly divided into a floor main (F / M) process 1 for assembling a floor serving as a base of the body in order along the flow of the body;
Assemble the body side, roof, rear panel, etc. on the base floor to create a cabin and build the body skeleton. Body main (B / M) process 2; A main line consisting of a metal line process (not shown) for attaching metal parts, and dozens of sub-lines for assembling intermediate assemblies (sub-parts) to be supplied to the main line, for example, cowl tops, rear waist, doors, etc. have. FIG. 1 shows a body main process 2 for simplicity.
1 shows only one sub-line 3 for supplying a sub-component M. In the main line, products (vehicles) of various specifications are mixed and flowed according to the production plan described later (mixed flow production method), and accordingly, the sub line 3 also has sub-parts of the type only corresponding to the vehicle specification. It is being produced. Parts completed in the sub-line 3 are temporarily stocked as inventory 4 so as to be able to cope with fluctuations in demand on the main line (inventory compensation).

A workstation (W / S) 6 for controlling the production line (for example, schedule management, inventory management, etc.) is connected to the factory host computer 5. In addition, each line is equipped with a process PLC (programmable logic controller),
It is connected to the workstation 6. For example, the floor main process 1 includes a PLC 7 (F / M line PLC)
Is provided, and a PLC 8 (B / M
Line PLC), and the sub-line 3 has a PLC 9
(Sub-line PLC). PLC for process
The production instructions and necessary data collection for each process are performed by 7 to 9.

An ID plate is attached to all of the works flowing through the line (the body flowing through the main line and the sub-parts flowing through the sub-line). The ID plate is
As is well known, it is an information medium that can freely read and write information, and stores work-specific information (for example, vehicle type information, specification information, work information, and the like). A data collection and writing station (ST) at the entrance and exit of each process for reading information on the ID plate and writing information on the ID plate by communicating with the ID plate.
Is provided. For example, data collection and writing ST10 and 11 are provided at the entrance and exit of the floor main process 1, respectively, and data collection and writing ST12 and 13 are provided at the entrance and exit of the body main process 2, respectively. And data exit ST1 at the exit
4 and 15 are provided. Each of the data collection and writing stations 10 to 15 is composed of an ID controller, an antenna, and the like, and is connected to the corresponding process PLCs 7 to 9, respectively.

The floor main process 1 includes a dispensing facility 16 as an off-line means for displacing the body out of the line.
Is provided. As will be described in detail later, the body on which the missing item information (spout information) is set is adjusted by the ejection facility 16 at a predetermined ejection point provided in the floor main process 1 for schedule adjustment. It is automatically ejected out of the line. Here, only the projecting equipment 16 of the floor main process 1 is shown, but this is because it is assumed that the equipment failure of the sub-line 3 that supplies parts to the body main process 2 and is not limited to this. Of course.

The workstation 6, as described above,
It has a function to manage the schedule of the main line. FIG. 2 is a functional block diagram of the workstation 6 for that purpose.

As shown in FIG. 1, the workstation 6 includes a production plan receiving section 20 for receiving a production plan from an external host computer 5, and a production plan receiving section 20 for receiving the production plan.
Has a production plan file 21 for storing the production plan received in the step S1. The production plan received from the host computer 5 is a daily production plan (daily plan) in which specifications and the number of units are determined.
Is a sequence plan (production sequence plan) that is sequenced in consideration of leveling according to the capacity of the line, and this is the production plan of the main line.

The workstation 6 stores the production plan in the file 21 and the file 22 set in advance.
A sub-line production plan calculation unit 23 for calculating a production plan (production sequence plan) of the sub-line 3 based on the part specifications therein; a sub-line production plan file 24 for storing the production plan calculated by the sub-line production plan calculation unit 23; It has a sub-line input instruction section 25 that outputs an input instruction to the sub-line 3 according to the sub-line production plan in the file 24. The output of the sub-line input instruction section 25 is sent to the external sub-line PLC 9, where a specific input instruction (sub-part production order) is issued to the sub-line 3.

Further, the workstation 6 has a subline production plan rescheduling section 26 for rescheduling the current subline production plan so that the missing parts are rearranged according to the shortage prediction result described later. I have. The subline production plan rescheduled by the subline production plan rescheduling unit 26 is updated and registered in the file 24.

