JP4494313B2 - Relay output device - Google Patents

Description

  The present invention relates to a relay output device that is required for fail-safety used in a railway signal security system and the like, and particularly relates to miniaturization and cost reduction without affecting the global environment.

  In a railway signal security system, a fail-safe property is required for a device to be used in order to ensure transportation safety. As described in Patent Document 1, as a drive circuit for an output relay used in a system that requires fail-safety as described above, a photocoupler and one terminal are connected to one pole of a DC power supply and the other terminal Is connected to one terminal of the output relay, the first switching circuit having a transistor that is conductive when the photocoupler emits light, the photocoupler, and one terminal connected to the other pole of the DC power supply, The terminal is connected to the other terminal of the output relay, and is connected to the second switching circuit having a transistor that conducts when the photocoupler emits light, and to the output terminals of the first switching circuit and the second switching circuit. A sensor for monitoring a potential state between them and outputting a check signal is provided.

Then, a DC control signal is simultaneously input to the photocouplers of the first switch circuit and the second switch circuit, the photocouplers of both switch circuits are issued, the transistor is turned on, the coil of the output relay is excited, and the DC control is performed. When neither or one of the signals is input, the coil of the output relay is de-energized. When controlling the operation of the output relay, the sensor monitors the potential state between the output terminals of the first switch circuit and the second switch circuit, outputs a check signal, and outputs the check signal to the first switch circuit and the second switch circuit. The combination of the application state of the DC control signal input to each of the switching circuits and the state of the check signal are externally monitored to detect the occurrence of a failure in the output relay drive circuit.
Japanese Patent Publication No. 6-4415

  The drive circuit of the output relay disclosed in Patent Document 1 detects whether or not a failure has occurred in the first switching circuit and the second switching circuit, but does not monitor the operating state of the output relay itself. There is a disadvantage that the failure of the relay cannot be diagnosed.

  In addition, the output relays used in railway signal security systems are large-sized using contact materials that are difficult to weld as countermeasures against sudden wear, relocation, vapor deposition, etc. of contacts due to discharge phenomenon due to chattering of contacts generated during operation. A signal relay is used. For this reason, the output relay becomes expensive. In addition, since the output relay is large, various devices using the output relay are large. Furthermore, contact materials that are difficult to weld for use in output relays contain harmful substances such as cadmium, and therefore it is necessary to urgently consider replacing contact materials as a countermeasure for global environmental regulations.

  An object of the present invention is to provide a fail-safe relay output device using a small general-purpose relay using a contact material that does not affect the global environment while improving such disadvantages.

The relay output device of the present invention includes a fail-safe computer (hereinafter referred to as a computer), a relay drive circuit, an output relay, a contact check input circuit, a semiconductor switch, a sensor, and a switch / sensor input / output circuit. The output relay is controlled to be turned on and off by the relay control signal output from the computer, and the contact check input circuit checks that the operation contact of the output relay output from the computer at a constant cycle is closed. RY input that indicates the operating status of the output relay that is sent from the common contact of the output relay by sending an R contact verification signal that checks that the recovery contact of the signal and the output relay is closed to the operating contact and recovery contact of the output relay The signal is output to the computer, the semiconductor switch is connected in series with the operating contact of the output relay, The sensor is connected to the power input terminal on the opposite side of the semiconductor switch output side and the power switch input terminal to which the semiconductor switch for field equipment drive power is connected, and the semiconductor switch is turned on / off. The switch sensor I / O circuit detects the status and controls the semiconductor switch on / off by the switch control signal input from the computer, and outputs the sensor status signal indicating the on / off status of the semiconductor switch detected by the sensor to the computer. And
When the computer controls the output of the output circuit to ON, the relay control signal is turned ON to control the output relay to the operating side, and the N contact verification signal and the R contact verification signal are output to the contact verification input circuit. Chattering operation of the output contact of the output relay based on the RY input signal input from the common contact of the output relay via the contact check input circuit by checking the operating status of the output relay operating contact and recovery contact connected to the input circuit After confirming that the switch switch signal is turned on, the switch / sensor input / output circuit controls the semiconductor switch to the conduction side, monitors the sensor status signal input from the switch / sensor input / output circuit, and the semiconductor switch When confirming that the continuity state has been detected and controlling the output of the output circuit to turn off, turn off the switch control signal. Characterized in that the semiconductor switches were allowed to control non-conductive side turns off the relay control signal for controlling the output relay recovery side.

