JP2006040669A - Light source lighting circuit and light emitting device having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device enabled to supply power with a proper range suitable for a light source like an LED, useful for reducing the size and weight of various kinds of light-emitting appliances like a light emission type push-button switch, a display light, an illumination apparatus, a photoelectric display, and a signal light, capable of coping with a wide-ranged input voltage like that of a free power source ranging from 80V to 279V, and maintaining long life. <P>SOLUTION: The light source lighting circuit for lighting one or a plurality of light sources comprises a rectifying circuit for rectifying an alternating current power source; and a supply voltage limiting circuit which supplies an output to the light source until the output voltage reaches a prescribed set value at rising of the output of the rectifying circuit, and supplies an output to the light source when the output voltage gets below a prescribed set value at falling of the output voltage of the rectifying circuit. The one or the plurality of light sources are pulse-lighted with small power consumption by cutting the supply of the output while the output voltage of the rectifying circuit is higher than the prescribed set value, and by cutting the wave form of high voltage area after rectification. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a light source lighting circuit for lighting one or a plurality of light sources composed of a light emitting diode (LED), an incandescent light bulb, and the like, and a light emitting device incorporating the light source lighting circuit. In the present invention, the light emitting device refers to, for example, a lighting type push button switch, a display light, a lighting type display device such as a warning light, a lighting fixture, an electric light display, a signal light, and other various types including an LED or an incandescent light bulb as a light source. Includes light-emitting devices.

Conventionally, as an illumination type push button switch and indicator lamp, an illumination type push button switch having a switch function and a display function for controlling on / off of driving of industrial equipment such as a machine tool and a control device, and a switch function. There are known LED lamps with only LED display function.
As a specific example of this type of display device, as shown in FIG. 7, for example, a push button 102 having a built-in LED 101 as a light source, and an input voltage from an AC power source (generally AC100V, 200V in general) by an on / off switching operation of the pushbutton 102. Etc.), an illuminated pushbutton switch comprising a drive on / off switching circuit 103 that supplies the industrial equipment, a light source lighting circuit that steps down the input voltage by the transformer 104 and supplies it to the LED 101, and the like. There is an indicator lamp that does not include the push button 102, the drive on / off switching circuit 103, and the like, but includes only an LED 101 as a light source and a light source lighting circuit that steps down the input voltage by the transformer 104 and supplies the LED 101 to the LED 101. is doing.

  Moreover, as a lighting fixture using a plurality of LEDs as light sources, for example, a bulb-type LED lighting device having a plurality of LEDs incorporated in a bulb as disclosed in Patent Literature 1, and Patent Literatures 2 and 3 are disclosed. There are also known stand-type lighting fixtures.

As described above, since the conventional lighting type display device uses a transformer, it is difficult to reduce the size and weight, and the input voltage is limited to 100V or 200V. In addition, since the LED 101 is lit with a minute current, there is a problem that the LED 101 malfunctions (erroneously lights) due to an induced voltage (minute current) or the like.
As a circuit for solving such a problem, there is known an AC driving circuit that does not use a transformer, as disclosed in Patent Document 4, for example.

In addition, lighting fixtures that use LEDs as light sources generally limit current with resistors, so there is a problem that the resistors that generate large currents generate much heat and power consumption increases. It was.
In order to solve such a problem, for example, some of the above-described light bulb type LED lighting fixtures are equipped with a capacitor voltage dividing type power supply circuit as shown in FIG.

JP 2004-134249 A JP 2000-98941 A JP 2004-103380 A JP 2002-153066 A

Since the conventional AC drive circuit described above has a circuit configuration that does not use a transformer, it can eliminate the problems caused by the above-described conventional transformer-type lighting circuit, but it is used for power storage for constantly supplying a constant current to the LED. Since the storage capacitor is a large capacitor, it is difficult to further reduce the size and weight of illuminated pushbutton switches, indicator lights, lighting fixtures, etc., and the life of the storage capacitor (generally 2000 There was a problem that the product life was determined in about 3000 hours). In addition, since the LED is always lit by supplying a constant current, there is a problem that the life of the LED is shortened.
Further, the capacitor voltage-dividing power supply circuit described above has a problem that it is not practical to increase the capacity of a high-voltage non-polar capacitor when it is desired to increase the current.

