JP3364927B2 - Production control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a production line, and more particularly to a production control device for a production line that assembles a plurality of parts into one product.

[0002]

2. Description of the Related Art Conventionally, a method of managing a production line for assembling a plurality of parts into one product is to synchronize with the progress of the main line so that a necessary number of parts can be secured when the parts are needed in the main line. A so-called synchronous method is known in which the assembly of parts is started by using the so-called synchronization method.

This system is a production system in which the production of a component is started when the product requiring the component reaches a process corresponding to the lead time of the component before the mounting process. However, in this method, it may be difficult to establish synchronization when a plurality of types of parts are produced on one part production line or when there are multiple types of products assembled on the main line and lead times differ depending on the type. is there.

In particular, when a product defect occurs and the lead time fluctuates, it becomes more difficult to synchronize. In order to solve this point, the so-called Kanban system has been put into practical use. This method attaches a kanban to the parts, and when the parts are used in the main line, the kanban is removed and collected.

Then, in the parts production line, parts are produced in accordance with the recovered Kanban. However, in the Kanban system, the number of parts to be stored has to be increased in a state where the main line for attaching the parts to the product does not pick up the parts in a uniform cycle, resulting in a problem that the storage place becomes large.

In order to solve this problem, there has been proposed a method in which the production line is controlled by a computer (for example, Japanese Patent Laid-Open No. 2-38193).

[0007]

However, generally, in the case of controlling a production line using a computer, data stored in a buffer (start time of the main line, lead time, etc.) is processed by a condition determination process represented by a flow chart. Since most of the processing is performed, the processing is complicated, and if the program itself needs to be modified due to a change in the determination condition or the production line, the change takes a lot of time.

Further, since the production of the parts is started in the order of high priority in accordance with the progress of the production of the parts production line, it is difficult to detect and manage the delay when the parts production line is congested, and conversely. in the case of parts production line is too proceed too much to make the parts, it is impossible to carry out a proper production while ensuring the proper inventory at all times. Furthermore, if the lead time fluctuates due to rework of defective products in the main line, for example, when setting data based on the shortest lead time, the parts corresponding to the product whose lead time has become longer due to rework The number of stored items will increase.

The present invention has been made in view of the above problems, and not only has a structure in which each main line is modularized and can flexibly deal with line changes,
It is an object of the present invention to provide a production control device for a production line, which makes it possible to produce necessary parts when needed and can easily achieve synchronization with the main production line.

[0010]

FIG. 1 is a basic configuration diagram of a production control apparatus according to the first invention, and FIG. 2 is a basic configuration diagram of product information processing means and parts information processing means. First
The production control device according to the invention of the present invention indicates the specifications of the product produced by combining the main part manufactured on the main line and the sub-part manufactured on the sub-line, and reads the product information attached to the main part to read the main part. The main part information processing means for outputting product information at a time difference according to the specification difference, and the product information output at a time difference according to the main part specification difference from the main part information output means are inputted to respond to the sub part specification difference. The sub-part information processing means for outputting product information with a time difference and the product information output with a time difference according to the sub-part specification difference from the sub-part information processing means are input to determine the difference between the main part production time and the sub-part production time. A production control device comprising: output means for outputting product information as a sub-parts production start command at a time lag corresponding to the main parts information processing means. The product information read from the parts and corresponding to the main part is taken into a predetermined gauge of a plurality of gauges, and the main part information shift block that shifts to the subsequent gauge at predetermined timing sequentially and the main part information shift block is shifted Within the main component information shift block as the production time of the main component information lead block that reads the main component specification information included in the product information and the main component that corresponds to the main component specification information read by the main component information lead block increases The main reading gauge setting block that sets the reading gauge to read the shifted product information from the gauge after the main parts information shift block, and the main reading gauge setting block that shifts the product information in the main parts information shift block Set in A main part information output block that outputs the product information when it reaches the reading gauge, and the sub-part information processing means sets the product information output from the main part information output block to a predetermined number in a plurality of gauges. A sub-part information shift block that takes in a gauge and sequentially shifts to a subsequent gauge at a predetermined timing, and a sub-part information lead block that reads sub-part specification information included in product information that is shifted in the sub-part information shift block, As the production time of the sub-part corresponding to the sub-part information read information read by the sub-part information lead block is shorter, the product information that is shifted in the sub-part information shift block is read from the gauge after the sub-part information shift block. Sub-reading game to set reading gauge A setting block and a sub-component information output block that outputs the product information when the product information shifted in the sub-component information shift block reaches the reading gauge set in the sub-reading gauge setting block, The output means fetches the product information output from the sub-part information output block into a predetermined gauge of a plurality of gauges, sequentially shifts to a subsequent gauge at a predetermined timing, and issues a sub-part production start command from the last gauge. And an output product information output block having gauges corresponding to the manufacturing time difference between the main part and the sub-part.

