Safety Controller

Abstract

To provide a mechanism for preferably displaying various pieces of information, which are received from safety input devices, using a safety controller.SOLUTION: A safety controller 3 acquires safety input signals which are received through an affinity port 9 through which one or more safety input devices are connected and from the one or more safety input devices connected through the affinity port 9, and condition information on the safety input devices. The safety controller 3 includes an MCU 23 that produces a safety output signal on the basis of the acquired safety input signals according to a safety program, and a display device 5a that displays the conditions of the safety input devices which are sources of acquisition of the condition information.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a safety controller. [Background technology]

[0002] Many industrial machines are in operation in factories that produce products (workpieces). Safety systems are essential to ensure the safety of humans from industrial machines. In general, safety systems bring industrial machines to an emergency stop when a human enters the operating area of ​​the industrial machines. For this reason, safety input devices that monitor the intrusion of objects such as humans into the operating area of ​​the industrial machines are installed in various places in the safety system. There are various types of safety input devices, such as sensors such as light curtains, scanners, and cameras that detect the intrusion of objects, and door switches that detect the opening and closing of doors. These safety input devices are connected to a safety controller that performs safety control of the safety system. The safety controller monitors the safety input signals from the safety input devices and brings the industrial machines to an emergency stop if necessary.

[0003] Thus, the safety input device is an important device for ensuring human safety in the safety system, and not only the safety input signal but also the status information related to the safety input device is very important information. For example, a light curtain uses multiple light beams to provide a light beam barrier in a specified intrusion area, and when the light beam is blocked by an object, the amount of light received decreases, so that the intrusion can be detected. Therefore, the installation positions of the light source unit and the light receiving unit are important, and in order to check whether they are optimally installed, it is necessary to monitor the amount of light received in each optical axis. This amount of light received corresponds to the above-mentioned status information, and is information that is necessary for workers to check the status of the equipment. Patent Document 1 proposes a method for visually checking and confirming the set parameters and light amount in an operator control unit such as a PC that sets parameters for a safety sensor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2009-515265 Summary of the Invention [Problem to be solved by the invention]

[0005] A safety controller is a device for executing safety control, and the interface with safety input devices was generally limited to safety ON / OFF signals. In addition, an external device, a PC, is connected to the safety sensor to check the settings and information of various parameters, and a separate PC or similar device is required to set and check the settings and information. When connecting a PC to check the settings, unintentional program rewriting is expected, and there are cases where the situation cannot be checked immediately on site. However, there is a demand for a system that allows the user to check various information related to safety input devices more easily on site. For example, when an emergency shutdown occurs in industrial equipment, it is desirable to quickly identify the cause, eliminate the danger, and restore the industrial equipment as soon as possible.

[0006] Therefore, an object of the present invention is to provide a mechanism for suitably displaying various information from a safety input device on a safety controller. [Means for solving the problem]

[0007] The present invention relates to, for example, a port including a communication terminal and for connecting one or more safety input devices; an IO connector including a pair of duplicated input terminals and for connecting one or more safety input devices; an acquisition means for acquiring a first safety input signal and status information of the safety input devices from the one or more safety input devices connected by the port and acquiring a second safety input signal from the one or more safety input devices connected by the IO connector; an execution engine for generating a safety output signal based on the first safety input signal and the second safety input signal acquired by the acquisition means in accordance with the safety program transmitted from an external device as a program generated by a user; and a WEB server unit for transmitting status information acquired by the acquisition means to a WEB client in order to display on the WEB client the status of the safety input device from which the status information is acquired. Effect of the Invention

[0008] According to the present invention, various information from a safety input device can be suitably displayed on a safety controller. [Brief description of the drawings]

[0009] [Figure 1] Diagram explaining the safety controller system [Diagram 2] Diagram explaining the safety controller and expansion modules [Diagram 3] Diagram explaining the Web server [Figure 4] Diagram explaining the detailed UI of the safety controller [Diagram 5] Diagram explaining the user interface [Figure 6] Diagram illustrating cascaded door switches [Figure 7] Diagram explaining the user interface [Figure 8] Diagram explaining the user interface [Figure 9] Diagram explaining the user interface [Figure 10] Diagram explaining the user interface [Figure 11] A flowchart showing a process for storing information from a safety input device as history information. [Figure 12] A flowchart showing a processing procedure for displaying information from a safety input device. [Figure 13] Diagram explaining the functions of the MCU in the safety controller [Figure 14] is a perspective view of the safety controller. [Figure 15] is a perspective view of the safety controller. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are necessarily essential to the invention. Two or more features among the multiple features described in the embodiments may be arbitrarily combined. In addition, the same reference numerals are given to the same or similar configurations, and duplicated descriptions are omitted. In particular, lowercase alphabets are given to distinguish multiple similar components, and when a description common to multiple components is described, the lowercase alphabets may be omitted.

[0011] <Safety Controller System> FIG. 1 shows the whole system. In this example, the safety controller system 1 has a safety controller 3, which is a main module, and expansion modules 4a and 4b. The safety controller 3 executes a safety program transferred from a PC 2, which functions as a creation support device that supports a user in creating a safety program. The safety controller 3 has a display device 5a, an operation unit 6a, a communication connector 7a, an IO connector 10a, affinity ports 9a and 9b, and the like. The PC 2 also has a display device 5b and an operation unit 6b. The communication connector 7a may be a connector for USB or a wired LAN. A communication cable from the PC 2 is connected to the communication connector 7a. The wired LAN may be industrial Ethernet (registered trademark). LAN is an abbreviation for local area network. A safety input device 11a, such as an emergency stop switch or a light curtain, is connected to the input terminal of the IO connector 10a. An industrial device, such as a robot arm, is connected as a power source (hazard source) to the output terminal of the IO connector 10a.

[0012] The affinity ports 9a and 9b are connected to safety input devices 11c to 11h having interfaces corresponding to the affinity ports 9a and 9b. Examples of the safety input devices 11 that can be connected to the affinity ports 9a and 9b include safety sensors such as light curtains, safety laser scanners, and door switches. The affinity port 9 is a port having an ON / OFF input terminal that receives a safety output signal such as an OSSD signal output from the safety input device as a safety input signal, power supply terminals such as a +24V terminal and a 0V terminal for supplying power to the safety input device, and a communication terminal for communicating with the safety input device. The ON / OFF input terminals are a pair of terminals that receive a duplicated safety output signal from the safety input device as a duplicated safety input signal, similar to the pair of duplicated input terminals included in the IO connector 10a. The affinity port 9 may have an AUX terminal instead of or in addition to the communication terminal. The AUX terminal is a terminal that receives an auxiliary signal from the safety input device 11, and receives, for example, a signal indicating the detection state of a safety sensor or a signal indicating the detection state in a warning area different from the protection area corresponding to the OSSD signal.

