JP7629197B2 - Relay device, method and program - Google Patents

Description

The present invention relates to a relay device, a method for acquiring information from a machine, and a program.

The Modbus (registered trademark) TCP protocol is a communications protocol that uses a serial communications protocol developed by Modicon for its PLCs (Programmable Logic Controllers) on TCP/IP.

There is known a relay device that collects information from industrial machines such as CNCs, lathes, and laser processing machines operating in factories and distributes the collected information at a time desired by the user using the Modbus TCP protocol. Specifically, in Patent Document 1, a client device transmits request information to the relay device, and the relay device transmits acquired data stored in the memory unit of the relay device to the client device in response to the request information. As a result, the client device holds the acquired data from the relay device in the memory unit.

JP 2017-046250 A

However, when a user operates a client device to collect information such as the operating status of industrial machinery through a relay device, even if the industrial machinery is unable to communicate with the relay device, the user is unable to know this.

In addition, even if the address, which is the location information in memory used to identify the industrial machine information that is being attempted to be obtained through the relay device by operating the client device, is specified as different from the industrial machine information identified within the address range managed by the relay device, the user cannot know this.

Furthermore, in the above-mentioned Modbus protocol, the request information sent by the client device when obtaining information on industrial machines through a relay device does not include a parameter that directly specifies the industrial machine desired by the user, which creates the problem that the information obtained may differ from the information desired by the user.

The present invention was made in consideration of the above problems, and aims to notify a user of whether communication with an industrial machine is possible when acquiring information from the industrial machine using a relay device that uses the Modbus protocol, and to notify the user that an attempt has been made to acquire information from the industrial machine by specifying an invalid address range.

In order to achieve the above object, a relay device according to one aspect of the present invention is a relay device that relays communication between an industrial machine and a client device in accordance with a Modbus (registered trademark) protocol, and includes an acquisition unit that acquires data related to the industrial machine, a memory unit that stores an industrial machine system correspondence table in which the acquired data acquired by the acquisition unit and the system number of the industrial machine correspond to the address range in which the acquired data is stored, a communication unit that receives a machine data acquisition request from the client device, a determination unit that determines whether communication with the industrial machine is possible and whether the address range included in the machine data acquisition request is within the address range defined in the industrial machine system correspondence table , and a generation unit that notifies the determination result of the determination unit. and a generation unit that (a) generates response data including an exception code when it is determined that communication with the industrial machine is not possible, and (b) when it is determined that communication with the industrial machine is possible, (a) generates response data including the acquisition data identified by the address when it is determined that the address range included in the machine data acquisition request is within the address range defined in the industrial machine system correspondence table, and (b) generates response data including the exception code when it is determined that the address range included in the machine data acquisition request is outside the address range defined in the industrial machine system correspondence table, and the communication unit further transmits the response data generated by the generation unit to the client device.

According to this, the user can know that data acquisition from the relay device has failed due to setting an incorrect address range in the client device for acquiring the desired machine data of the industrial machinery system, by receiving response data including an exception code. Also, if the relay device cannot establish communication with the industrial machinery, the user can know that data acquisition has failed by receiving response data including an exception code. Note that the "address range" referred to here is a higher-level concept that includes the combination of the data start address and address range exemplified using Figure 3 etc. in the [Mode for implementing the invention].

The relay device may be connected to a plurality of industrial machines and may have a plurality of communication ports corresponding to each of the plurality of industrial machines, the storage unit may further store a communication port number associated with each of the plurality of industrial machines, the machine data acquisition request may further include the communication port number, the determination unit may further determine whether or not the industrial machine associated with the communication port number included in the machine data acquisition request is connected to the relay device, (i) when it is determined that the industrial machine associated with the communication port number is not connected to the relay device, the determination unit may notify the generation unit of the determination result that communication with the industrial machine is not possible, and (ii) when it is determined that the industrial machine associated with the communication port number is connected to the relay device, the determination unit may notify the generation unit of the determination result that communication with the industrial machine is possible.

According to this, in a configuration in which multiple industrial machines are connected to one relay device, the relay device can identify, via a client device, which industrial machine's industrial machine system the user desires acquired data for, and can transmit response data including the appropriate acquired data to the client device. This allows the user to know the appropriate acquired data.

