JP6169305B1 - Power shut-off device - Google Patents

Abstract

The power cut-off device cuts off power supplied from the power supply to the circuit. The power shut-off device includes a switch circuit, a first detector, a second detector, and a control device. The switch circuit branches from between the power supply and the fuse connected to the circuit and the circuit, and the first switch and the second switch are connected in series. The first detector detects the operating state of the first switch. The second detector detects the operating state of the second switch. The control device executes a first operation mode and a second operation mode. In the first operation mode, the control device obtains the detection value of the first detector or the detection value of the second detector while alternately turning on or off the first switch and the second switch to obtain the state of the switch circuit. Determine. In the second operation mode, the control device turns on both the first switch and the second switch.

Description

  The present invention relates to a power cutoff device that cuts off power supplied from a power source to a circuit.

  There is a circuit that operates by receiving power from a power source. There is known a power cutoff device that cuts off power supplied from a power source to a circuit when such a circuit has a problem.

JP 2012-101302 A

  There is a demand to detect the state of the power shut-off device in order to check whether the power shut-off device operates normally during the operation of the circuit. Patent Document 1 describes a technique for reliably realizing a fail safe for a power tool circuit and a power tool. However, since the technology of Patent Document 1 cannot confirm that the brake switching element and the drive switching element function normally in a state where the motor is driven, a problem occurs in the drive switching element during driving of the motor. Cannot be detected.

  An object of the present invention is to detect the state of a means for shutting off a power supply in a state where the circuit is operating by supplying power from the power supply to the circuit.

The power cutoff device according to the present invention cuts off the power supplied from the power source to the circuit. The power shut-off device includes a switch circuit, a first detector, a second detector, and a control device. The switch circuit branches from between the power supply and the fuse connected to the circuit and the circuit, and the first switch and the second switch are connected in series. The first detector detects the H level when the first switch is turned on, and detects the L level when the first switch is turned off . The second detector detects the H level when the second switch is turned on, and detects the L level when the second switch is turned off . The control device executes a first operation mode and a second operation mode. In the first operation mode, the control device obtains the detection value of the first detector or the detection value of the second detector while alternately turning on or off the first switch and the second switch to obtain the state of the switch circuit. Determine. In the second operation mode, the control device turns on both the first switch and the second switch. In the control device, the detection value of the first detector is H level and the detection value of the second detector is L level, or the detection value of the first detector is L level and the detection value of the second detector is H level. If so, it is determined that the first switch and the second switch are operating normally .

  The present invention has an effect that the state of the means for shutting off the power supply can be detected in a state where the circuit is operating by supplying power from the power supply to the circuit.

The figure which shows the power-supply-cutoff apparatus which concerns on Embodiment 1. The figure which shows the relationship between the state of the 1st switch which concerns on Embodiment 1, and a 2nd switch, and a detected value In Embodiment 1, the timing chart of the operation signal given to the first switch and the operation signal given to the second switch The figure which shows the functional block of the control apparatus which the power-supply-cutoff apparatus which concerns on Embodiment 1 has. The figure which shows the hardware constitutions of the control apparatus which concerns on Embodiment 1. The figure which shows the hardware constitutions of the control apparatus which concerns on Embodiment 1. Flowchart of a power shutoff method executed by the power shutoff device according to Embodiment 1 The figure which shows the 1st detector and 2nd detector which concern on the modification of Embodiment 1. FIG. The figure which shows the power-supply-cutoff apparatus which concerns on Embodiment 2. The figure which shows the relationship between the state of the 1st switch which concerns on Embodiment 2, and a 2nd switch, and a detected value In Embodiment 2, the timing chart of the operation signal given to the first switch and the operation signal given to the second switch

  Hereinafter, a power shutoff device according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a power shut-off device 1 according to the first embodiment. The power shut-off device 1 is incorporated in a device control device 10 that controls the device 20. The device control apparatus 10 includes a drive circuit 11 and a circuit 12. The drive circuit 11 is a circuit for driving an actuator 21 such as an electric motor, an air cylinder, and a solenoid included in the device 20. The circuit 12 generates a control signal for operating the actuator 21 and supplies it to the drive circuit 11. The drive circuit 11 generates a drive signal for driving the actuator 21 based on the control signal received from the circuit 12 and supplies the drive signal to the actuator 21. When the actuator 21 is driven, the device 20 operates. Although the apparatus 20 is a robot, a machine tool, a conveying apparatus, and an air conditioner, it is not limited to these.

  The circuit 12 is supplied with power from the power supply 13. The power cut-off device 1 is a device that cuts off power supplied from the power supply 13 to the circuit 12. The power cut-off device 1 operates when an abnormality occurs in the circuit 12 and cuts off the power supplied to the circuit 12. A fuse 14 is provided between the power supply 13 and the circuit 12. That is, the fuse 14 is electrically connected to the power supply 13 and the circuit 12. The power cutoff device 1 cuts off the power supplied from the power source 13 to the circuit 12 by blowing the fuse 14. In the following, the connection means an electrical connection unless otherwise specified.

