JPH04223826A - Production process management system - Google Patents

Abstract

PURPOSE:To provide a production process management system to allow to distribute correction works to plural correction work stations accurately according to the correction works. CONSTITUTION:A production line which consists of plural work stations 5 to 14, and a correction line which consists of at least one or more correction stations 15 to 19 connected in series to the production line and carrying out correction works are provided. A data carrier is provided to a work W. A device to write a content of unreasonable parts as the result of the working is provided to each work station. Between the production line and the correction line, a reading/distributing unit to read the content of the data carrier, and to make a correction instruction to specify correcting parts and correcting tools depending on the read content is provided. And an instruction device to deliver the correction instructions to the correction stations is also provided.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a work line in which one work station is arranged in the work transfer direction for each type of work to be performed, and a correction method for correcting defects that occur in this work line. The present invention relates to a production process control system having a plurality of stations and consisting of a work line and a correction line connected in series, and particularly relates to an improvement in a process control method thereof.

0002

[Prior Art] In a production line for a predetermined workpiece, such as an automobile assembly line, a computer is installed in various work equipment (e.g., NC equipment for nut runners, welding robots, etc.) arranged in series. The work process is automated by providing a sub-unit for sequence control, and having the host computer perform sequence control on the sub-unit according to the work ID regarding the operations that each piece of equipment should sequentially perform. It is known.

When such sequence control is performed, a sequence control program stored in the memory of the sequence control unit on the host computer side is loaded into the subunit. The subunit is designed to sequentially and rationally control the individual working equipment in the production line for automobiles and the like in accordance with the sequence control program sent from the host computer. As mentioned above, in an automated production line for automobiles, etc., where multiple pieces of equipment to be sequence controlled are arranged, each workpiece transported along the line is processed according to a series of work steps. These operations are sequentially and automatically performed by the plurality of equipments that are subject to sequence control.

[0004] In such a production line, there is actually a possibility that a problem may occur in the result of work performed on a workpiece in each work process. Therefore, an inspection line is usually required for the above-mentioned automated production line in which a plurality of sequence-controlled equipment is arranged. JP-A-61-10 discloses such an inspection line.
There is No. 8079. In the production line (inspection line) of this prior art, a mobile communication device is attached to the car body as a workpiece flowing through the line, and the inspection results of each inspection process are sent by communication and written into the RAM in this communication device. It is now possible to

However, defects do not occur at all positions performed by automatic equipment; in fact, if work is performed at 100 points by a robot at a given work station, Problems may occur in several places. Therefore, providing a special inspection line to detect these few defects will hinder the efficiency of the production line. That is,
It is important to have an inspection line like the one in JP-A No. 61-108079 in the production line, but what is more important is how to inspect for defects without reducing production efficiency.
The question is whether to correct the problem.

[0006] The assembly line is a place where sequence control for assembly is performed, and it is difficult to correct problems that occur there. In practice, most such corrections would be difficult without human intervention. In other words, in order to correct defects without reducing production efficiency,
In addition to the assembly line, a correction line is required.

[0007] Therefore, a continuous line of assembly→inspection→correction is required, but it is not preferable to provide a special inspection line for defects that occur infrequently. Therefore, a continuous line such as an assembly line, excluding an inspection line, and then a correction line can be considered, but there are the following problems.

In other words, since defects occur at each station on the actual assembly line, unless a special line called an inspection line is provided as in the prior art, problems can actually occur only at that assembly line. On top of that, it is not possible to understand the occurrence of defects and the nature of the defects. Therefore, the problem is how to communicate defects detected on the assembly line to the repair line.

The following methods can be considered as methods for detecting defects and transmitting the defects to the correction line.

[0010] In other words, in the conventional sequence-controlled production line described above, there is a central computer system that manages the entire production plan, and each work station is provided with a corresponding sequence control subunit. In a line system, work status data representing the work result status is formed in the subunit corresponding to each sequence control target equipment, and this work result data formed in the sequence control subunit is once integrated into each sequence control unit. data is collected via communication lines into a central system that manages the data, and is analyzed in this central system. When a defect is detected in the central system based on the results of this analysis, data regarding the detected defect can be sent from the central system via a communication line to a data receiving unit installed at the correction work station. .

However, data processing between the sequence control unit, the central system, and the data receiving unit at the correction work station requires a large number of sequence control target equipment installed on the production line and corresponding sequence control units. As the number increases, the amount of processing increases rapidly, requiring a long time.
Furthermore, errors in data processing increase, which may reduce the efficiency and accuracy of the correction work on the workpiece at the correction work station.

0012

[Problem to be Solved by the Invention] Incidentally, in the above-mentioned repair line, a plurality of repair work stations are normally provided in succession corresponding to a plurality of equipment to be controlled in sequence. When a plurality of correction work stations are provided, the following problems occur.

That is, each repair work station naturally has a length corresponding to the body of the automobile (for example, about 4 m). Therefore, it is impossible to correct the entire range of correction points from the front end to the rear end of the vehicle body, which is the object of correction, at one correction work station because the movement range of the operator becomes too large. Therefore, it is necessary to adopt a repair system in which it is necessary to determine which repair work station is to be used to repair which defective part of the vehicle body, and to assign the work to each station.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to propose a production process management system that can accurately distribute correction work to a plurality of correction work stations according to the correction work.

A further object of the present invention is that when a plurality of repair stations are provided on a repair line and repair work is distributed to these stations, if the repair work is not properly completed at any of the repair work stations, In such a case, it is an object of the present invention to propose a production process control system that can execute appropriate correction work at any subsequent correction work station.

By the way, in the above-mentioned repair work station, a plurality of tools are used to perform the repair work. For example, in the case of repair work such as screw tightening, a plurality of torque wrenches with different torque values are provided. In terms of detecting improvements in work efficiency, it is originally preferable in terms of efficiency that the operator does not have to change his/her tool as much as possible.

[0017] A further object of the present invention is to propose a production process control system that allows correction work to be carried out efficiently at a correction work station.

[0018]

[Means for Solving the Problems] A production process control system of the present invention for achieving the above-mentioned problems is a production line having a plurality of work stations that perform productive work on workpieces moving along the line. A production process system for managing production processes carried out by a data carrier provided on the workpiece that moves through the production line and the repair line, detects a defect as a result of the productive work, and writes the contents of the defect to the data carrier. a means for reading the contents of the data carrier provided between the production line and the correction line; and information for specifying a correction point based on the read contents and correction thereof. an instruction means for creating a modification instruction including information specifying a tool to be used for the modification and sending the modification instruction to the at least one modification station, and performing modification work based on the modification instruction sent from the instruction station. and the correction station for carrying out the correction.

In the production process control system of the present invention having another configuration, the instruction station sends a correction instruction to the correction station located next to the instruction station, and each correction station is configured to complete the respective correction work. / Detects incomplete correction work, changes the unfinished correction work to a correction instruction to be performed at the next correction station, and sends this correction instruction to the next correction station using a communication line. and send it.

In the production process control system of the present invention having another configuration, the instruction station sends a correction instruction to the correction station located next to the instruction station,
Each correction station has means for determining whether or not the work has passed the jurisdictional range of its own station, and means for passing the correction instruction to the next correction station when the work has passed the jurisdictional range. It is equipped with.

[0021] In the production process management system of the present invention having another configuration, when each correction station receives the correction instruction from the previous correction station, it displays the passed correction instruction for a predetermined period of time. is displayed on the display means with a delay of .

[0022] In the production process control system of the present invention having another configuration, each of the correction stations includes means for detecting completion/incompleteness of individual correction work at each station, and means for detecting completion/incompleteness of individual correction work at each station, and a means for detecting completion/incompleteness of individual correction work at each station, and a means for detecting the completion/incompleteness of individual correction work at each station, means for disabling the detection means for a predetermined period of time when the detection means is delivered.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an automobile assembly line will be described below with reference to the accompanying drawings.

