JP2006331262A - Material requirement planning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a MPR (Material Requirements Planning) apparatus capable of reducing operator's load by quickly and accurately determining a timing of ordering intermediate assemblies set as independent required articles even when the date of delivery of a final product is changed or the design of parts is changed. <P>SOLUTION: When there are a plurality of independent required articles including a product and its constitutional parts, these articles are previously registered in a database in association with each other by a common key, and when material requirement planning of a product planned by a requirement planning processing means 6 is changed by changing the date of delivery of the product or specifying a design changing period, the common key of the articles related to each other is referred to synchronously with the change, the material requirement planning of other independent required articles is linked and the material requirement planning of the other linked articles is changed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a material requirement planning device for planning material requirements planning (MRP: Material Requirements Planning).

  In general, when planning a material requirement plan, if there is a parent-child relationship (BOM: hierarchical structure relationship) between a product and its component parts, for example, as shown in FIG. When it is configured with a combination of TB and individual parts a to e, the required quantity of product, lead time of the product and each component, inventory quantity, configuration information describing the parent-child relationship as described above, etc. To calculate how many of each component item will be required until the final product is obtained, that is, calculate the required date and required amount for each item, and plan the material requirement. Information on ordering arrangements and work instructions is generated for each component based on the plan. Note that the material requirement plan in this case is normally developed from the upper items to the lower items, and the MRP process ends when plans for all the items are made.

  In the following, the required date and required amount for an item are set and input by the operator himself as an independent demand item, and the required date and required amount are determined according to the material requirement plan designed for this independent demand item. Coming items are called dependent demand items.

  By the way, even when such a material requirement plan for a certain product X is drawn up, it may be necessary to switch each item constituting the product for quality improvement or design change. For example, it may be necessary to change the part e in FIG. 2 to e ′.

  In order to deal with the case of switching some of these component items, the conventional technology does not require the old items before switching to remain in stock or produce new items of the old items before switching. If there is a stock of the old item, after assigning all the items before switching based on the material requirement plan that has been planned earlier, it is possible to dispose of the stock, and then the new material requirements for the item after switching A quantity plan is created (see, for example, Patent Document 1).

  In addition, when placing an order for each item based on the material requirement plan formulated for one product X, the production volume, throughput, safety stock quantity, etc. change due to improvements in production efficiency, etc. The arrangement of each item may change.

  In order to cope with this, in the prior art, information (item specific information) of the item whose arrangement method is changed is managed for each generation, and when the item arrangement method is changed, the item arrangement is performed based on this item specific information. There has also been proposed a technique that enables a new material requirement plan reflecting a change in method (see, for example, Patent Document 2).

JP-A-7-254023 JP 11-25181 A

  By the way, as shown in FIG. 2, when manufacturing a certain product X, manufacture of intermediate assemblies TA, TB, etc. in an intermediate process may be outsourced to a subcontractor. In such a case, in order to deal with an unexpected situation such as a trouble, the number of days from the scheduled date for actually assembling the product X with the allowance in terms of time can be taken into account. In many cases, materials are arranged ahead of schedule, based on the advance schedule.

  Now, as shown in FIG. 5, when focusing only on the product X and its components TA, TB, and e, in the material requirement plan (1) previously planned for the product X, the required date for the intermediate assembly is March. Even when scheduled on the 25th, the material requirement plan (2) with the intermediate assembly TA set as an independent demand item and the intermediate assembly TA moved forward, for example, March 21 May stand independently. In addition, the period in which purchase and acquisition for each item is necessary is often several days in practice, but here, for the sake of explanation, the necessary period for each item is regarded as one day for convenience. .

  In the conventional material requirement planning device (hereinafter abbreviated as MRP planning device), once a certain item is set as an independent demand item, for example, TA, the material requirement planning (independent demand item TA) ( 2) is a separate plan from the material requirement plan (1) of other independent demand items, for example, product X. For this reason, the relationship between the schedules of both plans X and TA (1) and (2) is lost.

  Therefore, even if there is a change in the plan (1) of the product X that is one independent demand item, the material requirement plan (2) for the intermediate assembly TA that is the other independent demand item is changed synchronously. It will never be done. As a result, when the material requirement plan (1) for product A is set with the product X as an independent demand item and the intermediate assembly TA as a dependent demand item, the material requirement for this item with the intermediate assembly TA as an independent demand item When the plan (2) is made, it may happen that the schedule is not well-balanced.

