GB2025715A - Lighting circuit - Google Patents
Lighting circuit Download PDFInfo
- Publication number
- GB2025715A GB2025715A GB7829688A GB7829688A GB2025715A GB 2025715 A GB2025715 A GB 2025715A GB 7829688 A GB7829688 A GB 7829688A GB 7829688 A GB7829688 A GB 7829688A GB 2025715 A GB2025715 A GB 2025715A
- Authority
- GB
- United Kingdom
- Prior art keywords
- circuit
- photo
- lighting
- transistor
- light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/72—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices having more than two PN junctions; having more than three electrodes; having more than one electrode connected to the same conductivity region
- H03K17/725—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices having more than two PN junctions; having more than three electrodes; having more than one electrode connected to the same conductivity region for ac voltages or currents
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/78—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled
- H03K17/79—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled controlling bipolar semiconductor switches with more than two PN-junctions, or more than three electrodes, or more than one electrode connected to the same conductivity region
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/78—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled
- H03K17/795—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled controlling bipolar transistors
- H03K17/7955—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled controlling bipolar transistors using phototransistors
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B39/00—Circuit arrangements or apparatus for operating incandescent light sources
- H05B39/04—Controlling
- H05B39/08—Controlling by shifting phase of trigger voltage applied to gas-filled controlling tubes also in controlled semiconductor devices
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B39/00—Circuit arrangements or apparatus for operating incandescent light sources
- H05B39/09—Circuit arrangements or apparatus for operating incandescent light sources in which the lamp is fed by pulses
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
A circuit for causing the luminous intensity of an incandescent lamp 12 to vary like a candlelight comprises a control means 13 including a phototransistor or resistor 23 and a plurality of relaxation oscillators 14 arranged to oscillate with substantially equal frequencies. Each oscillator comprises a neon tube 20 and the photo-transistor or resistor is adapted to receive the light emitted by each of the neon tubes, whereby the luminous intensity of the light emitted by the lamp 12 is continuously and irregularly varied. <IMAGE>
Description
SPECIFICATION
Lighting circuit
This invention relates to a lighting circuit for lighting an incandescent lamp like a candlelight, and more particularly to a circuit which can continuously and irregularly vary the brightness of a lamp.
An illuminating device which uses a candle or candles has little utility because of the possibility of a fire starting and the limited lighting time of a candle.
Manly illuminating devices of such kind have been changed to devices having electric lamps. But, such illuminating devices are irksome, because an electric lamp cannot easily vary the luminous intensity of the light emitted by the lamp.
Therefore, electric lighting devices which can change luminous intensities have been developed using mechanical or electrical methods. In the mechanical methods, the devices become complicated and expensive structures. In the electrical methods, it is not possible to obtain a device which can continuously and irregularly vary the luminous intensity of a light. A device which has a plurality of electric lamps in an envelope and which can change the number of lighting lamps is known. A device shown in Japanese Official Patent Gazette for Public
Disclosure of Application No. 47-44871 has an incandescent lamp and a thyristor connected in series accross an alternating current source and an oscillator supplying gate pulses to the thyristor to energize the lamp. The device can vary the luminous intensity of a light only constantly or periodically.
Accordingly, it is an object of this invention to provide a circuit for lighting like a candlelight which can vary the luminous intensity of a light continuously and irregularly.
Another object of this invention is to provide a circuit for lighting like candlelight which is simple and inexpensive.
According to the invention, there is provided a lighting circuit for lighting like a candlelight a lighting means in the form of at least one incandescent lamp, comprising a plurality of oscillators arranged to oscillate with substantially equal frequencies, and means for controlling an electric current flowing through said lighting means in accordance with the composite output of said oscillators. Each oscillator may be a relaxation oscillator having a neon tube, and the circuit may comprise a photo-sensitive element, such as a photo-transistor, which is adapted to receive a composite light of the lights emitted by the neon tubes, whereby the photo-sensitive element controls the electric current flowing through the lighting means.
,This invention also provides a circuit for lighting like a candlelight a lighting means which comprises at least one incandescent lamp, comprising a phototransistor positioned to receive a light which varies in luminous intensity and arranged to control and electric current flowing through said lighting means.
