JPH04205169A - Method and device for production planning - Google Patents

Abstract

PURPOSE:To speedily take a proper countermeasure and correct a plan by using the plan settling knowhow that skilled persons have when a person who is unfamiliar with the method for correcting the production plan upon occasion settles the production plan of a production line by using a computer. CONSTITUTION:A production progress state prediction part 3 predicts the production progress state when production is carried out according to a source production plan by using a knowledge base 4 based upon the plan settling knowhow that the skilled persons have. Then a countermeasure plan determination part 6 points out the factor of a predicted bottleneck state in the production progress by using a similar knowledge base 4 and determines the countermeasure plan for the production plan so as to solve the bottleneck state. A plan generation part 2 generates the source initial production plan firstly and passes it as input information to a production progress state predicting means.

Description

[Detailed Description of the Invention] [Industrial Application Field] When a person who is not familiar with how to modify a production plan according to the situation uses a computer to draw up a production plan for a production line,
This invention relates to a production planning method for correcting plans by taking appropriate measures by using planning know-how possessed by experts.

[Conventional technology]

As described in Japanese Unexamined Patent Publication No. 59-37033, the conventional system calculates the daily operating hours of lines and equipment, the maximum or minimum amount of work, and allocates work to lines and equipment when formulating production plans. It was necessary to set the priority order etc. in the form of rules in advance.

For this reason, if a desired plan cannot be drawn up, trial and error is required, such as changing some of the preset conditions and repeating the above steps again, which requires a large amount of time for data processing. .

[Problem to be solved by the invention]

When a skilled production planning person formulates a production plan using the above-mentioned conventional technology, he or she must use past empirical rules such as what measures should be taken and how much should be changed in order to correct undesirable plans. By using this method, the plan can be revised with the minimum number of trials necessary. The purpose of the present invention is to accumulate the planning know-how possessed by such experts in a computer and use it according to the situation, so that even a person who is not familiar with how to modify a production plan can create a desired production plan. The purpose of the present invention is to provide a production planning method that can plan a production plan with a minimum number of trials.

[Means to solve the problem]

The purpose of the present invention is to eliminate the above-mentioned problems of the prior art, and to utilize the planning know-how of experts according to the situation, so that even a person who is not familiar with how to modify a production plan can create a desired production plan. The object of the present invention is to provide a production planning method that can be planned with a minimum number of trials.

The present invention is aimed at predicting the production progress status when production is executed according to the draft production plan, identifying the cause of a gap in the production process, and overcoming the gap situation when formulating a production plan in a manufacturing shop. A production planning method that determines countermeasures for production planning, which uses a knowledge base based on the know-how of experienced planners to predict production progress, identify the causes of gap situations, and improve production planning. As a means of realizing a method for determining countermeasures to overcome the situation in the planning, a knowledge base based on the planning know-how of a skilled planner and a production plan draft using this knowledge base are used. A method for predicting the production progress when production is executed based on the knowledge base (a production progress prediction means), and a method for extracting the factors of the gap situation in the production progress predicted using the knowledge base, and calculating the gap situation. By providing a means for determining countermeasures for production planning to overcome problems (countermeasures determining means), it is possible to formulate a desirable production plan with a minimum number of trials. Further, by using similar means, it is possible to determine the desired operating conditions of the manufacturing shop with a minimum number of trials.

Furthermore, by providing a means for creating and viewing an initial production plan draft (plan creation means), it is possible to shorten the time required to formulate a desirable production plan and compensate for the shortage of engineering personnel.

Furthermore, by providing a means for modifying the production plan based on the determined countermeasure plan (plan modification means) and a means for outputting the finally obtained production plan (plan output means), it is possible to achieve desired production. Make plans easy to confirm and operate.

Furthermore, by providing a means for interactively modifying the final production plan (plan dialogue modification means), users can easily change the contents of the obtained production plan as necessary. do it like this.