[0013] The safety controller 3 performs calculation processing according to a safety program on input values ​​such as a safety input signal input from the safety input device 11a, calculates an output value, and outputs the output value to the power source 12. For example, when an emergency stop switch, which is a type of safety input device 11a, is pressed down, the safety controller 3 changes the output value from ON (safe) to OFF (unsafe). This stops the power source 12. There are cases where all the safety input devices and power sources cannot be connected by only the IO connector 10a provided on the safety controller 3. In such cases, the extension modules 4a and 4b are connected to the safety controller 3.

[0014] The expansion modules 4a and 4b have IO connectors 10b and 10c, respectively, to which a safety input device 11b, a power source 12, and the like can be connected. The expansion modules 4a and 4b and the safety controller 3 communicate with each other to transfer input signals, output signals, and status information from the safety input devices. That is, the safety controller 3 generates output signals by applying a safety program to the input signals acquired from the safety input device 11a connected to itself and the safety input device 11a connected to the expansion modules 4a and 4b. Furthermore, the safety controller 3 outputs output signals generated according to the safety program to the power source 12 connected to itself or to the power source 12 connected to the expansion modules 4a and 4b. The expansion modules 4a and 4b may also have affinity ports 9. Safety input devices and safety output devices can also be connected to the affinity ports 9 of the expansion modules 4a and 4b.

[0015] The safety controller 3 has an IO connector 10a on the front side, is attached to a mounting fixture on the rear side, and other modules are arranged on the side. The affinity port 9 may be provided on the front side of the safety controller 3 from the viewpoint of ease of access. In addition, the display device 5a, the operation unit 6a, the communication connector 7a, the IO connector 10a, etc. may be provided on the front side of the safety controller 3, and the affinity port 9 may be provided on the upper or lower side of the safety controller 3 from the viewpoint of the size of the safety controller 3. The safety controller 3 may further have a remote IO port for communicating with a remote IO. The remote IO port is provided, for example, on the upper or lower side of the safety controller 3, on a different surface from the affinity port 9.

[0016] The safety controller 3 and the extension module 4 are connected via an internal bus, and the safety controller 3 communicates with the extension module 4 via the internal bus to acquire a safety input signal from the safety input device 11 connected to the IO connectors 10b and 10c. The safety controller 3 also acquires a safety input signal from the safety input device 11 and acquires additional information from the safety input device 11 while supplying power to the safety input device 11 via the affinity port 9. That is, the safety controller 3 has a first acquisition path for acquiring a safety input signal (input value) from the safety input device 11b connected to the IO connector 10b of the extension module 4 via the internal bus, and a second acquisition path for acquiring a safety input signal (input value) from the safety input devices 11c to 11h via the affinity port 9. In addition, when the safety controller 3 has a remote IO port, the safety controller 3 has a third acquisition path via the remote IO port. The safety controller 3 also has a function of a safety controller and a function of a sensor controller. The function of the safety controller is to generate a safety output signal (output value) according to a safety program using the safety input signal (input value) acquired via the first and second acquisition paths, and the function of the sensor controller is to display or record additional information from the safety input devices 11c to 11h such as safety sensors, or to control the safety input devices 11c to 11h such as safety sensors. As shown in FIG. 1, the safety input devices 11c to 11e and 11f to 11h such as safety sensors can be connected in series. By connecting in series, power is supplied to each safety input device 11 from the safety controller 3 side, and a logical operation is performed to combine the safety output signals of each safety input device 11 by the safety input devices 11c and 11h on the safety controller 3 side, so that a pair of safety output signals can be input to the safety controller 3 as a pair of safety input signals. In addition, each safety input device 11 connected in series communicates additional information possessed by each safety input device 11 with the safety controller 3. A safety sensor generally determines whether to output ON or OFF as a safety output signal based on the detection results within a protected area to be monitored, predetermined determination conditions, and error detection results.The additional information includes, for example, the results of detection within a protected area by a safety sensor, the results of error detection, and the like, and helps to clarify the cause why the safety output signal became an OFF signal.

[0017] <Safety controller and expansion module hardware> As shown in FIG. 2, the controller 20a of the safety controller 3 has two MCUs (micro controller units) 23a and 24a and a memory 25a. The controller 20a stores the safety program received from the PC 2 in the memory 25a. The MCUs (micro controller units) are duplicated to improve reliability. The MCUs 23a and 24a each execute the safety program held in the memory 25a. The MCUs 23a and 24a generate output signals based on the input signal of the safety input device 11 via the affinity port 9 and the safety input IF 21a and the input signal input from the expansion module 4 via the bus IF 26a, and output the output signals to the safety output IF 22a and the expansion module 4. For example, if both the MCUs 23a and 24a output an ON signal, the safety output IF 22a outputs an ON signal. If one or both of the MCUs 23a and 24a output an OFF signal, the safety output IF 22a outputs an OFF signal. In this way, the controller 20a communicates with the expansion module 4 via the bus IF 26a to receive input signals and transmit output signals. The communication IF 27a communicates with other devices via the communication connector 7a. Circuits related to the OSSD signals, power supply, and communication of the affinity port 9 may be included in the communication IF 27a or may be independent as separate circuits.

[0018] Examples of safety input devices include safety laser scanners, light curtains, door switches, etc. Safety input devices generally meet safety standards, and the output of the safety input device is duplicated. When a signal mismatch occurs due to the duplication, the safety controller or the sensor itself can detect the failure of the sensor.

[0019] In addition to the safety program received from the PC 2, the memory 25a also stores, as history information, the signal values ​​and status information of the input signals input from the safety input devices 11a and 11b via the safety input IF 21a. The MCUs 23a and 24a temporarily store information acquired from each safety input device in a temporary storage area provided in the memory 25a, and when a predetermined condition is satisfied, the MCUs 23a and 24a formally store the information in the memory 25a as history information. On the other hand, when a predetermined time has elapsed since the information was temporarily stored without satisfying the predetermined condition, the MCUs 23a and 24a delete the information. This makes it possible to prevent the exhaustion of memory resources due to information from the safety input devices. The above-mentioned predetermined condition is, for example, when the logic of the safety output signal changes, and the MCUs 23a and 24a store information before and after the change point in the memory 25a as history information. This allows the worker to check, for example, the status information of the safety input devices before and after the power source 12 is stopped in an emergency, and to efficiently obtain useful information.

