JPH0479776B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ranking control method in a mixed production line, such as an automobile assembly line, in which a plurality of types of products of different vehicle types are mixed and sent through the production line.

Automobile production lines usually consist of a welding process, a painting process, an outfitting process, etc. However, due to sales policies and market demands, there are so-called mixed production lines in which multiple types of cars with different specifications are produced on the same production line. A production line method is adopted.

As a result, there is a problem in that the number of man-hours in each process differs depending on the vehicle model. Therefore, it is possible to level the production order and balance the man-hours, but the demands for leveling of each process such as welding, painting, and outfitting do not necessarily match, and it is difficult to create a consistent leveling order for each process. It is. Moreover, even if a consistent leveling order could be created for each process, rework is unavoidable in the welding process and painting process. When making such modifications, the production vehicle is immediately removed from the production line and then rejoined the production line after the modification, which changes the predetermined production order and makes it impossible to maintain the leveled order. There is a problem.

Therefore, in the past, a method has been adopted in which storage is provided between each process, the produced car bodies are stored by type, and then reassembled to meet the requirements of the next process. However, it is very difficult to rearrange the storage between each process, and storing products by type breaks the entire predetermined production order, which tends to amplify the disorder in the order. Furthermore, storing produced vehicle bodies by type requires a large storage space, making it difficult to manage the produced vehicle bodies.

This invention was made in view of the above-mentioned circumstances, and its purpose is to ensure that the production is carried out according to a predetermined production order, and that the production order is disrupted due to branching, merging, etc. in the upstream production process. Another object of the present invention is to provide a method for controlling the order in a mixed production line, which allows the production order to be adjusted to the production order or a similar order in storage, and to be sent to the downstream production process.

That is, the present invention provides a storage at a relay point between an upstream production process and a downstream production process in which a plurality of types of products with different production conditions are passed in the order of their production order, and stores the products carried out from the upstream production process in the storage. In a mixed production line where the storage is temporarily stored and then transported to the downstream production process, the storage is stored in multiple rows of first-in, first-out storage lanes with designated priorities, and the production lines that are installed in parallel on the same storage lane and are stored in the same storage lane. It consists of an express lane that transports manufactured goods from the upstream production process to the downstream production process with priority over goods, and a forwarding lane that transports the manufactured goods discharged from the storage lane to the storage side again, and each of the above-mentioned manufactured goods. The first basic principle is to assign serial numbers to the storage lanes in order of their production order, and to prioritize the products carried out from the upstream production process and store them in the storage lane in descending order of number. When the production order is disrupted due to merging, etc., if there is a production product with a younger number than you at the end of the production products already stored in the storage lane, the production order closest to you among them The second principle is that if there is no produced product with a lower number than the produced product that is placed in stock after a produced product, the product is stored in an empty storage lane where no produced product is stocked, and if there is no empty storage lane and the The fourth principle is that when a product with a lower number than all the products already in the storage lane is stored in the storage, it is introduced into the above-mentioned express lane and taken out first. At the end of the produced goods,
If there is no production product with a lower number than the product stocked from the above-mentioned upstream production process and there is no empty storage lane, the production order will be higher than that of the product stocked above among the production products already stocked for each storage lane. Search for a product with a large number and a production sequence number closest to the product to be stocked, and place the product from the above upstream production process into the storage lane where the product with the highest production sequence number is stored. The fifth principle is to store the production goods to be stocked, and if the smallest production product in the production order among the production goods already stocked in the storage lane is in the second or later from the front row of the same storage lane, then the The sixth principle is to unload the manufactured goods in front of the smallest manufactured goods from the same storage lane and forward them to the receiving side again via the forwarding lane, and to take out the above-mentioned minimum manufactured goods with priority. , the gist of this is a method for controlling the order in a mixed production line, which is characterized in that the products are ordered in accordance with the second, fourth, fifth, and sixth principles and then delivered to the downstream production process. It is.

