JP2002244720A - Production plan leveling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily realize dispersion of a production plan according to production capacity also when shipment is concentrated on a specific day. SOLUTION: A unit group arranging means 5 arranges all the unit groups in order of a production completion upper limit day. A production capacity cumulative means 6 cumulates and adds production capacity from the first day to the last day in an object period of a production plan. A production unit number cumulative means 7 determines the total number of production units required for every day by considering that the production of all the units including in each unit group is completed till each production completion upper limit day and cumulates and adds the number. A cumulative working ratio calculation means 8 determines a cumulative working ratio showing the ratio of a production unit number cumulative value occupied in the production capacity cumulative value for every day from the first day of the period to the last day of the period. A production plan setting means 9 sets a production plan of each day so that the cumulative working ratio on a day showing a peak in the period may be substantially equal to the working ratio from the first day of the period to the day showing the peak.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a production plan smoothing method, a production plan smoothing system, a computer program, and the like, which are suitable for production management of order-made production with a designated delivery date.

[0002]

2. Description of the Related Art When a house maker receives an order for house construction, a factory produces building materials and units necessary for house construction work. The production plant produces parts for each unit, such as room units, balcony units, and entrance units, and performs preliminary assembly. These units are planned to be completed and shipped around the same time. At a factory that manufactures units for custom-built houses with different specifications for each house,
The production process of each unit is distributed and the allocation process is performed.
Unlike mass-produced products, order-made products make such unit-by-unit production management very complicated. Thus, while a skilled administrator performs the assignment process based on experience, a computer or the like is also used.

[0003]

However, the above-mentioned prior art has the following problems to be solved. In particular, in the case of a build-to-order production of a house, a production plan is often made after a shipment date is specified. In addition, it is difficult to freely move this shipping date, and in many cases, many orders are concentrated on the same shipping date due to a date such as the calendar date, such as Oyakichi Day. Furthermore, there is also a property that cancellation, change, addition, etc. are likely to occur frequently for the convenience of the customer. In such a situation, it is not easy to always carry out efficient production planning. Further, in order to reduce the cost by averaging the staffing, it is necessary to carry out a leveling process for dispersing the processes on a daily basis as much as possible according to the production capacity of the factory.

However, when the delivery date is changed, or an order is added or canceled relatively frequently, it is necessary to promptly change the production plan each time. If this is performed by a skilled administrator, a heavy burden is imposed on the administrator. Not only in house construction, but in order-made production where delivery dates are predetermined and shipping times tend to be concentrated, similar problems occur widely. The present invention provides a method capable of automatically and quickly executing a production plan leveling process in such a complicated production management field. Further, it is not easy to replace the operation of a skilled administrator with computer processing as it is. Even if the processing is performed manually, the efficiency is high, but the processing by the computer is rather inefficient. Of course, the reverse is also true. Therefore, there is a demand for the development of a method capable of performing a production plan leveling process most efficiently and accurately by a computer. The present invention provides a method capable of automatically and quickly executing a production plan leveling process in such a complicated production management field. The present invention further provides a production plan leveling system capable of automatically leveling irregularities in a production plan by computer processing even when extreme shipment concentration occurs, a computer program for executing the same, and the like. With the goal.

[0005]

The present invention employs the following structure to solve the above problems. <Structure 1> When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date must be produced during a period to be subjected to a production plan, production of all units included in each unit group must be completed. The production completion upper limit date must be determined, all the unit groups are arranged in the order of the production completion upper limit date, the daily production capacity is determined from the first day to the end of the period covered by the production plan, and the daily production capacity is determined. The total production capacity is calculated by adding the production capacity cumulatively from the first day of the above period to that day, and assuming that the production of all the units included in each unit group is completed by the above production completion upper limit date, In addition to calculating the number of production units, obtain the cumulative value of the number of production units by adding the required total number of production units from the first day of the above period to the relevant day for each day. From the end of the period to the end of the period, the cumulative operating rate indicating the ratio of the cumulative number of production units to the cumulative production capacity for each of the above-mentioned days is calculated, and the cumulative operating rate at which the cumulative operating rate peaks during the period is calculated as A production plan leveling method, wherein a production plan for each day is set so as to be substantially equal to an operation rate from the first day of the period to the day showing the peak.

<Structure 2> In the production plan leveling method described in Structure 1, the operation rate of the day on which the cumulative operation rate shows a peak, and the production capacity of each day from the first day of the period to the day on which the peak shows the peak. A production plan leveling method, wherein a product of the production plan and the production capacity is set to an upper limit of the production capacity of each day.

<Structure 3> In the production plan leveling method described in Structure 1, the day after the peak is set as a period to be a target of a new production plan, and the production plan of each day is set until the end of the period. A production plan leveling method, characterized by repeating a process for setting a production plan.

<Structure 4> In the production plan leveling method described in Structure 1, the process of manufacturing each part of a product with a predetermined delivery date is defined as one unit, and when the man-hour of the process is a standard value, the number of units is one. If the number is more than the standard value, the number of units is a natural number of 1 or more.
A production plan leveling method characterized by the following natural numbers.