Furthermore, there is a means to input the information necessary for formulating a production plan (
information input means); information storage means for storing the information);
By providing a means for interactively changing the information (information dialogue changing means), the user can change the conditions for production planning as necessary.

Furthermore, by providing a means (knowledge acquisition means) that allows experienced planners to accumulate and change their planning know-how in an interactive manner, even experienced planners who are not familiar with computers can directly accumulate their own know-how on a computer. To enable maintenance.

Furthermore, by providing a means for displaying a series of processing steps when formulating a production plan (processing step display means),
To easily explain to a user the process of obtaining a final plan, and to enable a person who is not familiar with the method of modifying a production plan to learn the method of modifying the production plan.

Furthermore, by providing a means (knowledge specifying means) for specifying at least one of the name of the knowledge base used to identify roadblock factors and decide on countermeasures, or the name of an expert who has registered knowledge in the knowledge base, , to be able to create production plans that depend on the person in charge.

Furthermore, by providing a means (measure plan designation means) for specifying at least one of the countermeasure items to be implemented or their order in relation to multiple countermeasure items among the determined countermeasure plans, judgments by experts can be directly influenced. be able to add.

Furthermore, when outputting (displaying) the final production plan, output data can be protected by providing a means for specifying at least one of the name of the output garment or the output device (output destination specifying means). Make it.

Furthermore, by using at least one of a light pen and a mouse as an information input means, and providing a means (operation guiding means) for displaying a menu screen, a message, etc. to guide operations, it is possible to use at least one of a light pen and a mouse to input information. To enable easy operation even by people (unaccustomed to keyboard operations).

[Effect]

First, the production progress forecasting method uses a knowledge base based on the planning know-how of a skilled planner to predict the production progress when production is executed based on the original production plan, and then develops a countermeasure plan. The determining means uses the same knowledge base to extract the factors that will cause the predicted gap in production progress, and determines countermeasures for the production plan to overcome the gap.

In addition, the plan creation means first creates an initial production plan draft and passes it to the production progress prediction means as input information.

Further, the production plan is corrected based on the determined countermeasure plan by the plan modification means and the plan output means, and the finally obtained production plan is output.

Further, the user interactively corrects the finally obtained production plan as necessary using the plan dialog modification means.

Further, the information input means, the information storage means, and the information interaction change means input and store information necessary for formulating a production plan, and the information can be changed interactively by the user as necessary.

In addition, the knowledge acquisition means allows the skilled planner to accumulate and change his or her own planning know-how in an interactive manner as necessary.

Further, if necessary, a series of processing steps in formulating a production plan is displayed by the processing step display means.

In addition, the knowledge specifying means allows the user to specify at least one of the names of the knowledge base used to identify roadblock causes and determine countermeasures, or the name of an expert who has registered knowledge in the knowledge base, as necessary. specify.

Further, by using the countermeasure designating means, the expert designates at least one of the countermeasures to be implemented or the order thereof among a plurality of countermeasures among the countermeasures determined as necessary. Further, when outputting (displaying) the finally obtained production plan, the user specifies at least one of the name of the output unit or the output device as necessary by the output destination specifying means.

Further, the user uses a light pen, a mouse, etc. as an information input means to execute a series of processes according to a menu screen, a message, etc. using the operation guidance means.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings. FIG. 1 shows the system configuration of this embodiment.

This system includes input devices (input section 8) such as a keyboard and disk drive for inputting information such as product assembly plans, line operating conditions, progress results, etc., and output devices (input section 8) such as displays and printers for outputting the created production plan. Output section 9
), a production control database (storage unit 1) that provides production control information necessary for planning production plans such as parts information and line information, and an initial production plan draft based on product assembly plans and necessary production control information. a requirements planning program (plan creation unit 2), a program (forecast condition setting unit 3a) that sets forecast conditions for production progress based on the production plan draft;
A production progress prediction simulator (production progress prediction unit 3) that simulates the production progress predicted when production is executed based on the production plan draft;
When a delay in delivery date is predicted, a program (blockage factor extraction unit 5) that extracts the cause (bottleneck line that causes delay in delivery date) is set, and conditions for predicting the production progress based on the production plan draft are set. A knowledge base (Knowledge Base 4) that stores the planning know-how of experts, which is used as an evaluation standard for determining the rules and causes (bottleneck lines) of crossroad situations (delivery delays), to overcome crossroad situations (delivery delays). A program (countermeasure decision unit 6) that determines countermeasures (plans for adjusting bottleneck line capacity and workload), and a program (planning It consists of a draft revision section 7).

