JPH09326299A - Light source driving system and fluctuation signal generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To artificially obtain the emitting light such as a candle light in an electric light source by using a thing to change a noise generated according to a temperature change as a noise generating source, and arranging the noise generating source so as to receive influence of wind from an external part. SOLUTION: A light source driving system is provided with a noise generating source to generate a random noise and a driving circuit 5 to drive a light source 6 on the basis of an output signal of the noise generating source. A thing to change a noise generated according to a temperature change is used as the noise generating source 1, and the noise generating source is arranged so as to receive influence of wind from an external part. In order that the noise generating source receives influence of wind from an external part, for example, a hole is arranged in a casing to house the light source driving system, and the noise generating source is arranged so as to receive wind from this hole, or a part of the noise generating source is arranged so as to come outside the casing.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an incandescent lamp and an LED.
The present invention relates to a light source driving device that simulates a natural bright and dark pattern of a candle that emits light such as a light source, and a fluctuation signal generating device for realizing such driving.

[0002]

2. Description of the Related Art It has been practiced to simulate the flame of a candle by using an electric lighting device such as an incandescent light bulb or an LED so that the same lighting feeling as when using a candle can be obtained. For example, in Japanese Patent Laid-Open No. 6-52709, a light bulb imitating the shape of a candle flame is used, and a light bulb unit is attached to a metal piece arranged close to an electromagnet connected to an oscillator and mechanically vibrated. Discloses a method of turning on / off light emission irregularly. However, with this method, the light bulb only mechanically oscillates, and even if the signal from the commercial power supply or the oscillator is changed to generate irregularity, the brightness of the light emission does not change, and the light emission of the candle is changed. Unnaturalness remains compared with it. There is also a method of vibrating the filament of the light bulb according to the light emission, but each of them has unnatural light emission, which is different from the pattern of light and dark emitted by the candle.

On the other hand, Japanese Patent Application Laid-Open No. 2-44693 discloses a method of changing the illuminance of a lighting fixture in accordance with so-called 1 / f fluctuation in order to obtain more comfortable lighting for humans. The method disclosed here is a method for obtaining more comfortable lighting for humans, and is not a method for simulating the flame of a candle with an incandescent light bulb, so that the same lighting feeling as using a candle can be obtained. I can't. Also,
Japanese Patent Laid-Open No. 2-44693 discloses a method of generating a fluctuation signal by using a minute voltage fluctuation at both ends of a resistor, or a ROM storing a numerical sequence having 1 / f fluctuation in advance. A method of reading it and generating a fluctuation signal is disclosed.

Further, Japanese Patent Laid-Open No. 7-14680 is intended to improve the fact that the lighting according to 1 / f fluctuation does not occur due to the time delay from the on / off time to the actual light emission / extinction like an incandescent light bulb. , A device that divides a drive signal, delays each signal separately, and then synthesizes and emits light. However, since this device is not a device that imitates the flame of a candle with an incandescent lamp, it is not possible to obtain the same lighting feeling as when using a candle.

[0005]

As described above, as described above,
There is no method or device in the above-mentioned known example for simulating a candle with an electric light source such as an incandescent lamp or an LED. Therefore, no reference is made to the light emission state peculiar to the candle that sways according to the wind, and there is no disclosure about a light source driving device and a driving method for realizing such a light emission state.

In order to realize a candle-like light emission state by simulating a candle with an electric light source, it is necessary to simulate a natural light emission state of the candle, which is likely to disappear when the wind blows, or conversely becomes brighter. However, it was not possible to imitate such a light emitting state peculiar to a candle flame.

The present invention is a light source driving device for simulating a candle flame with an electric light source and artificially obtaining light emission as if the electric light source was a candle, and a fluctuation signal generating device therefor. The purpose is to realize.

[0008]

FIG. 1 is a diagram showing a basic configuration of a light source driving device according to a first aspect of the present invention. In order to achieve the above object, the light source driving device of the present invention includes, as shown in FIG.
In the light source drive device including the drive circuit 5 that drives the light source 6 based on the output signal of the noise source, the noise source 1
The feature is that a noise generator that changes the noise generated according to temperature changes is used and the noise source is placed so as to be affected by the wind from the outside.

In order to prevent the noise source from being affected by the wind from the outside, for example, a hole is provided in the housing for accommodating the light source driving device, and the noise source is arranged so as to receive the wind from the hole. Make sure that part of the noise source is outside the housing.

When the light source is pulse-driven and the pulse width is changed to simulate a candle, the light source periodically changes at a frequency higher than the frequency range of the signal output by the noise source 1, and the noise source 1 A comparison circuit that compares a predetermined reference signal having an amplitude larger than the change range of the output signal and generates a pulse signal based on the comparison result is provided, and the light source is driven based on the pulse signal.

For example, a Zener diode or a thermistor is used as a noise generation source for changing noise generated according to a temperature change, and a voltage generated when a current is passed through them is amplified to be a noise signal. It is desirable to be able to change the fluctuation state by making the voltage amplification variable.

Of the signals generated by the noise source,
It is desirable to remove signals below a predetermined frequency and above a predetermined frequency, for example, signals outside the frequency range of 0.1 Hz to 10 Hz.

Further, the fluctuation signal generator of the present invention generates a fluctuation signal of 1 / f when the frequency is f.
Of the signals generated by the / f fluctuation signal generation source and the 1 / f fluctuation signal generation source, signals with a frequency lower than or equal to a predetermined frequency and higher than a predetermined frequency are signals other than those in the frequency range of 0.1 Hz to 10 Hz, for example. And a filter circuit for removing.

When a current is passed through a resistor, a Zener diode, a thermistor, etc., the voltage generated at the end of the resistor changes minutely and randomly. In Japanese Patent Laid-Open No. 2-44693, the noise causes the frequency to change. It is disclosed that when it is f, it has a 1 / f spectrum. Therefore, it is possible to generate a random noise signal having a 1 / f spectrum by amplifying this noise with a large gain. Further, it is known that when a current is passed through a resistor, a Zener diode, a thermistor, etc., the voltage generated at the end of the resistor changes according to the temperature change. Therefore, if the wind that hits the surface changes and the temperature changes slightly,
The noise changes greatly. Therefore, when noise generated at the ends of resistors, Zener diodes, thermistors, etc. is amplified to generate a fluctuation signal and the fluctuation signal is used to drive the light source, noise sources such as resistors, Zener diodes, thermistors, etc. are used to influence the wind. By arranging so that the temperature changes, it is possible to simulate how the wind blows.

The Zener diode or thermistor is suitable for such a purpose because the generated voltage has a larger rate of change in accordance with the temperature change than the resistance or the like. For example, the change rate of a 9V Zener diode is several meters.
The voltage is about V / ° C., and the characteristics are positive and negative depending on the Zener voltage. Therefore, when the Zener voltage is amplified, a fluctuation signal similar to 1 / f is generated, but a component that greatly changes when the temperature changes is added. If a Zener diode is placed at a position affected by wind or the like, and if the temperature changes minutely due to the influence of wind or the like but changes instantaneously, the fluctuation of the Zener voltage also increases accordingly. Therefore, the fluctuation of the Zener voltage increases in accordance with the wind, etc., and a light emission state as if the candle fluctuates in the wind can be realized. The fluctuations are the same even if the positive and negative characteristics are reversed as described above.

When changing the light emitting state of the light source, it is easier to drive with a pulse signal and change the pulse width than changing the drive current or drive voltage.
Therefore, it is conceivable to generate a signal (PWM signal) whose pulse width changes according to the noise signal output from the noise generation source. If the temperature of the noise source changes slowly, the level of the noise signal will change. Therefore, if a pulse signal is generated simply by comparing noise with a constant level signal, a very bright lighting state and a very dark almost extinguished state may continue for a long time.
Such a state is not preferable for simulating a candle. In particular, if the light is almost off for a long time, the user may think that a failure has occurred. Therefore, a pulse signal is generated by periodically changing at a frequency higher than the frequency range of the signal output by the noise generation source and comparing with a predetermined reference signal having an amplitude larger than the change range of the signal output by the noise generation source. By doing so, although there is a large change when the wind is blown, it is possible to turn on the light in a state where the fluctuation is not so large normally.

Further, as described above, when the temperature changes and the temperature of the entire atmosphere around the apparatus changes, the level of the Zener voltage changes greatly, so it is desirable to remove the DC component. Furthermore, changes that are faster than a certain degree are not very recognizable to humans and are not only unnecessary for simulating a candle, but it is better to remove their frequency components.
Also, low frequency components produce slow changes, which are not only necessary for humans to recognize such changes, but are not necessary to simulate a candle flame.
Since the average level of the fluctuation signal fluctuates, there arises a problem that the brightness level changes greatly. Therefore, it is desirable to remove frequency components below a certain level, for example, frequency components below 0.1 Hz. This applies not only to driving a light source for illumination but also to a fluctuation signal for giving a natural feeling to humans.

