JP4754934B2 - Production plan creation device, production plan creation method, and program - Google Patents

Description

  The present invention relates to a production plan creation device, a production plan creation method, and a program for optimizing the production amount of each kind when producing a plurality of kinds of products in a multi-step production process such as a factory.

  2. Description of the Related Art Conventionally, in a production process composed of multiple steps represented by a material processing system production process such as steel, aluminum and copper, products of a plurality of types are often produced. And in order to increase profits as a company while adapting to the diversified customer needs in recent years, in addition to the cost reduction by the conventional operation improvement, the product composition (product mix) to be produced, that is, the production of each product By optimizing the amount, it is necessary to make effective use of limited production resources (equipment, etc.) and maximize profits. Moreover, in the multi-process / multi-product type production process, the range of production required for each product type (the lower limit production amount lower limit value / the upper production amount upper limit value), the facility capacity of each facility, and the production It is required to determine an optimum variety configuration while considering conditions such as the degree of freedom of the route (passing process route).

  In a multi-process production process, when manufacturing multiple types of products, there are multiple process designs, such as when there are multiple steps to produce one type of product or when there are alternative equipment. Even in this case, as a technique for optimizing the production amount of each type, for example, there is a technique disclosed in Patent Document 1.

  In the technique shown in Patent Document 1, based on manufacturing route information stored in advance (including alternative manufacturing route information if alternative equipment exists), the equipment load intensity and generation for each equipment for each process design Based on the variable costs, refer to the generated cost unit for each process design and the production volume information, raw material / sale price information, equipment information, and evaluation index registered in advance, and use the linear programming method to solve the optimization problem. By solving, the production volume for each process design is determined. In other words, the constraint that the total load of each equipment calculated from the processing capacity is within the range that does not exceed the equipment capacity (within the equipment capacity of each equipment), and the production volume of each process design is the minimum production quantity and the maximum production quantity. The production amount for each process design is determined so that the preset evaluation index is maximized while satisfying the restriction of being within the range of.

JP 2005-258788 A

  Here, at actual production technology sites, in order to be able to deal with forecast errors due to actual demand fluctuations from demand forecasts and short delivery orders such as express orders, an appropriate amount is required in the intermediate process in the middle of the production process. There is a request to prepare an in-process inventory amount. However, in the prior art, in order to optimize the production amount of each product type after the end of the final process, the in-process inventory amount in the intermediate process of the manufacturing process is not considered, and such a request is not met. It was. Further, in the prior art, the in-process inventory amount is treated as a cost in order to maximize the profit, and has been optimized to minimize the in-process inventory amount. That is, in the prior art, there is a possibility that an appropriate production plan cannot be obtained because the in-process inventory amount is not taken into consideration.

  The present invention has been made in view of the above-mentioned problems, and when manufacturing a plurality of types of products in a multi-process production process, each product is considered in consideration of an appropriate amount of in-process inventory in an intermediate process. The present invention provides a production plan creation device, a production plan creation method, and a program capable of obtaining a more appropriate production plan by optimizing the production amount of a product type.

Means and effects for solving the problems

In order to solve the above problems, a production plan creation device according to the present invention is a production plan creation device that optimizes the production amount of a plurality of types of products produced in a plurality of processes in a computer having a CPU and a storage device. The storage device stores a span that is a minimum time unit for evaluating constraints, a term that is composed of one or more spans and is a unit for producing a production plan, and a number of terms for producing the production plan. The term / span information setting means and one or more manufacturing routes to which equipment that can be processed for a plurality of processes for manufacturing a product are assigned for each product type are registered as a process design. Manufacturing route information storage means for registering the processing capacity of the process, equipment information storage means for registering equipment capacity for each term of each equipment, and for each term of each product type Production amount information storage means for registering the usable process design number, production amount lower limit value, and production amount upper limit value as the required production amount range, and for each of the types or each of the process designs, the predetermined amount Appropriate in-process inventory that is registered in such a manner that the appropriate range of the in-process inventory amount of the intermediate process in the span or the term is all the same in the predetermined span or the term, or is changed according to the predetermined span or the term. Quantity storage means, and the CPU is processing time in each process for each process design required to produce a unit quantity based on the processing capability of each process stored in the manufacturing route storage means. Means a process load basic unit calculating means for calculating a process load basic unit for each process for each process design, the process load basic unit calculated by the process load basic unit calculating means, A range of the production amount stored in the production information storage means, the equipment capacity stored in the equipment information storage means, and an appropriate range of the in-process inventory quantity in the intermediate process stored in the appropriate in-process inventory quantity storage means, Referring to each process for each of the process designs, the post-process has an amount of processing in the post-process at the time preceding the pre-process by the time required between the pre-process and the post-process. A constraint on the manufacturing amount of the preceding and following processes not exceeding the amount to be processed in the process, and a constraint on the facility capacity that the total load for each term of each facility determined by the processing capacity does not exceed the facility capacity; For each term of each of the varieties, the restrictions on the range of production amount that the total production amount of spans constituting the term is within the range between the production amount lower limit value and the production amount upper limit value, and the past From operation The in-process inventory amount of each intermediate process in the predetermined span or term for each product type or the process design in the predetermined span or term for each product type or the process design calculated based on the result is An optimum product configuration calculation means for calculating the production amount of each span of each process design that maximizes a preset evaluation index while satisfying the restrictions on the appropriate range of the in-process inventory amount that is determined to be an appropriate range. It is characterized by.

The production plan creation method according to the present invention is a production plan creation method executed by a production plan creation device that optimizes the production amount of a plurality of types of products produced in a plurality of processes in a computer having a CPU and a storage device. A term which is a unit of minimum time for evaluating constraints, a term which is composed of one or more spans and which is a unit of production plan creation, A process for a plurality of processes for manufacturing a product for each type by means of a term / span information setting step for storing the number of terms for which a plan is created, and a manufacturing route information storage means constituting the production plan creating device Register one or more manufacturing routes to which possible facilities are assigned as a process design, and register the processing capacity of each process for each process design. A facility information storage step for registering facility capacity for each term of each facility by a production route information storage step and facility information storage means constituting the production plan creation device, and production constituting the production plan creation device Production quantity information storage step for registering the usable process design number, production quantity lower limit value, and production quantity upper limit value as a range of required production quantity for each term of each type by means of quantity information storage means; by proper progress inventory amount storage means constituting the production plan creation device, for each design the breed or each said step, the proper range of the progress inventory of intermediate steps in a given the span or the term, the predetermined said all the same span or the term, or the proper progress inventory amount storage registers varied according to the predetermined the span or the term steps And each process design required to make a unit quantity of a product based on the processing capability of each process stored in the manufacturing route storage step by the process load basic unit calculation means constituting the production plan creation device. The process load unit calculation step for calculating the process load unit for each process for each process design, which means the processing time in each process, and the optimum product configuration calculation means constituting the production plan creation device, the process load unit. The process load basic unit calculated in the unit calculation step, the range of the production amount stored in the production amount information storage step, the facility capacity stored in the facility information storage step, and the appropriate in-process inventory amount storage step With reference to the appropriate range of the in-process inventory quantity of the intermediate process stored, for each process for each process design, the post process is a pre process relative to the pre process The amount of processing performed in the subsequent process at the time until the time required between the subsequent process and the subsequent process does not exceed the amount processed in the previous process, and the above-mentioned processing capacity The total load for each term of each facility does not exceed the facility capacity, and the total production amount of spans constituting the term for each term of each product type is the production lower limit. A predetermined span for each product type or each process design calculated on the basis of a result from a past operation and a restriction on a production amount range that is within a range within a production value upper limit value or more while satisfying the constraint on the proper range of the in-process inventory of progress inventory amount of each intermediate step in terms to said a proper range, each scan of each step design evaluation index previously set the maximum Characterized in that it comprises the optimal product mix calculation step of calculating the emissions production amount.