The light may be a composite light of a plurality of lights. The light may be a composite light of the lights emitted by a plurality of neon tubes.
An embodiment of the invention will now be described by way of example and with reference to the accompanying drawing, wherein the sole figure is a diagram of a circuit according to the invention.
In an embodiment of this invention shown in the figure, a pair of terminals 10 and 11 are provided for connection to a conventional alternating current electric source. A lighting means in the form of an incandescent lamp 12 is connected between the terminals 10 and 11.
13 generally designates a control means which has three relaxation oscillatiors 14. Each oscillator is connected between the terminals 10 and 11 and has a direct current supplied thereto by a diode 15 and a condenser 16. Each oscillator 14 is composed of a resistor 17, a condenser 18 and a neon tube 20 which repeatedly lights on and off. The oscillatores 14 are made so as to have substantially equal frequencies.
But, very small differences are irregularly created because the frequency of each oscillator 14 is independently changed by a small amount owing to various conditions, for example, the temperature of the air surrounding the oscillator and small variations in the voltage of the electric source. Therefore, the composite light of the lights emitted by the neon tubes 20 irregularly exhibits a beat phenomemon which means that the luminous intensity of the composite light irregularly varies from a Isarge value at one time to a small value at another time.
The control means 13 has a bidirectional triode thyristor (triac) 21 which is connected between the lamp 12 and the terminal 11. A bidirectional diode thyristor (diac) 22 is connected to the gate electrode of the triac 21 for switching of the traic 21.
The control means 13 also includes a phototransistor or photo-resistor 23 which is adapted to receive the composite light emitted by the neon tubes 20, whereby the resistance thereof is irregularly varied by the luminous intensity of the composite light. A condenser 24 is connected in series with the photo-transistor 23. The circuit composed of the photo-transistor 23 and the condenser 24 is connected in parallel with the triac 21, and the connecting point between the photo-transistor 23 and the condenser 24 is connected to the diac 22. A resistor 25 is connected in parallel with the photo-transistor 23. Therefore, the current flow angle of the thyristor 21 for supplying an alternating current to the lamp 12 is controlled by the varying resistance of the photo-transistor 23.The photo-transistor 23 has small time lag in the variation of its resistance; therefore it does not sensitively respond to the lighting off and on of the neon tubes 20, and it responds to an averaged value of the composite light in a short time interval. The resistor 25 makes it possible that the lamp 12 can be lighted with a small luminous intensity even at a time when the resistance of the photo-transistor 23 becomes large.
Thus, the luminous intensity of the light emitted by the lamp 12 can be continuously and irregularly varied like a candlelight.
In this invention, various modifications may be made. For example, it is possible that the lighting means can include a plurality of laps connected in series and/or parallel. A plurality of oscillators which are not relaxation oscillators can be used for con trolling a current flowing through a lighting means by a composite output of the oscillators.
The foregoing is of course course considered as illustrative only of the principle of the invention.
Obviously, numerous modifications and variations of the present invention are possible in the light of the above teachings.
Claims (9)
1. A lighting circuit for lighting like a candlelight a lighting means in the form of at least one incandescent lamp, comprising a plurality of oscillators arranged to oscillate with substantially equal frequencies, and means for controlling an electric current flowing through said lighting means in accordance with the composite output of said oscillators.
2. A circuit as claimed in Claim 1, wherein each of said oscillators is a relaxation oscillator having a neon tube, and comprising a photo-sensitive element arranged to receive the composite light of the lights emitted by said neon tubes and to control said electric current flowing through said lighting means.
3. A circuit as claimed in Claim 2 wherein said photo-sensitive element is a photo-transistor.
4. A circuit as claimed in Claim 3, for connection to an alternating electric current source, comprising a bidirectional triode thyristor connected in series with said lighting means, a resistor connected in parallel with said photo-transistor, a condenser connected in series with said photo-transistor, the circuit composed of said photo-transistor and said condenser being connected in parallel with said bidirectional triode thyristor, and a bidirectional diode thyristor connected between the gate electrode of said bidirectional triode thyristor and the connecting point between said photo-transistor and said condenser.