  For example, when the delivery date of the product X is earlier than the schedule originally scheduled at the request of the user (in this example, the delivery date was originally scheduled for March 30 but changed to March 27), When the product X and the intermediate assembly TA are both independent demand items, the material requirement plan (2) of the intermediate assembly TA is a plan different from that of the product X. Therefore, the material requirement of the product X Even if the plan is changed from (1) to (3), this is not reflected in the material requirement plan (2) of the intermediate assembly TX, and purchase orders for the intermediate assemblies TA, TB and purchased parts b to e are made. It is not possible to determine an appropriate time for. That is, in the material requirement plan (3) after the delivery date change of the product X, the necessary date of the intermediate assembly TA is March 22, and the period necessary for the advancement of the intermediate assembly TA is not taken into consideration.

  In addition, for example, in order to improve quality, etc., when a component X of a product X, for example, a part e is redesigned to be partly up-to-date to e ′ and the product X is started to be sold as a new product, It is necessary to determine when to change the purchased part from e to e ′ from the sales start date of the product X. Even in this case, when the product X and the intermediate assembly TA are both independent demand items, the material requirement plan (2) of the intermediate assembly TA is the same as the material requirement plan (3) of the new product X by parts switching. Is a separate plan, it is not possible to appropriately determine when to change the purchased part from e to e ′ over the schedule based on the material requirement plan (3) of product X.

  That is, when the sales start date of the product X when the part e is switched to e ′ is determined on March 27, and the material requirement plan (3) of the product X is formulated accordingly, the part is changed from e The date of switching to e ′ will be March 14, but this plan (3) is a plan separate from the material requirement plan (2) of the intermediate assembly TA, so the intermediate assembly TA is brought forward. The necessary period is not considered. For this reason, the time (March 14) at which the part is switched from e to e 'is set later than the switching date that should be set at an earlier stage with a margin.

  The conventional techniques described in Patent Documents 1 and 2 described above are based on the material requirement plan for product X, which is the highest independent demand item. In the case where the intermediate assembly TA is an independent demand item, it is actually difficult to determine an appropriate time to change the purchased part from e to e ′.

  Therefore, conventionally, in order to determine the timing for ordering the intermediate assembly TA when there is such a change in the delivery date of the product X or a change in the design of the parts, it has been proposed again in accordance with the change in the delivery date or the design change. Necessary to advance the intermediate assembly TA by comparing the material requirement plan (3) for the product X with the material requirement plan (2) already planned for the intermediate assembly TA as an independent demand item. In consideration of a long period, the material requirement plan (4) is re-developed for the intermediate assembly TA, and the order arrangement timing for each part TB, d, e, etc. is determined. In this example, in the material requirement plan (2) of the product X, the required date for the intermediate assembly TA is March 22, but the starting date is set to March in consideration of the period required for the intermediate assembly TA to be advanced. The material requirement plan (4) on the 18th is formulated again.

  Thus, conventionally, when there is a change in the delivery date of the product X or a change in the design of the parts, the operator has to plan each order in order to appropriately determine the order for ordering the intermediate assembly set as an independent demand item. There was a problem that it was necessary to adjust the schedule for each of (1) to (4), which not only required extra effort and labor for planning, but also lacked real-time performance, and also made mistakes during planning. .

  The present invention has been made to solve the above-described problems. Even when there is a change in the delivery date of the final product or a change in the design of the parts, the timing of ordering arrangement of intermediate assemblies set as independent demand items, etc. It is an object of the present invention to provide an MRP planning apparatus that can accurately determine the time limit within a short time to reduce the load on the operator and eliminate the occurrence of mistakes during planning.

  In order to achieve the above object, the present invention provides information such as the delivery time and required amount of a product, the lead time and inventory amount of each item of the product and a plurality of parts and intermediate assemblies constituting this product, and each item. In a material requirements planning device comprising: a database in which configuration information describing the parent-child relationship of the product is registered; and a requirements planning processing means for planning a material requirements plan for independent demand items using this database. The configuration is adopted.

  That is, according to the present invention, when there are a plurality of independent demand items including a product and its component parts, an association means for associating these items with each other by a common key is provided, and the requirement plan processing means includes a delivery date of the product. If the material requirements plan of the product is changed due to the change or the design change timing of the parts, refer to the common key of the items associated with each other by the association means in synchronization with this, It is characterized in that the material requirement plan of other items is changed by linking the material requirement plan of the independent demand item.

