CN2824502Y

CN2824502Y - Electronic ballast starting circuit

Info

Publication number: CN2824502Y
Application number: CN 200520063714
Authority: CN
Inventors: 黄甜仔
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-08-31
Filing date: 2005-08-31
Publication date: 2006-10-04
Anticipated expiration: 2015-08-31

Abstract

The utility model relates to an electronic ballast starting circuit, which is suitable for fluorescent lamps of lamp filament current breaking technology. A starting resistor R is connected with any one point of A point or B point of both ends of a lamp tube Rf after an output loop of an electron ballast passes through a lamp filament, the other end of the resistor R is connected with a trigatron D, and the other end of the trigatron D is connected with the base of a transistor in a resonance circuit or a field effect pipe grid electrode loop; a capacitor C is connected in parallel with a node of the resistor R and the trigatron D and a DC negative voltage of the electron ballast. When the electron ballast is not connected with the lamp tube or the lamp tube is poor in contact, even though a power supply is connected, the A point or the B point of the output end of the lamp tube has no voltage, the starting circuit can not generate a triggering voltage, the resonance circuit can not work and thus an anomaly state of lamp disconnection of the electron ballast is favorably protected.

Description

A kind of electric ballast start-up circuit

Technical field

A kind of electric ballast start-up circuit is in particular for the electronic ballast for fluoresent lamp of filament cutout technology.

Background technology

The T5 fluorescent lamp has the installing space littler than other serial fluorescent tubes, is the novel illumination product that can reflect miniaturization and high efficiency trend a kind of while.In order to make fluorescent tube have longer useful life and the lux maintenance of Geng Gao, adopt CUF-OFF filament cutout technology, promptly only in lamp pipeline start up by preheating process, there is electric current to flow through filament and fluorescent tube flows through the electric current of filament after starting and is cut off, thereby make lamp electrode place keep lower working temperature, lamp tube service life is greatly improved, and can reduces the consumed power of fluorescent tube.Therefore T5 fluorescent lamp and illuminator thereof are subjected to various countries' illumination merchants' favor, have very big market.But because filament cutout technology is in circuit of electronic ballast; be that resonant capacitance is not sealed in connection filament two terminal circuits and inserts the lamp tube ends another side; to reach the purpose that fluorescent tube filament behind pipeline start up by preheating does not have electric current to flow through; but brought not lamp open circuit abnormal condition protection problem simultaneously with fluorescent tube or fluorescent tube loose contact; protection is done well; the phenomenon that moment burns electric ballast will occur starting, thereby seriously influence the development of filament cutout technology.

The utility model content

In order to overcome the phenomenon that existing electric ballast adopts filament cutout technology to burn easily under lamp open circuit abnormality, the utility model provides a kind of and can not be with under fluorescent tube or the fluorescent tube loose contact situation, the electric ballast failure of oscillation is not worked, thereby has guaranteed the safe in utilization of electric ballast.

The technical scheme that its technical problem that solves the utility model adopts is:

In electric ballast, start-up circuit is made up of starting resistance R, capacitor C, diac D, wherein starting resistance R is connected on the electric ballast output loop through fluorescent tube Rf two ends behind the filament wherein on 1 A point or the B point, when not meeting fluorescent tube Rf, start-up circuit can not produce trigger voltage, resonant circuit is not worked, and has reached the purpose of not damaging electric ballast when lamp open circuit abnormality.

Description of drawings

Below in conjunction with drawings and Examples the utility model is further described.

Fig. 1 is principle A figure of the present utility model.

Fig. 2 is principle B figure of the present utility model.

Embodiment

As shown in Figure 1, electric ballast is made up of the whole circuit 1 of bridge, resonant circuit 2, high frequency choke ballast inductance L, resonant capacitance C1, fluorescent tube Rf and preheating device PTC etc., starting resistance R be connected on the electric ballast output loop through fluorescent tube Rf two ends behind the filament wherein on 1 A point, the other end of starting resistance R receives the transistor base in the resonant circuit 2 or the grid return of field effect transistor by diac D, capacitor C is connected in parallel between the node and direct voltage of resistance R and diac D, constitutes the start-up circuit of electric ballast.When not meeting fluorescent tube Rf, even energized, owing to do not have voltage on the A point, start-up circuit can not produce trigger voltage, and resonant circuit is not worked, thereby guarantees electric ballast safe in utilization when lamp is opened a way abnormality.When connecting fluorescent tube Rf, energising, direct-flow positive voltage passes through capacitor C 1, following filament output terminals A point, resistance R, diac D, arrives the base stage of switching transistor, when the voltage on the electric capacity reaches the trigger voltage of diac D, transistor base obtains voltage and conducting, resonant circuit 2 enters normal operating conditions, and makes the fluorescent lamp operate as normal.

In Fig. 2, starting resistance R is connected on another output B point of fluorescent tube Rf filament, receive transistor base or fet gate loop in the resonant circuit 2 by diac D, capacitor C is connected in parallel between the node and negative DC voltage of resistance R and trigger tube D, constitute the start-up circuit of electric ballast, its operation principle is the same with Fig. 1.

Claims

1. electric ballast start-up circuit, starting resistance R is connected with each end of capacitor C and diac D, the other end of trigger tube is connected on transistor base or the fet gate loop in the resonant circuit, the other end of capacitor C is connected on the electric ballast negative DC voltage, it is characterized in that: starting resistance R is connected on the electric ballast output loop through fluorescent tube Rf two ends behind the filament wherein on 1 A point or the B point.