JP2782928B2 - Production sequence planning method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a product type in a case where production information is given in the form of a designated production period for each product type in a production line for producing various types of products. The present invention relates to a production sequence planning method for determining a production sequence between products.

[Conventional technology]

2. Description of the Related Art Conventionally, in an engine assembling line that produces many types of engines to be shipped to different vehicle assembly lines, a production order between product types is obtained by inputting a daily production volume of each product required from a shipping destination. (For example,
63-265791). For example, a product ratio Pi for each product type i is obtained from the input information, the obtained _Pi for the product type _i is fixed, and an expected production value X _ij in the order j is obtained by the following equation.

X _ij = P _i X _ij = X _ij-1 + P _i −δ _ij-1 where δ _ij-1 is a variable that becomes 1 when the j−1th product type i is produced and 0 otherwise. is there. Then, the production order is determined by a method of producing a product i giving the maximum value of _Xij .

For example, two a engines per day from vehicle assembly factory A, one b engine per day from vehicle assembly factory B,
At the engine assembly factory where one c engine per day was requested from the vehicle assembly factory C, a, b, c
The engine production order was decided. That is, the production ratio of engine a is 2 / (2 + 1 + 1) = 0.5, and
The engine production ratio is 0.25, and the engine production ratio is 0.
Since it is 25, X _a1 = 0.5, X _b1 = 0.25, and X _c1 = 0.25.
Among them, the largest is X _a1 , so the first makes an a engine. Next, X _a2 , X _b2 , and X _c2 are obtained.

X _a2 = X _a1 + 0.5-1 = 0 X _b2 = X _b1 + 0.25-0 = 0.5 X _c2 = X _c1 + 0.25-0 = 0.5 Since the maximum is X _b2 or X _c2 , for example, X The second builds a b engine, with _b2 as the maximum. Similarly, X _a3 = X _a2 + 0.5-1 = 0.5 X _b3 = X _b2 + 0.25-1 = 0.25 X _c3 = X _c2 + 0.25-0 = 0.75 Of these, the largest is X _c3 , Third, build a c-engine. Similarly, X _a4 = X _a3 + 0.5-0 = 1 X _b4 = X _b3 + 0.25-0 = 0 X _c4 = X _c3 + 0.25-1 = 0 Of these, the largest is X _a4, so The fourth builds an a engine. That is, the production order of four engines per day is a, b, c, a.

Subsequently, on the second day, X _a5 = X _a4 + 0.5-1 = 0.5 X _b5 = X _b4 + 0.25-0 = 0.25 X _c5 = X _c4 + 0.25-0 = 0.25, which is X _a1 , X _b1 , and X _c1 , so that the second day is prepared in the same order as a, b, c, and a as in the first day.

The reason for the above calculation is that P _i is obtained for the first day, and can be used on the second day,..., N day without changing P _i .

[Problems to be solved by the invention]

However, in the conventional production sequence planning method, the input information is given in the form of a production line in which the input information is given in the form of the daily production volume of each product (necessary date, what kind of product and how many products need to be produced). Is effective because the production ratio P _i is determined in the above formula, but the input information of the production sequence plan is not effective, such as a complete knockdown line (a packing line for packing parts in Japan and sending them overseas). In a production line given in the form of a designated production period (in the case of a packing line, a designated packaging period, that is, between what day and how many products must be packed in what boxes), since in can not be calculated for P _i, conventional production sequence method was not applicable.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a production sequence planning method that is effective even when production input information is given in the form of a production designation period for each product type in a production line for many types of products.