5. A circuit for lighting like a candlelight a lighting means which comprises at least one incandescent lamp, comprising a photo-transistor positioned to receive a light which varies in luminous intensity and arranged to control an electric current flowing through said lighting means.
6. A circuit as claimed in Claim 5, wherein said light is a composite light of a plurality of lights.
7. A circuit as claimed in Claim 6, wherein said light is a composite light of lights emitted by a plurality of neon tubes.
8. A circuit as claimed in Claim 7, comprising a plurality of relaxation oscillators arranged to oscillate with substantially equal frequencies, each relaxation oscillators being arranged to light a respective neon tube.
9. A lighting circuit substantially as hereinbefore described with reference to the accompanying drawing.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP222777 | 1977-01-12 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2025715A true GB2025715A (en) | 1980-01-23 |
| GB2025715B GB2025715B (en) | 1982-09-02 |
Family
ID=11523459
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7829688A Expired GB2025715B (en) | 1977-01-12 | 1978-07-13 | Lighting circuit |
Country Status (3)
| Country | Link |
|---|---|
| DE (1) | DE2830682A1 (en) |
| FR (1) | FR2431092A1 (en) |
| GB (1) | GB2025715B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2347563A (en) * | 1999-03-02 | 2000-09-06 | James Kembal Davidson | Flame flicker simulation |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE9308615U1 (en) * | 1993-06-09 | 1993-08-26 | Lünow, Rosemarie, 50670 Köln | Portable electric light |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3495128A (en) * | 1966-01-07 | 1970-02-10 | Douglas G Gresham | Random power gate |
| US3710182A (en) * | 1971-04-30 | 1973-01-09 | Reenen R Van | Circuit producing candle-flicker light output from lamp |
-
1978
- 1978-07-12 DE DE19782830682 patent/DE2830682A1/en not_active Withdrawn
- 1978-07-13 FR FR7821021A patent/FR2431092A1/en active Granted
- 1978-07-13 GB GB7829688A patent/GB2025715B/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2347563A (en) * | 1999-03-02 | 2000-09-06 | James Kembal Davidson | Flame flicker simulation |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2830682A1 (en) | 1980-01-24 |
| FR2431092A1 (en) | 1980-02-08 |
| FR2431092B1 (en) | 1984-02-24 |
| GB2025715B (en) | 1982-09-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4593232A (en) | Flame simulating apparatus | |
| US3435286A (en) | Plural lamps for simulating a candle flame | |
| US3422309A (en) | Fluorescent light dimming system | |
| US4159442A (en) | Circuit for lighting like candlelight | |
| US20060125420A1 (en) | Candle emulation device | |
| US3803452A (en) | Lamp control circuit | |
| JPS5788318A (en) | Electronic meter for automobile | |
| KR970028047A (en) | A lighting device and a frame made by attaching the lighting device | |
| US3862434A (en) | Christmas tree lighting control | |
| US11412727B2 (en) | LED lamp array for insect trap | |
| US3793531A (en) | Electronic tree light controller | |
| KR100420233B1 (en) | Circuit device | |
| GB2025715A (en) | Lighting circuit | |
| FR2346935A1 (en) | Triac dimmer for electric lamp - has bayonet fittings to fit between lamp and socket with variable resistor control and on-off twist switch | |
| JPS60171030A (en) | Eyesight inspector | |
| US2558747A (en) | Electric lighting system | |
| GB2060852A (en) | Decorative multi-coloured lamps | |
| SE8200077L (en) | LIGHTING SYSTEM WITH A COMPACT ELECTRIC LIGHTING UNIT | |
| FR2275639A1 (en) | Street lamp or traffic sign - electric light switched on according to ambient light | |
| GB2103777A (en) | Lamp having a simulated flame | |
| KR900000983Y1 (en) | Automatic variable color lighting device | |
| US4902939A (en) | Display circuit | |
| GB2045415A (en) | Decorative lighting system | |
| SU828443A1 (en) | Illumination device | |
| JP2968483B2 (en) | Illuminator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |