JPH05143612A - Production system design supporting device - Google Patents

Abstract

PURPOSE:To surely design an optimum production system in a short time without requiring many experts. CONSTITUTION:Production condition data of a production condition base 2 and process condition data of a process condition base 3 simulate the operation or the like of equipments in a production line by a process simulation means 1 to obtain simulation results such as a working rate. It is evaluated by a condition optimizing means 5 whether simulation results satisfy a target index or not and if the evaluation result indicates that simulation results do not satisfy the target index, production condition data stored in the production condition base 2 and process condition data stored in the process condition base 3 are changed in accordance with a preliminarily determined change condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a production system design support device for supporting the setting of various conditions such as the production sequence of products on a production line, the equipment in the line, and the ability of a worker.

[0002]

2. Description of the Related Art A production system is one in which a plurality of facilities for processing, for example, are arranged to form a production line, and various parts are supplied to the production line to produce a product. When designing such a production system, the expert considers the production conditions such as the production sequence of the products to be manufactured, the number of productions, the delivery time, and the process conditions such as the number of equipments, their capacity, line form, and workers. , We are evaluating the model of the production system. In this case, a specialist performs model evaluation of such a production system on a desk or using a simulation device.

By the way, in such model evaluation, the experience and intuition of an expert are often used, and the evaluation result becomes qualitative. Therefore, until the optimum production system is designed, the simulation results for the production system model and its production conditions and process conditions are repeatedly reviewed.

For this reason, many experts in system design are required for designing a production system, and it takes a lot of time to design an optimum production system.
Further, since the evaluation of the production condition and the process condition depends on the experience and intuition of a specialist, it is not always possible to surely obtain the optimum production system. Therefore, it takes a lot of time to start up the production system because the production system needs to be corrected at the stage of shifting the production system model to execution.

[0005]

As described above, many experts are required for designing a production system, and it takes a lot of time to design the production system, and it is certain that an optimal production system can be obtained. Not exclusively. Therefore, the present invention is
An object of the present invention is to provide a production system design support device capable of reliably designing an optimal production system in a short time without requiring many experts.

[0006]

The present invention is directed to a production condition base in which production condition data such as a production order of products to be manufactured is stored, and a process condition base in which process condition data such as the number of equipments in a production line is stored. A process simulation means for receiving the production condition data and the process condition data and simulating the operation of the equipment in the production line to obtain a simulation result such as an operation rate; and an evaluation index base in which a target index for the simulation result is stored. Evaluate whether the simulation result satisfies the target index. If the simulation result does not satisfy the target index based on this evaluation result, the production condition data stored in the production condition base according to the predetermined change condition. And change the process condition data stored in the process condition base A production system design support apparatus to be achieved the above object and a condition optimizing means that.

[0007]

By providing such means, the production condition data of the production condition base and the process condition data of the process condition base are received, and the process simulation means performs the simulation of the operation of the equipment in the production line to obtain the operation rate. Get the simulation result of. And
The condition optimization means evaluates whether or not the simulation result satisfies the target index. If the simulation result does not satisfy the target index based on this evaluation result, it is stored in the production condition base according to a predetermined change condition. The production condition data and the process condition data stored in the process condition base are changed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a production system design support apparatus. A production condition base 2, a process condition base 3 and a status base 4 are connected to the process simulator 1. As shown in FIG. 2, the production condition base 2 stores production condition data such as the production sequence, the number of productions, and the delivery date of each product type A, B, ...

The process condition base 3 stores the number of production line facilities, their capabilities, line configurations, operators, and the like. For example, the production line shown in FIG. 3 will be explained.
4 is arranged in parallel, and the equipment P5 is arranged on the output side of the equipment P2 to P4 via the buffer B1. In such a production line, the following data are given as process conditions. The production condition data and the transmission condition data are given to the work W1 input to the equipment P1. Each equipment P
1 to P5 are each provided with data relating to the capacity of the equipment. For example, the machining time, the setup time, and the setup time for each workpiece W1
The equipment failure rate, the time required for repairs in the event of failure, and the planned downtime are given. Further, the buffer B1 is provided with storage allowable values and initial values for each work W1. To the worker Q, the facilities P1 to P5 in charge, the work contents, the skill of the worker, and the like are given.

The process simulator 1 receives the production condition data stored in the production condition base 2 and the process condition data stored in the process condition base 3 and simulates the movements of the respective equipments P1 to P5 in the production line. It has the function of obtaining simulation results such as operating rates. Here, the simulation expresses the operation of each of the facilities P1 to P5 and the like by using each constituent element as shown in FIG. There is. Place "○"
Indicates the state, for example, equipment P1 to P5, buffer B1,
It is used for expressions such as loading and conveyance of the work W. The transition “|” indicates an operation, and is used to represent, for example, the connection state of processes. The arc “→” indicates the relationship between the state and the action, and is used for expressing the work W1 and the direction of information flow, for example. The token “●” indicates that the state is established in the place, and is used for expressing the work W1 and information.