Further, the workstation 6 receives the passing result data of the body main process 2 from the external B / M line PLC 8 as a means for monitoring the production progress of the sub-line 3 and managing the inventory. / M line passing result receiving unit 27, a sub-line production result receiving unit 28 for receiving the production result data of the finished product in the sub-line 3 from the external sub-line PLC9, and the input result data from the external sub-line PLC 9 to the sub-line 3. A sub-line input result receiving unit 29 for receiving
A sub-part inventory calculator 30 that calculates the current finished product inventory of the sub-parts based on the B / M line passage result data received by the / M line passage result receiver 27 and the sub-line production result data received by the sub-line production result receiver 28. And a sub-component completed product inventory file 31 storing the sub-component completed product inventory data calculated by the sub-component inventory calculation unit 30.
And a sub-component in-process for calculating an unfinished sub-component in-process inventory being produced in the sub-line 3 based on the sub-line production result data received by the sub-line production result receiving section 28 and the sub-line input result data received by the sub-line input result receiving section 29. And an in-process inventory file 33 for storing the in-process sub-component inventory data calculated by the in-process sub-component inventory calculation unit 32. In addition, B /
The M-line passing result data is obtained by reading the ID information of the body exiting from the body main process 2 in the data collection / writing ST13, and the sub-line production result data is the ID of the sub-part finished product exiting from the sub-line 3 in the data collection / writing ST15. The information is obtained by reading the information, and the sub-line input result data is obtained by reading the ID information of the parts entering the sub-line 3 in the data collection / write ST14.

The workstation 6 also includes a production plan in the file 21, a sub-line production plan in the file 24, a sub-line production tact and a main line production tact in the file 34 set in advance, and a sub-part finished product in the file 31. A stock transition estimating unit 35 as a part inventory estimating means for estimating the transition of the finished product inventory of the sub-line 3 based on the inventory and the sub-component in-process inventory in the file 33, and the inventory calculated by the inventory transition estimating unit 35 It has an inventory transition prediction result file 36 for storing transition prediction results.

Further, the workstation 6 sends the body floor main process 1 from the external F / M line PLC 7.
F / M line passing result receiving section 37 for receiving passing result data of the main line production plan and F
B / M as part demand forecasting means for predicting the body passing through the body main process 2 by calculation based on the F / M line passing result data received by the / M line passing result receiving unit 37
It has a line passage prediction section 38 and a B / M line passage prediction result file 39 for storing the B / M line passage prediction result calculated by the B / M line passage prediction section 38.
Since the B / M line passage prediction result relates to the order of the vehicle type and specifications of the body passing through the body main process 2, this data also predicts the transition of the number of sub-parts M to be supplied to the body main process 2. It has become something.

Further, the workstation 6 allocates sub-parts to be used for various bodies passing through the body main process 2 based on the inventory transition prediction result in the file 36 and the B / M line passing prediction result in the file 39. A shortage prediction unit 40 as a shortage prediction unit for predicting the occurrence of a shortage for each component type, and a shortage prediction result file 41 storing the shortage prediction result calculated by the shortage prediction unit 40
have. The shortage prediction result in the file 41 is used when rescheduling the subline production plan as described above.

Further, the workstation 6 obtains a vehicle body to which a sub-part which is predicted to be out of stock is attached based on the out-of-stock prediction result in the file 41, and
1, a protruding vehicle identification unit 42 as off-line instructing means for identifying a vehicle body that will cause such a part shortage and creating the protruding information of such a vehicle body; It has a projection information transmission unit 43 for transmitting the projection information created by the projection vehicle identification unit 42 to the external F / M line PLC 7. F / M that has received the projection information from the projection information transmission unit 43
The line PLC 7 sets the projection by writing the projection information to the ID plate of the corresponding body via the data collection writing ST10 at the entrance of the floor main process 1.

Next, the operation of the present system will be described with reference to the flowcharts of FIGS. First, an outline of the operation will be described. The production progress status of the sub-line 3 is monitored, predetermined data is created, and the transition of the finished product inventory 4 of the sub-line 3 is predicted for each component type. In other words, whether or not the supply is sufficient in time for the production plan of the main line with the stock 4 of the part M and the volume is calculated in time series. Thereafter, the stock transition prediction result is compared with the separately calculated B / M line passage prediction result to predict a component type in which a stockout occurs. Then, the vehicle causing the shortage is identified, and the shortage information (splashing information) is written on an ID plate attached to the body so that the vehicle does not flow along the main line, and automatically at a predetermined springing point. Splash out.

