JP4244553B2 - Production management apparatus and product production method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a production management apparatus and a product production method, and more particularly to a technique for managing products flowing through a relatively complicated production line such as branching or merging.
[0002]
[Prior art]
Conventionally, in a vehicle production instruction system or the like, management is generally performed in units of rough processes such as body, painting, and assembly, and there is a need to manage each process in detail. On the other hand, in order to grasp the production progress of a product, there is a technology for finally predicting the scheduled completion date of a product by obtaining the processing start / end time at each facility of each product at a production site as in Japanese Patent No. 2721561. Are known. In this technology, based on the latest product progress information at the time of forecast and information including the setup status of each equipment, the current setup at each equipment and the delivery date of the products waiting to be processed in front of each equipment. In consideration of this, products to be preferentially started are determined, and the start order for each facility is predicted and output to a CRT or the like.
[0003]
[Problems to be solved by the invention]
However, the above-mentioned conventional technology basically targets products that flow from the upstream to the downstream of the production line. For example, the flow simply flows from the upstream to the downstream, such as multiple coatings in the vehicle painting process. In addition, there are complicated processes such as branching to another process after a certain process is completed, and joining the original production line again after passing through a predetermined process. In the prior art, it is difficult to cope with such a complicated production line involving branching and merging, and there is a problem that the progress of each product cannot be accurately managed.
[0004]
The present invention has been made in view of the above-described problems of the prior art, and its purpose is to make the product more detailed and accurate even when a product is produced on a relatively complicated production line involving branching and merging. It is to provide an apparatus and a method capable of producing a product.
[0005]
[Means for Solving the Problems]
To achieve the above object, the present invention relates to the relationship between the tracking points for each product and the tracking points and the process elements when the production line is modeled with process elements and tracking points connecting the process elements to each other. And means for controlling the production line based on the relationship between the tracking points and the relationship between the tracking points and the process elements, and the means for storing comprises: Without memorizing the relationship during abnormal processing The relationship at the time of normal processing is stored, and the means for controlling determines whether or not the product can pass the tracking point based on the relationship. In the case where the tracking point to which the product is going to pass is present on the downstream side of the production line with respect to the tracking point that has passed immediately before, it is determined whether or not the product can pass using the relationship stored in the storing means. Shi In the case where the tracking point through which the product is going to pass is located on the upstream side of the production line with respect to the tracking point passed immediately before Stored in the storing means The passage of the product is permitted regardless of the relationship.
[0006]
Here, when the number of times the tracking point through which the product attempts to pass is limited, the control means preferably determines whether or not the product can pass based on the number of times.
[0007]
Further, the present invention models a production line with process elements and tracking points connecting the process elements to each other, and the relationship between the tracking points for each product and the relationship between the tracking points and the process elements are stored in a computer memory. And storing the product on the production line by outputting an instruction from the computer to an output device provided at a predetermined position on the production line based on the relationship between the tracking points and the relationship between the tracking points and the process elements. Process sequentially with By computer A product production method, wherein the memory is as the relationship Without memorizing the relationship during abnormal processing The relationship at the time of normal processing is stored, and the computer determines whether the product can pass the tracking point based on the relationship, and outputs the instruction. When the tracking point to which the product is about to pass is present on the downstream side of the production line with respect to the tracking point that has passed immediately before, the use of the relationship stored in the memory is used to determine whether or not the product can pass. When the tracking point to which the product is about to pass is located upstream of the tracking point that has passed immediately before the production line Stored in the memory An instruction is output to permit passage of the product regardless of the relationship.
[0008]
Also in this method, when the number of passages of the tracking point through which the product is to be passed is limited, it is preferable that the computer determines whether the passage is possible or not and outputs the result.
[0009]
Tracking points are logical passing points that connect processes. For example, even if there are branches in the production line, a branch production line can be expressed by setting a tracking point for each branch. . In addition, for a merge, a merge production line can be easily expressed by setting a tracking point for each merge channel. When the process after the branching is changed, the process element connected to the tracking point may be changed, and the model can be easily handled corresponding to the change of the production line.
