JP3455196B2 - Control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention
Control means such as a logic controller (hereinafter abbreviated as PLC) and display means for displaying the control state of the control means are constituted as a set of control devices, and the control devices are connected by a plurality of sets of network lines. The present invention relates to a control device controlled by a host device such as one or a plurality of host computers. FIG. 3 is a block diagram showing a schematic configuration of a typical prior art control device. As described above, a plurality of n PLCs t1, t2,..., Tn (hereinafter, collectively referred to by a reference numeral t) are dedicated display devices p1, p2,. p), and is connected to a host computer 2 via a network line 1. PLC
In response to a control output from the host computer 2, t controls one or a plurality of control target devices (not shown), receives states of the control target devices from a sensor (not shown), and displays the corresponding display device p. To be displayed. [0003] The PLCt may use a different protocol for communication for each manufacturer, or even for the same manufacturer, depending on the case. Therefore, a control device such as that shown in FIG. 3 can form a network only when the PLCt protocols are equal to each other or are compatible products of the same manufacturer, and in some cases the versions are close to each other. In order for a PLC made by another company to participate in the network line 1 as indicated by t0, a protocol converter 3 needs to be interposed on the way. A dedicated display device p0 is connected to PLCt0. [0004] Therefore, there is a problem that a very large network cannot be constructed, and a control program must be prepared for each network, that is, for each protocol. For this reason, the present applicant has previously proposed a completely new control device in Japanese Patent Application No. 10-117117. FIG. 4 shows the configuration of the control device. In the control device shown in FIG. 4, the manufacturers and versions are different from each other, and PLCa1, b1, and c1 having their own protocols a, b, and c are transmitted via display devices a2, b2, and c2. Network line 1
It is connected to the. The network line 1 is, for example, T
Communication is performed using a general-purpose protocol d such as CP / IP. Therefore, each display device a2, b2, c
2 has a function of converting protocols a, b, and c specific to the corresponding PLCa1, b1, and c1 and a common protocol d. That is, these are PLCa1, b1, c1
Is originally developed from a control sequencer using a relay, and has a switch ON / OFF control,
Although it is excellent in the function as an input / output circuit such as data acquisition from a sensor, it is inferior in the data communication function. On the other hand, the display devices a2, b2, and c2 have been developed as personal computer application devices. Therefore, communication with a general-purpose personal computer can be easily performed by a general-purpose protocol d, and the corresponding PLCa1, b1, c
This is because the dedicated protocols a, b, and c have been developed for 1 respectively. [0007] The control device having the above-described configuration is configured to display the display devices a2, b2, and c2 that handle relatively large-capacity image data, and the P-device that handles relatively small-capacity data.
By interposing between the LCa1, b1, c1 and the network line 1, each host computer 2
Control output to Ca1, b1, c1 and PLCa1, b
1, c1 to the host computer 2 through the display devices a2, b2, and c2.
Each can be transmitted without any trouble,
A novel control in which protocol conversion is performed using the high arithmetic processing capability of the display devices a2, b2, and c2, and the host computer 2 can control each PLCa1, b1, and c1 with a common program. Device. Thus, various PLCs having different protocols can be used without using the protocol converter 3 or the like.
Can be connected to the network line 1, the system can be easily expanded or changed, and the number of steps for creating a program can be greatly simplified. However, the control device shown in FIG. 3 understands a unique protocol or command, brings a personal computer to the manufacturing site, and directly controls the PLCt.
Without the connection to, the data and programs could not be stolen or tampered with, whereas the control device shown in FIG. 4 facilitated the construction of a large-scale general-purpose network by the shared protocol d. In addition, the connection to the network line 1 is facilitated, and important programs such as application programs in which the know-how of the user is condensed by access from other manufacturing lines, other departments in the company, and from outside the company. There is a problem that data is destroyed or human life is threatened by a malfunction of a machine tool due to falsification of data. An object of the present invention is to provide a control device capable of improving the security of data and programs. [0011] A control device according to the present invention relates to a plurality of control means and control of the control means from the control means.