FIG. 2 shows the overall processing procedure of the present invention. First of all, the requirements planning program is used to create product assembly plans, progress records,
An initial production plan is drawn up based on line operating conditions, parts, and line information (10-20). Next, conditions for predicting the production progress are set based on the know-how (rules) of experienced planners, and the production progress is predicted based on the production progress that would be expected if production was executed based on the initial production plan draft. Simulation is performed using a simulator (30). Here, if a gap in production progress (delivery delay) is predicted,
The planning know-how of experts is used as an evaluation standard for determining the cause (bottleneck line) of the crossroads situation (delivery delay), and the bottleneck line is extracted (40 to 50).

Furthermore, as a countermeasure to overcome the crossroads situation (delivery delay), a plan for adjusting the bottleneck line capacity and workload will be determined60), and based on the countermeasure, the production plan and line operating conditions will be revised. (70). The production progress prediction simulator again simulates the production progress of the revised production plan, repeats this procedure until an executable (no delivery delay) plan is obtained, and outputs a certain final one (80). .

Figure 3 shows an example of a multi-stage parts processing/assembly shop as a target model for production planning. The boxed area indicates the knee assembly process, and each process consists of one or more lines. In the example, each processing and production process is based on the production plan for the product assembly process shown in the figure (to ensure that each process can produce in time for the delivery date of the subsequent process so that the amount of parts can be supplied by the product assembly planning mill). An example of creating a production plan for an assembly process is shown below.

Figure 4 shows the functional configuration of the requirements planning program that creates the initial production plan. Here, the production plan for the product assembly process, the progress record of each processing/assembly process (21), the inventory amount for each component, the production period (22), and the initial plan (hereinafter referred to as the planned order table) (23) Create. This is a collection of work orders consisting of part names, production quantities, and delivery dates (production start dates for subsequent processes). In the system of this embodiment, MRP (Material
ial Require-ments Plannin
g) method is used.

FIG. 5 shows the functional configuration of the production progress prediction simulator. The program (prediction condition setting unit 3a) for setting prediction conditions for production progress based on a production plan, explained in FIG. 1, operates as one function of the production progress prediction simulator in this embodiment. Here, the planned order table (23) which is the output of the requirements planning program,
Based on the prediction conditions (detailed operating conditions for each line) set using production management data (22) and knowledge base (4) (30a), work assignments to each line are determined by simulation, and work progress for each line is determined. , predict the workload, predict inventory trends by parts, calculate the average number of days of delay by line (30), and calculate the delay status of each work order (31).
a) Output the operating status for each line (31b) and the inventory transition status for each part (31c).

Here, we will discuss the know-how (rules) associated with setting prediction conditions that experienced planners have.

In order to predict the production progress status, the prediction conditions are the allocation order between work orders, the work start date, the size of each work order (production volume), and detailed operating conditions of each line (capacity,
It is necessary to appropriately set the production period etc. according to the operating time). In making this setting, experienced planners use certain setting rules based on past experience. Therefore, these rules are made into a knowledge base, and based on this knowledge base, the allocation order among work orders, work start date, and production period for each work order are determined. In the system of this embodiment, this function is included in the processing of the production progress prediction simulator, so it will be specifically explained in the production progress prediction procedure.

