CN201134966Y

CN201134966Y - DC fluorescent lamp without radiation and stroboscopic effect

Info

Publication number: CN201134966Y
Application number: CNU2007201466752U
Authority: CN
Inventors: 贺俊峰
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-04-16
Filing date: 2007-04-16
Publication date: 2008-10-15
Anticipated expiration: 2017-04-16

Abstract

A non radiation non strobe direct current fluorescent lamp which is used under the 220V alternating current is formed by a capacitive voltage division circuit, a bridge type rectification filter circuit, a high voltage starting circuit and an electron filter constant current circuit. The 220 V current is changed into direct current with certain ripple through conducting with the rectification and filtering after being divided by a capacitance, the direct current is added on the two ends of a light tube through a secondary coil of a high frequency transformer after passing through an electronic filter, and the starting circuit which is formed by a DB3 trigger diode, a switch triode and a high frequency transformer can generate high voltage which is added on the two ends of the light tube at the moment of turn-on, thereby fast lightening the light tube. The utility model has simple circuit structure, low cost and high stability. Since the starting circuit not only provides voltage, but also has stronger loading ability, the lamp filament on the cathode of the light tube is not warmed up, and cold-starting can be directly operated, thereby prolonging the service life of the light tube. The utility model is especially suitable to be used on desk lamps.

Description

Radiationless DC fluorescent lamp without stroboflash

Technical field

The utility model relates to a kind of radiationless DC fluorescent lamp without stroboflash that uses under alternating current 220V, especially can thoroughly solve the radiation to human body under the state of turning on light of the present high frequency fluorescent desk lamp that generally uses.

Background technology

At present, generally the lighting of Shi Yonging is exactly the high-frequency florescent lamp that adopts electric ballast work, comprises that the electricity-saving lamp of penetration and promotion recent years and various desk lamp nearly all are the high-frequency electronic ballasts that adopts.Popularizing of high-frequency florescent lamp solved the original old-fashioned drawback of leaning on the flicker from fluorescent lighting of inductance type ballast work under the 50HZ frequency really, and it has also improved the power factor of lamp simultaneously, has saved electric energy, has therefore obtained extensive approval.But high-frequency florescent lamp technology problem when being used for desk lamp does not just have so simple, be not difficult to know that from electromagnetic theory high-frequency florescent lamp causes high radiation to be inevitable owing to the high voltage high-frequency when working, because desk lamp is closer from human body in use, human body especially brain is directly exposed under its strong electromagnetic radiation.People have mostly ignored this problem all the time, may still for a long time be that harmful nothing is sharp certainly under the high dose electromagnetic radiation because radiation itself is to be not easy to be caused by the direct perception of people.

Existing people proposes multiple solution at the problems referred to above, mainly contains two big classes: the one, and adopt voltage multiplying rectifier to add the electronics filters solutions, the 2nd, adopt the high frequency transformation to add the electronics filters solutions.First kind of scheme be because the high pressure leakage problem is difficult to stable the use in practice, and second kind of scheme is more feasible, and a few producer radiationless desk lamp of direct current that put into production is arranged in the market, mostly is to adopt second kind of scheme.The result of factual survey is: high frequency radiation has solved really, but because the DC filtering technology not really reaches a standard, generally also has certain stroboscopic (50HZ).

Summary of the invention

Simultaneously can not produce new stroboscopic in order to solve above-mentioned high-frequency electronic ballast desk lamp to the radiation effect of human body, the utility model provides a kind of new scheme, the succinct working stability of this scenario-frame, but also can light modulation.

The utility model is achieved in that the 220V alternating current carries out rectifying and wave-filtering (capacitor filtering) and becomes the direct current that certain ripple is arranged behind capacitance partial pressure, this direct current through behind electronic filter again the secondary coil through high frequency transformer be added to lamp tube ends, the start-up circuit of being made up of DB3 diac, switch triode and high frequency transformer is added to lamp tube ends at the moment of energized generation high pressure lights fluorescent tube rapidly.Turn-off DB3 immediately by the feedback circuit that is connected the fluorescent tube negative pole end after the fluorescent tube conducting and trigger the source, fluorescent tube promptly enters stable DC operation state.

The utility model has adopted the DB3 diac to add the concussion source of switch triode as high voltage startup, makes circuit structure succinct, and cost reduces, and stability improves.Because this start-up circuit can not only provide high pressure, and stronger load capacity is arranged, therefore without the filament of preheat lamp tube cathode, directly cold start-up gets final product, can prolonging lamp tube service life.The utility model has improved the structure of electronic filter in addition, makes its filter effect better, and can also light modulation.

