JP2010033863A - Led bulb - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED bulb interchangeable with an incandescent lamp in a light emitting system for carrying out light control of luminance of an heat bulb by a light control controller. <P>SOLUTION: The LED bulb includes a bulb (32) provided with a mouthpiece attachable to a socket for an incandescent lamp, a base substrate (33) built in the bulb, rectifying circuits (14, 20) rectifying an alternating voltage input from the mouthpiece (31) and subjected to phase control or voltage control by the light control controller, smoothing circuits (15, 21) smoothing the rectified voltage, a switching circuit (16) having a function input with the smoothed voltage, outputting a voltage of a duty ratio responding to a set current, and adjusting a degree of the set current in response to the smoothed input voltage, and an LED circuit (17) built in the bulb, and emitting light of luminance corresponding to the alternating current input from the mouthpiece and subjected to the phase control or the voltage control by the light control controller by applying the output voltage and energizing the LEDs with the set current. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an LED bulb, for example, an LED bulb that is compatible with an incandescent bulb while maintaining a dimming function in a light-emitting system in which the luminance of a heat-generating bulb can be dimmed by a dimming controller.

  Conventional light emitting systems generally use a fluorescent lamp or an incandescent lamp as a light source. In such a light emitting system, a method of adjusting light by controlling the phase of the power supply voltage or controlling the voltage is employed.

  Recently, a high-intensity LED, for example, a high-intensity white LED has been put into practical use, and it has been put into practical use to employ an LED as a light source instead of a conventional fluorescent lamp or incandescent bulb (Patent Document 1). .

  In this type of LED lighting apparatus, a method of adjusting light by controlling a duty ratio of a pulsed applied voltage to the LED has been adopted (Patent Document 2).

JP 2007-145114 A JP 2005-524960 A

  However, since the conventional dimming circuit for incandescent bulbs is designed to perform dimming by controlling the phase or voltage of the power supply voltage, it cannot be dimmed if the existing heating bulb is replaced with an LED bulb as it is. This was an obstacle to the spread of LED bulbs.

  In view of such problems, the present invention provides an LED bulb that is compatible with an incandescent bulb while maintaining a dimming function in a light emitting system in which the luminance of the heat-generating bulb can be dimmed by a dimming controller. Let it be an issue.

  Therefore, the LED bulb according to the present invention is an LED bulb compatible with the incandescent bulb in the light emitting system capable of dimming the luminance of the incandescent bulb by phase control or voltage control of the power source by the dimming controller, A light bulb provided with a base that can be attached to the socket of the incandescent light bulb, a mounting board built in the light bulb, and a base board that is input from the base and phase-controlled or voltage-controlled by the dimming controller. A rectifier circuit that rectifies the alternating voltage, a smoothing circuit that is mounted on the base substrate and smoothes the rectified voltage, and that is mounted on the base substrate and receives the smoothed voltage as an input. A switch having a function of adjusting a magnitude of a set current according to the smoothed input voltage while outputting a voltage with a corresponding duty ratio And an AC voltage that is input from the base and phase-controlled or voltage-controlled by the dimming controller when the output voltage of the switching circuit is applied and a set current is applied to the LED. And an LED circuit that emits light with luminance corresponding to the above.

  One feature of the present invention is that a switching circuit having a function capable of arbitrarily changing the duty ratio of the output voltage according to the magnitude of the input voltage phase-controlled or voltage-controlled by the dimming controller is used. .

  As a result, it is possible to provide compatibility between the incandescent light bulb and the LED light bulb in the light emitting system in which the incandescent light bulb can be dimmed by the dimming controller without changing the light emitting system using the existing incandescent light bulb The incandescent bulb can be easily replaced with the LED bulb, and the luminance of the LED bulb can be dimmed by the existing dimming controller.

  The switching circuit can be configured to set the LED current according to the voltage across the variable resistor and adjust the voltage across the variable resistor according to the smoothed input voltage.

  Specifically, a second rectifier circuit that rectifies an AC voltage input from the base and phase-controlled or voltage-controlled by a dimming controller, a second smoothing circuit that smoothes the rectified voltage, and a smoothed signal. And a power supply voltage detector for detecting the magnitude of the input voltage, and the switching circuit can be configured to receive the output of the power supply voltage detector and adjust the voltage across the variable resistor.

  The switching circuit may be configured to receive the detected LED energization current as a feedback signal and to feedback control the duty ratio of the output so that the LED current becomes the set current.

  Hereinafter, the present invention will be described in detail based on specific examples shown in the drawings. 1 to 3 show a preferred embodiment of an LED bulb according to the present invention. In FIG. 1, an LED bulb 30 includes a base 31 at the rear end of a bulb 32, and a base substrate 33 and an LED unit 34 are built in the bulb 32, and a noise filter circuit 13 and a rectifier circuit 14 described later are included in the base substrate 33. , 20, smoothing circuits 15, 21, PWM switching circuit 16, power supply voltage detector 22 and current detector 18 are mounted, and LED unit 17, which will be described later, is mounted on LED unit 34.