<Characteristics of the embodiment system> Although not limited to the automobile industry, the characteristics of production lines that typically appear in the automobile manufacturing industry include, for example, an engine production line, a car body production line, a car body painting line, and an engine production line. This means that multiple assembly lines, such as the car body assembly line, are organically linked to continuously produce automobiles. One company may have multiple factories, and some may have only one factory. The production plan for the entire company is managed by a central computer system, and
An entire factory is also managed by a computer dedicated to that factory or by the central computer system mentioned above. The plurality of production lines provided in the factory collectively form one or more continuous lines.

The features of this embodiment are as follows: (1) Each production line is connected to an assembly work line and a line continuously connected to this assembly work line. The system is structured such that it consists of a rework line and a rework line, and any defects that occur on the assembly work line are processed and reworked as much as possible within the framework of the same production line, in other words, without the help of a central system. be. While conventional rework systems were of a centrally managed type, the system of this embodiment can be called a distributed type. For this purpose, this distributed system transmits information about defects that occur on the assembly work line, that is, information about the workpiece where the defect has occurred and defect information such as the location of the defect in the workpiece, to the station where the defect occurred (assembly (There are multiple stations on the work line), the data is temporarily stored in a data carrier that moves with the flowing work. Then, defect information is read from this data carrier just before entering the rework line, and based on this information, what kind of tool is used at which station on the rework line (there are multiple stations on the rework line). Instruct the worker whether or not to carry out rework. (2): The second feature is to use a non-contact type data carrier, and to transmit defect information to this data carrier, or to read it from there. Microwave is selected as the transmission method for this system due to its noise resistance and transmission distance performance. ■: Thirdly, at the rework work station, the CRT
A display device is installed, and according to the graphics displayed on the display device, the system informs the operator of the location of the defect, the type of tool to be used, the order in which repairs should be made, etc. In other words, the worker can clearly see specific instructions for dealing with the problem. ■: 4th
Second, it deals with the so-called "chasing" problem. When humans work on a line where assembly line work is being carried out, the problem is when one worker unknowingly steps into another worker's territory (this is called "chasing").
It is. Therefore, when instructions are given on the display screen, as in this system, to prevent this "chasing" from occurring, the system is designed to make the worker aware that the next work has arrived. It is necessary to forcibly switch the screen from the work instructions for the previous work to the work instructions for the next work. However, since each worker's work speed varies, the screen should not be changed uniformly, but should be changed at a predetermined time (tC) after the next work has entered the worker's area. There is. ■: In order to improve the efficiency of rework work, the system determines the order in which rework work is performed. In addition, we automate the completion detection of individual rework tasks where it is possible to do so. In this system, a torque wrench is used as an example of rework work. The completion of repair work using a torque wrench can be automated by detecting the load applied to the torque wrench. Furthermore, for rework work for which detection of completion cannot be automated, in this system, the operator notifies the system of the end of the rework work by pressing a single completion confirmation button. This kind of automation of end detection is possible because
This is because the rework order is determined by the system. In other words, the system knows which part of the rework work will be completed next, so when you press the end signal or the end confirmation button, it does not know which part of the rework work is actually completed. It can be recognized. Therefore, the problem is how to synchronize the screen switching described in ① with the detection of the completion of individual rework operations. The biggest problem with not being able to synchronize is that parts of the work that are not actually being reworked are recognized as finished. Therefore, in this system, the input of the rework completion signal is prohibited for a predetermined time (tS) after the screen is switched.

This system has various features in addition to the above-mentioned features (1) to (2), and these features will become clear from the configuration and operation of this system, which will be explained in detail below.

[0027] Since this system is like this,
An understanding of the features of this embodiment must begin with an understanding of the relationship between the automobile production line of this embodiment, particularly the assembly line and the rework line.

<Automobile Assembly Line> First, FIG. 1 shows the overall configuration of the automobile assembly line 1 in this embodiment (
The layout configuration of the equipment) is shown.

The automobile assembly line 1 of this embodiment is a final assembly line for automobile bodies. That is, on this assembly completion line, for example, assemblies such as the engine, suspension, fuel tank, radiator, etc. are assembled on the vehicle body, which is suspended and transferred from operating means such as a hanger frame. Automated work in which screw fastening members such as bolts are fastened using a nut runner, for example, and repair work in which defects that occur during the work are manually corrected are performed.

That is, as is clear from FIG. 1, the automobile assembly line 1 can be roughly divided into (1) a station group 1A for carrying in and positioning vehicle bodies (this group includes stations #1 to ##); (2) Station group 1B (this group consists of station #4 and
(3) station group 1C that performs automatic assembly work by robots (this group consists of stations #5 to #14); (4) first backup by human-based work. Rework work station group 1D as a rework line (this group consists of stations #15 to #19, and mainly performs rework on the upper part of the car body), (5) Auxiliary work station for top ceiling tensioning, etc. Group 1E (This group is stations #20 to #21
(6) Rework work station group 1 as a second back-up rework line with another human-based work
F (This group consists of stations #22 to #27, and mainly performs repair work on the lower part of the car body), (7)
Station group 1G (this group consists of stations #28 to #29) that performs the work of returning the assembled vehicle body.
, (8) Station group 1H (this group consists of stations #30 to #
(9) A station group 1I (this group consists of stations #32 to #36) for adjusting parts.

Note that the stations #1 to #39 shown in FIG. 1 are not strictly divided into stations, but merely represent rough positions for the operator.

Positioning station group 1A The station group 1C on which work is performed by the robot includes a positioning station group 1A for positioning the vehicle body carried in, and a carry-in station group 1B for carrying in the parts to be assembled. and has. In the positioning station group 1A, an overhead type vehicle body transfer line 3 (FIG. 1) is provided.
The first guide rail 3a (Fig. 2)
The car body 6, which has been guided and transported in the direction shown in the figure, is first transported to the #1 station in a switchback style. For example, the car body 6 of the car brought in here has been painted, but the parts to be assembled include an engine, suspension, fuel tank, radiator, strut, sliding roof, etc.
Various vehicle components such as the top ceiling have not yet been assembled.

Referring to FIGS. 1 and 2, the vehicle body 6 is moved to the loading guide rail 3a of the vehicle body transfer line 3 via an elevating hanger frame 21 equipped with elevating cylinders 21a, 21a. It is carried in a suspended state to the #1 station position on the positioning station group 1A. Then, from #1 station to #2
In the process of moving to the station, the vehicle body 6 is lowered and placed on a lifter (not shown), and eventually reaches station #3. At this position, accurate positioning of the vehicle body on the lifter and measurement of the positioning state are performed. Then, the vehicle body 6 is next lifted by this lifter,
It is transferred to the #4 station of the next assembly parts carrying station group 1B.

Loading station group 1B Sub-pallets 5a, 5b (
(Fig. 2) is mounted on the sub-pallet mounting station group 1H mentioned above, and is mounted on the component adjustment work station group 1H.
The workpiece adjusted at I is loaded. That is,
Prior to assembly at station #4, subpallet 5a is loaded with subpallet mounting station group 1H.
The engine 14 with the front suspension assembled is mounted on the sub-pallet 5b, and the rear suspension 15 is mounted on the sub-pallet 5b. is to be adjusted accurately. These sub-pallets are mounted on a work pallet (main pallet) 13 for transporting the work, and merge with the vehicle body 6 at the #4 station. That is, as shown in FIG. 2, at the #4 station, the vehicle body 6 suspended by the hanger frame 21 from the left to the right in the paper.
has arrived, and on the other hand, engine 1 mounted on pallet 13
4 and the rear suspension 15 also move in the direction perpendicular to the plane of the paper of FIG. 2 and arrive at station #4.