  The power shutoff device 1 includes a switch circuit 2, a first detector 3 </ b> F, a second detector 3 </ b> S, and a control device 4. The switch circuit 2 includes a first switch 2F and a second switch 2S. The switch circuit 2 has one end connected between the fuse 14 and the circuit 12 and the other end connected to the ground. Specifically, the first end Tf of the first switch 2 </ b> F is connected between the fuse 14 and the circuit 12. The second end Ts of the first switch 2F and the first end Tf of the second switch 2S are connected. The second terminal Ts of the second switch 2S is connected to the ground. Thus, the first switch 2F and the second switch 2S branch from between the fuse 14 and the circuit 12 and are connected in series. The first switch 2F and the second switch 2S are exemplified by switching elements, but are not limited thereto.

  The first detector 3F detects the operating state of the first switch 2F. The second detector 3S detects the operation status of the second switch 2S. Both the first detector 3F and the second detector 3S have the same structure. In the first embodiment, the first detector 3F and the second detector 3S are photocouplers in which the light-emitting diode 5 and the phototransistor 6 are combined, but the operation status of the first switch 2F and the second switch 2S is detected. If possible, it is not limited to a photocoupler.

  The first detector 3F and the second detector 3S have input terminals 5I and 6I and output terminals 5E and 6E. The input terminal 5I is a terminal on the anode side of the light emitting diode 5, and the input terminal 6I is a terminal on the collector side of the phototransistor 6. The output terminal 5E is a terminal on the cathode side of the light emitting diode 5, and the output terminal 6E is a terminal on the emitter side of the phototransistor 6.

  The input terminal 5 </ b> I of the first detector 3 </ b> F is connected between the fuse 14 and the circuit 12, specifically, between the part branched to the switch circuit 2 and the circuit 12. The output terminal 5E of the first detector 3F and the input terminal 5I of the second detector 3S are connected via a resistor R1. The resistor R1 and the input terminal 5I of the second detector 3S are connected between the second end Ts of the first switch 2F and the first end Tf of the second switch 2S. The output terminal 5E of the second detector 3S is connected between the second end Ts of the second switch 2S and the ground via a resistor R2.

  The input terminal 6I of the first detector 3F is connected to the power source 7 via the resistor R3. The output terminal 6E of the first detector 3F is connected to the ground. The input terminal 6I of the second detector 3S is connected to the power source 7 via the resistor R4. The output terminal 6E of the second detector 3S is connected to the ground. The power source 7 is a power source for driving the power shut-off device 1. The power source 7 may be a power source different from the power source 13, or may be a voltage obtained by stepping down the voltage of the power source 13.

  A signal line SL1 is connected between the input terminal 6I of the first detector 3F and the power source 7, and more specifically, between the input terminal 6I and the resistor R3. The signal line SL1 is connected to the control device 4. The signal line SL2 is connected between the input terminal 6I of the second detector 3S and the power source 7, and more specifically, between the input terminal 6I and the resistor R4. The signal line SL2 is connected to the control device 4. With such a structure, the control device 4 acquires the potential of the input terminal 6I of the first detector 3F and the potential of the input terminal 6I of the second detector 3S.

  In a state where the light emitting diode 5 is not emitting light, the first detector 3F and the second detector 3S are off. In this case, the potential of the input terminal 6I of the first detector 3F and the potential of the input terminal 6I of the second detector 3S are values obtained by dropping the voltage of the power supply 7 by the resistors R3 and R4. Hereinafter, the potential of the input terminal 6I when the first detector 3F and the second detector 3S are off is appropriately referred to as H level.

  When the light emitting diode 5 emits light, the first detector 3F and the second detector 3S are turned on. In this case, the potential of the input terminal 6I of the first detector 3F and the potential of the input terminal 6I of the second detector 3S are ground potentials. Hereinafter, the potential of the input terminal 6I when the first detector 3F and the second detector 3S are on is appropriately referred to as L level.

  When the first switch 2F is turned on, a current flows from the power source 13 in the order of the fuse 14, the first switch 2F, the second detector 3S, the resistor R2, and the ground. Then, the light emitting diode 5 of the second detector 3S emits light and the phototransistor 6 is turned on, so that the potential of the input terminal 6I of the second detector 3S becomes L level. In this case, since the light emitting diode 5 of the first detector 3F does not emit light, the phototransistor 6 is turned off, and as a result, the potential of the input terminal 6I of the first detector 3F becomes H level. When the first switch 2F is turned off, the potential of the input terminal 6I of the first detector 3F becomes L level.