Further, a method for providing a client device with information from an industrial machine according to a Modbus protocol according to one aspect of the present invention includes an acquisition step of acquiring data related to the industrial machine, a step of storing an industrial machine system correspondence table in which the acquired data acquired by the acquisition step , the system number of the industrial machine, and an address range in which the acquired data is stored are associated with each other, a receiving step of receiving a machine data acquisition request from the client device, a determination step of determining whether communication with the industrial machine is possible and whether the address range included in the machine data acquisition request transmitted by the client device is within the address range defined in the industrial machine system correspondence table stored in the storage unit, and a generating step, in accordance with a notification of the determination result of the determination step: (a) when the determination step determines that communication with the industrial machine is not possible, generating response data including an exception code; (b) when the determination step determines that communication with the industrial machine is possible, and (a) when the determination result is that the address range included in the machine data acquisition request is within the address range defined in the industrial machine system correspondence table, generating response data including the acquisition data identified by the address ; and (b) when the determination result is that the address range included in the machine data acquisition request is outside the address range defined in the industrial machine system correspondence table, generating response data including the exception code; and a transmitting step of transmitting the response data generated in the generating step to the client device.

With this, the user can learn that data acquisition from the relay device has failed due to an incorrect address range being set in the client device for acquiring machine data of the desired industrial machinery system, by receiving response data including an exception code. Also, if the relay device cannot establish communication with the industrial machinery, the user can learn that data acquisition has failed by receiving response data including an exception code.

Another aspect of the present invention is a program for causing a computer to execute the above-described method.

According to the present invention, a user can properly obtain information about industrial machinery through a relay device that uses the Modbus protocol, improving the convenience of the relay device.

FIG. 1 is a schematic diagram showing an overview of a communication system according to an embodiment of the present invention. FIG. 2 is a block diagram showing a functional configuration of a relay device according to an embodiment of the present invention. FIG. 3 is a diagram showing an example of a table showing the correspondence between the line number and the address range of the industrial machine according to the embodiment of the present invention. FIG. 4 shows an example of an acquired data correspondence table that is stored in advance in the relay device according to the embodiment of the present invention. FIG. 5 is a diagram showing another example of the acquired data correspondence table stored in advance in the relay device according to the embodiment of the present invention. FIG. 6 is a flowchart showing the operation of the relay device according to the embodiment of the present invention. FIG. 7 is a sequence diagram showing the flow of operations in the communication system according to the embodiment of the present invention when the line number and address range of the industrial machine specified by the client device are correct. FIG. 8 is a sequence diagram showing the flow of operations in the communication system according to the embodiment of the present invention when the line number and address range of the industrial machine specified by the client device are incorrect. FIG. 9 is a sequence diagram showing a flow of operations in a case where the relay device cannot communicate with the industrial machine in the communication system according to the embodiment of the present invention.

Hereinafter, the embodiment will be specifically described with reference to the drawings.
The embodiments described below each show a preferred specific example of the present invention. The numerical values, shapes, materials, components, the arrangement and connection of the components, steps, and the order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the following embodiments, those components that are not described in the independent claims showing the highest concept of the present invention are described as any components that constitute a more preferred embodiment. Note that the same components are given the same reference numerals and descriptions may be omitted.

(Embodiment)
In this embodiment, a communication system will be described which acquires data of an industrial machine by specifying an address range, which is location information in a memory for identifying information of the industrial machine that uses an industrial communication protocol.

FIG. 1 is a schematic diagram showing an overview of a communication system 100 according to an embodiment of the present invention.
1, the communication system 100 includes an industrial machine 101, a relay device 102, a network 103, and a client device 104. The communication system 100 is, for example, a communication system established in a factory.

In this embodiment, the communication system 100 includes one industrial machine 101, but is not limited to this and may include multiple industrial machines 101. In this embodiment, the communication system 100 includes one client device 104, but is not limited to this and may include multiple client devices.

Specifically, the industrial machine 101 is composed of a CNC (numerical control device) or a cutting machine. The industrial machine 101 is connected to the relay device 102 via a communication link 106. The communication link 106 is realized by wired communication conforming to the RS-232C or IEEE802.3 standard, or wireless communication conforming to the IEEE802.11n or ac standard, and is a communication path between the industrial machine 101 and the relay device 102. Note that the communication link 106 may be composed of a wired or wireless network when communication is performed between multiple industrial machines 101 and the relay device 102.

The relay device 102 is connected to the client device 104 via the network 103. The relay device 102 acquires data related to the industrial machine 101 via the communication link 106. The relay device 102 also transmits the acquired data related to the industrial machine 101 to the client device 104 via the network 103.

