Network equipment and network systems

Abstract

To achieve a network device capable of easily identifying the affected range of a slave device on which an anomaly has occurred, even when the anomaly occurs on the slave device.SOLUTION: A control unit (24) of a network device (2N) causes an abnormality notification unit (23) to perform an abnormality notification when there is a reply from another slave device (2) stating that there is an abnormality, or when an abnormality is detected by an abnormality detection unit (22) and transmits an instruction to the other slave devices (2) registered in a configuration list to the effect that an abnormality notification should be performed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a network device and a network system using the same. [Background technology]

[0002] In the field of factory automation (FA), various types of devices that share the work process are controlled. In order to link various controllers, remote I / O, and manufacturing devices used for work in a certain area such as a factory facility, industrial networks, also called field networks, that connect these devices are constructed.

[0003] A typical industrial network uses a master-slave system consisting of various slave devices and a master device. The slave devices are devices that control the equipment installed in the factory or collect data. The master device is a device called a PLC (Programmable Logic Controller), for example, that centrally manages these slave devices.

[0004] A conventional slave device has a signal light, and the signal light is turned on to notify a user such as a manufacturing personnel of the operating state of the slave device (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-68239 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in a network system having the above-mentioned conventional slave devices, when an abnormality occurs in a slave device, it is difficult to identify the other slave devices linked to that slave device. In other words, in the conventional network system, when an abnormality occurs in a slave device, it is difficult to identify the scope of the effect of the slave device in which the abnormality occurs.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a network device and a network system that, even when an abnormality occurs in a slave device, makes it possible to easily identify the extent of the influence of the slave device in which the abnormality occurs. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present disclosure employs the following configuration.

[0009] A network device according to one aspect of the present disclosure is a network device which is a slave device used in a network system to which a master device and a plurality of slave devices controlled by the master device are connected, and which comprises: a communication unit which transmits and receives data between the other slave devices, an abnormality detection unit which detects abnormalities, an abnormality notification unit which executes an abnormality notification, a memory unit which pre-stores a configuration list of a group including the network device and at least one of the other slave devices, and a control unit which controls each unit of the network device, wherein the control unit is configured to inquire, via the communication unit, of the other slave devices registered in the configuration list as to whether or not there is an abnormality, and when the other slave device replies that there is an abnormality or when the abnormality detection unit detects an abnormality, to cause the abnormality notification unit to execute an abnormality notification, and to send, via the communication unit, an instruction to execute an abnormality notification to the other slave devices registered in the configuration list.

[0010] According to the above configuration, it is possible to configure a network device that, even when an abnormality occurs in a slave device, can easily identify the extent of the effect of the slave device in which the abnormality occurs.

[0011] In the network device relating to the above-mentioned aspect, the control unit may be configured to, when there is another slave device that does not reply to the inquiry, cause the abnormality notification unit to execute an abnormality notification, and to send an instruction to the other slave devices registered in the configuration list via the communication unit to execute an abnormality notification.

[0012] According to the above configuration, even if communication with another slave device registered in the configuration list is not possible, it is possible to determine that an abnormality has occurred in that other slave device, and to easily identify the scope of influence of the slave device in which the abnormality has occurred.

[0013] In the network device according to the aforementioned aspect, the abnormality notification unit may have a first light-emitting element, and the abnormality notification may be performed by lighting up the first light-emitting element.

[0014] According to the above configuration, the extent of the influence of a slave device in which an abnormality has occurred can be visually confirmed, and the extent of the influence can be more easily identified.

[0015] In the network device relating to the above aspect, the control unit may be configured to send, as the instruction, to a slave device among the other slave devices registered in the configuration list other than the slave device that has replied that there is an abnormality, an instruction to execute a first abnormality notification indicating that an abnormality has occurred in the slave device other than the slave device.

[0016] According to the above configuration, a slave device that is not experiencing an abnormality will execute an abnormality notification different from a slave device that has experienced an abnormality, making it easier to identify the slave device that has experienced an abnormality among the other slave devices registered in the configuration list.

[0017] In the network device relating to the above-mentioned aspect, the other slave device may have a second light-emitting element, and be configured to operate so as to cause at least one of the light-emitting state, light-emitting color, and light-emitting period of the second light-emitting element to differ when an instruction to execute the first abnormality notification is received and when the first abnormality notification is not received.

[0018] According to the above configuration, it is possible to easily determine whether or not an abnormality has occurred in another slave device registered in the configuration list, based on at least one of the light-emitting state, light-emitting color, and light-emitting period of the second light-emitting element.

[0019] In the network device relating to the above-mentioned aspect, the control unit may be configured to make at least one of the light emitting state, light emitting color, and light emitting period of the first light emitting element different between a case where the abnormality detection unit detects an abnormality and a case where the abnormality detection unit does not detect an abnormality.