  When the computer outputs the N contact check signal and the R contact check signal to check the operation state of the operation contact and the recovery contact of the output relay, the N contact check signal and the R contact check signal are common to the output relay. The failure of the output relay is diagnosed by a combination with the RY input signal input from the contact through the contact verification input circuit.

  In addition, after confirming that the semiconductor switch is turned on, the computer turns off the switch control signal for a moment to check whether the output side of the semiconductor switch is fixed to the on side, and the semiconductor switch is turned off. When the recovery contact of the output relay is closed in this state, the switch control signal is turned on for a moment to check whether the output side of the semiconductor switch is fixed to the off side, thereby diagnosing the failure of the semiconductor switch.

  Further, the computer has a plurality of output relays and output circuits, and the computer is a safe side in which the contact state of any output relay is indefinite or the recovery contact is closed when each output relay is on-controlled. When only the corresponding output circuit is stopped and each output relay is turned off, when the contact state of one of the output relays is indefinite, the functions of all the output circuits are stopped. .

  In this invention, after controlling the output relay to the operating side and confirming that the chattering operation of the operating contact of the output relay has been completed, the semiconductor switch is turned on and the semiconductor switch is turned off, and then the output relay Since the output relay contact is controlled to the recovery side, it prevents the contact of the output relay from being consumed suddenly due to the discharge phenomenon, transfer or welding, etc., and it is unnecessary to use the contact material that affects the global environment as the output relay contact. The relay can be miniaturized. In addition, since the contact of the output relay is not consumed, transferred, or welded, the output relay can be used stably for a long period of time.

  In addition, since the operation status of the output relay operating contact and recovery contact and the operating status of the semiconductor switch are checked by a computer, it is possible to detect the failure of the output relay and the semiconductor switch reliably, making the relay output safe and fault-tolerant. Can be increased.

  In addition, when there are multiple output relays and output circuits, the computer controls each output relay to be on, the contact state of any output relay is indeterminate, or the recovery contact is closed Because only the corresponding output circuit stops functioning and each output relay is turned off, and when the contact state of any output relay is on the dangerous side, all output circuit functions are stopped. , Can improve safety.

  FIG. 1 is a block diagram showing the configuration of the relay output device of the present invention. As shown in the figure, a relay output device 1 includes a fail-safe computer (hereinafter referred to as a computer) 2, a relay drive circuit 3, an output relay 4, a contact verification input circuit 5, a semiconductor switch 6, a sensor 7, and a switch / sensor input / output. A circuit 8 is included.

  For example, the computer 2 receives control information from a higher-level electronic interlocking device, manages the operation of the entire device, and outputs information related to relay output to the electronic interlocking device as display information. The relay drive circuit 3 has, for example, a transistor array 31 and controls the output relay 4 on (operation) and off (recovery) by a relay control signal output from the computer 2. The contact verification input circuit 5 is common to the output relay 4, the transistor array 51 connected to the operation contact (N contact) of the output relay 4, the transistor array 52 connected to the recovery contact (R contact) of the output relay 4, and the output relay 4. An N contact check signal for checking that the operation contact of the output relay 4 output from the computer 2 is closed and a recovery contact of the output relay 4 are provided. The transistor array 53 is connected to the contact (C contact). An R contact check signal for checking that the relay is closed is sent to the operation contact and the recovery contact of the output relay 4, and an RY input signal indicating the operation state of the output relay 4 input from the common contact of the output relay 4 is sent to the computer 2. Output. The semiconductor switch 6 is composed of, for example, a photomoss relay having no chattering and a low on-resistance and direct current output, and is connected in series with the operation contact of the output relay 3 to constitute an output circuit 10 to an external field device 9. . The operation contacts of the output relay 3 constituting the output circuit 10 are provided on both lines of the output circuit 10, respectively, to avoid an erroneous output when one line is mixed with a cable of another output circuit. The sensor 7 is composed of, for example, a DC input photocoupler, and is connected to a power input terminal on the opposite side of the output side of the semiconductor switch 6 and the power switch input terminal to which the semiconductor switch 6 of the field device drive power supply 11 is connected. 6 ON / OFF state is detected. The switch / sensor input / output circuit 8 includes a transistor array 81 connected to the drive side of the semiconductor switch 6 and a transistor array 82 connected to the output side of the sensor 7. 6 is turned on / off, and a sensor state signal indicating the on / off state of the semiconductor switch 6 detected by the sensor 7 is output to the computer 2.