The network 103 is a network in which communication is performed using, for example, TCP (Transport Control Protocol). The network 103 is realized by wired communication conforming to, for example, the IEEE 802.3 standard, or wireless communication conforming to, for example, the IEEE 802.11n or ac standard. Furthermore, the network 103 is not limited to the connection only between the industrial machine 101 and the relay device 102, but is a general-purpose network to which any device conforming to the standard can be connected and communication can be performed.

The client device 104 is connected to the relay device 102 via the network 103. The client device 104 transmits a request for data related to the industrial machine 101 to the relay device 102 via the network 103 in response to an operation by the user 105 or the like. The client device 104 is also a terminal device that receives data related to the industrial machine 101 collected by the relay device 102 via the network 103 and displays the data on a display unit (not shown) of the device itself. Specifically, the client device 104 is a personal computer, a tablet computer, a smartphone, or the like.

FIG. 2 is a block diagram showing the functional configuration of the relay device 102 according to this embodiment. The relay device 102 includes an acquisition unit 201, a determination unit 202, a storage unit 203, a generation unit 204, and a communication unit 205.

The acquisition unit 201 acquires information about the industrial machine 101. The acquisition unit 201 collects information from the industrial machine 101 and stores it in the memory unit 203. Information that can be collected from the industrial machine 101 includes, for example, the model number of the industrial machine, the industrial machine system number, basic information about the industrial machine 101, and data that can be acquired by sensors built into the industrial machine. The collected information also includes, but is not limited to, information about the operation of the industrial machine 101, such as the operating state of the CNC, the rotation speed of the machining shaft, and the rotation load of the machining shaft, and also includes information about the communication state between the relay device 102 and the industrial machine 101.

Based on the request information (hereinafter also referred to as a machine data acquisition request) including address range information acquired by the communication unit 205 from the client device 104, the determination unit 202 determines whether the information (hereinafter also referred to as acquired data) acquired by the acquisition unit 201 stored in the storage unit 203 from the industrial machine 101 is within the address range. The determination unit 202 also determines whether communication with the industrial machine 101 connected to the relay device 102 is possible. The determination unit 202 notifies the generation unit 204 of the determination result. In addition to the address range, the machine data acquisition request also includes information on a device address for identifying the relay device 102 and a function code (e.g., 04 (Read input registers)) for controlling the operation of the relay device 102. The address range is, for example, a combination of the data start address 302 and the address range 303 in FIG. 3 described later, but is not limited thereto, and may be, for example, a combination of the data start address and the data end address.

The storage unit 203 stores the data acquired by the acquisition unit 201 from the industrial machine 101, the system number to which the industrial machine 101 belongs, and the address range linked to the system to which the industrial machine 101 belongs. The storage unit 203 also stores an exception code that responds to a request from the client device 104 when the request is invalid. The exception code may be set by the user 105 (administrator) using a setting tool (not shown) or the like and stored in the storage unit 203, or may be stored in advance at the time of shipment from the factory. A specific example of the exception code is "02 (Illegal Data Address)". The storage unit 203 is realized by a non-volatile memory such as an eMMC (Embedded MultiMediaCard) (registered trademark) or an SSD (Solid State Drive). In addition, in this embodiment, the storage unit 203 is described as a non-volatile memory, but some of its functions may be configured using RAM (volatile memory).

The generation unit 204 generates response data including either the data acquired by the acquisition unit 201 from the industrial machine 101 or an exception code based on the judgment of the judgment unit 202. The generation unit 204 receives notification of the judgment result of the validity of the address range related to the data acquired from the industrial machine 101 from the judgment unit 202, and generates response data. Specifically, if the data start address is valid, the generation unit 204 generates response data including the acquired data specified by the address, and if the data start address is invalid, the generation unit 204 generates response data including an exception code. Furthermore, if the generation unit 204 receives notification of the judgment result from the judgment unit 202 that communication with the industrial machine is impossible, the generation unit 204 generates response data including an exception code.

The communication unit 205 receives a machine data acquisition request sent by the client device 104. In addition, the communication unit 205 transmits to the client device 104 response data that includes either the data acquired from the industrial machine 101 or an exception code, which is generated by the generation unit 204 in response to the request from the client device 104.

