JP2011065267A - Control system, programmable display, and server device for control - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control system small in restriction for constructing the system and high in both convenience and security in a case where a server device for control controls a programmable display. <P>SOLUTION: The control system includes a plurality of programmable displays 1 and a server device 2 for control, and the programmable displays 1 are communicably connected with the server device 2 for control via the Internet 4. Each of the programmable displays 1 has an interface unit 12 which performs polling on the server device 2 for control by a GET command of HTTP and receives a request by a reply from the GET command. In the system, the polling to be transmitted from the programmable displays 1 to the server device 2 for control includes the information capable of specifying a transmission origin, and the server device 2 for control has a CPU 21 determining validity of the polling on the basis of the information capable of specifying the transmission origin. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control system including a plurality of programmable displays and a control server device for controlling them, and a programmable display and a control server device used in the control system.

  Conventionally, in a control system including a plurality of programmable displays and a control server device for controlling them, the control server device and a client device accessible to the control server device may be connected via the Internet. However, the plurality of programmable displays and the control server device that controls them are connected by a dedicated network (LAN) (see, for example, Patent Document 1).

International Publication No. 01/69334 (Fig. 1) JP 2001-5746 A (FIG. 1, paragraph 0031)

  In a conventional control system, a plurality of programmable displays and a control server device that controls them are connected to the same LAN. Therefore, the installation location of the control server device is limited to the LAN area, and the control server The control target of the device is limited to a programmable display connected to the same LAN. In other words, in the conventional control system, there are large restrictions in constructing the system.

  Therefore, it is conceivable that the control server device is provided on the Internet so that the control server device and the programmable display device perform Internet communication. However, the programmable display device connected to the LAN is the control server on the Internet. When polling a device for a request or when a control server device on the Internet sends a request to a programmable display connected to the LAN, a firewall normally provided in the LAN becomes a failure and polling and request transmission cannot be performed. There is a fear. If a firewall becomes an obstacle, it can be dealt with by setting up a relay server or changing the firewall settings, but such a countermeasure has the disadvantage that it requires appropriate expertise. Furthermore, it is often considered that firewall configuration changes themselves are not allowed from a security perspective.

  Moreover, since the programmable display connected to the LAN is configured to poll the control server device on the Internet, it is necessary to ensure security by identifying whether the polling is illegal. There is.

  Patent Document 2 discloses a file transfer system that transfers an electronic file from a transmission client to a reception client via a transfer server. The file transfer system disclosed in Patent Document 2 is complicated to install a transfer server. That is, the transfer server of the file transfer system disclosed in Patent Document 2 corresponds to a relay server, and is completely different from the control server device of the control system described above.

  In view of the above situation, the present invention is used in a control system that is less constrained in constructing the system and has high convenience and security when the control server device controls the programmable display device and the control system. It is an object of the present invention to provide a programmable display device and a control server device.

  In order to achieve the above object, a control system according to the present invention includes a plurality of programmable displays and a control server device, and the programmable displays are connected to the control server device via the Internet so as to communicate with each other. The programmable display device has communication means for performing polling to the control server device with a GET command of HTTP or a protocol that is an extension of HTTP, and receiving a request by returning the GET command. The polling transmitted from the programmable display to the control server device includes information that can identify the transmission source, and the programmable server displays the programmable display based on the information that allows the control server device to identify the transmission source. Validity of polling transmitted from the device to the control server device To have a determination means.

  In consideration of the limited amount of data that can be stored in the programmable display, the response to the GET command includes the execution condition of the request and a data set that is the execution content of the request. And the programmable display determines whether to save the request execution condition and the data set or only the request execution condition when the request is received according to the amount of data of the request. You may do it.

  Further, from the viewpoint of ensuring security more reliably, a password is included in polling transmitted from the programmable display to the control server device, and the determination means can identify the transmission source and the password Based on the above, the validity of polling transmitted from the programmable display to the control server device may be determined.

  In order to achieve the above object, a programmable display according to the present invention is a programmable display capable of communicating with a control server device via the Internet, and polls the control server device with HTTP. Alternatively, communication means that performs a protocol that extends HTTP is provided, and polling that is transmitted from the programmable display device to the control server device includes information that can specify a transmission source.

  In order to achieve the above object, a control server device according to the present invention is a control server device capable of communicating with a programmable display device via the Internet, and is controlled from the programmable display device to the control server device. Based on the information that can specify the transmission source included in the polling transmitted to the apparatus, a determination unit that determines the validity of the polling transmitted from the programmable display to the control server apparatus is provided.