  In FIG. 2, 10 is an AC commercial power source, 11 is a trimmer or thyristor, and is a dimming controller that performs phase control or voltage control of the power source voltage by adjusting the resistance value of the variable resistor, and 12 is an LED bulb 30. Input terminal (cap 31), 13 is a noise filter circuit for cutting noise from the input AC voltage of the input terminal 12, 14 is a rectifier circuit for rectifying the input AC voltage, and 15 is a smoothing circuit for smoothing the rectified voltage. is there.

  16 is a PWM switching circuit that receives the smoothed voltage as input, sets the energization current of the LED according to the magnitude of the voltage across the variable resistor 16A, and outputs a voltage with a duty ratio according to the set current; Are connected in series, and an LED circuit that emits an LED by applying an output voltage of the PWM switching circuit 16, 18 detects an energization current of the LED circuit 18, and outputs it to the PWM switching circuit 16 as a feedback signal Current detector.

  20 is a second rectifier circuit for rectifying the input AC voltage from the noise filter circuit 14, 21 is a second smoothing circuit for smoothing the rectified voltage, 22 is a variable resistor, and PWM is obtained from the smoothed voltage. The power supply voltage detector detects the magnitude of the input voltage of the switching circuit 16.

  The PWM switching circuit 16 adjusts the voltage across the variable resistor 16A according to the magnitude of the smoothed input voltage.

  The PWM switching circuit 16 receives the LED energization current detected by the current detector 18 as a feedback signal, and feedback-controls the output duty ratio so that the LED energization current becomes a set current.

  When the light control controller 11 is operated to perform phase control or voltage control of the power supply voltage 10, the controlled AC voltage is applied to the input terminal 12, noise is cut by the noise filter circuit 13, and rectified by the rectifier circuit 14. After being smoothed by the smoothing circuit 15, it is inputted to the PWM switching circuit 16.

  The PWM switching circuit 16 outputs to the LED circuit 17 a voltage with a duty ratio that becomes a current set by the variable resistor 16A, the LED of the LED circuit 17 emits light, and the LED energization current is detected by the current detector 18. The PWM switching circuit 16 outputs a feedback signal, and the PWM switching circuit 16 controls the duty ratio so that the LED energization current becomes the set current.

  On the other hand, the noise-cut voltage is rectified by the second rectifier circuit 20, smoothed by the second smoothing circuit 21, and then the magnitude of the smoothed voltage is detected by the power supply voltage detector 22, and PWM switching is performed. Input to the circuit 16.

  As shown in FIG. 3, the PWM switching circuit 16 variably controls the voltage across the variable resistor 16A in accordance with the level of the smoothed voltage so that the set current corresponds to the variably controlled voltage. Since the duty ratio of the output voltage is changed and controlled, the light emission luminance of the LED is dimmed.

It is a whole block diagram which shows preferable embodiment of the LED bulb which concerns on this invention. It is a figure which shows the circuit structure in the said embodiment. It is a figure which shows the relationship between the voltage and LED current in the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 AC commercial power supply 11 Dimming controller 14, 20 Rectifier circuit 15, 21 Smoothing circuit 16 PWM switching circuit 17 LED circuit 18 Current detector 22 Power supply voltage detector 30 LED light bulb 31 Base 32 Light bulb 33 Base substrate 34 LED unit

Claims (4)

An LED bulb compatible with the incandescent bulb in a light emitting system capable of dimming the brightness of an incandescent bulb by phase control or voltage control of a power source by a dimming controller,
A light bulb provided with a base that can be attached to the socket of the incandescent light bulb;
A mounting board built in the bulb;
A rectifier circuit mounted on the base substrate and rectifying an AC voltage input from the base and phase-controlled or voltage-controlled by the dimming controller;
A smoothing circuit mounted on the base substrate and smoothing the rectified voltage;
A function that is mounted on the base board and receives the smoothed voltage as an input, and outputs a voltage having a duty ratio according to the set current, while adjusting the magnitude of the set current according to the smoothed input voltage A switching circuit having
A luminance corresponding to an AC voltage input from the base and phase-controlled or voltage-controlled by the dimming controller when the output voltage of the switching circuit is applied and a set current is applied to the LED by being incorporated in the bulb. An LED circuit that emits light;
LED bulb characterized by comprising.   2. The switching circuit sets the LED current according to the voltage across the variable resistor, and adjusts the voltage across the variable resistor according to the level of the smoothed input voltage. LED bulb. A second rectifier circuit for rectifying an AC voltage input from the base and phase-controlled or voltage-controlled by the dimming controller; a second smoothing circuit for smoothing the rectified voltage; and the smoothed signal A power supply voltage detector for detecting the magnitude of the input voltage,
3. The LED bulb according to claim 2, wherein the switching circuit receives the output of the power supply voltage detector and adjusts the voltage across the variable resistor.   4. The switching circuit according to claim 1, wherein the switching circuit receives the detected LED energization current as a feedback signal, and feedback-controls the output duty ratio so that the LED current becomes a set current. The described LED bulb.

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