FIG. 3 is a block diagram of a production control apparatus according to the second invention, which is work-in-progress information processing means installed between the main component information processing means and the sub-component information processing means. Product information output from the information output block is taken into a predetermined gauge in a plurality of gauges, and a work-in-process shift block that sequentially shifts to a subsequent gauge at predetermined timing, and a product that is shifted in the work-in-progress information shift block The in-process sub-part information lead block that reads the sub-part specification information in the information and the sub-part shift information that corresponds to the sub-part specification information read in the in-process sub-part information lead block Set the reading gauge to read the product information to be shifted from the gauge in the latter stage of the in-process product information shift block. In-process reading gauge setting block and in-process product information shift block When the product information that is shifted reaches the reading gauge set in the in-process reading gauge setting block, the product information is output to the sub-part information shift block. In-process product information processing means including an in-process product information output block.

[0012]

In the first aspect of the invention, the main component information processing means reads the product information according to the lead time caused by the specification difference of the main component, and the sub component information processing means causes the difference of the specification of the sub component. Product information is read according to the difference in lead time, and a sub-part production command is output in consideration of the difference in specifications between the main part and the sub-part and the difference in lead time between the main part and the sub-part.

Further, in the second invention, the production amount of the sub-components supplied to the main line by the work-in-process information processing means is further taken into consideration to minimize the inventory of the sub-components.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 4 is a block diagram when the production control device according to the present invention is applied to an automobile production line. The production line is a painting step 4011 for painting a vehicle body which is a main component.
And a main line 401 having an assembly step 4013 for attaching a bumper which is a sub-component to the vehicle body, and a sub line 402 for producing the bumper. Main line 4
A reading device 4012 for reading vehicle information recorded on a magnetic card attached to each vehicle body on the line is installed at the entrance of the painting process 4011 of 01.

The vehicle information read by the reading device 4012 is transmitted to the assemble line controller 405 via the host bus 404, and the vehicle body painting specifications and the front and rear bumper painting specifications are read by using the vehicle information as a keyword. It is sent to the information computer 403. FIG. 5 is an example of a configuration diagram of vehicle information including painting information. The body number is from the 0th bit to the 5th bit and the front bumper painting specification is from the 29th bit to the 38th bit. Rear bumper coating specifications are stored from the 39th bit to the 48th bit, and vehicle body coating information indicating whether the vehicle body of the vehicle is two-tone color or monocolor is stored at the 50th bit.

It should be noted that the painting specifications of the vehicle body and the bumper are directly recorded on a magnetic card attached to the vehicle body and may be read directly from the vehicle body without passing through the assemble line controller 405. It may be a remote ID, a bar code or the like instead of the card. FIG. 6 is a configuration diagram when the production control device according to the present invention is applied to the present embodiment. In the vehicle information computer 403, the vehicle information shifter 601 which is the main component information processing means 101 is configured, and work in progress is performed. In the management computer 407, a delay shifter 602 which is an in-process information processing means 102, a bumper shifter 603 which is a sub component information processing means 103, and an output shifter 6 which is an output means 104.
04 is configured.