The line structure of the automobile assembly line 1 after the carry-in station group 1B is as shown in detail in FIGS. 2 and 3, for example, as shown in detail in FIGS. It consists of Work pallet conveyance device 1
7 includes a pair of left and right guide portions 24L, 24R each having a large number of support rollers 23, 23, . A pair of transport rails 25L, 25
R, each has a pallet locking portion 26 for locking the work pallet 13, and the transport rails 25L,
A pair of left and right pallet conveyors 27L, 27R configured to freely move along the conveyor rails 25R, and a linear motor mechanism (not shown) that drives the pallet conveyors 27L, 27R along the conveyor rails 25L, 25R. It is configured.

Automatic assembly station group 1C and, as mentioned above, on the #4 station of carry-in station group 1B, the engine 14 and rear suspension are mounted on the lower side of the vehicle body 6 on the upper side, as shown in FIG. The work pallet 13 loaded with 15 is carried in synchronously. Then, at station #5, which is the first work station on the next automatic assembly work station group 1C side, the car body 6 is lowered by a lifter, and the car body 6 is eventually removed from the lifter, and the right side in FIG. As shown at station #5, both the vehicle body and the parts are docked correctly.

That is, automatic assembly work station group 1
At each station C, when assembling the front suspension and rear suspension 15, the struts of the front suspension (not shown) and the struts 15A of the rear suspension 15 (Fig. 2) are supported and assembled, respectively. A pair of left and right front clamp arms 30L and 30R (FIG. 3) and a pair of left and right rear clamp arms 31L and 31R are provided, respectively, for taking a posture. Then, the left and right front side clamp arms 30L, 3
The 0Rs are formed on the fixed bases 35L and 35R so that they can move, for example, back and forth, left and right, with their tips engaged with the struts of the front suspension. In addition, the left and right rear clamp arms 31L
, 31R are on the fixed bases 37L, 37R, respectively,
With their tips engaged with the struts 15A of the rear suspension 15, they are movable back and forth and left and right. Thus, the left and right front clamp arms 30L, 30R
The left and right rear clamp arms 31L and 31R form the above-mentioned docking device 40.

Each of the assembly stations also includes:
Furthermore, a pair of slide rails 41 are installed to extend parallel to the transport rails 25L and 25R, respectively.
L, 41R, a movable member 42 that slides along the slide rails 41L, 41R, and a slide device 45 that includes a motor 43 that drives the movable member 42 and the like. Moreover, the movable member 42 of this slide device 45
is provided with engagement means 46 for engaging a movable engine support member (not shown) provided on the work pallet 13. The engine 14, front suspension (not shown) and rear suspension 1 arranged on the work pallet 13 are mounted on the body 6 supported by the lifting hanger frame 21 of the overhead type transfer device 16.
5, the slide device 45 moves the pallet 13 in a state in which the engaging means 46 is engaged with a movable engine support member (not shown) on the work pallet 13 positioned by the lifting pallet reference pin 47. Move it back and forth. Thereby, the engine 14 is moved back and forth with respect to the vehicle body 6, and interference between the vehicle body 6 and the engine 14 is avoided.

Each of the assembly stations further includes a robot 48A that tightens bolts or screws for fastening the engine 14 and front suspension (not shown) assembled to the vehicle body 6, and
A robot 48B for tightening bolts or screws for fastening the rear suspension 15 combined with the rear suspension 15 is disposed at each of the robots 48B.

The vehicle body 6 that has been docked with the parts to be assembled on the work pallet 13 is sequentially transferred to each of the work stations #6 to #14 of the assembly work station group 1C at predetermined time intervals.

The assembly work station group 1C constructed with the above structure includes, in addition to the above-mentioned #5 work station, stations #6 to #14 (however, in FIG. 1, #6 For example, 10 units of unit work stations from #13 to #13 (not shown) are provided,
In addition to the docking work (#5) between the vehicle body 6 and the assembled parts such as the engine 14, bolt tightening work (#6) on the engine or front suspension mount, and bolt tightening work (#7) for attaching the fuel tank. ), Bolt tightening work for installing struts (#8), Bolt tightening work for installing rear combination lamps or radiators, etc. (#10), Bolt tightening work for installing sliding roof (#11), etc. Bolt tightening work using various automatic machines such as nut runners is increasingly being carried out using robots such as those mentioned above.

Further, after the assembly work station group 1C, there are work station groups 1D and 1F for revising the assembly work performed at the assembly work station group 1C.
(Station group 1D repairs the upper part of the vehicle, and station group 1F repairs the lower part), and auxiliary work station group 1E located in between them, and the assembled car body, which has also completed the above-mentioned modification work, are reworked in a predetermined manner. A group of vehicle body return stations 1G for transporting or returning vehicle bodies to their respective positions is provided.

When the robot device that tightens bolts and nuts at each assembly station detects an abnormality in the tightening torque, it stops the work and stores the position where the abnormality occurs. This point will be explained in detail in relation to a data carrier, which is a device for storing defect information.

Upper rework work station group 1D This rework work station group 1D has, for example, five unit work stations #15 to #19, as shown in FIGS. 1 and 4, of which at least Each of the three work stations #16, #17, and #18 receives a rework instruction created based on defect data accumulated in each of the assembly work station group 1C (this creation is done by the distribution unit 53a, which will be described later). On the basis of the,
Controllers 70a to 70c for controlling the graphics display of the instructions, one CRT 7a, 7b, and 7c for displaying the graphics, and retightening of bolts based on the display contents of these CRTs 7a to 7c. For example, the first to third torque wrench units TWR1 to TWR, which are a set of three
3 is provided.

The CRTs 7a to 7c, for example, as shown in FIG. Messages, etc. are now displayed as defect information.

[0046] Codes LS1 to LS6 (Fig. 1, 12
Figure) are limit switches, respectively, and #15 above.
~ Work pallet 13, 13 to #19 station...
It is now possible to detect the import of At the repair work station, workers manually perform repairs, so it is necessary to detect the arrival of items in order to notify the workers.

These limit switches LS3 to LS
When each of 5 is turned ON, it indicates that a new vehicle body 6 has been delivered to the respective station.
Originally, when each limit switch LS3 to LS5 is turned on, the display CR of the corresponding rework work station is
It seems like it would be a good idea to switch the T's display screen to that of the new car. However, this switching is delayed in order to eliminate the inconvenience caused by the "chasing" described above (working based on the wrong screen). This point will be explained in detail later.

In this embodiment, for example, as shown in FIG.
A predetermined delay time tc is set from when each limit switch LS3 to LS5 is turned ON until the display screen of CRT7a to 7c is actually switched, while torque wrench units TWR1 to TWR are used when checking the work result.
Each input of WR3 is controlled so as to be in an insensitive state for a certain period of time ts after the delay time tc has elapsed. For example, in the case of the torque trench unit TWR1 of the #16 station, this control is performed as described above.
When #6 station or #17 station is within the above ts time, the torque wrench unit TWR1
It is controlled so that it becomes insensitive.

In FIG. 4, the three torque wrenches at each station are connected to each of the display management controllers 70a to 70c. This controller 70a-70
c is a failure data reading and distribution unit 53a, which will be described later.
Based on the information sent from , instructions for rework as shown in FIG. 5 are displayed. Further, encoders 75a to 75c connected to the display management controllers 70a to 70c of each rework work station detect the position of the pallet 13 carried into the rework work station. At each rework station,
The pallet 13 is the limit switch LS shown in FIG.
At the time each of 3 to LS5 is pressed, the encoder is initialized, and the amount of pallet movement from that time is detected by this encoder.

Auxiliary Work Station Group 1E The Auxiliary Work Station Group 1E is equipped with two unit work stations #20 and #21, for example, and performs work that exceeds that of the station group 1D on the vehicle body, such as tensioning the top sealing inside the vehicle interior. Perform final final assembly work assuming completion.