[0020] According to the above configuration, in the network device, it is possible to easily determine whether or not an abnormality has occurred in the network device based on at least one of the light emitting state, light emitting color, and light emitting period of the first light emitting element.

[0021] Moreover, a network system according to one aspect of the present disclosure is a network system in which a master device and a plurality of slave devices controlled by the master device are connected, and is configured such that at least one of the network devices described above is connected as the slave device.

[0022] According to the above configuration, it is possible to configure a network system that, even when an abnormality occurs in a slave device, can easily identify the extent of the effect of the slave device in which the abnormality has occurred. Effect of the Invention

[0023] According to the present disclosure, it is possible to provide a network device and a network system that, even when an abnormality occurs in a slave device, can easily identify the extent of the effect of the slave device in which the abnormality has occurred. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is an explanatory diagram illustrating a configuration example of a network system according to a first embodiment of the present disclosure. [Diagram 2] 1 is a schematic configuration diagram showing a network device (slave device) according to a first embodiment of the present disclosure. [Diagram 3] 10 is a flowchart showing an operation of setting a configuration list of a control group in the network system. [Figure 4] 2 is a diagram showing a specific example of a configuration list set on the information processing device side shown in FIG. 1. FIG. [Diagram 5] FIG. 13 is a diagram showing a specific example of a configuration list set on the network device side. [Figure 6] FIG. 13 is a diagram showing a specific example of a configuration list set on the side of another network device. [Figure 7] 10 is a flowchart illustrating an example of the operation of the network device. [Figure 8] 10 is a flowchart illustrating an example of the operation of a network device according to a second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] [Embodiment 1] Hereinafter, an embodiment according to one aspect of the present invention (hereinafter, also referred to as "the present embodiment") will be described with reference to the drawings.

[0026] §1 Examples of application First, an example of a situation to which the present disclosure is applied will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is an explanatory diagram for explaining a configuration example of a network system according to a first embodiment of the present disclosure. Fig. 2 is a schematic configuration diagram showing a network device (slave device) according to the first embodiment of the present disclosure.

[0027] In the following description, a case will be described in which the network device of this embodiment, which is a slave device, has the same configuration as other slave devices as shown in Fig. 2. Also, in the network system 100 of this embodiment, for example, a case will be described in which eight slave devices 2A, 2B, 2C, 2D, 2E, 2F, 2G, and 2H (hereinafter collectively referred to as "2") are connected as multiple slave devices. Also, when a slave device is a network device according to this embodiment, it may be represented as network device 2N.

[0028] The network system 100 of this embodiment is a network system to which a master device 1 and a plurality of slave devices 2 controlled by the master device 1 are connected. Also, a network device 2N of this embodiment is connected to the network system 100 as one of the slave devices 2. In the network system 100 of this embodiment, at least one network device 2N is connected as a slave device 2.

[0029] The network system 100 of this embodiment also includes an information processing device 3. An administrator of the network system 100 can execute various settings of the master device 1 and the slave device 2, acquire data, and the like, through the information processing device 3. The network system 100 of this embodiment also includes a display device 4, which is capable of displaying the operating status of the network system 100, and the like.

[0030] Moreover, the network device 2N of this embodiment includes a communication unit 21 that transmits and receives data to and from other slave devices 2, an abnormality detection unit 22 that detects abnormalities, an abnormality notification unit 23 that executes abnormality notification, a storage unit 25 that stores in advance a configuration list of a control group (group) including the network device 2N and at least one other slave device 2, and a control unit 24 that controls each unit (component) of the network device 2N. The configuration list of the control group described above is set in advance in the storage unit 25 by the information processing device 3.

[0031] The control unit 24 inquires of the other slave devices 2 registered in the configuration list whether or not there is an abnormality through the communication unit 21. Then, when the other slave devices 2 reply that there is an abnormality, or when the abnormality detection unit 22 detects an abnormality, the control unit 24 causes the abnormality notification unit 23 to execute an abnormality notification. Furthermore, the control unit 24 transmits an instruction to the other slave devices 2 registered in the configuration list to execute an abnormality notification.

[0032] Therefore, according to this embodiment, it is possible to configure a network device 2N and a network system 100 using the same, which make it possible to easily identify the extent of the influence of the slave device 2 in which an abnormality has occurred, even if the abnormality occurs in the slave device 2.

[0033] §2 Configuration example <Network System> In the example of Fig. 1, the network system 100 of the present embodiment includes a master device 1, a plurality of slave devices 2 connected to the master device 1 via communication devices (communication hubs) 5A and 5B, and an information processing device 3 and a display device 4 connected to the master device 1 via the communication device 5A. In the network system 100 of the present embodiment, for example, a network system conforming to the ETHERNET / IP standard is used (ETHERNET: registered trademark). In the network system 100 of the present embodiment, for example, the master device 1, the slave devices 2, the information processing device 3, the display device 4, and the communication devices 5A and 5B are connected using communication cables as illustrated in Fig. 1, and communication is performed via the communication cables.