[0010]
However, if the relationship is defined not only for normal processing but also for abnormal processing such as a rework process, the number of relationships to be defined becomes enormous and leakage is likely to occur. Therefore, as in the present invention, normal processing and abnormal processing are separated, and the relationship regarding normal processing is stored. The reworking process shall be processed separately, and considering the case where the reworked product has returned to the production process, the tracking point to which the product is going to pass is more If the product exists on the upstream side, it is possible to easily deal with a reworked product by permitting the passage of the product regardless of the relationship.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
First, the prerequisite technology of this embodiment will be described. FIG. 1 shows an example of a production line managed in the present embodiment. The production line shown in the figure shows the painting process of the vehicle. First, the intermediate coating step a exists, and the intermediate coating step b exists after the intermediate coating step a. The vehicle that has completed the overcoating step b then enters the overcoating inspection step c to inspect whether the overcoating has been performed according to a predetermined standard. After the top coating inspection process c is completed, the process proceeds to a final coating inspection process f depending on the vehicle, and after the final coating inspection process f is completed, the process proceeds to a next stage process, for example, an assembly process. On the other hand, depending on the type of vehicle, after the top coating inspection process c is completed, the multi-color coating returning process d may be entered and painting may be performed again. The vehicles that have completed the multi-time coating return process d join the original production line again and enter the top coating process b again. The vehicle that has completed the top coating step b enters the top coating inspection step c. If the inspection result is OK, the vehicle proceeds to the final coating inspection step f, where the final inspection is performed. For a vehicle that has been determined to be NG in the top coating inspection process c, the process proceeds to the top coating reworking process e and proceeds to the next process without proceeding to the final coating inspection process f or the multiple coating return process d.
[0013]
Thus, the coating process in the present embodiment is a process that branches from the top coating inspection process c to the final coating inspection process f or the multiple coating return process d and a process that joins the multiple production return process d to the original production line. It is necessary to accurately grasp which process should be proceeded to for each vehicle and whether or not the process in each process is performed as scheduled.
[0014]
Therefore, in the present embodiment, the production line shown in the figure is modeled, and the computer collectively manages and outputs an instruction to each process of the production line based on the modeled production line. The production line in the present embodiment is modeled as a tracking point that connects between process elements. The process element corresponds to each process such as the intermediate coating process a, the top coating process b, and the top coating inspection process c described above, and the tracking point corresponds to a passing point when moving from a certain process to the next process. A passing point is a physically existing point, but a tracking point is a logically existing point. For example, at a branch point in a production line, a plurality of tracking points are set for each branch path. For example, in FIG. 1, there are a final coating inspection step f, a multiple-time coating return step d, and a top coating reworking step e as the steps that the vehicle should proceed from the top coating inspection step c. Three tracking points E, F, and G are also set. Similarly, at the junction point in the production line, there are a route entering from the intermediate coating step a to the top coating step b and a route entering the top coating step b from the multiple coating return step d, corresponding to these two routes. Thus, two logical tracking points A and B are set.
[0015]
FIG. 2 shows basic rules for setting tracking points. Process elements and process elements are not directly connected, but are always connected via tracking points. That is, process element-tracking point-process element. On the other hand, as shown in (a), a plurality of process elements 11 can be connected in front of one tracking point 100. Such an aspect corresponds to, for example, a meeting point of a production line. Further, as shown in (b), a plurality of tracking points 100 can be connected after a certain process element 11, and after each tracking point 100, the process element 11 is connected as already described. This corresponds to a branch point in the production line, for example. On the other hand, as shown in (c), a plurality of process elements 11 cannot be connected after a certain tracking point 100. This is because, if a plurality of process elements are connected to one tracking point, it is not possible to uniquely define which process should proceed next. Under such basic rules, a production line is modeled using process elements and tracking points, and a production process of a product traveling on the production line is expressed using these process elements and tracking points.
[0016]
3 and 4 show examples of tables when a production process is expressed using tracking points and process elements. FIG. 3 is a table that defines the relationship between process elements and tracking points, and FIG. 4 is a table that defines the relationship between tracking points.
