JP2019140050A - LED lighting device - Google Patents

Abstract

To solve a problem in which, after a lighting switch is turned on, in a case in which a resistance value connected in parallel with an LED is read to determine a model of a lamp in which the LED is incorporated before a voltage applied to both ends of an LED reaches Vt, and for example, when the lighting switch is turned on immediately after being turned off, and both end voltages across the LED is not sufficiently lower than a predetermined threshold set to a voltage lower than Vt at the time of model identification, and the model identification cannot be performed until both end voltages falls below the threshold value.SOLUTION: Voltage reset means is provided for discharging a voltage applied to a lamp and forcibly returning to a state below a threshold value once when the voltage applied to the lamp exceeds the threshold value when the lamp determination is started.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an LED lighting device in which a plurality of types of lamps incorporating LEDs are detachably connected to a power supply unit.

  In order to cause the LED to emit light, it is necessary to apply a voltage higher than a forward drop voltage (hereinafter simply referred to as Vf) between the anode (anode) and the cathode (cathode). If the applied voltage is Vf or less, no current flows through the LED, and therefore no light is emitted. When the applied voltage exceeds Vf, current begins to flow through the LED, and the LED starts to emit light. The brightness, that is, the brightness of the LED increases as the current value increases. For this reason, in the illuminating device using LED, when increasing the whole brightness | luminance, several LED is connected in series and it is comprised so that the electric current value which flows into each LED may become the same.

  However, if the current value is increased, the LED generates heat and the deterioration rate increases, so the current value flowing through the LED is controlled to a constant value, and the current value is increased or decreased when increasing or decreasing the brightness of the entire lamp according to the model. Instead, it is handled by increasing or decreasing the number of LEDs for each model.

  Therefore, by creating a plurality of types of lamps with different numbers of built-in LEDs and configuring the lamps to be detachably connectable to a separate power supply unit, a lamp having a desired brightness is selected and used. The lamp which can be used is proposed (for example, refer patent document 1).

  In this device, since the lamp is detachable from the power supply unit, in order to detect whether the lamp is connected, a resistor is provided in parallel to the LED in the lamp, and the resistance in the power supply unit Whether or not the lamp is connected is detected from the partial pressure at the intermediate point with the resistance in the lamp.

  In what is described in Patent Document 1, the current value flowing in the LED is controlled to be the same current value regardless of which of a plurality of types of lamps having different numbers of LEDs is connected. The resistance for the connection confirmation provided in the lamp is the same resistance value regardless of the lamp model. Therefore, in what was described in the said patent document 1, the kind of connected lamp cannot be discriminate | determined and it is not necessary to discriminate | determine.

  In the thing of the said patent document 1, since the value of the electric current sent to LED was constant regardless of the lamp of any model, it was not necessary to discriminate the model, but the current value was changed according to the model of the lamp. When it is necessary to do so, the configuration described in Patent Document 1 cannot be used.

  Therefore, a resistor having a resistance value set in advance for each type is connected in parallel to the series circuit of the LEDs in each lamp, and in the state where the lamp is not connected to the power supply unit, the lamp connecting portion. When the lamp is connected to a voltage controller that limits the voltage applied to the forward voltage drop (Vf) of all types of lamps, the lamp is provided with a voltage applied to the lamps of Vf or less. A plurality of types of lamps having different current values flowing through the LEDs by determining the type of the lamp from the resistance value of the resistor and performing constant current control so that a current corresponding to the type of the connected lamp flows through the LED. LED illuminating devices have been proposed that can determine the type of lamp and allow a current to flow through the lamp at a current value set for each lamp when the lamp is detachably connected to the power supply unit (for example, Patent Documents). 2).

Japanese Patent Laying-Open No. 2012-59422 (FIG. 1) Japanese Patent Laying-Open No. 2015-133229 (FIG. 4)

  In the conventional LED lighting device described in Patent Document 2, when the lighting switch is turned on and turned on again after the lighting switch is turned off, the lamp is replaced while the lighting is turned off. Whether or not the LED lighting device side can not be detected in advance before the on / off switch is turned on. Therefore, the LED lighting device is set so as to determine the lamp every time the on / off switch is turned on.

  On the other hand, the power supply unit is provided with a smoothing capacitor particularly when rectifying AC power from the outside and converting it to DC power. Therefore, the voltage applied to the lamp does not drop sufficiently immediately after the lighting switch is turned off. Therefore, if the lighting switch is turned on again in a short time after the lighting switch is turned off, In some cases, the voltage applied to the lamp is higher than Vf, or even if the voltage is lower than Vf, the voltage is too high to determine the lamp.

  In such a case, the lamp type cannot be determined until the voltage stored in the capacitor is spontaneously discharged and the voltage applied to the lamp drops below a predetermined threshold value. Even if is turned on, there will be a situation where the lamp does not light up immediately.