[0018]

FIG. 2 is a diagram showing the basic configuration of an embodiment of a lighting device using the light source driving device of the present invention,
FIG. 3 is a diagram for explaining the principle of pulse signal generation in the comparison circuit.

The lighting device of FIG. 2 controls the current flowing through the lamp 6 of the incandescent light bulb by turning on / off the switch of the FET 5, and the lamp is changed by changing the ratio of the time when the FET 5 is turned on (duty ratio). The brightness of 6 changes. The noise source 1 generates a minute noise signal of μV to mV. The bandpass filter / gain control amplifier 2 has an amplification function of amplifying a minute noise signal generated by the noise generation source 1 with a high gain, and allows only a signal in a predetermined frequency range to pass through, and attenuates a signal outside this frequency range. It has a band pass filter function. The gain of amplification is adjustable. The reference signal generation circuit 3 periodically changes at a frequency higher than the frequency range of the signal output by the bandpass filter / gain control amplifier 2 and has an amplitude larger than the change range of the signal output by the bandpass filter / gain control amplifier 2. Generate the reference signal of. A sawtooth signal or a triangular wave signal is desirable as the reference signal,
A signal such as a sinusoidal signal may be used. The comparator 4 is
The noise output from the bandpass filter / gain control amplifier 2 is compared with the reference signal output from the reference signal generation circuit 3 to generate a pulse signal. Generation of a pulse signal will be described with reference to FIG.

As shown in FIG. 3, a bandpass filter
The noise as shown in the figure is output from the gain control amplifier 2, and a triangular wave is output as a reference signal. Reference signal is bandpass filter / gain control amplifier 2
Is a signal that periodically changes at a frequency higher than the frequency range of the noise signal that is output by and has a larger amplitude than the noise signal change range. The average level of the noise signal output by the bandpass filter / gain control amplifier 2 is set to the intermediate level of the triangular wave. for that reason,
A signal as shown in the figure is input to the comparator 4. The comparator 4 compares the two input signals and generates a pulse which becomes "high" when the reference signal is larger than the noise signal and "low" when the reference signal is small. Since the noise signal changes at random, the pulse width of the generated pulse signal changes and the brightness of the lamp 6 also changes.

FIG. 4 is a diagram showing a circuit configuration of the light source driving device of the first embodiment of the present invention. The light source drive device of the first embodiment is an example in which an incandescent light bulb is used as a light source and a commercial power source such as AC100V is used as a power source.

In order to generate a sawtooth wave which is a triangular wave,
Since the peak voltage of C is as high as 141V, a low voltage waveform f of about 14 to 15V is obtained by connecting the resistors 7 and 8 in series in order to obtain an input voltage that can be used in a normal operational amplifier.
It is connected to the negative input of the comparator 11. On the other hand, resistors 9 and 10 are used for the positive input of the comparator 11 to obtain the threshold voltage. For example, the peak of negative input is 13V
If it is set to a degree, the positive input is set to DC2.5V. As a result, the output of the comparator 11 produces a thin rectangular waveform g. Further, in order to make this a sawtooth wave, the diode 1
2 and the capacitor 14 can generate the sawtooth waveform shown in the waveform h. A capacitor 13 connected in parallel with the diode 12 is used to speed up the rising of the sawtooth wave. On the other hand, noise is generated and generated by the Zener diode 1
5 is connected as a positive input to the operational amplifier 16 through resistors 18 and 19 for obtaining a Zener drive current. The operational amplifier 16 is a high gain amplifier having a bandpass filter function, and amplifies only a minute AC noise component of the Zener diode which is a noise generation source. The gain is given by the ratio of the resistance 22 and the resistance 21
If 1 and R2, then G = 1 + (R2 / R1). Furthermore, the capacitor 23 is a resistor 2 as a low-pass filter.
Since it is connected and installed in series with 2, it works as a high-pass filter.