[0034] The master device 1 includes, for example, a PLC (Programmable Logic Controller). The master device 1 is configured to control each of the multiple slave devices 2 by operating according to a predetermined program that can be set by an information processing device 3 or the like.

[0035] For example, four slave devices 2A, 2B, 2C, and 2D are sequentially connected to communication device 5B, and four slave devices 2E, 2F, 2G, and 2H are sequentially connected to communication device 5B. Furthermore, in the slave devices 2, the slave devices are grouped into two control groups C1 and C2, for example, as surrounded by dotted lines in Fig. 1, based on a control group configuration list set by information processing device 3. That is, control group C1 includes six slave devices 2A, 2B, 2C, 2D, 2E, and 2F, and control group C2 includes two slave devices 2G and 2H.

[0036] Furthermore, in each of the control groups C1, C2, at least one slave device 2 configures the network devices 2N in the control groups C1, C2 by previously storing the configuration list from the information processing device 3. Then, in each of the control groups C1, C2, the network devices 2N are configured to monitor the occurrence of an abnormality in the slave devices 2, and to display the occurrence of an abnormality for each of the control groups C1, C2 when an abnormality occurs in the slave device 2 (details will be described later).

[0037] For example, when the network system 100 of this embodiment is applied to manufacturing equipment in a factory, it is preferable to determine the slave devices 2 to be included in the control group taking into consideration the scope of influence of a slave device 2 in which an abnormality has occurred, such as a production line unit or a production processing unit of a product included in the manufacturing equipment. In other words, in such a case, it is possible to quickly identify the slave device 2 in which an abnormality has occurred and the slave devices 2 linked to it, and further to quickly take measures against the abnormality, which makes it easy to prevent a decrease in the production efficiency of the product.

[0038] The information processing device 3 is configured using, for example, a computer (PC), and is operated by a user to control each part of the master device 1, the slave device 2, and the display device 4. In addition, the information processing device 3, in response to the user's operation, pre-sets, for example, a configuration list of the control group C1 for the slave devices 2A and 2E included in the control group C1, and sets these slave devices 2A and 2E as network devices 2N in the control group C1. In this way, in the network system 100 of this embodiment, the information processing device 3 can be appropriately operated by a user to freely change the configuration of the slave devices 2 in each control group C1, C2 and the settings of the network devices 2.

[0039] The display device 4 is configured using, for example, a liquid crystal panel or an organic EL panel having a touch panel function. The display device 4 also operates based on, for example, an HMI (Human Machine Interface) to display predetermined information and perform input operations such as instructions.

[0040] <Network devices> 2, the network device 2N of this embodiment includes a communication unit 21, an abnormality detection unit 22, an abnormality notification unit 23, a control unit 24, and a storage unit 25. The network device 2N of this embodiment monitors other slave devices 2 in the control group by communicating with the other slave devices 2 in the control group based on a configuration list of the control group stored in advance in the storage unit 25.

[0041] The communication unit 21 is a functional block that performs bidirectional communication with other devices in the network system 100. That is, the network device 2N transmits and receives data, such as inquiries and replies to the inquiries, between the other devices through the communication unit 21.

[0042] The abnormality detection unit 22 is a functional block that detects an abnormality that occurs in the network device 2N. Specifically, the abnormality detection unit 22 detects, for example, an abnormality in the operation of the network device 2N itself or an abnormality in the operation of a device controlled by the network device 2N. When the abnormality detection unit 22 detects an abnormality, it notifies the control unit 24 of the occurrence of the abnormality.

[0043] The abnormality notification unit 23 has, for example, an LED (Light Emitting Diode) 23L as a first light emitting element, and performs abnormality notification by lighting the LED 23L of the abnormality notification unit 23 in a predetermined abnormality pattern according to an operation instruction from the control unit 24. This allows the user to visually confirm the range of influence when an abnormality occurs in the slave device 2 (including the network device 2N) in the control group. Note that the abnormality notification unit 23 is not limited to the LED (light emitting element) 23L in any way as long as it can notify the user of an abnormality. Specifically, the abnormality notification unit 23 can be configured by, for example, a sound output unit having a speaker and emitting a predetermined beep or siren sound, an image display unit having a liquid crystal panel, an organic EL panel, or a micro LED, etc., and displaying a predetermined image, or an appropriate combination of these.

[0044] In the above description, the LED 23L is turned on to notify an abnormality, but the method of an abnormality notification by the abnormality notification unit 23 is not limited to this, and is not limited in any way as long as the LED 23L is turned on in a predetermined abnormality pattern when an abnormality occurs. For example, the LED 23L may be turned on when no abnormality occurs (normal state), and may be configured to blink when an abnormality occurs, thereby changing the light emission state or light emission cycle of the LED 23L. The method of an abnormality notification is also the same for a second light emitting element (LED) provided in the slave device 2, which will be described later.