Lower part repair work station group 1F Furthermore, as shown in FIG.
It has two unit work stations. Station group 1
The operations at F are substantially similar to those for the rework station group 1D described above. That is, each station in this station group 1F has a CRT 7 for displaying malfunction information regarding the undercarriage, as shown in FIG.
d to 7g, and a set of four torque wrench units TWR4 to TW7 for repairing defective points. In addition, each work station #23 to #27
Limit switches LS9 to LS13 for detecting the loading of work pallets 13, 13, . . . to station group 1D are also provided in the same manner as in station group 1D. Furthermore, the CRT switching delay time tc and the torque wrench insensitive area ts are set in the lower rework work station group 1F, which is exactly the same as in the above-mentioned upper rework work station group 1D.

<Distributed management system for troubleshooting> The vehicle body transfer device 16, work pallet transfer device 17, docking device 40, slide device 45, and robots 48A and 48B of the assembly work station group 1C are all connected to the vehicle body 6 or the assembly work station group 1C. This is sequence control target equipment that executes predetermined sequence control in relation to parts 14 and 15.

In addition, the CRTs 7a to 7c of the work station group 1D for reworking the upper part of the car body and the CRTs 7d to 7g of the work station group 1F for reworking the lower part of the car body, including the surrounding auxiliary equipment, are used for display control for rework work. It can be thought of as a unit. As a result, assembly work station group 1C and rework work station group 1
Each subsystem of D and 1F can be represented by a system block as shown in FIGS. 7 and 8, for example. These systems shown in Figures 7 and 8 are
Configure an independent distributed management system for defect remediation.

That is, in the lower part repair system shown in FIG. 7, defects detected during the assembly process are written in the data carrier 60.
0 is read by the reading and distributing unit 53a of the #15 station, and this distributing unit 53a creates a rework work instruction indicating what kind of rework is to be performed at which rework work station, and distributes it to each rework work station. At each rework station, the rework control unit 54 displays the rework locations as shown in FIG. 5 in accordance with the distributed instructions. In FIG. 7, the rework control unit 54 (54a to 54c)
Display management controller 7 at each station in the figure
0, a torque wrench T, a CRT display device 7, an encoder, etc.

Regarding the repair of the upper part, as shown in FIG. This distribution unit 53b creates instructions as to which rework work should be performed at which station, and distributes the instructions to each station.

First, the assembly work station group 1C shown in FIG.
The combination of this and the lower section rework work station group 1F will be explained. As is clear from FIG. 1, in this embodiment, first, station # is used to perform subdivided individual unit operations such as assembling the engine 14, assembling the rear suspension 15, and assembling the fuel tank.
There are multiple sets (10 sets) of numbers 5 to #16. Therefore, they are the equipment 51a that is subject to multiple sets of sequence control.
~51j can be considered. Then, the plurality of sequence control target facilities 51a to 51j (in FIG. 7,
51a to 51f (not shown) are control/recording units 52a to 52j that respectively perform sequence control and record the work results in a data carrier 60 to be described later.
(52a to 52f are not shown) are provided correspondingly to each other.

Further, at work station #15, which is a bridging station between the assembly work station group 1C and the upper rework work station group 1D, the reading/distribution unit 53a is connected to the assembly work station group 1C.
Engine 14 and rear suspension 1 assembled in C
5 etc., and the read defect data is applied to each of the following 1st to 3rd unit work stations from #16 to #18 according to the workpiece and point of occurrence. It is distributed to rework control units 54a to 54c provided at the same time.

Control/recording units 52a to 52j control sequence work and record the work results.
and display control units 54a to 54c for rework are network interfaces 55 and 55, respectively.
. . , 57, 57 . . . are interconnected with the fault data reading and distributing unit 53 via data communication lines 56, 58.

Transfer of defect information data A data carrier 60 is fixed to the side of the work pallet 13 that moves along the vehicle production line and transports the vehicle body 6, as shown in FIG. Malfunction information is stored in this carrier 60. data carrier 6
0 includes a memory section 60b, a signal processing circuit section 60c, and a transmitting/receiving coil section 60a. This transmitting/receiving coil section 60a
The fault data supplied from the outside is stored in the memory 60b through electromagnetic inductive coupling between the control/recording unit 52n and an external coil (writing head 65 or reading head 64 of the control/recording unit 52n).
Alternatively, the data stored in the memory 60b can be optionally supplied to the outside (read/distribution unit 53a).

[0060] This data carrier 60 records and stores all data related to the pallet.
Information on the workpieces mounted on the pallet 13 has already been written before the workpieces are carried into the #31 station of the production line shown in the figure. The memory section 60b in the data carrier 60 has a total storage capacity of 6 to 8 KB, and its data structure is, for example, as shown in FIG. 11. That is, the storage area PD where production information data is stored
and storage areas SD1, SD2, SD3...SDn in which data regarding work results for each assembly work at each assembly work station are individually stored
It has two fields. Furthermore, storage areas SD1, S
For example, in the storage area SDm, each of D2, SD3, . and a field CDm for storing various other information regarding the occurrence of the malfunction (for example, a message regarding the malfunction). As described in connection with FIG. 5, using these data, the display management controller 70 displays the display shown in FIG. 5 on the CRT.

In this embodiment, microwaves using electromagnetic induction are used to transfer defect data because microwaves are relatively resistant to electromagnetic induction noise, and the data carrier 60 on the pallet side and the control/recording This is because the distance from the write head 65 of the unit 52 is long, and microwaves are suitable for long-distance data transfer. In addition, in a factory consisting only of lines that generate little dirt, the use of laser light may have the advantage of being more resistant to noise than the use of microwaves.

Furthermore, as shown in FIGS. 7 and 8, even though the stations are connected via communication lines, the data carrier 60 is used to transfer data. Since the data carrier 60 stores data unique to each pallet, it is more reliable to read/write information such as which station a particular pallet has arrived at than to manage it using a communication line. It is from.

As shown in FIG. 9, each of the control/recording units 52a to 52j (represented by 52n in FIG. 9) further includes a sequence control output section 61, a failure diagnosis recovery control section 62, and a data processing section. 63. The sequence control output section 61 supplies a sequence control signal to the sequence control target equipment 51n (51a to 51j are represented by 51n) on the work pallet 13 side. Failure diagnosis/
When a failure occurs in the sequence control target equipment 51n, the recovery control unit 62 detects the failure, specifies the location of the failure, and performs operational control to restore the equipment to a normal state. For example, if the object to be controlled by the sequence control unit 61 at a certain assembly station is a nut runner, if the nut runner detects an overload, it can be detected that a problem has occurred. The data processing unit 63 includes a sequence control output unit 61, a failure diagnosis/
It manages the recovery control section 62 and processes data sent and received via the network interface 55.

Further, the data processing section 63 includes a reading head section 64 having a built-in coil for reading data stored in the data carrier 60 fixed to the above-mentioned work pallet 13, and a coil for writing data to the carrier 60. The two heads of the write head unit 65 with built-in
They are connected via a write/read head control section 66. The write/read head control section 66 sets the write head section 65 in a write operation mode and writes the data sent from the data processing section 63 to the data carrier 60, or sets the read head 64 in a read operation mode. The data stored in the carrier 60 is supplied to the auxiliary work station group 1E as needed.

Read/Distribute Unit 53 FIG. 10 shows the configuration of the defective data read/distribute unit 53. As shown in FIG. 10, this unit 53 includes a read head section 64 for reading data stored in a data carrier 60 fixed to the work pallet 13.
It is connected to the distribution section 68. The data processing distribution section 68 is further connected to a network interface 55 and via a network 56 to each control/recording unit 52 of each assembly station.
In addition, as shown in FIG. 7, the rework unit 5 of each rework station is
4 is connected to the display management controller 70 of No. 4. The reading head control section 67 causes the reading head section 64 to assume a reading operation state and performs an operation of supplying the defect location data CP and defect data CD stored in the data carrier 60 to the data processing/distribution section 68. The data processing/distribution section 68 forms modified distribution data according to these data CP and CD, and sends it to the signal line 58.

