JP2022107412A - Lighting unit and emergency lighting device - Google Patents

Abstract

To obtain a lighting unit and an emergency lighting device that can monitor a voltage of an external power supply in detail.SOLUTION: A lighting unit includes: a regular power supply circuit that is powered by an external power supply to charge a battery; an emergency power supply circuit that lights up a light source unit by supplying power from the battery when the external power supply is in a power failure state; and a control unit that controls the emergency power supply circuit. When the voltage of the external power supply is less than a first threshold value, the control unit determines the state of the external power supply to be a power failure state. When the voltage of the external power supply is equal to or higher than the first threshold value and less than a second threshold value larger than the first threshold value, the control unit determines the state of the external power supply to be a voltage drop state. When the voltage of the external power supply is equal to or higher than the second threshold value, the control unit determined the state of the external power supply to be a normal state.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to lighting units and emergency lighting devices.

Patent Document 1 discloses a luminaire including a power supply circuit, a voltage detection circuit, a charging circuit, a lighting circuit, and a storage battery. The power supply circuit produces output power from the input power supplied by the DC voltage source. The voltage detection circuit outputs a detection signal according to the height of the input voltage input from the DC voltage source and the threshold voltage. When the voltage detection circuit outputs a detection signal indicating that the input voltage is higher than the threshold voltage, the charging circuit charges the storage battery with the output power of the power supply circuit. When the voltage detection circuit outputs a detection signal indicating that the input voltage is lower than the threshold voltage, the lighting circuit uses the storage battery as a power source to light the light source.

Japanese Patent No. 6562354

In Patent Document 1, the information about the input voltage used for controlling the lighting equipment is only the information about the high and low of the input voltage and the threshold voltage. Therefore, sufficient control may not be possible.

The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to obtain a lighting unit and an emergency lighting device capable of monitoring the voltage of an external power source in detail.

The lighting unit according to the present disclosure includes a regular power supply circuit that is supplied with power from an external power source to charge a battery, and an emergency power supply circuit that is supplied with power from the battery to light a light source unit when the external power supply is in a power failure state. And a control unit that controls the emergency power supply circuit, the control unit determines that the state of the external power supply is a power failure state when the voltage of the external power supply is less than the first threshold value, and the external power supply. When the voltage of is equal to or higher than the first threshold value and less than the second threshold value larger than the first threshold value, the state of the external power supply is determined to be a voltage drop state, and when the voltage of the external power supply is equal to or higher than the second threshold value, the external power supply is determined. Determine the power status as normal.

In the lighting unit according to the present disclosure, the control unit uses the first threshold value and the second threshold value to discriminate between a power failure state, a voltage drop state, and a normal state. Therefore, the control unit can monitor the voltage of the external power supply in detail.

It is a circuit block diagram of the emergency lighting apparatus which concerns on Embodiment 1. FIG. It is a figure which shows the structure of the power failure detection circuit which concerns on Embodiment 1. FIG. It is a figure which shows the waveform of the voltage across the capacitor which concerns on Embodiment 1 and the voltage applied to the control part. It is a figure which shows the relationship between the input voltage to the ordinary power supply circuit which concerns on a comparative example, and the drain current of a switching element.

The lighting unit and the emergency lighting device according to each of the present embodiments will be described with reference to the drawings. The same or corresponding components may be designated by the same reference numerals and the description may be omitted. The present disclosure is not limited to the embodiments described below. In addition, when referring to the connection below, it shall include an electrical connection.

Embodiment 1.
FIG. 1 is a circuit block diagram of the emergency lighting device 100 according to the first embodiment. The emergency lighting device 100 includes a lighting unit 10 and a light source unit 30. The light source unit 30 includes a light source for ensuring brightness in an emergency. The light source is, for example, an LED. By configuring the light source unit 30 with LEDs, the energy consumption of the emergency lighting device 100 can be suppressed.

The emergency lighting device 100 is equipped with a battery 50 for lighting the light source unit 30. The lighting unit 10 is supplied with electric power from the external power supply AC to charge the battery 50. The external power supply AC is an AC power supply. The battery 50 supplies electric power to the light source unit 30 in an emergency such as a power failure to light the light source unit 30. The battery 50 may be a rechargeable battery. The battery 50 is a secondary battery such as a Ni-Cd battery, a nickel-metal hydride battery, or a lithium-ion battery.

The lighting unit 10 includes a diode bridge 1, a regular power supply circuit 2, a charging circuit 3, a power failure detection circuit 5, an emergency power supply circuit 6, and a control unit 7.