[0020] The controller 20b of the extension module 4a has two MCUs 23b and 24b and a memory 25b. The MCUs (microcontroller units) are duplicated to improve reliability. The MCUs 23b and 24b each execute a control program stored in the memory 25b. When the controller 20b receives an input signal from the safety input device 11 via the safety input IF 21b, the controller 20b transmits the input signal to the safety controller 3 via the bus IF 26b. When the controller 20b receives an output signal from the safety controller 3 via the bus IF 26b, the controller 20b outputs the output signal to the power source 12 or the like via the safety output IF 22b. Similarly to the memory 25a, the memory 25b stores information about the safety input device connected to the extension module 4. The storage method is also the same as that of the safety controller 3 described above. Note that, when the memory 25b of the extension module 4 has a smaller memory size than the memory 25a of the safety controller 3, only a temporary storage area may be provided to notify the safety controller 3 of information before and after the above-mentioned change point. In that case, the safety controller 3 also stores history information about the safety input device connected to the extension module 4. Alternatively, the safety controller 3 may also notify an external device of history information and store it in the external device. Furthermore, each device may store history information to the extent possible, and when memory shortage occurs, the history information may be stored in another device. A communication IF 27a may be provided as a circuit for the affinity port 9.

[0021] The controller 20c of the expansion module 4b has two MCUs 23c and 24c and a memory 25c. The MCUs (microcontroller units) are duplicated to improve reliability. The MCUs 23c and 24c each execute a control program stored in the memory 25c. When the controller 20c receives an input signal from the safety input device 11 via the safety input IF 21c, it transmits the input signal to the safety controller 3 via the bus IF 26c. When the controller 20c receives an output signal from the safety controller 3 via the bus IF 26c, it outputs the output signal to the power source 12 or the like via the safety output IF 22c. A communication IF 27a may be provided as a circuit for the affinity port 9.

[0022] <PCのハードウエア> As shown in Fig. 3, the PC 2 includes a CPU 13, a display device 5b, an operation unit 6b, a storage device 15, and a communication IF 27b. The display device 5b, the operation unit 6b, the storage device 15, and the communication IF 27b are each electrically connected to the CPU 13. The storage device 15 includes a RAM, a ROM, an HDD, and an SSD, and may further include a removable memory card. CPU is an abbreviation for central processing unit. ROM is an abbreviation for read-only memory. RAM is an abbreviation for random access memory. HDD is an abbreviation for hard disk drive. SSD is an abbreviation for solid state drive.

[0023] The storage device 15 stores the editing program 16 and the history information 17. These pieces of information can be updated later. The user of the PC 2 causes the CPU 13 to execute the editing program 16 stored in the storage device 15, edits the safety program and the setting information through the operation unit 6b, and transfers them to the safety controller 3. The setting information includes identification information of the extension module 4 connected to the safety controller 3, and identification information (terminal assignment information) of the safety input device 11 and the power source 12 connected to each input terminal and each output terminal provided on the affinity ports 9a, 9b and the IO connectors 10a to 10c. The history information 17 is the same as the information from the safety input device stored in the memories 25a and 25b described above, and is information obtained from the safety controller 3. The CPU 13 may present the user with history information indicating the state of each safety input device, etc., based on the history information 17.

[0024] The PC 2 can also function as a Web client of the safety controller 3. In this case, the screen information generated by the safety controller 3 is acquired via the Web through the communication line 18 of the external network, and displayed on the display device 5b. This screen information includes the same contents as the history information displayed by the safety controller 3, which will be described later. In other words, the safety controller 3 functions as a Web server, and can provide a screen showing the status of sensors, etc., based on various information acquired from safety input devices, to an external device such as the PC 2, which is a Web client. This makes it possible to check the status of the safety controller system 1 remotely.

[0025] <Safety Controller Details UI> FIG. 4 shows a detailed user interface (UI) of the safety controller 3. The same components as those already shown in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. The safety controller 3 includes a display device 5a and an operation unit 6a in a part of its housing (for example, the front of the housing) as a user interface. The operation unit 6a is provided with keys 44a to 44d. A touch panel type liquid crystal display (LCD) may be adopted for the display device 5a, and in that case, the operation unit is also provided integrally with the display device 5a. 45a indicates a USB connector, and 45b indicates a LAN connector. In addition, various screens displayed on the display device 5a described below are displayed and controlled by the MCU 23a or 24a, but may be controlled by either of the duplicated MCUs. Here, a case where the MCU 23a controls will be described as an example. The program that performs the control is a program different from the safety program, and may be a program previously incorporated in the MCU, or may be a program stored in the memory 25a. As described with reference to FIG. 1, the safety controller 3 is provided with a plurality of affinity ports 9a, 9b, etc., for example, on the upper part of the housing thereof.

[0026] The display device 5a shown in FIG. 4 displays a top screen, which is a basic configuration screen. The top screen is a screen that is normally displayed while the safety controller system 1 is in operation. The top screen is provided with various display areas 41 to 43c, 47. The MCU 23a controls the display of each display area 41 to 47 according to the system status. The display area 41 displays the state of the safety output. The display area 42 displays the execution state of the safety program, the login state, the set value, etc. The display areas 43a to 43c display the signal states (ON, OFF) of the safety input and safety output connected to the ports of the safety controller 3. The display area 47 displays the functions that are performed when the keys 44a to 44c are operated. Note that these displays are merely examples and are not intended to limit the present invention. In the example of FIG. 4, it is shown that when the key 44a is operated, the screen transitions to a detailed screen of the safety output. When the key 44b is operated, the screen transitions to a detailed screen of each unit connected to the safety controller 3. When the key 44c is operated, the screen transitions to a menu screen. The key 44d is a BACK key, and when the MCU 23a accepts the operation of the key 44d, it returns the display to the previously displayed screen.

[0027] In addition, the top screen displays the signal values ​​(ON, OFF) of the devices connected to the safety controller 3. However, each device has status information in addition to the signal value. For example, a light curtain, which is a safety input device, has information on the amount of light received, and a door switch has a lock state and a door open / close state. These pieces of information can be useful for clarifying the cause of an emergency stop of the system, for example. Therefore, the safety controller 3 according to this embodiment also displays these pieces of information. The display may output the real-time device status or the past device status. The following describes the status output displayed on the display unit of the safety controller 3. As will be described later, the display described below may be transmitted to the safety input device that acquired the information and displayed, or the safety controller 3 may function as a Web server and provide the generated screen information to a Web client such as the PC 2 and display it.

[0028] <Safety input device status output> (Light curtain status output screen) FIG. 5 shows a status output screen 50 of a light curtain, which is a safety input device.

[0029] A light curtain monitors a protected area using multiple optical axes and has multiple pairs of light-emitting elements and light-receiving elements corresponding to the multiple optical axes. The paired light-emitting elements and light-receiving elements are arranged opposite each other and detect objects in the protected area by detecting the blocking of the optical axis by an object, as well as errors in the self-circuitry, etc. Light curtains are safety sensors that generate a safety output signal based on the object detection results and error detection results.

[0030] The additional information of the light curtain includes, for example, at least one of the following information: information on the detection of an object in the protected area, information indicating the ON / OFF status of each optical axis of the light curtain, information indicating the amount of light of each optical axis of the light curtain, information indicating an error detected in the light curtain, information indicating the mute state of the light curtain, and information indicating the light curtain waiting to be reset.

[0031] The safety controller 3 can obtain not only information related to its own safety control, but also information related to the generation of a safety output signal from the safety input device 11 and information related to the protection area as additional information.

