JP2000056810A - Control unit for production facility and its data managing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the control unit for production facilities which efficiently use the limited storage area of an ID tag and its data managing method. SOLUTION: The control unit which controls a work station when writing quality data to a free area in a quality data area of a memory provided to an ID tag writes a code representing 'quality data 4' representing quality data that its own station should write, the head address of the currently written quality data, and the number of the bytes of the data at the tail of the free area of the data management area and the quality data of its own station in order from the head address of the current free area of the quality data area.

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 facility and a data management method thereof.

[0002]

2. Description of the Related Art Conventionally, in a production facility for mass-producing industrial products, in particular, in a production facility such as an automobile for producing a plurality of types of products having different specifications on the same production line, individual works flowing through the production line are processed. To manage,
A work identification tag (ID tag) in which data such as specifications for each work is registered in advance is attached to each work.
A data management method of comparing data read from an ID tag with data obtained from a host computer when a work flows on a manufacturing line is employed. An example of such a technique is disclosed in
No. 341 and Japanese Patent Application Laid-Open No. 8-126494 by the present applicant.
No. has been proposed.

[0003]

Generally, a production line is provided with a plurality of work stations (hereinafter, "stations"), and work contents are different for each station. For this reason, data stored in the ID tag is often handled separately for each station.

FIG. 8 and FIG. 9 are diagrams showing a configuration of a memory map of an ID tag as a conventional example.

First, in the case of the example shown in FIG. 8, each data area is set to the same size in advance, and a control device such as a so-called PLC (programmable controller) for controlling each station refers to its own station. The data area to be registered is registered in advance. The control device of each station reads and writes data by directly referring to the data area for the own station. For this reason, for example, when a new station is added to the production line, it is necessary to read and write a data file relating to the new station as an additional file (additional file 4) in an empty area of the ID tag as shown in FIG. If the size of the additional file is larger than the size of the empty area set in the ID tag in advance, it cannot be handled.

Next, in the case of the example shown in FIG. 9, the data area in the ID tag is set efficiently without any spare area between the data areas. Therefore, the free area can be increased as compared with the case of FIG. 8, and this is an effective use method when handling a data file (file 4) relating to a new station. However, for example, when the configuration of the data (files 1 to 3) relating to the existing stations is changed, as described above, the control device of each station directly refers to the data area for its own station. Therefore, even if data for some stations is changed, it is necessary to re-register a new reference area for the own station in the control devices of all other stations, which is inefficient.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a control device for a production facility that efficiently uses a limited storage area of an ID tag and a data management method for the control device.

[0008]

In order to achieve the above object, a production equipment control device according to the present invention has the following configuration.

That is, a control device for accessing an ID tag capable of storing work identification data and data relating to the work and controlling a production facility, wherein a data area, a data area and a data area are stored in an address space having a predetermined storage capacity. Access means for reading / writing data from / to an ID tag having a storage area in the order of the management area; and writing new data to the empty area of the data area with the MSB justified and identifying the identification number of the written new data. And data writing means for writing data indicating the position, the size, and the size in the free space of the data management area in a left-justified manner.

Preferably, the position and the size of the data to be read are detected from the data management area based on the data representing the identification number, and the data and the position and the size written together with the detected identification number are written. And data reading means for reading data from the data area.

For example, when the data written in the data area can be deleted, the data indicating the identification number of the data written in the data management area is replaced with a predetermined data indicating that the data can be deleted. Further comprising data deletion means for changing to data, wherein the data writing means searches for the presence of the predetermined data in the data management area when writing new data to the data area, and as a result of the search When the predetermined data exists, the size written together with the predetermined data is compared with the size of the new data. When the size of the new data is larger, the new data is stored in the data area. If the size of the new data is smaller than that of the new data, it is written in the empty area with the left justified. The position of the data area indicated by being written position, may write the new data.

Further, in order to achieve the above object, a data management method according to the present invention has the following configuration.

That is, a data management method in a control device for controlling a production facility while accessing an ID tag capable of storing identification data of a work and data relating to the work, wherein the method includes the steps of: When data is read / written from / to an ID tag having a storage area in the order of a data area and a data management area, new data is written to an empty area of the data area with the MSB justified, and the written new data is Data representing the identification number, position, and size
The method further comprises a data writing step of writing the data in the free space of the data management area with the left justification.