The rework control unit 54 in FIG.
The overall configuration of a rework control unit 54 at a station where rework is performed is shown. The rework control unit 54 of each rework work station (stations #16 to #19, #23 to #27) includes a CRT 7,
The above-mentioned display management controller 70, encoder 75, a plurality of torque wrenches TWR, a lamp LA for informing the worker which torque wrench should be used, and a lamp LA for informing the worker which torque wrench should be used, and for indicating whether or not the torque wrench has been used by the worker. A hook switch LS for detection, a torque wrench controller 73 for controlling the torque wrench and detecting its load,
It consists of a network interface 57. Also,
The display management controller 70 includes a CRTC 74 that controls the display of the CRT display device 7 and a data processing section 71. The data processing unit 71 sends and receives data to and from the data communication line 58 via the network interface 57, inputs rework instructions, and creates a display screen for the instructions as shown in FIG. Send to CRTC74.

As mentioned above, the data processing section 71 is not only connected to the torque wrench controller 73, encoder 75, limit switch LS, and lamp LA, but also connected to the manual push button switch P that is pressed by the operator.
It is also connected to B. For this purpose, the data processing section 71
The encoder 75 allows the user to know the position of the pallet 13 that has entered the rework station, and the limit switch LS allows the user to determine whether the worker is actually using a torque wrench.
Based on the output of the torque wrench controller 73, it is possible to automatically determine whether the torque wrench has finished retightening the bolt. Although it is possible to automate the completion of rework work using a torque wrench in this way, automatic detection may not be possible depending on the work. For such rework work, the operator presses the button PB,
The data processing unit 71 is notified of the end of the work.

In FIG. 5, the symbols ``■'' to ``■'' mean the displayed work order. That is, the operator learns the procedure number from the display screen and performs the rework in that order. This order is sent from the distribution section 53 to the data processing section 71 via the communication line 58. The data processing unit 71 waits for the retightening end signal from the torque wrench controller 73 or for pressing the button PB in accordance with the order of (1) to (2) above. If, for example, the PB button is pressed while waiting for the rework work in the order of ■, the data processing unit 71 determines that the work in the order of ■ has been completed. If, for example, a retightening completion signal is sent from the torque wrench controller 73 while waiting for the retouching work in the order of ■, the data processing unit 71 determines that the work in the item (■) has been completed. do.

<Flow and Operation of the Entire System> Next, the flow and operation of this system will be explained. When a vehicle is finally assembled, first, the vehicle body 6 and the work pallet 13 on which various components to be assembled are placed are moved along the automobile assembly line section 1, and then assembled. The work stations are sequentially transported to each work station in the attached work station group 1C. The control/recording units 52a to 52j are the equipment 51a to 52j subject to sequence control.
51j. In this case, in each of the control/recording units 52a to 52j, the data processing section 63 controls the write/read head control section 6 as necessary.
6 to read the production information data stored in the data area PD corresponding to the assembly work station written in the data carrier 60. Then, the processing section 63 supplies control data based on the read production information data to the sequence control section 61. This sequence control unit 61 controls the sequence control target equipment 51.
A to 51j are made to take action according to control data from the data processing section 63.

The data processing section 63 further obtains data representing the results of the assembly work from the control section 61 and sends it to the failure diagnosis control section 62 to determine whether a malfunction has occurred. According to the determination result in the failure diagnosis control section 62, the head control section 66 is operated and the write head section 65 is activated.
The malfunction occurrence data of the data carrier 60 is written through the . This data is written in the field corresponding to the current assembly work in the storage areas SD1 to SDm corresponding to the assembly work station. That is, if the work result is appropriate, it is written to the storage area CC (see Figure 11) as work data, and if there is a problem with the work result, it is written to the workpiece where the problem occurred. , data regarding the position in the workpiece where the defect occurred is written to the storage area CP. Also,
A malfunction message regarding the malfunction at that time is written to the storage area CD.

In this way, in the assembly work station group 1C, the data carrier 60 of defect information
Data is written to the station sequentially.

#5 to #1 of assembly work station group 1C
The work pallet 13 (including the vehicle body 6 and various components assembled thereto) that has completed the assembly work at the work station No. 4 is transferred to the data reading station QS.
be moved to 1. Then, this work pallet 13 is first transferred to the data reading station QS1 (#15) as shown by the two-dot chain line in FIG.
station). Thereafter, the data processing/distributing section 68 (FIG. 10) of the fault data reading/distributing unit 53a disposed in the data reading station QS1 extracts the data from the data carrier 60 into storage areas SD1 to SDm corresponding to each assembly work station. Read the data. This allows the distribution unit 68 to know at which assembly station and at which position of which workpiece the defect has occurred.

[0073] The data processing/distribution unit 68 performs processing in order to eliminate these defects based on defect work data, defect points, defect content data, etc. of the vehicle placed on the pallet 13 read from the data carrier 60. The correction work to be performed is recognized and judged, and the content of the recognized correction work is sent to the correction work stations #16 and #17.
, #18, and sends corrected work distribution data for each work station representing this allocation to the data communication line 58 side.

In FIG. 13, it is assumed that the reading/distributing unit 53 reads defect data from 12 locations A to L from the carrier 60 for the vehicle 6 located at the #15 station. In the example of FIG. 13, the reading/distributing unit 53 is
Problems with A, B, and C are caused by D at station #16.
, E's fault is at #17 station, F's fault is at #17 station.
A defect and a station to fix it are assigned so that it is corrected at 18 stations. Such allocation information is inputted to the corresponding rework control units 54a to 54c of the first to third correction work stations #16, #17, and #18 via the network interface, where the information is specifically CRT7a for displaying defect data
7c.

Allocation and Distribution Method The method of distribution and allocation of rework work in the reading and distribution unit 53a will be explained with reference to FIGS. 15 and 16. As described in connection with FIG. 1, there are a wide variety of assembly operations performed at the assembly stations. Therefore,
Since the content of rework and the tools used for rework vary widely, rework should be performed at multiple stations.

[0076] The modification work for this system is as follows:
It is distributed based on the idea of ■. ■: Depending on the work content, it is classified into upper rework work and lower rework work, and these works are performed at station group 1D and 1F, respectively.
It is divided into two parts. This is because when assembling a car, it is more efficient to separate the work on the upper part and the work on the lower part. (2): Second, in addition to classifying the rework work into two types as described above, the distribution method of this embodiment also classifies the work by tool. ■: Third, it is generally possible to specialize a certain rework station to perform a particular rework operation. However, such specialization forces an increase in the number of rework stations. Furthermore, there may be cases where certain rework operations occur more frequently, while others occur less frequently. Therefore, the number and configuration of rework stations (assignment of what rework operations can be performed at which stations) should be determined by anticipating and taking into consideration the types and frequency of rework operations that may occur. ■: In a line for assembling engines, etc. to vehicle bodies, such as the example shown in Fig. 1, it is sufficient to classify the types of rework that occur at the assembly work station group 1C into lower and upper parts; It is sufficient to use three types of torque wrenches for rework at the upper part rework station group, and four types of torque wrenches are sufficient for rework at the 1st floor of the station group, which performs rework of the lower part. In view of this, #16~
All stations #19 are equipped with three types of torque wrenches (
T1, T2, T3 in Fig. 4), #23 to #2
All stations No. 7 have four types of torque wrenches (T1, T2, T3, and T4 in FIG. 6). In other words, all of the stations #16 to #19 can equally perform the rework of the upper part, and the stations #23 to #27 can also perform the rework of the lower part equally.

Therefore, for example, if it is necessary to rework 12 parts using torque wrench T2, use torque wrench T1 three times equally at each of the four stations #16 to #19. It is also possible for the distribution unit 53a to distribute so as to carry out rework operations. As for station #19, since this station is the last station to perform partial rework, the amount of work assigned to station #19 should be small in order to prevent unfinished rework. ■: Also, from the following viewpoint, rework work may be assigned to rework work stations. That is, rework work is assigned to rework work stations so that the movement of workers at each work station is minimized. In this case, if the torque wrench must be replaced, consideration should be given to the distance the operator will travel to replace the torque wrench. Furthermore, if it is possible to use the same torque wrench, multiple rework operations that are positionally close rework points should be assigned to the same rework work station.