  According to the present invention, the programmable display device has a communication means for performing polling to the control server device with a GET command of HTTP or a protocol obtained by extending HTTP, and receiving a request by returning the GET command. Data can be transmitted from the control server device on the Internet to the programmable display without any particularly difficult settings for the firewall, and convenience is improved. Moreover, according to this invention, based on the information which can specify the transmission source contained in the poll transmitted to the control server apparatus from the programmable display to the control server apparatus from the programmable display to the control server apparatus. Since the determination means for determining the validity of the transmitted polling is provided, security can be ensured.

It is a figure showing an example of 1 composition of a control system concerning the present invention. It is a figure which shows the directory structure of HDD which the server apparatus for control comprises. It is a flowchart which shows operation | movement when the server apparatus for control receives the data transmitted from a programmable display or local PC. It is a flowchart which shows the polling operation | movement of a programmable display. It is a flowchart of a polling information reception process. It is a flowchart of a reply data process. It is a flowchart of a request setting information transmission process. It is a flowchart of a request setting information reception process. It is a flowchart of a data update execution process. It is a flowchart of the preservation | save process of the uploaded file. It is a flowchart of a file acquisition process. It is a flowchart of a file acquisition request reception process.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration example of a control system according to the present invention.

  The control system shown in FIG. 1 includes a plurality of programmable displays 1 and a control server device 2 that controls them.

  A certain administrator (one company, one office, one factory, etc.) may inappropriately leak data from the LAN (Local Area Network) 3 and the LAN 3 to the Internet 4 or inappropriate from the Internet 4 to the LAN 3. A firewall 5, a programmable display 1, a PLC 6, and a device 7 that prevent inflow of data are provided in a specific area. In FIG. 1, only the LAN 3 for one administrator, the firewall 5, the programmable display 1, the PLC 6, and the device 7 are shown, but the control server device 2 is a programmable display 1 for one administrator. It is not limited to what controls only, but the thing which controls the programmable display 1 for several managers may be used.

  The programmable display 1 can communicate with the control server device 2 via the LAN 3, the firewall 5, and the Internet 4.

  The PLC 6 executes the control program (ladder program) created by the user to capture the state of the input device 7 at every predetermined scan time such as several tens of ms, and to output the device. 7 is given a control instruction.

  Examples of the input device 7 include a switch and a sensor, and examples of the output device 7 include a lamp and a bulb. These various devices 7 are arranged in required parts of various target systems such as a production line.

  Next, the configuration of the programmable display device 1 will be described. The programmable display 1 includes a CPU (Central Processing Unit) 11, interface units 12 and 13, SRAM (Static RAM) 14, FEPROM (Flash Erasable and Programmable ROM) 15, DRAM (Dynamic RAM) 16, and display. A device 17 and a touch panel 18 are provided.

  As will be apparent from the description below, the interface unit 12 functions as an example of “communication means” in the claims.

  The interface unit 12 is a communication control unit for the programmable display 1 to communicate with the control server device 2, and is connected to the Internet 4 through the LAN 3 and the firewall 5. The interface unit 12 is configured to perform network communication using HTTP (Hyper Text Transfer Protocol).

  The interface unit 13 is a communication control unit for the programmable display device 1 to communicate with the PLC 6. The interface unit 13 performs serial communication using a communication protocol according to the manufacturer and model of the PLC 6 when the PLC 6 is a model that performs serial communication, and performs network communication when the PLC 6 is a model that performs network communication. Configured to do.

  The SRAM 14 is a data memory that stores data obtained from the PLC 6 and data generated by the programmable display 1.

  Sampling data is an example of data obtained from the PLC 6. The sampling data is data obtained by the PLC 6 from the device 7 and is stored in the SRAM 14 in the order of generation.

  Examples of data generated by the programmable display 1 include alarm data, line graph data, and operation log data.

  The alarm data is information regarding the alarm. When the CPU 11 receives that a predetermined alarm bit in the PLC 6 is turned on, the CPU 11 creates contents (messages) and the like regarding the alarm set in advance for the alarm bit together with the issue time (reception time). The line graph data is data for displaying a line graph. The CPU 11 creates line graph data based on the sampling data. The operation log data is data relating to the user's operation history with respect to the programmable display 1, and details of operations performed by the user on the programmable display 1 (login, logout, touch operations on the screen, etc.) and operator information ( Name, affiliation, etc.) and the time of occurrence.