A program according to the present invention is a program executed by a production plan creation device for optimizing the production amount of a plurality of types of products produced in a plurality of processes in a computer having a storage device and a CPU, Creates a production plan by using a term / span information setting means that constitutes a production plan creation device, a span that is a unit of minimum time for evaluating constraints, a term that is composed of one or more spans and is a unit of production plan creation, and By means of a term / span information setting step for storing the number of terms, and a manufacturing route information storage means constituting the production plan creation device, facilities that can be processed for a plurality of processes for manufacturing products for each product type are provided. One or more assigned manufacturing routes are registered as a process design, and the process capability for each process is registered for each process design. A facility information storing step for registering facility capacity for each term of each facility by a route information storing step and facility information storing means configuring the production plan creating device, and a production amount constituting the production plan creating device Production amount information storage step for registering the usable process design number, the production amount lower limit value, and the production amount upper limit value as a range of the required production amount for each term of each type by the information storage means, by proper progress inventory amount storage means constituting the production plan creation device, for each design the breed or each said step, the proper range of the progress inventory of intermediate steps in a given the span or the term, the predetermined said span or all the same for the term or the proper progress inventory storage step of registering the predetermined the span or correspondingly by changing the term Each process design required to make a unit quantity of a product based on the processing capability of each process stored in the manufacturing route storage step by the process load basic unit calculation means constituting the production plan creation device. The process load basic unit calculation by the process load basic unit calculation step for calculating the process load basic unit for each process for each process design, which means the processing time in the process, and the optimum product configuration calculation means constituting the production plan creation device The process load basic unit calculated in the step, the range of the production volume stored in the production volume information storage step, the facility capacity stored in the facility information storage step, and the proper in-process inventory quantity storage step With reference to the appropriate range of the in-process inventory amount of the intermediate process, for each process for each process design, the post process is the same as the previous process and the post process. Restrictions on the manufacturing amount of the preceding and following steps that the amount processed in the subsequent step does not exceed the amount processed in the previous step at the time before the required inter-step time required between the steps, and each of the above-mentioned obtained by the processing capability Restriction on facility capacity that the total load of each term of the facility does not exceed the facility capacity, and the total production amount of spans constituting the term is greater than or equal to the production amount lower limit value for each term of each type In the predetermined span or term for each product type or each process design calculated based on the constraints on the range of the production amount to be within the upper limit of the production amount and the results from the past operation while satisfying the constraint on the proper range of the in-process inventory of progress inventory amount of each intermediate step and said a proper range, each span of the process design of the evaluation index set in advance is maximized And optimum product mix calculation step of calculating the production volume, provided with, and installed in the storage device, characterized in that it is performed by reading by the CPU.

According to this, for each process for each process design, the post-process is the amount of processing in the post-process at the time preceding the previous process by the time required between the pre-process and the post-process. Restrictions on the production volume of the pre- and post-processes that do not exceed the amount processed in the process, restrictions on the facility capacity that the total load of each equipment term determined by the processing capacity does not exceed the equipment capacity, and each term of each product type In addition to restrictions on the range of production that the total production volume of the span that constitutes the term is within the range of the production volume lower limit value and within the production volume upper limit value , the calculation is based on the results from past operations. suitable for progress inventory amount of the intermediate step, all the same at a predetermined span or term, or registered varied according to a predetermined span or terms in, predetermined span or term varieties or each step for each design While satisfying the constraint on the proper range of the in-process inventory amount to range, in a period (full term) to perform the production planning, evaluation index previously set is determined to be maximum. Therefore, when manufacturing multiple types of products in a multi-process production process, it is possible to optimize the production amount of each product while providing an in-process inventory within the appropriate range in the intermediate process. A production plan can be created.
Here, “equipment capacity” of each facility means, for example, time (operating rate, etc.) that can be spent on net processing when the facility is operated to the maximum. “Processing capacity” that can be processed in each process is an ability to process a product or an intermediate product in each process. For example, a product or an intermediate product that can be processed per predetermined time in each process. It means weight. The "total load for each term of each facility" obtained from the processing capacity is the total load for each term of the actual processing in each facility. For example, in order to produce products in each facility This means the total required processing time for each term, and is calculated based on processing capacity.

Here, in the production plan creation device according to the present invention, the optimum product configuration calculation means has an in-process inventory amount of an intermediate process in the predetermined span or term for each product or each process design within the appropriate range. In addition to adding a variable corresponding to the deviation from the appropriate range of the in-process inventory amount of the intermediate process in the predetermined span or term for each product type or each process design, and to the evaluation index On the other hand, the variable may be added as a penalty to calculate the production amount of each span of each process design that maximizes a preset evaluation index that satisfies the constraint.
Similarly, in the production plan creation method according to the present invention, the optimum product configuration calculation step is such that the in-process inventory amount of the intermediate process in the predetermined span or term for each product or each process design is within the appropriate range. In addition to adding a variable corresponding to the deviation from the appropriate range of the in-process inventory amount of the intermediate process in the predetermined span or term for each product type or each process design, and to the evaluation index On the other hand, the variable may be added as a penalty to calculate the production amount of each span of each process design that maximizes a preset evaluation index that satisfies the constraints.
Similarly, in the program according to the present invention, the optimum product configuration calculation step is subject to the restriction that the in-process inventory amount of the intermediate process in the predetermined span or term for each product or process design is within the appropriate range. On the other hand, a variable corresponding to the deviation amount from the appropriate range of the in-process inventory quantity of the intermediate process in the predetermined span or the term for each product type or each process design is added, and for the evaluation index A variable may be added as a penalty to calculate the production amount of each span of each process design that maximizes a preset evaluation index that satisfies the constraints.
According to this, in contrast to the restriction that the in-process inventory amount in the intermediate process in the predetermined span or term for each product type or process design is within the appropriate range, the intermediate process in the predetermined span or term for each product type or process design. A variable corresponding to the deviation amount from the appropriate range of the in-process inventory amount is added, and the variable is added as a penalty to the evaluation index. Therefore, even if there is no solution that satisfies the constraint that the in-process inventory amount in the intermediate process is within the appropriate range, the solution can be obtained reliably, avoiding the result without solution, and deviating from the appropriate range of the in-process inventory amount. A solution that minimizes the quantity is given priority.

  Here, the production plan creation device, the production plan creation method, and the program according to the present invention preferably perform the calculation of the evaluation index by a linear programming method.
  According to this, when the production volume for each process design and the load of each facility necessary for the production by the process design can be handled in a linear format, linear programming can be applied to the calculation of the evaluation index. Therefore, even when the number of varieties and facilities is large, the production amount for each process design can be optimized at high speed.

また、本発明に係る生産計画作成装置は、前記適正仕掛在庫量記憶手段は、複数の前記中間工程を合わせて大括りにした過程において中間製品状態を定義し、当該中間製品単位での前記スパン毎の仕掛在庫量の適正範囲を登録し、前記最適品種構成計算手段は、前記中間製品単位での仕掛在庫量を計算して良い。同様に、本発明に係る生産計画作成方法及びプログラムは、前記適正仕掛在庫量記憶ステップは、複数の前記中間工程を合わせて大括りにした過程において中間製品状態を定義し、当該中間製品単位での前記スパン毎の仕掛在庫量の適正範囲を登録し、前記最適品種構成計算ステップは、前記中間製品単位での仕掛在庫量を計算して良い。
また、本発明に係る生産計画作成装置は、前記最適品種構成計算手段は、定義された前記中間製品に分類するための定数Ｌｉｋｎを用いた数２に示す次式、または、数３に示す次式に基づいて、前記中間製品単位の仕掛在庫量を線形計画法により計算して良い。同様に、本発明に係る生産計画作成方法及びプログラムは、前記最適品種構成計算ステップは、定義された前記中間製品に分類するための定数Ｌｉｋｎを用いた数２に示す次式、または、数３に示す次式に基づいて、前記中間製品単位の仕掛在庫量を線形計画法により計算して良い。

これにより、中間製品の仕掛在庫量を具体的に計算することができる。 Here, the production plan creation device according to the present invention, the optimum product mix calculation means, based on the following formula shown in Equation 1, may Widgets inventory of the intermediate step were calculated by linear programming. Likewise, production planning method and program according to the present invention, the optimum product mix calculating step, based on the following equation shown in Equation 1, may Widgets inventory of the intermediate step were calculated by linear programming.