FIG. 6 shows a schematic procedure for predicting the production progress status. First, from the work order group in the planned order table, select the work to be simulated according to the rules set in the knowledge base (310), and calculate the expected start date (310).
20). Setting rules regarding the order of allocation are, for example, ■, the order of the work with the earliest delivery date, the order of the work in which the parts necessary to produce the planned production volume are the earliest, and the order of the work with the highest production technology priority (1 (adapted in the order of ~m), these rules depend on the manufacturing shop and are the know-how possessed by skilled planners. Next, based on the set rules for determining the production period, the work is assigned to the specified line according to each work order size (production volume) and line operating conditions, and the expected delivery date (the day after the expected completion date)
330), and the production period is calculated from the expected start date and expected delivery date (340). For example, the setting rule for determining the production period is as follows: ■ Line A: The work order size (planned production volume) for part These rules are based on the know-how possessed by experienced planners. The above operations are executed for all work orders (350), and the average production period for each line is calculated (360).

Figure 7 shows the procedure for calculating the expected delivery date. First, the expected start date of the work order is calculated according to the setting rule (321a) in the knowledge base (321), and the work amount corresponding to the production amount is assigned to the designated line (322). For example, the rules for setting half-day work clothes are: ■, the earliest mill when there is space on the line■, the earliest when the parts necessary to produce the planned production volume are available■, and the earliest mill where production can be carried out ahead of schedule (compare ■ to ■). , set the latest date as the expected start date), these rules depend on the manufacturing shop and are the know-how possessed by experienced planners. Next, the daily warehousing/output amount and inventory amount of the part associated with the allocation are calculated (323). If the assignment of the work order is successful, calculate the expected delivery date (the next day of the final work assignment) (324 to 325); if unsuccessful, calculate the line capacity shortage or the shortage of child parts (324-325). 324-3
26).

FIG. 8 shows an example of the production progress prediction result (31). In addition, the line operation status predicted in Figure 9 (31b),
Parts inventory trends predicted in Figure 10 (31c)
- Give an example of each. These prediction results are used as data when adjusting bottleneck line capacity and workload as a way to overcome delivery delays.

As a result of predicting the progress of production as described above, if a delay in delivery is not predicted, the proposed production plan is output as a final result (an executable production plan).

Figure 11 shows the procedure for extracting roadblock factors using planning know-how. Here, we will explain the planning know-how of experts.

Since the start and expected delivery dates of each work order are related to each other due to the precedence relationship of the processing and assembly processes, the average number of days of delay for each line is also related to each other. Therefore, when adjusting line capacity and workload, the following questions should be asked: (1) How many days are the true delays occurring on the line? (2) In what order should capacity/load adjustments be made to the lines that are experiencing delays? It is necessary to select the target line by considering the following two points.

By the way, experts use their know-how to evaluate the production status of the line, such as ``Good production status on line A means a production period of 3 days and a daily production of 3000 units...'' Countermeasures are being taken wisely. This know-how does not provide specific steps to overcome a crossroads situation, but rather rules for determining the necessity of countermeasures, such as ``Which line is the problem?''

Here, we use this know-how as a determination rule to identify bottlenecks that cause delivery delays. In the example of Fig. 12, the experience value (line T-C
The good production status of YLI is that the average production period is 3 days, the average daily production is 3000 pieces, and the good production status of line T-CY L 2 is...) (51) and the predicted value that is the output of the simulator ( The predicted production status of line T-CYLI is
The average production period is 5 days, the average daily production is 3000 pieces, and the predicted production status for line T-CYL2 is...) (31a)
Compare the line T-CYL with the largest difference.
1 is identified as the biggest cause of delivery delay (50). Therefore, it is necessary to first take measures for the line T-CYL1.