Vehicle information shifter 601 and bumper shifter 60
3 and the delay shifter 602 have the same structure and are composed of a shift block, a read block, a set block and an output block. That is, the shift block has a plurality of gauges for storing vehicle information, takes the vehicle information into the leading gauge, and sends it to the subsequent gauge at a predetermined shift time. The lead block reads only specific information (for example, front bumper coating specification information) in the vehicle information stored in the gauge. The set block is
When the specific information has a specific value, the gauge number for reading the vehicle information that is shifted in the gauge of the shift block is set. The output block reads out vehicle information from the gauge set in the set block and outputs it. The output shifter 604 is composed of only shift blocks. For the sake of simplicity, the following two types of vehicle body painting will be applied: mono-color and two-tone colors, and bumper types will also be applied, two types: mono-color and two-tone colors. The vehicle information shifter 601 is intended to adjust the difference in lead time between when the vehicle body painting specification is mono-color and when it is two-tone. That is, the vehicle information shifter 601
In the lead block of No. 1, the vehicle body painting information located at the 50th bit of the vehicle information is read. If the set value of the set block is "0" indicating that the 50th bit of the vehicle information is mono-color, the vehicle information is read from the leading gauge G1 of the shift block, and the 50th bit is two-tone color. If it is "1" indicating that, it is set to be read from the nth gauge Gn.

The value of n is obtained from the following equation. n = (T2-T1) / Tt + 1 (1) where T2 is the time it takes to paint the vehicle body in two-tone color T1 is the time it takes to paint the vehicle body in mono-color Tt is the takt time of the main line T1 and T2 are the takt time It is an integral multiple of Tt. Therefore, the vehicle information is immediately read from the leading gauge G1 of the shift block when the vehicle body painting information is mono-color, and the vehicle information is read from the n-th gauge Gn after n · Tc hours in the case of two-tone color. Read. Note that Tc is the shift time of the shifter.

In the present embodiment, the shifter is shifted every tact time Tt at which new vehicle information is input, that is, the tact time of the main line and the shift time of the shifter are equal, so Tc = Tt. Become. For a two-tone car body, it is necessary to paint the car body more than once on the main line, which requires a longer lead time than a mono-color car body. The lead time differs depending on whether there is one.

Therefore, if the bumper production is simply started in the order of inputting vehicle information, that is, in the order in which the vehicle body enters the painting process, accurate synchronization cannot be achieved between the vehicle body manufactured in the main line and the bumper manufactured in the sub line. . In order to solve this point, the vehicle information shifter changes the timing of reading vehicle information according to the difference in lead time due to the difference in specifications of the main parts to achieve accurate synchronization between the main line and the sub line.

That is, a work-in-process instruction to the bumper for a two-tone color vehicle body occurs at a timing delayed by an amount corresponding to the lead time difference in the coating process between the two-tone color vehicle body and the mono-color vehicle body. It achieves accurate synchronization. Even if the vehicle information is read, it is not deleted and the shift is continued.

It is possible that a plurality of pieces of vehicle information are simultaneously read by the leading gauge G1 and the nth gauge Gn.
In this case, two or more vehicle information items are output simultaneously. The vehicle information read by the vehicle information shifter 601 is transmitted to the in-process management computer 407 via the lower-order bus 406 and input to the delay shifter 602. This delay shifter 602 is intended to reduce the stock quantity of sub-components supplied to the main line.

That is, if a bumper having a large amount of production, for example, a bumper of a standard specification, starts production at a timing corresponding to the average coating lead time of the bumper, even if the vehicle is manufactured with the shortest lead time, The required minimum number of bumpers is secured and it is prevented that the bumpers run out. On the other hand, keeping a stock of special-purpose bumpers with a small production volume and a large number of types at all times will result in an increase in the total inventory, so the bumper will be synchronized with the shortest lead time for body painting. It will be necessary to undertake the production of

FIG. 7 is a graph showing the distribution of the lead time from the vehicle body painting process entrance to the bumper installation,
The vertical axis is frequency and the horizontal axis is time. According to this graph, the shortest lead time is Tr, and on average Tr + Tm
It is shown that it is the lead time. Table 1 is a table showing vehicle specifications and lead time categories of the vehicles,
The lead time index 1 indicates that the product is a high-volume product, 2 is a medium-volume product, and 3 is a low-volume product.

[0025]

[Table 1]

Then, for example, the delay of the delay shifter is Tr + Tm for a high-volume product, Tr + 0.5Tm for a medium-volume product, and T for a low-volume product.
Set to r. That is, the set value of the set block of the bumper shifter 603 is set so that the data can be read from the first gauge when it is determined that the bumper is for a small-volume production vehicle body.