[0017]
First, in FIG. 3, for each tracking point set on the production line, a process element existing after the tracking point is related. For example, in the example of FIG. 1, the overcoating step b exists after the tracking point A, and the overcoating inspection step c exists after the tracking point C. Therefore, the relationship between the tracking point and the process element is
Tracking point A-process element b
Tracking point C-process element c
And so on. At the branch point, the process existing after the tracking point E is a multi-time coating return process d, the process existing after the tracking point F is the final coating inspection process f, and the process existing after the tracking point G. Is the overcoating process e.
Tracking point E-process element d
Tracking point F-process element f
Tracking point G-process element e
Can be related. In this way, by associating a certain tracking point with a process element existing thereafter, it is possible to determine which process a vehicle that has passed a certain tracking point should proceed next by referring to this table. Or, conversely, it is also possible to uniquely determine which tracking point the vehicle that has progressed through a certain process has passed in the past.
[0018]
On the other hand, in FIG. 4, the relationship between tracking points is defined as described above. For example, for a vehicle in FIG.
Intermediate coating process a-Tracking point A-Top coating process b-Tracking point C-Top coating inspection process c-Tracking point F-Final coating inspection process f-Tracking point H
However, in another vehicle, it branches to the multi-color coating return process d from the middle,
Intermediate coating process a-Tracking point A-Top coating process b-Tracking point C-Top coating inspection process c-Tracking point E-Multiple coating return process d-Tracking point B-Top coating process b-Tracking point D-Top coating inspection process c- The process proceeds to the next stage through a process of tracking point F-painting final inspection process f-tracking point H. Focusing on the relationship between the tracking points in these processes, a certain vehicle passes the tracking point A before the tracking point C and passes the tracking point C before the tracking point E. Since it passes through the tracking point E before B, the tracking path (passage point) and the tracking point that should pass in front of it are specified in order, That is, the production process can be uniquely determined. When different production processes are performed for each vehicle, this relationship is defined for each vehicle (for each vehicle type). Then, by referring to this table when a vehicle passes a certain tracking point, it is determined which tracking point the vehicle has passed in the past or which tracking point should be passed next. It becomes possible to do. Of course, by referring to both the relationship shown in FIG. 3 and the relationship shown in FIG. 4, a vehicle that has passed a certain tracking point should go through which process, and then go through which tracking point. You can decide at the same time what to do.
[0019]
In FIG. 4, there is a main / sub classification, but the main is basically a tracking point through which the vehicle always passes, and the sub does not normally pass but passes when there is an abnormality (when a quality defect occurs). Indicates possible tracking points. In the example of FIG. 1, the tracking points A, B, C, D, E, F, and H are main, and the tracking point G is a sub. This is because the tracking point G is a tracking point that passes when the abnormality is detected in the overcoating inspection step c and the process proceeds to the overcoating rework step e. When there are sub tracking points, there are a plurality of tracking points that should pass before a certain tracking point. Specifically, for the tracking point E, the tracking point C is usually the previous tracking point, but when a defect is found in the overcoating inspection step c, the overcoating rework step e is performed. G is also a previous tracking point. In FIG. 4, the fact that the previous tracking point 1 of the own tracking point E is the tracking point C and the previous tracking point 2 is G indicates this. Incidentally, in the case of the self-tracking point G, the previous tracking point may have been subjected to the overcoating process e in the last time, so three of C, D, and G are defined as the previous tracking points. Of course, the distinction between main and sub is arbitrary, and in a production line that does not include a rework process, one previous tracking point may be defined for the own tracking point.
[0020]
As described above, in this embodiment, the relationship between the tracking point and the process elements existing thereafter, and the relationship between the tracking points are specified, and when a vehicle passes the tracking point, these relationships are referred to as appropriate. By doing so, it is possible to determine what processing the vehicle should go through next, and it is also possible to reliably grasp the production progress status by comparing the original processing state with the current processing state. Then, by modeling the production line using process elements and tracking points, even when the production line is changed, the relationship between the tracking points and the process elements and the relationship between the tracking points are changed according to this change. Therefore, it can be easily handled. In particular, at the branch point of the production line, it is possible to uniquely define the branch by providing a tracking point for each branch path, and at the junction point, the junction can be uniquely defined by providing a tracking point for each junction path. The production process can be easily grasped even in a production line having branching and merging.