Figure 12 shows the procedure for determining countermeasures to overcome the road situation. In order to overcome delivery delays, it is necessary to quantitatively understand how measures for workload and operating time affect production periods and production capacity. In this embodiment, a mathematical model as shown in FIG. 12 is used. This model is a behavioral model that can quantitatively analyze the relationship between workload, production period, and production capacity (61-62). This behavior slam is calculated and stored in advance for all lines (this work is possible by accumulating production control data and mechanical calculation). Then, we use this opportunity to concretely decide on adjustments to line capacity and workload to prevent delivery delays. In the example of line T-CY L 1 in Figure 11, the predicted average production period is 5 days, so the appropriate value is 3.
It is clear from the behavior slam data that the plan needs to be revised so that the workload amount becomes 3,500 items in order to reduce the number of days (experience points that are know-how). However, along with this, the production capacity will also drop to 2,500 pieces, as revealed by the behavior data. Therefore, in order to bring the daily production volume to the appropriate value of 3,000 pieces (experience, which is know-how), the line capacity is adjusted by setting overtime of 1 to 5 hours, which corresponds to the difference of 500 pieces ( 6o).

In this way, by sequentially determining countermeasure plans for the lines that require countermeasures, which are ordered based on the above-mentioned know-how, the expected occurrence of delivery delays can be eliminated.

In accordance with the countermeasure plan determined as above, the production plan and line operating conditions are revised, and the production progress prediction simulator is used again to determine whether the revised plan is acceptable (all delivery delays have been resolved and the plan can be executed). ). if,
If a new delivery delay is predicted, the plan is revised according to the procedure described above, and this process is repeated until an executable production plan is obtained, and a final draft is output.

The basic functions of this system have been described above.

Next, we will discuss the extended functions. FIG. 13 shows the configuration of an expansion system according to another embodiment of the present invention.

In addition to the basic functions described in FIG. 1, this system includes an interaction processing section (1o) corresponding to each processing function. Hereinafter, the detailed functions will be explained in order.

FIG. 14 shows an example of the operation guidance function. With this function, it is possible to successively click desired items from the process item name group (101a) using the mouse and proceed with the process without having to be aware of the keyboard. This example is the initial screen of the system of this embodiment.

FIG. 15 shows an example of a dialog change function for input information.

This feature allows you to interactively modify input information displayed in tabular format. Therefore, the user can change the operating conditions of the manufacturing shop when making plans as necessary. In this example, line master information (10
(10) urges partial revision of 2b).

FIG. 16 shows an example of the knowledge base selection function. This function allows the user to select the most appropriate knowledge base from a plurality of different knowledge bases that exist in the same workplace or between workplaces.

In this example, from among three different knowledge bases (102c) in the cylinder general assembly shop, knowledge base 3 suitable for this case is selected using the name of the skilled person as a key (101c).

FIG. 17 shows an example of the dialog change function of the planning know-how. This feature allows you to interactively accumulate or modify parts of your knowledge base. In this example, knowledge base 3 in the cylinder assembly shop shown in Figure 3 is used.
Partial correction of (102d) is encouraged (101d).

FIG. 18 shows an example of the countermeasure designation function. With this function, it is possible to change the order in which each of the adjustment items in the determined capacity/load adjustment plan is taken (measure order). In this example, the capacity/load adjustment order (102e) for multiple lines that produce the same part on the same day
(101e).

FIG. 19 shows an example of the output destination designation function. This function allows you to instruct how to output the created production plan draft (102f) to a specified file or printer (
101f).

FIG. 20 shows an example of the dialog correction function for the production plan draft. This function allows the user to interactively modify the created production plan.

In this example, the production plan (102g) displayed in table format
(101g).

FIG. 21 shows an example of the line table display function of the plan proposal.

This function allows you to check and operate the created production plan in a line table format. Furthermore, it is possible to compare the original draft and revised draft in line table format, and to search using lines, parts, and dates as keys (101h). In this example, the line T-
The production plan draft (102h) of CYL l is displayed in a line chart [Effects of the invention] The present invention predicts the production progress status when production is executed according to the production plan draft when formulating a production plan in a manufacturing shop. , a production planning method that identifies the causes of a gap in production progress and determines countermeasures for production planning to overcome the gap, and is based on knowledge based on the know-how of skilled planners. Skilled planning is a means of using the base to predict the production progress, identify the causes of the gap situation, and decide on countermeasures to overcome the gap situation in the production plan. a knowledge base based on a person's planning know-how, a means for predicting the production progress when production is executed based on a draft production plan using the knowledge base, and a means for predicting the production progress predicted using the knowledge base. By providing a means to identify the factors behind the above-mentioned conflict situation and determine countermeasures for production planning to overcome the conflict situation, it is possible to formulate a desirable production plan with a minimum number of trials. becomes. Further, by similar means, it becomes possible to determine the desired operating conditions of the manufacturing shop with a minimum number of trials.

Furthermore, by providing a means for creating an initial production plan draft, it is possible to shorten the time required to formulate a desirable production plan and compensate for the shortage of engineering personnel.

Furthermore, by providing a means to modify the production plan based on the determined countermeasure plan and a means to output the final production plan, it is possible to easily confirm the desired production plan.
It becomes possible to operate the system.

Furthermore, by providing a means for interactively modifying the finally obtained production plan, the user can easily change the contents of the obtained production plan as necessary.

Furthermore, by providing a means for inputting information necessary for formulating a production plan, and a means for storing and interactively changing this information, users can change the conditions for formulating a production plan as necessary. becomes possible.

Furthermore, by providing a means for interactively accumulating and modifying the planning know-how of experienced planners, even experienced planners who are not familiar with computers can directly accumulate and maintain their own know-how on a computer. becomes.

Furthermore, by providing a means to display the series of processing steps involved in drafting a production plan, it is possible to easily explain to the user how the final draft was obtained, and revisions can be made by people who are not familiar with how to revise production plans. It becomes possible to learn methods.

Furthermore, by providing a means for specifying at least one of the name of the knowledge base used to identify roadblock factors and decide on countermeasures, or the name of an expert who has registered knowledge in the knowledge base, it is possible to It becomes possible to create a production plan based on the

Furthermore, by providing a means for specifying at least one of the countermeasures to be implemented or the order of the countermeasures among the determined countermeasures, it is possible to directly add judgment by experts. Become.

In addition, when displaying (displaying) the final production plan, at least one of the names of the output clothes or the display device
By providing a means for specifying one, output data can be protected.

Furthermore, by using at least one of a light pen and a mouse as a means of inputting information, and by providing a means of displaying menu screens and messages to guide operations, it is possible to input information even if the user is not familiar with computers (not familiar with keyboard operations). ) Even a person can easily operate it.

[Brief explanation of the drawing]

Figure 1 is a system configuration diagram according to the present invention, Figure 2 is a diagram showing the overall processing procedure of the present invention, Figure 3 is a diagram showing an example of a multi-stage processing/assembly shop, and Figure 4 is an initial production plan. Figure 5 is a diagram showing the functional configuration of the draft creation unit, Figure 5 is a diagram showing the functional configuration of the production progress prediction condition setting unit and the production progress prediction unit, and Figure 6 is an overview of the production progress prediction procedure. , FIG. 7 is a diagram showing the details of the production progress prediction procedure, FIG. 8 is a diagram showing an example of the production progress prediction result, FIG. 9 is a diagram showing an example of the predicted line operation status, and FIG. The figure shows an example of predicted parts inventory trends, Figure 11 is a diagram showing the procedure for identifying the cause of a gap using planning know-how, and Figure 12 is a diagram for determining countermeasures to overcome the gap situation. FIG. 13 is a diagram showing the configuration of an expansion system as another embodiment of the present invention, FIG. 14 is a diagram showing an example of an operation guidance function, and FIG. 15 is an example of a dialogue change function of input information. Figure 16 is a diagram showing an example of the knowledge base selection function, Figure 17 is a diagram showing an example of the dialog change function for planning know-how, Figure 18 is a diagram showing an example of the countermeasure designation function, 19
20 is a diagram showing an example of the output destination designation function, FIG. 20 is a diagram showing an example of the dialog correction function of the production plan draft, and FIG. 21 is a diagram showing an example of the line table display function of the plan draft. Figure 1 Figure 2 Figure 4 Figure 6 Figure ri' Figure 8 Figure 9 3,1b O() n Figure 13