  When the second switch 2S is turned on, a current flows from the power source 13 in the order of the fuse 14, the first detector 3F, the resistor R1, the second switch 2S, and the ground. Then, the light emitting diode 5 of the first detector 3F emits light and the phototransistor 6 is turned on, so that the potential of the input terminal 6I of the first detector 3F becomes L level. In this case, since the light emitting diode 5 of the second detector 3S does not emit light, the phototransistor 6 is turned off, and as a result, the potential of the input terminal 6I of the second detector 3S becomes H level. When the second switch 2S is turned off, the potential of the input terminal 6I of the second detector 3S becomes L level.

  When the first switch 2F is turned on, the potential of the input terminal 6I of the first detector 3F becomes H level, and when the first switch 2F is turned off, the potential of the input terminal 6I of the first detector 3F becomes L level. When the second switch 2S is turned on, the potential of the input terminal 6I of the second detector 3S becomes H level, and when the second switch 2S is turned off, the potential of the input terminal 6I of the second detector 3S becomes L level. Thus, the first detector 3F detects the on / off state of the first switch 2F, and the second detector 3S detects the on / off state of the second switch 2S.

  When the potential of the input terminal 6I of the first detector 3F is SI1, and the potential of the input terminal 6I of the second detector 3S is SI2, the potential SI1 is the result of the first detector 3F detecting the state of the first switch 2F. Yes, the potential SI2 is the result of the second detector 3S detecting the state of the second switch 2S. Hereinafter, the potential SI1 is appropriately referred to as a detection value SI1, and the potential SI2 is appropriately referred to as a detection value SI2. In the first embodiment, the detection values SI1 and SI2 are both at the H level or the L level.

  FIG. 2 is a diagram illustrating a relationship between the states of the first switch 2F and the second switch 2S according to the first embodiment and the detection values SI1 and SI2. As shown in FIG. 2, whether the first switch 2F and the second switch 2S are on or off is determined depending on whether the detection values SI1 and SI2 are at the H level or the L level. Based on the detection value SI1 of the first detector 3F and the detection value SI2 of the second detector 3S, the control device 4 determines whether the state of the switch circuit 2, specifically, the first switch 2F and the second switch 2S are on or off. It is determined whether it is.

  The control device 4 operates the first switch 2F and the second switch 2S. Specifically, the control device 4 turns on the first switch 2F and the second switch 2S by giving the operation signal SE1 to the first switch 2F and giving the operation signal SE2 to the second switch 2S. The first switch 2F and the second switch 2S are turned off when the operation signal SE1 and the operation signal SE2 are not supplied from the control device 4. The control device 4 can operate the first switch 2F and the second switch 2S independently.

  The control device 4 executes the first operation mode and the second operation mode. The first operation mode is a switch circuit that acquires the detection value SI1 of the first detector 3F or the detection value SI2 of the second detector 3S while alternately turning on or off the first switch 2F and the second switch 2S. 2 is determined. In the second operation mode, both the first switch 2F and the second switch 2S are turned on.

  The first operation mode is used for confirming the operation of the switch circuit 2. The second operation mode is used to cut off power supplied from the power supply 13 to the circuit 12 by cutting off the power supply 13 and the circuit 12. In the first operation mode, the control device 4 turns off the second switch 2S at the timing of turning on the first switch 2F. Further, the control device 4 turns on the second switch 2S at the timing of turning off the first switch 2F.

  When the first switch 2F is on and the second switch 2S is off, as shown in FIG. 2, if the detection value SI1 is H level and the detection value SI2 is L level, the first switch 2F and the second switch The switch 2S is operating normally. When the first switch 2F is OFF and the second switch 2S is ON, as shown in FIG. 2, if the detection value SI1 is L level and the detection value SI2 is H level, the first switch 2F and the second switch The switch 2S is operating normally.

  In the first operation mode, the control device 4 applies the operation signal SE1 to the first switch 2F, does not apply the operation signal SE1 to the second switch 2S, and sends the detection value SI1 from the first detector 3F to the second The detection value SI2 is acquired from the detector 3S. As shown in FIG. 2, if the detection value SI1 of the first detector 3F is H level and the detection value SI2 of the second detector 3S is L level, the first switch 2F and the second switch 2S operate normally. doing.

  Next, the control device 4 gives the operation signal SE2 to the second switch 2S, does not give the operation signal SE2 to the first switch 2F, and sends the detection value SI1 from the first detector 3F to the second detector 3S. The detection value SI2 is acquired. As shown in FIG. 2, if the detection value SI1 of the first detector 3F is L level and the detection value SI2 of the second detector 3S is H level, the first switch 2F and the second switch 2S operate normally. doing.