Moreover, the production plan creation device according to the present invention, the proper progress inventory amount storage means, together a plurality of said intermediate step to define an intermediate product state in the process that the large enclosed, the span in the intermediate product unit An appropriate range of the in-process inventory amount for each product may be registered, and the optimum product configuration calculating unit may calculate the in-process inventory amount for each intermediate product . Likewise, production planning method and program according to the present invention, the proper progress inventory amount storing step, together a plurality of said intermediate step to define an intermediate product state in the process that the large enclosed, in the intermediate product unit The appropriate range of the in-process inventory amount for each span may be registered, and the optimum product configuration calculation step may calculate the in-process inventory amount for each intermediate product .
Further, in the production plan creation device according to the present invention, the optimum product configuration calculating means uses the constant Likn for classifying the defined intermediate product, or the following equation shown in Equation 2 or based on the equation, may widgets inventory of the intermediate product unit was calculated by the linear programming. Similarly, in the production plan creation method and program according to the present invention, the optimum product configuration calculation step includes the following equation shown in Equation 2 using the constant Likn for classifying into the defined intermediate product, or Equation 3 based on the following formula shown in, may widgets inventory of the intermediate product unit was calculated by the linear programming.

Thereby, the in-process inventory amount of the intermediate product can be specifically calculated.

  Here, in the production plan creation device according to the present invention, the optimum product configuration calculation means may set the evaluation index based on the production amount maximization. Similarly, in the production plan creation method and program according to the present invention, the optimal product type composition calculation step may set the evaluation index based on the production amount maximization. This case can be applied when the purpose is to maximize production.

  Here, in the production plan creation device according to the present invention, the storage device is a product information storage means for storing raw material costs and selling prices for each of the types, and a cost that is incurred for processing the unit amount in each step. Generated cost information storage means for storing a variable cost, and the CPU generates the unit amount of the product based on the variable cost stored in the generated cost information storage means The generated cost basic unit calculating means for calculating the generated cost basic unit for each process design, which means the cost for each process design, and the optimum product configuration calculating means is calculated by the generated cost basic unit calculating means. The evaluation index may be set on the basis of profit maximization or profit or production weight weight with reference to the generated cost basic unit, the raw material cost stored in the product information storage means, and the selling price. Similarly, the production plan creation method and program according to the present invention include a product information storage step for storing raw material costs and selling prices for each product type by means of product information storage means constituting the production plan creation device, and the production A generated cost information storage step for storing a variable cost, which is a cost generated to process a unit amount in each process, by an generated cost information storage means constituting the plan creation device, and an generated cost constituting the production plan creation device Based on the variable cost stored in the generated cost information storage step by the basic unit calculation means, the generated cost source for each process design means the cost for each process design generated to make a unit quantity of a product. A cost generation unit calculation step for calculating a unit, and the optimum product configuration calculation step is calculated in the cost generation unit calculation step. The evaluation index may be set based on profit maximization or profit or weight sum of production amount with reference to the generated cost basic unit, the raw material cost stored in the product information storing step, and the selling price. . This case can be applied when the purpose is to maximize profits. Further, when the profit is maximized while securing the production volume or the profit is the same, the evaluation index can be applied as a weighted sum of the profit and the production volume when a product configuration with a large production volume is desirable.

  In the production plan creation device according to the present invention, the storage device further includes product information storage means for storing a selling price for each product, and the optimum product configuration calculation means is the generated cost unit calculation means. The evaluation index may be set based on the total sales maximization with reference to the calculated generated cost basic unit, the raw material cost stored in the product information storage unit, and the selling price. Similarly, the production plan creation method and program according to the present invention further comprises a product information storage step for storing a selling price for each product type by means of product information storage means constituting the production plan creation device, and the optimum The product type composition calculation step refers to the generated cost basic unit calculated in the generated cost basic unit calculation step, the raw material cost and the selling price stored in the product information storage step, and is based on maximization of total sales. The evaluation index may be set.
  In this case, it can be applied when it is desired to determine a variety configuration that places more importance on the total deposit than profit.

  The program according to the present invention can be recorded and distributed on a removable recording medium such as a CD-ROM (Compact Disc Read Only Memory) and DVD (Digital Versatile Disk) and a fixed recording medium such as a hard disk. Distribution is possible via a communication network such as the Internet by wired or wireless telecommunication means.

  Hereinafter, the best mode for carrying out a production plan creation device, a production plan creation method, and a program according to the present invention will be described based on a specific example with reference to the drawings.

First, an example of a production line targeted in the present embodiment will be described with reference to FIG. FIG. 3 is a diagram showing a production line.
As shown in FIG. 3, the production line from the raw material 100 to the product 160 includes melting (melting 01 and melting 02) 110, hot rolling 120, cold rolling (cold rolling 01, cold rolling 02 and cold rolling 03) 130. , Sinter (sintered 01 and sinter 02) 140 and slitter (slitter 01, slitter 02 and slitter 03) 150, except for hot rolling 120, is composed of a plurality of facilities having different capacities. Here, it is assumed that the equipment used and the order differ depending on the type (product type) of the product, and the arrows in the figure indicate the manufacturing routes (the individual routes will be described later based on Table 3).

  Further, the “operating rate” of each term shown in Table 1 is defined as the equipment capacity of each equipment. Here, the operation rate is a ratio of time that can be spent for net processing when the facility is operated to the maximum, and is set statistically from the operation results of the facility. For example, if the operation rate is 80%, it means that 19.2 hours can be spent for net processing in the day, and the remaining time is consumed for work preparation and maintenance.

  In this embodiment, the term length is 30 days (one month) and the span length is 5 days. In the present embodiment, the period for creating the production plan is 3 terms (about 3 months). In consideration of the fact that the load on the equipment in the first term and the final term is smaller than in other terms, in this embodiment, the term having the same information as the first term is placed before the first term, after the last term. The calculation was performed by adding each term with the same information as the final term.

Next, Table 2 shows a product type table used in this embodiment.
As shown in Table 2, there are five types of “types” from A to E, and there are two to three types of production routes as “process design” of each type. For example, in the type C, there are three types of process designs with process design numbers 5 to 7.
In addition, as shown in Table 2, each variety produces a production amount required within each term, that is, a lower limit amount to be produced within each term (“production amount lower limit value”) and beyond. However, there is an upper limit amount ("production amount upper limit value") that cannot be sold or stored. Therefore, it is necessary to perform production within a range between the production lower limit value and the production quantity upper limit value using any given process design.
Furthermore, as shown in Table 2, “raw material cost” and “selling price” per ton are given. In the present embodiment, the raw material cost can be set to a different value for each process design.

Next, Table 3 shows a passing process table of each process design used in the present embodiment. Here, in the passing process table, the manufacturing route in each “process design” for each “product type” is shown, and the intermediate product is manufactured through the processes in the order of “process serial number” shown in Table 3. Finally, products of each variety are manufactured. In each step, as shown in Table 3, “facility” that can be processed is assigned.
As shown in Table 3, the weight of a product or an intermediate product that can be processed per hour in each process is defined as “load” (processing capacity) in each process. For example, the type A of the process design number 1 can be processed by 30.0 tons per hour in the melting 01 that is the equipment of the process number 1.
In addition, the cost incurred for processing 1 ton in each process is defined as “variable cost”. For example, in order to process 1 ton of product type A with process design number 1, a variable cost of 45,000 yen is required for melting 01, which is a process number 1 facility.
In addition, the weight cost on the exit and entry sides of the equipment is defined as “process yield”. For example, in the melting 01 that is the equipment of the process number 1, in order to complete 99 tons of the product A of the process design number 1, it is necessary to input 100 tons. One ton is discarded as a defective part at the front and rear ends.