[0021]
FIG. 5 shows a specific configuration block diagram of the production management apparatus according to the present embodiment. A sensor 10 for receiving passing vehicle information is installed at the tracking point position of the production line, and this sensor 10 detects whether or not the vehicle has passed the tracking point. It is preferable that the sensor 10 detects whether or not the vehicle has passed the tracking point, and at the same time, reads the identification number ID given to a predetermined position of the vehicle and specifies the vehicle type or the like by the identification number. . Data detected by the passing vehicle information reception sensor 10 is supplied to the tracking point passage determination unit 12.
[0022]
In the tracking point passage possibility determination unit 12, vehicle specifications (such as a relationship between an identification number and a vehicle type) stored in advance in the vehicle specification database 22, tracking point information stored in the tracking point information database 24 (the tracking shown in FIG. 3). Based on production process information stored in the production process information database 26 (relationship between tracking points shown in FIG. 4), a vehicle that has passed a certain tracking point originally uses this tracking point. It is determined whether or not the vehicle is to pass. For example, a certain vehicle should pass the tracking point E from the top coating inspection process c and proceed to the multi-color return process d, but if it is determined that the vehicle has passed the tracking point F, it should not pass by itself. Determined. When a vehicle that should essentially pass the tracking point E passes the tracking point E (the fact that the vehicle has passed the tracking point E can be determined from the fact that this vehicle has passed the tracking point C. If this vehicle passes the tracking point D, it will pass the tracking point F). Conversely, it can be confirmed that this vehicle has undergone the overcoating inspection step c. . Tracking point information and production process information can be input by the user using input means such as a keyboard 38 and an input control unit 34 (which distributes input data to each database).
[0023]
When the tracking point passage possibility determination unit 12 determines that the tracking point should be originally passed, the passage fact is supplied to the passage record recording unit 14. The passing record recording unit 14 measures the time when the vehicle passes the tracking point and registers it in the passing record time database 20. On the other hand, the passage record recording unit 14 also supplies the measured passage time to the scheduled passage time calculation unit 16. The scheduled passage time calculation unit 16 performs tracking based on data from the vehicle specification database 22, the tracking point information database 24, the production process information database 26, and the process information database 30 that records detailed process information in each process element. The scheduled time for completing the process existing after the point is calculated. Specifically, based on the tracking point information (see FIG. 3) and production process information (see FIG. 4) in FIG. 3, each process to be performed after the tracking point that the vehicle has passed is extracted, and the tact time in each process is extracted. The scheduled passage time is calculated for each tracking point that passes in the future based on the process information such as the operation rate and the operation time zone. For example, for a vehicle that has passed the tracking point A, a scheduled passage time t1 at the tracking point C, a scheduled passage time t2 at the tracking point E, a scheduled passage time t3 at the tracking point B, and the like are sequentially calculated. The scheduled passage time may be calculated for the main tracking point. This is because the sub-tracking point does not always pass and there is no point in calculating the scheduled passing time in advance. The calculated scheduled passage time is registered in the scheduled passage time database 28, and both the passage result time and the scheduled passage time are output to the production progress status display unit 32.
[0024]
The production progress display unit 32 has a CRT 36 or the like and is arranged for each tracking point of the production line. The production progress display unit 32 arranged at each tracking point displays a scheduled time that the vehicle should reach. In addition, when the vehicle actually passes, the passing actual time is displayed together with the scheduled passing time. Therefore, the user can know in advance when the vehicle should pass by checking the scheduled passage time displayed on the production progress status display unit 32, and compares the scheduled passage time with the past passage time. Thus, the production progress can be easily grasped. For example, the production progress status display unit 32 installed at the tracking point C displays that the vehicle passes next time t1 (this can be said to be a production instruction that the vehicle should pass at time t1). If the vehicle passes, the time t1 ′ is also displayed and the progress can be grasped by comparing t1 and t1 ′. In addition, when a vehicle that should pass through has not yet passed even at the scheduled passage time, a production instruction can be output to the production instruction output unit 18 installed at the tracking point.