  The control device 4 acquires the detection value SI1 of the first detector 3F and the detection value SI2 of the second detector 3S while alternately turning on or off the first switch 2F and the second switch 2S. That is, the control device 4 turns off the second switch 2S when the first switch 2F is on, and turns on the second switch 2S when the first switch 2F is off. Thus, the control device 4 exclusively turns on or off the first switch 2F and the second switch 2S in the first operation mode. The control device 4 determines the state of the switch circuit 2, in detail, whether the first switch 2F and the second switch 2S are normal or abnormal, from the detection values SI1 and SI2.

  If the second switch 2S is off even if the first switch 2F is on, the current from the power source 13 flows to the circuit 12 through the fuse 14. Similarly, even if the second switch 2S is on, if the first switch 2F is off, the current from the power supply 13 flows through the fuse 14 to the circuit 12. For this reason, the control device 4 can determine the state of the switch circuit 2 without interrupting the supply of power from the power supply 13 to the circuit 12, and therefore can determine the state of the switch circuit 2 while operating the circuit 12. Thus, the control device 4 can detect a state in which the fuse 14 cannot be blown without flowing a large current through the fuse 14 in a state where power is supplied from the power supply 13 to the circuit 12. That is, the power shut-off device 1 can reduce the possibility that a failure occurs in the entire device control device 10 due to the failure of the switch circuit 2.

  In the first embodiment, the control device 4 outputs the determination result RJ of the state of the switch circuit 2 during execution of the first operation mode. The determination result RJ is the state of the switch circuit 2, more specifically, whether the first switch 2F and the second switch 2S are normal or whether at least one of the first switch 2F and the second switch 2S is abnormal. . In the former case, the switch circuit 2 is normal, and in the latter case, the switch circuit 2 is abnormal. The control device 4 may output 0 or Low as the determination result RJ when the switch circuit 2 is normal, and may output 1 or High as the determination result RJ when the switch circuit 2 is abnormal.

  The determination result RJ is not limited to that described above. The determination result RJ may be information for notifying whether the switch circuit 2 is normal or abnormal. In this case, the control device 4 can output the determination result RJ to the display device 22 to display whether the switch circuit 2 is normal or abnormal. When the display device 22 displays that the switch circuit 2 is abnormal, the operator of the device 20 can stop the device 20 or continue the operation of the device 20 while limiting the function.

  The determination result RJ may be an instruction for stopping the operation of the circuit 12 or an instruction for continuing the operation of the circuit 12. In this case, when it is determined that the switch circuit 2 is abnormal, the control device 4 can output a command for stopping the operation of the circuit 12 to the circuit 12 as the determination result RJ, and can stop the circuit 12. If an abnormality has occurred in the switch circuit 2, there is a possibility that the supply of power from the power supply 13 to the circuit 12 cannot be interrupted when an abnormality has occurred in the switch circuit 2. When abnormality occurs in the circuit 12, the controller 4 outputs a command to stop the circuit 12 as the determination result RJ to the circuit 12, so that the power supply from the power supply 13 to the circuit 12 may not be cut off. Thus, the operation of the circuit 12 can be prevented from continuing.

  In the second operation mode, the control device 4 turns on both the first switch 2F and the second switch 2S. Then, since a current flows from the power source 13 to the ground through the fuse 14, the first switch 2F, and the second switch 2S, the fuse 14 is blown. When the fuse 14 is blown, the power supply from the power supply 13 to the circuit 12 is cut off, so that the circuit 12 stops operating. When receiving the abnormality occurrence information IE, which is information indicating that an abnormality has occurred in the circuit 12, from the circuit 12, the control device 4 starts the second operation mode.

  When the control device 4 receives the abnormality occurrence information IE from the circuit 12, the control device 4 executes the second operation mode to cut off the supply of power from the power supply 13 to the circuit 12. As a result, it is possible to avoid a state in which power is continuously supplied from the power supply 13 to the circuit 12 that has become abnormal.

  FIG. 3 is a timing chart of the operation signal SE1 applied to the first switch 2F and the operation signal SE2 applied to the second switch 2S in the first embodiment. The horizontal axis in FIG. 3 is time t. The first switch 2F is turned on when the operation signal SE1 is H, and the first switch 2F is turned off when the operation signal SE1 is L. The second switch 2S is turned on when the operation signal SE2 is H, and the second switch 2S is turned off when the operation signal SE2 is L.

  As described above, when both the first switch 2F and the second switch 2S are turned on, a current flows from the power supply 13 through the fuse 14 to the ground, and the fuse 14 is blown. For this reason, when the control device 4 operates the first switch 2F and the second switch 2S in the first operation mode, the fuse 14 may be blown if both are turned on simultaneously.

  In the first operation mode, the control device 4 provides a period in which both the first switch 2F and the second switch 2S are turned off, and alternately turns on or off the first switch 2F and the second switch 2S. Specifically, as shown in FIG. 3, the control device 4 provides a period during which both the operation signal SE1 and the operation signal SE2 are L. At time t1, the operation signal SE1 changes from H to L, but the operation signal SE2 maintains L. The operation signal SE2 changes from L to H at time t2 after time t1. At time t3, the operation signal SE2 changes from H to L, but the operation signal SE1 maintains L. The operation signal SE1 changes from L to H at time t4 after time t3. That is, both the first switch 2F and the second switch 2S are turned off between the time t1 and the time t2 and between the time t3 and the time t4.