At this time, the workstation 6 that manages the schedule of the main line writes the work information to the ID plate of each body via the process PLCs 7 and 8 based on the production plan of the main line. In addition, each PLC
In steps 7 and 8, the IDs are read at the entrances and exits of the steps 1 and 2, respectively, and work instructions are sent to the automatic machine and results are sent to the workstation 6. On the other hand, also in the sub-line 3, the workstation 6 collects the results through the PLC 9 and manages the inventory.

Here, the above-described part outage check processing in the workstation 6 is performed periodically (for example, every 10 to 15 minutes) when an equipment failure of a specified value or more is detected in the subline 3. I have. As described above, for the vehicle in which the shortage is predicted as a result of the component shortage check processing, the setting of the projection information on the ID plate is performed via the PLC 7.

FIG. 3 is a flowchart showing the operation of the workstation 6. When the system is started, the workstation 6 receives the production plan (main line production plan) from the host computer 5 by the production plan receiving unit 20, and stores it in the file 21 (step S1). The workstation 6 issues a production instruction to each of the processes 1 and 2 by writing work information to the ID plate of each body via the process PLCs 7 and 8 based on the main line production plan.

Next, the sub-line production plan calculation unit 23
Then, the production plan (production sequence plan) of the subline 3 is calculated based on the production plan in the file 21 and the part specifications in the file 22 set in advance, and the result is stored in the file 24 (step S2). Based on the sub-line production plan, the sub-line input
An instruction to input into sub-line 3 is output to C9.

Steps S1 and S2 described above are so-called initial setting parts, and thereafter, various actual result data are received from each of the PLCs 7-9. More specifically, the B / M line passage result receiving unit 27 outputs the B / M line PLC 8
/ M line passing result data, the sub line production result receiving unit 28 receives the sub line production result data from the sub line PLC 9, similarly receives the sub line input result data from the sub line PLC 9, and receives the F / M line passing result receiving unit 37 Then, F / M line passing result data is received from the F / M line PLC 7 (step S3).

Next, the sub-part inventory calculator 30 calculates the current finished product inventory of the sub-parts based on the B / M line passage actual data and the sub-line production actual data received in step S3, and stores the result in the file 31. (Step S4).

The sub-component in-process inventory calculating section 32 calculates
Based on the sub-line production result data and the sub-line input result data received in step S3, the incomplete sub-component in-process stock being produced in the sub-line 3 is calculated, and the result is stored in the file 33 (step S5).

Next, the inventory transition prediction unit 35 generates a production plan in the file 21, a subline production plan in the file 24, a subline production tact and a main line production tact in the file 34, and a subpart in the file 31. Based on the finished product inventory and the in-process sub-component stock in the file 33, the transition of the finished product inventory of the subline 3 is predicted by calculation, and the result is stored in the file 36 (step S6). Note that, as described above, this processing is performed periodically (for example, every 10 to 15 minutes) when an equipment failure of a specified value or more is detected in the subline 3.

FIG. 4 is a flowchart showing the contents of the inventory transition prediction process in step S6. First, based on the production tact of the sub-line, the sub-component in-process stock, and the sub-line production plan, the transition of the sub-part production from the present time is calculated (step S21). An example of the result of the volume transition prediction is, for example, as shown in the graph of FIG.

Further, based on the production tact of the main line and the production plan of the main line, the transition of the supply of the sub-part from the present time is calculated (step S22). An example of the result of the component supply transition prediction is, for example, as shown in the graph of FIG.

Thereafter, based on the present finished product inventory data (initial value), the work volume data obtained in step S21, and the component supply data obtained in step S22, the following equation is used to calculate the subline 3 according to stock = stock + volume−supply. Calculate the transition (fluctuation) in the finished product inventory (Step S2)
3). An example of the result of the inventory fluctuation prediction is, for example, as shown in the graph of FIG. The result is stored in the file 36.

When the inventory transition prediction processing is completed, the B / M line passage prediction section 38 passes the body main process 2 based on the F / M line passage actual data received in step S3 and the main line production plan in the file 21. The body to be processed is predicted by calculation, and the result is stored in the file 39 (step S7). As described above, this data is a prediction of the change in the number of sub-parts M to be supplied to the body main process 2.

Next, the shortage prediction section 40 checks the file 36
Sub-parts to be used for various bodies passing through the body main process 2 are allocated based on the stock transition prediction results in the table and the B / M line passing prediction results in the file 39, and whether or not there is a missing part is determined for each part type. Predict and save results in file 41
(Step S8).