  According to the present invention, even when the product and the parts constituting it are set as independent demand items, if it is necessary to associate these items with each other's schedule, In response to this, a common key is set for items to be associated by the plan association means. If the material requirement plan previously planned for the product is changed due to a change in the delivery date of the product, which is an independent demand item, or a change in the design of the part, the requirement plan processing means synchronizes with this. Referring to the key common to each item related by linking the material requirement plan planned for other independent demand items, the material requirement plan for other items is changed. For this reason, it is possible to accurately determine the timing of ordering arrangement for other intermediate assemblies set as independent demand items within a short time. As a result, it is possible to reduce the load on the operator as compared with the conventional case, and it is possible to eliminate the occurrence of mistakes at the time of planning.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a hardware configuration of an MRP planning apparatus according to Embodiment 1 of the present invention.

  The MRP planning apparatus 1 according to the first embodiment includes an item database 2, an item configuration database 3, a requirement plan database 4, a material requirement plan association database 5, a requirement plan processing unit 6, an input / output device 7, an order plan file. 8 and a work plan file 9.

  In the item database 2, each product and each item of a plurality of parts and intermediate assemblies constituting these products are registered. In the item configuration database 3, information on a parent-child relationship (BOM: hierarchical configuration relationship) between a product and its component parts is registered as item configuration information. In the requirement planning database 4, information such as the delivery time and required quantity of the product, the lead time and the inventory quantity for each item of the product and each component are registered. In addition, in the material requirement plan association database 5, in order to link the material requirement plans for each independent demand item to each other, a key for associating each item of the product with the components constituting the product and each item. Is registered.

  The requirement plan processing unit 6 makes a material requirement plan for an independent demand item based on the information registered in each of the databases 2 to 5 according to a control program installed in advance. Consists of a computer or the like. Then, when the material requirement plan of the product is changed due to the change of the delivery date of the product or the design change timing specification of the part, the requirement plan processing unit 6 synchronizes with this and the material requirement plan association database 5 The material requirement plan for other items constituting the product is changed by linking the material requirement plan of each item associated with each other with reference to the information of the item.

The input / output device 7 inputs various information to be registered in each of the databases 2 to 5 and a command for the requirement plan processing unit 6 and outputs a result processed by the requirement plan processing unit 6. For example, a keyboard, a mouse, a printer, a display, and the like (not shown) are provided.
The input / output device 7, the requirement plan processing unit 6, and the material requirement plan association database 5 constitute association means in the scope of claims.

  The order plan file 8 is for registering order plan information for each item generated based on the material requirement plan prepared by the requirement plan processing unit 6. The work plan file 9 is for registering work plan information for each item generated based on the material requirement plan prepared by the requirement plan processing unit 6. The order plan for each item registered in the order plan file 8 is an order form, and the work plan for each item registered in the work plan file 9 is a work instruction sheet, as necessary. It is output to the input / output device 7.

  Next, the planning operation of the material requirement plan in the MRP planning apparatus 1 having the above configuration will be described with reference to the explanatory diagram shown in FIG. 3 and the flowchart shown in FIG. Here, as an example, it is assumed that the product X is configured by combining intermediate assemblies TA and TB and individual parts a to e, and has a parent-child relationship (BOM: hierarchical configuration relationship) as shown in FIG. Only the product X and its components TA, TB, and e will be described. In this case, the period in which purchase and acquisition for each item is necessary is often several days in reality, but here, for convenience, the necessary period for each item is regarded as one day.

[A] Planning of Material Requirement Plan for Each Independent Demand Item In order to plan a material requirement plan for product X, which is an independent demand item, when a planning command for product X is input from the input / output device 7, this Accordingly, the requirement plan processing unit 6 makes a material requirement plan for the product X based on the information registered in each of the databases 2 to 4 in accordance with the control program installed in advance. In this case, it is assumed that the material requirement plan prepared for the product X is, for example, the plan (1) in FIG. In this plan (1), the required date for the intermediate assembly is scheduled for March 25.

  On the other hand, if it is necessary to arrange materials for an intermediate assembly, for example TA, ahead of the date planned by the above-mentioned material requirement plan (1) planned for product X, this advanced date (here Then, the original material requirement plan for the intermediate assembly TA will be drafted starting on March 21).