Preferably, a detecting step of detecting a position and a size of data to be read based on data representing an identification number from the data management area, and a position and a size written together with the detected identification number are determined. Reading a data from the data area in accordance with the data to be represented.

[0015]

An embodiment of the present invention will be described below in detail with reference to the drawings. In the present embodiment, for example, the control device for production equipment according to the present invention is applied to a system for performing a work instruction and a quality control in each station (STN) based on data of an ID tag attached to an automobile as a work. Will be explained.

First, the overall configuration and operation of the system according to the present embodiment will be described with reference to FIGS.

FIG. 1 is a block diagram showing a system configuration of a production equipment control device according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a control device such as a so-called PLC (programmable controller) for controlling each station. Reference numeral 2 denotes a host computer which is an external device. Reference numeral 10 denotes an ID tag attached to an automobile, which is a work (not shown). In the ID tag 10,
A memory is provided as a general readable / writable storage medium. As shown in FIG. 1, a work data area, a quality data area, and a data management area are set in predetermined memory areas, respectively (details will be described later). Do).
An ID tag reader / writer 28 is connected to the control device 1. The control device can read and write data stored in the ID tag 10 via the ID tag reader / writer 28.

Here, the configuration of the ID tag 10 and the ID tag reader / writer 28 may be any of a non-contact type and a contact type. It is only necessary to adopt a general unit that includes a unit and can perform mutual communication.

FIG. 2 is a block diagram of a control device according to an embodiment of the present invention.

In the figure, reference numeral 24 denotes a ROM that stores a boot program and the like. Reference numeral 25 denotes a RAM for temporarily storing various processing results, a program for realizing a data management process described later, and the like. The RAM 25 stores a program for realizing a work instruction and / or quality assurance according to the use of the control device. Reference numeral 26 denotes an input / output interface for converting input / output signals from a processing device, a switch, and the like (not shown) provided in the station. 27
Is a communication interface for communicating with an external device via the communication line 30. And 28 is the I
It is a D tag reader / writer. These components are connected via an internal bus 29, and the CPU 21
In accordance with the program stored in the control device 25, the control device 1 is entirely controlled.

The control device 1 is not limited to a PLC, but may be a personal computer (PC) as long as the input / output interface 26 can be connected.

Next, the overall operation of the system of FIG. 1 having such a configuration will be described.

Work data relating to work instructions to be performed at a plurality of stations of the production facility is downloaded from the host computer 2 to the master station. The control device 1 of the master station writes the work data corresponding to the work to which the ID tag is attached to the work data area of the ID tag 10 by the function of the program of the work instruction system. Here, the work data includes data representing a work instruction for each subsequent station.

When the control device 1 of the station downstream of the master station detects a work flowing on the production line by a general method, the control device 1 of the ID tag reader / controller 1 detects the work.
Via the writer 28, the work data for the own station is read from the work data area of the ID tag 10 by the method described later,
The operator is instructed according to the contents of the read data. Further, when the worker completes the work, the quality data of the work at that time is written into the quality data area of the ID tag of the work by a method described later by the function of the program of the quality management system. The work for which the processing up to this point has been completed moves to the next station.

In the control device 1 of the inspection station, which is the final step shown in FIG. 2, all data stored in the quality data area of the ID tag 10 is read out via the ID tag reader / writer 28, and the read out data is read out. The data is used to perform quality control and inspection processing on whether or not a predetermined work set in advance by the host computer 2 has been performed on the work, and the results of the processing are taken as quality information on the work by the host computer 2. Send to A work in which any abnormality is detected in the inspection station is sent to a repair process.

<Data Management Processing> Next, data management processing performed by the control device 1 will be described.

FIG. 3 shows an ID according to an embodiment of the present invention.
FIG. 9 is a diagram illustrating a part of a memory map of a tag, and illustrates a case where data is written in a free area. FIG. 4 is a flowchart illustrating a process when the control device writes data to the ID tag according to the embodiment of the present invention.

In the present embodiment, the ID tag 10 includes a work data area, a quality data area,
The data area is divided into three data management areas in advance. FIG. 3 shows a quality data area and a data management area among these three areas for convenience of explanation.