3 is an example of an industrial machine system correspondence table 300 in which the system number (e.g., the number for each CNC) of each industrial machine stored in advance in the memory unit 203 of the relay device 102 corresponds to the address range in which the information of the industrial machine is stored. The industrial machine system correspondence table 300 is composed of data including an industrial machine system 301, a data start address 302, and an address range 303. More specifically, in the first row shown in FIG. 3, the industrial machine system 301 indicates "industrial machine system 1", and data that can be obtained from the industrial machine is stored from the start position "100" of the data start address 302 to the range "100" of the address range 303 (i.e., from the address position 100 to the address position 199). In this embodiment, the industrial machine system 1 and the industrial machine system 2 are stored, but this is not limited to this. Note that the industrial machine system 301 is information for individually identifying multiple CNCs that may be included in one industrial machine 101.

Figure 4 shows an example of an acquired data correspondence table 400, which is stored in advance by the relay device 102 and which associates each address (address start position) and the address range for each piece of data (acquired data) that can be acquired from an industrial machine. Note that Figure 4 shows an example in which the address and its range for each piece of data in the industrial machinery system 1 are stored. The acquired data correspondence table 400 is composed of data including acquired data 401, a data start address 402, and an address range 403. The data start address 402 indicates the start position of each piece of acquired data information shown in the acquired data 401. The address range 403 stores information such as the number of bytes that specifies the range in which the data corresponding to the data start address 402 is stored, but is not limited to this. More specifically, in the first row shown in FIG. 4, acquired data 401 is data indicating an "emergency stop state," and data start address 402 stores data acquired from the industrial machine (data indicating an emergency stop state) from start position "100" to address range 403 range "8" (i.e., addresses from 100 to 107).

Figure 5 is another example of the acquired data correspondence table of Figure 4. The acquired data correspondence table 500 shows a case where the addresses and ranges for each data of the industrial machinery system 2 are stored. In this way, the acquired data correspondence table 400 can store, for each of multiple industrial machinery systems, the data start address and the address range of each data (acquired data) acquired from the industrial machinery in correspondence with each other.

[Mode in which the industrial machinery and the relay device are controlled under one industrial machinery system]
Below, we will first explain the operation in a case where the industrial machine 101 has only one industrial machine system (industrial machine system 1), and the relay device 102 acquires data related to the industrial machine system 1 from the industrial machine 101 and stores it in the memory unit 203 as shown in Figure 4.

FIG. 6 is a flowchart showing the operation of the relay device 102 according to this embodiment.
Step S601 is a step of receiving a machine data acquisition request transmitted by the client device 104 to the relay device 102 when the client device 104 attempts to acquire desired acquisition data from the industrial machine 101.

Step S602 is a step in which the relay device 102 determines whether communication with the industrial machine 101 is possible via the communication link 106.

Step S603 is a step for extracting information about the address range contained in the machine data acquisition request received in step S601.

Step S604 is a step of comparing the information of the data start address extracted in step S603 with the industrial machine system correspondence table 300 stored in the storage unit 203, and judging whether the range of the extracted address is within the address range defined by the data start address 302 and the address range 303 defined in the industrial machine system correspondence table 300. The judgment unit 202 judges whether a valid address range (data start address 302 and address range 303) is specified in response to the machine data acquisition request from the client device 104. If the judgment unit 202 judges that a valid address range is specified, it notifies the generation unit 204 of that fact (Yes in step S604). Specifically, for example, when the acquisition unit 201 acquires information related to the industrial machine system 1 equipped with the industrial machine from the industrial machine 101, the relay device 102 recognizes that the own machine is connected to the industrial machine belonging to the industrial machine system 1. According to the example of the table shown in the industrial machinery system correspondence table 300 in FIG. 3, the data start address "100" and the address range "100" are defined as a combination for "industrial machinery system 1", and the relay device 102 stores this information in advance in the storage unit 203. Therefore, if the value of the data start address extracted in the above-mentioned step S603 is a value that falls within the range of the combination (e.g., 132), it is determined that it is within a valid address range. On the other hand, if the determination unit 202 determines that a valid address range has not been specified, it notifies the generation unit 204 of that effect (No in step S604).

Step S605 is a step in which the generation unit 204 generates response data including the corresponding acquisition data based on the data start address and address range extracted in step S603, based on the notification from the determination unit 202 (Yes in step S604).

Step S606 is a step in which the generation unit 204 generates response data including an exception code based on the notification from the determination unit 202 (No in step S604).