  The FEPROM 15 stores screen data, display / control programs, communication protocol data, communication programs, protocol conversion programs, ladder programs, ladder processing programs, and the like. These various data and programs may be stored in the FEPROM 15 in advance, or may be read from a storage medium such as a CD-ROM by the storage medium playback unit so that the program display 1 is provided with a storage medium playback unit. It may be stored in the FEPROM 15 in advance. These various data and programs may be transferred from the control server device 2 to the programmable display 1 and stored in the FEPROM 15, for example.

  The screen data is data of a screen (user screen) displayed on the display device 17, data of a base screen, data of imaged parts such as switches and lamps, and processing instruction words given to each part. (Tag).

  The above tag is created for each event to be executed on the base screen. Basically, the file number of the base screen on which the display control operation is to be executed and the operation to be executed on this base screen. An event name for specifying the contents and reference information including one or more data referred to for each execution event are provided as a set. For example, when the tag is a display tag that displays a part graphic corresponding to the content of a predetermined device address in a predetermined screen area (display coordinate range), the reference information includes a coordinate range (X, Y) for display. And a file number for specifying a display target and a predetermined device address indicating a predetermined state of the display target. When the tag is an input tag, the reference information includes an effective input coordinate range (X, Y) and a device address where the input result is written.

  The DRAM 16 is a work memory used for temporary storage of data exchanged with the PLC 6 in addition to being used for work during arithmetic processing such as display control.

  The display device 17 is preferably a thin display device such as a liquid crystal display device, an EL display device, or a plasma display device.

  The touch panel 18 is an input device arranged on the display screen of the display device 17 in order to perform touch input on the display screen of the display device 17.

  Next, the configuration of the control server device 2 will be described. The control server device 2 includes a CPU 21, an interface unit 22, a RAM 23, a ROM 24, and an HDD (Hard Disk Drive) 25.

  As will be apparent from the description below, the CPU 21 functions as an example of the “determination unit” in the claims.

  The CPU 21 controls the programmable display device 1 by controlling the operation of the entire control server device 2.

  The interface unit 22 is a communication control unit for the control server device 2 to communicate with the programmable display 1 and is connected to the Internet 4. The interface unit 22 is configured to perform network communication using HTTP.

  The RAM 23 is a work memory in which a work area of the CPU 21 is set.

  The ROM 24 stores communication protocol data, a communication program, and the like.

  The HDD 25 is a large-capacity storage device, and its directory structure is, for example, as shown in FIG. A plurality of “programmable display ID” directories are contained in the “manager ID (identification)” directory. Each “programmable display ID” directory has “country identification code”, “company”, and “installation location” indicating the location of the programmable display as property information. Each “programmable display ID” directory includes a “request” directory, a “data” directory, a “file” directory, a “communication log” directory, and the like. Data related to requests for programmable displays is stored in the “Request” directory, data related to the data update function is stored in the “Data” directory, and file transfer functions are stored in the “File” directory. Related files and data are stored, and communication log data related to network communication is stored in the “communication log” directory. The administrator ID is a unique value that is different for each administrator, and the programmable display ID is a unique value that is different for each programmable display. Therefore, each programmable display 1 can be specified by an administrator ID and a programmable display ID.

  In addition to the control server device 2 configured as described above, a local PC (Personal Computer) 8 is also connected to the Internet 4.

  Next, an operation when the control server device 2 having the above configuration receives data transmitted from the programmable display 1 or the local PC 8 will be described with reference to a flowchart shown in FIG. The data transmitted by the HTTP from the programmable display 1 includes its own programmable display ID, password, and information (function information) indicating which function of the control system is related to the function in the header part. The data is transmitted by HTTP after being subjected to encryption processing. The data transmitted by HTTP from the local PC 8 includes the programmable display ID of the programmable display targeted by the data, the password, and the function information in the header portion, and after the encryption processing is performed, the HTTP Sent by.

  When the CPU 21 of the control server device 2 receives data transmitted by HTTP from the programmable display 1 or the local PC 8, it performs a decoding process on the received data (step S10). Then, the CPU 21 of the control server device 2 determines whether there is a problem in the validity of the received data based on the programmable display ID and password included in the header portion of the received data (step) S20).

  If there is a problem with the legitimacy of the received data such as the programmable display ID is different from the preset format or the password is different (YES in step S20), the CPU 21 of the control server device 2 The fact that there is an error in the programmable display ID or password is returned to the transmission source (step S30), and the operation of the flowchart shown in FIG.