For example, if the cut frequency is 0.1 HZ, R1 = 15 KΩ, and if R2 = 2.2 MΩ is used, C = 22.
It is about μF and has an attenuation characteristic of 12 dB. On the other hand, by connecting the capacitor 20 in parallel with the R2 of the resistor 21, a low-pass filter function is obtained, and when it is set near the cut frequency of 10 HZ, it becomes about 0.22 μF. In this example, the gain is about 150 times using the above equation. Further, in order to increase the amplification degree and to make the filter characteristic steep, the amplifier of the operational amplifier 17 is connected, and the feedback resistor R2 and the variable resistor 26 are prepared so that the gain can be adjusted. To make the characteristics of the high-pass filter steep, double the capacitor 25 to 4
It is effective to use 7 μF. The attenuation characteristic of the filter is 18 dB due to the two-stage amplifier, which is an effective means for producing the flaming of a candle. The resistors 19 and 24 connected to the input of the operational amplifier operate. The noise generation voltage has an amplification degree of about 40 dB in the two-stage amplifier and becomes a comparison level with the sawtooth wave. In this example, assuming that the operational amplifier is operated at 15V, the peak voltage of the sawtooth wave is about 15V, and the frequency is 100 or 120HZ, which is twice the frequency of the AC commercial power supply. The noise voltage is centered around 9 to 10 V, and the noise signal fluctuates between 0 V and 15 V. Therefore, as described in FIG. 1, the sawtooth wave signal and the noise signal are connected to the operational amplifier 4 to obtain a binary output signal whose pulse width changes according to the level of the noise signal, which is connected to the gate of the FET 5 Turn on and off. Also, the resistor 2 in the figure
7, the Zener diode 28, and the capacitor 29 are constant voltage power supplies for obtaining the power supply of the operational amplifier.

As described above, in the light source drive device of the first embodiment, the pulse width of the pulse signal for lighting the lamp 6 changes randomly, so that the lighting state fluctuates and a sensation similar to a candle is given. In particular, if the area around the lamp 6 is surrounded by translucent glass or the like, a feeling closer to a candle is given. Further, the Zener diode 15 is sensitive to temperature changes, and even if it is minute, a large temperature change causes a large fluctuation. By utilizing this, the structure for obtaining the feeling of fluctuating in the wind will be explained.

FIG. 5 is a diagram showing an external appearance and an internal state of a lighting device using the light source driving device of the first embodiment. FIG.
As shown in (1), the lighting device has a shape simulating a candle, and the lamp 6 is attached to the white housing 50. The circuit of the light source driving device shown in FIG.
To be housed. Further, the housing 50 is provided with a hole 51 so that external wind is blown into the inside of the housing 50. As shown in (2) of FIG. 5, the printed circuit board 52 on which the circuit of the light source driving device shown in FIG. 4 is formed is attached to the housing 50, and the zener diode 1
5 is arranged so as to be located near a hole 51 provided in the housing 50, and when external wind blows through this hole 51, it hits the surface of the Zener diode 15 and changes its temperature, albeit a minute amount. It is like this. Therefore, when the illuminating device is placed outside so as to be exposed to the wind, or when the air is blown, the lighting state of the lamp 6 changes greatly, giving a sensation like a candle. The circuit of the light source driving device shown in FIG. 4 generates a noise signal even if it is not exposed to wind, so even if it is kept indoors in the absence of wind, it fluctuates in lighting and gives a sensation like a candle. However, by taking the structure shown in FIG. 5, the lighting state changes under the influence of the wind, so that a more candle-like sensation is given.

FIG. 6 is a diagram showing another example of the illuminating device. In this case, a member 53 extending outward from the surface of the Zener diode 15 made of a material having good thermal conductivity is provided in place of the hole in FIG. 6, and when the surface of the member 53 is exposed to wind and the temperature changes, Is transmitted to the Zener diode 15.

FIG. 7 shows a battery 34 instead of the commercial AC power source.
It is a figure which shows the circuit structure of the light source drive device of 2nd Example which uses LED and uses LED33 instead of the incandescent light bulb. An oscillator 31 is provided and connected to the negative input of the operational amplifier 11 to obtain a sawtooth wave. Also, although the colors are different, LE
D33 is used, and it can be miniaturized. LED
You can also use a small miniature bulb instead of.

[0028]

As described above, according to the present invention,
It is possible to realize a light source driving device that can give a lighting feeling closer to a candle with an electric lighting tool.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of a light source driving device according to a first aspect of the present invention.

FIG. 2 is a diagram showing a basic configuration of an embodiment of an illuminating device using the light source driving device of the present invention.

FIG. 3 is a diagram for explaining generation of a driving pulse signal in the light source driving device of the present invention.

FIG. 4 is a circuit diagram showing a configuration of a light source driving device according to a first embodiment of the present invention.

FIG. 5 is a diagram showing an external appearance and an internal structure of a lighting device using the light source driving device according to the first embodiment.

FIG. 6 is a diagram showing an example of an external appearance and an internal structure of a lighting device using the light source driving device of the first embodiment.