Next, a production plan creation device, a production plan creation method, and a program according to the present embodiment will be described. First, a production plan creation device that executes a production plan creation method according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram of a production plan creation apparatus according to the present embodiment.
As shown in FIG. 1, a production plan creation apparatus 1 includes a production amount information storage unit (production amount information storage unit) 2, a raw material / sale price information storage unit (product information storage unit) 3, and an equipment information storage unit (equipment). Information storage means) 4, evaluation index setting section 5, term / span information setting section (term / span information setting means) 6, proper in-process inventory storage section (appropriate in-process inventory storage means) 7, and process load intensity Calculation unit (process load basic unit calculation means) 10, manufacturing route information storage unit (production route information storage unit) 11, generated cost basic unit calculation unit (generated cost basic unit calculation unit) 20, and generated cost information storage unit (Occurrence cost information storage means) 21, an optimum product configuration calculation unit (optimum product configuration calculation unit) 30, and a result output unit 40. In the production plan creation device 1, these pieces of information input from an input unit (keyboard or the like) (not shown) are stored in an external storage device (auxiliary storage) such as a ROM (Read Only Memory), a RAM (Random Access Memory), or a hard disk. Device) or the like, executed by a CPU (Central Processing Unit) or the like, and output to an output device (display or the like).

  The production amount information storage unit 2 is for storing information on the process design number, production lower limit value, and production upper limit value that can be used for each product type. In the present embodiment, this corresponds to the columns of “process design number”, “production amount lower limit value”, and “production amount upper limit value” in the type table of Table 2 described above.

  The raw material / selling price information storage unit 3 is for storing information on the raw material cost and selling price for each product type. In the present embodiment, this corresponds to the columns of “raw material cost” and “selling price” in the type table of Table 2 described above. In the present embodiment, the raw material cost is set for each process design, and the raw material cost varies depending on the process design in all types of product types A to E.

  The facility information storage unit 4 is for storing information related to the facility capability of each facility. In this embodiment, it corresponds to the column of “operation rate” in the equipment table of Table 1 described above.

  The evaluation index setting unit 5 is for setting an evaluation index serving as a reference for optimizing the production amount of each product type. In this embodiment, the total profit, which is the sum of (sales price−raw material cost−variable cost), is used as the evaluation index.

  The term / span information setting unit 6 is for setting information on the length of the term, the length of the span, and the period for creating the production plan. In this embodiment, the term length is 30 days (one month) and the span length is 5 days. In the present embodiment, the period for creating the production plan is 3 terms (about 3 months).

The manufacturing route storage unit 11 is for storing the equipment used and the order of use for each process design, and the processing capability of each process for each process design.
In the present embodiment, it corresponds to the column of “equipment” and “load” in “process serial number” in the above-described passing process table of Table 3.

  Based on the processing capability of each process stored in the manufacturing route storage unit 11, the process load basic unit calculation unit 10 is a process load basic unit for each process (process design required to make one ton of product). It means the processing time in each process for every step). The calculation method of the process load basic unit for each process for each process design in the present embodiment will be described below using Table 4.

In the present embodiment, first, for each process design number, in order from the process having the largest process number (final process), the equipment output in each process when producing 1 ton of product based on the “process yield”. Calculate the side weight (defined as “reference weight”). In the first step, the weight of the necessary raw material (defined as “necessary raw material”) is calculated. The calculation results are shown in Table 4 below.
As shown in Table 4, for example, in the cold rolling 02 that is the equipment of the process number 5 of the process design number 1, the reference weight is obtained by using the process yield in the slitter 03 that is the equipment of the process number 6. 1 [ton] /0.9=1.11.111111. Further, in the slitter 01 which is the equipment of the process serial number 4, the reference weight is 1.111111111 ... [ton] / ton using the process yield and load of the cold rolling 02 which is the equipment of the process serial number 5. 0.98 = 1.13378685 ... [tons]. Similarly, the reference weight is calculated up to the process number 1 (step 1). Then, using the reference weight and the process yield of the process number 1 (first process), the necessary raw material for producing 1 ton of product is calculated. For example, in the process design number 1, the necessary raw material is 1.42900859... [Tons] /0.99=1.444344302.

Next, based on the “reference weight” and “load” in each process, the processing time (defined as “reference time”) in each process when producing 1 ton of product is calculated. Table 4 shows the calculation results.
As shown in Table 4, for example, in the cold rolling 01 which is the equipment of the process number 3 of the process design number 1, the reference time is 1.28839415... [Ton] /60.0 [ton / hr] = 0.021473236 ... [hr].

  The generated cost information storage unit 21 is for storing a cost generated for processing 1 ton in each process, that is, a variable cost. In the present embodiment, this corresponds to the “variable cost” column in the passage process table of Table 3 described above.

  Based on the variable cost stored in the generated cost information storage unit 11, the generated cost basic unit calculation unit 20 generates the generated cost basic unit for each process design (the cost for each process design generated to make one ton of product). Means). The calculation method of the generated cost basic unit for each process design in this embodiment will be described below using Tables 4 and 5.

In the present embodiment, first, when one ton of product is produced based on the “variable cost” stored in the generated cost information storage unit 21 and the “reference time” calculated by the process load basic unit calculation unit 10. The cost (defined as “standard cost”) generated in each process is calculated. Here, the weight on the entry side of each facility is used as the reference weight. Table 4 shows the calculation results.
As shown in Table 4, for example, in the process design number 2, in the hot rolling which is the equipment of the process serial number 2, the standard cost is 210 [thousands based on the variable cost of hot rolling and the standard time of hot rolling. Yen / hr] × 0.021473236... [Tons] = 4.509379509... [1000 yen].

  Next, the calculated reference costs for each process are tabulated for each process design number, and the generated cost basic unit for each process design is calculated. Table 5 shows the calculation results.

  The appropriate in-process inventory storage unit 7 is for registering the appropriate range of the in-process inventory amount of the intermediate process in a predetermined span or a predetermined term for each product type or each process design. Here, the inventory in the intermediate process of each product type in each span will be considered, but it is not realistic to manage the in-process inventory amount by individual process design or detailed process design defined in the actual factory. Absent. Therefore, in the present embodiment, an intermediate product state is defined in a process in which a plurality of processes are combined, and an appropriate range of the in-process inventory amount for each span in the intermediate product unit is considered. The appropriate range of the in-process inventory amount is the same for all spans. Specifically, for example, as shown in FIG. 4, when considering product type A consisting of two types of process designs, the intermediate product before entering the hot rolling process after melting is referred to as “slab” The intermediate product before the cold rolling after the rolling is finished can be treated as a “hot coil”, and the intermediate products in all the processes after the cold rolling can be collectively treated as a “cold coil”. In the actual production process, there are far more facilities than in this example, and the inventory of more processes can be collected by intermediate products. In this embodiment, the upper and lower limits of the in-process inventory amount of intermediate products are set for every span of each product type. However, there is a problem that the number of constraint equations for linear programming increases and the problem scale increases. In some cases, for example, the upper and lower limit values are set only at a specific point in time, such as setting the upper and lower limit values of the in-process inventory amount for each term, or the upper and lower limit values are set only for the average value of the in-process inventory amount within the term. It is also possible to modify such as by providing.

  The optimum product configuration calculation unit 30 generates the generated cost basic unit for each process design calculated by the generated cost basic unit calculation unit 20 and the process load basic unit for each process for each process design calculated by the process load basic unit calculation unit 10. Production amount information stored in the production amount information storage unit 2, raw material / sale price information stored in the raw material / sale price information storage unit 3, facility information stored in the facility information storage unit 4, and setting in the evaluation index setting unit 5 With reference to the evaluation index and the appropriate range of the in-process inventory amount of the intermediate process in a predetermined span or predetermined term for each product type or process design stored in the appropriate in-process inventory storage unit 7, Evaluate while considering restrictions on the quantity range (above the lower limit of production volume and within the upper limit of production quantity), restrictions on the production volume of the preceding and following processes, and restrictions on the appropriate range of in-process inventory quantity (above the lower limit value and within the upper limit value) There determines the production amount for each process design that maximizes.

Here, a method for calculating the in-process inventory amount of the intermediate product is shown. First, let us consider the in-process inventory amount every moment before the process k manufactured in each process design i. Since the in-process inventory amount is a result from the past operation, assuming that the initial in-process inventory amount at the start of span 1 is Y _ik , the in-process inventory amount at the end of each span t is expressed by the following equation (1). It can be expressed as follows. Here, since the in-process inventory amount is all converted into the amount at the time when it becomes the final product, the conversion coefficient G _ik is applied, and the process is started at the previous step k ′ = k−1. As the stock of process k increases, the in-process stock quantity moves to the next process when processing of its own process is started. By adding the increase / decrease in each span to the initial in-process stock quantity, The amount of inventory in each process is calculated. However, although the inventory before the process 1 corresponds to the raw material inventory, k = 1 is not considered here.