  The operation of the relay output device 1 will be described with reference to the time chart of FIG.

  When the relay output of the relay output device 1 is controlled from OFF to ON, as shown in FIG. 2A, the computer 2 turns on the relay control signal and outputs it to the relay drive circuit 3 to operate the output relay 4. Control, the N contact verification signal and the R contact verification signal are output to the contact verification input circuit 5, and the operation status of the operating contact and the recovery contact of the output relay 4 connected to the contact verification input circuit 5 are verified. The state of the operating contact of the output relay 4 is grasped by the RY input signal input from the common contact of the output relay 4 via the contact verification input circuit 5. FIG. 3A shows a check timing and a truth table when grasping the operation state of the operation contact and the recovery contact of the output relay 4. As shown in FIG. 3A, the computer 2 intermittently outputs the N contact check signal and the R contact check signal to the contact check input circuit 5 at regular intervals, and operates the operation contact and the recovery contact of the output relay 4. Check the state and input the RY input signal. When it is confirmed that the process No. 1 to No. 6 are repeated for a certain number of times, it is determined that the contact chattering operation has ended and the operation contact has been securely closed, the switch control signal is turned on, and the switch / sensor input / output circuit 8 is turned on. Thus, the semiconductor switch 6 is controlled to the conduction side. Then, the sensor state signal input from the switch / sensor input / output circuit 8 is monitored, and it is confirmed that the sensor 7 detects that the semiconductor switch 6 is turned on. When the output relay 4 is in the operating state, the operation contact of the output relay 4 provided in the output circuit is turned on, and the semiconductor switch 6 is turned on, the relay output is supplied from the field device drive power supply 11 via the output circuit 10 to the field device. Send to 9.

  When the relay output is controlled to be turned off in this state, as shown in FIG. 2 (b), the computer 2 turns off the switch control signal and causes the switch / sensor input / output circuit 8 to move the semiconductor switch 6 to the non-conductive side. Let me control. When the sensor state signal input from the switch / sensor input / output circuit 8 is monitored and it is confirmed that the sensor 7 detects that the semiconductor switch 6 is in a non-conductive state, the field device drive power supply 11 sends the field device 9 to the field device 9. Judge that the sending relay output is turned off. Thereafter, the relay control signal is turned off and output to the relay drive circuit 3 to control the output relay 4 to the recovery side, and the N contact verification signal and the R contact verification signal are output to the contact verification input circuit 5. The operating state of the operating contact and the recovery contact of the output relay 4 connected to the output relay 4 is checked, and the recovery contact of the output relay 4 is determined by the RY input signal input from the common contact of the output relay 4 via the contact verification input circuit 5. Know the status. When grasping the state of the recovery contact of the output relay 4, the computer 2 intermittently sends the N contact check signal and the R contact check signal to the contact check input circuit 5 at regular intervals as shown in FIG. An output is performed to check the operation state of the operation contact and the recovery contact of the output relay 4, and the RY input signal is input. When it is confirmed that the process No. 1 to No. 6 are repeated for a certain number of times, the chattering operation of the contact ends and it is determined that the restoration contact is reliably closed.

  After controlling the output relay 4 to the operating side in this way and confirming that the chattering operation of the operating contact of the output relay 4 has been completed, the semiconductor switch 6 is turned on and the semiconductor switch is turned off. Since the output relay 4 is controlled to the recovery side, the contact of the output relay 4 can be prevented from being rapidly consumed due to a discharge phenomenon, or transfer or welding can be prevented. The contact of the output relay 4 includes, for example, cadmium. It is not necessary to use contact materials that affect the global environment, and the output relay can be miniaturized. In addition, since the contact of the output relay 4 is not consumed, transferred, or welded, the output relay 4 can be used stably for a long period of time.