  The present invention has been made in view of such a conventional situation, and an object of the present invention is to appropriately supply power in an appropriate range to a light source such as an LED without using a transformer, a capacitor for electric storage, a voltage dividing capacitor, or the like. Small and lightweight lighting devices such as illuminated pushbutton switches and indicator lights, lighting equipment, light-emitting displays, signal lights, and other light-emitting devices equipped with LEDs and incandescent bulbs as light sources For light source lighting, which is extremely useful for manufacturing, can handle a wide range of input voltages such as 80 to 279 V free power supply, can maintain a long product life, and can greatly reduce power consumption An object is to provide a circuit and a light emitting device including the circuit.

  In order to achieve the above object, the first invention of the present application is a light source lighting circuit for lighting one or a plurality of light sources composed of a light emitting diode, an incandescent light bulb, etc., and a rectifier circuit for rectifying an AC power source; When the output of the rectifier circuit rises, the output voltage is supplied to the light source until the output voltage reaches a predetermined setting value set in advance. When the output of the rectifier circuit falls, the output voltage is set to the predetermined setting. A supply voltage limiting circuit for supplying an output to the light source when the value becomes lower than the value, the output supply is cut off while the output voltage of the rectifier circuit exceeds the predetermined set value, The waveform of the high portion is cut and the one or more light sources are pulse-lit.

  According to such a configuration, an appropriate range can be obtained while using a circuit that is compatible with a wide range of input voltages (for example, 80 V to 279 V free power source) without using a transformer or a capacitor for power storage. It is possible to turn on the light source by supplying the electric power in a timely manner. In addition to not using an expensive power storage capacitor for a short life, it is possible to extend the life of a light source such as an LED because of the pulse lighting system, and to provide a lighting circuit with a long service life at low cost. be able to. Further, since the waveform of the high voltage portion after rectification is cut, the power consumption of this portion is ignored, and the power consumption can be greatly reduced.

  The second invention of the present application is the first invention, further comprising a peak current limiting circuit for limiting a maximum value of the current supplied to the one or more light sources to be equal to or less than an allowable maximum current value of each light source. It is characterized by.

According to such a configuration, it is possible to limit the current supplied to the light source to be equal to or less than the allowable maximum current value of each light source, thereby preventing the possibility of damage to the light source due to the input of overcurrent.
In recent years, an LED having a large allowable maximum current value has been developed. When such an LED is used as a light source, a peak current limiting circuit is not necessarily required.

  The third invention of the present application is characterized in that, in the first invention or the second invention, when the voltage supplied to the one or more light sources is a minute value, the output supply to the light source from the supply voltage limiting circuit is cut off. A start voltage limiting circuit for preventing erroneous lighting of each light source is provided.

  According to such a configuration, it is possible to prevent a possibility that the light source malfunctions (incorrect lighting) due to an induced voltage (micro current) or the like.

In any one of the first to third inventions, when the AC power supply is at a high voltage (for example, 200 V), the second set value in which the output voltage is higher than the first set value when the output of the rectifier circuit rises. The supply voltage limit is set so that the output is supplied to the light source until the output reaches the output voltage and the output voltage to the light source is reduced when the output voltage of the rectifier circuit falls below the second set value. A high voltage input corresponding circuit for controlling the circuit may be provided, and the output supply may be cut off while the output voltage of the rectifier circuit exceeds the second set value, and the light source may be lit in pulses ( (See Japanese Patent Application No. 2003-15076 by the applicant). However, in this case, the input voltage is limited to the first set value (for example, 100 V) or the second set value (for example, 200 V).
Therefore, as in the fourth invention of the present application, when the input voltage from the AC power supply fluctuates, the predetermined set value in the output voltage of the rectifier circuit is continuously (substantially linear) according to the fluctuation of the input voltage. And a control circuit for changing the input voltage to be changed, and by changing the pulse width of the current value supplied to the one or more light sources by the control circuit for changing the input voltage, the supply current value ( It is preferable that the average value or the effective value be controlled to be substantially constant so that a wide range of input voltages can be handled.
The input voltage fluctuation control circuit changes the pulse width of the current value supplied to the one or more light sources so that the supply current value to each light source becomes substantially constant when the input voltage fluctuates, Are pulse-lit with a substantially constant brightness.
The change in pulse width accompanying the change in input voltage has a relationship as shown in FIG. That is, when the light source is an incandescent bulb, the pulse width needs to be changed as shown in FIG. 5 in order to obtain almost the same brightness even when the input voltage varies. For example, when the input voltage is 100 V, the pulse The predetermined set value is set by the input voltage fluctuation control circuit so that the pulse width is 2.6 mS when the width is 3.6 mS and the pulse width is 2.6 mS when the width is changed to 150 V and the pulse width is 2.1 mS when the width is changed to 200 V. Is continuously changed from the first set value V ₁ to the nth set value Vn, thereby making the supply current value (effective value) to the light source substantially constant and making the brightness of the light source substantially the same. be able to.
When the light source is an LED, the brightness is determined by the average current, so that the predetermined set value is set to the first set value V ₁ to the n-th set by the input voltage fluctuation corresponding control circuit as described above. By continuously changing to the value Vn, the supply current value (average value) to the light source can be made substantially constant, and the brightness of the light source can be made substantially the same.