In the present embodiment, considering the appropriate range (upper and lower limits) of the in-process inventory amount set for each span for each of the three types of intermediate products of “slab”, “hot coil”, and “cold coil” for each product type Therefore, when the in-process inventory quantity of each process design i and each process k of the formula shown in the above formula 1 is collected by each product type j and each intermediate product n, it can be expressed as the following formula 2. Here, a constant L _ikn for classifying the in-process inventory quantity before each process into intermediate products such as slabs, hot coils, and cold coils as shown in FIG. 4 is prepared, and each process design number i shown in _Equation 1 is prepared. The intermediate product of each product j after the end of each span is obtained by summing up the in-process inventory amount before the process k for the same intermediate product n and adding the in-process inventory amount of the process design number i belonging to the same product type. The in-process inventory quantity S _jnt (the quantity converted into the final product) for n is shown.

Note that the method of calculating the in-process inventory amount S _jnt for the intermediate product n of each product type j after the end of each span is not limited to the formula shown in Equation 2 above. For example, there is the following equation (3) as a simpler calculation method than the equation (2). In the equation shown in Equation 3, in the continuous process k classified as the same intermediate product n, even if the process moves, the intermediate product n does not change, and the entry and exit in such preceding and following steps is the equation shown in Equation 2. In this case, the addition and subtraction are omitted because they are added and subtracted. In other words, in the equation shown in Equation 3, in each process design i, the intermediate product n entry side process K ⁱⁿ _in (process that becomes intermediate product n by processing in this process) and the exit side process K ^out _in (in this process) Considering only the process of moving from intermediate product n to the next intermediate product due to processing, and summing only the amount that comes in and out as the intermediate product from the sum of the initial inventory values existing in that range Yes.

  In this way, since there are various management methods for the in-process inventory of intermediate products depending on the target factory, etc., the definition suitable for the target is not limited to the formulas shown in Equations 2 and 3 above. It is desirable to use it.

As described above, the in-process inventory amount of the intermediate product is defined. In the present embodiment, each span for each process design is obtained by solving the optimization problem of the following equation (4) using the equation (2) as the calculation of the in-process inventory quantity of the intermediate product and using the linear programming method. Determine the production volume. In the equation shown in Equation 4, the amount that is processed in the subsequent process does not exceed the amount that is processed in the previous process, and the total load for each term of each facility determined by the processing capacity does not exceed the facility capacity, In addition to the restriction that the total production volume of the span that constitutes the term is within the range between the production volume lower limit value and the production volume upper limit value for each product type term, the in-process inventory of intermediate products for each product type span The solution of the production volume of each span that maximizes the marginal profit can be obtained while satisfying the constraint that is within the proper range. In other words, in addition to the prior art, based on the appropriate ranges B _jn ^min and B _jn ^max of the in-process inventory quantity for each span for the intermediate product n of each product type j previously determined in the appropriate in-process inventory storage unit 7, The restriction regarding the in-process inventory amount that the in-process inventory amount S _jnt related to the intermediate product n of each type j after the end of each span shown in FIG. In the equation shown in Equation 4, in order to avoid that only a result without solution is obtained even when there is no solution satisfying the constraint condition, a variable ε representing the shortage / excess amount from the appropriate range of the in-process inventory amount. _jnt ^min and ε _jnt ^max are provided. By adding these variables as penalties with appropriate weights to the evaluation function, even if there is no solution to find the appropriate range of in-process inventory, the shortage and excess from the appropriate range of in-process inventory are minimized. Can always get the solution. It is also possible to obtain information such as how many kinds of intermediate products cannot satisfy the constraints.

The result output unit 40 is an output device (such as a display or a printer) for displaying the calculation result of the optimum product configuration calculation unit 30 via the output interface. As the calculation result, the optimized product configuration, the profit for the optimized product configuration, the load status of the equipment, and the like are output.
The output interface is a program or hardware for performing data conversion and communication for outputting the calculation result in the optimum product configuration calculation unit 30 to an output device (display or printer).

Next, the processing procedure of the production plan creation method executed by the production plan creation apparatus 1 according to the present embodiment will be described with reference to FIG. FIG. 2 is a flowchart illustrating the processing procedure of the production plan creation method according to the present embodiment.
Note that the processing of the production plan creation method according to the present embodiment described below can be similarly read and executed by the CPU as a program in a computer. Further, this program can be installed in various computer storage devices by recording it in a removable storage medium such as a CD-ROM or DVD.

As shown in FIG. 2, first, in advance, cost information for each process design, production route information, production volume information, raw material / sale price information, equipment information, evaluation index, term span information, and work in progress for intermediate processes Data on information relating to inventory is input, and the generated cost information storage unit 21 such as a magnetic storage device, the production route information storage unit 11, the production amount information storage unit 2, the raw material / sale price information storage unit 3, and the equipment information storage unit, respectively. 4. Registered in the evaluation index setting unit 5, the term / span information setting unit 6, and the appropriate in-process inventory quantity storage unit 7 (step S1: production quantity information storage step, product information storage step, equipment information storage step, (Term / span information setting step, generated cost information storage step, appropriate work-in-progress inventory storage step).
For details of this step, the generated cost information storage unit 21, the production route information storage unit 11, the production amount information storage unit 2, the raw material / sale price information storage unit 3, and the facility information storage unit of the production plan creation apparatus 1 described above. 4. The description is the same as the description of the evaluation index setting unit 5, the term / span information setting unit 6, and the in-process inventory quantity storage unit 7, and the description thereof is omitted.

Next, based on the manufacturing route information stored in the manufacturing route information storage unit 11, the process load unit calculation unit 10 calculates a process load unit for each process for each process design (step S2: process load). Basic unit calculation step).
Note that the details of this step are the same as those described in the process load intensity calculation unit 10 of the production plan creation apparatus 1 described above, and a description thereof will be omitted.

Further, based on the generated variable cost stored in the generated cost information storage unit 21 and the reference time calculated by the process load unit calculation unit 10, the generated cost unit calculation unit 20 generates the generated cost source for each process design. A unit is calculated (step S3: cost generation unit calculation step).
The details of this step are the same as those described in the generated cost basic unit calculation unit 20 of the production plan creation apparatus 1 described above, and a description thereof is omitted.

Then, in the optimum product configuration calculation unit 30, the generated cost basic unit calculated by the generated cost basic unit calculation unit 20, the process load basic unit calculated by the process load basic unit calculation unit 10, and the production amount information storage unit 2 in advance. , Raw material / sale price information storage unit 3, equipment information storage unit 4, evaluation index setting unit 5, term / span information setting unit 6, and proper in-process inventory quantity storage unit 7. , Equipment information, evaluation index, information on term span, and information on in-process inventory of intermediate processes, and determine the production volume for each process design by solving the optimization problem using linear programming (Step S4: Optimal product configuration calculation step).
The details of this step are the same as the description of the optimum product configuration calculation unit 30 of the production plan creation apparatus 1 described above, and a description thereof will be omitted.

Finally, the calculation result in the optimum product configuration calculation unit 30 is displayed on the output device (display or printer or the like) via the result output unit 40 (step S5).
The details of this step are the same as those described in the result output unit 40 of the production plan creation apparatus 1 described above, and a description thereof is omitted.

  Next, an example in which a production plan is actually created using a production plan creation device, a production plan creation method, and a program according to the present embodiment will be described.

  In this example, the optimum product type composition calculation unit 30 considers restrictions on the appropriate range of the in-process inventory quantity (lower limit value and within the upper limit value) for each term, and the appropriate in-process inventory quantity storage unit 7 determines for each product type. The appropriate range (upper and lower limits) of the in-process inventory is set for each term in the three types of intermediate products, “Slab”, “Hot Coil”, and “Cold Coil”. The appropriate range (upper and lower limit values) of the in-process inventory amount set in the appropriate in-process inventory amount storage unit 7 is shown in Table 6 below.