  Further, the computer 2 outputs the N contact verification signal and the R contact verification signal to the contact verification input circuit 5, and checks the operation status of the operating contact and the recovery contact of the output relay 4 connected to the contact verification input circuit 5. When the output relay 4 is in operation, the operating state of the operation contact and the recovery contact of the output relay 4 can be confirmed by the RY input signal input from the common contact of the output relay 4 via the contact verification input circuit 5. be able to. That is, when the computer 2 is turning on the N contact verification signal and outputting it to the contact verification input circuit 5 to check the operation state of the operating contact of the output relay 4, the RY input signal does not turn on, If the RY input signal does not turn off when the signal is turned off, it is determined that a failure has occurred in the output relay 4. Also, when the R contact verification signal is turned on and the operation state of the recovery contact of the output relay 4 is being verified, the RY input signal is not turned on, or when the R contact verification signal is turned off, the RY input signal is turned off. If not, it is determined that the output relay 4 has failed.

  Next, processing when the relay output device 1 diagnoses whether or not the semiconductor switch 6 has failed will be described with reference to the check timing and truth table of FIG.

  The computer 2 turns on the relay control signal to control the output relay 4 to the operating side, and after the chattering operation of the operating contact and the recovery contact of the output relay 4 is completed and the operating contact is securely closed, the switch control signal is output. After turning on and controlling the semiconductor switch 6 to the conduction side and confirming that the semiconductor switch 6 is turned on by the sensor state signal, the switch control signal is turned off for a moment as shown in FIG. Then, it is confirmed whether or not the output side of the semiconductor switch 6 is fixed to the ON side. When this process is repeated at regular intervals and the switch control signal is turned off, the semiconductor switch 6 is determined to be operating normally when the semiconductor switch 6 is turned off by the sensor state signal, and the switch control signal is If the semiconductor switch 6 remains in a conducting state by the sensor state signal when it is turned off, the semiconductor switch 6 determines that it has failed and stops the function of the output circuit 10.

  Further, the computer 2 turns off the switch control signal, controls the semiconductor switch 6 to the non-conductive side by the switch / sensor input / output circuit 8, and detects that the semiconductor switch 6 has become non-conductive based on the sensor status signal. After that, the relay control signal is turned off and the output relay 4 is controlled to the recovery side, and after confirming that the chattering operation of the contact of the output relay 4 is completed and the recovery contact is securely closed, FIG. As shown, the switch control signal is turned on for a moment to check whether the output side of the semiconductor switch 6 is fixed to the off side. When this process is repeated at regular intervals and the switch control signal is turned on, if the semiconductor switch 6 is turned on by the sensor state signal, it is determined that the semiconductor switch 6 is operating normally, and the switch control signal is turned on. In this case, if the semiconductor switch 6 remains in a non-conductive state due to the sensor state signal, the semiconductor switch 6 is determined to be faulty and the function of the output circuit 10 is stopped.

  As described above, the computer 2 can reliably detect the failure of the output relay 4 and the semiconductor switch 6 based on the operating state of the operating contact and the recovery contact of the output relay 4 and the operating state of the semiconductor switch 6, and safety of the relay output. As a result, fault tolerance can be improved.

  In the above description, a case where a set of output circuits 10 is provided in the relay output device 1 has been described. However, when a plurality of sets of output circuits 10 are provided in the relay output device 1, the contact verification input circuit 5 is shown in FIG. As described above, the N contact verification signal and the R contact verification signal may be input to the operation contact and the recovery contact of each output relay 4 in common. In this case, when the computer 2 controls each output relay to be on, if the contact state of any output relay is indefinite or the recovery contact is closed, the operating contact of the output relay is Only the connected output circuit 10 stops functioning. In addition, when the output relay of each output relay is controlled, the computer 2 stops the functions of all the output circuits 10 when the contact state of any output relay is indefinite, thereby improving safety. Can be made.