<Structure 5> When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date have to be produced during a period to be subjected to a production plan, production of all units included in each unit group is performed. A unit group arranging means for arranging all the unit groups in the order of the production completion upper limit day which defines the production completion upper limit date to be completed, and a daily basis from the first day to the end of the period to be subjected to the production plan. Means for determining the production capacity of each unit, a production capacity accumulation means for obtaining a production capacity accumulation value obtained by cumulatively adding the production capacity from the first day of the period to the day, and all the units included in each unit group by the above-mentioned production completion upper limit day. The required total number of production units per day is determined assuming that the production of the unit is completed, and the required total number of production units per day from the first day of the above period to that day is calculated. A production unit number accumulating means for obtaining a product addition cumulative value, and a cumulative operating rate indicating a ratio of the production unit cumulative value to the production capacity cumulative value for each day from the first day of the period to the end of the period. A cumulative operating rate calculating means, such that the cumulative operating rate is the same as the operating rate from the first day of the period to the day at which the peak indicates the peak during the period in which the cumulative operating rate indicates a peak in the period. A production plan leveling system, comprising: a production plan setting means for setting a production plan.

<Structure 6> When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date must be produced during a period to be subjected to a production plan, production of all units included in each unit group is performed. The process of arranging all the unit groups in the order of the production completion upper limit date by determining the production completion upper limit date to be completed, and the daily production capacity from the first day to the end of the period covered by the production plan, respectively To determine the production capacity cumulative value by cumulatively adding the production capacity from the first day of the above period to the day, and complete the production of all the units included in each unit group by the above production completion upper limit day The number of production units obtained by adding the required total number of production units for each day from the first day of the above period to the relevant day, while calculating the required total number of production units for each day A process for obtaining a product value; a process for obtaining a cumulative operation rate indicating the ratio of the cumulative number of production units to the cumulative production capacity for each day from the first day of the period to the end of the period; A computer program for executing a process for setting a production plan for each day so that the cumulative occupancy rate on the day showing the peak in the period is substantially equal to the occupancy rate from the first day of the period to the day showing the peak. Computer readable recording medium.

<Structure 7> In the production plan leveling method according to Structure 6, the day after the peak is set as a new production plan target period, and the production plan of each day is set until the end of the period. A computer-readable recording medium that records a computer program that repeats a process of setting a computer.

<Configuration 8> In the production plan leveling method described in Configuration 1, information indicating a production plan obtained as a result of the leveling is stored in a server, and is viewed from a predetermined terminal in a sales department via a network. A production plan leveling method characterized by the following.

<Structure 9> In the production plan leveling method described in Structure 8, when an input of a production completion upper limit date of a new unit group is received from a predetermined terminal of the sales department via a network, the production plan of each day is received. Resetting the production schedule.

<Structure 10> In the production plan leveling method described in Structure 1, when the upper limit days of production completion are concentrated on a specific day, the upper limit days of production completion on the specific day are temporarily dispersed in an allowable range in advance. And then setting a production plan by arranging all unit groups in order of the temporarily completed production completion upper limit date.

<Structure 11> The production plan smoothing method according to Structure 10, wherein a production period from a production start date to a production completion upper limit date is extended.

<Structure 12> In the production plan leveling method according to Structure 10, the difference between the actual shipping date determined to be after a predetermined period from the upper limit date of the production completion and the temporarily distributed temporary shipping date is minimized. As described above, the production plan leveling method is characterized by temporarily dispersing the production completion upper limit date.

<Structure 13> In the production plan leveling system described in Structure 5, when the upper limit of production completion day is concentrated on a specific day, before executing the process for setting the production plan, the specific A production plan setting means for temporarily distributing the production plan upper limit date within an allowable range, and then arranging all unit groups in the order of the production completion upper limit date.

<Structure 14> In the production plan leveling system according to Structure 13, the production plan setting means extends the production period from the production start date to the production completion upper limit date. .

<Structure 15> In the production plan leveling system according to Structure 13, the production plan setting means includes an actual shipping date determined to be a predetermined period after the upper limit date of the production completion and a provisionally distributed temporary shipping date. A production plan leveling system, wherein the upper limit date of the production completion is provisionally dispersed so that the difference between the two is minimized.

<Structure 16> When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date must be produced during a period to be subjected to a production plan, production of all units included in each unit group is performed. The production completion upper limit date that must be completed is determined, and in order of this production completion upper limit date,
A process of arranging all the unit groups and a production process in which the daily production capacity is determined from the first day to the last day of the period covered by the production plan, and the production capacity is cumulatively added for each day from the first day of the period to the day. A process for determining the ability cumulative value;
Assuming that the production of all units included in each unit group has been completed by the above-mentioned production completion upper limit date, the required total number of production units per day is calculated, and the required total production units per day from the first day of the period to the relevant day A process of obtaining a cumulative value of the number of production units obtained by cumulatively adding, and a process of calculating a cumulative operating rate indicating a ratio of the cumulative number of production units to the cumulative value of the production capacity for each day from the first day of the period to the end of the period, A process of setting a production plan for each day so that the cumulative occupancy rate is the same as the occupancy rate from the first day of the period to the day of the peak, the cumulative occupancy rate of the peak day in the period. A computer program that causes a computer to execute.

<Structure 17> In the computer program described in Structure 16, the day after the peak is set as a target period of a new production plan, and the production plan of each day is set until the end of the period. A computer program that causes a computer to execute processing that repeats processing.

<Structure 18> In the computer program described in Structure 16, when the upper limit days of production completion are concentrated on a specific day, the upper limit days of production completion on the specific day are temporarily dispersed in an allowable range in advance. A computer program that causes a computer to execute a process of setting a production plan by arranging all unit groups in the order of a production completion upper limit date.

<Structure 19> A computer program for causing a computer to execute a process of extending a production period from a production start date to a production completion upper limit date in the computer program described in Structure 16.