  In the first operation mode, the control device 4 provides a period during which both the first switch 2F and the second switch 2S are turned off when the first switch 2F and the second switch 2S are alternately turned on or off. Thus, the fuse 14 is avoided from being blown. As a result, the stop of the operation of the circuit 12 is avoided while the control device 4 is executing the first operation mode.

  FIG. 4 is a functional block diagram of the control device 4 included in the power shutoff device 1 according to the first embodiment. The power shutoff device 1 includes a determination unit 4J and a control unit 4C. The determination unit 4J includes a detection value SI1 of the first detector 3F and a detection value SI2 of the second detector 3S, an operation signal SE1 applied to the first switch 2F, and an operation signal SE2 applied to the second switch 2S. Based on this, the state of the switch circuit 2 is determined. The determination unit 4J outputs a determination result RJ.

  The control unit 4C gives the operation signal SE1 to the first switch 2F to turn on the first switch 2F, and turns off the first switch 2F by not giving the operation signal SE1. Further, the control unit 4C gives the operation signal SE2 to the second switch 2S to turn on the second switch 2S, and turns off the second switch 2S by not giving the operation signal SE2. The control unit 4C operates the first switch 2F and the second switch 2S in the first operation mode when the circuit 12 is operating and when the abnormality occurrence information IE is not received. The controller 4C operates the first switch 2F and the second switch 2S in the second operation mode when the circuit 12 is operating and when the abnormality occurrence information IE is received.

  5 and 6 are diagrams illustrating a hardware configuration of the control device 4 according to the first embodiment. When the function of the control device 4 is realized by software, the control device 4 includes a processor 4P and a memory 4M as shown in FIG. The functions of the determination unit 4J and the control unit 4C included in the control device 4 are realized by the processor 4P. The processor 4P is also referred to as a CPU (Central Processing Unit), a processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor).

  In this case, the functions of the determination unit 4J and the control unit 4C are realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in the memory 4M. The processor 4P implements the functions of the determination unit 4J and the control unit 4C by reading and executing the program stored in the memory 4M. It can be said that these programs cause the computer to execute the procedure executed by the determination unit 4J and the control unit 4C and the power-off method according to the first embodiment.

  The memory 4M realizes the function of the storage unit of the control device 4. The memory 4M includes a volatile or nonvolatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), and an EEPROM (Electrically Erasable Programmable Read Only Memory), Magnetic disks, flexible disks, optical disks, compact disks, mini disks, and DVDs (Digital Versatile Discs) are applicable.

  The functions of the determination unit 4J and the control unit 4C included in the control device 4 may be realized by a processing circuit 4AP illustrated in FIG. The processing circuit 4AP is dedicated hardware for realizing the functions of the determination unit 4J and the control unit 4C. The processing circuit 4AP corresponds to a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. Different functions of the determination unit 4J and the control unit 4C may be realized by different processing circuits 4AP, or the respective functions may be combined and realized by one processing circuit 4AP.

  A part of each function of the determination unit 4J and the control unit 4C may be realized by dedicated hardware, and a part may be realized by software or firmware. Thus, the control device 4 can realize the functions of the determination unit 4J and the control unit 4C by hardware, software, firmware, or a combination thereof.

  FIG. 7 is a flowchart of the power shutoff method executed by the power shutoff device 1 according to the first embodiment. When power is supplied from the power supply 13 to the circuit 12 of the device control apparatus 10, the control apparatus 4 starts operation. In step S101, the control device 4 alternately turns on or off the first switch 2F and the second switch 2S. If an abnormality has occurred in the switch circuit 2 in step S102 (step S102, Yes), the control device 4 outputs a determination result RJ in step S103. If no abnormality occurs in the switch circuit 2 in step S102 (step S102, No), the control device 4 repeats steps S101 and S102.

  FIG. 8 is a diagram showing a first detector 3Fa and a second detector 3Sa according to a modification of the first embodiment. The first detector 3Fa and the second detector 3Sa are switches in which a coil 5a and a switch 6a that is turned on / off by a magnetic force generated by the coil 5a are combined. One end of the coil 5a and the switch 6a serves as input terminals 5Ia and 6Ia, and the other end serves as output terminals 5Ea and 6Ea. In the first detector 3Fa and the second detector 3Sa, the switch 6a is closed when a current flows through the coil 5a, that is, a current flows from the input terminal 6Ia to the output terminal 6Ea. In this way, the detection values SI1 and SI2 at the input terminal 6Ia are the same as the detection values SI1 and SI2 of the first switch 2F and the second switch 2S using the photocoupler described above.