Step S607 is a step in which the communication unit 205 transmits response data including either the acquired data or the exception code generated by the generation unit 204 in step S605 or step S606 to the client device 104.

[Relay device behavior when a client device specifies a valid address range]
Next, the operation when the relay device 102 receives a machine data acquisition request specifying a valid address range from the client device 104 will be described with reference to FIG. 6 and FIG. 7, which is a sequence diagram showing an example of the operation of the communication system 100 in this embodiment.

In the example shown in the present embodiment, the industrial machine 101 and the relay device 102 are connected in a one-to-one relationship by the communication link 106. In this configuration, the relay device 102 can grasp a plurality of industrial machine systems that may be provided in the industrial machine 101 and the address range of the acquired data corresponding to the industrial machine system (data start address 302 and address range 303) by storing the industrial machine system correspondence table 300 in advance. In addition, since the industrial machine system is recognized one-to-one by the relay device 101 and the data start address and address range of the machine are stored in advance in the storage unit 203 by the acquisition unit 201, the client device 104 does not need to include the industrial machine system number in the machine data acquisition request. As long as at least the information on the data start address 402 and the information on the address range 403 are included in the machine data acquisition request, the relay device 102 can specify the acquired data desired by the client device 104 using the above-mentioned information.

First, as shown in FIG. 7, when the client device 104 acquires data of the industrial machinery system 1 equipped in the industrial machinery 101, the client device 104 transmits a machine data acquisition request specifying an address range of 100 to 199 to the relay device 102 (step S701). For example, taking the acquired data correspondence table 400 in FIG. 4 as an example, the client device 104 specifies the data start address "100" and the address range of the desired data "8" in the machine data acquisition request to acquire acquired data indicating an "emergency stop state."

Next, the relay device 102 receives the machine data acquisition request (step S601) and extracts the data start address and address range information contained in the machine data acquisition request (step S603).

Then, based on the industrial machine lineage number 1 of the industrial machine 101 acquired by the acquisition unit 201 from the industrial machine 101 and pre-stored in the memory unit 203, and the corresponding address range (data start address 302 and address range 303), the relay device 102 determines that the address included in the machine data acquisition request extracted in step S603 is within the address range corresponding to the pre-stored industrial machine lineage number (Yes in step S604 in Figure 6, i.e. step S7604 in Figure 7).

Next, the relay device 102 acquires the acquisition data corresponding to the address specified by the client device 104, generates response data (step S605), and transmits the response data to the client device 104 (step S607). For example, taking the data shown in FIG. 4 as an example, if the client device 104 has specified the address range from 100 to 108, the data corresponding to that address range is "emergency stop status." Finally, the client device 104 receives the response data (not shown).

[Relay device behavior when a client device specifies an invalid address range]
Next, the operation of the relay device 102 when the relay device 102 receives a machine data acquisition request specifying an invalid address range from the client device 104 will be described with reference to FIGS.

First, as shown in Fig. 8, when the industrial machine system of the industrial machine 101 to which the relay device 102 is connected is the industrial machine system 1, for example, the client device 104 transmits a machine data acquisition request specifying an address range of 200 to 299 to the relay device 102 (step S801). For example, taking the table in Fig. 4 as an example, the client device 104 specifies the address "200" and the desired data range "8" in the machine data acquisition request to acquire acquisition data indicating an "emergency stop state".

Next, the relay device 102 receives the machine data acquisition request (step S601) and extracts the data start address and address range information contained in the machine data acquisition request (step S603).

Then, the relay device 102 determines, from the address range information corresponding to the pre-stored industrial machine system number and the industrial machine system number of the industrial machine 101 acquired by the acquisition unit 201, that the address range information acquired in step S603 (corresponding to the data start address and address range) is outside the pre-stored address range of the industrial machine system 1. (No in step S604 in FIG. 6, i.e. step S8604 in FIG. 8).

Finally, the relay device 102 generates response data including the exception code (step S606) and transmits the response data to the client device 104 (step S607).

As a result, the user 105 can learn by receiving response data including an exception code from the relay device 102 that data acquisition has failed due to an incorrect address range being set in the client device 104 for the acquisition information of the industrial machine 101 in the desired industrial machinery system.

[Operation of relay device when communication with industrial machinery is not possible]
Next, the operation when the relay device 102 cannot communicate with the industrial machine 101 will be described with reference to FIGS. 6 and 9. FIG.