Display means for displaying information
A control device comprising:
At least some of the columns have unique and unique processes.
Protocol, and the plurality of control means
Connected to the network line via corresponding display means.
Are, Table <br/> Display means interposed between said control means and host system, it has rows conversion between common protocols and proprietary protocol of the control unit side of the network line side, the Ne
Shared program from host device via network line
The control output by the system is transmitted to the control means, and the control output
Control means in response to a force due to controlling the control object
And the control means is controlled by the host device by the sharing program.
And a password of a plurality of predetermined levels is set and registered for each of the display means, distributed to a required display means at a predetermined rewriting timing via the network line, and input from a higher-level device. The transmitted password is transmitted to the display means, and the transmitted password is compared with a pre-registered password in the display means, and the operation from the host device to each display means is performed in accordance with the password. Thus, it is characterized in that the limitation is performed for each of the layers. According to the above arrangement, the display means corresponding to the control means and handling relatively large-volume image data is compared with the control means handling relatively small-capacity data such as ON / OFF data. Utilizing the high arithmetic processing capability, a control means having a specific protocol is connected to a general-purpose protocol network line such as TCP / IP via this display means, and a host device such as a host computer or the like is connected. A large-scale control device capable of easily performing expansion and modification with improved versatility in which protocol conversion of data and programs to be transmitted between other control means and the corresponding display means is performed. Among other computers to be connected by the general-purpose networking, undesired signals from the computer whose password does not match, etc. In the display device side, it is screened by a password. Therefore, it is possible to prevent data and programs from being undesirably rewritten. Further, since the password has a hierarchical structure, the data and the program can be changed according to the hierarchy of the operator who can know the password, and thus the security of the data and the program is improved. be able to. BEST MODE FOR CARRYING OUT THE INVENTION
The following is a description based on FIG. 1 and FIG. FIG. 1 is a block diagram showing a functional configuration of a control device according to an embodiment of the present invention. PLCA1, B
Reference numerals 1 and 1 control a device to be controlled 12 such as a motor or a solenoid valve in response to a control output from a host computer 11. PLCA1, B1 and C1 are sensors 13
The control state of the control target device 12 is detected by, for example, and the detection result is transmitted to the host computer 11 or another display device, and used for display, calculation of the control output, and further analysis, and the like. Display A
Images are displayed in 2, 2, and C2. In this way, the control device controls a machine tool, a production line, and the like. Note that in the example of FIG.
1, B1, C1 are provided, but one,
Needless to say, two or four or more host computers 11 may be provided. In the example of FIG. 1, the control target device 12 and the sensor 13 are PLCB1 and C
1 is omitted. The PLCAs 1, B1, C1 and the corresponding display devices A2, B2, C2 are connected by connection cables A3, B3, C3, respectively, and the manufacturers of the PLCAs 1, B1, C1 and Exclusive protocols A, B,
C performs data communication. Display A
2, B2, and C2 have been developed as personal computer application devices. It is essential that a general-purpose personal computer can easily communicate with a general-purpose protocol D and be connected to the general-purpose personal computer. Dedicated protocols A, B, and C have been developed for the corresponding PLCAs 1, B1, and C1, respectively. Therefore, the display devices A2, B2, C2
Are the PLCAs 1, B1, and C1 and the host computer 11
And the display devices A2, B2, C2
Is connected to the host computer 11 via a network line 14 such as Ethernet (registered trademark), and a common protocol, for example, a protocol on TCP / IP, as indicated by reference numeral D, is used for the protocol. The display devices A2, B2, and C2 perform protocol conversion between the protocol D and the protocols A, B, and C, respectively. Thus, a large-scale network line 14 is constructed by the common protocol D. An external host 15 installed at a remote location such as a manufacturer of the display devices A2, B2, and C2 can be connected to the network line 14 via a router and a public telephone line for maintenance. Therefore, personal computers inside and outside the company can be connected. For this reason, according to the present invention, each of the display devices A2,
A password composed of a plurality of layers is set for each of B2 and C2. In the host computer 11, the setting means 2
1, node information indicating which type of display device is connected to which node, and each P
A network file 22 including symbol names of control target devices and sensors connected to the LCAs 1, B1, and C1 is created in advance, and the application unit 23 refers to the network file 22 via the interface circuit 24 to refer to the network file 22. The control output to each of the PLCAs 1, B1, and C1 is distributed, control in response to the control output is performed on the control target device 12, and data representing a control state such as a detection result of the sensor 13 is transmitted to the interface. The information is returned to the application unit 23 via the circuit 24, and is used for calculation and analysis of the display and control output. In the host computer 11, passwords in the display devices A2, B2, and C2 and conversion data between the protocols A, B, and C and the protocol D are registered in the data file 25 in advance. The password is transferred to a required display device at a predetermined rewriting timing such as during maintenance or the like by an interface circuit 2.