[0032] On the top screen shown in Fig. 4, for example, when the key 44b is operated to transition to an item screen for each unit and a specific unit, here the light curtain connected to port A, is selected, the MCU 23a displays a status output screen 50 on the display device 5a. The MCU 23a generates the screen of the status output screen 50 according to the safety input signal acquired from the safety input device 11b and the amount of received light, which is status information. Fig. 5(a) to Fig. 5(c) respectively show changes in the amount of received light on multiple optical axes of the light sensor.

[0033] The status output screen 50 includes at least displays 51a to 51c, 52a to 52c. Displays 52a to 52c display icons indicating a plurality of light curtains connected to the safety controller 3. In the example of Fig. 5, the light curtain corresponding to display 52C is in a selected state, and the status of the light curtain is displayed and output on displays 51a to 51c. When keys 44a and 44b corresponding to displays 53a and 53b are operated, the icon of another light curtain can be selected, and the MCU 23a displays the corresponding status output on displays 51a to 51c.

[0034] The displays 51a to 51c show the amount of light received in each optical axis of the selected light curtain in a gauge (bar graph). 54 shows a threshold for issuing a warning, and 55 shows a threshold for controlling the safety output to OFF. When the amount of light received in any optical axis falls below the threshold 54, the MCU 23a displays a warning on the display device 5a, and when the amount of light received in any optical axis falls below the threshold 55, the MCU 23a controls the safety output to OFF. The gauges displayed corresponding to each optical axis can be displayed as a ratio with the maximum amount of light received being 100% and a state where no light is received being 0%. The display 51a in FIG. 5(a) shows that the amount of light received in all optical axes is 100%, indicating a state where the light curtain is operating normally and is not blocked by an intruder or the like. The display 51b in FIG. 5(b) shows that the amount of light received in each optical axis is reduced compared to FIG. 5(a). However, even in the state of FIG. 5(b), the safety controller system 1 can ensure safety, and there is no particular problem. Display 51c in FIG. 5(c) indicates that the two gauges, as indicated by 56, are below threshold value 54. When the gauges fall below threshold value 54, the gauges are highlighted to warn an operator or the like. Furthermore, MCU 23a may notify the user by using a pop-up screen, an alarm sound, or the like. In this case, MCU 23a functions as a notification means.

[0035] In the above-mentioned examples of Fig. 5(a) to Fig. 5(c), the MCU 23a outputs the state of the light curtain based on information acquired in real time from the light curtain. However, the present invention is not limited to this, and the MCU 23a can also display a state output screen based on history information related to the light curtain stored in the memory 25a. In this case, the MCU 23a can acquire the history information from the memory 25a and output the state of the light curtain before and after the safety output is switched to OFF. In addition, the time axis of the history information can be advanced or retroactively moved in accordance with the user's operation. Details of the history information will be described later.

[0036] (Door switch status output screen) Figure 6 shows multiple door switches (DS), which are safety input devices, connected in cascade.

[0037] The door switch is a safety sensor in which an actuator having a transponder and a detector for detecting the distance from the transponder are installed at positions facing each other at points that move relatively as the door is opened or closed, and the detector detects the open / closed state of the door based on the distance to the transponder and detects errors in the self-circuit, etc., and generates a safety output signal based on the detection results of the door open / closed state and the error detection results. The door switch may also have a locking mechanism that prevents the door from being opened, and the door switch controls the locked state and the unlocked state by electrically controlling the lock pin of the locking mechanism.

[0038] The additional information of the door switch includes at least one of the following information: detection information of door opening / closing, information indicating lock control of the door switch, information indicating an error that has occurred in the door switch, information indicating a mute state of the door switch, and information indicating waiting for the door switch to lock.

[0039] The safety controller 3 can obtain not only information related to its own safety control, but also information related to the generation of a safety output signal from the safety input device 11 and information related to door opening and closing as additional information.

[0040] In FIG. 6, it is assumed that these cascaded door switches 61-66 are connected to port B of the affinity port 9 of the safety controller. The door switches 61, 64-66 are non-contact type door switches that detect the opening and closing of the door with the main body and actuator parts in a non-contact state, and the door switches 62 and 63 are lock type door switches in which two members are mechanically fitted together. These multiple types of door switches are cascaded by a signal line 67, and are finally connected to the affinity port (here, port B) of the safety controller 3. Therefore, the MCU 23a can acquire the signal values ​​and state information of the multiple door switches via port B.

[0041] Fig. 7 shows a status output screen 70 of the cascaded door switches shown in Fig. 6. When, for example, the key 44b is operated on the top screen shown in Fig. 4 to transition to an item screen for each unit and a specific unit, here the door switch connected to port B, is selected, the MCU 23a displays the status output screen 70 on the display device 5a. The MCU 23a generates the screen of the status output screen 70 according to the safety input signal acquired from the safety input device 11b and the open / closed state and locked state, which are the status information. Figs. 7(a) to 7(c) respectively show changes in the locked state and open / closed state of the doors monitored by multiple door switches.

[0042] The status output screen 70 includes at least displays 71 to 75b. Display 71 displays items when the key 44b is operated to transition to the item screen of each unit, and FIG. 7 shows a state in which the item of port B is selected. When the keys 44a and 44b corresponding to displays 75a and 75b are operated, other items can be selected, and the MCU 23a displays the corresponding status output. For example, when the item of port A is selected, the above-mentioned status output screen 50 of the light curtain is displayed in this example. Since multiple door switches are connected to port B in cascade connection as described above, the status of all the door switches is displayed in display 72. Display 73 shows icons corresponding to each door switch. For example, "1" to "6" displayed in the icon correspond to door switches 61 to 66, respectively.

[0043] The display 74a shown in FIG. 7(a) is an icon indicating the locked state of the lock-type door switches 62, 63, and indicates a locked state. On the other hand, the display 74b shown in FIG. 7(b) is an icon indicating an unlocked state. Also, as shown in 76 and 77 in FIG. 7(c), the icons "3" and "6" indicate that the doors are in an open state. Here, the icons are displayed in a shaded manner, but any method of highlighting may be used. For example, the icons may be displayed in a shaded manner in a color different from other icons indicating a closed state, the icon itself may be displayed in a flashing manner, or an icon that calls the user's attention may be superimposed on the icon.

[0044] In this way, the safety controller 3 according to this embodiment can acquire status information in addition to the safety input signal from the door switch and display it on its own display unit. Here, the MCU 23a outputs the state of the door switch, that is, the locked state or the open / closed state, based on the information acquired in real time from the door switch. However, the present invention is not limited to this, and the MCU 23a can also display a status output screen based on the history information related to the door switch stored in the memory 25a. In this case, the MCU 23a can acquire the history information from the memory 25a and output the state of the door switch before and after the safety output is switched to OFF. Also, the time axis of the history information can be advanced or retroactively moved in accordance with the user's operation. Details of the history information will be described later.