[0045] The storage unit 25 is, for example, an auxiliary storage device such as a hard disk drive or a solid state drive, and stores various processing programs executed by the control unit 24. The storage unit 25 also stores in advance a configuration list of control groups set by the information processing device 3.

[0046] The control unit 24 is a functional block that includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), etc., and controls each component in response to information processing. The control unit 24 also performs a monitoring operation to monitor each slave device 2 in a control group that is preset in the storage unit 25.

[0047] Furthermore, when the control unit 24 receives a determination result from the abnormality detection unit 22 that an abnormality has occurred, it turns on the abnormality notification unit 23 and transmits, via the communication unit 21, an instruction to execute abnormality notification to the other slave devices 2 included in the configuration list stored in the storage unit 25. As a result, in the other slave devices 2, an LED as a second light-emitting element, for example, of the abnormality notification unit thereof turns on, thereby notifying that an abnormality has occurred in the slave device 2 (including the network device 2N) included in the control group.

[0048] Furthermore, the control unit 24 inquires of the other slave devices 2 registered in the configuration list through the communication unit 21 as to whether or not there is an abnormality, and when the other slave device 2 replies that there is an abnormality, it turns on the abnormality notification unit 23 and transmits, through the communication unit 21, an instruction to execute abnormality notification to the other slave devices 2 included in the configuration list stored in the storage unit 25. As a result, in the other slave device 2, an LED as a second light-emitting element, for example, of its abnormality notification unit turns on, thereby notifying that an abnormality has occurred in the slave device 2 (including the network device 2N) included in the control group.

[0049] Furthermore, after making an inquiry about the presence or absence of an abnormality to the other slave devices 2 registered in the configuration list through the communication unit 21, if there is another slave device 2 that does not reply to the inquiry, the control unit 24 turns on the abnormality notification unit 23 and transmits, through the communication unit 21, an instruction to execute an abnormality notification to the other slave devices 2 included in the configuration list stored in the storage unit 25. As a result, in the other slave device 2, for example, an LED as a second light-emitting element in its abnormality notification unit turns on, thereby notifying that an abnormality has occurred in the slave device 2 (including the network device 2N) included in the control group.

[0050] In this way, even if the network device 2N is unable to communicate with the other slave device 2, the network device 2N can determine that an abnormality has occurred in the other slave device 2 and easily identify the scope of the influence of the slave device 2 in which the abnormality has occurred. In other words, the network device 2 of this embodiment can determine that an abnormality has occurred and notify that an abnormality has occurred in a slave device 2 (including the network device 2N) of the control group even if a communication failure occurs in the communication cable between the other slave device 2 due to a poor connection or disconnection, or a communication failure due to noise, or a communication interruption due to replacement of the slave device 2, etc.

[0051] §3 Example of operation <Settings> First, the operation of setting the configuration list of the control group will be described with reference to Figs. 3 to 6. Fig. 3 is a flowchart showing the operation of setting the configuration list of the control group in the network system. Fig. 4 is a diagram showing a specific example of the configuration list set on the information processing device side shown in Fig. 1. Fig. 5 is a diagram showing a specific example of the configuration list set on the network device side. Fig. 6 is a diagram showing a specific example of the configuration list set on the other network device side. In the following explanation of the operation example, a case will be explained in which the configuration lists Ls1 and Ls2 are set for the slave devices 2A and 2E, respectively, among the slave devices 2 of the control group C1 shown in Fig. 1, and each of these slave devices 2A and 2E is set as a network device 2N.

[0052] First, in step S101, the information processing device 3 selects the slave devices 2 to be included in the control group C1 and the network devices 2N in the control group C1 based on a user operation, and creates a configuration list Ls shown in Fig. 4. That is, in the configuration list Ls, as shown in Fig. 4, information for identifying the slave devices 2A, 2B, 2C, 2D, 2E, and 2F included in the control group C1 (e.g., IP addresses) and information indicating that they have been selected as the network devices 2N are described in a table format.

[0053] Next, in step S102, the information processing device 3 transfers the created configuration list Ls to the slave devices 2A and 2E selected as the network device 2N. As a result, the slave device 2A stores the configuration list Ls1 shown in Fig. 5 in its storage unit 25, the slave device 2A is configured as the network device 2N, and the other slave devices 2B, 2C, 2D, 2E, and 2F of the control group C1 are set as slave devices 2 to be monitored. In addition, in this configuration list Ls1, information (e.g., IP addresses) for identifying the slave devices 2A, 2B, 2C, 2D, 2E, and 2F included in the control group C1 and information indicating the slave device itself or other devices to be monitored are described in a table format.

[0054] 6 is stored in the storage unit 25 of the slave device 2E, the slave device 2E is configured as a network device 2N, and the other slave devices 2A, 2B, 2C, 2D, and 2F of the control group C1 are set as monitored slave devices 2. In addition, in this configuration list Ls2, information (e.g., IP addresses) for identifying the slave devices 2A, 2B, 2C, 2D, 2E, and 2F included in the control group C1 and information indicating the slave device itself or other devices to be monitored are written in table format.