When it is determined that the bumper is for a medium-volume production vehicle body, the set value of the set block is set so that the data can be read from the m2 = Tm.multidot. (2.multidot.Tt) +1 (2) th gauge. However, m2 is a known method
Convert to an integer by rounding (for example, rounding). When it is determined that the bumper is for a mass-produced vehicle body, the set value of the set block is set so that the data can be read from the m1 = Tm · 2 / Tt + 1 (3) th gauge. However, m1 is a known method
Convert to an integer by rounding (for example, rounding).

Twice in equations (2) and (3) indicates that two bumpers are required for one vehicle, and 1/2 in equation (2) is for medium-volume production vehicle bodies. For bumpers of Tm /
This is to set a delay of 2. Further, the expression (3) indicates that a delay of Tm is set for a bumper for a mass-produced vehicle body. As a result, the bumper for small-volume production vehicle bodies will start production without delay relative to the production of vehicles, and as the production volume of vehicles increases, the in-process instruction of the bumper will be delayed relative to the lead time to minimize the total inventory amount. It becomes possible to limit it.

The data read from the delay shifter 602 is transmitted to the bumper information shifter 603 that is configured in the same widget Ri in the management computer 407. The bumper information shifter 603 is for adjusting the lead time between the two-tone color bumper and the mono-color bumper. In the present embodiment, the gauge number k of the bumper information shifter 603 is determined by the following formula.

K = (Tb2-Tb1) / Tt × 2 + 1 (4) where Tb2 is the lead time Tb1 of the two-tone bumper, Tb1 is the lead time Tt of the monocolor bumper, Tt is the takt time Tb1 and Tb2 is half the takt time, That is, Tt / 2
Is an integer multiple of . And in the bumper information shifter,
Vehicle information corresponding to the monochrome bumper is read from the k-th gauge, and vehicle information corresponding to the two-tone bumper is read from the first gauge.

A gauge may be additionally provided on the bumper information shifter 603 so that it can correspond to special specifications other than mono-color and two-tone color. In this case, the difference between the gauge that reads the mono-color information and the gauge that reads the two-tone color information is k. From the difference between the lead time of the two-tone color bumper and the lead time of the special specification bumper before the gauge that reads the two-tone color information. Add a fixed number of gauges.

The data output from the bumper information shifter 603 is transmitted to the output shifter 604 which is also configured in the work-in-progress management computer 407. This output shifter 6
Reference numeral 04 is provided to adjust the lead time difference between the vehicle body which is the main component and the bumper which is the sub component. The number h of gauges of the output shifter 604 is determined by the following equation. h = {(T1-Tb1) × 2 / Tt + 1} -kmax (5) where T1 is the coating lead time of the mono-colored vehicle body, Tb1 is the production lead time of the mono-colored bumper kmax is the maximum number of gauges of the bumper information shifter. It should be noted that twice the value of equation (5) means that one vehicle body requires two front and rear bumpers. Also the car body
Coating lead time T1> Bumper production lead time T
It is b1.

The output shifter 604 has a
The vehicle information that should be produced on the production line is
And the buffer is ordered from the last stage as a bumper manufacturing start command.
Output to the user 4021. Buffer 4021 is input
The vehicle information is stored in the order of production, and the instruction terminal 4022
When the production of one bumper started
Since it is read from the buffer 4021, the predetermined timing
It is possible to produce bumpers with specified specifications. That is, an increase in the storage amount of the buffer 4021 means a delay in the production of parts, and when the buffer 4021 is empty, it means that it is not necessary to produce parts.

When the bumper production line is on standby, it is possible to perform preproduction under control by sequentially prefetching the output shifter 604. Although the specific information read in the read block 220 and the value set in the set block 230 are directly compared in the above description, new specific information is read using the read specific information as an argument, and It is also possible to compare with the set value.

In the above description, the case where there is one main line has been described, but when there are a plurality of main lines, the above 4
A production control device consisting of two shifters may be installed in correspondence with the main line. Further, even when there are a plurality of sub-lines, it is possible to deal with this by distributing the output of the component information processing means for each sub-line.

Further, the material such as steel plate must be arranged before the product is put on the production line, but it is suitable by constructing the simulator of the process before actually getting on the production line in the production control device according to the present invention. It is also possible to use so as to arrange an appropriate amount of materials and the like at various times. It should be noted that if there is no great difference in the production amount depending on the type of the parts and the inventory quantity of the parts can be maintained within an appropriate range, the work-in-process delay may not necessarily be installed.