Claims (1)

[Claims] 1. In formulating a production plan in a manufacturing shop,
Predict the production progress when production is executed according to the original production plan, identify factors that cause gaps in production progress,
This is a production planning method that determines countermeasures for production planning to overcome the gap situation, and uses a knowledge base based on the know-how of experienced planners to predict production progress and A production planning method characterized by being able to formulate a desirable production plan with a minimum number of trials by identifying the factors of the situation and determining countermeasures to overcome the conflicting situation in the production plan. 2. A device that implements the method described in item 1 above, in which a knowledge base is based on the planning know-how of a skilled planner and production is executed based on a draft production plan using the knowledge base. means for predicting the production progress of;
By using the knowledge base to extract the factors of predicted production progress and determine countermeasures for production planning to overcome the production progress,
A production planning device that is capable of formulating a desired production plan with a minimum number of trials. 3. A device for realizing the method described in item 1 above, comprising a knowledge base based on the know-how of a skilled planner;
means for predicting the progress of production based on the draft production plan using the knowledge base; means for extracting the factors of the predicted gap in production progress using the knowledge base;
A production planning device characterized in that it is capable of determining desirable operating conditions for the manufacturing shop with a minimum number of trials by being equipped with means for determining countermeasures to overcome the situation. 4. The apparatus according to item 2 above, characterized in that by providing a means for creating an initial production plan draft, the time required to formulate a desirable production plan can be shortened and the shortage of construction personnel can be compensated for. production planning device. 5. The device described in item 2 above is capable of creating a desired production plan by providing means for modifying the production plan based on the determined countermeasure plan and means for outputting the finally obtained production plan. A production planning device that is characterized by easy confirmation and operation. 6. In the device described in paragraphs 2 and 5 above, by providing a means for interactively modifying the finally obtained production plan, the user can modify the contents of the obtained production plan as necessary. A production planning device characterized in that it can be easily changed. 7. The device described in Items 2 and 4 above is provided with a means for inputting information necessary for formulating a production plan, and a means for storing and interactively changing the information, so that the user can meet his/her needs. A production planning device characterized in that conditions for production planning can be changed accordingly. 8. In the device described in item 2 above, by providing a means for interactively accumulating and modifying the planning know-how of experienced planners, even experienced planners who are not familiar with computers can directly write their own information to the computer. A production planning device that is characterized by the ability to accumulate know-how and perform maintenance. 9. In the device described in items 2 and 5 above, by providing a means for displaying a series of processing steps when formulating a production plan, it is possible to easily explain to the user how the final plan was obtained, and to improve production A production planning device characterized in that a person who is not familiar with the method of modifying a plan can learn the method of modifying the plan. 10. The device set forth in item 2 above, including means for specifying at least one of the name of a knowledge base used for extracting roadblock factors and determining countermeasures, or the name of an expert who has registered knowledge in the knowledge base. A production planning device is characterized in that by providing it, it is possible to create a production plan that depends on the workplace and the person in charge. 11. In the device set forth in item 2 above, by providing a means for specifying at least one of the countermeasures to be implemented or the order thereof with respect to a plurality of countermeasures among the determined countermeasures, it is possible for an expert to A production planning device characterized by being able to directly add judgments based on 12. The apparatus according to items 2 and 5 above, by providing means for specifying at least one of the name of the output table or the output device when outputting (displaying) the finally obtained production plan, A production planning device characterized by the ability to protect output data. 13. The device according to item 2 above, wherein at least one of a light pen and a mouse is used as the information input means,
A production planning device characterized in that it can be easily operated even by people who are not familiar with computers (unaccustomed to keyboard operations) by providing means for displaying menu screens, messages, etc. to guide operations. 14. A knowledge base characterized by storing prediction results of production progress and planning know-how of a skilled planner in association with each other.