[0045] As described above, the safety controller 3 according to the present embodiment generates and displays a status output screen appropriate for the type of the safety input device. That is, the safety controller 3 determines the type of the safety input device based on information acquired from the safety input device, and generates a display screen according to the type. For example, the safety controller 3 may determine the type based on the identification information of the safety input device. Note that in the present embodiment, display examples related to a light curtain and a door switch have been described, but display screens can also be generated for other safety input devices, such as safety laser scanners and safety 3D cameras, according to their types. Furthermore, regardless of the status output of the safety input device, for example, a description related to the display of a safety sensor or information on a setting device such as a mode selector may be displayed.

[0046] Here, a brief description will be given of the status output screen of a safety scanner such as a safety laser scanner. The safety scanner is a safety sensor that detects an object in a predefined protected area based on the reflected light received from the object by scanning the protected area with a laser beam, and detects errors in the self-circuit, etc., and generates a safety output signal based on the object detection result and the error detection result. The additional information of the safety scanner includes at least one of the following information: detection information of an object in the protected area, information indicating the ON / OFF of each optical axis, information indicating the distance or light amount of each optical axis of the safety scanner, information indicating an error that has occurred in the safety scanner, information indicating the mute state of the safety scanner, information indicating the reset release waiting of the safety scanner, and image information acquired by a camera provided in the safety scanner. The safety controller 3 can acquire not only information related to its own safety control, but also information related to the generation of a safety output signal from the safety input device 11 and information related to the protected area as additional information.

[0047] The safety scanner may have various configurations, and may be configured to include, for example, a measurement unit and a camera. The measurement unit contains a rotating optical system that emits detection light in a horizontal direction and scans the detection light along a horizontal scan plane. For example, a laser light having a wavelength in the infrared region is used as the detection light. The detection light is repeatedly scanned at a certain scan period. When an object is detected by the measurement unit, distance information to the object can be obtained. Each camera is an imaging device that captures a protected area and generates a camera image as a monitoring image. A plurality of cameras may be provided, and in that case, the cameras are arranged with different orientations. Since the camera is arranged above the scan plane of the measurement unit, a camera image overlooking the scan plane can be obtained. Therefore, the information from the safety scanner includes an operating state, distance measurement information, camera images, setting data, event history, etc. Using this information, a camera image or a scan image when an intrusion is detected can be displayed as a status output screen of the safety scanner. If the display device 5a of the safety controller 3 has the capability of displaying two-dimensional images, the above-mentioned status output screen can be displayed, but even if not, information may be output to an external device so that a richer status output screen can be displayed on the external device. In this case, the safety controller 3 functions as a Web server. The Web server function will be described in detail later.

[0048] (Status display) 8(a) to 8(c) show various error screens displayed on the display device 5a when an error occurs. Here, an error display will be described as an example of a state display, but a state indicating a normal state may be displayed before an error occurs. When indicating a normal state, the normal state may be displayed on the screen, or may be displayed by lighting an LED lamp or the like. FIG. 8(a) shows an error screen that is displayed when, for example, the key 44b is operated on the top screen shown in FIG. 4 when an error occurs, transition is made to an item screen of each unit, and further, a specific unit, here, a light curtain connected to port A, is selected. Alternatively, it may be displayed when the key 44c corresponding to the menu key is operated from the top screen shown in FIG. 4, and history information is selected from a menu screen not shown. A display 81 shows each item, and indicates that port A is currently selected. The MCU 23a displays a mark 84 superimposed on an item at which an error occurs among a plurality of items. Here, it is shown that an error has occurred in port A, and an error has occurred in the main module accordingly. A display 82 shows a device connected to port A, and also displays a mark 85 indicating that an error has occurred. Display 83 indicates the content of the error, and in this case indicates that a communication error has occurred in one of the multiple light curtains. Therefore, the user can easily identify the cause of the error by checking the parts related to the content of the error, for example, whether there is a problem with the communication connection. Furthermore, by the user selecting display 82 or display 83, a light curtain status output screen such as that described using Figures 5(a) to 5(c) can be displayed. In this case, the MCU 23a may acquire and display historical information before and after the error occurred, rather than displaying real-time information.

[0049] Figures 8(b) and 8(c) show pop-up displays 86, 88 which are displayed when an error occurs while the top screen shown in Figure 4 is being displayed. Display 86 in Figure 8(b) indicates that a connection error has occurred in the door switch connected to port B. Display 86a also shows a detailed error code, allowing the worker to understand the details of the error. Display 88 in Figure 8(c) indicates an error that occurs when the configurations of multiple door switches cascaded to port B do not match. Display 88a also shows a detailed error code. Display 87 in Figures 8(b) and 8(c) indicates that a function for stopping the warning is assigned to key 44a.

[0050] (Displaying change points using history information) 9 and 10 show a change point display screen that displays history information before and after the safety output is changed to OFF. The change point display screen is a screen that displays the state of the safety output when, for example, the key 44a is operated on the top screen shown in FIG. 4. Alternatively, the change point display screen can be displayed on the display device 5a when the key 44c corresponding to the menu key is operated on the top screen shown in FIG. 4 and history information is selected from a menu screen (not shown). Note that the screen examples shown in FIG. 9 and FIG. 10 are illustrated to explain that the current state of each safety input signal related to the change in the safety output signal and the state before and after the change point can be displayed. Therefore, those signal values ​​are merely examples and do not strictly reproduce the combination of signal values ​​that may occur when the safety system is operated.

[0051] Screen 90 in Fig. 9(a) is a selection screen for selecting the target output to be displayed on the change point display screen. Display 91 displays each safety output in a list, and display 91a indicates the status of the safety output of the corresponding item as ON or OFF. Selection screen 90 shows that safety output Main:0-1 has been turned OFF. Display 92a indicates that the selection status of the item will move downward when the corresponding key 44a is operated. In the example of Fig. 9(a), it shows that item Main:0-1 is in the selected state. Display 92b transitions to a details screen of the selected item when the corresponding key 44c is operated.

[0052] A screen 94 in FIG. 9(b) is a screen to which the screen transitions when the key 44c in FIG. 9(a) is operated. The screen 94 shows the current signal state of each port (signal from the related input block). The display 93a shows the current signal state of each port as ON or OFF. Here, it is clear that Main:6 is OFF, and the cause of the safety output being OFF can be confirmed. A screen 95 in FIG. 9(c) is a screen to which the screen transitions when an arbitrary operation is performed while the screen 94 in FIG. 9(b) is displayed, and shows the state of each safety input at the time when the safety output (Main:0-1) is OFF. The MCU 23a can display the screen by, for example, referring to history information stored in the memory 25a. The arbitrary operation may be an operation on any of the keys 44a to 44c, or an operation on another key not shown. In addition to the screen 94, the screen 95 includes a display 93b from the history information. This shows the timing when the safety output (Main: 0-1) turned OFF, and as shown in the figure, expresses the state in which the signal switches from ON to OFF. By performing any operation here, the time axis of the history information can be moved back or forward. Display 96 shows that the output block of the safety output is currently waiting for reset release.