Thereafter, a vehicle body to which sub-parts which are predicted to be out of stock are found by the overturning vehicle identification unit 42 based on the out-of-stock forecast result in the file 41, and the main line production plan in the file 21 is obtained. With reference to the above, the vehicle body which may cause such a part shortage is identified, the projection information of the vehicle body is created (step S9), and this projection information is transmitted from the projection information transmitting unit 43 to the F / M. Line PLC
7 (step S10). The F / M line PLC 7 having received the overhang information writes the overhang information on the ID plate of the corresponding body via the data collection / write ST10 at the entrance of the floor main process 1 and sets the overhang. . As a result, the body in which the ejection information is set is set at the predetermined ejection point at the ejection facility 1
6 automatically pops out of the line.

Thereafter, the sub-line production plan rescheduling unit 26 reschedules the current sub-line production plan based on the result of the missing parts in the file 41 so that the missing parts can be produced in the second order. Update registration in the file 24 (step S11).

FIG. 5 is a flowchart showing the contents of the sub-line production plan rescheduling process in step S11. First, the current sub-line production plan is read from the file 24 (step S31). Next, after the out-of-stock prediction result (out-of-stock information) (for example, the specification B) is read from the file 41 (step S32), FIG. As shown in the drawing, the production order is rearranged so that the missing part (specification B) is produced in the second-order production (step S33). The rearrangement result is updated and registered in the file 24 as a new subline production plan.

Unless a system end command is input (step S12), the process returns to step S3 to repeat a series of processes.

Thus, the finished product inventory 4 of the subline 3
The movement prediction and the production instruction (management of the projecting vehicle) are linked, so that the body corresponding to the predicted sub-component of the missing item is automatically projected out of the main line.
The man-hour for schedule adjustment at the time of equipment failure is greatly reduced, and the productivity or production efficiency of the line is improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a production instruction system of the present invention.

FIG. 2 is a functional block diagram of the workstation in FIG. 1;

FIG. 3 is a flowchart illustrating an operation of a workstation.

FIG. 4 is a flowchart showing the contents of a stock transition prediction process of FIG. 3;

FIG. 5 is a flowchart showing the contents of a sub-line production plan rescheduling process of FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Floor main process (main line) 2 ... Body main process (main line) 3 ... Subline 4 ... Inventory 6 ... Work station (parts inventory forecasting means, parts demand forecasting means, stockout forecasting means, offline instruction means) 16 ... Dispensing equipment (offline means)

Claims (7)

[Claims] 1. A production instruction system for issuing a predetermined production instruction to a main line for producing a plurality of types of products and a sub-line for supplying various parts necessary to the main line by inventory compensation, wherein: Parts inventory prediction means for predicting changes in the finished product inventory of the sub-line for each part type, and parts demand prediction means for predicting changes in the number of parts to be supplied to the main line for each part type, with predetermined data, A shortage prediction unit that predicts whether or not a shortage has occurred for each component type based on the prediction result of the component inventory prediction unit and the prediction result of the component demand prediction unit; Offline instructing means for identifying a product type corresponding to a component type predicted to be the same, and instructing the product type to be offline from the main line. A production instruction system, comprising: 2. The parts inventory forecasting means according to claim 1, wherein:
Based on the sub-line production tact, sub-line in-process inventory and sub-line production plan, the change in parts volume is calculated,
And, after obtaining the transition of the parts supply according to the main line production tact and the main line production plan, it is requested to obtain the transition of the finished product inventory of the sub-line based on the current finished product inventory data, the volume data and the supply data. The production instruction system according to claim 1, wherein: 3. The production instruction system according to claim 2, wherein said subline in-process inventory data is calculated from subline input result data and subline production result data. 4. The production instruction system according to claim 2, wherein said current finished product inventory data is calculated based on main line passing result data and subline production result data of a product type corresponding to said part type. 5. The production according to claim 2, wherein the sub-line production plan is rescheduled based on the shortage information from the shortage prediction means so that the missing target part is produced in a second-order production. Instruction system. 6. The component demand forecasting means according to claim 1, wherein a change in the number of components to be supplied to said main line is determined for each component type based on a main line production plan and main line passage actual data. Production instruction system. 7. The production instruction system according to claim 1, further comprising an off-line means for extracting an off-line instruction target product type from said main line based on an output from said off-line instruction means.