  Therefore, in view of the above-described problems, the present invention provides an LED lighting device in which a lamp can be turned on immediately even when the on / off switch is turned off and then turned on again in a short time. This is the issue.

  In order to solve the above problems, an LED lighting device according to the present invention includes a detachable lamp in which a plurality of LEDs are connected in series, and supplies power to the lamp when the lamp is detachably connected. An LED lighting device including a power supply unit that emits an LED of a lamp, the lamp having a plurality of types of lamps having different current values to be passed through the LED, and a resistance having a resistance value set in advance for each type Are connected in parallel to the series circuit of the LEDs in each lamp, and the voltage applied to the lamp connection in the state where the lamp is not connected to the power supply section in the order of all kinds of lamps. When a voltage control unit that limits the voltage to a voltage below a predetermined threshold set below a directional voltage drop (Vf) and a lamp are connected, the voltage applied to the lamp is increased and the lamp exceeds the threshold before reaching Vf. Of the above resistance The type of the lamp is determined from the resistance value, and constant current control is performed so that the current corresponding to the type of the connected lamp flows to the LED. When the determination of the lamp is started, the voltage applied to the lamp is When the threshold value is exceeded, voltage reset means is provided for discharging the voltage applied to the lamp and forcibly returning it to a state below the threshold value.

  According to the above configuration, by providing the voltage reset means, when the voltage applied to the lamp exceeds the threshold at the time when the determination of the lamp is started, the voltage is immediately reduced to the threshold or less to thereby reduce the lamp. Discrimination and lighting can be performed immediately.

  The resistor incorporated in the lamp is used at the time of constant current control. However, when the model is discriminated, since the applied voltage is Vf or less, the divided voltage becomes low.

  Therefore, the constant current control and the determination of the type of the lamp are performed by the partial pressure generated by connecting the resistor provided in the lamp and the resistor provided in the power supply unit in series, and the resistance value in the power supply unit is determined. It is desirable to switch the resistance value so that the resistance value when determining the lamp is larger than the resistance value when performing constant current control, and to increase the voltage dividing ratio when determining the type of the lamp .

  As is clear from the above description, when the present invention is turned on, the voltage applied to the lamp is discharged and lowered below the threshold value, for example, immediately after the lighting switch is turned off. Even in such a case, it is possible to immediately determine the lamp and turn on the lamp.

The figure which shows the bathroom where the lamp by this invention is applied Block diagram showing the overall structure of the lamp Block diagram showing the internal structure of the power supply Diagram showing the configuration of the voltage dividing resistor for model discrimination The figure which shows the voltage-current characteristic of LED Flow chart showing lamp determination step

  Referring to FIG. 1, reference numeral 1 denotes a bathroom to which the LED lighting device according to the present invention is applied. This LED illumination device is composed of one power supply unit 2 and a plurality of lamps 31, 32, 33, 34.

  The power supply unit 2 is housed in the upper part of the ceiling 11 of the bathroom 1 and is usually configured not to be exposed to the outside. The power source 2 is supplied with AC power from an external commercial power source 21, and the lamps 31, 32, 33, and 34 are extinguished by a switch 22 provided on the dressing room side adjacent to the bathroom 1. It is configured as follows.

  Referring to FIG. 2, terminal portion 41, 42, 43, 44 is provided in power supply unit 2, and lamps 31, 32, 33, 34 are connected to terminal portions 41, 42, 43, 44, respectively. The In addition, the lamp connected to each terminal part 41, 42, 43, 44 is not restrict | limited, You may connect any lamp to any terminal part.

  These lamps 31, 32, 33, and 34 have different current values flowing through the internal LEDs, and therefore, different models. Therefore, resistors 311, 321, 331, and 341 having resistance values set in advance for each model are incorporated in the lamps 31, 32, 33, and 34. Then, when any lamp is connected to any terminal, the model of the lamp is read from the resistance value of the resistor built in the lamp, and constant current control is performed so that the current value corresponds to that model. Is configured to do.

  Referring to FIG. 3, power supply unit 2 includes a conversion unit 51 that converts AC power from an external commercial power source into DC power of a predetermined voltage, and a microcomputer unit 5 that controls the power supply unit 2. I have. Further, an illumination control unit 52 is connected to each of the terminal units 41, 42, 43, 44. The illumination control unit 52 adjusts the voltage of the DC power supplied from the conversion unit 51 and controls the current that flows to the lamp connected to each terminal unit. The voltage control and the current control are both performed by a signal from the microcomputer unit 5.

  When the switch 22 is turned on, the microcomputer unit 5 regulates the output voltage of each illumination control unit 52 to a voltage lower than any Vf of all types of lamps 31, 32, 33, 34 set in advance. . In this state, the lamp connected to any of the terminal portions 41, 42, 43, 44 does not emit light, but a current flows through the resistor 311 attached to the lamp 31, for example. Since the resistor 311 is configured to be connected in series to a resistor built in the illumination control unit 52, a partial pressure corresponding to the resistor 311 is generated in the illumination control unit 52. The microcomputer unit 5 reads the partial pressure, and the microcomputer unit 5 determines the model of the lamp 31 connected to the terminal unit 41.