[0053] 10(a) and 10(c) show change point display screens when the safety output is turned OFF by an OFF signal from the door switch. The same components as those in the screens in FIG. 9 are given the same numbers and will not be described. A screen 100 in FIG. 10(a) is a change point display screen when the safety output is turned OFF by an OFF signal from the door switch connected to port B. A display 101a indicates the current signal state of each port as ON or OFF. A display 101b indicates the signal change in each port at the timing when the safety output is turned OFF. Furthermore, a screen 103 in FIG. 10(b) is a screen showing the cause of the door switch being turned OFF. The MCU 23a displays, for example, that door No. 0.4 is open, as shown in a display 102, based on the state information included in the history information stored in the memory 25a.

[0054] 10(c) and 10(d) show change point display screens when the safety output is turned off by an OFF signal from the light curtain. The same components as those in the screens in FIG. 9 are given the same numbers and will not be described. A screen 107 in FIG. 10(c) is a change point display screen when the safety output is turned off by an OFF signal from the light curtain connected to port A. A display 104a indicates the current signal state of each port as ON or OFF. A display 104b indicates the signal change in each port at the timing when the safety output is turned off. Furthermore, a screen 108 in FIG. 10(d) is a screen showing the cause of the light curtain being turned off. The MCU 23a displays, for example, that an error has been detected in the 11th optical axis of the light curtain, as shown in a display 106, based on the status information included in the history information stored in the memory 25a.

[0055] <Flowchart> 11 is a flowchart showing the processing procedure when information from a safety input device connected via the affinity port 9 is stored as history information. The processing described below is realized by the MCU 23a executing a program stored in the memory 25a. Note that processing for one safety input device will be described here. Therefore, the following processing is executed for each connected safety input device. For the safety input devices connected to the extension module 4, the extension module 4 may process them in the same way, or the safety controller 3 may process them all at once.

[0056] In S1, the MCU 23a acquires a signal value and status information from a safety input device connected to the safety controller 3 via the affinity port 9. The acquisition is performed periodically when the safety controller system 1 is in operation. Next, in S2, the MCU 23a temporarily stores the signal value and status information acquired from the safety input device together with time information in the memory 25a. Here, the memory for temporary storage does not have to be the memory 25a, and may be a separately provided memory. As described above, the processes of S1 and S2 are performed periodically.

[0057] Next, in S3, the MCU 23a judges whether the signal logic has changed. The signal here basically indicates the logic of a specified safety output signal. If there is sufficient memory capacity, the condition may be whether there has been a change in the logic of the safety input signal in addition to the safety output signal. If there has been a change in the signal logic, proceed to S4, and if not, proceed to S5.

[0058] In S4, since there is a change in the signal of the safety output, the MCU 23a associates the information temporarily stored in S2 before and after the change point (timing) with the signal value and state information as history information and stores it in the memory 25a, and ends the process. Meanwhile, since there is no change in the judgment timing of S3, the MCU 23a deletes the signal and state information temporarily stored in S2 a predetermined time ago as unnecessary data and ends the process. The above-mentioned predetermined time can be arbitrarily changed according to the memory capacity. Also, the MCU 23a judges whether or not the information was stored a predetermined time ago by using the time information stored together with the signal value and state information in S2. In this way, by leaving the information before and after the change point as history information, it is possible to store information of high importance while effectively utilizing memory resources. Note that here, an example of storing in the memory 25a has been described, but it may be stored in the memory 25b of the extension module 4, or may be transmitted to an external device and stored. Storing in these other memories may be performed when the memory of the memory 25a is exhausted.

[0059] 12 is a flowchart showing the processing procedure when acquiring information from a safety input device connected via the affinity port 9 and displaying a status output screen. The processing described below is realized by the MCU 23a executing a program stored in the memory 25a. Note that the processing described below may be started when any safety input device is connected to the affinity port 9, or when a command to display a status output screen of a safety input device connected to a specific port (here, affinity port 9) is issued according to a user input. Alternatively, the processing may be started when a specific event such as an emergency stop or an abnormal status occurs.

[0060] In S21, the MCU 23a acquires a signal value, status information, etc. from a safety input device connected via the affinity port 9. Next, in S22, the MCU 23a identifies the type of the safety input device from the information acquired in S21. For example, the MCU 23a identifies the type of the safety input device from identification information included in the acquired information. Here, the type of the safety input device indicates a door switch, a light curtain, a safety scanner, etc. The MCU 23a generates an appropriate status output screen according to the type.

[0061] Next, in S3, the MCU 23a determines the identified type. Here, it is assumed that three safety input devices, a door switch, a light curtain, and a safety scanner, are connected via the affinity port 9, but in reality, more safety input devices may be connected. Other types of safety input devices may also be connected. If it is a door switch, the process proceeds to S24, if it is a light curtain, the process proceeds to S31, and if it is a safety scanner, the process proceeds to S28.

[0062] In S24, the MCU 23a judges whether the door switch type includes a lock type. If the door switch type includes a lock type, the process proceeds to S25, and if not, the process proceeds to S26. In S25, the MCU 23a acquires the lock state of the lock type door switch among the one or more connected door switches, and proceeds to S26. In S26, the MCU 23a acquires the open / close state of the door monitored by each door switch. Note that the acquisition process in S25 and S26 may be a process of extracting predetermined information from the information acquired in S21, or may newly acquire information from a safety input device. The same applies to the subsequent acquisition processes. After that, in S27, the MCU 23a displays the state information of the door switch according to the acquired information, as described with reference to FIG. 7. Note that, if an end operation is accepted according to a user input, the display is ended.

[0063] On the other hand, if it is determined in S23 that the scanner is a safety scanner, in S28, the MCU 23a determines whether or not to newly acquire an event history from the safety scanner. The event history indicates, for example, history information of an intrusion detected by a safety sensor. The information received in S21 may include information on whether the history information is stored in the safety sensor, and in that case, the process proceeds to S29 if the history information is stored. Alternatively, the process may proceed to S29 if an instruction to acquire the event history is given according to a user input. In other cases, the process proceeds to S30. In S29, the MCU 23a acquires information on the event history from the safety scanner, and proceeds to S30. In S30, if there is an event history, the MCU 23a may display the event history and may also display the current camera image or scan image as the status information acquired in S21. On the other hand, if there is no event history, the MCU 23a displays the current camera image or scan image. The event history may be displayed in any form, for example, only the detection time information and distance measurement information may be displayed, or it may be displayed by combining it with the camera image or scan image acquired at that time. The display is terminated when an end operation is received according to user input. In the case of a safety scanner, the display contents may be changed according to the performance of the display device 5a. For example, if it is not possible to display a camera image or a scanned image, it may be possible to display only the information detected by the laser scanner.