  In the above description, the case where the transistor array is used for the relay drive circuit 3, the contact checking input circuit 5, and the switch / sensor input / output circuit 8 has been described. However, a photocoupler may be used. Further, an AC / DC photoMOS relay may be used for the semiconductor switch 6, and an AC / DC input photocoupler may be used for the sensor 7.

It is a block diagram which shows the structure of the relay output device of this invention. It is a time chart which shows operation | movement of a relay output apparatus. It is a figure which shows the check timing and truth table when confirming the contact state of an output relay. It is a figure which shows the check timing and truth table of failure diagnosis operation | movement of a semiconductor switch. It is a block diagram of the contact verification input circuit in the case of multiple outputs.

Explanation of symbols

1; relay output device, 2; fail-safe computer, 3; relay drive circuit,
4; output relay, 5; contact verification input circuit, 6; semiconductor switch, 7; sensor,
8; switch sensor input / output circuit, 9; field device, 10; output circuit,
11: On-site equipment drive power supply.

Claims (4)

A fail-safe computer (hereinafter referred to as a computer), a relay drive circuit, an output relay, a contact check input circuit, a semiconductor switch, a sensor, and a switch / sensor input / output circuit;
The relay drive circuit controls on / off of the output relay by a relay control signal output from the computer,
The contact check input circuit checks that the N contact check signal for checking that the operation contact of the output relay output from the computer at a constant cycle is closed and the recovery contact of the output relay are closed. Send R contact verification signal to the operation contact and recovery contact of the output relay, and output RY input signal indicating the operation status of the output relay input from the common contact of the output relay to the computer,
The semiconductor switch is connected in series with the operating contact of the output relay and constitutes an output circuit to external field equipment,
The sensor is connected to the power input terminal on the side opposite to the output side of the semiconductor switch and the power input terminal to which the semiconductor switch of the field device driving power source is connected, and detects the on / off state of the semiconductor switch,
The switch sensor input / output circuit controls the semiconductor switch on / off by a switch control signal input from the computer and outputs a sensor state signal indicating the on / off state of the semiconductor switch detected by the sensor to the computer.
When the computer controls the output of the output circuit to be turned on, the relay control signal is turned on to control the output relay to the operation side, and the N contact check signal and the R contact check signal are output to the contact check input circuit, Checks the operating status of the output relay operating contact and recovery contact connected to the contact verification input circuit, and determines the output relay operating contact by the RY input signal input from the output relay common contact via the contact verification input circuit. After confirming that the chattering operation has ended, the switch control signal is turned on, the semiconductor switch is controlled to the conduction side by the switch / sensor input / output circuit, the sensor status signal input from the switch / sensor input / output circuit is monitored, and the semiconductor Confirm that the switch has been turned on,
When controlling the output of the output circuit to OFF, the switch control signal is turned OFF to control the semiconductor switch to the non-conductive side, and then the relay control signal is turned OFF to control the output relay to the recovery side. Relay output device.   When the computer outputs the N contact check signal and the R contact check signal to check the operation state of the operation contact and the recovery contact of the output relay, the N contact check signal and the R contact check signal are common to the output relay. 2. The relay output device according to claim 1, wherein a failure of the output relay is diagnosed by a combination with an RY input signal input from the contact via a contact verification input circuit.   After confirming that the semiconductor switch is turned on, the computer turns off the switch control signal for a moment to check whether the output side of the semiconductor switch is fixed to the on side, and the semiconductor switch is turned off. And diagnosing a failure of the semiconductor switch by checking whether the output side of the semiconductor switch is fixed to the OFF side by turning on the switch control signal for a moment when the recovery contact of the output relay is closed. The relay output device according to 1 or 2. A plurality of output relays and output circuits;
When the computer is on-controlling each output relay, when the contact state of any output relay is indeterminate or the recovery contact is closed, only the corresponding output circuit stops functioning, The relay according to any one of claims 1 to 3, wherein when the output relays are controlled to be off, the functions of all the output circuits are stopped when the contact state of any of the output relays is on the dangerous side. Output device.

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