  For this purpose, after setting that the intermediate assembly TA is an independent demand item from the input / output device 7 to the requirement planning processing unit 6, a command for planning the intermediate assembly TA is input. In response to this, the requirement plan processing unit 6 makes a material requirement plan for the intermediate assembly TA based on the information registered in the databases 2 to 4. In this case, it is assumed that the material requirement plan designed for the intermediate assembly TA is, for example, the plan (2) in FIG. In this plan (2), the required date for the intermediate assembly is scheduled for March 21.

[B] Association of plans planned for each independent demand item When the material requirement plans (1) and (2) are formulated with the product X and the intermediate assembly TA as independent demand items, both plans (1), The relevance of the schedule (2) is essentially lost.

  However, even if the product X and the component TA constituting the product X are set as independent demand items, if the mutual association is required for both A and TA, the input / output device 7 selects the item to be associated. specify. In response to this, the requirement plan processing unit 6 sets a common key for the items to be associated, information on the items that need to be associated with each other and information on the common key for associating these items with the requirement plan association database 5. Register with. In this example, each item of the product X and the intermediate assembly TA, and a common key “α” for associating them with each other are encoded and registered in the requirement plan association database 5.

[C] Change in material requirement plan due to change in delivery date of product X When the delivery date of product X is earlier than the originally scheduled date according to the user's request, for example, the delivery date is initially scheduled for March 30 However, if it is changed on March 27, it will be necessary to formulate a material requirement plan for product X starting from March 27 again. Therefore, the input / output device 7 designates the required date of the product X on March 27, and instructs that a new material requirement plan for the product X with this date as the starting date be drawn up.

  The requirement plan processing unit 6 searches the requirement plan association database 5 in synchronism with the planning of a new material requirement plan for the product X, and the items X and TA that need to be associated in advance are registered. Check whether there is a common key “α” for. If there is a common key “α” for both items X and TA, the material requirement plan (2) already planned for the other independent demand items TA is linked.

  Subsequently, the requirement planning processing unit 6 uses the starting date of the plan (2) already planned for the intermediate assembly TA (March 21 in this example) as a reference, and from this reference date, Calculate the time period required to advance according to the required amount, lead time, inventory amount, etc. In other words, in this example, the period required for the advancement of the intermediate assembly TA is calculated as 4 days. Then, the requirement plan processing unit 6 drafts a material requirement plan (3) for the intermediate assembly TA starting from March 17 which is four days ahead of March 21. Therefore, in accordance with the change in the material requirement plan for the product X, the plan (3) of the intermediate assembly TA has a necessary date of March 17 and a necessary date of the subordinate parts d and e is March 13 respectively. Will be changed on March 9th. Thereby, the required date of each item TA, d, e can be determined automatically and appropriately.

  As described above, when the material requirement plan of the product X is changed, the material requirement plan of the intermediate assembly TX is automatically changed from (2) to (3) in synchronization with this, and at that time, the intermediate requirement TX Since the advance period required for purchasing the assembly TX is reflected in the newly planned plan (3), the timing for purchasing or placing the order for the intermediate assembly TA and its subordinate parts d and e Can always be determined appropriately.

[D] Determining when to change the design of parts To improve the quality, etc., change the component parts of product X, for example, part e to the latest, change it to e ', and start selling product X as a new product In this case, it is necessary to determine the timing for changing the purchased part from e to e ′ according to this from the sales start timing of the product X. For example, when the sales start date of the new product X associated with the switching of the part e is March 27, it is necessary to determine when to change the purchased part from e to e ′.

  For this purpose, as shown in the flowchart of FIG. 4, in order to determine the sales start time of the new product X by switching the parts, the sales start time of the product X is designated as the starting date by the input / output device 7 (S1), Instruct to make a new material requirement plan for product X.

  When preparing a new material requirement plan for the product X, the requirement plan processing unit 6 searches the requirement plan association database 5 in synchronism with this, and the items X and TA that require pre-registered association are searched. It is checked whether there is a common key “α” relating to (S2). At this time, if there is a common key “α” for both items X and TA, the material requirement plan (2) for the item TA planned for other independent demand items is linked.