  According to such a configuration, even if the input voltage fluctuates as in a free power source of, for example, 80V to 279V, the power in the proper range is supplied in a timely manner without greatly changing the supply ratio to the light source. Thus, the light source can be pulsed with a constant brightness.

The fifth invention of the present application includes variable means (for example, a variable resistor) for changing the predetermined set value in the output voltage of the rectifier circuit, and the current supplied to the one or more light sources by operation of the variable means. A dimming control circuit that controls the brightness of each light source by changing the pulse width is provided.
According to such a configuration, the brightness of each light source can be arbitrarily adjusted by operating the variable means.

The sixth invention of the present application is a light-emitting device incorporating at least one light source composed of a light-emitting diode, an incandescent light bulb, and the like and a light source lighting circuit for lighting the light source, wherein the light source lighting circuit is The light source lighting circuit according to any one of the first to fifth inventions.
Here, specific embodiments of the light emitting device include, for example, a lighting type push button switch, a lighting type display device such as an indicator lamp and a warning lamp, a lighting fixture, an electric display, and a signal lamp.

  The light-emitting device with such a configuration is equipped with a light source lighting circuit that eliminates the need for a transformer and a capacitor for storage, so it is significantly smaller and lighter than conventional light-emitting devices equipped with a transformer and a capacitor for storage. There are many advantages such as low cost, long life, and low power consumption.

(Claim 1)
Since the present invention is configured as described above, it is a small and lightweight circuit that does not use a transformer or a capacitor for electric storage, and can handle a wide range of input voltages such as a free power source of 80 V to 279 V, for example. However, it is possible to turn on the light source by supplying an appropriate range of power in a timely manner. In addition to not using an expensive power storage capacitor for its short life, the pulse lighting system extends the life of the light source and provides a low cost lighting circuit with a long service life and low power consumption. can do.

(Claim 2)
The current supplied to the light source can be limited to the allowable maximum current value of the light source to prevent the possibility of damage to the light source due to the input of overcurrent.

(Claim 3)
It is possible to prevent a possibility that the light source malfunctions (erroneously lights) due to an induced voltage (micro current) or the like.

(Claim 4)
Even if the AC power source is a wide-range power source such as a free power source that fluctuates in the range of 80V to 279V, for example, the power supply in an appropriate range is supplied in a timely manner without substantially changing the ratio of output supply to the light source. Can be pulsed at the same brightness.

(Claim 5)
Since the dimming control circuit is provided, the brightness of the light source can be arbitrarily adjusted by a variable resistor or other external components.

(Claims 6 and 7)
A light source lighting circuit that eliminates the need for transformers and power storage capacitors is installed, so that compared to conventional products, an illuminated pushbutton switch that can achieve a significant reduction in size and weight, cost reduction, longer life, and lower power consumption. There are many advantages such as providing a new light emitting device such as a lighting display device such as a display light or a warning light, a lighting fixture, an electric light display, and a signal light.

Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
FIG. 1A is a block diagram of a light source lighting circuit of the present embodiment, and FIG. 2 is a circuit configuration diagram as a more detailed example of the light source lighting circuit.
As shown in FIG. 1A, the light source lighting circuit includes a rectifier circuit 4, a supply voltage limiting circuit 5, a light source (one or a plurality of LEDs (light emitting diodes) or an incandescent light bulb) 6, a peak current limiting circuit 7, A starting voltage limiting circuit 8, an input voltage fluctuation control circuit 9, a dimming control circuit 10 and the like are provided.