The diode bridge 1 converts alternating current into direct current. The output of the diode bridge 1 is connected to the regular power supply circuit 2. The low potential side of the output of the diode bridge 1 is connected to the grounding terminal.

The regular power supply circuit 2 is composed of an insulated flyback circuit. The normal power supply circuit 2 is supplied with electric power from the external power supply AC during normal use to charge the battery 50. Here, the term "civil time" indicates a state in which the external power supply AC is not in a power failure state or a pseudo power failure state. Unless otherwise specified in the following description, the power failure state or the pseudo power failure state are collectively referred to as a power failure state. The regular power supply circuit 2 includes capacitors 11, 13, 24, resistors 12, 17, 22, 23, a transformer 14, and a switching element 15. Further, the regular power supply circuit 2 includes a control IC (Integrated Circuit) 16, a photocoupler 18, a pseudo power failure generation circuit 19, a diode 20, and an electrolytic capacitor 21.

In the regular power supply circuit 2, a capacitor 11 is connected in parallel with the output of the diode bridge 1 in order to reduce the ripple due to the full-wave waveform of the external power supply AC and switching. One end of the resistor 12 and one end of the primary side of the transformer 14 are connected to the positive electrode of the capacitor 11.

The first terminal of the switching element 15 is connected to the other end of the primary side of the transformer 14. The second terminal of the switching element 15 is connected to the negative electrode of the capacitor 11. The control terminal of the switching element 15 is connected to the control IC 16. The control terminal is a terminal for switching between the first terminal and the second terminal. The control IC 16 controls the regular power supply circuit 2.

The switching element 15 is, for example, a MOSFET (Metal-Oxide-Semiconductor Field-Effective Transistor). When the switching element 15 is a MOSFET, the first terminal is a drain terminal, the second terminal is a source terminal, and the control terminal is a gate terminal. In the switching element 15, the first terminal is connected to the transformer 14, the second terminal is connected to the grounding terminal, and the control terminal is connected to the control IC 16.

The control IC 16 is, for example, a DCDC driver. The control IC 16 drives the switching element 15. The series circuit formed by the resistor 12 and the capacitor 13 is connected in parallel with the capacitor 11 to supply power to the control IC 16.

A photocoupler 18 is connected to the control IC 16 via a resistor 17. The resistor 17 and the photocoupler 18 are provided to input information on the secondary side of the transformer 14 to the control IC 16.

The pseudo power failure generation circuit 19 is a circuit capable of generating a pseudo power failure state. The pseudo power failure generation circuit 19 includes a pseudo power failure inspection switch, a remote control inspection button, and the like. The pseudo power failure generation circuit 19 can stop the switching in the control IC 16 triggered by, for example, turning on the pseudo power failure inspection switch. As a result, the pseudo power failure generation circuit 19 can create a pseudo power failure state. Therefore, it is possible to confirm whether or not the emergency lighting device 100 operates normally when the external power supply AC has a power failure.

The anode of the diode 20 is connected to one end of the flyback winding on the secondary side of the transformer 14. The diode 20 is connected in series with the secondary side of the transformer 14 and is provided to transmit a stable voltage to the output side. The positive electrode of the electrolytic capacitor 21 is connected to the cathode of the diode 20. The negative electrode of the electrolytic capacitor 21 is connected to a grounding terminal.

In the grounding path of the normal power supply circuit 2, the primary side and the secondary side of the transformer 14 are insulated by the capacitor 24.

The regular power supply circuit 2 includes a regular power supply output voltage detection unit. The normal power supply output voltage detection unit is composed of a resistance 22 and a resistance 23 connected in series. The normal power supply output voltage detection unit is connected in parallel with the electrolytic capacitor 21. The divided values of the resistance 22 and the resistance 23 are input to the microcomputer which is the control unit 7. As a result, the control unit 7 detects the output voltage of the regular power supply circuit 2.

The control unit 7 calculates a target value according to the output voltage of the regular power supply circuit 2. After that, the control unit 7 outputs a voltage corresponding to the target value from the output terminal. This voltage is transmitted to the primary side via the photocoupler 18. The primary side of the photocoupler 18 is connected to the control IC 16. The control IC 16 receives a target value from the control unit 7 via the photocoupler 18. The control IC 16 controls the switching element 15 on and off so that the target value and the output voltage of the regular power supply circuit 2 match. As a result, the feedback of the regular power supply circuit 2 which is an isolated flyback circuit is realized.