  In this example, the optimized variety configuration output in the result output unit 40 is shown in Tables 7 to 9 below. Table 7 shows the production amount in each term for each type. Table 8 shows the operation rate of each facility. Table 9 shows the in-process inventory amount at the end of each term for each intermediate product.

Here, for comparison, a case will be considered where the present invention is applied to a conventional technique for obtaining an optimum product type configuration without considering the in-process inventory amount. That is, without considering the restriction that the in-process inventory amount of the intermediate process in the predetermined span or term for each product type or process design is within the appropriate range, the amount processed in the subsequent process does not exceed the amount processed in the previous process, In addition, the total load for each term of each facility determined by the processing capacity does not exceed the facility capacity, and for each term of each product type, the total production volume of the span that constitutes the term is greater than the production lower limit value. Consider the case of applying to the prior art that finds the solution of the production volume of each span that maximizes the marginal profit while satisfying only the constraint that it is within the upper limit of the quantity. Specifically, using the linear programming method, the in-process inventory amount of intermediate products in each span of product types is within an appropriate range from the equation shown in Equation 4 for determining the production amount of each span for each process design in this embodiment. The optimization problem of the following equation (5) excluding variables ε _jnt ^min and ε _jnt ^max that represent the shortage and excess from the appropriate range of the in-process inventory amount provided as a penalty in the evaluation function To determine the production volume of each span for each process design.

  Table 10 to Table 12 below show the optimized variety configuration obtained based on the equation shown in Equation 5. Table 10 shows the production amount in each term for each type. Table 11 shows the operation rate of each facility. Table 12 shows the in-process inventory amount at the end of each term for each intermediate product. In this example using the present embodiment, since restrictions on the appropriate range of the in-process inventory amount (lower limit value and upper limit value) are considered for each term, the values of each term in Tables 10 to 12 are as follows. showed that.

  In the example using the conventional technology, it can be seen from the results of Tables 10 and 11 that the production amount of each type and the operating rate of each facility satisfy the restriction ranges set in Tables 1 and 2. On the other hand, the in-process inventory amount of each intermediate product that does not take restrictions into consideration fluctuates greatly as can be seen from Table 12, and it can be seen that the restriction range set in Table 6 is not satisfied. For example, the cold coil of product type B has an in-process inventory amount approaching zero at the end of term 2 (February), and the cold coil of product type D also fluctuates in the range of less than 200 tons to 2600 tons or more. Such in-process inventory fluctuations are not desirable from the viewpoint of having an appropriate in-process inventory quantity in preparation for demand fluctuations and express orders, and the production plan is incapable of operation due to insufficient inventory of the in-process inventory. There may be.

  On the other hand, in the example using this embodiment, according to the results of Tables 7 and 8, the production amount of each product type and the operation rate of each equipment not only satisfy the restriction ranges set in Tables 1 and 2. From the results in Table 9, it can be seen that the in-process inventory amount of each intermediate product also satisfies the restriction range set in Table 6. From the above, it can be seen that the in-process inventory amount of the intermediate product is an appropriate production plan within the appropriate range.

  In the above-described prior art example, the equation (5) has been specifically described. However, the present invention is not limited to this, and the in-process inventory amount of the intermediate process in a predetermined span or term for each product type or each process design is calculated. Without considering the restriction of being in the proper range, the amount processed in the subsequent process does not exceed the amount processed in the previous process, and the total load for each term of each facility determined by the processing capacity does not exceed the facility capacity For each term of each product type, the marginal profit is maximized while satisfying only the constraint that the total production volume of the span that constitutes the term is within the range of the production volume lower limit value and within the production volume upper limit value. Any formula that finds a solution for the production volume of each span can be compared.

  Thus, according to the production plan creation method, the production plan creation device, and the program according to the present embodiment, the amount to be processed in the subsequent process does not exceed the amount to be processed in the previous process, and each of the values obtained by the processing capacity is obtained. The constraint that the total load of each equipment term does not exceed the equipment capacity, and the total production volume of the spans that make up the relevant term is within the range between the production lower limit and the production upper limit for each term of each product type. In addition to the restriction that there is, the preset in the period (all terms) when the production plan is created while satisfying the restriction that the in-process inventory amount of the intermediate process in the predetermined span or term for each product type or process design is within the appropriate range The determined evaluation index is determined to be the maximum. Therefore, when manufacturing multiple types of products in a multi-process production process, it is possible to optimize the production amount of each product while providing an in-process inventory within the appropriate range in the intermediate process. A production plan can be created.

  In addition, the in-process inventory of intermediate processes in a given span or term for each product type or process design, against the constraint that the amount of in-process inventory in a given span or term for each product type or process design is within the appropriate range A variable corresponding to the amount of deviation from the appropriate amount range is added, and the variable is added as a penalty to the evaluation index. Therefore, even if there is no solution that satisfies the constraint that the in-process inventory amount in the intermediate process is within the appropriate range, the solution can be obtained reliably, avoiding the result of no solution, and deviating from the appropriate range of the in-process inventory amount. A solution that minimizes the quantity is given priority.

  Furthermore, since the production amount for each process design and the load of each facility necessary for the production by the process design can be handled in a linear format, linear programming is applied to the calculation of the evaluation index. Therefore, even when the number of varieties and facilities is large, the production amount for each process design can be optimized at high speed.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims.

In the above-described embodiment, the upper and lower limits of the in-process inventory amount are set in the appropriate in-process inventory amount storage unit 7 with respect to the unit of the intermediate product in which a plurality of process ranges are collected. If there is no problem even if the labor is increased, the upper and lower limit values of the in-process inventory amount of each process (that is, a unit of one process and one intermediate product) may be set.
In addition, the upper and lower limits of the in-process inventory of intermediate products do not change with time, but the in-process inventory depends on the time (for example, for each term), taking into account seasonal changes in demand. The upper and lower limits of the quantity may be changed and set.
Although the upper and lower limit values of the in-process inventory amount are set for each product type, the upper and lower limit values of the in-process inventory amount may be set for each process design. This may correspond to a case where it is desired to secure an in-process inventory amount of the process design corresponding to the required quality because there is a possibility that a slight difference in quality may occur if the process design is different even for the same product type.

In the above-described embodiment, the optimum product configuration calculation unit 30 uses the formula shown in Equation 2 as the calculation formula for the in-process inventory quantity of the intermediate product. The definition of It is also equivalent to performing a modification such as directly _{adding the} expressions shown in Equations 2 and 3 to s _jnt in the constraint equation relating to the upper limit of the in-process inventory amount and the constraint equation relating to the lower limit of the in-process inventory amount.

Further, in the above-described embodiment, the evaluation index is the profit maximization and the production volume maximization, but is not limited thereto.
For example, for the purpose of maximizing the production amount, the total production that is the sum of the production amounts of all the varieties may be used as the evaluation index.
Also, it may be a weighted sum of profit and production. This case can be applied to the following cases.
・ To increase profits as much as possible while securing production volume.
・ If profits are the same, a product structure with a large production volume is desirable.
Furthermore, the total sales may be maximized by using the evaluation index as the sum of the selling prices for each product type. In this case, it can be applied when it is desired to determine a variety configuration that places more importance on the total deposit than profit.

  Further, in the above-described embodiment, a case has been described in which a production route that can be used for each product type is set in advance as a process design. However, the present invention can be applied even when an alternative facility exists in a predetermined product type. can do. In this case, the production plan creation apparatus 1 that executes the production plan creation method creates a production route in the alternative facility as a new process design based on the alternative facility rule registered in advance, and stores it in the production route information storage unit 11. Remember.

It is a block diagram of a production plan creation device concerning this embodiment. It is the flowchart explaining the procedure of the process of the production plan preparation method which concerns on this embodiment. It is a figure which shows an example of the production line made into the object of this embodiment. It is a figure which defines the intermediate product in each process design of the kind A.