[Means for solving the problem]

According to the present invention, the above object is achieved by the following production sequence planning method. That is, input production information given in the form of a production designation period for each product type and the number of product productions within the production designation period, and divide the number of product productions for each product type by the number of days of the production designation period for each product type. Calculate the expected production value for each designated period consisting of the daily production number, calculate the total production number per day by adding the production expectation value for all product types for each day, apply integer processing to the total production number per day, A vacant seat for the production after the integer conversion is provided for the day, a serial number j is assigned to the vacant seat, and a production expected value column for writing the expected production value X _ij of the product type i is provided for each vacant seat. X _ij is obtained by the following equation. X _i1 = P _i1 X _ij = X _ij-1 + P _ij −δ _ij-1 where X _ij : product type i, expected production value in order j, P _ij : product type i, Product type i of expected production value for each specified period on the production date including order j Sum of about, [delta] _ij: sequence when produced product type i j
Is the sum of the daily production expected values for the specified period on the production date including all product types, the variable which becomes 0 in other cases, the order j corresponding to the obtained production expected value X _ij and the product type i Into the expected production value column of the production order, and the expected production value X for the order j
The production order among the product types is determined by the leveling process for keeping the product interval constant, which means that the product type with the largest expected production value of _ij is determined as the product type to be produced in the vacant seat of order j. Determining a production sequence planning method.

[Action]

By summing the expected production value for each specified period for each day and performing integer processing, how many units should be produced for each day,
That is, since the expected daily production value (corresponding to the conventional daily production number) is obtained, the production sequence plan can be implemented. However, while changing the production ratio P _ij for each day (conventionally P
_i is constant) leveling must be performed.

〔Example〕

Hereinafter, a preferred embodiment of the production sequence planning method according to the present invention will be described with reference to the drawings.

FIG. 1 shows an overall configuration in the case where the present invention is applied to a production line including, for example, a complete knockdown parts packing line, and FIGS. 2 and 3 show the specific contents thereof.

In FIG. 1, information to be input according to the present invention is externally provided by an operator's hand, a communication line, or the like, and stored in a production plan input file 1-1.

As shown in FIG. 2, the input information is in the form of a packing designation period for each product type (a production designation period, but since the production line uses a packing line as an example, it is a packing designation period. The same applies hereinafter). Given. For example, product A
Indicates that it is necessary to pack one box every one to two days, one box every one to four days, and one box every four to five days for each post-process (for example, for the United States). Further, for a product B in another post-process (for example, for Europe), it is necessary to pack one box every 1 to 5 days.

Based on the input file information, the system first calculates the expected packing value for each designated period in step 1-2 in FIG.
calculate. The expected value of packing for each designated period is obtained by dividing the number of packages for each product type by the number of days for the designated packing period to calculate the number of packages per day for each product type.

For example, as shown in FIG.
One box for 1-2 days is distributed in 0.5 boxes a day, 0.5 boxes for 2 days, 1 box for 1-4 days is 0.25 boxes for 2 days, 0.25 boxes for 2 days, 3 boxes for 3 days
0.25 boxes per day, 0.25 boxes on 4 days, 0.5 boxes on 5 days
One box for 4-5 days is distributed to 0.5 boxes for 4 days and 0.5 boxes for 5 days. Similarly, the products B and C are subjected to the same equal distribution processing.

Next, in step 1-3 in FIG. 1, the expected value of packing for each designated period consisting of the number of packages per day described above is added up for all the product types, and as shown in FIG.
2. Calculate 1.45, 0.95, 1.45, 0.95. Subsequently, the total number of packages per day is converted into an integer.

The procedure of the integer ratio is performed by selecting an integer closest to a value obtained by adding the residual for the current day. For example, 1.2 of the day is 2
Therefore, one box is used for one day, and a residual of 0.2 is carried over to the next day. On the second day, 1.45 for the current day and the previous day's residual 0.2 were added to give 1.65. Since 1.65 is closer to 2 than 1, it is 2
The day is two boxes, and the residual -0.35 is passed to the next day. Three days,
Add 0.95 for the current day and the residual -0.35 of the previous day to 0.6, which is closer to 1 than 0, so it is 1 box for 3 days, and the residual -0.4
Will be carried over to the next day. On the 4th, 1.45 for the day and the previous day's residual-
Add 0.4 to 1.05, which is closer to 1 than 2 so
One box is taken on the fourth day, and a residual of 0.05 is carried over to the next day. Similarly,
On the 5th, add 0.95 for the day and 0.05 for the previous day and add 1.00 to make 1.00. Thus, the total number of packages after integer conversion, 1,
2,1,1,1 are obtained.