As shown in FIG. 3, in the data management area, a tag name (quality data in FIG. 3) indicating the type of data, a head address of a storage destination of the data, and the number of bytes indicating the size of the data are specified. Is stored as capacity data.

Therefore, in the present embodiment, the control device 1
When writing the quality data in the ID tag 10, a search is made for a free area in the quality data area (step S1).
The size of the empty area is compared with the size of the quality data to be written this time (step S2).

If the result of the determination in steps S2 and S3 is YES (when it is determined that the quality data can be written), in steps S4 and S5, the last of the free space in the data management area is determined. At the end, a code indicating "quality data 4" indicating the quality data to be written by the own station, the start address of the quality data to be written this time, and the number of bytes of the data are written (step S4), and the current free area of the quality data area is written. The quality data in the own station is written in order from the head address of (step S5).

When the determination in step S2 is NO (when there is no free area) or when the determination in step S3 is NG (when it is determined that the data size of the free area is small), for example, the line Predetermined error processing such as stop is performed in step S6.

As described above, according to the data management processing of FIG. 4 described above, when writing the quality data into the ID tag 10, the data area is used left justified and the data management area is used left justified. The limited storage area of the tag 10 can be used efficiently.

Although not shown in FIG. 3, the control device 1
When the work data is read from the ID tag 10, first, the tag name in the data management area is searched for a code representing the work data to be read by the own station. When the code is found, the code corresponding to the tag name is searched. The head address and the number of bytes of the work data are read, and the data of the area corresponding to the read data may be read as the work data of the own station this time.

In the present embodiment, the control device 1
The data in the ID tag 10 can be deleted. For example, in FIG. 5, when deleting the quality data 2,
The tag name in which the quality data 2 in the data management area is set is changed to predetermined data (hereinafter, deleted data) indicating that the quality data area has an area (deletion area) in which data rewriting is permitted. At this time, in order to make it possible to identify the location and size of the deletion area in the subsequent processing, the data indicating the head address and the number of bytes corresponding to the tag name changed to the deletion data is held as it is. In the data management process of FIG. 4 described above, when the quality data in the own station is larger than the data size of the free area, the error processing is performed in step S6, but when there is a deletion area, the processing described below is performed. May be.

FIG. 6 is a diagram showing an ID according to an embodiment of the present invention.
It is a figure which shows a part of memory map of a tag, and shows the case where data is written to a deletion area or a free area.
FIG. 7 is a diagram illustrating an example of the operation of the control device according to the embodiment of the present invention.
It is a flowchart which shows the process at the time of writing data to a D tag.

FIG. 6 shows an example in which the quality data 4 is written into the ID tag 10. In this case, the control device 1 handling the quality data 4 determines whether the deletion area or the deletion area is to be written according to the number of bytes of the quality data to be written this time. The data is written at the start address of the free area.

That is, the control device 1 searches the tag name of the entire data management area (step S11), and determines whether or not there is deletion data indicating that there is a deletion area in the quality data area (step S12). Step S12
When YES (when it is determined that there is deleted data)
In step S13, the number of bytes representing the size of the deletion area corresponding to the tag name storing the deletion data is compared with the number of bytes of the quality data to be written this time.

If it is determined in step S13 that the number of bytes of the quality data is equal to or less than the number of bytes of the deletion area, in steps S14 and S15, the tag name of the data management area where the currently deleted data is stored is The own station writes a code indicating "quality data 4" indicating the quality data to be written (step S14), and writes the quality data to be written this time into the area which is the currently deleted area (step S15).

If the determination in step S12 is NO (there is no deletion area), or if the determination in step S13 determines that the data size of the deletion area is small, the end of the quality data area is searched ( Step S1
6) The quality data in the own station is written in order with the searched last address as the first address (step S17), and the "quality data 4" representing the quality data written by the own station at the last of the free area of the data management area. , The head address of the currently written quality data, and the number of bytes of the data are written (step S18).

As described above, if such data management processing is performed in each control device 1, data access independent of the size of data to be handled is realized, and
The limited storage area of the ID tag 10 can be used efficiently. As a result, it is possible to quickly respond to a change such as addition or abolition of a station in the production line.