[0055] In this manner, in this embodiment, by setting two or more network devices 2N in the control group C1, each network device 2N can be monitored by the other network devices 2N. Even if an abnormality occurs in one network device 2N and that network device 2N is no longer able to notify the control group of the abnormality, the other network devices 2N can still notify the control group C1.

[0056] In addition to the above description, the configuration lists Ls1 and Ls2 may be set in the slave devices 2A and 2E, respectively, using the function of the HMI, that is, the touch panel function of the display device 4.

[0057] <Monitoring operation> Next, the monitoring operation of the network device 2N of this embodiment will be specifically described with reference to Fig. 7. Fig. 7 is a flowchart for explaining an example of the operation of the network device. In the following description, the operation of the slave device 2A as the network device 2N will be described as an example.

[0058] First, in step S1, the control unit 24 determines whether or not the abnormality detection unit 22 has detected an abnormality based on the presence or absence of a notification of a determination result indicating that an abnormality has occurred from the abnormality detection unit 22. If an abnormality is detected (YES in S1), the process proceeds to step S3, and otherwise (NO in S1), the process proceeds to step S2 (step S1).

[0059] In step S2, the control unit 24 determines whether or not an operation instruction for the LED 23L of the abnormality notification unit 23 has been received from another network device 2N (i.e., slave device 2E) in the control group C1. If an operation instruction has not been received (NO in S2), the process proceeds to step S6, and otherwise (YES in S2), the process proceeds to step S3 (step S2).

[0060] In step S3, the control unit 24 sets the abnormal status of the network device 2N to an abnormal state. Next, the flow proceeds to step S4. Note that the abnormal status is stored, for example, in a predetermined setting area (not shown) of the RAM provided in the control unit 24, with the abnormal state or normal state written therein.

[0061] In step S4, the control unit 24 sets the light emission status of the network device 2N to an abnormal pattern. As with the abnormal status, the light emission status is stored by writing an abnormal pattern or a normal pattern in the setting area. In other words, as with the abnormal status, the light emission status is information indicating the presence or absence of an abnormality, and the light emission status of the abnormal pattern is an example of a response (signal) indicating the presence of an abnormality.

[0062] Next, in step S5, the control unit 24 lights (operates) the LED 23L of the abnormality notification unit 23 in an abnormality pattern. Next, the flow proceeds to step S6.

[0063] In step S6, the control unit 24 determines whether or not the configuration list Ls1 is stored in the storage unit 25. If the configuration list Ls1 is not stored (NO in S6), the control unit 24 determines that the slave device 2 to be monitored has not been set and ends the monitoring operation process, otherwise (YES in S6), the control unit 24 proceeds to step S7 (step S6).

[0064] In addition, the processing procedures shown in steps S1 to S6 are similarly executed in other slave devices 2 that are not selected as network devices 2N in the control group C1, but the monitoring operation processing then ends (NO in S6).

[0065] In step S7, the control unit 24 reads out the abnormality status and the light emission status of the LED (the second light emitting element) from the other slave devices 2 registered in the configuration list Ls1 through the communication unit 21. That is, the control unit 24 of the network device 2N inquires of the other slave devices 2 in the control group C1 (including the other network devices 2N (i.e., slave device 2E)) about the presence or absence of an abnormality.

[0066] Next, in step S8, the control unit 24 determines whether or not the abnormal status and the LED light emission status have been read from the other slave devices 2. That is, the control unit 24 of the network device 2N determines whether or not there has been a reply to the above inquiry from the other slave devices 2 in the control group C1. If the abnormal status and the light emission status have been read from all the other slave devices 2 registered in the configuration list Ls1 (YES in S8), the process proceeds to step S9, and otherwise (NO in S8), the process proceeds to step S11 (step S8).

[0067] In step S9, the control unit 24 determines whether or not there has been a reply from another slave device 2 indicating that the abnormal status is an abnormal state. Furthermore, the control unit 24 also reads out the abnormal status of the own device, which is set in the setting area of ​​the RAM, and determines whether or not the abnormal status of the own device is an abnormal state. If the abnormal status of all other slave devices 2 registered in the configuration list Ls1 and the own device are not an abnormal state (NO in S9), the process proceeds to step S10, and otherwise (YES in S9), the process proceeds to step S11 (step S9).

[0068] In step S10, the control unit 24 determines whether or not there has been a reply from another slave device 2 indicating that the LED light emission status is in an abnormal pattern. Furthermore, the control unit 24 also reads out the light emission status of the own device, which is set in the setting area of ​​the RAM, and determines whether or not the light emission status of the own device is in an abnormal pattern. If all other slave devices 2 registered in the configuration list Ls1 and the light emission status of the own device are not in an abnormal pattern (NO in S10), it is determined that no abnormality has occurred in all slave devices 2 (the own device and other devices to be monitored) in the control group C1, and the monitoring operation processing is terminated; otherwise (YES in S10), the process proceeds to step S11 (step S10).