The rectifier circuit 4 is a circuit for rectifying the AC power supply 3.
The supply voltage limiting circuit 5 supplies an output to the light source 6 until the output voltage reaches a predetermined setting value (V _{1 to} Vn described later) when the output of the rectifying circuit 4 rises. This is a circuit for supplying output to the light source 6 when the output voltage falls below the predetermined set value at the fall of the output.
The peak current limiting circuit 7 is a circuit that limits the maximum value of the current supplied to the light source 6 to be equal to or less than the allowable maximum current value I _lim of the light source 6.
The starting voltage limiting circuit 8 cuts off the supply of output from the supply voltage limiting circuit 5 to the light source 6 when the AC power supply 3 is at a low voltage (when it does not reach a starting minimum voltage value V _0-1 described later). In this way, the light source 6 is prevented from being erroneously turned on.
The light source 6 is, for example, a light source that illuminates a push button switch or the like, a light source of a lighting fixture or an electric display, and the like. FIG. 1B shows a case where the light source 6 is a plurality of LEDs, FIG. 1C shows a case where it is a single LED, and FIG. 1D shows a case where it is a single incandescent bulb.
When the input voltage from the AC power supply 3 fluctuates, the input voltage fluctuation corresponding control circuit 9 adjusts the predetermined set value at the output of the rectifier circuit 4 to the first set value V ₁ according to the fluctuation of the AC power supply 3. To the nth set value Vn, the pulse width of the current value supplied to the light source 6 is changed, and the supply current value (average value or effective value) to the light source 6 is substantially constant. 6 is a circuit for controlling the supply voltage limiting circuit 5 so as to supply the output to 6.

  The details of the configuration of the light source lighting circuit of the present embodiment will be described below with reference to FIG.

This light source lighting circuit is connected via a pair of connection terminals 1 and 2 to an AC power source 3 as a free power source whose power source voltage varies between 80V and 279V. Note that the value of the power supply voltage is not limited to this.
The rectifier circuit 4 is a bridge circuit.

  The supply voltage limiting circuits 5a and 5b indicate that a voltage (predetermined set value) set in advance by the voltage dividing ratio of the resistors R2 and R4 and the Zener diode ZD7 has reached a voltage dividing point between the resistors R2 and R4. The switching transistor Q3 is turned on / off by detection at a, and the transistor Q5 serving as a main switch is turned off at the predetermined set value or more, whereby the output voltage V of the rectifier circuit 4 is set to the predetermined value. While the set value is exceeded, the output supply is cut off and the light source 6 is pulsed (pulse driven). The predetermined set value can be arbitrarily set in advance by a combination of resistors R2 and R4 and a Zener diode ZD7.

The peak current limiting circuit 7 is a constant current circuit including a diode D4, a resistor R9, a Zener diode ZD5, and a transistor Q4. The peak current limiting circuit 7 is provided for the purpose of limiting the peak current of pulse driving of the light source 6, and the current flowing through the resistor R9 When the maximum allowable current value I _lim is exceeded (for example, 60 to 100 mA), the voltage across the resistor R9 (voltage drop) is compared with the Zener voltage of the Zener diode ZD5 to control the transistor Q4, thereby The transistor Q5, which is the main switch, is controlled to limit the maximum value of the current supplied to the light source 6 to the allowable maximum current value I _lim or less.

The start-up voltage limiting circuits 8a and 8b include a resistor R13, a resistor R8, a Zener diode ZD8, a charging capacitor C2, a resistor R1, an FET Q6, a resistor R10, and a switching transistor Q1, and the voltage dividing ratio of the resistors R13 and R8 and the Zener diode ZD8 An arbitrarily set voltage (starting minimum voltage value V _0-1 ) is detected at a voltage dividing point b between the resistors R13 and R8 to turn on / off the FET Q6, and light sources from the supply voltage limiting circuits 5a and 5b 6 is configured to limit the supply of power to 6. That is, when the AC power supply 3 is at a low voltage and the voltage dividing point b is less than the starting minimum voltage value V _0-1 , the FET Q6 is turned off, whereby the transistor Q1 is turned on and the transistor Q5 is turned off. While the output supply to the light source 6 from the voltage limiting circuits 5a and 5b is cut off, the FET Q6 is turned on when the voltage of the AC power supply 3 is increased and the voltage dividing point b detects the starting minimum voltage value V _0-1 or more. As a result, the transistor Q1 is turned off and the transistor Q5 is turned on, so that the output supply from the supply voltage limiting circuits 5a and 5b to the light source 6 is made normal.
The capacitor C2 is for stabilizing the voltage (voltage at the voltage dividing point b) based on the voltage dividing ratio of the resistors R13 and R8 and the Zener diode ZD8.