4, the converted data is transmitted to an interface circuit 24 to a required display device at the time of maintenance such as a change of a PLC connected to the network line 14.
Will be delivered via Correspondingly, each of the display devices A2, B2,
C2 is an interface circuit 26 and an image memory 27
, A protocol conversion circuit 28, a display panel 29, an input unit 30, and a password matching unit 31. The interface circuit 26 and the protocol conversion circuit 28 perform two-way communication with the host computer 11 and with the PLCAs 1, B1, and C1.
Configuring a driver and using protocol conversion data given from the data file 25 in real time,
Performs protocol conversion of input / output data. Such a protocol conversion is performed by using the protocol D common on the network line 14 and each PLCA.
1, B1, and C1 by using a conversion table and a conversion function between the protocols A, B, and C unique to each other.
These tables and functions are stored in the data file 25 in advance, and are selected at the time of creating the network file 22 in which model setting of the display devices A2, B2, and C2 connected to each node as described above is performed. , Are set in the protocol conversion circuit 28. In the image memory 27, invariant characters and image data including the names and units of the respective controlled devices are stored in advance on a background screen imitating a production line, for example. The variable data indicating the control state input from the protocol conversion circuit 28 is synthesized and displayed on the display panel 29 as an image. The display devices A2, B2, and C2 display the corresponding P
Together with the LCAs 1, B1, and C1, they are integrated into an operation console or the like of a production line or are independently disposed, and are used as a control panel or the like. On the front side of the display panel 29,
An input means 30 such as a touch panel is provided, and in response to the input result, data input or the control target device 1 is performed.
Two indirect controls can be performed. Display device A2
B2 and C2 are configured almost in the same way as a general-purpose personal computer, and include a central processing unit, a memory such as a ROM or a RAM, an external storage device such as a hard disk device, a graphic controller and a communication device via an internal bus line. Controllers and the like are connected to each other. FIG. 2 is a diagram for explaining the hierarchical structure of the password. As shown in FIG. 2, a password is set in accordance with the level of the operator, and each of the display devices A2, B2, and C2 allows operation at the level corresponding to the password. That is, the password is entered in the input means 2
It is input from 0 and transmitted to each of the display devices A2, B2, C2 at the time of login, which is the start of a series of operations. In each of the display devices A2, B2, and C2, the transmitted password is compared with a pre-registered password in the password matching means 31, and the password, and therefore the level of the operator, is determined for the subsequent input operation. Up to the operation corresponding to. Once the user is logged off and a series of operations is completed, the password is collated again at the next login. The collation of the password is not limited to the above-described login, and may be performed for each command when, for example, importance is placed on security. In the example shown in FIG. 2, a person in charge of the manufacturing site or an administrator such as a programmer of a manufacturer of the display devices A2, B2, and C2 performs all input operations such as changing passwords and manufacturing procedures. The operator at the actual manufacturing site can write data such as dimensional data, and other departments in the company can read data such as the number of products manufactured. From outside the company,
Indicates that no operation can be performed at all. As described above, in the control device according to the present invention,
The display devices A2, B2, and C2 having high arithmetic processing capabilities and high suitability for data communication are represented by PLCA1, B1, and C1.