A battery 50 is connected to the output of the regular power supply circuit 2 via the charging circuit 3. The output voltage of the regular power supply circuit 2 is supplied to the battery 50 via the charging circuit 3. As a result, the battery 50 is charged.

The emergency power supply circuit 6 is composed of a step-up switching circuit. The emergency power supply circuit 6 operates in an emergency such as a power failure of the external power supply AC, boosts the output voltage of the battery 50, and lights the light source unit 30. That is, in the emergency power supply circuit 6, when the external power supply AC is in a power failure state, power is supplied from the battery 50, which is a DC power supply, to light the light source unit 30.

A capacitor 34 is connected in parallel to the input end of the emergency power supply circuit 6. The positive electrode of the battery 50 and one end of the coil 53 are connected to the positive electrode of the capacitor 34. The negative electrode of the capacitor 34 is connected to the grounding terminal. The other end of the coil 53 is connected to the anode of the diode 54. The cathode of the diode 54 is connected to the positive electrode of the capacitor 58. The negative electrode of the capacitor 58 is connected to the negative electrode of the capacitor 34. That is, a series circuit in which the coil 53, the diode 54, and the capacitor 58 are connected in this order is connected in parallel with the capacitor 34.

A switching element 55 is connected between the connection point of the coil 53 and the diode 54 and the grounding terminal. The first terminal of the switching element 55 is connected to the anode of the diode 54. The second terminal of the switching element 55 is connected to the negative electrode of the capacitor 58. The control terminal of the switching element 55 is connected to the control unit 7. The switching element 55 is, for example, a MOSFET.

The anode side of the light source unit 30 is connected to the positive electrode of the capacitor 58. One end of the resistor 59 is connected to the cathode side of the light source unit 30. The other end of the resistor 59 is connected to the negative electrode of the capacitor 58. In FIG. 1, the light source unit 30 has two LEDs that are light sources. Not limited to this, the number of light sources included in the emergency lighting device 100 may be one or more.

The power failure detection circuit 5 is a circuit that detects a power failure state of the external power supply AC. The power failure detection circuit 5 is connected in parallel with the capacitor 11. The power failure detection circuit 5 detects the state of the external power supply AC from the voltage across the capacitor 11. The power failure detection circuit 5 is connected to the control unit 7. When the power failure detection circuit 5 detects a voltage drop in the external power supply AC, it transmits a signal indicating that the external power supply AC is in the voltage drop state to the control unit 7. As a result, the control unit 7 reduces the charging current of the battery 50, which is the output of the regular power supply circuit 2. When the power failure detection circuit 5 detects a power failure of the external power supply AC, it transmits a signal indicating that the external power supply AC is in a power failure state to the control unit 7. Upon receiving the signal from the power failure detection circuit, the control unit 7 operates the emergency power supply circuit 6.

The emergency power supply circuit 6 includes an emergency power supply output voltage detection unit. The emergency power supply output voltage detection unit is composed of a resistance 56 and a resistance 57 connected in series. The emergency power supply output voltage detection unit is connected in parallel with the capacitor 58. The divided values of the resistance 56 and the resistance 57 are input to the control unit 7. As a result, the control unit 7 detects the output voltage of the emergency power supply circuit 6.

The emergency power supply circuit 6 includes an output current detection unit. The output current detection unit is composed of a resistor 59 connected to the cathode side of the light source unit 30. When the emergency power supply circuit 6 operates, a voltage obtained by boosting the output voltage of the battery 50 is applied to the capacitor 58. The voltage applied to the capacitor 58 is the output voltage of the emergency power supply circuit 6. A voltage corresponding to the current flowing through the light source unit 30 is generated in the resistor 59. The voltage generated in the resistor 59 is input to the control unit 7. As a result, the control unit 7 detects the output current of the emergency power supply circuit 6.

The control unit 7 sets a target value of the output current according to the output voltage detected by the emergency power supply output voltage detection unit. The control unit 7 turns the switching element 55 on and off so that the target value is realized. In this way, the control unit 7 controls the emergency power supply circuit 6 with constant power feedback. From the above, the electric power of the light source unit 30 is controlled to be constant.

Subsequently, the control unit 7 will be described. The control unit 7 is composed of, for example, a microcomputer. The microcomputer includes a CPU that performs various operations, a memory, and a timer. The memory is composed of, for example, a non-volatile memory.