Explanation of symbols

1 Production Plan Creation Device 2 Production Volume Information Storage Unit (Production Volume Information Storage Unit)
3. Raw material / sale price information storage (product information storage means)
4 Equipment information storage unit (equipment information storage means)
5 Evaluation index setting section 6 Term / span information setting section (term / span information setting means)
7 Appropriate in-process inventory quantity storage (appropriate in-process inventory quantity storage means)
10 Process load unit calculation unit (Process load unit calculation means)
11 Manufacturing route information storage unit (Manufacturing route information storage means)
20 Generated cost intensity unit (Acquired cost intensity unit)
21 Generated cost information storage unit (generated cost information storage means)
30 Optimal variety composition calculation part (optimum variety composition calculation means)
S1 Production amount information storage step, product information storage step, equipment information storage step, term / span information setting step, generated cost information storage step, appropriate in-process inventory amount storage step S2 process load intensity unit calculation step S3 generated cost intensity unit calculation step S4 Optimal product composition calculation step

Claims (27)

In a computer comprising a CPU and a storage device, a production plan creation device for optimizing the production amount of a plurality of product types produced in a plurality of processes,
The storage device
A term / span information setting means for storing a span that is a unit of minimum time for evaluating constraints, a term that is composed of one or more spans and is a unit for producing a production plan, and a number of terms for producing a production plan;
For each product type, one or more manufacturing routes to which equipment capable of processing a plurality of processes for manufacturing a product are assigned are registered as a process design, and the processing capability of each process is registered for each process design. Route information storage means;
Facility information storage means for registering facility capacity for each term of each facility;
Production quantity information storage means for registering the usable process design number, production quantity lower limit value, and production quantity upper limit value as a range of production quantity required for each term of each product type;
For each product type or each process design, the appropriate range of the in-process inventory amount of the intermediate process in the predetermined span or the term is all the same in the predetermined span or the term, or the predetermined span or Appropriate in-process inventory quantity storage means for changing and registering according to the term ;
With
The CPU
Based on the processing capability of each process stored in the manufacturing route storage means, the process load for each process for each process design, which means the processing time in each process for each process design required to produce a unit quantity of product Process load intensity calculation means for calculating intensity,
The process load basic unit calculated by the process load basic unit calculating means, the range of the production quantity stored by the production quantity information storage means, the equipment capacity stored by the equipment information storage means, and the proper in-process inventory With reference to the appropriate range of the in-process inventory amount of the intermediate process stored in the quantity storage means, for each process for each process design, the subsequent process is between the previous process and the subsequent process with respect to the previous process. Restrictions on the manufacturing amount of the preceding and following processes that the amount processed in the subsequent process does not exceed the amount processed in the previous process at the time until the required inter-process time, and the terms of each facility determined by the processing capacity The total capacity of each span does not exceed the facility capacity, and for each term of each of the varieties, the total production amount of spans constituting the term is greater than or equal to the production amount lower limit value and the production amount upper limit value. Within value And limitations on the scope of production to be within the scope, the variety or the process for each design at a given the span or the term of each of the cultivars was calculated based on the results or the process for each design from past operations Each process design in which the preset evaluation index is maximized while satisfying the restrictions on the appropriate range of the in-process inventory quantity, in which the in-process inventory quantity of each intermediate process in the predetermined span or term is the appropriate range Optimal variety composition calculation means for calculating the production volume of each span of
A production plan creation device comprising: The optimum product configuration calculating means is:
With respect to the constraint that the in-process inventory amount of the intermediate process in the term or the process design is within the appropriate range, the span or the process In addition to adding a variable corresponding to the amount of deviation from the appropriate range of the in-process inventory amount of the intermediate process in the term, adding the variable as a penalty to the evaluation index, a preset evaluation index that satisfies the constraints The production plan creation device according to claim 1, wherein the production amount of each span of each process design that is maximized is calculated.   3. The production plan creation apparatus according to claim 1, wherein the evaluation index is calculated by a linear programming method. In a computer comprising a CPU and a storage device, a production plan creation method executed by a production plan creation device for optimizing the production amount of a plurality of types of products produced in a plurality of processes,
By means of term / span information setting means constituting the production plan creation device, a span that is a unit of minimum time for evaluating constraints, a term that is composed of one or more spans and is a unit of production plan creation, and production plan creation A term / span information setting step for storing the number of terms to be performed;
With the manufacturing route information storage means constituting the production plan creation device, for each product type, one or more manufacturing routes to which equipment that can be processed for a plurality of processes for manufacturing a product is assigned and registered as a process design. For each process design, a manufacturing route information storage step for registering the processing capacity of each process;
Facility information storage step for registering facility capacity for each term of each facility by facility information storage means constituting the production plan creation device;
By the production amount information storage means constituting the production plan creation device, the process design number, the production amount lower limit value, and the production amount upper limit value that can be used as the range of the required production amount for each term of each product type Production quantity information storage step for registering,
By proper progress inventory amount storage means constituting the production plan creation device, for each design the breed or each said step, the proper range of the progress inventory of intermediate steps in a given the span or the term, the predetermined said span Or the appropriate in-process inventory amount storing step for registering all the same in the term, or changing and registering according to the predetermined span or the term ;
Each process design required to make a unit quantity of a product based on the processing capability of each process stored in the manufacturing route storage step by the process load basic unit calculation means constituting the production plan creation device. A process load intensity calculation step for calculating a process load intensity for each process for each process design meaning a processing time in the process;
By the optimum product configuration calculation means constituting the production plan creation device, the process load basic unit calculated in the process load basic unit calculation step, the range of the production amount stored in the production amount information storage step, and the equipment With reference to the facility capacity stored in the information storage step and the appropriate range of the in-process inventory amount of the intermediate process stored in the appropriate in-process inventory amount storage step, for each process for each process design, the post-process is In relation to the previous process, the amount of processing before and after the previous process and the amount of processing in the subsequent process at the time before the previous process and the time required before the subsequent process does not exceed the amount processed in the previous process. For each term of each type, the constraint, the constraint on the facility capacity that the total load for each term of each facility determined by the processing capacity does not exceed the facility capacity, Constraints to the scope of production the total production of the span of configuration is within the scope of within the production limit value or the production amount upper limit value, which is calculated based on the results from past operations the While satisfying the restrictions on the appropriate range of the in-process inventory amount that the in-process inventory amount of each intermediate process in the predetermined span or term for each product type or each process design is the appropriate range, a preset evaluation index is An optimum product configuration calculation step for calculating the production amount of each span of each process design that is maximized;
A production plan creation method characterized by comprising: The optimum product configuration calculation step includes:
With respect to the constraint that the in-process inventory amount of the intermediate process in the term or the process design is within the appropriate range, the span or the process In addition to adding a variable corresponding to the amount of deviation from the appropriate range of the in-process inventory amount of the intermediate process in the term, adding the variable as a penalty to the evaluation index, a preset evaluation index that satisfies the constraints The production plan creation method according to claim 4, wherein the production amount of each span of each process design that is maximized is calculated.   6. The production plan creation method according to claim 4, wherein the calculation of the evaluation index is performed by a linear programming method. In a computer having a storage device and a CPU, a program executed by a production plan creation device for optimizing the production amount of a plurality of types of products produced in a plurality of processes,
By means of term / span information setting means constituting the production plan creation device, a span that is a unit of minimum time for evaluating constraints, a term that is composed of one or more spans and is a unit of production plan creation, and production plan creation A term / span information setting step for storing the number of terms to be performed;
With the manufacturing route information storage means constituting the production plan creation device, for each product type, one or more manufacturing routes to which equipment that can be processed for a plurality of processes for manufacturing a product is assigned and registered as a process design. For each process design, a manufacturing route information storage step for registering the processing capacity of each process;
Facility information storage step for registering facility capacity for each term of each facility by facility information storage means constituting the production plan creation device;
By the production amount information storage means constituting the production plan creation device, the process design number, the production amount lower limit value, and the production amount upper limit value that can be used as the range of the required production amount for each term of each product type Production quantity information storage step for registering,
By proper progress inventory amount storage means constituting the production plan creation device, for each design the breed or each said step, the proper range of the progress inventory of intermediate steps in a given the span or the term, the predetermined said span Or the appropriate in-process inventory amount storing step for registering all the same in the term, or changing and registering according to the predetermined span or the term ;
Each process design required to make a unit quantity of a product based on the processing capability of each process stored in the manufacturing route storage step by the process load basic unit calculation means constituting the production plan creation device. A process load intensity calculation step for calculating a process load intensity for each process for each process design meaning a processing time in the process;
By the optimum product configuration calculation means constituting the production plan creation device, the process load basic unit calculated in the process load basic unit calculation step, the range of the production amount stored in the production amount information storage step, and the equipment With reference to the facility capacity stored in the information storage step and the appropriate range of the in-process inventory amount of the intermediate process stored in the appropriate in-process inventory amount storage step, for each process for each process design, the post-process is In relation to the previous process, the amount of processing before and after the previous process and the amount of processing in the subsequent process at the time before the previous process and the time required before the subsequent process does not exceed the amount processed in the previous process. For each term of each type, the constraint, the constraint on the facility capacity that the total load for each term of each facility determined by the processing capacity does not exceed the facility capacity, Constraints to the scope of production the total production of the span of configuration is within the scope of within the production limit value or the production amount upper limit value, which is calculated based on the results from past operations the While satisfying the restrictions on the appropriate range of the in-process inventory amount that the in-process inventory amount of each intermediate process in the predetermined span or term for each product type or each process design is the appropriate range, a preset evaluation index is An optimum product configuration calculation step for calculating the production amount of each span of each process design that is maximized;
A program installed on the storage device and read and executed by the CPU. The optimum product configuration calculation step includes:
With respect to the constraint that the in-process inventory amount of the intermediate process in the term or the process design is within the appropriate range, the span or the process In addition to adding a variable corresponding to the amount of deviation from the appropriate range of the in-process inventory amount of the intermediate process in the term, adding the variable as a penalty to the evaluation index, a preset evaluation index that satisfies the constraints The program according to claim 7, wherein a production amount of each span of each process design that is maximized is calculated.   9. The program according to claim 7, wherein the evaluation index is calculated by a linear programming method. The optimum product mix calculation means, based on the following formula shown in Equation 1, the production planning system according to claim 1 or 2 Widgets inventory of the intermediate step and calculating by linear programming.