In order for the distribution unit 53a to be able to allocate such rework work to rework stations, this unit 53a has a database as shown in FIGS. 15 and 16.

FIG. 15 shows a database set for each workpiece, and each record in this database is an identifier (WO
RKID), its location data (WORKPOS),
It consists of an identifier (TOOLID) of a rework tool that is required when a problem occurs in the work, and the time (TM) required to carry out the rework work. In other words, the 15th
One record in the diagram corresponds to one rework work.

FIG. 16 shows a database set for each rework station, which mainly describes tools that can be used at that station. Each record in this database includes the display switching delay time (tC) at the rework station, the period during which the detection of the end of rework is insensitive (tS), and the tool identifier (TOO) used for possible rework at that station.
LID).

The delay times tC and tS will be described later.

FIG. 17 is a flowchart showing the distribution algorithm in the distribution unit 53a. In step S2, when the arrival of a pallet is detected (this detection is done by limit switch LS2 in FIG. 4), the reading/distributing unit 53a sends the data carrier
Read the contents CC, CP, CD (Fig. 11) of 0. In step S6, this CD data and CP data are analyzed. In step S8, rework is distributed to each rework work station based on the analysis results.

The data processing in steps S6 and S8 will be explained in more detail. First, read the CD data, CP
Search the workpiece-tool database (Fig. 15) using the location of the data defect as a key, and search the data carrier 6.
For each defect occurrence position read from 0, the work identifier WORKID and work position WORK that match it.
Find one rework record with POS. WORKID, WORKPOS, which were found in this way,
All of the plurality of rework records consisting of a combination of tool identifier TOOLID and work time TM are sorted using TOOLID as a key. The set of records thus obtained is a set of data classified by tools required for rework work. Next, the sorted set of rework records is further categorized so that one worker can perform continuous rework using the same tool with as little travel distance as possible. In this case, W.O.
By referring to the RKPOS data, the moving distance of the rework worker is calculated and optimized so that the moving distance of the worker is minimized.

Assume that a set of rework records (RCD1, RCD2, RCD3, RCD4) obtained in this way is obtained for a certain tool (having an identifier TOOLID1) as shown in FIG. In the example shown in Figure 18, there are four rework operations (RCD1, RCD2, RCD3).
, RCD4) work time is TM1, TM2, TM3,
It becomes TM4. And if the total working time TM1+TM
2+TM3+TM4 exceeds the time required for the pallet to pass through its rework station, and if the total time TM1+TM2+TM3 does not exceed the time required for said pass, then
Rework work corresponding to D1, RCD2, and RCD3 is assigned to the rework work station. however,
When allocating rework work to a rework work station, the station database shown in FIG. 6 is searched using the TOOLID as a key to confirm that the tool is provided at the target station.

[0085] The rework work assigned to each station is assigned a work order so that the distance traveled is the shortest for each station. This optimization operation includes
Problem occurrence position data WORKPOS is used.

The rework instruction data thus distributed to each rework work station has a structure as shown in A in FIG. 19. In FIG. 19, the rework instruction data is classified for each workpiece in which a defect has occurred. A record for each workpiece is the position where the defect occurred (W
ORKPOS), the station number (ST#) in charge of correcting the defect, the identifier of the tool to be used for the correction (TOOLID), and a flag (FC) indicating whether or not the rework has been completed. .

The reading/distributing unit 53a passes the rework instruction data thus created to the rework work station via the data communication line 58, as shown in FIG.

<Operations at rework station>
Each rework work station, as shown in Figure 12,
It has a display controller 70 connected via a line 58 and an interface 57, a CRT display device 7, etc. Based on the rework instruction data obtained through the communication line 58, the controller 70 displays the rework work to be performed at this rework work station on the CRT display device 7. That is, the contents and objects of the reworking work to be performed on the vehicle body 6 and the various components assembled thereon at the reworking work station are displayed as shown in FIG. 5.

Referring to FIG. 5, a specific display mode of rework instructions will be explained. The content displayed on the CRT7 is
i. Indication of the commit number and vehicle type attached to the pallet; ii. Graphical display of the workpiece where the defect occurred and point display of the defect location, iii
．． modification order, iv. At least four types of message information are specifically displayed to convey more detailed information about the problem. The display mode of the defective position is, for example, (a) if there is a defect, the position is displayed with a red circle;
b) If there is a problem and the problem should be repaired at the relevant station, its location will be displayed with a double red circle. (c) If there is a problem but the repair has already been completed, the location will be displayed. (d) Not displayed if there are no defects.

[0090] Each rework work station includes, for example,
Each of the rework stations #16 to #18 has a
For example, as shown in Figure 4, three
Torque wrench units TWR1, TWR2, TWR3 equipped with one set of torque wrenches T1 to T3
is installed, and the torque wrench unit TWR1
~TWR3 are each display control controller 70
As shown in FIG. 12, they are electrically and mechanically linked.

Each of the torque wrenches T1 to T3 is adapted to be locked via a predetermined hook switch LST1 to LST3, and the corresponding indicator lamp LA1
~LA3 is provided, and by turning it ON or OFF, a specific instruction is given to the torque wrench as the tool to be used. And the display lamp LA1
~ LA3 When the corresponding torque wrench T1 ~ T3 is taken out and the repair work is done according to the display, the hook switches LST1 ~ LST3 will be turned OFF.
This allows the torque wrench T1 to T3 to be used correctly as instructed.
is confirmed to have been used. On the other hand, when the rework using the torque wrench is completed, the hook switches LST1 to LST3 are turned on, thereby detecting that the rework has been completed. All of these conditions are displayed on the CRT 7a for displaying defect data as described above.
-Displayed at 7c.

As described above, the end of the repair work using the torque wrench is determined by the controller 73 by detecting an increase in the load, and the controller 70 is notified of the end. Furthermore, for rework work for which automatic detection of completion is difficult, the operator notifies the controller 70 of this by pressing the button PB, as described above.

The rework instruction data explained in FIG. 19 is a rework instruction regarding a vehicle placed on a certain pallet 13. In this instruction data, the ST# field in FIG. 19 specifies which rework station each rework work should be performed at.

However, in actual work, even if there are 10 areas to be reworked at a certain station, the operator at that station may actually be able to complete only 8 areas. In such a case, the instruction data shown in FIG. 19 must be reconfigured. Therefore, in this system, when the pallet to be worked on there has advanced to a predetermined position, each rework work station transmits the instruction data (with the completion flag FC) shown in Fig. 19 to the work result data there. The data is then returned to the read/distribute station 53 as a result. The read/distribute station 53 receives this data and causes redistribution of rework work, if necessary. Step S1 to Step S1 in Fig. 17
8 shows the redistribution procedure.

If no new pallet has arrived at the reading/distributing station 53, the reading/distributing station 53 performs step S1.
0, waiting for the return of rework result data from the rework station. After receiving the resulting data,
In step S12, the sender is confirmed. This confirmation includes the commit number assigned to that palette and
This is done by comparing the result with the station number that returned the data. For example, #16, #17, #
18, #19, 13a, 13b, 1
This is because if pallets 3c and 13d exist, it is impossible for station #17 to send back the result data of pallet 13a, for example. After performing this verification, the process proceeds to step S14, where it is checked from the result data of the rework work whether there is any rework work that has not been completed at the sending station. If there is any unfinished work, proceed to step S16.
Then, the unfinished work is redistributed. This redistribution work can be performed using the same method as described in steps S4 and S6. That is, the tools required for the unfinished rework work are checked, the stations that have the tools are checked, and it is checked whether new rework work can be added to that station by reallocation. When new rework instruction data is created as a result of the redistribution, it is sent to the next station. In this way, the rework instruction data will be exceeded in the rework work station group.
Distribution unit 53a→#16 station→Distribution unit 53a→#17 station→Distribution unit 53a→
The route goes from #18 station to distribution unit 53a to #19 station.