In the above-described embodiment, the case where the memory area of the ID tag 10 has the data area and the data management area in the memory has been described as an example. The data area was left justified and the data management area was left justified. Therefore, when a storage area is provided in the order of the data management area and the data area, it goes without saying that the writing method may be reversed.

[0044]

As described above, according to the present invention,
A control device for a production facility that efficiently uses a limited storage area of an ID tag and a data management method thereof are provided.

That is, according to the first and sixth aspects of the present invention, data can be efficiently written in the limited storage area of the ID tag.

According to the second and seventh aspects of the present invention, desired data can be quickly read out of the data written in the limited data area of the ID tag with high efficiency.

According to the third aspect of the present invention, when a part of the data written in the data area of the ID tag becomes unnecessary, the unnecessary area is diverted for writing new data. Therefore, the number of machines that use the empty area of the data area can be reduced, and the limited data area of the ID tag can be used efficiently.

[0048]

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a system configuration configured by a control device of a production facility as one embodiment of the present invention.

FIG. 2 is a block configuration diagram of a control device as one embodiment of the present invention.

FIG. 3 is a diagram showing a part of a memory map of an ID tag according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating an example of an I by a control device according to an embodiment of the present invention.
It is a flowchart which shows the process at the time of writing data to a D tag.

FIG. 5 is a diagram illustrating a case where a deletion area is set in a data area of an ID tag.

FIG. 6 is a diagram illustrating a part of a memory map of an ID tag according to an embodiment of the present invention.

FIG. 7 is a diagram showing an example of an I by a control device according to an embodiment of the present invention.
It is a flowchart which shows the process at the time of writing data to a D tag.

FIG. 8 is a diagram showing a configuration of a memory map of an ID tag as a conventional example.

FIG. 9 is a diagram showing a configuration of a memory map of an ID tag as a conventional example.

[Explanation of symbols]

 1: control device, 2: host computer, 10: ID tag, 21: CPU, 24: ROM, 25: RAM, 26: input / output interface, 27: communication interface, 28: ID tag reader / writer, 29: internal bus, 30: communication line,

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tatsuro Morimoto 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. (72) Inventor Yutaka Naito 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. Inside

Claims (7)

[Claims] 1. A control device for accessing an ID tag capable of storing identification data of a work and data relating to the work and controlling a production facility, wherein a data area, a data area, and a data area are stored in an address space having a predetermined storage capacity. Access means for reading / writing data from / to an ID tag having a storage area in the order of the management area; and writing new data to the empty area of the data area with the MSB justified and identifying the identification number of the written new data. And a data writing unit for writing data representing the position, size, and size in the free space of the data management area, in a left-justified manner. 2. A position and a size of data to be read are detected based on data representing an identification number from the data management area, and according to data representing a position and a size written together with the detected identification number. 2. The control device according to claim 1, further comprising data reading means for reading data from said data area. 3. When data written in the data area becomes erasable, data representing the identification number of the data written in the data management area is replaced with predetermined data representing erasability. The data writing unit further includes a data deletion unit for changing, when writing new data in the data area, searches for whether the predetermined data exists in the data management area, and as a result of the search,
When the predetermined data exists, the size written together with the predetermined data is compared with the size of the new data. When the size of the new data is larger, the new data is stored in the free space of the data area. 2. The method according to claim 1, wherein the new data is written in an area in the data area indicated by a position where the new data is written together with the predetermined data when the size of the new data is smaller. Or the control device according to claim 2. 4. The control device according to claim 1, wherein the data read by the data reading means from the ID tag is work instruction data at a work station controlled by the control device. 5. The control device according to claim 1, wherein the new data written by the data writing means to the ID tag is quality data of a work in a work station controlled by the control device. . 6. A data management method in a control device that accesses an ID tag capable of storing identification data of a work and data relating to the work, and controls a production facility, comprising: an address space having a predetermined storage capacity; When reading / writing data from / to an ID tag having a storage area in the order of a data area and a data management area, new data is written to the empty area of the data area with the MSB justified, and the written new data is A data management method, comprising: a data writing step of writing data representing an identification number, a position, and a size into a free area of the data management area in a left-justified manner. 7. A detecting step of detecting a position and a size of data to be read based on data representing an identification number from the data management area, and indicating a position and a size written together with the detected identification number. 7. The data management method according to claim 6, further comprising a data reading step of reading data from the data area according to the data.