  As described above, the power shut-off device 1 branches from between the fuse 14 connected to the power supply 13 and the circuit 12 and the circuit 12, and the switch circuit 2 in which the first switch 2F and the second switch 2S are connected in series, Control for determining the state of the switch circuit 2 by acquiring the detection value SI1 of the first detector 3F and the detection value SI2 of the second detector 3S while alternately turning on or off the first switch 2F and the second switch 2S. Device 4. For this reason, the power shut-off device 1 is checking the operation of the first switch 2F and the second switch 2S because one of the first switch 2F and the second switch 2S is turned off while the other is turned off. However, the power supply from the power supply 13 to the circuit 12 can be maintained. As a result, the power shut-off device 1 detects the state of the switch circuit 2 in the first embodiment, which supplies power to the circuit 12 from the power source 13 while the circuit 12 is in operation. Can do.

  In the power shutoff device 1, the first switch 2F and the second switch 2S may be different types of elements, or the first detector 3F and the second detector 3S may be different types of elements. . For this reason, since the range of selection of the element used for the power-supply-cutoff apparatus 1 spreads, there also exists an advantage that a structure becomes easy. Further, since the power shutoff device 1 cuts off the supply of power from the power supply 13 to the circuit 12 by fusing the fuse 14, the power supply to the circuit 12 can be cut off reliably.

  In the first embodiment, the power shutoff device 1 is incorporated in the device control device 10, but may not be incorporated in the device control device 10. In the first embodiment, the fuse 14 is not included in the power cutoff device 1, but may be included in the power cutoff device 1. The period for turning on or off the first switch 2F and the second switch 2S is not limited, and is appropriately set according to the specifications of the control device 4 or the circuit 12.

  In the first embodiment, the circuit 12 means a circuit in which electrical elements such as a resistor, an inductor, a capacitor, and a switch are connected by an electrical conductor. For this reason, in the first embodiment, the circuit 12 is a circuit that generates a control signal for controlling the actuator 21 and supplies the control signal to the drive circuit 11. However, the circuit 12 is not limited to such a circuit. This includes relays.

  In the first embodiment, the power shutoff device 1 includes the first switch 2F and the second switch 2S, but the number of switches is not limited to two. That is, the power shut-off device 1 has a plurality of switches, and these may be exclusively turned on or off.

  The configuration of the first embodiment can be applied as appropriate to the following embodiments. Moreover, a part of the configuration of the first embodiment may be deleted, or another configuration may be added.

Embodiment 2. FIG.
FIG. 9 is a diagram illustrating a power shut-off device 1b according to the second embodiment. The power cutoff device 1b is different from the power cutoff device 1 according to the first embodiment in that the first switch 2F and the second switch 2S of the switch circuit 2b are connected in parallel and do not have the fuse 14.

  The switch circuit 2b is disposed between the power supply 13 and the circuit 12 of the device control apparatus 10b. The first switch 2F and the second switch 2S are connected in parallel between the power supply 13 and the circuit 12. A diode 8F is connected between the first switch 2F and the circuit 12. A diode 8S is connected between the second switch 2S and the circuit 12. The diodes 8S and 8F are for preventing the current from the turned-on direction from flowing backward to the other when the first switch 2F or the second switch 2S is turned on.

  The input terminal 5I of the first detector 3F is connected between the first switch 2F and the circuit 12, more specifically, between the first switch 2F and the diode 8F via the resistor R1. The input terminal 6I of the first detector 3F is connected to the power source 7 via the resistor R3. The output terminals 5E and 6E of the first detector 3F are both connected to the ground. The input terminal 5I of the second detector 3S is connected between the second switch 2S and the circuit 12, more specifically, between the second switch 2S and the diode 8S via the resistor R2. The input terminal 6I of the second detector 3S is connected to the power source 7 via the resistor R4. The output terminals 5E and 6E of the second detector 3S are both connected to the ground.

  The locations where the signal lines SL1 and SL2 are connected are the same as in the first embodiment. The control device 4 acquires the potential of the input terminal 6I of the first detector 3F, that is, the detected value SI1, and the potential of the input terminal 6I of the second detector 3S, that is, the detected values SI1 and SI2. The configuration of the control device 4 is the same as that of the first embodiment.

  In the power shut-off device 1b, when at least one of the first switch 2F and the second switch 2S is turned on, power is supplied from the power source 13 to the circuit 12. In addition, when both the first switch 2F and the second switch 2S are turned off, the power shutoff device 1b shuts off the power supply from the power supply 13 to the circuit 12.