The control unit 7 compares the voltage value of the external power supply AC input from the power failure detection circuit 5 with the pre-programmed threshold value, and determines the state of the external power supply AC. The threshold value is stored in the memory of the microcomputer. The control unit 7 may read the threshold value from the memory and compare it with the voltage value of the external power supply AC to determine the state of the external power supply AC or the battery 50. Hereinafter, the control unit 7 will be described as assuming that the first threshold value and the second threshold value are stored in the memory in advance.

FIG. 2 is a diagram showing a configuration of a power failure detection circuit 5 according to the first embodiment. The power failure detection circuit 5 includes resistors 91, 92, 95, 96, a Zener diode 93, a photocoupler 94, and a switching element 97.

A resistance 91 and a resistance 92 connected in series are connected to both ends of the capacitor 11. The cathode of the Zener diode 93 is connected to the connection point between the resistance 91 and the resistance 92. The control terminal of the switching element 97 is connected to the anode of the Zener diode 93.

The switching element 97 is, for example, a transistor. When the switching element 97 is a transistor, the first terminal is a collector, the second terminal is an emitter, and the control terminal is a base.

A voltage from the power supply Vcc1 is applied to the first terminal of the switching element 97 via the resistance 95 and the primary side of the photocoupler 94. The second terminal of the switching element 97 is connected to the grounding terminal on the primary side of the regular power supply circuit 2.

The power supply Vcc2, the secondary side of the photocoupler 94, and the resistor 96 are connected in series in this order. The end of the resistor 96 on the opposite side to the photocoupler 94 is connected to the grounding terminal on the secondary side of the normal power supply circuit 2. The voltage generated in the resistor 96 is applied to the control unit 7 as a detection voltage.

FIG. 3 is a diagram showing waveforms of the voltage across the capacitor 11 and the voltage applied to the control unit 7 according to the first embodiment. The method in which the power failure detection circuit 5 detects the voltage of the external power supply AC will be described in detail.

The external power supply AC is rectified by the diode bridge 1 and applied to both ends of the capacitor 11. The voltage across the capacitor 11 is divided by the resistor 91 and the resistor 92, and further dropped by the Zener diode 93. A switching element 97 is connected to the anode of the Zener diode 93. Therefore, when the voltage across the capacitor 11 reaches the voltage designed by the resistor 91, the resistor 92, and the Zener diode 93, the switching element 97 is turned on. When the switching element 97 is turned on, a current flows from the power supply Vcc1 to the photocoupler 94 via the resistor 95. A power supply Vcc2 is connected to the secondary side of the photocoupler 94. Therefore, a current flows from the power supply Vcc2 to the secondary side of the photocoupler 94 and the resistance 96 in this order, and a voltage is generated in the resistance 96.

That is, as shown in FIG. 3, when the voltage of the external power supply AC is large, the on-time of the switching element 97 becomes long, and when the voltage of the external power supply AC is small, the on-time of the switching element 97 becomes short. The control unit 7 detects the on-time of the switching element 97 as a voltage generated in the resistance 96.

As described above, in the present embodiment, the power failure detection circuit 5 has a switching element 97 whose on-time changes according to the voltage of the external power supply AC. Specifically, a full-wave rectified wave corresponding to the external power supply AC is input to the power failure detection circuit 5, and the switching element 97 is turned on when the voltage value of the full-wave rectified wave is larger than a predetermined value. It becomes. Therefore, the control unit 7 can detect the voltage of the external power supply AC according to the on-time of the switching element 97.

If the capacity of the capacitor 11 is large, the phases of the voltage and the current are out of phase due to the influence of charging and discharging by the capacitor 11. Therefore, the power factor may decrease. Therefore, in order to improve the power factor, it is preferable to reduce the capacitance of the capacitor 11. As a result, the voltage across the capacitor 11 can be a full-wave rectified wave. The full-wave rectified wave is also called the pulsating voltage.

Next, a method for the control unit 7 to determine a power failure state, a voltage drop state, and a normal state will be described. The control unit 7 stores the first threshold value and the second threshold value in the memory in advance. The second threshold is larger than the first threshold.