The input voltage fluctuation response control circuit 9 is a circuit that enables a response to a wide range of input voltages (for example, 80 V to 279 V).
That is, the brightness of the light source 6 changes when the predetermined set value described above is constant for each input voltage. For example, when the light source 6 is an incandescent light bulb, the pulse width must be changed as shown in FIG. 5 in order to make the light source 6 have almost the same brightness even when the input voltage varies. Therefore, when the light source 6 is driven, an input voltage that continuously varies the predetermined set value from the first set value V ₁ to the n-th set value Vn so as to be controlled to such a pulse width. Fluctuation control circuit is provided.
When the light source 6 is an LED, the brightness is determined by the average current. Similarly to the above, by providing an input voltage fluctuation corresponding control circuit that changes the predetermined set value so that the average current becomes substantially constant, the supply current value to the light source 6 can be made substantially constant with respect to the input voltage fluctuation. And the brightness can be almost the same.

The control circuit 9 corresponding to the input voltage fluctuation in the illustrated example includes circuits 9-1 to 9-n (intermediate circuits) including a resistor R12, a resistor R15, a Zener diode ZD6, a charging capacitor C1, a resistor R15, a resistor R5, an FET Q2, and a resistor R16. The circuits 9-2, 9-3,... Are not shown), and each of the circuits 9-1 to 9-n is arbitrarily set according to the voltage dividing ratio of the resistors R12 and R15 and the Zener diode ZD6. A circuit in which (breaking voltage change voltage value V _0-2 ) is detected at a voltage dividing point c between resistors R12 and R15 to turn on / off FET Q2, and resistor R16 is connected in parallel to resistor R4 by turning on FET Q2. The threshold voltage (predetermined predetermined set value) at the voltage dividing point a is changed from the _first set value V ₁ to the second set value V ₂ so as to be configured. Action Thus, when the output of the rectifier circuit 4 rises, the output voltage is supplied to the light source 6 until the output voltage reaches the second set value V ₂ higher than the first set value V _1, and the output of the rectifier circuit 4 falls. sometimes the output voltage controls the second set value V output supply supply voltage limiting circuit 5a to perform the _two to the light source 6 when it is below, 5b, i.e., the cut-off voltage of the output supply to the light source 6, It is adapted to change from the first set value V ₁ to the second set value V _2. The second set value _{V 2} includes resistors R2, R4, R16, can be arbitrarily set by the combination of the Zener diode ZD7.
Therefore, the arbitrarily settable predetermined set values V ₁ , V ₂ , V ₃ , V ₄ ,..., Vn are appropriately set in the respective circuits 9-1 to 9-n (for example, in FIG. as shown, for each point of the pulse width of the incandescent bulb, provided at appropriate settings _V 1 to Vn in the circuit 9-1 to 9-n of each) by, the input voltage change of 80V~279V On the other hand, the pulse width is continuously changed, and the light source 6 can be maintained at substantially the same brightness.
The capacitor C1 is for stabilizing the voltage (voltage at the voltage dividing point c) based on the voltage dividing ratio of the resistors R12 and R15 and the Zener diode ZD6.

  The dimming control circuit 10 uses the resistor R4 in the drawing as a variable resistor, for example, so that the voltage at the point a changes, so that the predetermined set value changes and the brightness of the light source 6 is arbitrarily adjusted. Can do.

Next, the operation of the light source lighting circuit will be described with reference to FIGS. FIG. 3 shows a relationship between the voltage V of the full-wave rectification, the first set value V ₁ , the allowable maximum current value I _lim , and the time t when the voltage of the AC power supply 3 is 100V.

  The output subjected to full-wave rectification by the rectifier circuit 4 is supplied to the light source 6 through the supply voltage limiting circuits 5a and 5b.