<Structure 20> In the computer program described in Structure 16, the difference between the actual shipping date determined to be a predetermined period after the upper limit date of the production completion and the temporarily distributed temporary shipping date is minimized. A computer program that causes a computer to execute a process of temporarily distributing the upper limit date of production completion.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below using specific examples. FIG. 1 is a system block diagram for implementing the production plan leveling method of the present invention. When a house is ordered, a production plan for assembling units such as a room unit, a balcony unit, and an entrance unit is set for each house. These units have the same delivery date for the same residence. In the figure,
The unit group 1 for one house is surrounded by a broken line frame, and is displayed on the time axis 2 in order of the production completion upper limit date. The production completion upper limit date corresponds to a production termination date at which at least all units must be produced. Each unit group is planned to be produced within a certain period before the production completion upper limit date.

The host computer 10 shown in the figure is used for this production plan. This host computer 10
May directly control the production line of the factory, or may be used by a manager for production planning to create data or data for controlling the production line of the factory. In this figure, functional blocks of a program operated by the host computer 10, data necessary for the operation, and the like are displayed in a frame indicated by a chain line. That is, the delivery date input means 4, the unit group arrangement means 5, the production capacity accumulation means 6, the production unit number accumulation means 7, the cumulative operation rate calculation means 8, and the production plan setting means 9 are provided for production management by the host computer 10. . For these calculations, the production plan database 11 stored in the storage unit of the host computer is used. The obtained result is transferred to a computer for controlling the production factory, printed by the printer 12, and distributed to each person in charge of the production line of the factory.

The delivery date input means 4 is used for inputting an identification number, a unit name, a delivery date, and the like of the house that has received the order when the house is received.
It consists of a display and a keyboard. The unit group arrangement means 5 has a function of arranging all the unit groups in the order of the production completion upper limit date based on the production completion upper limit date at which the production of all units included in each unit group must be completed. . These arrangements are performed on the memory of the host computer 10. Production capacity accumulation means 6
Has a function of obtaining a daily production capacity from the first day to the last day of the period to be subjected to the production plan, and cumulatively adding the production capacity from the first day of the period to the day on a daily basis.

The production unit number accumulating means 7 determines the required total number of production units per day assuming that the production of all units included in each unit group is completed by the upper limit date of each production completion, and calculates the required total number of production units per day. It has a function to accumulatively add the required total number of production units. The result is shown in FIG.
This will be described with reference to FIG. The cumulative operating rate calculation means 8 has a function of calculating the ratio of the cumulative number of production units to the cumulative production capacity every day from the first day of the period to the last day of the period. The result will be described later with reference to FIG. The production plan setting means 9 finds a day on which the cumulative occupancy rate shows a peak in the period, and sets the production plan from the first day of the period to the day on which the peak shows the peak so that the production plan becomes equal to the occupancy rate on the day on which the peak shows. It has a leveling function. The production plan database 11 stores a daily production capacity determined in advance for each factory, a leveled production plan calculated by the production plan setting means 9, and the like.

FIG. 2A shows the result of the arithmetic processing by the unit group arranging means 5, and FIG. 2B shows the result of the processing by the production capacity accumulating means 6, the number of production units accumulating means 7 and the cumulative operating rate calculating means 8. (C) is a graph showing the relationship between the production capacity and the required number of production units.

For example, as shown in FIG.
Suppose that we received an order for five types of property, E. In this case, the property A has already started production, and the production of the remaining 16 units is required. Property B has 10 units, Property C has 20 units, Property D has 18 units,
Property E is scheduled to produce 20 units.
In this case, the property A has to complete the production one day later, that is, the next day, based on the day on which the production plan leveling process is executed, for example, today. Properties B and C must complete production two days later. Property D is 4 days later,
Property E must complete production in 5 days.

Data of this content is input to the computer 10 by the delivery date input means 4 shown in FIG. The unit group arrangement means 5 arranges the property names in order of the production completion upper limit date. Next, as shown in (b) of the figure, the day when the production plan leveling process is executed, for example, the first day of the period is set to 0,
Find the production capacity of each day until the day after. The production capacity of each day is not always the same due to the delivery of materials or the staffing. Since the production capacity is stored in the production plan database 11, it may be referred to. further,
The total number of specific production units is displayed in order from the first day (today) of the period indicated as 0, one day, two days, three days, etc., in accordance with the production completion upper limit day. One day later, the production of property A must be completed, so the number of production units on that day is 16, and two days later, production of properties B and C must be completed, so the number of production units (target)
Is 30, which is the sum of both units.

Here, the production capacity accumulating means 6 accumulates the production capacity by sequentially adding the production capacity every day. Since the production capacity on the first day of the period indicated by 0 is 14, the accumulated production capacity is 14, and the production capacity after 1 day is 14.5, and thus 28.5 is added to the production capacity on the day indicated by 0. Is the cumulative value of the production capacity. Similarly, the accumulated value of each day is obtained. The production unit number accumulating means 7 accumulates, on a daily basis, the target number of production units for which production is actually requested. The accumulation method is exactly the same as the accumulation of production capacity. Therefore, as shown in this figure, from the first day of the period to 5 days later, 0,
16, 46, 46, 64, and 84. As shown in (c) of the figure, there is a great difference between the specific production capacity and the specific number of production units ordered.
In the figure, the height of the hatched bars is the production capacity. The numerical value displayed on the head of the bar is the target number of production units.

FIG. 3A is a bar graph showing the change in the cumulative number of production units, and FIG. 3B is a bar graph showing the cumulative production capacity. In the example shown in FIG. 2A, the production capacity is gradually increased by a constant amount with each passing day. On the other hand, the cumulative value of the number of production units that have received a specific order increases non-uniformly as shown in FIG. If there is a difference in production capacity on each day and the number of production units ordered differs from day to day, the production plan cannot be leveled by a simple method. However, if the calculation is complicated, it is not suitable for real-time processing by a computer. Therefore, in the present invention,
The following processing is executed. First, the cumulative operating rate calculation means 8 calculates the ratio of the cumulative value of the number of production units to the cumulative value of the production capacity on each day. The result is the cumulative operating rate shown in the rightmost column of FIG.

FIG. 4 is an operation flowchart showing a procedure from the input of the delivery date to the execution of the cumulative operating rate calculation process. First, in step S1, a parameter D is initialized. The parameter D indicates the value of the day in the leftmost column in FIG. Next, in step S2, the delivery date input means 4 receives an input of data as shown in FIG. In step S3, the unit group arrangement means 5 arranges the input data in the order of the production completion upper limit date. In step S4, the production capacity accumulating means 6 calculates the accumulated value of the production capacity from the first day of the period. In step S5, the production unit number accumulation means 7 calculates the accumulated value of the production unit number from the first day of the period.

In step S6, the cumulative operating rate calculating means 8 calculates the cumulative operating rate by dividing the cumulative value of the number of production units by the cumulative value of the production capacity. In step S7, the parameter D is advanced by one. That is, the process proceeds to the next day. In step S8, it is determined whether the processing has been performed up to the end of the period. If the processing has not been completed to the end, step S2
And the processing from step S2 to step S7 is repeated. Then, from the first day to the last day of the period, the number of production units, the cumulative value of the production capacity, the cumulative value of the number of production units, and the cumulative operation rate are obtained. As a result of the above processing, data having contents as shown in FIG. 2B is obtained.

FIG. 5A is a graph showing a change in the cumulative operation rate, and FIG. 5B is an explanatory diagram showing the number of production planning units after leveling. As shown in FIG. 5A, the cumulative operation rate is
It peaks two days after the first day of the period. In other words, of the five days after the current leveling is attempted, the day two days after the first day of the period indicates the highest cumulative operation rate. In this case, the production plan is set so that the operation rates at the first day, one day and two days after the period are equal to the cumulative operation rate at two days after the peak day. Specifically, as shown in FIG. 2, since the cumulative operation rate of the peak is 105.75%,
The first day of the period and the production capacity one day later are 105.7, respectively.
The value rounded by 5% is used as the number of production planning units for each day. The result is shown in FIG. The number of production planning units is 15 units on the first day of the period, 15 units after 1 day, and 16 units after 2 days. With such an operating rate, the operating rates during these three days are almost equal. The three-day production plan was thus leveled.

FIG. 6 is an operation flowchart of the production plan setting means 9. First, in step S11, FIG.
The peak of the cumulative operation rate is detected from the data as shown in FIG. Then, in step S12, the parameter D
(The value of the day in the leftmost column in FIG. 2B) is set to an initial value. The initial value is 0. Next, in step S13, the number of production planning units, that is, the number of production units per day is calculated as
Calculate so that production capacity x peak operation rate. Next, in step S14, D is advanced by one day. Step S15
Then, it is determined whether or not this calculation has been performed until the day when the operation rate shows a peak. That is, the processes of steps S13 and S14 are repeated until the day when the operation rate reaches a peak. When this is completed, it is determined whether or not the processing has been completed up to the last day of the period for performing the leveling processing (step S1).
6). If not, the process returns to step S11.

FIG. 7 shows the result of recalculating the cumulative operating rate anew three days later as the leveling processing start date. In the first loop from step S11 to step S16 in FIG. 6, the leveling process shown in FIG. 5B is completed from the first day of the period to two days later. Next, in the second loop, 3
Perform processing after day. In this case, the cumulative operation rate after three days is recalculated. From the result, as shown in FIG. 7A, it can be seen that the peak after 5 days is 79.17%. FIG. 7B is a graph showing the cumulative operation rate of each day. Therefore, a leveling process is performed in a similar procedure so that the operation rate becomes equal to the peak five days later. The result is as shown in FIG. That is, the number of production planning units becomes 12 after 3 days, and the number of production planning units becomes 13 after 4 days and 5 days.

FIG. 8 (a) shows the result of the production plan leveling process, and FIG. 8 (b) is an explanatory diagram showing the operation rate of each day after the leveling process. The production plan setting means 9 shown in FIG. 1 outputs data having contents as shown in FIG. As shown in (b) of the figure, the operating rate of each day is first leveled to about 105% until two days after the cumulative operating rate reaches a peak. From 3 days to 5 days later, the operating rate has been leveled at about 80%. If the above processing is executed each time there is a change, addition, cancellation, or other event of the production plan, such leveling processing can be performed immediately. Since arithmetic processing is automatically performed by a computer, there is no load on skilled production management personnel. In this way, it is always possible to assemble the optimal production plan quickly and automatically.

In the above description, when an order for one house is received, a production plan is made in units of, for example, 15 units or 20 units. That is, the calculation example is introduced assuming that the man-hour required for the production of one unit is constant.
However, for example, actual units such as a room unit, a balcony unit, and an entrance unit cannot always be produced with the same man-hour. In comparison with an average unit, some units require a large number of production steps and some units require a small number of steps. So, actually,
It is advisable to use the number of converted units taking into account the man-hours of each unit. Specifically, for a standard unit, the number of units is set to 1, for a unit with a large number of man-hours, for example, 1.2, and for a unit with a small number of man-hours, for example, 0.9. And As described above, the number of units is represented by a natural number, thereby realizing the production management in consideration of the man-hour difference. In order to perform such man-hour conversion, for example, data indicating production man-hours for each unit is prepared. In the case of a kitchen unit, a kitchen set,
It is composed of multiple parts such as shelves and sashes. In this case, data indicating the man-hour required for the attachment is prepared for each component. By integrating this data, the man-hour of the unit is obtained.

FIG. 9 is an explanatory diagram showing an application example of the present invention. In the figure, the host computer 10 shown in FIG. 1 is connected to a server 20. The server 20 stores an information file 21 written from the host computer 10 and indicating a production plan obtained as a result of leveling. The information file 21 may be stored in a storage device built in the server 20, or may be stored in a storage device external to the server 20. Although the format of this information file 21 is arbitrary, for example, FIG.
Any content as shown in FIG. The server 20
It is connected to a terminal 23 in the sales department via a network 22. Therefore, the salesperson can use the terminal 23 of the sales department to browse the information file 21 at any time. According to the present invention, it is preferable that a request from each sales department be reflected in a production plan in real time. That is, as shown by the arrow 24, the terminal 23 of the sales department
The host computer 10 receives the request from the host computer 10 and makes a trial calculation of the leveling process. If the leveling process is possible, the host computer 10 receives the request on the spot. At the same time, the production plan obtained as a result of the leveling is stored in the server 20 and the network 2
2, it is preferable to be able to browse from a predetermined terminal 23 such as a sales department. Thus, the sales department can receive additional orders, changes in order details, and the like from customers while constantly browsing the latest production plan and recognizing the content. Therefore, it is possible to prevent the sales department from accepting additional orders that cannot be handled or changes in the order contents. Furthermore, the daily production capacity at a production factory is not always constant. The difficulty of the real-time production plan leveling method under the condition of different daily production capacity could be solved.

FIG. 10 is an explanatory diagram for explaining a modification of the present invention. The figure shows the schedule on the horizontal axis. House A, House B,
This is a graph in which production schedules are indicated by arrows with respect to orders of three houses called House C, and the names of the houses are indicated on shipping dates. The upper half of (a) shows the schedule before performing the shipping date leveling process. For example, in the case of House A, assembly production is performed in two days, one day and two days.
Ships on the 7th. In the case of Houses B and C, production will take place in two days, three days and four days, and will be shipped on the 9th. The lower half of (a) shows the schedule after the shipping date leveling process. If you try to level the production plan while fixing the shipping cost and fixing the lead time from the production completion date to the shipping date, if the shipping date is concentrated on a specific day, sufficient leveling will be performed. May not be easy. In this embodiment, when shipping dates are concentrated, one of the shipping dates is provisionally moved within an allowable range. The shipping date depends on the customer's request and cannot be moved without permission. Therefore, in the calculation process by the computer, the shipping date is temporarily moved, the leveling process is performed, and the calculation date is restored. Processing such as selection of a provisional shipping date is executed by, for example, the production plan setting means 9 in FIG.

In the plan indicated as (before processing) in FIG. 10A, the shipping dates of House B and House C are concentrated on the 9th. It is possible to perform leveling processing in such a state,
In this example, the shipping date of either House B or House C is advanced to eight days. In the calculation for leveling processing,
The leveling process is performed after shifting the shipping date of House B one day before. As a result, as described later, the production plan can be further leveled. In this example, the lead time from the upper end date of production to the date of shipment until the date of shipment is 3 days in this example. When the shipping date of House B is shifted forward by one day, the upper limit of production completion is also shifted forward by one day, and the production start date is simultaneously shifted forward by one day. The production schedule date for House B is advanced from the third and fourth days to the second and third days.
For the actual shipment, 8 pieces completed on the 3rd
Ship it on the 9th instead of the day.

The reason why the shipping date is temporarily moved is to temporarily disperse the upper limit date of production completion within an allowable range. This is because the calculation model can be prevented from becoming complicated by performing the arithmetic processing according to the rule that the lead time between the shipping date and the production completion date is constant. In the example shown in (b), the shipping dates of House A and House B are concentrated on the seventh day. For this reason, the production plan overlaps the first and second days. In this case, if the production plan of House A and the production plan of House C are shifted one day before while the production plan of House B is kept as it is, the processing is exactly the same as that of (a). It is not impossible to shift the upper limit of production completion date of House B one day later, as indicated by the dashed arrow pointing left in the figure. This is because, for a very small part of the large number of properties, the lead time from the upper limit of production completion to the date of shipment may be reduced to two days in some cases. Of course, this may be an exceptional measure.

In the example of (c), the shipping dates of House B and House C overlap on the 9th. At this time, the shipping date of House B is shifted to eight days. In addition, the production start date is shifted forward while the production completion upper limit date of House B remains unchanged. as a result,
The production period from the production start date to the production completion upper limit date has been extended. As a result, the production process of House B is decentralized,
The leveling process can be performed as a whole. Next, a specific calculation method and its effects will be described with reference to the following drawings.

FIG. 11 is an explanatory diagram showing an example of a production plan to be leveled. The format of this figure is the same as the example described with reference to FIG. 2 is different from FIG. 2 in the content of the upper limit date of the production completion. As shown in (a) of the figure, the production completion upper limit days of the property names C and D are all four days. Although not shown, the shipping dates are concentrated on the same day. Under such conditions, the production capacity accumulation and the cumulative operation rate similar to those shown in FIG. 2B will be obtained.
In addition, the portion indicated as the number of production units shows the operation rate when it is assumed that all the production units targeted by the production capacity on that day have been produced. The unit of operation rate is%.
That is, on the first day, the target value is 16 and the production capacity is 14.5.
Therefore, the production operation rate becomes 110%. On the second day, since the target value is 10 and the production capacity is 15, the operation rate becomes 67%. On the fourth day, since the target value is 38 and the production capacity is 16, the operation rate is 238%. As described above, if all the production units targeted by the production capacity of the day are produced, a large variation in the operation rate occurs. In the leveling process described with reference to FIGS. 2 to 9, the peak of the cumulative operation rate is found and leveled. In this example, since the 59% peak on the second day, the occupancy rates on the first and second days are averaged, and 91% on the fifth day.
Because of the peak, the occupancy rate from the third day to the fifth day was determined.

FIG. 12 is an explanatory diagram of an example in which the above-described production plan leveling process is executed after shifting the level of the production completion upper limit date and leveling. As shown in FIG.
In the production schedule shown in (a), the upper limit date of the production completion of the property name C is advanced to three days. In this state, FIG.
FIG. 12B shows the result of performing the same leveling processing as in FIG. As shown in FIG. 12 (b), when it is assumed that all the production units targeted by the production capacity on that day have been produced, the operation rate is 67% on the second day, 110% on the other days, and 129.
%, 113%, and 121%. If this is leveled, the peak of the cumulative operating rate will be on the fifth day, so that the operating rates on all days need only be set to 91%.
As the number of portions showing the peak of the cumulative operating rate decreases within the range in which the leveling process is performed, the leveling process can be more uniformly performed as a whole. Moreover, this calculation can be performed extremely mechanically, and the leveling process described with reference to FIGS. 2 to 9 can be performed only by adding simple pre-processing and post-processing.

When the production date is leveled by shifting the shipping date, the actual shipping date is as planned, so the actual shipping date and the tentative shipping date for performing the leveling calculation of the production plan are set. The smaller the gap between the two, the easier the production plan will be. Therefore, when many shipping dates are concentrated and there are many shipping dates to be shifted, the difference between the actual shipping date and the tentative shipping date is calculated, and the accumulated value becomes the minimum value.
It is advisable to determine and distribute the provisional shipping date. If there are multiple solutions that have the same cumulative occupancy rate, the maximum value of the difference between the provisional shipping date and the actual shipping date is compared, and the solution with the smaller maximum value of the difference is adopted. Good to do.

FIGS. 13A and 13B are explanatory diagrams of a schedule for explaining another specific example. FIG. 13A shows a state before the shipping date leveling process, and FIG. 13B shows a state after the shipping date leveling process. . As shown in (a) of the figure, the shipping date is determined to be 5 days, 7 days, 7 days, and 10 days for the four properties of House A, House B, House C, and House D, respectively. For this example, the shipping date is shifted and leveled within a range of 6 days from 5 days to 10 days. In addition, as a condition, only the advance is allowed. The planned allocation period changes depending on the shipment date of House B and House D.
That is, the production start date and the production completion upper limit date are shifted forward. Based on the following figure, the leveling results of the production plan are compared with and without the shipping date.

FIG. 14 is an explanatory diagram for explaining the production capacity, the cumulative operating rate, and the like when the leveling process is not performed by moving the shipping date. In this case, a production plan is drawn up before the shipping date is equalized. A to D residences are all 15 units. It is assumed that today = 2 days, and the production plan will be finalized today. In the manner already described, the daily production capacity is determined, and the total number of units to be produced by the upper limit of the production completion date (in this example, the day before the shipping date) is determined. Next, the respective accumulations are obtained. Finally, the cumulative ratio to the production capacity is calculated for each day. This completes the calculation of (a).

In this way, the production peak is obtained, and leveling up to the production peak is performed. First, leveling in the range from day 0 to day 5 is performed. Multiply the peak operation rate (45.5%) by the daily production capacity to determine the number of planned production units per day. Furthermore, the units of the actual property are assigned in order of priority to the number of daily production planning units. Thus, the result of (b) is obtained.

FIG. 15 is an explanatory diagram showing an allocation result when the leveling process is not performed by moving the shipping date. The above process is repeated for the range from 5th to 9th for the leveling process of the days after the peak. The production peak is detected by (a). Further, leveling up to the production peak is performed by (b). From the above results, the allocation result shown in (c) is obtained.

FIG. 16 is an explanatory diagram for explaining the production capacity, the cumulative operating rate, and the like when the leveling process is performed by moving the shipping date. Here, the production plan leveling is performed after the shipping date leveling process as described above. FIG. 17 is an explanatory diagram showing an allocation result when the leveling process is performed by moving the shipping date. As shown in (a) of the figure, the process is completed because the production peak is the last one and there is no house to be leveled after the peak. The allocation result is as shown in (c), and the leveling is promoted as compared with the case of FIG. 15 (c).

FIG. 18 is an explanatory diagram for explaining the production capacity, the cumulative operating rate, and the like when the leveling process is performed by extending the production period. In the above example, if the production period from the production start date to the production completion upper limit date is extended, the following results are obtained. FIG. 19 is an explanatory diagram illustrating an allocation result when the leveling process is performed by extending the production period. As shown in FIG. 18 (a), there are two production peaks, but if leveling is performed as shown in FIG. 18 (b) and FIGS. 19 (a) and (b), it will be shown in FIG. 19 (c). Thus, it can be seen that the leveling is more fully performed than in the example of FIG.

Note that the functional blocks shown in FIG. 1 do not necessarily need to operate according to the above-described flowchart as long as they have similar functions. Further, each functional block may be configured by a separate program module, or may be configured by an integrated program module. Further, all or a part of these functional blocks may be configured by hardware using a logic circuit. Each program module may be operated by being incorporated into an existing application program, or may be operated as an independent program. Further, the computer program for realizing the present invention as described above can be recorded on a computer-readable recording medium such as a CD-ROM, installed, and used. It can also be downloaded and used in the memory of a computer via a network.

[0056]

As described above, the operation of leveling the cumulative operating rate on the day when the cumulative operating rate shows the peak to become the operating rate from the first day of the period to the day showing the peak is repeated. If the production plan leveling process is performed during the following period, irregularities in the production plan can be automatically and promptly and reliably reduced using a computer. Therefore, even when daily production capacities are different from each other and shipment is concentrated on a specific day, decentralization of production plans according to production capacities can be easily realized. In particular, it is possible to quickly review the production plan and execute the leveling process in real time with respect to interrupts, changes, cancellations, and the like that frequently occur in the case of build-to-order manufacturing. Therefore, just-in-time production management is promoted, product inventory is minimized,
This contributes to the reduction of inventory space and the reduction of inventory management man-hours, and the effect of improving the efficiency of collecting accounts receivable.

[Brief description of the drawings]

FIG. 1 is a system block diagram for implementing a production plan leveling method of the present invention.

FIG. 2 (a) shows the result of the arithmetic processing by the unit group arrangement means 5, FIG. 2 (b) shows the result of the processing by the production capacity accumulating means 6, the number of production units accumulating means 7, and the cumulative operating rate calculating means 8, c) is a graph showing the relationship between the production capacity and the required number of production units.

FIG. 3A is a bar graph showing the change in the cumulative value of the number of production units, and FIG. 3B is a bar graph showing the cumulative production capacity.

FIG. 4 is an operation flowchart showing a procedure from input of a delivery date to execution of a cumulative operating rate calculation process.

FIG. 5A is a graph showing a change in a cumulative operating rate,
(B) is an explanatory view showing the number of production planning units after leveling.

FIG. 6 is an operation flowchart of the production plan setting means 9;

FIG. 7 shows a result of recalculating the cumulative operating rate again with three days later as the leveling processing start date.

FIG. 8A shows a result of a production plan leveling process;
(B) is an explanatory view showing an operation rate of each day after leveling processing.

FIG. 9 is an explanatory diagram showing an application example of the present invention.

FIG. 10 is an explanatory diagram for describing a modified example of the present invention.

FIG. 11 is an explanatory diagram illustrating an example of a production plan to be subjected to leveling processing.

FIG. 12 is an explanatory diagram of an example in which the above-described production plan leveling process is executed after shifting the level of the production completion upper limit date and leveling.

13A and 13B are explanatory diagrams of a schedule for explaining another specific example, in which FIG. 13A shows a state before a shipping date leveling process, and FIG.
Is the state after the shipping date leveling process.

FIG. 14 is an explanatory diagram for explaining a production capacity, a cumulative operating rate, and the like in a case where leveling processing by moving a shipping date is not performed.

FIG. 15 is an explanatory diagram showing an allocation result in a case where leveling processing by shipping date movement is not performed.

FIG. 16 is an explanatory diagram for explaining a production capacity, a cumulative operation rate, and the like when the leveling process is performed by moving a shipping date.

FIG. 17 is an explanatory diagram showing an allocation result in a case where leveling processing by shipping date movement is performed.

FIG. 18 is an explanatory diagram for explaining a production capacity, a cumulative operation rate, and the like when a leveling process is performed by extending a production period.

FIG. 19 is an explanatory diagram showing an allocation result when a leveling process is performed by extending a production period.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Unit group 2 Time axis 4 Delivery date input means 5 Unit group arrangement means 6 Production capacity accumulation means 7 Production unit number accumulation means 8 Cumulative operation rate calculation means 9 Production plan setting means 10 Host computer 11 Production plan database 12 Printer

Claims (20)

[Claims] When a plurality of unit groups, each of which includes a plurality of units having the same delivery date, must be produced during a period to be subjected to a production plan, production of all units included in each unit group is completed. Determine the production completion upper limit day that must be established, arrange all the unit groups in order of this production completion upper limit date, and determine the daily production capacity from the first day to the end of the period to be subjected to the production plan, Every day, the production capacity is obtained by cumulatively adding the production capacity from the first day of the period to the day, and it is necessary to determine that the production of all the units included in each unit group is completed by the upper limit of the production completion date. The total number of production units is determined, and the cumulative number of production units obtained by cumulatively adding the required total number of production units from the first day of the period to the day is determined for each day. From the first day to the end of the period, a cumulative operating rate indicating the ratio of the cumulative number of production units to the cumulative production capacity for each day is calculated for each day, and the cumulative operating rate at which the cumulative operating rate peaks during the period is calculated. A production plan is set for each day so as to be substantially equal to the operation rate from the first day of the period to the day showing the peak. 2. The production plan leveling method according to claim 1, wherein the operating rate of the day on which the cumulative operating rate shows a peak, and the production capacity of each day from the first day of the period to the day on which the peak shows the peak. Is set to the upper limit of the production capacity of each day. 3. The production plan leveling method according to claim 1, wherein a day after the peak is set as a period to be subjected to a new production plan, and the production plan of each day is set until the end of the period. A production plan leveling method characterized by repeating a setting process. 4. The production plan leveling method according to claim 1, wherein the process of manufacturing each part of the product with a predetermined delivery date is one unit, and the number of units is one when the man-hour of the process is a standard value.
A production plan leveling method, wherein the number of units is a natural number of 1 or more when the number is equal to or more than a standard value, and the number of units is a natural number of 1 or less when the number is less than the standard value. 5. When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date have to be produced during a period to be subjected to a production plan, production of all units included in each unit group is completed. A unit group arranging means for arranging all the unit groups in the order of the production completion upper limit day which defines the production completion upper limit day, and the daily production from the first day to the end of the period to be subjected to the production plan. A capacity determining means for determining a capacity, a production capacity accumulation value obtained by cumulatively adding a production capacity from the first day of the period to the day of the period, and all units included in each unit group by the production completion upper limit date. The required total number of production units per day is determined assuming that the production is completed. A production unit number accumulating means for calculating the production unit number accumulated value, and a cumulative operation rate for calculating a cumulative operation rate indicating a ratio of the production unit number accumulated value to the production capacity accumulated value for each day from the first day of the period to the end of the period. Rate calculating means, and a production plan for each day such that the cumulative operating rate at which the cumulative operating rate shows a peak in the period is substantially equal to the operating rate from the first day of the period to the day showing the peak. And a production plan setting means for setting the production plan. 6. When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date have to be produced during a period targeted for a production plan, the production of all units included in each unit group is completed. The process of arranging all the unit groups in order of the production completion upper limit day which must be performed and the production completion upper limit date, and the daily production capacity is defined from the first day to the end of the period to be subjected to the production plan, respectively. A process of obtaining a cumulative production capacity value by cumulatively adding the production capacity from the first day of the period to the relevant day for each day; and completing the production of all the units included in each unit group by the production completion upper limit date. As well as obtaining the required total number of production units per day, the production unit number cumulative value obtained by cumulatively adding the required total number of production units from the first day of the period to the relevant day for each day A process for obtaining a cumulative operating rate indicating a ratio of the cumulative number of production units to the cumulative production capacity for each day from the first day of the period to the end of the period; and the cumulative operating rate peaks during the period. A computer program for executing a process for setting a production plan for each day such that the cumulative utilization rate on the day indicating the period is substantially equal to the utilization rate from the first day of the period to the day representing the peak. Possible recording medium. 7. The production plan leveling method according to claim 6, wherein a period after the peak day is set as a target period of a new production plan, and the production plan of each day is set until the end of the period. A computer-readable recording medium that records a computer program that repeats a setting process. 8. The production plan leveling method according to claim 1, wherein information indicating the production plan obtained as a result of the leveling is stored in a server, and is browsed from a predetermined terminal in a sales department through a network. A production plan leveling method. 9. The production plan leveling method according to claim 8, wherein when an input of a production completion upper limit date of a new unit group is received from a predetermined terminal of the sales department via a network, the production plan of each day is changed. A production plan leveling method characterized by performing resetting. 10. The production plan leveling method according to claim 1, wherein when the upper limit day of the production completion is concentrated on a specific day, the upper limit day of the production completion on the specific day is temporarily dispersed in an allowable range in advance. A production plan leveling method characterized by setting a production plan by arranging all unit groups in the order of the temporarily completed production completion upper limit date. 11. The production plan leveling method according to claim 10, wherein a production period from a production start date to a production completion upper limit date is extended. 12. The production plan leveling method according to claim 10, wherein a difference between an actual shipping date determined to be after a predetermined period from the upper limit date of the production completion and a provisionally distributed temporary shipping date is minimized. To
A production plan leveling method characterized by temporarily dispersing production upper limit dates. 13. The production plan leveling system according to claim 5, wherein when a production completion upper limit day is concentrated on a specific day, before executing a process for setting a production plan, the production plan upper limit date is set in advance. A production plan leveling system, comprising: a production plan setting means for temporarily distributing the production plan upper limit day within an allowable range and then arranging all unit groups in order of the production completion upper limit date. 14. The production plan leveling system according to claim 13, wherein the production plan setting means extends a production period from a production start date to a production completion upper limit date. 15. The production plan leveling system according to claim 13, wherein the production plan setting means determines a difference between the actual shipping date determined to be after a predetermined period from the upper limit date of the production completion and the temporarily distributed temporary shipping date. A production plan leveling system, wherein the production completion upper limit date is temporarily dispersed so that the difference is minimized. 16. When a plurality of unit groups obtained by assembling a plurality of units having the same delivery date have to be produced during a period targeted for a production plan, the production of all units included in each unit group is completed. The process of arranging all the unit groups in order of the production completion upper limit day which must be performed and the production completion upper limit date in order, and defining the daily production capacity from the first day to the end of the period to be subjected to the production plan, respectively A process of obtaining a cumulative production capacity value by cumulatively adding the production capacity from the first day of the period to the relevant day for each day; and completing the production of all the units included in each unit group by the production completion upper limit date. The total number of production units obtained by summing up the required total number of production units for each day from the first day of the period to the day, while obtaining the required total number of production units for each day From the first day of the period to the end of the period, a process of obtaining a cumulative operating rate indicating the ratio of the production unit number cumulative value to the production capacity cumulative value for each day, A computer program for causing a computer to execute a process of setting a production plan for each day such that the cumulative occupancy rate on a peak day is substantially equal to the occupancy rate from the first day of the period to the peak day. 17. The computer program according to claim 16, wherein a day after the peak is set as a target period of a new production plan, and a production plan is set for each day until the end of the period. A computer program that causes a computer to execute a process that repeats. 18. The computer program according to claim 16, wherein when the upper limit day of production completion is concentrated on a specific day, the upper limit day of production completion is provisionally dispersed in an allowable range in advance before the production A computer program for causing a computer to execute a process of setting a production plan by arranging all unit groups in the order of completion upper limit date. 19. The computer program according to claim 16, wherein the computer executes a process of extending a production period from a production start date to a production completion upper limit date. 20. The computer program according to claim 16, wherein a difference between an actual shipping date determined to be a predetermined period after the upper limit date of the production completion and a temporarily distributed temporary shipping date is minimized.
A computer program that causes a computer to execute a process of temporarily distributing the upper limit date of production completion.