Next, in step 1-4 in FIG. 1, leveling processing (processing for keeping product production intervals constant) is performed, and based on the result, in step 1-5 in FIG. Determine the production order between product types.

FIG. 5 shows the leveling process and the procedure for determining the production order. First, vacant seats are provided for each day by the number of packages after the conversion into integers, and serial numbers are assigned to them. For example, on the first day, one vacant seat is provided because the number of integral packages is one, and on the second day, two vacant seats are provided because the number of packages after integral is two.
One vacant seat is provided for each of the fifth and fifth days, and serial numbers 1, 2, 3, 4, 5, and 6 are assigned to them, as shown in FIG. Therefore, serial number 1 indicates the order of products packed on the first day, serial numbers 2 and 3 indicate the order of products packed on the second day, and serial number 4 indicates products packed on the third day. The serial number 5 indicates the order of products packed on the fourth day, and the serial number 6 indicates the order of products packed on the fifth day. Below the serial numbers, columns for writing expected packing values of the product types A, B, and C are provided. For example, 0.75 below the serial number 1, 0.
2, 0.25 indicates the expected packing value of the product type.

In FIG. 5, the expected production value is obtained as follows.

X _i1 = P _i1 X _ij = X _ij-1 + P _ij −δ _ij-1 where X _ij is an expected production value in product type i and order j, and P _ij includes product type i and order j. Δ _ij is the sum of the expected productive value for each specified period on the production date including the order j when the product type i is produced. This is a variable that is the sum total per day, which is the sum of

For example, as shown in FIG. 5, the production expected sequence j is the first value X _A1, X _B1, X _{C1 is, P A1, P B1, P} C1 becomes, in Figure 3, P _A1 product type A Is calculated as the sum of the expected values 0.5 and 0.25 for the product type B, that is, 0.75, P _B1 is obtained as the expected value 0.2 for the product type B on the first day, and P _C1 is the expected value 0.25 for the product type C on the first day. Is required. In this case, since the largest expected packing value of 0.75, 0.2, and 0.25 is 0.75 of i = A, it is determined that the product type A is packed first in the order j = 1.

For j = second, X _A2 = X _A1 + 0.75 + 1.2 = 0.3 X _B2 = X _B1 + 0.2-0 = 0.4 X _C2 = X _C1 + 0.5-0 = 0.75. Then, 0.75 of these, the most Oki prayer is X _C2
Therefore, j = 2 is determined to pack the product type C. In the above, 0.75 of the expression of X _A2 is the sum of the expected values of 0.5 and 0.25 on the second day in FIG.
Because I was packing, and the first day of the day the total number 1.2 of FIG. 4 X _A2
This shows that only the expression Similarly, where the X _B2, 0.2 the second day of the third diagram, the expectation value 0.2 of B, X _C2
In the equation, 0.5 is the expected value of C on the second day in FIG.
Is the sum of In the expressions of X _B2 and X _C2 , 0 indicates that δ _ij is 0.

Similarly, for j = third, X _A3 = X _A2 + 0.75-0 = 1.05 X _B3 = X _B2 + 0.2-0 = 0.6 X _C3 = X _C2 + 0.5-0.45 = -0.2 X _A3 So j = 3-th of the largest value is the product type A is packed.

Similarly, for j = 4th, X _A4 = X _A3 + 0.25-1.45 = -0.15 X _B4 = X _B3 + 0.2-0 = 0.8 X _C4 = X _C3 + 0.5-0 = 0.3, and j In the fourth case, the product type B is packed.

Similarly, for j = fifth, X _A5 = X _A4 + 0.75-0 = 0.6 X _B5 = X _B4 + 0.2-0.95 = 0.05 X _C5 = X _C4 + 0.5-0 = 0.8, and j = Fifth, the product type C is packed.

Similarly, for j = 6th, X _A6 = X _A5 + 0.5-0 = 1.1 X _B6 = X _B5 + 0.2-0 = 0.25 X _C6 = X _C5 + 0.25-1.45 = −0.4, and j In the sixth case, the product type A is packed.

That is, on the first day (j = 1) A is packed, on the second day (j = 2, 3) C and A are packed in that order, and on the third day (j = 4) B Is packed, and the fourth day (j = 5) is C
Are packed, and on the fifth day (j = 6), A is packed, and so on. The procedure of determining the packing order and keeping the packing interval constant in this way is called leveling.

In determining the packing order by this leveling process, P _ij
Is calculated as the sum of the expected value for each specified period of the production day including the order j for the product type i, and can be calculated. In addition, since P _ij changes at any time along the order j,
P _i as in the prior art as compared with the case was constant regardless of the j, different.

〔The invention's effect〕

According to the production sequence determination method of the present invention, even if the production plan input information is given in the form of a production period, the number of productions in the production period is divided by the number of production period days to calculate the expected production value for each designated period, and The production numbers per day are obtained by summing them up for each day and converting them into integers, and by performing leveling processing based on these to determine the order, the production order of the product type can be determined.

By determining the production order according to the present invention, the following conflicting productions are possible: (a) adherence to delivery date (products are produced within a designated period); (b) leveling (making the production intervals of products constant). A production order of products that satisfies the conditions is obtained.

In this case, by satisfying the above condition (a),
The product inventory of the own process can be greatly reduced, and the line stop in the post-process due to product shortage can be significantly reduced.

By satisfying the condition (b), the stock of parts in the previous process can be greatly reduced, and the line stoppage of the own process due to missing parts can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a system for carrying out the present invention, FIG. 2 is an input information diagram showing an example of production input information given to the production plan input file of FIG. 1, and FIG. 3 is an input of FIG. An expected value diagram showing an example of the expected production value for each designated period obtained from the above. FIG. 4 shows the total daily production and the integer value of the total count obtained from the expected production value for each designated period in FIG. FIG. 5 is a leveling process based on the data of FIGS. 3 and 4 and a leveling process and a production order determination diagram showing the production order determined by the data. is there. 1-1: Production plan input file process 1-2: Expected production value calculation process by specified period 1-3: Total production number per day process 1-4: Leveling process 1-5 … Production sequence output file process

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) B23Q 41/08 B23P 21/00 307 B62D 65/00

Claims (1)

(57) [Claims] Claims: 1. Input production information given in the form of a designated production period for each product type and the number of product productions within the designated production period, and divide the number of product productions for each product type by the number of production designated period days. Calculate the expected production value for each specified period consisting of the daily production number of the product type, calculate the total production number per day by adding the expected production value for each product type for each day, and convert the total production number per day to an integer. Vacant seats for the production after integer conversion are provided for each day, a serial number j is assigned to the vacant seats, and a production expectation value column for writing the expected production value X _ij of the product type i is provided for each vacant seat. Production expected value X
_ij is obtained by the following equation, and X _i1 = P _i1 X _ij = X _ij-1 + P _ij −δ _ij-1 where X _ij : product type i, expected production value in order j, P _ij : product type i, order sum of the expected production value for each specified period on the production date including j for the product type i, δ _ij : if the product type i is produced, all products of the expected production value for each specified period on the production date including order j Grand total per day, sum of types, 0 otherwise
The expected production value X _ij obtained is written in the expected production value column of the corresponding order j and product type i, and the expected production value X for the order j is written.
The production order among the product types is determined by the leveling process for keeping the product interval constant, which means that the product type with the largest expected production value of _ij is determined as the product type to be produced in the vacant seat of order j. Determining a production sequence planning method.