A divided voltage for determining that the supplied voltage V is a minute current such as an induced voltage and the dividing point b is lower than the minimum activation voltage value V _0-1 (for example, less than 70 V). When it is a value, it is less than the threshold voltage of the FET Q6, so that the FET Q6 is turned off. As a result, the switching transistor Q1 is turned on, the transistor Q5 of the main switch is turned off, and the output supply to the light source 6 is cut off.

When the voltage V output by the rectifier circuit 4 rises and reaches the divided voltage value at which the voltage dividing point b exceeds the starting minimum voltage value V _0-1 , the voltage exceeds the threshold voltage of the FET Q6, and the FET Q6 is turned on. Become. As a result, the switching transistor Q1 is turned off, the transistor Q5 is turned on, and the output supply to the light source 6 is performed.
Voltage V output by the rectifier circuit 4, while lower than the first set value V ₁ shown in FIG. 3 (A), the output supply to the light source 6 is continued.
At this time, when the peak current limiting circuit 7 is provided, the light source 6 can be supplied with a current that does not exceed the allowable maximum current value I _lim as shown in FIG.

Voltage V output by the rectifier circuit 4, the first exceeds the set value V _1, the switching transistor Q3 is turned on. Thereby, the transistor Q5 is turned off, and the output supply to the light source 6 is cut off.

Voltage V output by the rectifier circuit 4 becomes lower than the first set value V _1, the switching transistor Q3 is turned off, the transistor Q5 is turned on, the output supply to the light source 6 is performed.
In this way, the output supply to the light source 6 is intermittently performed, so that the light source 6 is pulsed as shown in FIGS. 3 (C) and 3 (D). In FIG. 3C, since the current that does not exceed the allowable maximum current value I _lim is supplied to the light source 6, there is no possibility that the light source 6 is damaged by the input of overcurrent.

FIG. 4 shows a case where the voltage of the AC power supply 3 fluctuates to a high voltage (for example, 200 V). When the full-wave rectified voltage V, the first set value V ₁ , and the voltage of the AC power supply 3 change to a high voltage, The relationship between the second set value V ₂ , the allowable maximum current value I _lim , and the time t is shown.

Input voltage change corresponding control circuit 9, the voltage of the AC power source 3 is, for example, when one which was at 100V initially fluctuates to 120V and 200V, the second when the change first set value V ₁ to a high voltage by the direction of the set value V ₂ can be continuously varied, it can be substantially constant the current supplied to the light source 6.

At this time, when the peak current limiting circuit 7 is provided, a current that does not exceed the allowable maximum current value I _lim as shown in FIG.

In this way, the output supply to the light source 6 is intermittently performed, so that the light source 6 is pulsed as shown in FIGS. 4C and 4D. In FIG. 4C, since the current that does not exceed the allowable maximum current value I _lim is supplied to the light source 6, there is no possibility that the light source 6 is damaged by the input of overcurrent.
Further, the operation of the input voltage fluctuation control circuit 9 does not substantially change the ratio of the output supply to the light source 6, and supplies power in an appropriate range in a timely manner as in the case where the AC power supply is 100V. 6 can be brightly pulsed.
Furthermore, if necessary, by providing the dimming control circuit 10, the brightness can be arbitrarily adjusted by changing the pulse width of the current supplied to the light source 6 by an external component (variable resistor R4) or the like.

FIG. 6 shows an illuminated pushbutton switch as an example of an embodiment of a lighting type display device according to the present invention.
This illuminated pushbutton switch includes a pushbutton 102 having a built-in LED 101 as a light source, and an input voltage (generally AC100V, 200V, etc.) from an AC power source to an unillustrated industrial device or the like by an on / off switching operation of the pushbutton 102. A drive on / off switching circuit 103 to be supplied and a light source lighting circuit 110 for supplying the input voltage to the LED 101 are provided. The light source lighting circuit 110 is the above-described light source lighting circuit shown in FIG. The circuit configuration is small and light and does not include a transformer or a storage capacitor, and is built in the casing of the drive on / off switching circuit 103.
The illuminated pushbutton switch of this example having such a configuration is greatly reduced in size and weight and cost compared with the conventional illuminated pushbutton switch mounted with a transformer (see FIG. 7) and storage capacitor mounted. It is possible to extend the life.
Further, the light source lighting circuit 110 can be integrated with the above-described light source lighting circuit configuration shown in FIG. 1, and in that case, the light source lighting circuit 110 can be built in the holding case 102a of the push button 102, or Can be miniaturized until it is built in the LED 101.
The lighting type display device according to the present invention is not limited to the illumination type push button switch, and does not include the switch function unit such as the push button 102 and the drive on / off switching circuit 103 but includes only the display function by the light source 101. It is also possible to implement the display lamp in which the circuit for lighting the light source is the light source lighting circuit 110.