Further, in the above description, the production control device is configured by software in the computer to form the shifter, but the production control device may be constructed by combining the shifters by hardware.

[0038]

According to the present invention, not only can the sub-components be supplied to the main line in consideration of the difference in the lead time caused by the specifications of the main components, the difference in the lead time caused by the use of the sub-components, and the production amount. It is possible to supply the sub-components to the main line at an optimum timing while keeping the total inventory quantity of the sub-components to a minimum.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a production control device according to a first invention.

FIG. 2 is a basic configuration diagram of an information processing means in the production control device according to the first invention.

FIG. 3 is a basic configuration diagram of a production control device according to a second invention.

FIG. 4 is a configuration diagram of an automobile production line.

FIG. 5 is a configuration diagram of vehicle information.

FIG. 6 is a configuration diagram when applied to an automobile production line.

FIG. 7 is a diagram showing a lead time distribution required for painting a vehicle body.

[Explanation of symbols]

101 ... Main part information processing means 103 ... Sub-part information processing means 104 ... Output means 210 ... shift block 220 ... Lead block 230 ... set block 240 ... Output block

Claims (2)

(57) [Claims] 1. A main part specification difference indicating a specification of a product manufactured by combining a main part manufactured on a main line and a sub part manufactured on a sub-line, and reading product information attached to the main part. The main part information processing means for outputting product information with a time difference according to the above, and the product information output with the time difference according to the main part specification difference from the main part information output means The sub-part information processing means for outputting product information with a time difference, and the product information output with a time difference according to the sub-part specification difference from the sub-part information processing means are input to determine the main part production time and the sub-part production time. An output means for outputting product information as a sub-parts production start command at a time difference according to the difference, and the main parts information processing means, The product information read from the main parts is loaded into a predetermined gauge in a plurality of gauges, and a main part information shift block that sequentially shifts to a subsequent gauge at predetermined timing, and the inside of the main part information shift block. The main component information lead block that reads the main component specification information included in the shifted product information, and the longer the production time of the main component corresponding to the main component specification information read by the main component information lead block, the more the main component A main reading gauge setting block for setting a reading gauge to read the product information shifted in the information shift block from the gauge at the latter stage of the main component information shift block; and the product information shifted in the main component information shift block. But the main reading gauge When the reading gauge set in the setting block is reached, the main component information output block outputs the product information, and the sub component information processing means outputs the product information output from the main component information output block. To a predetermined gauge of a plurality of gauges, and a sub-part information shift block that sequentially shifts to a subsequent gauge at a predetermined timing; and a sub-part included in the product information that is shifted in the sub-part information shift block. A sub-parts information lead block for reading the specification information, and a shorter production time of the sub-parts corresponding to the sub-parts specification information read by the sub-parts information lead block,
A sub-reading gauge setting block that sets a reading gauge to read product information that is shifted in the sub-component information shift block from a gauge at a stage subsequent to the sub-component information shift block; Product information that is output by the sub-reading gauge setting block when it reaches the reading gauge set by the sub-reading gauge setting block, and the output means outputs the product information by the sub-parts information output block. The product information output from the above is taken into a predetermined gauge of a plurality of gauges, and the main part and the main part that outputs a sub-part production start command from the last-stage gauge by sequentially shifting to the latter-stage gauge at predetermined timing A game with the number of stages corresponding to the difference in production time of sub parts Production control apparatus characterized by being composed of an output product information output block having. 2. A work-in-progress information processing unit installed between the main component information processing unit and the sub-component information processing unit, wherein product information output from the main component information output block is stored in a plurality of gauges. Of a work-in-progress block that is loaded into a predetermined gauge of the work-in-progress and that is sequentially shifted to a subsequent gauge at a predetermined timing; The larger the production volume of the part information lead block and the sub-part corresponding to the sub-part specification information read by the in-process sub-part information lead block, the more product information that is shifted in the in-process shift block becomes Product information The in-process reading gage that sets the reading gage to read from the gage at the latter stage of the shift block. Page setting block and the product information shifted in the in-process product information shift block reach the reading gauge set in the in-process reading gauge setting block, the product information is shifted to the sub-part information shift. The production control device according to claim 1, further comprising an in-process information processing unit configured by an in-process product information output block which is output to the block.