Prevention of misidentification of rework position As described above, at each rework station, the screen (repair work instruction screen) is forcibly switched. This is because in assembly line work, it is possible for a worker to invade another worker's territory (so-called "chasing"), and this must be prevented. FIG. 20 explains how this forced screen switching can cause misunderstanding of the rework position.

In FIG. 20, pallets 13 and 13' are present at stations #16 and #17, respectively. and,
These pallets 13, 13' are shown moving along a line. At the time shown in FIG. 20(a), pallet 13' is still at station #16. At this point, rework instructions for the pallet 13 should be displayed on the CRT display device 7b of the #17 station. Thereafter, the line advances and reaches the state shown in FIG. 20(b), where the pallet 13'
arrives at station #17. However, in this system, the screen of the CRT 7b is not switched even at this point. This is because, at this point, the worker at station #17 is supposed to be reworking somewhere on the pallet 13. If the screen is changed immediately, the operator at station 17 will be able to
This is because there is a high possibility that a rework instruction for the pallet 13 will be mistaken for an instruction for the pallet 13. Furthermore, in this system, the display management controller automatically detects the end of rework, so the result of the rework performed by the worker on the vehicle on pallet 13 is stored as the result of work on the vehicle on pallet 13'. This is because

Therefore, in this system, (c
), that is, when time tC has elapsed since pallet 13' arrived at station #17, the screen is changed from one for pallet 13 to one for pallet 13'. This is because if the pallet 13' has progressed to this point, the operator will be able to fully understand the pallet itself. Therefore, at this point, a rework instruction for the pallet 13' is displayed on the CRT 7b.

FIG. 20(d) shows that after the time tS has elapsed, the pallet 13' has advanced to the time tC +tS. In this system, the time tS from the time point (c) to the time point (d) in FIG. Killing end signal detection. This is shown in Figure 20 (c
) and (d), if the worker continues the work without noticing the arrival of a new pallet, the end of the work will be treated as the end of work on pallet 13'. It will be remembered. In order to prevent such erroneous memory, if the termination signal is disabled, the problem will disappear. That is, by providing such a tS time period,
This is because, although there is a fear that a portion of the pallet 13 where the rework has actually been performed may be marked as unfinished, it is possible to reliably prevent a portion of the pallet 13 where the rework has not yet been completed from being recorded as completed.

FIG. 21 shows the control procedure of the display management controller 70 in the rework station. In step S20 in FIG. 21, it is checked whether an instruction for rework on the next pallet has arrived from the distribution unit 53, and if the instruction has arrived, the instruction data is stored in the area A in FIG. do. Area A is a storage area for instruction data for the next pallet, and area B in FIG. 20 is a storage area for instruction data for the pallet currently being reworked by the station.

[0101] The display management controller 70 is the encoder 7
5 (FIG. 12), and depending on the value, control is performed differently for steps S25 and below, for steps S30 and below, and for steps S40 and below. The encoder value becomes "0" when the next palette turns on the limit switch.

While the encoder output indicates that the time elapsed since the limit switch LS was turned on is less than tC, the display management controller 70 enables the detection of the completion signal in step S25, and confirms the completion of the rework in step S26. Then, in step S28, the flag FC corresponding to the part where the rework has been completed is set to "1", and as described above, the display of the part where the rework has been completed is changed to black. The operations in steps S26 to S28 are performed when a newly arrived pallet (palette 13 in the example of FIG.
), rather than the existing pallet (palette 13 in the example in Figure 20).
Revision work will be carried out on.

[0103] When the next pallet 13' advances to the TC position, in step S30, the controller 70
disables completion signal detection. Next, in step S32, the current palette (
The instruction data for the pallet 13) is distributed to the dispensing unit 53.
send it back to The instruction data returned to the unit 53 is
As described above (steps S10 to S20 in FIG. 17), the necessary rework will be redistributed and sent to the next rework.

[0104] The result data of the rework work is transferred to the controller 5.
3, if the display management controller 70 has received a rework instruction for the next pallet, it switches the screen in step S36.

Since the detection of the completion signal is disabled while a new pallet enters the territory of the station and is from the tC position to the tS position, the above-mentioned rework on the erroneous pallet is completed (Fig. 20). (Explained in connection with (d))) is prevented.

[0106] When a new pallet enters the area of the station concerned and further exceeds the tS position, the process proceeds to step S38.
Then, the detection of the completion signal is enabled, and the process proceeds to step S4.
0. At step S42, completion of the rework is detected, and the screen display is updated in response.

FIG. 22 is a detailed flowchart of the screen updating procedure in step S36. Step S5 in the same figure
0 resets the order counter to "1". This order counter is a counter that indicates the location where rework is currently being performed, and the value of the counter "1" corresponds to the rework order number "1" in FIG. 19. In step S52, the data in area A in FIG. 19 is moved to area B in order to switch the rework instruction from the old one to the new one. In step S54, screen display is performed based on this new instruction data.

FIG. 23 shows step S26 in FIG.
The detailed procedure for detecting the rework completion signal performed in step S40 will be described. That is, in step S60, it is checked whether a completion signal from the torque wrench controller 73 has been input. In step S62, it is checked whether button PB is pressed. If either one of the conditions is detected, a flag FC indicating that the repair work has been completed is set to "1" in step S64. At this time,
Flag FC is indexed by the order counter. In step S66, the order counter is incremented by one. In this way, as each modification work is completed, the corresponding flag FC becomes "1", and correspondingly, the screen on the CRT7 also changes to "1".
The corresponding location is displayed in black and the order counter is incremented.

Although the operations in the reading/distributing unit 53a and each station of the upper rework station group 1D have been mainly described above, the operations in the reading/distributing unit 53b and the lower rework station group 1F are also similar.

<Carrying out the assembled car body> On the other hand, once all the upper and lower parts of the vehicle have been assembled and the rework of the assembly parts has been completed, the assembled car body 6 will be removed.
The work pallet 13 that supported the is transferred to the #27 station, and its transfer and arrival are detected by the limit switch LS13.
, LS14 in a timely manner. and,
After proceeding to work station #28 and being placed on a lifter, it finally advances to work station #29,
Here, the assembled vehicle body is suspended from the hanger frame and is transferred in the direction of the arrow in FIG. 1 as directed by the assembled vehicle body return guide rail 3b of the previously extended vehicle body transfer line 3.

[0111] As a result, the work pallet 13 of the #29 work station becomes empty with no load on it. Therefore, the work pallet 13 is eventually transferred to work station #30 of the assembly parts sub-pallet loading station group 1H, where each of the front and rear sub-pallets 5a, 5b is pulled out laterally (to the upper side in FIG. 1), and At the side assembly parts mounting station group 1H, a front suspension and engine 14 are mounted on the front sub-pallet 5a, and a rear suspension 15 is mounted on the rear sub-pallet 5b. When the assembly parts such as the engine 14 and the suspension 15 have been installed, the work pallet 1 from which the sub-pallets 5a and 5b have been removed is
is waiting at the next #31 work station.
As with the waiting work pallet 1, the sub-pallets 5a and 5b each carrying the engine 14 and rear suspension 15 are fitted to the #4 station of the parts adjustment work station group 1B of #32 to #36. The assembly and rework operations described above are repeated. In this way, efficient automobile assembly work is carried out.