  When the first switch 2F is turned on, the current from the power supply 13 flows through the first switch 2F, and then is shunted to the first detector 3F and the circuit 12. When a current flows through the first detector 3F, the light emitting diode 5 of the first detector 3F emits light and the phototransistor 6 is turned on, so that the detection value SI1 of the input terminal 6I of the first detector 3F is at L level. become. When the first switch 2F is off, the current from the power supply 13 does not flow through the first switch 2F, so the detection value SI1 at the input terminal 6I of the first detector 3F is at the H level.

  When the second switch 2S is turned on, the current from the power source 13 flows through the second switch 2S and then is shunted to the second detector 3S and the circuit 12. When a current flows through the second detector 3S, the light emitting diode 5 of the second detector 3S emits light and the phototransistor 6 is turned on, so that the detection value SI2 of the input terminal 6I of the second detector 3S is at L level. become. When the second switch 2S is off, the current from the power supply 13 does not flow through the second switch 2S, so the detection value SI2 at the input terminal 6I of the second detector 3S is at the H level.

  FIG. 10 is a diagram illustrating a relationship between the states of the first switch 2F and the second switch 2S according to the second embodiment and the detection values SI1 and SI2. As shown in FIG. 10, whether the first switch 2F and the second switch 2S are on or off is determined depending on whether the detection values SI1 and SI2 are at the H level or the L level. Based on the detection value SI1 of the first detector 3F and the detection value SI2 of the second detector 3S, the control device 4 determines whether the state of the switch circuit 2b, specifically, the first switch 2F and the second switch 2S are on or off. It is determined whether it is.

  In the first operation mode, the control device 4 sets the detection value SI1 of the first detector 3F and the detection value SI2 of the second detector 3S while alternately turning on or off the first switch 2F and the second switch 2S. Acquired to determine the state of the switch circuit 2b. That is, the control device 4 turns off the second switch 2S when the first switch 2F is on, and turns on the second switch 2S when the first switch 2F is off. Thus, the control device 4 exclusively turns on or off the first switch 2F and the second switch 2S in the first operation mode. The control device 4 determines the state of the switch circuit 2b, specifically, whether the first switch 2F and the second switch 2S are normal or abnormal from the detection values SI1 and SI2.

  In the second operation mode, the control device 4 turns off both the first switch 2F and the second switch 2S. When both the first switch 2F and the second switch 2S are turned off, power supply from the power supply 13 to the circuit 12 is interrupted.

  In the first operation mode, the control device 4 applies the operation signal SE1 to the first switch 2F, does not apply the operation signal SE1 to the second switch 2S, and sends the detection value SI1 from the first detector 3F to the second The detection value SI2 is acquired from the detector 3S. As shown in FIG. 10, if the detection value SI1 of the first detector 3F is L level and the detection value SI2 of the second detector 3S is H level, the first switch 2F and the second switch 2S operate normally. doing.

  Next, the control device 4 gives the operation signal SE2 to the second switch 2S, does not give the operation signal SE2 to the first switch 2F, and sends the detection value SI1 from the first detector 3F to the second detector 3S. The detection value SI2 is acquired. As shown in FIG. 10, if the detection value SI1 of the first detector 3F is H level and the detection value SI2 of the second detector 3S is L level, the first switch 2F and the second switch 2S operate normally. doing.

  If the first switch 2F is on, the current from the power source 13 flows to the circuit 12 through the first switch 2F even if the second switch 2S is off. Similarly, if the second switch 2S is on, the current from the power source 13 flows to the circuit 12 through the second switch 2S even if the first switch 2F is off. For this reason, the control device 4 can determine the state of the switch circuit 2b without interrupting the supply of power from the power supply 13 to the circuit 12, and therefore can determine the state of the switch circuit 2b while operating the circuit 12.

  In this way, the control device 4 can detect a state where the switch circuit 2b does not operate normally, that is, a state where the power supply from the power supply 13 to the circuit 12 cannot be interrupted in a state where power is supplied from the power supply 13 to the circuit 12. . Therefore, similarly to the first embodiment, the power shut-off device 1b can reduce the possibility of a failure occurring in the entire device control device 10 due to the failure of the switch circuit 2b. The control device 4 is the same as the first embodiment in that the control device 4 outputs the determination result RJ of the state of the switch circuit 2 during execution of the first operation mode.

  FIG. 11 is a timing chart of the operation signal SE1 applied to the first switch 2F and the operation signal SE2 applied to the second switch 2S in the second embodiment. The horizontal axis in FIG. 11 is time t. When both the first switch 2F and the second switch 2S are turned off, the power cut-off device 1b cuts off the supply of power from the power supply 13 to the circuit 12. That is, if both the first switch 2F and the second switch 2S are turned off while the control device 4 is executing the first operation mode, the operation of the circuit 12 may be stopped.