[0025]
As described above, in this embodiment, when the vehicle passes a certain tracking point, it is instructed when to pass the tracking point to be passed next, and when it actually passes, Therefore, it is possible to finely manage production by installing as many tracking points as necessary.
[0026]
In the present embodiment, the vehicle has been described as an example of a product flowing through the production line, but the present invention is not limited to this, and can be similarly applied to a vehicle component or other products.
[0027]
Further, in the present embodiment, as shown in FIG. 3 as the relationship between the tracking point and the process element, a certain passing point is associated with the process element existing thereafter, but the present invention is not limited to this. A certain tracking point may be associated with a process element that should exist before that, and a process element that should exist before or after that may be associated with a certain tracking point.
[0028]
Furthermore, in this embodiment, a relationship between a tracking point and a tracking point that should pass before is defined as a relationship between passing points. However, a plurality of tracking points that should pass before a certain tracking point are defined. It is also preferable to store the points in association with each other as a table.
[0029]
The above is the prerequisite technology of this embodiment. By the way, in the above technique, the tracking point information database 24 and the production process database 26 need to define and store not only normal processes but also abnormal processes such as rework. Rules) are enormous. Of course, if all possible relationships are memorized, complete management is possible, but leaks are also expected.
[0030]
Therefore, in the present embodiment, not all relationships are stored in the tracking point information database 24 and the production process database 26, but only relationships during normal processing are stored, and abnormal processing is managed by another abnormal processing database. . Then, the tracking point passage permission determination unit 12 determines whether or not the tracking point passage is permitted under certain specific conditions for a vehicle that has undergone the repainting process. The conditions are as follows.
[0031]
(1) If the tracking point to which the vehicle is currently passing is upstream (in the direction of body start) from the tracking point that has passed recently (immediately before), the vehicle passes unconditionally regardless of the relationship stored in the database. Allow.
[0032]
(2) If the tracking point to which the vehicle is currently passing is located downstream of the tracking point that has passed recently (immediately before), whether or not the vehicle can pass is determined according to the relationship stored in the database.
[0033]
In the present embodiment, the reworked vehicle is considered as a separate vehicle. However, the vehicle that returns to the previous process for reworking goes through the same process as that of a normal vehicle, and therefore the condition (1) is necessary. It becomes. In other words, if there is no condition (1), the repaired vehicle is not stored in the database, and therefore, the passage is uniformly rejected and the repair becomes impossible.
[0034]
However, if an upper limit is set for the number of passages for the tracking point in the tracking point information database 24, it is necessary to determine whether or not the passage is allowed according to the upper limit.
[0035]
FIG. 6 shows a processing flowchart of the present embodiment. In the figure, it is assumed that A, B, and C exist as tracking points, and that the vehicle has already passed the tracking point A and then attempts to pass the tracking point B.
[0036]
First, the passing vehicle No. (S101), vehicle no. Based on the above, the specification data of the passing vehicle is acquired from the vehicle specification information database 22 (S102). Next, the passing record of the vehicle is acquired from the passing record recording unit 14 (S103), and it is determined whether or not the tracking point B to be passed is a point that has passed in the past (S104).
[0037]
If it is a point that has passed in the past, whether or not the tracking point B is a tracking point that can be passed multiple times is acquired from the tracking point information database 24 (S105), and whether or not the upper limit of passage is satisfied. Determine (S106). If tracking point B is a tracking point that allows only one pass, or if it is allowed to pass twice but this time is the third pass, it is determined that it cannot pass (S111), a command to refuse passage is output from the production instruction output unit 18 (S112). On the other hand, when the upper limit of passage is satisfied, production process information is acquired from the production process database 26 (S107). Further, when the tracking point B to be passed is a point that has not passed in the past, production process information is similarly acquired from the production process database 26 (S107). Then, it is determined whether or not the tracking point B to be passed is located on the upstream side of the production process with respect to the tracking point A that has passed immediately before (S108). If it is located on the upstream side, it means that the process is a rework process, so that the passage of tracking point B is permitted even though it is not defined as production process information (S109), and a production instruction is output to that effect. The data is output from the unit 18 (S112).
[0038]
On the other hand, when tracking point B to be passed is not on the upstream side, that is, located downstream of tracking point A that has passed immediately before (NO in S108), tracking point B to be passed next is the production process. It is checked whether or not it is defined as the upper regular route (relationship during normal processing) (S110). If it exists in the production process, it is determined that it can pass, and if it does not exist in the production process, it is determined that it cannot pass, and is output from the production instruction output unit 18 (S111 and S112).
[0039]
Thus, in the present embodiment, the retouching process is not stored in the database, but is processed separately, the relationship is stored only for normal processing, and the tracking point that is about to pass from now on is regarded as a reworking vehicle. Even if it does not exist, production can be managed with a simple database by allowing passage.
[0040]
FIG. 7 shows the relationship between the production process (A) when both the normal process and the abnormal process (rework) process are made into a database, and the production process (B) when only the normal process is made into a database. . In the figure, M indicates a main tracking point, and S indicates a sub-tracking point. In (A), it is necessary to define the sub-tracking point 202 that is returned to the previous process by reworking, and the tracking point 204 that passes during the reworking process. In (B), it is necessary to define tracking points that accompany such reworking. You can understand that it is a simple database.
[0041]
【The invention's effect】
As described above, according to the present invention, production lines can be managed with simple rules.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a production process in an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a relationship between a passing point and a process element used for modeling a production line.
FIG. 3 is an explanatory diagram of a table defining a relationship between passing points in the present embodiment.
FIG. 4 is an explanatory diagram of a table for defining a relationship between passing points in the present embodiment.
FIG. 5 is an overall configuration block diagram according to the present embodiment.
FIG. 6 is a processing flowchart of another embodiment.
FIG. 7 is an explanatory diagram of a production process according to another embodiment.
[Explanation of symbols]
11 process elements, 100 tracking points.

Claims (4)

Means for storing a relationship between the tracking point and a relationship between the tracking point and the process element for each product when a production line is modeled by a process element and a tracking point connecting the process elements to each other;
Means for controlling the production line based on the relationship between the tracking points and the relationship between the tracking points and the process elements;
With
The means for storing stores the relationship at the time of normal processing without storing the relationship at the time of abnormal processing ,
The control means determines whether or not the product can pass the tracking point based on the relationship, and controls the tracking point to which the product is going to pass, on the downstream side of the production line with respect to the tracking point that passed immediately before. If it exists, use the relationship stored in the storing means to determine whether or not the product can pass, and the tracking point to which the product is going to pass is located upstream of the production line than the tracking point that passed immediately before. If present, the production management apparatus permits passage of the product regardless of the relationship stored in the storing means . The apparatus of claim 1.
The production control apparatus according to claim 1, wherein, when the number of passages of the tracking point through which the product is going to pass is limited, the control unit determines whether or not the product can pass based on the number of passes. Model production lines with process elements and tracking points that connect the process elements together,
The relationship between the tracking points for each product and the relationship between the tracking points and the process elements are stored in a computer memory,
The products are sequentially processed on the production line by outputting instructions from the computer to an output device provided at a predetermined position on the production line based on the relationship between the tracking points and the relationship between the tracking points and the process elements. A product production method using a computer ,
The memory stores the relationship during normal processing without storing the relationship during abnormal processing as the relationship,
The computer determines whether the product can pass the tracking point based on the relationship and outputs the instruction, and the downstream side of the production line is downstream of the tracking point at which the tracking point to which the product is about to pass has passed. In the case where the product is present in the memory, it is determined whether the product is allowed to pass using the relationship stored in the memory, and the tracking point to which the product is to pass is located upstream of the tracking point through which the product has just passed. If so, a product production method is characterized in that an instruction is output to permit passage of the product regardless of the relationship stored in the memory . The method of claim 3, wherein
When the number of passages of the tracking point through which the product is going to pass is limited, the computer determines whether or not the product can pass based on the number of times and outputs the product.

Images