<Modifications> The present invention can be modified in various ways without departing from the spirit thereof. M-1: In the above embodiment, data exchange with the data carrier 60 was performed using microwaves, but data exchange using other media, such as a magnetic recording medium, or data exchange using a light beam is also possible. . M-2: In the above embodiment, the rework work at the rework work station was mainly performed using a torque wrench, but the present invention is of course applicable to rework work using other tools. Further, in the embodiment described above, the completion of the rework with the tool is automatically detected, but the completion of the rework of the throttle valve may be accompanied by a confirmation operation by the operator. In other words, the operator can confirm the completion of any rework work by pressing a predetermined button. M-3: In the above embodiment, the system automatically switches the instruction screen for rework work, but it may be changed so that the screen is switched by the operator's confirmation action. . M-4: In the above embodiment, the rework instruction data is
It was created in pallet units (see Figure 19). To this end, the instruction data was moved through each rework station with respect to the movement of the pallet. M-5: In the above embodiment, the work that can be performed at the rework station is mainly performed by workers, but the present invention is not limited thereto, and also includes repair work performed by automatic machines.

[0113] Therefore, the following modification is proposed. That is, the distribution unit 53 creates rework instruction data for one pallet for each station and distributes it to each station. Therefore,
At each station, rework work to be performed at that station is queued for each pallet.

[0114] In this case, the problem is to confirm that the rework work at each station has been completed. In a variant, this confirmation takes place in the distribution unit 53. Each station then sends a rework completion message via the communication line, as shown in FIGS. 24 and 25. 91a and 91b in FIGS. 24 and 25 indicate the transmission format.

[0115]

[Effects of the Invention] As explained above, according to the present invention,
It was possible to provide a production process management system that can accurately distribute correction work to a plurality of correction work stations according to the correction work.

[0116] Furthermore, in the case where a plurality of correction stations are provided on the correction line and correction work is distributed to these stations, if the correction work is not properly completed at any of the correction work stations, , it was possible to provide a production process control system that allows appropriate correction work to be executed at any subsequent correction work station.

[0117] Furthermore, it was possible to provide a production process management system in which correction work at the correction work station can be carried out efficiently.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram showing the overall system configuration of an automobile production line according to an embodiment of the present invention;

[Figure 2] A diagram showing a docking scene between a vehicle body and parts to be assembled at a station on the same production line.

[Figure 3] A plan view of the station in Figure 2;

[Figure 4] A block diagram showing the configuration of a station group that performs rework on the upper part.

FIG. 5 is a diagram showing the display mode of the display device 7 of the rework work station;

FIG. 6 is a block diagram showing the configuration of station group 1D for reworking the lower part;

FIG. 7 is a block diagram showing the relationship between a station group 1C that performs assembly work and a station group 1D that performs repair work on the lower part;

[Fig. 8] A block diagram showing the relationship with the station group 1F that performs rework work on the upper part;

FIG. 9 is a block diagram showing the configuration of a station for reworking the upper part or a station for reworking the lower part;

[Figure 10] A reader/reader that reads data indicating the occurrence of a defect and creates rework instruction data based on it.
A block diagram showing the configuration of the distribution unit 53,

[Figure 11]
A diagram showing the configuration of data stored in the data carrier 60,

FIG. 12 is a block diagram showing the configuration of a rework work station;

[Figure 13],

FIG. 14 is a diagram illustrating a method of distributing rework instruction data by the reading/distributing unit 53;

[Figure 15],

FIG. 16 is a diagram showing the structure of a database stored in the reading/distributing unit 53;

FIG. 17 is a flowchart showing the execution procedure in the reading/distributing unit 53;

FIG. 18 is a diagram illustrating a method of creating instruction data in the reading/distributing unit 53;

FIG. 19 is a diagram illustrating the structure of rework instruction data;

FIG. 20 is a diagram illustrating how so-called “chasing” occurs;

[Figure 21],

[Figure 22],

FIG. 23 is a flowchart illustrating the control procedure at the rework station;

[Figure 24],

FIG. 25 is a diagram illustrating a data transfer method in a modified example.

Claims (16)

[Claims] Claim 1: A production process system for managing a production process performed by a production line having a plurality of work stations that perform productive work on workpieces moving along the line, the system comprising: a production line consisting of a plurality of work stations for carrying out correction operations; a correction line connected in series to this production line and consisting of at least one correction station for carrying out correction operations; a plurality of work stations each having means for detecting a defect resulting from the productive work and writing the details of the defect to the data carrier, and the production line and the correction line. means for reading the contents of the data carrier provided between the data carriers; and based on the read contents, creating a modification instruction including information for specifying a correction part and information for specifying a tool to be used for the correction; A production process management system comprising: an instruction means for sending correction instructions to a correction station; and the correction station that performs correction work based on the correction instructions sent from the instruction station. 2. The production process management system according to claim 1, wherein the correction station includes display means for displaying the content of the correction. 3. The production process control system according to claim 1, wherein the correction tool is manually operated by an operator. 4. The production process control system according to claim 1, wherein the data carrier includes a microwave communication circuit, a circuit for writing data received from an external work station using microwaves into a RAM, and a circuit for writing data received from an external work station using microwaves into a RAM. and a circuit for reading the information and transmitting it to the reading means of the external instruction means through the microwave communication circuit. 5. The production process control system according to claim 1, wherein the work station includes a circuit for sending data to the data carrier using microwaves. 6. The production process control system according to claim 4, wherein the instruction means includes a circuit for receiving data from the data carrier using microwaves. 7. In claim 1, the modification line comprises a plurality of modification stations. 8. The production process control system according to claim 7, wherein the instructing means is set at one station between the production line and the correction line, and the instructing means is configured to identify the defective location and the necessary corrections. A first database storing correspondence with tools, a second database relating to tools equipped at the plurality of correction stations, and the first and second databases are searched, and the information is searched for each correction station. a search means for creating a combination of a defect to be corrected in the production process management system described in each correction station and a tool used therefor as the correction instruction; and a distribution means for distributing the correction instruction to each correction station via a communication line. Equipped with. 9. In the production process management system according to claim 7, each correction station is provided with display means for displaying the content of correction instructions directed to the correction station. 10. The production process control system according to claim 7, wherein the modification instruction includes information specifying a plurality of parts to be modified, information regarding a tool used for each modification, and information on each of the plurality of parts to be modified. and information regarding the order of correction operations. 11. The production process control system according to claim 7, wherein the instruction station sends a correction instruction to a correction station located next to the instruction station, and each correction station is configured to complete/complete an individual correction operation.
Detecting incomplete correction work, changing the unfinished correction work to a correction instruction to be performed at the next correction station, and transmitting this correction instruction to the next correction station using a communication line. send. 12. The production process control system according to claim 8, wherein the instruction station sends a correction instruction to a correction station located next to the instruction station, and each correction station determines whether the workpiece is under the jurisdiction of its station. The apparatus includes means for determining whether or not the range has been exceeded, and means for passing the correction instruction to the next correction station when the workpiece has passed the jurisdictional range. 13. The production process control system according to claim 12, wherein each correction station, when receiving the correction instruction from the previous correction station, displays the passed correction instruction for a predetermined period of time. The information is displayed on the display means with a delay. 14. The production process control system according to claim 12, wherein each correction station includes means for detecting completion/incompleteness of individual correction work at each station, and means for detecting completion/incompleteness of individual correction work at each station, and means for detecting completion/incompleteness of the correction work at each station, Means is provided for disabling said detection means for a predetermined period of time when delivered. 15. In the production process control system according to claim 1, the work at the correction station is performed manually. 16. A priority level determination unit that determines the priority level of the work to be performed for each work station, and a priority level determination unit that determines the priority level of the work to be performed based on the priority level data supplied from the priority level determination unit A work place display means for displaying a work place, a tool indicating means for instructing the storage position of a tool necessary for performing work at the work place displayed by the work place display means, and a tool instructed by the tool indicating means. a work completion detection means for detecting that the work has been completed; and a work completion detection means for instructing the next work part according to the priority level determined by the priority level determination section based on the detection result of the work completion detection means and proceeding with the work. A production process management system equipped with work process control means.