  In the first operation mode, the control device 4 provides a period during which both the first switch 2F and the second switch 2S are turned on, and alternately turns on or off the first switch 2F and the second switch 2S. Specifically, as shown in FIG. 11, the control device 4 provides a period in which both the operation signal SE1 and the operation signal SE2 are H. At time t1, the operation signal SE1 changes from L to H, but the operation signal SE2 maintains H. The operation signal SE2 changes from H to L at time t2 after time t1. At time t3, the operation signal SE2 changes from L to H, but the operation signal SE1 maintains H. The operation signal SE1 changes from H to L at time t4 after time t3. That is, both the first switch 2F and the second switch 2S are turned on from the time t1 to the time t2 and from the time t3 to the time t4.

  In the first operation mode, the control device 4 provides a period in which both the first switch 2F and the second switch 2S are turned on when the first switch 2F and the second switch 2S are alternately turned on or off. By this process, power is supplied from the power supply 13 to the circuit 12 during the period in which the first operation mode is being executed, so that the first switch 2F and the second switch 2S are alternately turned on or off. Also, the stop of the operation of the circuit 12 is avoided.

  As described above, the power shut-off device 1b according to the second embodiment has the same operations and effects as the power shut-off device 1 according to the first embodiment. Further, the power shut-off device 1b has an advantage that the configuration is simple because the fuse 14 is unnecessary. Further, the power shut-off device 1b does not need to pass a current necessary for fusing the fuse 14 to the first switch 2F and the second switch 2S. For this reason, the first switch 2F and the second switch 2S of the power shut-off device 1b only need to be able to pass a current having a required magnitude in the circuit 12. As described above, the power cutoff device 1b can use the first switch 2F and the second switch 2S having a lower rated current than the power cutoff device 1 according to the first embodiment. As a result, the power shut-off device 1b has an advantage that the choices of the first switch 2F and the second switch 2S are increased.

  The configurations shown in the first embodiment and the second embodiment are examples of the contents of the present invention, and can be combined with other known techniques and do not depart from the gist of the present invention. It is also possible to omit and change part of the configuration within the scope.

  1, 1b power shut-off device, 2F first switch, 2S second switch, 2, 2b switch circuit, 3F, 3Fa first detector, 3S, 3Sa second detector, 4 control device, 4AP processing circuit, 4C control unit 4J determination unit, 4P processor, 4M memory, 5 light emitting diode, 5a coil, 5E, 5Ea, 6E, 6Ea output terminal, 5I, 5Ia, 6I, 6Ia input terminal, 6 phototransistor, 6a switch, 7, 13 power supply, 8F, 8S diode, 10, 10b device control device, 11 drive circuit, 12 circuit, 14 fuse, 20 device, 21 actuator, 22 display device, IE abnormality occurrence information, R1, R2, R3, R4 resistance, RJ determination result, SE1, SE2 operation signal, SI1, SI2 detection value (potential), SL1, SL2 signal .

Claims (5)

In the power cutoff device that cuts off the power supplied from the power source to the circuit,
A switch circuit in which a first switch and a second switch are connected in series, branching from between the circuit and the fuse connected to the power source and the circuit;
A first detector that detects an H level when the first switch is turned on and detects an L level when the first switch is turned off ;
A second detector that detects an H level when the second switch is turned on and detects an L level when the second switch is turned off ;
A first value for detecting a detection value of the first detector or a detection value of the second detector while alternately turning on or off the first switch and the second switch to determine a state of the switch circuit A control device that executes an operation mode and a second operation mode that turns on both the first switch and the second switch;
Including
The controller is
The detection value of the first detector is H level and the detection value of the second detector is L level, or the detection value of the first detector is L level and the detection value of the second detector is H level. If it is, it will be determined that the first switch and the second switch are operating normally . In the power cutoff device that cuts off the power supplied from the power source to the circuit,
A switch circuit in which a first switch and a second switch are connected in parallel between the power source and the circuit;
A first detector that detects an L level when the first switch is turned on and detects an H level operating condition when the first switch is turned off ;
A second detector that detects an L level when the second switch is turned on and detects an H level operating condition when the second switch is turned off ;
The pre-Symbol determines the state of the switch circuit to obtain a detection value of the detection value or the second detector of the first detector while alternately turns on or off and the second switch and the first switch 1 A control device that executes the operation mode of the second and the second operation mode of turning off both the first switch and the second switch;
Only including,
The controller is
The detection value of the first detector is L level and the detection value of the second detector is H level, or the detection value of the first detector is H level and the detection value of the second detector is L level. If it is, it will be determined that the first switch and the second switch are operating normally . The controller is
The first operation mode, wherein the first switch and the second switch are alternately turned on or off by providing a period during which both the first switch and the second switch are turned on. Power shut-off device. The controller is
4. The power shutoff device according to claim 1, wherein a determination result of a state of the switch circuit is output during execution of the first operation mode. 5. The controller is
4. The power shut-off device according to claim 1, wherein information indicating a state of the circuit is acquired, and the second operation mode is executed when the information indicates an abnormality of the circuit. 5. .

Images