And the host computer 11 or the external host 15, and sends control output from the host computer 11 and control state data from the PLCAs 1, B 1, and C 1 to the PLCs 1, B 1, and C 1 and the host computer 11, respectively. It is possible to convert the protocol and transmit it, and to standardize the protocol D to make the network circuit 14 large-scale and easy to connect from other network circuits. Furthermore, even when a computer or the like outside the company can be connected, the display devices A2, B2, and C2 display the password set in the accessing computer, that is, the input operation up to the level corresponding to the level of the operator of the computer. Only the user's know-how is condensed The no longer be important programs and data such as an application program is destroyed, it is possible to improve the security of the data and programs. As described above, in the control device according to the present invention, the display means interposed between the control means and the higher-level device includes:
Common protocol on network line side and each control means side
The conversion to and from the specific protocol of the network
Control by a shared program from a higher-level device via a line
Control output to the control means, and responds to the control output.
The control means controls the control object to
The shared device controls a plurality of control means that use different protocols among at least some of the control means in the sharing program. A control device capable of performing a large-scale general-purpose operation by distributing a registered password to a display means that requires the password, and comparing the password input from the higher-level device with the registered password on the display means. Among other computers to be connected by networking, an undesired signal from a higher-level device (computer or the like) whose password does not match is selected on the display means side. Therefore, it is possible to prevent data and programs from being undesirably rewritten. Further, since the password has a hierarchical structure, the data and the program can be changed according to the hierarchy of the operator who can know the password, and thus the security of the data and the program is improved. be able to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a functional configuration of a control device according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a hierarchical structure of a password used in the control device shown in FIG. FIG. 3 is a block diagram showing a schematic configuration of a typical prior art control device. FIG. 4 is a block diagram showing a schematic configuration of another conventional control device. [Description of Signs] 11 Host computer (host device) 12 Device to be controlled (target to be controlled) 13 Sensor 14 Network line 15 External host (host device) 20, 30 Input means 21 Setting means 22 Network file 23 Application part 24, 26 Interface Face circuit 25 Data file 27 Image memory 28 Protocol conversion circuit 29 Display panel 31 Password verification means A, B, C, D Protocols A1, B1, C1 PLC (control means) A2, B2, C2 Display device (display means) A3 B3, C3 connection cable

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-304695 (JP, A) JP-A-1-152830 (JP, A) JP-A-4-160666 (JP, A) 27942 (JP, U) Seiji Takeda, Trends of Latest Panel Computers and Their Applications, Japan, Nikkan Kogyo Shimbun, November 1996, Vol. 41, No. 11, p. 47-53 (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 29/06 H04L 9/32 G06F 13/00

Claims (1)

(57) [Claims] [Claim 1] A plurality of control means and their control from the control means
Display means and network line for displaying information related to
And a higher-level device connected to the control device, wherein at least a part of the control means differs from each other.
A unique protocol is used, and the plurality of control means are connected via corresponding display means.
And is connected to said network line, the tables indicate means interposed between said control means and higher-
There line conversion between common protocols and proprietary protocol of the control unit side of the network line side, the network
Control by a shared program from a higher-level device via a line
It transmits the control output to said control means, by the control means in response to the control output for controlling the controlled object, the upper
Device controls each control means by the sharing program
At the same time, a password of a predetermined plurality of levels is set and registered for each of the display means, distributed to a required display means at a predetermined rewrite timing via the network line, and a password input from a higher-level device is set. Is transmitted to the display means.In the display means, the transmitted password is compared with a pre-registered password, and the operation from the higher-level device to each display means is performed in accordance with the password. A control device that limits each layer.