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

1 is an upstream production process such as a painting process; 2 is an upstream production process such as a painting process;
is a downstream production process such as an outfitting process.
A storage 3 is provided between the carry-out section 1a of the upstream process 1 and the carry-in section 2a of the downstream production process 2. The upstream production process 1 and the downstream production process 2 consist of belt conveyors that run at low speed (2 to 3 m/min), and are configured to convey multiple types of products A, such as automobiles, with different vehicle types, colors, etc. In the upstream production process 1, specified painting work is performed on the product A, and in the downstream production process 2, parts attachment work is performed on the finished product A. Furthermore, the above-mentioned product A... is given a serial number of 〇n according to the production order required from the viewpoint of sales policy, market demand, etc., and the product A... flowing through the upstream production process 1 is Basically, they are transported in the order of the lowest number. The storage 3 is composed of a plurality of rows, for example, first to fifth storage lanes 4a to 4e, and conveyors 7 that run only in the direction from the storage row 5 to the exit row 6 are arranged in parallel. These conveyors 7 are divided into first to fifth stages 8a to 8e from the output side 6 to the input side 5, and each of the first to fifth stages 8a to 8e is divided into stages 8a to 8e. Article A... can be temporarily stored on a first-in, first-out basis. Further, an express lane 9 and a forwarding lane 10 are arranged in parallel in the first to fifth storage lanes 4a to 4e. This express lane 9 is connected to the first to fifth storage lanes 4.
The product A is transported in the same direction as a to 4e, and the product A is carried from the upstream production process to the downstream production process with priority over the product stored in the first to fifth storage lanes 4a to 4e. do. The forwarding lane 10 transports the product A in the opposite direction to the first to fifth storage lanes 4a to 4e.
The produced articles are stored in the third storage lane 4c, where the produced articles A discharged from a to 4e are transferred to the storage side again. In addition, for each storage lane 4a to 4e, a search is made for a product that has a higher production order than the product that is to be stored above among the products that have already been stored, and that has a production order that is closest to the product that is to be stored above, and among them. The fifth principle is to store the manufactured goods in the third storage lane 4c where the manufactured goods with the highest production order are stored.

The purpose of the fifth principle is that, according to the sixth principle described below, the forwarded product is re-stocked and forwarded, taking into account the time delay until it becomes ready for shipping to the downstream production process. The aim is to maximize the time margin until the manufactured goods are shipped to the downstream production process. In other words, in this embodiment, the product with the highest production order among the products already stored in the first to fifth storage lanes 4a to 4e is , and when the product is delivered to the downstream production process in the order of the production order, will be the final shipment. Therefore, there is sufficient time to forward the produced goods to the warehousing side via the forwarding lane 10 and store them again, and the produced goods can be warehoused in the third storage lane 4c where the produced goods are being stocked. By doing so, the produced articles can be guided to the leading edge of the third storage lane 4c by forwarding the produced articles.

In this way, storage 3 controlled by the above storage method is provided between the upstream production process and the downstream production process.
By providing this, as shown in FIG. 2b, products that have been extremely delayed in the upstream production process can be first discharged from the express lane 9, and then from the first to fifth storage lanes 4a. It is possible to leave the warehouse in ascending order of numbers from 4e onwards.

In addition, the first to fifth storage lanes 4a to 4
Among the production goods A already stored in e, the one with the lowest production order is stored in each storage lane 4a to 4e.
For example, if you are in the second or subsequent row from the front row of
As shown in FIG. 2C, if there is a storage device in the first stage of the third storage lane 4c and there is something to be delivered behind it, it will be delivered and then forwarded to the receiving side by the forwarding lane 10. The sixth principle is to give priority to the smallest product in the production order.

Here, the effects of the fifth basic and the sixth basic will be further explained based on FIG. 2b described above.

FIG. 2b shows that the produced goods are stored in the third storage lane 4c based on the fifth principle as described above, but when the produced goods are to be discharged, the produced goods are stored in the third storage lane 4c based on the sixth principle. After being forwarded through the forwarding lane 10, the goods are taken out of the warehouse.

If we look at the time margin for the forwarded product to be re-stocked and ready for delivery to the downstream production process based on the difference in production order from the production product currently being delivered to the downstream production process, in this case 6 ( −). On the other hand, if produced goods are stored in storage lanes 4b, 4d, and 4e other than the third storage lane 4c without following the fifth principle, the produced goods to be forwarded will be stored in the second storage lane 4b. When the goods are stocked in the 4th
When it is stored in the fifth storage lane 4b, it becomes a production article, and when it is stored in the fifth storage lane 4e, it becomes a production article. That is, the produced goods are stored in storage lanes 4b other than the third storage lane 4c, without being based on the fifth principle.
The difference in ranking between the produced goods that are sent to 4d and 4e is (-) and 5, respectively.
(-), 1 (-), and the above-mentioned difference in rank is smaller than when warehousing is carried out based on the fifth principle. In other words, by warehousing based on the fifth principle, it is possible to maximize the amount of time it takes for the produced goods to be forwarded according to the sixth principle to be warehoused again and ready for delivery to the downstream production process. have an effect.

Here, in comparison with other conditions, in the case of condition 1, "among all the production goods already stocked in the storage lane, the production sequence number is higher than that of the production goods to be stocked, and the production of the production goods to be stocked is The production goods received from the upstream production process are stored in the storage lane where the production goods closest to the sequence number are stored.'' There is the following problem. In other words, if the product to be warehoused is A and the product that meets the above conditions is B, then if the difference in production order between product A and product B is small, product B will be forwarded in the forwarding lane. While the product is in stock, product A is delivered and product B is delivered.
As a result, product B cannot be delivered in the correct order.

