JP6662506B2 - Lighting equipment - Google Patents

Description

  The present invention relates to an illuminating device that causes an LED to emit light with power from an external commercial power supply, and emits light with an electric charge stored in a built-in electric double layer capacitor when an external power supply fails.

  2. Description of the Related Art A lighting device that emits light from a light-emitting unit such as an LED by power supplied from an external commercial power supply is widely known. Of those lighting devices, for example, in the case of a downlight installed on the ceiling of a bathroom, the bathroom has no windows, and especially when a power outage occurs at night, the bathroom becomes completely dark, and the bather gets out of the bathroom. It becomes difficult to move to the dressing room, wear clothes, and evacuate to the living room.

  Therefore, an electric double-layer capacitor was provided in the lighting device, and the electric double-layer capacitor was charged while the power supply from the commercial power supply was continued, and stored in the electric double-layer capacitor when a power failure occurred. 2. Description of the Related Art A lighting device that causes an LED to emit light by electric charges is known (for example, see Patent Document 1).

JP 2007-165016 A (paragraphs [0012] and [0022])

  In the above-described conventional device, it is necessary to boost the electric charge stored in the electric double layer capacitor to a voltage necessary for lighting the LED and supply the voltage to the LED. In such a case, a booster circuit is used. In general, the booster circuit does not operate when the input voltage is 0 volt, and does not operate when there is no input exceeding a predetermined voltage. Therefore, the voltage of the electric double layer capacitor is reduced by sequentially boosting the electric charge stored in the electric double layer capacitor by the booster circuit, and when the voltage is reduced to a predetermined voltage, the electric charge still remains in the electric double layer capacitor. Even in this state, the booster circuit cannot operate any more, causing a problem that the electric charge remaining in the electric double layer capacitor is wasted.

  In addition, by connecting a resistor in series with the electric double layer capacitor and raising the voltage of the electric double layer capacitor by the voltage divided by the resistance, the electric charge stored in the electric double layer capacitor is effectively used. However, as the electric double layer capacitor is consumed, the current flowing through the resistor decreases, and as a result, the voltage divided by the resistor decreases. The charge in the double layer capacitor cannot be fully utilized.

  In addition, since the withstand voltage of an electric double layer capacitor is generally low, when a resistor is not used, it is necessary to connect a plurality of electric double layer capacitors in series so as to output a voltage at which a booster circuit can operate, In such a configuration, in addition to the problem that the installation space is increased by using a plurality of electric double layer capacitors, there is a problem that the capacity of the entire electric double layer capacitor is reduced due to the series connection.

  In view of the above problems, an object of the present invention is to provide a lighting device that can effectively use the electric charge stored in an electric double layer capacitor to cause an LED to emit light during a power failure.

In order to solve the above problems, a lighting device according to the present invention includes a light emitting unit having an LED, rectifies AC power from a commercial power supply and supplies the rectified power to the light emitting unit, and stores output power of the power supply unit. a lighting device comprising the electric double layer capacitor, and a boosting circuit which boosts the charge which the commercial power is accumulated in the electric double layer capacitor during a power failure causing the LED to emit light is supplied to the light emitting unit, the booster circuit the minimum value of the input voltage operating as the lowest voltage with respect to the electric double layer capacitor, connecting a plurality of diodes such that the forward direction in series to the power supply direction to the booster circuit, the electric double layer when supplying a charge to the boost circuit from the capacitor, the voltage is divided across the series-connected plurality of diodes is set to be above the minimum voltage And it features.

  According to the above configuration, when the electric charge charged in the electric double layer capacitor is input to the booster circuit, the forward voltage (Vf) of the diode connected in series with the electric double layer capacitor is equal to the voltage of the electric double layer capacitor. And the electric double layer capacitor can continue to supply power to the booster circuit even when the voltage of the electric double layer capacitor approaches zero.

  If the number of the electric double layer capacitors is one, the installation space for the capacitors can be made as small as possible.

Further, the diode has a plurality of diodes by being connected in series, by appropriately selecting the number of diodes, and so as to adjust the raising amount for the electric double layer capacitor.

  As is apparent from the above description, according to the present invention, almost all of the power stored in the electric double layer capacitor can be used at the time of the occurrence of a power failure, so that the LED can emit light for a long time with a small number of electric double layer capacitors. You can continue.