First, as shown in FIG. 9, when the industrial system number of the industrial machine 101 to which the relay device 102 is connected is industrial machine system 1, the client device 104 transmits a machine data acquisition request specifying, for example, an address range of 100 to 199 to the relay device 102 (step S901). For example, using the table in FIG. 4 as an example, the client device 104 specifies the data start address "100" and the address range of the desired data "8" in the machine data acquisition request to acquire acquisition data indicating an "emergency stop state."

Next, the relay device 102 receives a machine data acquisition request (step S601).

Next, for example, if the power supply of the industrial machine 101 is turned off or the path of the communication link 106 is unavailable, the relay device 102 determines that communication with the industrial machine 101 is not possible (No in step S602 in FIG. 6, i.e., step S9602 in FIG. 9). Note that the method of determining whether communication with the industrial machine 101 is possible may be, for example, by checking a response using a PING protocol or by using a uniquely defined protocol.

Finally, the relay device 102 generates response data including the exception code (step S606) and transmits the response data to the client device 104 (step S607).

Accordingly, if the relay device 102 cannot establish communication with the industrial machine 101, the user 105 can know that data acquisition has failed by receiving response data that includes an exception code.

[Modification of the embodiment]
Although the embodiment of the present invention has been described above, the present invention is not limited to this.
In the following description, the components and symbols described in the above embodiment will be used, and a description of each component of this modified example will be omitted.
This modification differs from the above embodiment in that data is acquired by the relay device 102 for multiple systems of multiple industrial machines 101 in the communication system 100. Specifically, multiple industrial machines 101 may be connected to the relay device 102 via communication links 106, or one industrial machine may have multiple industrial machine systems. In this case, the relay device 102 assigns an arbitrary port number to each of the multiple industrial machines 101 connected to the relay device 102 and communicates with them. Furthermore, the relay device 102 includes an industrial machine system correspondence table 300 and an acquired data correspondence table 400 that are linked to each port number, for example.

The client device 104 acquires information related to the desired industrial machine 101 by specifying the port number to which the desired industrial machine 101 is connected and including information on the desired address range (data start address and address range) in a machine data acquisition request and sending it to the relay device 102.

The following describes the case where the relay device 102 acquires data from multiple industrial machines 101.

The client device 104 sends a machine data acquisition request to the relay device 102, including information on the data start address and address range.

The relay device 102 compares the industrial machine system correspondence table 300 associated with the specified port number with the address range (data start address and address range) included in the machine data acquisition request.

Specifically, for example, in the configuration of the communication system 100, when two industrial machines 101 are connected to the relay device 102, there will be multiple industrial machine systems from which the relay device 102 acquires data via the communication link 106. The client device 104 transmits a machine data acquisition request specifying the port number of the industrial machine 101 in order to identify which of the industrial machine systems contains the desired acquired data, including information on the data start address and address range. When the relay device 102 receives the machine data acquisition request, it determines whether or not there is an industrial machine 101 connected to it via the port number specified by the client device 104. If there is an industrial machine 101 connected to the relay device 102, the relay device 102 extracts the data start address and address range information included in the machine data acquisition request.

Then, the relay device 102 determines whether the address included in the extracted machine data acquisition request is within the address range corresponding to the pre-stored industrial machine lineage number based on the combination of the pre-stored industrial machine lineage number of the industrial machine 101 and the corresponding address range (data start address 302 and address range 303). If it is determined that the address is within the address range corresponding to the pre-stored industrial machine lineage number, it transmits response data including the acquisition data corresponding to the address included in the machine data acquisition request to the client device 104. On the other hand, if the relay device 102 determines that the address is outside the address range corresponding to the pre-stored industrial machine lineage number, it transmits response data including an exception code to the client device 104.

In addition, if the industrial machine 101 corresponding to the port number specified in the machine data acquisition request is not connected to the relay device 102 (including the case where the industrial machine 101 cannot be recognized), the relay device 102 transmits response data including an exception code to the client device 104.

According to this modified example, in a configuration in which multiple industrial machines 101 are connected to one relay device 102 via communication links 106, the relay device 102 can identify acquired data related to the industrial machine system of the industrial machine 101 desired by the user 105 via the client device 104, and can transmit response data including the appropriate acquired data to the client device 104. This allows the user 105 to know the appropriate acquired data.