  When the model of the lamp 31 is determined, the illumination control unit 52 performs constant current control so that the current preset for the lamp 31 is obtained. Further, when the lamp 22 is not connected to the terminal portion 42 at the time when the switch 22 is turned on, for example, the illumination control unit 52 connected to the terminal portion 42 is connected to all Vf as described above. Since a low voltage is output, even if the lamp 32 is connected to the terminal portion 42 in that state, no inrush current flows to the LED of the lamp 32, and the voltage applied when the lamp 32 is connected. Is immediately determined before the voltage Vf of the lamp 32 is exceeded, and preset constant current control for the lamp 32 is performed.

  By the way, in the state where constant current control is performed, the applied voltage exceeds Vf, so the gain of the signal input to the microcomputer unit 5 is high, but in the state where the model is discriminated, the applied voltage is higher than Vf. Since the voltage is low, the divided voltage is low, and thus the gain of the signal input to the microcomputer unit 5 is low.

  Therefore, as shown in FIG. 4, for example, the lamp 31 will be described. Two resistors 521 and 522 are provided as resistors to which the resistor 311 of the lamp 31 is connected in series. When performing constant current control, the transistor 524 is provided. Although the resistor 521 is short-circuited in the on state, the transistor 524 is turned off to increase the gain of the divided voltage input to the amplifier 523 when performing model discrimination. The output of the amplifier 523 is input to the microcomputer unit 5.

  In the present invention, voltage reset means is provided in the illumination control unit 52. This voltage reset means is composed of a resistor 525 and a transistor 526 connected in series. The transistor 526 is turned on / off by the microcomputer unit 5. Normally, the transistor 526 is off. However, when the lamp is determined by the microcomputer unit 5 when the lamp is discriminated, the voltage applied to the lamp 31 is short-circuited through the resistor 525 and the lamp 31 is turned on. Is once reset to zero. Transistor 526 is then immediately turned off.

  With reference to FIG. 5, this figure is a figure which shows the general voltage-current characteristic of LED. The current hardly flows until the voltage applied to both ends of the LED reaches Vf. However, when the voltage exceeds Vf, the current value increases rapidly, and the brightness of the LED increases almost in proportion to the current value. In the present invention, the threshold value Vt is set to a voltage lower than Vf.

  Referring to FIG. 6, when the lighting switch is turned on, the lamp type is determined. First, it is determined whether or not the voltage applied to the lamp is lower than Vt (S1). For example, when the on / off switch is turned on immediately after being turned off and the voltage applied to the lamp is higher than the threshold value Vt, the transistor 526 is turned on and discharge is started. (S2). When the voltage applied to both ends of the lamp is lowered to a voltage lower than the threshold value Vt, the transistor 526 is turned off to stop the discharge (S3), and then the above-mentioned lamp model determination is performed (S4).

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

DESCRIPTION OF SYMBOLS 1 Bathroom 2 Power supply part 5 Microcomputer part 21 Commercial power supply 22 Switch 31 Lamp 32 Lamp 33 Each lamp 34 Lamp 51 Conversion part 52 Lighting control part 311,321,331,341 Resistance 521,522,525 Resistance 523 Amplifier 524,526 Transistor

Claims (2)

  LED illuminating device comprising: a detachable lamp in which a plurality of LEDs are connected in series; and a power supply unit that supplies power to the lamp and emits the LED of the lamp when the lamp is detachably connected. The lamp has a plurality of types of lamps having different current values flowing through the LEDs, and a resistance having a resistance value set in advance for each type is parallel to the series circuit of the LEDs in each lamp. And when the lamp is not connected to the power supply unit, the voltage applied to the lamp connection unit is equal to or lower than a predetermined threshold value set to be equal to or lower than the forward voltage drop (Vf) of all types of lamps. When the lamp is connected to the voltage control unit that restricts the lamp, the voltage applied to the lamp is increased, and the type of the lamp is determined from the resistance value of the resistor provided to the lamp until the voltage exceeds the threshold and reaches Vf. Depending on the type of lamp connected If the voltage applied to the lamp exceeds the threshold value when starting the discrimination of the lamp, the voltage applied to the lamp is discharged. A voltage resetting means for forcibly returning the voltage to a state below the threshold once.   The constant current control and discrimination of the type of the lamp are performed by the partial pressure generated by connecting the resistance provided in the lamp and the resistance provided in the power supply section in series. The resistance value is switched so that the resistance value when determining the lamp is larger than the resistance value when performing constant current control, and the voltage dividing ratio when determining the type of lamp is increased. The LED lighting device according to claim 1.

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