FIG. 1 shows a configuration of an embodiment of the present invention.

  Referring to FIG. 1, reference numeral 1 denotes a commercial power supply, and 100 volt AC power from the commercial power supply 1 is input to a power supply unit 2. The power supply unit 2 rectifies 100 volt AC power into, for example, 30 volt DC power and supplies the rectified power to the LED light emitting unit 3. A plurality of LEDs connected in series and a circuit for controlling the current value of a series circuit of the LEDs are built in the LED light emitting unit 3, and 30 volt DC power is input from the power supply unit 2. Then, the built-in LED is configured to emit light with a predetermined brightness.

  An electric double layer capacitor 6 is provided to keep the LED of the LED light emitting unit 3 turned on when the commercial power supply 1 is out of power. In order to charge the electric double layer capacitor 6, a step-down circuit 4 for stepping down 30 volts output from the power supply unit 2 to a predetermined charging voltage is provided. The step-down circuit 4 is configured so that, when DC voltage of 30 volts is input, it is converted to DC power of 8 volts and output.

  In the present embodiment, only one electric double layer capacitor 6 is used. Generally, the rated voltage of the electric double layer capacitor is about 2.7 volts. Therefore, if 8 volts is applied directly to charge the electric double layer capacitor 6, the electric double layer capacitor 6 will be damaged. Therefore, a plurality of diodes 71 were connected in series to the electric double layer capacitor 6 so as to be in the forward direction during charging.

  Since the forward voltage (Vf) of one diode is about 0.6 volt, if the diode 71 is composed of nine diodes, the forward voltage of the entire diode 71 becomes 5.4 volt, Even if a voltage of 8 volts is output, only 2.6 volts is applied to the electric double layer capacitor 6. Therefore, the electric double layer capacitor 6 is not damaged.

  Next, when a power failure occurs, the switch 51 composed of a switching element such as a relay or a transistor is turned on. Then, the charge charged in the electric double layer capacitor 6 is boosted to 30 volts by the booster circuit 5 and supplied to the LED light emitting unit 3. As a result, even if the commercial power source 1 loses power, the LED light emitting unit 3 can continue to emit light.

  However, the booster circuit 5 stops operating when the input voltage becomes 3 volts or less. Therefore, even if one electric double layer capacitor having a rated voltage of 2.7 volts is connected to the input section of the booster circuit 5, the booster circuit 5 does not operate.

  Therefore, the diode 72 is connected in series so as to be in a forward direction with respect to the power supply direction to the booster circuit 5. If the diode 72 is constituted by connecting nine diodes in series similarly to the diode 71, the forward voltage of the diode 72 becomes 5.4 volts in the same manner as described above, and the electric double layer capacitor 6 discharges. Even if the voltage of the electric double-layer capacitor 6 has dropped, most of the electric charges charged in the electric double-layer capacitor 6 flow to the booster circuit 5, and even if the voltage of the electric double-layer capacitor 6 becomes almost 0 volt, The circuit 5 will have a 5.4 volt input. Therefore, almost all of the electric charge charged in the electric double layer capacitor 6 can be passed to the booster circuit 5 without being left.

  The present invention is not limited to the above-described embodiment, and various changes may be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Commercial power supply 2 Power supply part 3 Light emitting part 4 Step-down circuit 5 Step-up circuit 6 Electric double layer capacitor 51 Switch 71 Diode 72 Diode

Claims (2)

A power supply for rectifying AC power from a commercial power supply and supplying the light to the light-emitting unit; an electric double-layer capacitor for storing output power of the power supply; A booster circuit for boosting the charge stored in the double-layer capacitor and supplying the boosted charge to the light emitting unit to emit an LED, wherein the lowest value of the input voltage at which the booster circuit operates is regarded as the minimum voltage, A plurality of diodes are connected in series to the double-layer capacitor so as to be in a forward direction with respect to the power supply direction to the booster circuit, and when supplying electric charge from the electric double-layer capacitor to the booster circuit, A lighting device, wherein a voltage divided across both ends of a plurality of diodes connected in series is set to be equal to or higher than the minimum voltage .   The lighting device according to claim 1, wherein the number of the electric double layer capacitors is one.

Images