  Further, as an example of a lighting fixture, the light source lighting circuit of this example is incorporated into the above-described known bulb-type LED lighting fixture, stand-type lighting fixture, etc., so that the LED lighting with low power consumption and a wide range of input voltages is possible. It can also be provided as an instrument.

  The embodiments of the light source lighting circuit according to the present invention and the light emitting device including the light source lighting circuit have been described above with reference to the drawings. However, the present invention is not limited to these embodiments, and It goes without saying that various modifications can be made within the technical scope described in each claim.

The block diagram which shows an example of embodiment of the circuit for light source lighting which concerns on this invention. The circuit diagram which shows an example of the circuit structure of the circuit for light source lighting shown in FIG. The principal part waveform figure at the time of 100V input in embodiment of FIG. FIG. 3 is a main portion waveform diagram at the time of high voltage input in the embodiment of FIG. 2. The graph which shows the relationship between pulse width and input voltage when a light source is an incandescent lamp. The perspective view which shows an example of embodiment of the illumination type pushbutton switch as a lighting type display apparatus which concerns on this invention. The perspective view which shows an example of the illumination type pushbutton switch as the conventional lighting type display apparatus. The circuit diagram of the capacitor | condenser partial pressure type used for the conventional LED lighting fixture.

Explanation of symbols

3: AC power supply 4: Rectifier circuit 5, 5a, 5b: Supply voltage limiting circuit 6: Light source (one or more LEDs, incandescent light bulb)
7: Peak current limiting circuit 8, 8a, 8b: Start-up voltage limiting circuit 9: Input voltage fluctuation control circuit 10: Dimming control circuit

Claims (7)

A light source lighting circuit for lighting one or a plurality of light sources composed of a light emitting diode, an incandescent light bulb, etc.
A rectifier circuit for rectifying an AC power supply;
When the output of the rectifier circuit rises, the output voltage is supplied to the light source until the output voltage reaches a predetermined set value set in advance, and when the output of the rectifier circuit falls, the output voltage becomes the predetermined set value Provided with a supply voltage limiting circuit for supplying power to the light source when
While the output voltage of the rectifier circuit exceeds the predetermined set value, the output supply is cut off, and the waveform of the high voltage portion after rectification is cut so that the one or more light sources have low power consumption. A light source lighting circuit, characterized in that it is configured to perform pulse lighting.   2. The light source lighting circuit according to claim 1, further comprising a peak current limiting circuit that limits a maximum value of a current supplied to the one or more light sources to an allowable maximum current value of each of the light sources. .   A startup voltage limiting circuit that blocks output supply to each light source from the supply voltage limiting circuit to prevent erroneous lighting of each light source when a voltage supplied to the one or more light sources is a minute value; 3. The light source lighting circuit according to claim 1, further comprising a light source lighting circuit.   An input voltage fluctuation corresponding control circuit that continuously changes the predetermined set value in the output voltage of the rectifier circuit according to the fluctuation of the input voltage when the input voltage from the AC power supply fluctuates; The input voltage fluctuation control circuit can control the supply current value to each light source by changing the pulse width of the current value supplied to the light source or light sources, and can handle a wide range of input voltages. The light source lighting circuit according to any one of claims 1 to 3, wherein:   Variable means for changing the predetermined set value in the output voltage of the rectifier circuit, and by operating the variable means, the pulse width of the current supplied to the one or more light sources is changed to change the brightness of each light source. The light source lighting circuit according to claim 1, further comprising a dimming control circuit for adjustment.   A light-emitting device incorporating at least one or a plurality of light sources such as light-emitting diodes or incandescent bulbs and a light source lighting circuit for lighting the light sources, wherein the light source lighting circuit is defined in claims 1 to 5. A light emitting device comprising the light source lighting circuit according to any one of the preceding claims.   The light-emitting device according to claim 6, wherein the light-emitting device constitutes any one of a lighting-type display device such as an illuminated pushbutton switch, a display lamp or a warning lamp, a lighting fixture, an electric display, and a signal lamp.

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