JPH0930616A - Inventory managing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the occurrence of such inconvenience as excessive stock, inventory shortage or the like by correcting the standard read time on the basis of the actual value of the amount of object passage during the prescribed period of time accumulated in a database, and calculating the amount of object stock per unit period preset with the standard read time after the correction. SOLUTION: The values of the standard read time fed from an input device 101 and the amount of actual object passage are accumulated in a read time database 104 and a passage amount DB 103 with the aid of a control device 102. The control device 102 corrects the standard read time on the basis of the actual passage amount during the specified period accumulated in the read time database 104. The stock of objects per predetermined unit period is calculated with the standard read time which has undergone a correction. The obtained stock is fed to an output device 105 and thereupon printing is carried out, and thereby avoiding such occurrence as excessive stock or inventory shortage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inventory quantity management device for managing the inventory quantity of each process in a production system for producing a predetermined article through a plurality of processes, and particularly to production bases and sales offices all over the world. The present invention relates to an inventory amount management device used for production management work of a company having a base.

[0002]

2. Description of the Related Art Conventionally, in a production system for producing a predetermined article through a plurality of manufacturing processes and transportation processes, a fixed lead time has been set to manage the inventory amount in each process. . Here, the lead time is the article transfer time between steps and the production required time in each step. The article transfer time may be referred to as a distribution lead time, and the production required time may be referred to as a production (manufacturing) lead time. .

In the conventional inventory management using this lead time, as a process procedure and transportation means, the total of manufacturing cost and physical distribution cost is minimized within a range satisfying a delivery date to a customer, and a sales opportunity is not lost. As a lead time required when selecting items and determining the ordering time, safety stock amount, and upper limit stock amount, a fixed value is the value that is used most often among the lead times between each process and process. Set and order time by this set lead time,
The safety stock amount and the upper limit stock amount were decided.

By the way, recently, due to various factors such as manufacturing cost, the transfer of production to overseas is in progress. As the production transfer to overseas progresses, it becomes inevitable that sea transportation and air transportation will intervene between the manufacturing process and between the manufacturing process and the sales department.

[0005] In the case where such a shipping service or an air shipping service comes to intervene, in the transportation process on the assumption that the shipping service is used, the shipping service is used in order to meet the short delivery time request from the customer. There will be more cases. However,
When using airmail, the inventory holding amount set on the premise of using airmail will be excessive due to the use of airmail with a short transportation lead time. The same applies to process procedures with different durations. Such excess inventory causes business loss due to interest rate burden, management expense burden, and so on.

[0006]

However, in the conventional inventory management in each process, a standard process procedure and transportation means are selected for each process and each process, and the selected process procedure, Since the inventory quantity in each process is managed by using the lead time that is relatively frequently used in transportation means, it is not possible to respond to changes in the transportation lead time such as the change from shipping to airmail. There is a problem that it is not possible to avoid the occurrence of situations such as inventory or inventory breakage.

An object of the present invention is to provide an inventory management device capable of avoiding a situation such as excess inventory or inventory shortage and reducing business loss.

[0008]

In order to achieve the above object, the present invention provides a standard product transfer time and a standard lead time for the product transfer time between processes and the production time in each process. A standard lead time setting means set as, and a passing amount result database for measuring and accumulating the amount of articles passing between each process and in each process,
A calculation for correcting the standard lead time based on the actual value of the article passage amount for a predetermined period accumulated in the passage amount actual result database, and calculating the inventory amount of articles in a preset unit period by the corrected standard lead time. And processing means.

[0009]

The present invention does not regard each process or the lead time between processes as fixed, and reflects the process procedure and the usage record of the transportation means in the standard lead time, and the lead time that reflects this usage record is used. To use. The lead time that reflects this usage record can be considered as the time required to move between the virtual inventory positions regardless of the geographical distance between the sender and the destination, that is, the virtual lead time.

In this case, since the process procedure and the use record of the transportation means can be grasped by the amount of articles passing between each step and each step, specifically, the amount of articles passing between each step and each step can be calculated. Measure and correct the standard lead time based on the actual value of the passing amount of goods for a predetermined period,
The standard lead time after the correction, that is, the virtual lead time is used to calculate the inventory quantity of the articles in a preset unit period.

As a result, even if air transportation is frequently used as a means of transportation, which was originally assumed to be by sea due to market trends, a virtual lead time reflecting the actual results of a predetermined period is used, and therefore excess inventory is used. Can be avoided.

In this case, it is optimal to use the actual value of the article passing amount in the unit period immediately before the production plan is made. As a result, inventory management that reflects the latest market trends can be performed.