FIG. 7 is a circuit diagram showing a configuration of a light source driving device according to a second embodiment of the present invention.

[Explanation of symbols]

 1. Noise source 2. Bandpass filter / gain control amplifier 3. Reference signal generation circuit 4. Comparator 5. Drive circuit 6. Light source (lamp) 7. Resistance 8. Resistance 9. Resistance 10. Resistance 11. Comparator 12. Diode 13. Speed-up capacitor 14. Capacitor 15. Zener diode for noise generation 16. Amplifier with bandpass filter 17. Amplifier with bandpass filter 18. Resistance 19. Resistance 20. Capacitor 21. Resistance 22. Resistance 23. Capacitor 24. Resistance 25. Capacitor 26. Gain adjustment trimmer resistor 27. Resistance 28. Zener diode 29. Capacitor 30. Bridge diode 31. Oscillator 32. Resistance 33. LED 34. Battery 50. Housing 51. Hole 52. Printed circuit board 53. Member e. Full wave rectified waveform d. Figure showing output of comparator e. Figure showing voltage waveform after bridge rectification f. Figure showing comparator input waveform after bridge rectification g. Diagram showing output pulse of comparator h. Figure showing generated sawtooth waveform i. Diagram showing noise after amplification

Claims (13)

[Claims] 1. A light source driving device for driving a light source, comprising: a noise generating source for generating random noise; and a driving circuit for driving the light source based on an output signal of the noise generating source. 2. The light source drive device according to claim 1, wherein the noise generation source changes noise generated according to a temperature change, and the noise generation source is arranged so as to be influenced by wind from the outside. 2. The light source driving device according to claim 1, wherein the light source driving device is housed in a housing having a hole, and the noise generating source is arranged to receive wind from the hole. Light source drive. 3. The light source drive device according to claim 1, wherein the light source drive device is housed in a housing, and a part of the noise generation source is exposed to the outside of the housing. 4. The light source drive device according to claim 1, wherein an output of the noise generating source is compared with a predetermined reference signal, and a pulse signal is generated based on a comparison result. A light source drive device comprising a circuit, wherein the drive circuit drives the light source based on a pulse signal output from the comparison circuit. 5. The light source driving device according to claim 4, wherein the reference signal periodically changes at a frequency higher than a frequency range of a signal output by the noise generation source, and the reference signal is output by the noise generation source. A light source drive device having a signal having an amplitude larger than the range of change of the signal to be generated. 6. A light source driving device for driving a light source, comprising: a noise generating source for generating random noise; and a driving circuit for driving the light source based on an output signal of the noise generating source. In, the noise source changes periodically at a frequency higher than the frequency range of the signal output, and compared with a predetermined reference signal having an amplitude larger than the change range of the signal output by the noise source,
A light source drive device comprising: a comparison circuit that generates a pulse signal based on a comparison result, wherein the drive circuit drives the light source based on the pulse signal output from the comparison circuit. 7. The light source drive device according to claim 1, wherein the noise generation source amplifies a zener voltage generated by a zener diode, a power supply circuit for supplying a current to the zener diode. A light source drive device comprising an amplifier circuit, and the output of the amplifier circuit is output as noise. 8. The light source drive device according to claim 1, wherein the noise source is a thermistor, a power supply circuit for supplying a current to the thermistor, and an end portion of the thermistor. A light source drive device including an amplifier circuit for amplifying the voltage to be output, and the output of the amplifier circuit is output as noise. 9. The light source driving device according to claim 7, further comprising a gain adjusting means for adjusting the gain of the amplifier circuit. 10. The light source driving device according to claim 1, wherein a filter for removing a signal having a predetermined frequency or lower and a signal having a predetermined frequency or higher among the signals generated by the noise source. A light source driving device including a circuit. 11. The light source drive device according to claim 10, wherein the filter circuit is a bandpass filter that passes signals in a frequency range of 0.1 Hz to 10 Hz. 12. A fluctuation signal generation device, wherein a 1 / f fluctuation signal generation source generates a 1 / f fluctuation signal and a generation of the 1 / f fluctuation signal generation source when the frequency is f. And a filter circuit for removing a signal having a frequency equal to or lower than a predetermined frequency or a signal having a frequency equal to or higher than a predetermined frequency. 13. The fluctuation signal generating device according to claim 12, wherein the filter circuit is 0.1 Hz to 10 H.
A fluctuation signal generation device that is a bandpass filter that allows signals in the z frequency range to pass.