For example, FIG. 4 shows a simulation model for a production line in which three equipments connected in parallel and two equipments connected in parallel are connected. In this model, each facility is represented by each place "○" and its connection is represented by the transition "|". Then, the processing time, which is the process condition data, is given to these places “◯”.

With such a configuration, FIG. 1A to FIG.
As shown in, the token "●" indicating the work is sequentially put into the three places "○", and when the given machining time elapses after the putting into these places "○" is completed, each of the placed tokens "○" ● "disappears, and two places" ○ "are placed through the transition" | "as shown in Fig. 6 (d).
Move to. Then, the token “●” is sequentially put into the three places “◯” again, and the same operation as above is performed. In addition, each place "○" does not output the token "●" input according to the given failure rate. In this case, the work at this time is a defective product.

By operating the simulation model, the process simulator 1 sequentially outputs the equipment status as a simulation result in units of time when the status changes, and stores it in the status base 4. This equipment status is waiting for work, arrival,
Waiting for process, defect occurrence, failure occurrence, ... Completion of processing, waiting for delivery to the next process, as shown in FIG.
~ P5 and stored for each work.

Explaining these equipment statuses, there is a "work waiting" waiting for the arrival of a work from the viewpoint of equipment, and a "process waiting" waiting for an empty process after the work arrives. When it is released, a defect occurs due to the given process conditions, resulting in “defect occurrence”. After this, a "fault occurrence" occurs, and a "worker wait" for performing the repair occurs. When this is released, the worker first performs "repair". Next, "setup occurrence" occurs each time the type of work changes, and "worker wait" for performing the setup occurs. When this is released, "setup" is performed for the first time.
Workers do. At this time, when the “setup” does not require a worker, for example, in the case of automatic setup, “waiting for worker” does not occur. The work that arrives after these steps is processed for the first time. When a worker is required for this processing, "waiting for the worker" occurs, and then "processing" actually occurs. The work that has been machined is "machined" and waits for the next process to become empty "waiting for delivery to the next process".

Therefore, the process simulator 1 calculates, from the equipment status, the cumulative number of products produced at a certain time, the number of products in progress, the cumulative number of defects, the cumulative operation rate as the operation status, the operation breakdown for each status, the lead time between steps, and the like.

A condition optimizing unit 5 is also provided, and an evaluation index base 6 and a knowledge base 7 are connected to the condition optimizing unit 5. Status base 4 for evaluation index base 6
A target index for the equipment status stored in is stored. Specifically, a plurality of evaluation indexes can be set as shown in FIG. 7, and the contents thereof are process, work, time, item, inequality sign, and value. Of these, the items are
The number of work in process, the number of defects, the operating rate, the status, the lead time, and the like, the inequality signs are “=”, “<”, “>”, etc., and the respective items relate the set values by the inequality sign. For example, in the above-mentioned index NO1, the expression “is the work W1 that is a certain process a at a certain time t1 and, for example, the number of products produced is greater than a certain value D?”

On the other hand, the knowledge base 7 describes two types of decision tables and IF THEN rules. As shown in FIG. 8, in the decision table, each evaluation index and each conditional expression are logical operators (logical sum, logical product, exclusive logical sum,
Inverse logical product, inverse logical sum, etc.) are related, and the change formula when this condition is satisfied is described. The conditional expression is described as an expression combining a plurality of conditions, that is, a process, a work, a time, an item, an inequality sign, and a value. In addition,
This change formula is for changing the production condition data and the process condition data. Therefore, FIG. 8 is expressed as “if the evaluation condition, the logical operator, and the conditional expression of the status are true, the contents described in the change expression are executed”.

FIG. 9 shows a modification formula table formed in the decision table. The modification formula table is composed of steps, modification categories, works, items and values. For example, it is expressed as “correcting, for example, a processing time of a work which is a certain process”.

On the other hand, the IF THEN rule is described by <conditional statement>, and this <conditional statement> is if (<expression 1><logicaloperator>, ...) then <conditional statement> or <expression 2> else <condition. Sentence> or <expression 2>.

<Formula 1> is for judging the condition of the evaluation index and the status. In the case of the evaluation index, it is composed of a process, a work, a time, an item, an inequality sign, and a value, and its expression is, for example, “a certain process. At a certain time of the work, for example, is the production number larger than a certain value? " In the case of status, it is composed of process, work, time, status, inequality sign, and value.