[0064] Also, when it is determined in S23 that it is a light curtain, in S31, MCU23a extracts the values of thresholds 54 and 55 from the information acquired in S21. Subsequently, in S32, MCU23a acquires the light quantity on each optical axis of the light curtain from the information acquired in S21. Then, in S33, as described with reference to FIG. 5, MCU23a generates a state output screen regarding the light curtain and displays it on the display device 5a. Note that the display is terminated when an end operation is received according to user input. Here, an example of displaying information acquired in real time has been described, but a state output screen may be generated and displayed using the state information held in the memory 25a etc. of the safety controller 3. In that case, since the type of the device has already been specified, the processes of S21 and S22 are omitted.

[0065] <Functions of the MCU> FIG. 13 shows various functions realized by MCU23a executing the program stored in the memory 25a. The program executed here includes a program that executes the characteristic processing of the present invention described above in addition to the safety program. The program may be created by being incorporated into the safety program, or may be executed as a subroutine called from the safety program. As a functional configuration, MCU23a includes a safety control unit 1301, an acquisition unit 1302, a connection unit 1303, a Web server unit 1304, a display control unit 1305, an operation control unit 1306, and a memory control unit 1307.

[0066] The safety control unit 1301 executes the safety program stored in the memory 25a described later to perform safety control of the safety controller system 1. The acquisition unit 1302 periodically acquires the signal value and state information from the connected safety input device. Further, the acquisition unit 1302 may acquire information of the safety input device connected to the extension module 4. In this case, it will be acquired via each module. The connection unit 1303 controls the affinity port 9 and the IO connector 10a to perform connection control of each port.

[0067] The display control unit 1305 controls the display on the display device 5a as shown in the above-mentioned screen example. The display control unit 1305 may generate a screen to be displayed on the display device 5a based on information acquired in real time from the safety input device, or may generate a screen based on history information stored in the memory 25a or the like. The display control unit 1305 also determines the type of the safety input device based on the information acquired from the safety input device, and displays a status output screen according to the type. The operation control unit 1306 accepts user input via the operation unit 6a and transmits it to the display control unit 1305. The display control unit 1305 controls screen transition according to the user input. As described with reference to FIG. 11, the memory control unit 1307 controls the storage of information acquired from the safety input device by the acquisition unit 1302 in the temporary storage area 1309, or the storage of the information in the memory as formal history information. Furthermore, the memory control unit 1307 reads out history information in response to a user operation, and passes the information to the display control unit 1305.

[0068] The Web server unit 1304 controls the safety controller 3 when it functions as a Web server. In the present embodiment, an example of outputting status information to the display device 5a of the safety controller 3 has been described, but this information may be displayed on a Web client, which is an external device. In this case, the Web server unit 1304 generates a display screen from information acquired from the safety input device in real time and history information, and transmits it to the Web client. Since the safety controller 3 is a small device depending on the installation environment, the display capacity of the display device 5b is also limited. Therefore, for a Web client such as the PC 2 having a higher-performance display, a screen may be generated as a richer user interface than the above-mentioned display example. In this case, in the above-mentioned example, an example of outputting status information of a light curtain or a door switch has been described, but it is also possible to handle scanned images or camera images of a scanner or a camera (safety scanner) that requires a higher-performance display to output status information. For example, the Web server unit 1304 may transmit scanned images or camera images acquired by a scanner or a camera to the Web client and display them. Of course, the scanned images or camera images may be displayed on the display unit of the safety controller 3 according to the display capacity of the display device 5a. Furthermore, the Web server unit 1304 may be configured to return an image generated from the status information to the safety input device instead of the Web client, and output the status information from the safety input device.

[0069] The memory 25a includes a safety program 1308, a temporary storage area 1309, signal values ​​1310, and status information 1311. The safety program 1308 is edited by the PC 2, transferred, and stored, and is a program for performing safety control of the safety controller system 1. The temporary storage area 1309 is an area for temporarily storing signal values ​​and status information acquired from a safety input device. The temporary storage area may be provided in a memory different from the memory 25a. The signal values ​​1310 and status information 1311 are information stored in the temporary storage area 1309 and formally stored as history information. These pieces of information are stored in association with each other.

[0070] <Safety controller connection type> 14 and 15 are perspective views of the safety controller. As shown in FIG. 14, affinity ports 9a and 9b are provided on the top surface of the safety controller 3. A port connector 1190a provided at the tip of a cable extending from a safety input device 11 such as a safety laser scanner can be connected to the affinity ports 9a and 9b. An affinity port 9c is also provided on the top surface of the expansion module 4a. A port connector 1190d provided at the tip of a cable extending from a safety input device 11 such as a light curtain can be connected to the affinity port 9c.

[0071] A receptacle 1100 for the bus IF 26a is provided on the right side of the safety controller 3. A bus connector 1101 for the bus IF 26b is provided on the left side of the extension module 4a. By connecting the bus connector 1101a to the receptacle 1100, the bus IFs 26a and 26b are connected so as to be able to communicate with each other (internal bus connection).

[0072] Boss grooves 1102, 1103, 1104, and 1105 are provided on the right side surface of the safety controller 3. Positioning bosses 1112, 1113, 1114, and 1115 are provided on the left side surface of the extension module 4a. When the extension module 4a is connected to the safety controller 3, the bosses 1112, 1113, 1114, and 1115 are fitted into the corresponding boss grooves 1102, 1103, 1104, and 1105, respectively, and the extension module 4a is positioned relative to the safety controller 3.

[0073] The right side surface of the safety controller 3 is provided with locking grooves 1112, 1113, 1114, and 1115. The left side surface of the extension module 4a is provided with hooks 1132, 1133, 1134, and 1135. When the extension module 4a is securely fixed to the safety controller 3, the hooks 1132, 1133, 1134, and 1135 engage with the corresponding locking grooves 1122, 1123, 1124, and 1125, respectively. The hooks 1132, 1133, 1134, and 1135 are provided on the upper surface of the extension module 4a and have a lever 1130 that is movable in the forward and backward directions. In conjunction with the movement of the lever 1130, the hooks 1132, 1133, 1134, and 1135 move backwards to be locked. As the lever 1130 moves, the hooks 1132, 1133, 1134, and 1135 move forward, thereby releasing the lock.

[0074] The structure of the right side surface of the extension module 4a is the same as the structure of the right side surface of the safety controller 3, and therefore a description thereof will be omitted. The structure of the extension module 4b is the same as the structure of the extension module 4a, and therefore a description thereof will be omitted. Because a common structure is adopted for these connection surfaces, it is possible to connect the left side surface of the extension module 4b to the right side surface of the extension module 4a.