In the above embodiment, each component may be configured with dedicated hardware, or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

The present invention can be applied to relay devices that communicate with industrial machines and client devices, for example, according to the Modbus communication protocol.

REFERENCE SIGNS LIST 100 Communication system 101 Industrial machine 102 Relay device 103 Network 104 Client device 105 User 106 Communication link 201 Acquisition unit 202 Determination unit 203 Storage unit 204 Generation unit 205 Communication unit 300 Industrial machine system correspondence table 301 Industrial machine system 302 Data start address 303 Address range 400 Acquired data correspondence table 401 Acquired data 402 Data start address 403 Address range 500 Acquired data correspondence table

Claims (3)

A relay device that relays communication between an industrial machine and a client device in accordance with a Modbus (registered trademark) protocol,
An acquisition unit that acquires data related to the industrial machine;
a storage unit that stores an acquired data correspondence table that associates the acquired data acquired by the acquisition unit with an address range in which the acquired data is stored, and an industrial machine system correspondence table that associates the system number of the industrial machine with the address range;
A communication unit for receiving a machine data acquisition request from the client device;
A determination unit,
a determination unit that determines whether communication with the industrial machine is possible and whether an address range included in the machine data acquisition request is within an address range defined in the industrial machine system correspondence table;
A generation unit,
According to the notification of the judgment result of the judgment unit,
(a) generating response data including an exception code when a determination result indicates that communication with the industrial machine is impossible;
(b) when the determination result indicates that communication with the industrial machine is possible,
(A) when it is determined that the address range included in the machine data acquisition request is within the address range defined in the industrial machine system correspondence table, generating response data including the acquisition data identified by the address;
(i) a generating unit that generates response data including the exception code when it is determined that the address range included in the machine data acquisition request is outside the address range defined in the industrial machine system correspondence table; and
a plurality of communication ports connected to a plurality of industrial machines and corresponding to each of the plurality of industrial machines;
Equipped with
Further, the storage unit stores a communication port number associated with each of the plurality of industrial machines,
The machine data acquisition request further includes the communication port number.
The determination unit further determines whether an industrial machine associated with the communication port number included in the machine data acquisition request is connected to the relay device,
(i) when it is determined that an industrial machine associated with the communication port number is not connected to the relay device, notifying the generation unit of a determination result that communication with the industrial machine is impossible;
(ii) when it is determined that an industrial machine associated with the communication port number is connected to the relay device, notifying the generation unit of a determination result that communication with the industrial machine is possible;
The communication unit transmits the response data generated by the generation unit to the client device.
Relay device. A method for providing information from an industrial machine to a client device according to a Modbus protocol by a relay device that relays communication between the industrial machine and the client device, the method comprising the steps of :
acquiring data relating to the industrial machine;
a storage step of storing an acquired data correspondence table in which the acquired data acquired by the acquiring step corresponds to an address range in which the acquired data is stored, and an industrial machine system correspondence table in which an industrial machine system number corresponds to the address range;
receiving a request to obtain machine data from the client device;
a determination step of determining whether communication with the industrial machine is possible and whether an address range included in the machine data acquisition request transmitted by the client device is within an address range defined in the industrial machine system correspondence table stored in the storage step;
Furthermore, in the storing step, a communication port number associated with each of the plurality of industrial machines is stored,
The machine data acquisition request further includes the communication port number.
In the determination step, it is further determined whether or not an industrial machine associated with the communication port number included in the machine data acquisition request is connected to the relay device;
(i) when it is determined that the industrial machine associated with the communication port number is not connected to the relay device, notifying a determination result that communication with the industrial machine is impossible;
(ii) when it is determined that an industrial machine associated with the communication port number is connected to the relay device, notifying a determination result that communication with the industrial machine is possible;
A generating step,
According to the notification of the judgment result of the judgment step,
(a) generating response data including an exception code when a determination result indicates that communication with the industrial machine is impossible in the determining step;
(b) a determination result that communication with the industrial machine is possible in the determination step,
(A) when it is determined that the address range included in the machine data acquisition request is within the address range defined in the industrial machine system correspondence table, generating response data including the acquisition data identified by the address;
(i) generating response data including the exception code when it is determined that the address range included in the machine data acquisition request is outside the address range defined in the industrial machine system correspondence table;
a transmitting step of transmitting the response data generated in the generating step to the client device.
method. A program causing a computer to execute the method according to claim 2.