<Expression 2> is for changing the production condition or process condition, and is composed of a process, a change classification, a work, an item, and a value, and its expression is, for example, “a work of a certain process, for example, machining. Correct the time. "

The condition optimizing unit 5 inputs the equipment status and the evaluation index, and compares the equipment status and the evaluation index according to each condition described in the decision table or the IF THEN rule to determine the production condition and the process condition. It has a function to change and set. In this case, in order to optimally set these production conditions and process conditions, the condition optimization unit 5
Has a function of evaluating the evaluation index for the equipment status and automatically changing the priority of the IF THEN rule stored in the knowledge base 7 to approach the set evaluation index. Next, the operation of the apparatus configured as described above will be described with reference to the schematic diagram of condition optimization shown in FIG.

The process simulator 1 receives the production condition data stored in the production condition base 2 and the process condition data stored in the process condition base 3, and each place of the simulation model corresponding to the production line shown in FIG. Give process conditions such as processing time to "○" and token "●". Next, the process simulator 1 inputs a token "●" representing a work into the simulation model to operate the simulation model. The process simulator 1 while the simulation model is operating
Indicates the equipment status such as waiting for work, arrival, waiting for process, occurrence of failure, occurrence of machining, completion of machining, waiting for delivery to the next process, etc., and sequentially outputs them in the status base 4 in units of time when the state changes. .. Then, the process simulator 1 uses the facility statuses stored in the status base 4 to calculate the cumulative production number, the number of work in progress, the cumulative number of defects at a certain time, the cumulative operation rate as the operation status, the operation breakdown for each status, and the lead time between steps. Etc. are calculated.

The condition optimizing unit 5 inputs the equipment status stored in the status base 4 and the evaluation index stored in the evaluation index base 6, and each condition described in the decision table of the knowledge base 7 or IF The production status and process conditions are changed and set by comparing and judging the equipment status and the evaluation index according to THEN rules.

For example, when each condition described in the decision table is used, the condition optimizing section 5 reads out the process, work, time, item, inequality sign, and value from the evaluation index base 6 and, for example, indicates that the index NO1 is "present". At a certain time t1 of the work W1 which is the process a, for example, is the number of productions larger than a certain value D? As a result of this processing, if the number of products produced is larger than a certain value D, the condition optimizing unit 5 reads out the process, the change classification, the work, the item, and the value from the change formula table, and reads, for example, “a work of a certain process, for example, Correct the machining time ". That is, the condition optimizing unit 5 corrects the machining time stored in the process condition table 3.

On the other hand, when the IF THEN rule is used, the condition optimizing unit 5 reads out the process, the work, the time, the item, the inequality sign, and the value in the case of the evaluation index, and, for example, "at a certain time of the work that is a certain process. , For example, is the production number greater than a certain value? " As a result of this processing, if the number of products produced is larger than a certain value D, the condition optimizing unit 5 reads out the process, change classification, work, item, and value and, for example, “corrects, for example, the machining time of a work as a certain process. Execute.

As described above, in the above-described one embodiment, the production condition data and the process condition data are received, the movement of each facility in the production line is simulated, and the simulation result such as the operation rate is obtained. If the simulation result is not satisfied with the target index by evaluating whether the index is satisfied, the production condition data and process condition data are changed according to the changing conditions. Even if you are inexperienced without needing a lot of homes,
The optimal production system can be reliably designed in a short time. The present invention is not limited to the above-described embodiment, and may be modified within the scope of the invention.

[0029]

As described above in detail, according to the present invention, it is possible to provide a production system design support device which can surely design an optimum production system in a short time without requiring many experts.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a production system design support device according to the present invention.

FIG. 2 is a schematic diagram of production condition data in the same device.

FIG. 3 is a schematic diagram of process condition data in the same apparatus.

FIG. 4 is a diagram showing movements of components used for simulation of the apparatus.

FIG. 5 is a diagram showing an equipment status obtained by a simulation of the device.

FIG. 6 is a schematic diagram of a status base in the same device.

FIG. 7 is a schematic diagram of an evaluation index base in the device.

FIG. 8 is a schematic diagram of a decision table in the same device.

FIG. 9 is a schematic diagram of a change-type table in a decision table in the same device.

FIG. 10 is a view showing an operation of optimizing conditions in the device.

[Explanation of symbols]

1 ... Process simulator, 2 ... Production condition base, 3 ... Process base, 4 ... Status base, 5 ... Condition optimization unit, 6
… Evaluation index base, 7… Knowledge base.

Claims (1)

[Claims] 1. A production condition base in which production condition data such as a production order of products to be manufactured is stored, a process condition base in which process condition data such as the number of equipments in a production line is stored, the production condition data and the Process simulation means for receiving the process condition data and simulating the operation of the equipment in the production line to obtain a simulation result such as an operating rate, an evaluation index base in which a target index for the simulation result is stored, and the simulation result Is satisfied with respect to the target index, and if the simulation result is not satisfied with respect to the target index based on this evaluation result, the production stored in the production condition base in accordance with a predetermined change condition. The condition data and the work stored in the process condition base A production system design support device, comprising: a condition optimization means for changing condition data.