JPH10149205A - Unit and method for lot control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the total in-process of a flowing lot in a line and to maximize the facility operation rate by determining the number of lots in-process from process permissible processes per unit time by quality and determining the concrete process procedure of lots in process of process permissible processes within quality. SOLUTION: A determining means 1 for the number of starting lots by kinds reads data out of line data 4 and determines the number of starting lots per unit time by kinds as for respective kinds of waiting lots in buffer process by making good use of a linear programming method, etc., so that the facility operation rate becomes maximum without exceeding the process capability of neck facilities. An in-quality starting procedure determining means 2 reads in-process data 42 out and determines the starting order of waiting lots by all the kinds of waiting lots in buffer process. A starting indication means 3 indicates intervals and the starting order of lot starting from the buffer process to a next process as to all the kinds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lot control apparatus and a lot control method, and more particularly, to a case where equipment such as a semiconductor manufacturing line has a high load because one equipment is used in a plurality of processes. The present invention relates to a lot control device and a lot control method used when there is a loop process that repeats a similar process procedure.

[0002]

2. Description of the Related Art Conventionally, a lot control apparatus and a lot control method of this kind are used for controlling a processing order so as to give priority to a work of a lot whose delivery time is imminent in consideration of a lot delivery time. Have been. A conventional lot control device is disclosed, for example, in Japanese Patent Application Laid-Open No. 5-143116.

[0003] The production control system disclosed in this publication includes a plurality of pallets on which workpieces are placed, a plurality of manufacturing facilities, a transport device for delivering the pallets to any facilities, and an automatic warehouse capable of taking out any workpieces. A work priority determining mechanism and a work request right issuing mechanism, wherein the work request right issuing mechanism grants the work request right in order from the work having the highest priority, and the pallet receiving the work request right has a plurality of pallets. It negotiates with the equipment to determine and proceed to the next work on the work on the pallet.

According to the conventional production control system, the work request right issuing mechanism controls the order of work requests,
Work can be performed in consideration of the delivery date.

[0005]

A conventional production control system is based on a work plan established in advance and the actual progress of a lot, and the processing order is determined by giving priority to the one with a small margin for the delivery date. It is.

However, irrespective of the status of the production line, a lot is input to and controlled on the production line in accordance with a preset input plan. If the equipment load or work-in-progress changes due to equipment trouble, etc., or if the plan evaluation index (delivery time compliance rate, equipment operation rate, work-in-process amount, etc.) is changed on the way, the plan evaluation index and actual There is a problem that the possibility of a large difference is great.

Further, since the lot arrival procedure is determined in consideration of the delivery date from among the lots to be started, there is a problem that the optimal lot processing timing cannot be set in accordance with the change of the line condition. Was.

The present invention has been made in view of the above problems, and in a manufacturing line in which the equipment state and the work-in-process change, the overall work-in of a lot flowing through the line is reduced.
An object of the present invention is to provide a lot control device and a lot control method capable of maximizing a facility operation rate.

[0009]

SUMMARY OF THE INVENTION A lot control apparatus according to the present invention determines the number of start lots per unit time for each type with respect to the start of a lot from a process permitting process on a production line. Means, type internal arrival procedure determining means for determining the lot arrival procedure for each type of product in the in-process permissible process, and lot start content determined by the type-specific start lot number determining means and type internal arrival procedure determining means Start instruction means for instructing start according to the following.

[0010] The lot control device of the present invention may further include a start instruction review detecting means for judging whether the lot start instruction needs to be reviewed at predetermined time intervals.

The number-of-starting-lots determining means for each kind is based on the line data on the production line, and the equipment for each kind of the lot waiting to be started in the in-process allowable process is provided within the processing capacity of each equipment. The number of starting lots per unit time for each product type is determined so that the operation rate is maximized.

The type-specific starting lot number determining means may determine the ratio of the starting lot number of each type in accordance with the priority between the types, and the process procedure with the in-process allowable process at the top is grouped. Alternatively, the number of starting lots per unit time may be determined for each product type and each group in the process-permissible process.

According to the lot control method of the present invention, (1) the number of lots to be started per unit time for each product type is determined for the start of lots from the in-process allowable process of the production line;
A lot arrival procedure is determined for each product type in the in-process permissible process, and (3) a start instruction is issued based on the determined number of start lots and the lot arrival procedure.

[0014] The lot control method of the present invention may further include a step of determining whether or not the lot start instruction needs to be reviewed at predetermined time intervals.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of the first exemplary embodiment of the present invention. First of the present invention
In the embodiment, as shown in FIG. 1, a lot is temporarily stopped in a line data 4 relating to a production line and a step of permitting a stagnation of one or more processes in progress in a production procedure (hereinafter referred to as a buffer step). Starting instruction means 3 for instructing the start of a lot from the buffering process to the next process; and starting lots for each type for determining the number of starting lots per unit time from the buffering process for each type of product having different manufacturing procedures or manufacturing conditions. In accordance with the number of starting lots per unit time determined by the number determining means 1 and the type-specific starting lot number determining means 1,
It is composed of a lot to be started in the next unit time for each product type from a plurality of lots in the buffer process, and a product internal arrival procedure determining means 2 for determining the product arrival procedure.

The line data 4 comprises a product type master 41 and in-process data 42. The type master 41 stores reference information such as a manufacturing procedure, equipment used, and a standard processing time for the type flowing through the manufacturing line. The product type master 41
For example, as shown in FIG.
12 and its process 413, equipment 414 used for each process,
The work time 415 for each lot in each process is stored. The in-process data 42 is totaled from the tracking information of the production line, and stores information on the in-process lot 422 for each type 421 in the buffer process, for example, as shown in FIG.

FIG. 2 is a flowchart for explaining the operation of the first embodiment of the present invention. First, the type-specific starting lot number determining means 1 reads data stored in the type master 41 and the in-process data 42 (step S).
1).

Next, using a linear programming method or the like, the equipment operation rate is maximized for each type of the lot waiting to be started in the buffer process, within a range not exceeding the processing capacity of the neck equipment. Next, the number of starting lots per unit time for each type is determined (step S2).

Next, the kind internal arrival procedure determining means 2 reads the in-process data 42 and determines the arrival procedure of the start waiting lot for each kind for all the kinds of the waiting lots in the buffer process (step). S3, S4).

Next, the start instructing means 3 instructs, for all the products, the interval and the procedure for starting the lot from the buffer step to the next step (step S5).

According to the present invention, the number of starting lots per unit time for each type of product in the buffer process is determined so that the equipment operation rate is maximized within a range not exceeding the processing capacity of all the equipment used. Therefore, there is no more work in process than necessary in the production line, and the equipment operation rate can be maximized. This is because if the leading step of the process procedure is a buffer step in each product type, lots exceeding the processable amount will not be put into the production line.

FIG. 5 is a diagram showing a type master according to a modification of the first embodiment. As shown in FIG. 5, the type-specific starting lot number determining means 1 regards the process procedure for each type as a group 416 with the buffer process at the top (hereinafter, referred to as a group 416).
The number of starting lots per unit time is determined for each type of product in the buffer process and for each group.

In the modification of the first embodiment, the type-specific starting lot number determining means 1 determines the number of starting lots per unit time for each type and for each group. There is a similar set of procedures in the process procedure, and the same equipment is used multiple times in all the process procedures. be able to.

Next, the operation of the first embodiment of the present invention will be described in more detail. FIG. 3 which is an example of the product type master 41
Referring to, the process procedure of the product type A is a process a, a process b,
Steps c, d,... Are lined up, and the equipment used in each step is equipment 1, equipment 2, equipment 3, equipment 4.
... and work time per lot m _A1 , m _A2 , m
It can be seen that _A3 , _mA4 ... In the type A, type B, and type C mixed and flowing on the same manufacturing line, the buffer step is a which is the first step of each step, and the start instruction means 3 sets the start interval of the lot from the step a. And the arrival procedure of the lot. Further, referring to FIG. 4 which is an example of the in-process data 42, it is possible to know the lot in process for each type in the process a which is the buffer process.

The first kind-specific starting lot number determining means 1 includes:
For example, the number of starting lots per unit time is determined for each type of product in the buffer process so that the equipment operation rate is maximized within a range not exceeding the processing capacity of each equipment. As an example of the conditional expression of the linear programming method, the unit time is set to one hour, and the number of starting lots of each type per unit time is determined based on the condition that the load on each facility does not exceed the processing capacity of the facility. Assuming that the number of starting lots of each type per unit time to be obtained is X _A , X _B , X _C ..., The working time per lot is m _ik (i = types A, B, C,...)
·, K = equipment 1, 2, 3, ...), so for each equipment,

[0026]

(Equation 1) Can be created. Also, based on the assumption that the capacity utilization rate will be maximum,

[0027]

(Equation 2) Can be created. By solving these equations 1 and 2, the starting lot numbers X _A , X _B , X _C ... Of each kind can be obtained.

Further, when there is a difference in the priority between the types, the ratio of the starting lot number of each type can be changed according to the priority. For example, type A, type B, type C
(Assuming that the higher the priority is, the larger the value of the priority is) P _A , P _B , and P _C , the number of starting lots of each type is calculated in addition to Expressions 1 and 2,

[0029]

(Equation 3) Is added. In the case where the flow in level and not the priority of the difference between varieties, can be thought of as all the values of P _i 1, the number undertaken lots of all kinds becomes equal.

The in-kind arrival procedure determining means 2 reads the in-process data 42, and arranges the in-kind lot arrival procedure for each kind, for example, in the order of shorter time to delivery, in the order of longer stagnation time, in the order of priority, and the like. Is determined by applying the rules described above.

The number-of-starting-lots determining unit 1 according to the modification of the first embodiment determines the number of starting lots per unit time for each type of group in the buffer process. As an example of the conditional expression of the linear programming, the unit time is set to one hour, and the number of starting lots of each type and each group per unit time to be obtained is X _1A , X _2A , X _1B ...
Then, since the work time per lot is _mik ,

[0032]

(Equation 4)

[0033]

(Equation 5) Can be created. By solving Equations 4 and 5, the starting lot numbers X _1A , X _2A , and X _{1B of} each type and each group are obtained.
... can be obtained. Note that since all groups do not always have all groups, _Xji of the type i in which the group j does not exist is set to 0.

Next, a second embodiment of the present invention will be described in detail with reference to the drawings. FIG. 6 is a block diagram showing a configuration of the second exemplary embodiment of the present invention. In the second embodiment of the present invention, as shown in FIG. 6, a start instruction review detecting means 5 is added to the first embodiment shown in FIG.

The start instruction review detecting means 5 evaluates whether it is necessary to review the already specified lot start instruction for each product type and group with reference to the line data 4 at predetermined time intervals. Then, when it is necessary to review, the instruction to re-calculate the contents of the start instruction is given to the type-specific start lot number determining means 1.

FIG. 7 is a flowchart for explaining the operation of the second embodiment of the present invention. The operations of the type-specific start lot number deciding means 1, the type-internal arranging procedure deciding means 2 and the start instructing means 3 in the second embodiment shown in steps S1 to S5 of FIG. 7 are the same as those of the first embodiment. Operation is the same.

In the second embodiment, after the start instructing means 3 issues a start instruction to the in-process lot waiting to be started in the buffering process, the start instruction reviewing detecting means 5 sets the line data 4 at regular time intervals. Is read, and it is determined whether it is necessary to review the contents of the start instruction given in step S5 (step S6). If it is necessary to review the contents of the start instruction, the type-specific start lot number determining means 1 is notified of the recalculation of the number of start lots for each type of group, and the same step S1 as the operation of the first embodiment is performed. From step S5.

In the second embodiment, for example, when the number of in-process lots of a product type or a group fluctuates beyond a certain value, a value (referred to as a marginal change rate) for revising the starting lot number is predetermined. The start instruction review detecting means 5 reads the number of in-process lots in the buffer process for each product type group from the in-process data 42, and if the number of in-process lots increases or decreases beyond the marginal change rate, When the balance is greatly changed, it is determined that the start instruction needs to be reviewed.

In the second embodiment, the start instruction review detecting means 5 determines at a predetermined time interval whether the start instruction needs to be reviewed. For this reason, a proper lot start instruction can always be given even for a production line in which the state of the work-in-process is likely to fluctuate.

The present invention is not limited to the above-described embodiment, and various changes can be made within the technical scope described in the claims.

[0041]

According to the present invention, the in-process permissible per unit time for each type is determined based on the in-process status of the lot in the in-process permissible process of the production line and the master information on the type in the production line. Determine the number of starting lots from the process,
After that, since the specific arrival procedure of the in-process lot of the in-process allowable process within the product type is determined, the overall in-process lot of the lot flowing through the production line is reduced even in the production line where the equipment status and the in-process change. In addition, the facility operation rate can be maximized, and the productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the first exemplary embodiment of the present invention.

FIG. 3 is a diagram showing an example of a product type master of FIG. 1;

FIG. 4 is a diagram illustrating an example of in-process data of FIG. 1;

FIG. 5 is a diagram illustrating a type master according to a modification of the first embodiment;

FIG. 6 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 7 is a flowchart for explaining the operation of the second exemplary embodiment of the present invention.

[Explanation of symbols]

 1: Type-specific start lot number determining means 2: Type internal arrival procedure determining means 3: Starting instruction means 4: Line data 41: Type master 42: In-process data 5: Starting instruction review detecting means

Claims (7)

[Claims] 1. A type-specific start lot number determining means for determining the number of start lots per unit time for each type with respect to the start of a lot from a process allowance step of a production line; A kind internal arrival procedure determining means for determining a lot start procedure for each kind, and a start instruction means for giving a start instruction in accordance with the lot start content determined by the kind-specific start lot number determining means and the kind internal arrival procedure determining means, A lot control device comprising: 2. The lot control device according to claim 1, further comprising a start instruction review detecting means for determining whether or not the review of the lot start instruction is necessary at predetermined time intervals. 3. The type-specific start lot number determination means, for each type of a start-waiting lot set in a process-permissible process, based on line data on a production line.
3. The lot control device according to claim 1, wherein the number of starting lots per unit time for each type is determined so that the facility operation rate is maximized within a range not exceeding the processing capacity of each facility. 4. 4. A method according to claim 1, wherein said type-specific starting lot number determining means determines the ratio of the starting lot number of each type according to the priority between the types. Item lot control device. 5. The type-specific start lot number determining means groups the process procedures with the in-process allowable process at the top, and sets the number of start lots per unit time for each type of product in the in-process allowable process. The lot control device according to any one of claims 1 to 4, wherein 6. The method according to claim 1, wherein: (1) determining the number of lots to be started from the in-process allowable process of the production line per unit time for each type of product; and (2) determining the type of product in the in-process allowable process. A lot control method comprising: determining a lot arrival procedure for each lot; and (3) giving a start instruction based on the determined number of start lots and the lot arrival procedure. 7. The lot control method according to claim 6, further comprising the step of judging at a predetermined time interval whether it is necessary to review the contents of the lot start instruction.