The proper progress inventory amount storage means, together a plurality of said intermediate step to define an intermediate product state in the process that the large enclosed, registers the proper range widget inventory of each of the span in the intermediate product unit,
The production plan creation device according to claim 1 or 2 , wherein the optimum product configuration calculation means calculates an in-process inventory amount in the intermediate product unit . The optimum product mix calculation unit has the formula shown in Equation 2 using the constant Likn for classifying the intermediate product defined, or, based on the following formula shown in Formula 3, progress inventory of the intermediate product unit The production plan creation device according to claim 11 , wherein the quantity is calculated by a linear programming method .

  The production plan creation device according to any one of claims 1 to 3 and 10 to 12, wherein the optimum product configuration calculation unit sets the evaluation index based on a production volume maximization. The storage device
Product information storage means for storing raw material costs and selling prices for each product type;
Generated cost information storage means for storing a variable cost that is a cost generated to process a unit amount in each step;
Further comprising
The CPU
The generated cost for calculating the generated cost base unit for each process design, which means the cost for each process design generated to produce a unit quantity based on the variable cost stored in the generated cost information storage means Basic unit calculation means;
Further comprising
The optimum product configuration calculating means refers to the generated cost basic unit calculated by the generated cost basic unit calculating means, the raw material cost and the selling price stored in the product information storage means, and maximizes profit or The production plan creation device according to any one of claims 1 to 3 and 10 to 12, wherein the evaluation index is set based on a weighted sum of profits or production amounts. The storage device
Product information storage means for storing a selling price for each of the types;
Further comprising
The optimal product type composition calculating means maximizes total sales by referring to the generated cost basic unit calculated by the generated cost basic unit calculating means and the raw material cost and the selling price stored in the product information storage means. The production index creation device according to claim 1, wherein the evaluation index is set based on the above. The optimum product mix calculating step, based on the following equation shown in Equation 1, the production planning method according to claim 4 or 5 Widgets inventory of the intermediate step and calculating by linear programming.

The proper progress inventory amount storing step, together a plurality of said intermediate step to define an intermediate product state in the process that the large enclosed, registers the proper range widget inventory of each of the span in the intermediate product unit,
6. The production plan creation method according to claim 4, wherein the optimum product configuration calculation step calculates an in-process inventory quantity in the intermediate product unit . The optimum product mix calculation step has the formula shown in Equation 2 using the constant Likn for classifying the intermediate product defined, or, based on the following formula shown in Formula 3, progress inventory of the intermediate product unit The production plan creation method according to claim 17 , wherein the quantity is calculated by a linear programming method.

  19. The production plan creation method according to any one of claims 4 to 6, and 16 to 18, wherein the optimum product configuration calculation step sets the evaluation index based on a production volume maximization. Product information storage means for storing raw material costs and selling prices for each of the types by product information storage means constituting the production plan creation device;
A generated cost information storage step for storing a variable cost, which is a cost generated to process a unit amount in each process by the generated cost information storage means constituting the production plan creation device;
Based on the variable cost stored in the generated cost information storage step, the cost for each process design generated to make a unit quantity of the product is generated by the generated cost basic unit calculating means constituting the production plan creating device. An incurred cost unit calculation step for calculating an incurred cost unit for each process design,
Further comprising
The optimum product configuration calculating step refers to the generated cost basic unit calculated in the generated cost basic unit calculating step, the raw material cost and the selling price stored in the product information storing step, and maximizes profit or The production plan creation method according to any one of claims 4 to 6, and 16 to 18, wherein the evaluation index is set based on a weighted sum of profits or production amounts. Product information storage step for storing a selling price for each product type by means of product information storage means constituting the production plan creation device;
Further comprising
The optimum product configuration calculating step refers to the generated cost basic unit calculated in the generated cost basic unit calculating step, and the raw material cost and the selling price stored in the product information storing step to maximize the total sales. The production plan creation method according to claim 4, wherein the evaluation index is set based on the method. The optimum product mix calculating step, based on the following equation shown in Equation 1, the program according to claim 7 or 8 Widgets inventory of the intermediate step and calculating by linear programming.

The proper progress inventory amount storing step, together a plurality of said intermediate step to define an intermediate product state in the process that the large enclosed, registers the proper range widget inventory of each of the span in the intermediate product unit,
The program according to claim 7 or 8 , wherein the optimum product configuration calculation step calculates an in-process inventory quantity in the intermediate product unit . The optimum product mix calculation step has the formula shown in Equation 2 using the constant Likn for classifying the intermediate product defined, or, based on the following formula shown in Formula 3, progress inventory of the intermediate product unit The program according to claim 23 , wherein the quantity is calculated by linear programming.

  The program according to any one of claims 7 to 9, and 22 to 24, wherein the optimum product configuration calculation step sets the evaluation index on the basis of maximization of production. Product information storage means for storing raw material costs and selling prices for each of the types by product information storage means constituting the production plan creation device;
A generated cost information storage step for storing a variable cost, which is a cost generated to process a unit amount in each process by the generated cost information storage means constituting the production plan creation device;
Based on the variable cost stored in the generated cost information storage step, the cost for each process design generated to make a unit quantity of the product is generated by the generated cost basic unit calculating means constituting the production plan creating device. An incurred cost unit calculation step for calculating an incurred cost unit for each process design,
Further comprising
The optimum product configuration calculating step refers to the generated cost basic unit calculated in the generated cost basic unit calculating step, the raw material cost and the selling price stored in the product information storing step, and maximizes profit or The program according to any one of claims 7 to 9, 22 to 24, wherein the evaluation index is set based on a sum of weights of profits or production amounts. Product information storage step for storing a selling price for each product type by means of product information storage means constituting the production plan creation device;
Further comprising
The optimum product configuration calculating step refers to the generated cost basic unit calculated in the generated cost basic unit calculating step, and the raw material cost and the selling price stored in the product information storing step to maximize the total sales. The program according to claim 7, wherein the evaluation index is set based on the program.

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