  Subsequently, as in the case of changing the delivery date of the product X in [C] above, the requirement plan processing unit 6 starts the start date of the plan (2) already planned for the intermediate assembly TA (March in this example). 21 days) as a reference, a period (4 days in this example) necessary for advancement is calculated from the reference date according to the required amount, lead time, inventory amount, etc. of the intermediate assembly TA (S3).

  Then, the requirement plan processing unit 6 formulates a material requirement plan (3) for the intermediate assembly TA starting from March 17 which is four days ahead of March 21 as the reference date (S4). . Therefore, the switching date of the part d under the intermediate assembly TA is determined on March 13, and the switching date of the part from e to e 'is determined on March 9. Thereby, each switching date of each item TA, d, e can be determined automatically and appropriately.

  The requirement plan processing unit 6 registers the ordering plan information for each item TA, d, e in the ordering plan file 8 when each switching date of each item TA, d, e is determined in this way. For example, an order form in which the item e is switched to e ′ can be created by printing out the information in the plan file 8 or the like.

  On the other hand, in S2, if the common key is not found even after searching for the common key related to each item registered in the requirement plan association database 5 in advance, the requirement plan processing unit 6 inputs / outputs. A warning signal to the effect that there is no item association is output to the device 7 (S6), and the switching date for switching the item e to e ′ based on the material requirement plan (2) for the original intermediate assembly TA ( In this example, March 13) is designated (S7).

  As described above, in the MRP planning apparatus 1 according to the first embodiment, even when the product X and the intermediate assembly TA are set as independent demand items, the delivery date of the product X and the design change of parts are changed. When the previously planned plan (1) is changed, the material requirement plan (2) for the intermediate assembly TA, which is another independent demand item, is synchronized with the original plan (2). Since the schedule is changed to the new plan (3) reflecting the schedule, it is not necessary to adjust the schedule for each independent demand item through the operator. For this reason, it is possible to save extra labor and labor required for planning as compared with the prior art, to reduce the load on the operator, to improve the real-time performance, and to eliminate the occurrence of mistakes during planning.

  In the first embodiment, for ease of understanding, the intermediate assembly TA has been described as an independent demand item, focusing on the product X and its components TA, TB, e. The same applies to the operation when other intermediate assembly TB or the like is an independent demand item. In the first embodiment, the case where the product X and the component parts TA, TB, a to e have a parent-child relationship as shown in FIG. 2 is described as an example. However, the embodiment is limited to such a relationship. Of course, it is not a thing. Of course, the specific schedule of each plan is only an example.

It is a block diagram which shows the hardware constitutions of the material requirement plan planning apparatus in Embodiment 1 of this invention. It is a tree figure which shows an example of the parent-child relationship with a product and the intermediate assembly and components which comprise this. It is explanatory drawing of the planning operation | movement of the material requirement plan in the material requirement plan planning apparatus of Embodiment 1 of this invention. 5 is a flowchart for explaining a planning operation of a material requirement plan when there is a design change of a part in the material requirement planning system according to the first embodiment of the present invention. It is explanatory drawing of planning operation | movement of the material requirement plan in the conventional material requirement plan planning apparatus.

Explanation of symbols

1 Material requirements planning (MRP) planning device, 2 item database,
3 Item configuration database, 4 Requirements planning database,
5 requirement planning association database, 6 requirement planning processing unit (requirement planning processing means), 7 input / output device.

Claims (2)

A database that stores information such as the lead time and required quantity of products, the lead time and inventory quantity of each item of the product and multiple parts and intermediate assemblies that make up this product, and configuration information that describes the parent-child relationship of each item And a material requirements planning device comprising a requirements planning processing means for planning material requirements planning for independent demand items using this database,
When there are a plurality of independent demand items including products and their component parts, an association means for associating these items with each other by a common key is provided, and the requirement planning processing means changes the delivery date of the product or changes the design of the parts. If the material requirement plan of the product is changed due to the specification of the time, the material requirement of other independent demand items is referred to by referring to the common key of the items associated with each other by the association means in synchronization with this. The quantity plan is linked, and the material requirement plan for the other linked items is changed. When the requirement planning processing means changes the material requirement plan of the linked other item in synchronization with the change of the material requirement plan of the product, the material requirement already planned for the other item Based on the starting date of the plan, the schedule is changed by calculating the period necessary for the advance according to the required amount, lead time, inventory amount, etc. of the item from the starting date as the reference The material requirement planning apparatus according to claim 1.

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