  On the other hand, if there is no problem in the validity of the received data (NO in step S20), the CPU 21 of the control server device 2 determines a function related to the received data and performs a process according to the determination result. This is done (step S40), and the operation of the flowchart shown in FIG.

  Hereinafter, as a function example of the control system shown in FIG. 1, a polling function, a data update function, and a file transfer function from the control server device 2 to the programmable display device 1 will be sequentially described.

  First, the polling function will be described. The programmable display 1 performs the operation of the flowchart shown in FIG. That is, the programmable display device 1 performs polling (inquiry) on the request to the control server device 2 (step S110), and then performs processing according to the return data from the control server device 2 (step S120). . In step S110, the CPU 11 of the programmable display device 1 creates polling information by applying encryption processing to the header data including its own programmable display ID, password, and function information added to the empty data. To do. The polling information is transmitted by the interface unit 12 to the control server device 2 via the LAN 3, the firewall 5, and the Internet 4 using an HTTP GET command. Details of step S120 will be described later. The operation of the flowchart shown in FIG. 4 is started at every predetermined polling cycle in principle, but polling at a predetermined polling cycle is not performed during the process of step S120 (see FIG. 6 described later). ).

  The control server device 2 that has received the polling information performs the operation of the flowchart shown in FIG. 3, and performs polling information reception processing in step S40. FIG. 5 shows a flowchart of the polling information reception process.

  In the polling information reception process, first, the CPU 21 of the control server device 2 determines whether or not the polling information transmission source programmable display device is registered based on the header portion of the received polling information and the directory structure shown in FIG. Determination is made (step S210). If the transmission source programmable display is not yet registered (NO in step S210), a “programmable display ID” directory corresponding to the transmission source programmable display is newly created, and the transmission source programmable display is newly registered. (Step S220), and then the process proceeds to Step S230. On the other hand, if the transmission source programmable display has already been registered (YES in step S210), the process directly proceeds to step S230. In step S230, the CPU 21 of the control server device 2 refers to the status of the request data stored in the “request” directory in the “programmable display ID” directory corresponding to the transmission source programmable display, and transmits the request data. The content of the request that has not been sent to the original programmable display is set, a reply to the GET command is sent to the transmission source programmable display, and then the polling information reception process is terminated.

  When the transmission source programmable display receives the reply data from the control server device 2, the transmission source programmable display performs the reply data processing in step S120. Details of the reply data processing in step S120 are shown in the flowchart of FIG. The CPU 11 of the transmission source programmable display stops polling at a predetermined polling cycle (step S310), decodes the reply data, saves the content of the reply data in the FEPROM 15 (step S320), and then the predetermined polling cycle. Is restarted (step S330), and the reply data processing is terminated.

  Next, the data update function will be described. The local PC 8 performs the operation of the flowchart shown in FIG. That is, the local PC 8 adds a header part including a programmable display ID, a password, and function information of a programmable display that is a request target to the request data by an installed request setting application. Encryption processing is performed to create request setting information (step S410). This request setting information is transmitted to the control server device 2 via the Internet 4 by an HTTP command (step S420).

  The control server device 2 that has received the request setting information performs the operation of the flowchart shown in FIG. 3, and performs request setting information reception processing in step S40. FIG. 8 shows a flowchart of the request setting information reception process.

  In the request setting information reception process, first, the CPU 21 of the control server device 2 displays the contents of the received request setting information in the “request” directory in the “programmable display ID” directory corresponding to the programmable display that is the request target. (Step S510) and the received request setting information in the data of the setting request list stored in the “request” directory in the “programmable display ID” directory corresponding to the programmable display that is the target of the request. Is added (step S520), and the request setting information reception process is terminated. The setting request list data includes the setting date and time of each request (the reception date and time of request setting information corresponding to each request).

  The programmable display 1 performs polling by the above-described polling function, and performs reception processing of return data for the polling. When the execution condition of the request included in the content of the reply data is satisfied, the programmable display 1 performs the operation of the flowchart shown in FIG.

  The CPU 11 of the programmable display 1 updates the internal data of the PLC 6 using the data stored in the SRAM 14 and the FEPROM 15 or the interface unit 13 based on the stored data set (step S610).

  Finally, a file transfer function from the control server device 2 to the programmable display device 1 will be described. For example, the local PC 8 can upload a file to the control server device 2 by logging in to the file registration page of the control server device 2 using application software such as a known Web browser. At the time of uploading, the programmable display device 1 to be transferred is selected. When the local PC 8 uploads the file to the control server device 2, the CPU 21 of the control server device 2 performs the operation of the flowchart shown in FIG. 11, and stores the “programmable display ID” directory corresponding to the selected programmable display. The file is stored in the “file” directory (step S710), and the data in the file list stored in the “file” directory in the “programmable display ID” directory corresponding to the selected programmable display is Add an item for the uploaded file.