[0075] 15, a remote IO receptacle 1200 is provided on the bottom surface of the safety controller 3. A remote IO connector 1201 provided at the tip of a cable extending from a remote IO unit is connected to the remote IO receptacle 1200. The remote IO unit is a unit for connecting a safety input device and a safety output device that are located away from the safety controller 3 to the safety controller 3.

[0076] However, there is already not enough free space left on the back, front, right side, and left side of the safety controller 3 and the expansion modules 4a and 4b for their basic use as safety controllers. For example, there is a connection groove or backplane for connecting to a DIN rail on the back of the safety controller 3 and the expansion modules 4a and 4b. A display surface, I / O connectors, etc. are present on the front of the safety controller 3 and the expansion module 4. Receptacles for the bus IF 26a, etc. are arranged on the left and right sides. Therefore, there is no space to provide new ports on these sides.

[0077] Therefore, possible locations for providing the new ports are the top and bottom surfaces of the safety controller 3 and the expansion module 4. The affinity ports 9b and 9c and the remote IO receptacle 1200 for the remote IO port may be provided on the top or bottom surface of the safety controller 3 and the expansion module 4.

[0078] When the heat dissipation holes 1180, 1181, 1182, and 1183 are provided on the upper and lower surfaces of the safety controller 3 and the expansion modules 4a and 4b, respectively, only a small space is left. In this case, the arrangement space for new ports is limited. Therefore, for example, the affinity ports 9b and 9c may be arranged on the upper surface of the safety controller 3 and the expansion module 4, and a remote IO receptacle 1200 for a remote IO port may be provided on the lower surface of the safety controller 3 and the expansion module 4 (upper and lower distributed arrangement). Alternatively, the remote IO receptacle 1200 for a remote IO port may be provided on the upper surface of the safety controller 3 and the expansion module 4, and the affinity ports 9b and 9c may be provided on the lower surface of the safety controller 3 and the expansion module 4.

[0079] <Summary> [Point 1] The safety controller 3 according to the present invention includes an affinity port 9 to which one or more safety input devices are connected, and acquires safety input signals and status information of the safety input devices from the one or more safety input devices connected by the affinity port 9. The safety controller 3 also includes an MCU 23 that generates a safety output signal based on the acquired safety input signal according to a safety program, and a display device 5a that displays the status of the safety input device from which the status information is acquired based on the acquired status information. In this way, the safety controller 3 according to the present invention can display not only the signal value of the connected safety input device, but also its status information, such as the amount of light received for each optical axis of the light curtain, the lock status of the cascaded door switch, the open / close status of the door, and the scanned image by the safety scanner. Therefore, the present invention can provide a mechanism for suitably displaying various information from the safety input devices on the safety controller.

[0080] [Point 2] Furthermore, the safety controller 3 includes a memory 25a that stores information acquired from the safety input device as history information, and the display device 5a can display past information. This allows an operator to easily analyze factors that caused the safety output signal to be controlled to OFF. The memory 25a may store signals for a predetermined period before and after the safety output signal is switched. This allows the present invention to suitably hold various pieces of information from the safety input device as history information and provide important information (information before and after the safety output is switched to OFF) without increasing the memory resources of the safety controller.

[0081] [Point 3] The safety controller 3 may also transmit display information generated based on information acquired from a safety input device to the safety input device. Alternatively, the safety controller 3 may function as a Web server that transmits the display information to an external device for display. In this case, a richer user interface than that displayed on the main unit may be realized depending on the display capabilities of the external device.

[0082] [Point 4] Also, this display device 5a is characterized in that it is provided in a part of the housing of the safety controller (FIGS. 1 and 4). In this way, the status information of the safety input device can be displayed on the display section provided in the housing of the safety controller 3, and the status of each location can be easily confirmed on-site, allowing efficient repair and restoration of the system. [Point 5] Moreover, the connection means in the present invention is applied with at least an affinity port 9 to which a signal line and a communication line can be connected. The safety controller 3 acquires a safety input signal via the signal line and acquires status information via the communication line. Furthermore, the affinity port 9 may be a port to which a cable capable of supplying power can be connected in addition to the signal line and the communication line. Furthermore, the safety controller 3 may further include an IO connector 10a, which is a port to which a signal line can be connected, as another connection means for connecting one or more safety input devices (FIG. 1). The safety controller 3 acquires a safety input signal from a safety input device connected via the IO connector 10a via the signal line. The display device 5a displays the acquired safety input signal in an identifiable manner for a safety input device connected to the IO connector 10a without displaying the status of the safety input device. The signal line may be a duplicated ON / OFF cable. Thus, the safety controller 3 according to the present invention includes an affinity port 9 capable of acquiring status information of the safety input device in addition to the normal IO connector 10a, and can display richer information on a display device provided in a part of the housing of the safety controller 3.

[0083] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention.

Claims

1. A safety controller that executes a safety program, A port including a communication terminal and for connecting one or more safety input devices; an IO connector including a pair of duplicated input terminals and for connecting one or more safety input devices; an acquisition means for acquiring a first safety input signal and status information of the one or more safety input devices connected by the port, and acquiring a second safety input signal from the one or more safety input devices connected by the IO connector; an execution engine that generates a safety output signal based on the first safety input signal and the second safety input signal acquired by the acquisition means in accordance with the safety program transmitted from an external device as a user-generated program; A safety controller comprising: a WEB server unit that transmits status information acquired by the acquisition means to a WEB client in order to display the status of the safety input device from which the status information is acquired on the WEB client.

2. 2. The safety controller according to claim 1, wherein the WEB server unit transmits the status information acquired by the acquisition means to the WEB client in order to display on the WEB client a real-time status of the safety input device from which the status information is acquired.

3. The state information acquired by the acquisition means is further stored in a storage means.

3. The safety controller according to claim 1, wherein the WEB server unit transmits status information stored in the storage means to the WEB client in order to display a past status of the corresponding safety input device on the WEB client as the status of the safety input device.

4. 4. The safety controller according to claim 3, wherein the storage means stores the signal for a predetermined period before and after the logic of the safety output signal is switched.

5. 5. The safety controller according to claim 1, wherein, when the safety input device is a light curtain, the WEB client identifiably displays the amount of light received for each optical axis of the light curtain based on the status information.

6. 6. The safety controller according to claim 5, wherein the WEB client further displays a threshold value of the amount of received light at which a warning is issued in an identifiable manner.

7. 7. The safety controller according to claim 1, wherein, when the safety input device is a door switch, the WEB client displays a lock state of the door switch based on the state information.

8. 8. The safety controller according to claim 7, wherein the WEB client displays the lock status of all the doors when a plurality of the door switches are cascade-connected.

9. The port is a port to which at least a signal line and a communication line can be connected, 9. The safety controller according to claim 1, wherein the acquiring means acquires a safety input signal via the signal line and acquires the status information via the communication line.

10. 10. The safety controller according to claim 9, wherein the port is a port to which a cable capable of supplying power can be connected in addition to the signal line and the communication line.

Images