[0069] By performing the processing operations from steps S7 to S10 described above, the control unit 24 determines whether or not an abnormality has occurred in the inquired slave device 2. That is, if NO is determined in step S10, the control unit 24 determines that no abnormality has occurred in the inquired slave device 2, and if NO is determined in step S8, if YES is determined in step S9, or if YES is determined in step S10, the control unit 24 determines that an abnormality has occurred in the inquired slave device 2 (detects an abnormality in the slave device 2).

[0070] In the above explanation, the abnormality is detected by reading out the abnormality status and the light emission status in step S8. However, this embodiment is not limited to this, and is not limited in any way as long as the abnormality is detected by reading out at least one of the abnormality status and the light emission status.

[0071] In step S11, the control unit 24 transmits an instruction to execute an abnormality notification to the other slave devices 2 in the control group C1 other than the slave device 2 that detected the abnormality, via the communication unit 21. That is, the control unit 24 transmits an operation instruction to the other slave devices 2 to light (operate) their LEDs (the second light-emitting elements) in the abnormal pattern.

[0072] As described above, in the network device 2N and network system 100 of this embodiment, when an abnormality occurs in any of the slave devices 2 registered in the configuration list Ls1, all of the slave devices 2 included in the configuration list Ls1 are turned on in an abnormality pattern. As a result, in the network device 2N and network system 100 of this embodiment, even when an abnormality occurs in a slave device 2, it is possible to easily identify the extent of influence of the slave device 2 in which the abnormality occurred. Furthermore, in the network device 2N and network system 100 of this embodiment, by storing the configuration list Ls1 of the control group C1 in the storage unit 25 of the network device 2N, it is possible to easily identify the above-mentioned extent of influence (the control group C1) without changing the program in the master device 1 or the display content on the display device 4.

[0073] Also, for example, in a factory where many slave devices are used, in the case of the above-mentioned conventional example where only the slave device in which an abnormality has occurred reports the abnormality, it is difficult for the administrator (user) to find that slave device and the process to which that slave device belongs. In contrast, in this embodiment, since the scope of the effect of the slave device 2 in which an abnormality has occurred can be easily identified, when an abnormality occurs in the slave device 2, the user can be promptly notified of the slave device 2 and the process to which that slave device 2 belongs, and the abnormality can also be dealt with promptly, preventing a decrease in factory productivity.

[0074] In addition, in this embodiment, the network device 2N (slave device 2) monitors the occurrence of an abnormality within the control group, so that part of the processing of the master device 1 can be performed by the network device 2N, thereby distributing the processing of the master device 1. Furthermore, in this embodiment, the processing load of the master device 1 does not increase, and there is no need to increase the performance or cost of the master device 1.

[0075] [Embodiment 2] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals are given to members having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0076] The main difference between this embodiment and the above embodiments is that the control unit 24 changes at least one of the light emission state, light emission color, and light emission period of the LED (first light-emitting element) 23L of the abnormality notification unit 23 between a case where the abnormality detection unit 22 detects an abnormality and a case where the abnormality is not detected.

[0077] In the network device 2N of this embodiment, for example, the LED 23L of the abnormality notification unit 23 emits light of two different colors, for example, green light and red light. Moreover, this LED 23L performs a green blinking operation in accordance with a first abnormality notification instruction from the control unit 24. Moreover, the LED 23L performs a red blinking operation in accordance with a second abnormality notification instruction different from the first abnormality notification from the control unit 24. Moreover, in the case of this LED 23L, when no abnormality occurs in any of the slave devices 2 in the control group C1, for example, the light emission state is turned off.

[0078] The control unit 24 transmits, to the slave devices 2 other than the one that responded to the inquiry that there is an abnormality, an instruction to execute the first abnormality notification, indicating that an abnormality has occurred in the slave device 2 other than the slave device 2, via the communication unit 21. As a result, the LED (second light-emitting element) of the abnormality notification unit of the slave device 2 that is the target of the instruction flashes in green.

[0079] Next, the operation of the network device 2N of this embodiment will be specifically described with reference to Fig. 8. Fig. 8 is a flowchart for explaining an example of the operation of the network device according to the second embodiment of the present disclosure. Note that in the following description, similar to the first embodiment, the operation of the slave device 2A as the network device 2N will be described as an example.

[0080] In step S21, the control unit 24 determines whether or not the abnormality detection unit 22 has detected an abnormality based on the presence or absence of a notification of a determination result indicating that an abnormality has occurred from the abnormality detection unit 22. If an abnormality is detected (YES in S21), the control unit 24 proceeds to step S25, and otherwise (NO in S21), the control unit 24 proceeds to step S22 (step S21).

[0081] Next, in step S22, the control unit 24 determines whether or not an operation instruction (first abnormality notification instruction) for the LED 23L of the abnormality notification unit 23 has been received from another network device 2N (i.e., slave device 2E) in the control group C1. If an operation instruction has not been received (NO in S22), the process proceeds to step S28, and otherwise (YES in S22), the process proceeds to step S23 (step S22).

[0082] In step S23, the control unit 24 sets the light emission status of the network device 2N to the first operating state (green flashing operating state).

[0083] In step S24, the control unit 24 instructs the abnormality notification unit 23 to issue a first abnormality notification, and the LED 23L in the abnormality notification unit 23 operates in the first operating state. That is, the LED 23L flashes in green.

[0084] In step S25, the control unit 24 sets the abnormal status of the network device 2N to an abnormal state.

[0085] In step S26, the control unit 24 sets the light emission status of the network device 2N to the second operating state (red flashing operating state).

[0086] In step S27, the control unit 24 instructs the abnormality notification unit 23 to issue a second abnormality notification, and the LED 23L in the abnormality notification unit 23 operates in the second operating state. That is, the LED 23L flashes in red.

[0087] In step S28, the control unit 24 determines whether or not the configuration list Ls1 is stored in the storage unit 25. If the configuration list Ls1 is not stored (NO in S28), the control unit 24 determines that the slave device 2 to be monitored has not been set and ends the monitoring operation process, otherwise (YES in S28), the control unit 24 proceeds to step S29 (step S28).

[0088] In addition, in the other slave devices 2 that are not selected as the network device 2N in the control group C1, the processing procedure shown in steps S21 to S28 is similarly executed, but the monitoring operation processing ends next (NO in S28). Therefore, if an abnormality occurs in the other slave device 2, the abnormality status in the other slave device 2 is set to an abnormal state, the light emission status is set to the second operating state, and the LED of the abnormality notification unit thereof flashes red.

[0089] In step S29, the control unit 24 reads out the abnormality status and the light emission status of the LED (the second light-emitting element) from the other slave devices 2 registered in the configuration list Ls1 through the communication unit 21. That is, the control unit 24 of the network device 2N inquires of the other slave devices 2 in the control group C1 (including the other network devices 2N (i.e., slave device 2E)) about the presence or absence of an abnormality.

[0090] Next, in step S30, the control unit 24 determines whether or not the abnormal status and the LED light emission status have been read from the other slave devices 2. That is, the control unit 24 of the network device 2N determines whether or not there has been a reply to the above inquiry from the other slave devices 2 in the control group C1. If the abnormal status and the light emission status have been read from all the other slave devices 2 registered in the configuration list Ls1 (YES in S30), the process proceeds to step S31, and otherwise (NO in S30), the process proceeds to step S33 (step S30).

[0091] In step S31, the control unit 24 determines whether or not there has been a reply from another slave device 2 indicating that the abnormal status is an abnormal state. Furthermore, the control unit 24 also reads out the abnormal status of the own device, which is set in the setting area of ​​the RAM, and determines whether or not the abnormal status of the own device is an abnormal state. If the abnormal status of all other slave devices 2 registered in the configuration list Ls1 and the own device are not an abnormal state (NO in S31), the process proceeds to step S32, and otherwise (YES in S31), the process proceeds to step S33.

[0092] In step S32, the control unit 24 determines whether or not there has been a reply from the other slave devices 2 indicating that the LED light emission status is in the second operating state. Furthermore, the control unit 24 also reads out the light emission status of the own device, which is set in the setting area of ​​the RAM, and determines whether or not the light emission status of the own device is in the second operating state. If all the other slave devices 2 registered in the configuration list Ls1 and the light emission status of the own device are not in the second operating state (NO in S32), it is determined that no abnormality has occurred in all the slave devices 2 (the own device and other devices to be monitored) in the control group C1, and the monitoring operation processing is terminated; otherwise (YES in S32), the process proceeds to step S33.

[0093] By performing the processing operations of steps S29 to S32 described above, the control unit 24 determines whether or not an abnormality has occurred in the inquired slave device 2. That is, if NO is determined in step S32, the control unit 24 determines that no abnormality has occurred in the inquired slave device 2, and if NO is determined in step S30, if YES is determined in step S31, or if YES is determined in step S32, the control unit 24 determines that an abnormality has occurred in the inquired slave device 2 (detects an abnormality in the slave device 2).

[0094] In step S33, the control unit 24 transmits an operation instruction to the other slave devices 2 other than the slave device 2 that detected the abnormality to operate the LED (second light-emitting element) of the abnormality notification unit in the first operation state. That is, in the other slave devices 2, the LED blinks green. As a result, in the slave device 2 that detected the abnormality, the LED of the abnormality notification unit operates in the second operation state and blinks red, and in the other slave devices 2 in the control group C1, the LED of the abnormality notification unit operates in the first operation state and blinks green.