The virtual lead time of the present invention can be applied to all of the production process, distribution process and sales process of a company. Further, the lead time of the manufacturing process with a small lead time difference depending on the process procedure can be applied to both a case where a fixed lead time is used and a case where a virtual lead time is set using a weighted average of the usage records. Further, the application of the virtual lead time can be simplified by applying the virtual lead time only to the side closer to the market or the transportation process having a long lead time, not all the processes.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to an illustrated embodiment.

FIG. 1 is a block diagram showing an embodiment of the present invention. An input device 101, a control device 102 for performing arithmetic processing, a passing amount database (DB) 103, a lead time database (DB) 104, Output device 105
It is composed of

The input device 101 is for inputting each process for producing an article, the standard lead time between the steps, and the actual value of the passing amount of the article. The standard lead time and the actual value input from the input device 101 are input. The value of the article passing amount is controlled by the control device 102 by the lead time database 10
4 and the passing amount DB 103.

The lead time stored in the lead time database 104 is a virtual lead time calculated from the standard lead time input from the input device 101 and the actual value of the article passing amount and the standard lead time as described later. There are two types.

The output device 105 prints out the data accumulated in the lead time database 104 and the passing amount DB 103, and also prints out each process and the inventory amount between the processes calculated by the method described later.

FIG. 2 is a process model diagram for explaining the present embodiment. The process model is composed of four processes (1) 201 to (4) 204 and a process (1) corresponding to a transportation process. -2) There are three steps 210 to (3-4) 212.

Each process and each process have a different lead time (LT) corresponding to each process procedure, transportation means, transportation destination, and other options.

In FIG. 2, the shortest LT, the next short LT, the third short LT, ...

In this process model, the process (1) 20
1 and the step (1-2) 210 will be described in detail as an example, in the step (1) 201, there are two different types of apparatuses that process the step, and if one is the apparatus A and the other is the apparatus B, Although any of the devices can perform the necessary processing in step 201, there is a difference in performance such as processing speed, and therefore, there is a difference between the processing using the device A and the processing using the device B. Have different lead times. In FIG. 2, when the device A is used, the lead time is “shortest L
T = 10 days ", the case of using the device B is" next short LT = 15 "
This means that the process 201 has two different lead times.

Further, the step (1-2) 210 is the same as the step 2
Although it corresponds to a transportation process between 01 and 202, there are three types of transportation means: air mail, liner service, special shipping service, and their lead times are 2 days, 15 days, and 10 days, respectively. (1-2) 210 has three different lead times.

In addition to the above, as a lead time between processes, a lead time caused by a difference in ability of workers, a lead time caused when a plurality of production lines (transportation destinations) are possible, etc. are considered. To be

In the process model in this embodiment, it is possible to freely combine these processes and the processing procedure for each process and the shortest LT, the next short LT, the third short LT, ... The possible flow of each product is represented by a line.

Next, the data of the process model in FIG. 2 will be described with reference to FIGS.

The lead time for each step and means between steps is as follows:
It is input from the input device 101, and is stored as a standard lead time in the lead time database 104 by the control device 102 in a format as shown in FIG.

For example, in the step 201, the standard lead time data 301, 3 are the "shortest LT = 10 days" by the device A and the "next short LT = 15 days" by the device B as described above.
It is stored as 02.

The actual results of the amount of passage through the steps and between the steps are input from the input device 101 and accumulated in the amount-of-passage database 103 by the control device 102 in the format shown in FIG.

For example, the actual passage amount data 401 corresponding to the standard lead time data 301 and the actual passage amount data 4 corresponding to the standard lead time data 302 in FIG.
It is stored in the format 02.

Since passing of a process and products and articles between the processes occur at any time, the passing amount actual data changes sequentially.
Therefore, the measurement is performed in a predetermined management period unit, and the measurement value in the management period unit is stored. The model of this embodiment is managed on a daily basis.

Further, the virtual lead time calculated in this embodiment is stored in the lead time device 104 in the format as shown in FIG. 5 for each process and each process.

Next, the inventory quantity setting procedure based on each of the above data will be described with reference to the flowchart of FIG.

First, when the processing relating to inventory management is started, the control device 102 causes the planning unit period and the period set by the planner among the daily passing amount data accumulated in the passing amount database 103. The actual passing amount data corresponding to is collected, and is aggregated for each process, the process procedure corresponding to each process, the transportation means, the transportation destination, and the like (step 802).

When the planning unit period and the period set by the planner are designated, two actual passage amount data are collected.

Next, the control device 102 collects the standard lead time data between the processes and the processes stored in the lead time database 104, and the process calculated in step 802 and the process procedure corresponding to each process, Means of transportation
Select one of the actual transit volume data for each option, such as the transportation destination, and perform a weighted average for each option. This result is the virtual lead time and is stored in the lead time database 104 in the format of FIG. 5 (step 803).

Next, the safety stock amount is calculated (step 8).
04). In the calculation, the commonly used safety stock amount calculation formula “safety stock amount = average demand amount × √ (planning cycle + procurement LT)” is used.

Here, the average demand amount is any of the actual passage amount data calculated in step 802, or the data collected in a period newly set by the planner.

The planning cycle is a unit period for setting the inventory amount. In the present embodiment, an example is described in which the actual passing amount, which is the average demand amount, and the unit period for setting the inventory amount are the same.

The procurement LT is the virtual lead time calculated in step 803 and accumulated in the lead time database 104.

Next, it is judged whether or not all the safety stock amounts have been calculated for each process and each process (step 805). If completed, a series of processing is terminated, and if not, step 803. Then, the same processing is repeated.

Next, the case where the safety stock amount is calculated according to the present embodiment and the case where the safety stock amount is calculated only by the conventional fixed standard lead time will be described in comparison.

As the standard lead time, the second shortest lead time for each process and each process is adopted, and in the above-mentioned safety stock amount calculation formula, average stock amount = passage amount actual result, planning cycle = 5 days, procurement LT = When the safety stock amount is calculated by substituting the immediately preceding process or the lead time between the immediately preceding processes, it becomes as shown in FIG.

In this case, the value shown in FIG. 5 was used as the virtual lead time used in this example, and the value shown in FIG. 7 was used as the standard lead time.

In FIG. 8, the upper part shows the safety stock amount calculated by the conventional method, the next part shows the safety stock amount calculated by the method of this embodiment, and the lower part shows the reduction rate. As is clear from FIG. 8, it is shown that the effect of inventory reduction is greater for processes having a large lead time difference between process procedures and transportation means and between processes, for example, process (3) 203.

As described above, according to the embodiment of the present invention, it is possible to reduce the stock amount as compared with the case where a fixed lead time is used. In addition, the standard lead time is corrected based on the actual value of the passing amount of goods in a predetermined period, and the corrected standard lead time, that is, the safety stock amount of the goods in a preset unit period is calculated by the virtual lead time. , Even if air transportation is frequently used due to market trends, the means of transportation that was originally assumed to be by sea will use a virtual lead time that reflects the results of a predetermined period, so avoiding excess inventory be able to.

In this case, as the actual value of the passing amount of goods, by using the actual value in the unit period immediately before the time of making the production plan, it is possible to manage the inventory quantity reflecting the latest market trend.

[0048]

As is apparent from the above description, according to the present invention, it is possible to avoid a situation such as excess inventory or inventory shortage, and minimize the inventory holding amount.
It is possible to reduce management loss due to excess inventory.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a process model diagram used in an example.

FIG. 3 is an explanatory diagram showing an example of a lead time in the process model of FIG.

FIG. 4 is an explanatory diagram showing an example of a passing amount record in the process model of FIG.

5 is an explanatory diagram showing an example of a virtual lead time in the process model of FIG.

FIG. 6 is a flow chart showing an inventory quantity management procedure in the embodiment.

FIG. 7 is an explanatory diagram showing an example in which a standard lead time is set as a next short lead time.

FIG. 8 is an explanatory diagram showing a difference in the safety stock amount between the virtual lead time and the standard lead time.

[Explanation of symbols]

101 ... Input device, 102 ... Control device, 103 ... Passage amount database, 104 ... Lead time database, 1
05 ... Output device.

Claims (2)

[Claims] 1. An inventory quantity management device for managing an inventory quantity of each process in a production system for producing a predetermined article through a plurality of steps, wherein an article transfer time between the steps and a production required time in each step. A standard lead time setting means for setting a standard article transfer time and a production required time as a standard lead time, a passage amount result database for measuring and accumulating the article passage amount between each process and each process, and the standard lead time. And an arithmetic processing means for correcting the inventory amount of articles in a preset unit period by the corrected standard lead time based on the actual value of the article passage amount accumulated in the passage amount actual result database. An inventory management device characterized by comprising. 2. The inventory amount management apparatus according to claim 1, wherein the arithmetic processing unit corrects the standard lead time by weighted averaging the actual values of the article passage amount.