In the power failure detection circuit 5, the larger the voltage of the external power supply AC, the longer the on-time of the switching element 97. The power failure detection circuit 5 transmits a signal corresponding to the on-time of the switching element 97 to the control unit 7. The control unit 7 compares the on-time of the switching element 97 with the first threshold value and the second threshold value, and determines the state of the external power supply AC. For example, when the voltage of the external power supply AC is less than the first threshold value, the control unit 7 determines the state of the external power supply AC as a power failure state. For example, when the voltage of the external power supply AC is equal to or more than the first threshold value and less than the second threshold value, the control unit 7 determines the state of the external power supply AC as the voltage drop state. For example, when the voltage of the external power supply AC is equal to or higher than the second threshold value, the control unit 7 determines that the state of the external power supply AC is a normal state.

In the emergency lighting device 100 of the present embodiment, the control unit 7 uses the first threshold value and the second threshold value to discriminate between a power failure state, a voltage drop state, and a normal state. Therefore, the control unit 7 can monitor the voltage of the external power supply AC in detail as compared with the case where only the power failure state and the normal state are discriminated. In the normal state, the control unit 7 controls the regular power supply circuit 2 to charge the battery 50. Further, the control unit 7 controls the emergency power supply circuit 6 to light the light source unit 30 in a power failure state. Next, an example of control in the voltage drop state will be described.

FIG. 4 is a diagram showing the relationship between the input voltage Vin to the regular power supply circuit 2 and the drain current Id of the switching element 15 according to the comparative example. The waveforms of the input voltage Vin and the drain current Id when the external power supply AC is lowered will be described in detail.

The control IC 16 operates at a fixed frequency. Therefore, in order to generate stable output power, the control IC 16 controls the on-time of the switching element 15 to be short when the input voltage Vin is large and the on-time of the switching element 15 to be long when the input voltage Vin is small.

As a comparative example of this embodiment, it is assumed that the control IC 16 keeps the output power of the regular power supply circuit 2 constant when the external power supply AC is lowered. At this time, there is a possibility that the on-time exceeds the cycle of the switching frequency generated by the control IC 16 near the bottom of the input voltage Vin. That is, there is a possibility that accurate switching control cannot be performed near the bottom of the input voltage Vin.

Further, in general, in a control IC, a maximum on-time or a maximum ONDuty may be set internally in order to prevent heat generation and failure of the switching element. As a result, switching may become more difficult near the bottom of the input voltage Vin.

Further, in order to supply a predetermined power to the output, it may be necessary to supply the power that could not be supplied near the bottom of the input voltage Vin near the peak of the input voltage Vin. That is, the on-time may be longer than expected near the peak of the input voltage Vin, and the control may become unstable.

From the above, if the power factor is improved by using the capacitor 11 having a small capacity, the input voltage Vin may become unstable. Therefore, the detected value of the input voltage Vin in the control IC 16 may vary.

On the other hand, when the control unit 7 of the present embodiment determines that the state of the external power supply AC is the voltage drop state, the output power of the regular power supply circuit 2 is lowered as compared with the case where the external power supply AC is in the normal state. Specifically, the control unit 7 lowers the target value of the output voltage of the regular power supply circuit 2. By reducing the output power of the regular power supply circuit 2, the on-time of the switching element 15 can be shortened. Therefore, when the external power supply AC decreases and the on-time increases, it is possible to prevent the on-time from exceeding the cycle of the switching frequency. Therefore, accurate switching can be performed near the bottom of the input voltage Vin. Further, it is not necessary to make up for the shortage of power near the peak of the input voltage Vin. Therefore, the regular power supply circuit 2 can be controlled stably. Further, the voltage across the capacitor 11 can be stabilized, and the voltage of the external power supply AC can be accurately monitored. In particular, in the present embodiment, the voltage of the external power supply AC can be accurately monitored without adding new parts to the luminaire. Therefore, the emergency lighting device 100 can be miniaturized.

Emergency lighting devices are used to illuminate the room so that people in the area can safely evacuate in the event of a disaster such as a fire or earthquake in a place where an unspecified number of people gather, or a power outage that occurs in the event of an accident. Used for. The emergency lighting device is supplied with electric power from an external power source to charge the battery during normal use, and supplies electric power from the charged battery to light the light source in an emergency when power is not supplied from the external power source AC. Emergency lighting devices are also called emergency lights. Such emergency lighting devices may specify the required operation. This provision is, for example, "emergency lighting equipment technology" (JIL5501: 2017 revised supplement) established by the Japan Lighting Industry Association. The emergency lighting device needs to switch to emergency lighting at, for example, 40% voltage or more and less than 85% voltage with respect to the minimum value in the rated voltage range.

In the present embodiment, even when the operation required by the emergency lighting device 100 is specified, the voltage of the external power supply AC can be monitored in detail, and accurate operation can be realized.

The control unit 7 of the present embodiment discriminates between a power failure state, a voltage drop state, and a normal state according to the on-time of the switching element 97. Not limited to this, the control unit 7 may discriminate between a power failure state, a voltage drop state, and a normal state by another method. Further, the control IC 16 may discriminate between a power failure state, a voltage drop state, and a normal state, and control the output power of the regular power supply circuit 2. Each function of the control unit 7 and the control IC 16 may be realized by either the control unit 7 or the control IC 16, or may be realized by one control unit.

Further, the control in the voltage drop state is not limited to reducing the output power of the regular power supply circuit 2. When the control unit 7 determines that the state of the external power supply AC is the voltage drop state, another control may be performed.

As a modification of the present embodiment, the control unit 7 may determine the state of the external power supply AC as a power failure state when the voltage of the external power supply AC is less than the first threshold value for a predetermined time. Further, the control unit 7 may determine the state of the external power supply AC as the voltage drop state when the state of the voltage of the external power supply AC is equal to or higher than the first threshold value and less than the second threshold value continues for a predetermined time. Further, the control unit 7 may determine the state of the external power supply AC as a normal state when the state of the voltage of the external power supply AC of the second threshold value or higher continues for a predetermined time. As a result, it is possible to prevent the control from being switched due to a temporary voltage fluctuation. The above-mentioned predetermined time is, for example, a time considering a momentary power failure or a momentary voltage drop.

The technical features described in this embodiment may be used in combination as appropriate.

1 Diode bridge, 2 Regular power supply circuit, 3 Charging circuit, 5 Power failure detection circuit, 6 Emergency power supply circuit, 7 Control unit, 10 Lighting unit, 11 Condenser, 12 Resistance, 13 Condenser, 14 Transformer, 15 Switching element, 16 Control IC, 17 resistance, 18 photocoupler, 19 pseudo power failure generation circuit, 20 diode, 21 electrolytic capacitor, 22 resistance, 23 resistance, 24 capacitor, 30 light source, 34 capacitor, 50 battery, 53 coil, 54 diode, 55 switching element , 56 resistance, 57 resistance, 58 capacitor, 59 resistance, 91 resistance, 92 resistance, 93 Zener diode, 94 photocoupler, 95 resistance, 96 resistance, 97 switching element, 100 emergency lighting device, AC external power supply

Claims (8)

A regular power supply circuit that is powered by an external power source to charge the battery,
An emergency power supply circuit that lights up the light source unit by supplying power from the battery when the external power supply is in a power failure state.
A control unit that controls the emergency power supply circuit and
With
When the voltage of the external power supply is less than the first threshold value, the control unit determines the state of the external power supply as the power failure state, and the voltage of the external power supply is equal to or higher than the first threshold value and larger than the first threshold value. A lighting unit characterized in that when it is less than two threshold values, the state of the external power supply is determined to be a voltage drop state, and when the voltage of the external power supply is equal to or more than the second threshold value, the state of the external power supply is determined to be a normal state. The first aspect of claim 1, wherein when the control unit determines that the state of the external power supply is the voltage drop state, the output power of the normal power supply circuit is lowered as compared with the case where the external power supply is in the normal state. Lighting unit. A power failure detection circuit having a switching element whose on-time changes according to the voltage of the external power supply is provided.
The lighting unit according to claim 1 or 2, wherein the control unit discriminates between the power failure state, the voltage drop state, and the normal state according to the on-time of the switching element. A full-wave rectified wave corresponding to the external power supply is input to the power failure detection circuit.
The lighting unit according to claim 3, wherein the switching element is turned on when the voltage value of the full-wave rectified wave is larger than a predetermined value. Claims 1 to claim 1, wherein the control unit determines the state of the external power supply as the power failure state when the state in which the voltage of the external power supply is less than the first threshold value continues for a predetermined time. The lighting unit according to any one of 4. The control unit is characterized in that when the voltage of the external power supply is equal to or higher than the first threshold value and less than the second threshold value continues for a predetermined time, the state of the external power supply is determined to be the voltage drop state. The lighting unit according to any one of claims 1 to 5. Claims 1 to claim 1, wherein the control unit determines the state of the external power source as the normal state when the state of the voltage of the external power source is equal to or higher than the second threshold value continues for a predetermined time. The lighting unit according to any one of 6. The lighting unit according to any one of claims 1 to 7.
With the light source unit
An emergency lighting device characterized by being equipped with.

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