Description of drawings

Accompanying drawing is circuit theory diagrams of the present utility model.

Wherein: frame of broken lines 1 is the capacitance partial pressure circuit, and frame of broken lines 2 is current rectifying and wave filtering circuits, and frame of broken lines 3 is high-voltage starting circuits, and frame of broken lines 4 is electronic filtering circuit.

Embodiment

With reference to accompanying drawing, a kind of radiationless DC fluorescent lamp without stroboflash that under alternating current 220V, uses, the electronic circuit of this DC fluorescent lamp partly is made up of capacitance partial pressure circuit, bridge rectifier filter circuit, high-voltage starting circuit, electronic filtering constant-current circuit, fluorescent tube.Wherein high-voltage starting circuit is made up of resistance R 5, R6, capacitor C 2, diac DB3, switching tube VT1, transformer B, resistance R 7, resistance R 8, triode G1, diac DB3 one end connects the collector electrode that the VT1 base stage other end connects R5, C2 and G1, the emitter of G1 is connected with the current rectifying and wave filtering circuit negative pole, and this start-up circuit is to be attempted by electronic filtering constant-current circuit front end.Exchanging bleeder circuit that 220 volts of voltages form through capacitor C 1 and resistance R 1 is added to behind the bridge rectifier of being made up of rectifier diode D1, D2, D3, D4 through electrochemical capacitor EC1 filtering again and becomes direct current with certain ripple.Wherein capacitor C 3 is an input filtering electric capacity, and resistance R 1 and R2 all are safe discharge loops of electric capacity.C1, C3 requirement of withstand voltage are more than 400 volts.

Form high-voltage starting circuit by resistance R 5, R6, capacitor C 2, diac DB3, switching tube VT1, transformer B, resistance R 7, resistance R 8, triode G1, its course of work is: direct current charges to C2 by R5 after the energized, after the voltage of C2 reaches the conducting voltage of DB3, the DB3 conducting, the base stage that the voltage at C1 two ends is added to VT1 makes the VT1 conducting, and direct current (more than the 200V) flows through the L1 of transformer B after the R6 current limliting; C2 discharges into the conducting voltage that is lower than DB3 very soon, and VT1 ends, and C2 continues charging, discharge then, so circulation forms concussion, and the electric current that flows through the L1 both sides also and then forms the concussion electric current, produces high pressure (more than the 1000V) like this and make fluorescent tube FPL at instant igniting on the L2 of transformer B.Because this start-up circuit can not only provide high pressure, and stronger load capacity is arranged, therefore without the filament of preheat lamp tube cathode, directly cold start-up gets final product, can prolonging lamp tube service life.Fluorescent tube starts after-current through flow through fluorescent tube and produce a pressure drop on R9 of electronic filter 4, and this voltage is added to the base stage of triode G1 through R7, the G1 conducting, and the voltage on the C2 obtains discharging, and concussion stops.The electronic filtering constant-current circuit of being made up of triode VT2, adjustable resistance R4, resistance R 3, electric capacity EC2 plays the effect of stabling current.

Because this electronic filter constant-current circuit has adopted base stage to add the negative feedback mode of resistance, electrochemical capacitor EC2 directly receives the base stage of VT2, and feedback effects is good like this, and filter effect is also better.Regulate R4 and can regulate the electric current that flows through VT2, and then regulate the brightness of fluorescent tube.

Claims

1, a kind of radiationless DC fluorescent lamp without stroboflash that under alternating current 220V, uses, the electronic circuit that it is characterized in that this DC fluorescent lamp partly is by the capacitance partial pressure circuit, bridge rectifier filter circuit, high-voltage starting circuit, the electronic filtering constant-current circuit, fluorescent tube is formed, wherein high-voltage starting circuit is by resistance R 5, R6, capacitor C 2, diac DB3, switching tube VT1, transformer B, resistance R 7, resistance R 8, triode G1 forms, diac DB3 one end connects the VT1 base stage other end and connects R5, the collector electrode of C2 and G1, the emitter of G1 is connected with the current rectifying and wave filtering circuit negative pole, and this start-up circuit is to be attempted by electronic filtering constant-current circuit front end.

2, according to the said radiationless DC fluorescent lamp without stroboflash of claim 1, the positive pole that it is characterized in that the electric capacity EC2 in the above-mentioned electronic filtering constant-current circuit is directly to be connected on the base stage of triode VT2.