In the case of condition 2, "Among all the produced products already stored in the storage lane, the X (for example, 3rd) largest (smallest) product in the production order is received from the upstream production process into the storage lane. There is a possibility that the same problem as in condition 1 will occur.
By determining the storage lane for warehousing based on the above-mentioned fifth principle, it becomes possible to select the optimal storage lane that allows sufficient forwarding time for forwarding the manufactured goods that have already been stored.

Furthermore, as shown in Figure 2d, the forwarding lane 1
Forwarded by 0 is the second warehousing method described above.
The fourth storage lane 4d according to the basis of
By putting the item in the warehouse again, it can be taken out again.

In the above embodiment, one express lane 9 and one forwarding lane 10 were provided, but the present invention is not limited to this, and a plurality of lanes may be provided.
The product is not limited to automobile bodies, but can be applied to any production line as long as multiple types of products of different models are mixed and flowed through the production line.

As explained above, in this invention, storage consisting of multiple rows of storage lanes is
Based on the third principle, the products carried out from the upstream production process are arranged in order of production order or in a state close to this and then delivered to the downstream production process, so the production order is maintained by branching, merging, etc. This has the effect that even if turbulence occurs, it can be rectified in the storage and flowed to the downstream production process.
Furthermore, storage consisting of multiple rows of storage lanes plus express lanes and forwarding lanes can be implemented based on the first and second basics and the fourth, fifth, and sixth basics to store manufactured goods in the order of production order or according to the production order. It can be rectified to a similar state. In other words, if the product is received based on the fifth principle, and the product to be forwarded according to the sixth principle is in the storage, the product to be forwarded will be forwarded to the warehousing side by the forwarding lane and returned to the storage. It is now possible to store production parts in a storage lane that maximizes the time between when they are received and when they can be sent to the downstream production process, making it more effective to prevent disruptions in the production order. Can be rectified. In addition, when production parts are extremely delayed in the upstream production process, the express lane can be used to fully respond, and by using the forwarding lane, it is also possible to correct the shipping order within the same storage lane. This has the special effect of making it possible to improve the rectification effect.

[Brief explanation of drawings]

The drawings show one embodiment of the invention.
The figure is a schematic plan view of the production line, and FIGS. 2 a to 2 d are action explanatory views. 1...Upstream production process, 2...Downstream production process, 3
...Storage, 4a-4e...Storage lane, A...Production parts, 9...Express lane, 10...
...Forwarding lane.

Claims (1)

[Claims] 1 Storage is provided at a relay point between an upstream production process and a downstream production process where multiple types of products with different production conditions are passed in the order of their production order, and after temporarily storing the products carried out from the above-mentioned upstream production process in the storage. , in a mixed production line that transports goods to the downstream production process, the above storage is prioritized over multiple rows of first-in, first-out storage lanes with designated priorities, and over manufactured goods stored in parallel to the same storage lane and stored in the same storage lane. The system consists of an express lane for transporting manufactured goods from the upstream production process to the downstream production process, and a forwarding lane for transporting the manufactured goods discharged from the storage lane to the receiving side again. The first principle is to sequentially assign serial numbers and prioritize the products carried out from the upstream production process and store them in the storage lane in descending order of number. When a disorder occurs in the order, if there is a product with a lower number than you at the end of the products already stocked in the storage lane, the product will be transferred to the product with the closest production order to you. The second principle is that if there is no produced product with a smaller number than you when it is subsequently stocked, it will be stocked in an empty storage lane where no produced products are stocked.
When there is no empty storage lane and a production product with a lower number than all the production products already stored in the storage lane is stored in the storage, the fourth step is to introduce it into the express lane and let it leave the storage first. As a general rule, if there is no product with a lower number than the product that is received from the above-mentioned upstream production process at the end of the product that has already been stocked in the storage lane, and there is no empty storage lane, each storage lane will be , the production items that have already been stocked are discontinued, and the production items whose production sequence number is higher than the production items to be stored and which are closest to the production items to be stored are taken, and among them, the production items whose production sequence is The fifth principle is to store the product that is received from the above-mentioned upstream production process into the storage lane where the product with the highest number is stored, and to store the product that is received from the above-mentioned upstream production process into the storage lane where the product with the highest number is stored. When the number of produced products is in the second or subsequent rows from the front row of the same storage lane, the produced products in front of the smallest produced product are taken out from the same storage lane and forwarded to the receiving side again by the forwarding lane, and the above-mentioned smallest product is The sixth principle is to give priority to the goods to be released from the warehouse, and according to the first, second, fourth, fifth, and sixth basics, the goods are ordered and transferred to the downstream production process. A method for controlling a hierarchy in a mixed production line characterized by importing goods.