  When the file display is instructed by a user operation on the touch panel 18, the programmable display device 1 starts the operation of the flowchart shown in FIG. The CPU 11 of the programmable display device 1 adds a header portion including its own programmable display ID, password, and function information to the file specifying data (data for specifying a file to be acquired). Apply the encryption process and create a file acquisition request. This file acquisition request is transmitted by the interface unit 12 to the control server device 2 via the LAN 3, the firewall 5, and the Internet 4 as an HTTP command (step S810).

  The control server device 2 that has received the file acquisition request performs the operation of the flowchart shown in FIG. 3, and performs a file acquisition request reception process in step S40. In the file acquisition request reception process, the control server device 2 performs the operation of the flowchart shown in FIG. 12, sets the file specified by the file acquisition request as the reply content, and sends a reply to the GET command to the transmission source programmable display. (Step S910), and the file acquisition request receiving process is terminated. In response to this reply, the programmable display device 1 receives a file from the control server device 2 (step S820 in FIG. 11), and performs processing according to the setting of the screen components displayed on the display device 17 (for example, File content display) is executed (step S830).

  In the control system shown in FIG. 2 having the various functions described above, polling from the programmable display device 1 to the control server device 2 on the Internet is performed using an HTTP GET command. The programmable display device 1 responds by returning a GET command. A request has been received. In general settings of the firewall 5, a port is opened for HTTP, and therefore the control system shown in FIG. 1 having the various functions described above can control on the Internet without performing particularly difficult settings for the firewall 5. Data transmission from the server device 2 to the programmable display 1 is possible, and convenience is improved. Further, since the validity of the data received by the control server device 2 is determined using the header portion including the programmable display ID, it is possible to identify whether the polling is illegal in the control server device 2. And security can be ensured.

  As mentioned above, although embodiment which concerns on this invention was described, the range of this invention is not limited to this, A various change can be added and implemented in the range which does not deviate from the main point of invention.

  For example, in the above-described embodiment, the validity of the data received by the control server device 2 is determined by the programmable display ID and the password, but the password is not included in the header portion, and the control display is performed only by the programmable display ID. The validity of the data received by the server device 2 may be determined. On the contrary, the header part includes other elements (for example, access ID, country identification code, etc.), and the validity of the data received by the control server device 2 by the programmable display ID and the other elements. May be determined.

  For example, in the above-described embodiment, the interface units 12 and 22 perform network communication using HTTP. However, instead of HTTP, a protocol that extends HTTP may be used, or a protocol that extends HTTP or HTTP. Other protocols with open ports may be used as well as general firewall settings.

  The HTTP command is a GET command or a POST command by HTTP communication.

1 Programmable Display 2 Server Device for Control 3 LAN
4 Internet 5 Firewall 6 PLC
7 Device 8 Local PC
11 CPU
12, 13 Interface unit 14 SRAM
15 FEPROM
16 DRAM
17 Display device 18 Touch panel 21 CPU
22 Interface unit 23 RAM
24 ROM
25 HDD

Claims (4)

A control system comprising a plurality of programmable displays and a control server device, wherein the programmable display is communicably connected to the control server device via the Internet,
The programmable display has a communication means for performing polling to the control server device with a GET command of HTTP or a protocol obtained by extending HTTP, and receiving a request by returning the GET command,
Information that can identify the transmission source is included in polling transmitted from the programmable display to the control server device,
The control server apparatus includes a determination unit that determines validity of polling transmitted from the programmable display to the control server apparatus based on information that can specify the transmission source. . A password is included in polling transmitted from the programmable display to the control server device,
The said determination means determines the legitimacy of the polling transmitted from the said programmable display to the said server apparatus for control based on the information which can specify the said transmission source, and the said password. Control system. A programmable display capable of communicating with the control server device via the Internet,
Communication means for performing polling to the control server device using HTTP or a protocol that is an extension of HTTP,
Information that can specify a transmission source is included in polling transmitted from the programmable display to the control server device. A control server device capable of communicating with a programmable display via the Internet,
Based on information that can specify a transmission source included in polling transmitted from the programmable display to the control server device, the validity of polling transmitted from the programmable display to the control server device is determined. A control server device comprising: a determination unit that performs the determination.

Images