[0095] As described above, this embodiment provides the same effects as the first embodiment.

[0096] Furthermore, in the network device 2N of this embodiment, when an abnormality occurs in any of the slave devices 2 registered in the configuration list, all slave devices 2 that are not abnormal are made to perform a first abnormality notification. Also, in the slave device 2 in which an abnormality has occurred, a second abnormality notification is performed by its abnormality notification unit. As a result, in the network device 2N and network system 100 of this embodiment, as in the first embodiment, even when an abnormality occurs in a slave device 2, the scope of influence of the slave device 2 in which the abnormality has occurred can be easily identified. Also, in the network device 2N and network system 100 of this embodiment, since the first abnormality notification and the second abnormality notification are different from each other, it is possible to more easily identify the slave device 2 in which the abnormality has occurred in the slave devices 2 in the control group.

[0097] In the above description, an example has been given of the use of an LED (first light-emitting element) 23L capable of emitting light in two colors in the abnormality notification unit 23, but this embodiment is not limited to this. For example, LEDs that emit the same light color may be used, and at least one of the light-emitting state and the light-emitting period may be made different from each other.

[0098] In the above description, the network device 2N and the slave device 2 are configured in the same way, but the present disclosure is not limited to this, and the network device 2N and the slave device 2 may be configured separately. However, the case where the network device 2N and the slave device 2 are configured in the same way is preferable in that it is easier to select and change the network device 2N in the control group.

[0099] [Software implementation example] The functional blocks of the network device 2N (particularly, the control unit 24) may be realized by a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like, or may be realized by software.

[0100] In the latter case, the control unit 24 includes a computer that executes instructions of a program, which is software that realizes each function. The computer includes, for example, one or more processors, and a computer-readable recording medium that stores the program. In the computer, the processor reads the program from the recording medium and executes it, thereby achieving the object of the present disclosure.

[0101] The processor may be, for example, a CPU (Central Processing Unit). The recording medium may be a "non-transitory tangible medium" such as a ROM (Read Only Memory), a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like. The device may further include a RAM (Random Access Memory) for expanding the program.

[0102] The program may be supplied to the computer via any transmission medium capable of transmitting the program (such as a communication network or a broadcast wave). Note that one aspect of the present invention may also be realized in the form of a data signal embedded in a carrier wave, in which the program is embodied by electronic transmission.

[0103] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present disclosure. [Explanation of symbols]

[0104] 1 Master device 2 Slave Device 2N Network Equipment 21 Communications Department 22 Anomaly detection section 23 Abnormality Notification Section 23L LED (light emitting element) 24 Control Unit 25 Memory section 100 Network Systems

Claims

1. A network device, which is a slave device used in a network system in which a master device and a plurality of slave devices controlled by the master device are connected, comprising: a communication unit for transmitting and receiving data between the slave device and the other slave device; an abnormality detection unit that detects an abnormality; an abnormality notification unit that executes an abnormality notification; a storage unit that stores in advance a configuration list of a group including the network device and at least one of the other slave devices; A control unit that controls each unit of the network device, The control unit is making an inquiry to the other slave devices registered in the configuration list via the communication unit as to whether or not there is an abnormality, and when there is a reply from the other slave devices indicating the presence of an abnormality or when the abnormality detection unit detects an abnormality, causing the abnormality notification unit to execute an abnormality notification, and transmitting an instruction to execute an abnormality notification to the other slave devices registered in the configuration list via the communication unit; The control unit further comprises: A network device that, if there is another slave device that does not respond to the inquiry, causes the abnormality notification unit to execute an abnormality notification and sends an instruction to the other slave devices registered in the configuration list via the communication unit to execute an abnormality notification.

2. The network device according to claim 1 , wherein the abnormality notification unit has a first light-emitting element, and the abnormality notification is performed by lighting up the first light-emitting element.

3. The control unit is 3 . The network device according to claim 2 , wherein at least one of a light emitting state, a light emitting color, and a light emitting cycle of the first light emitting element is made different between a case where the abnormality detection unit detects an abnormality and a case where the abnormality detection unit does not detect an abnormality.

4. The control unit is Among the other slave devices registered in the configuration list, 4. The network device according to claim 1, wherein, for the slave devices other than the slave device that has replied that there is an abnormality, the instruction is sent to execute a first abnormality notification, indicating that an abnormality has occurred in the slave device other than the slave device.

5. A network system in which a master device and a plurality of slave devices controlled by the master device are connected, A network system, comprising at least one network device according to claim 1 connected as the slave device.

6. A network system in which a master device and a plurality of slave devices controlled by the master device are connected, At least one network device according to claim 4 is connected as the slave device, As another embodiment of the slave device according to claim 4, A second light emitting element is provided, The network system is further connected to a slave device that operates to change at least one of the light emitting state, light emitting color, and light emitting period of the second light emitting element when an instruction to execute the first abnormality notification is received and when the first abnormality notification is not received.

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