JPS58172898A - Device for firing discharge lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lighting device for a discharge lamp, and particularly to means for preheating electrodes at the time of starting the lighting device.

FIG. 1 is a circuit diagram showing an example of a conventional discharge lamp lighting device for lighting a discharge lamp at high frequency.

In Figure 1, (1) is a commercial AC power supply, (2) is a rectifier that receives the commercial AC power supply and rectifies the AC voltage, and (3)
is a self-excited push-pull type transistor inverter that converts the pulsating current voltage rectified by the rectifier (2) into a high-frequency voltage, and (4) is the transistor inverter (3).
) The preheating electrode (4) lights up by inputting the high-frequency output voltage of
It is a fluorescent lamp with aL (4b).

Next, the configuration of the transistor inverter (3) will be explained.

The positive output end of the rectifier (21) is connected to a harmonic choke coil (
5) through a pair of leaky output transformers (6)
The rectifier (2) is connected between the next winding (L (6b)
) is connected to a pair of transistors (7a) and (z
b) is connected to the emitter of

The bases of these transistors (7a) and (yb) are connected to both ends of the base winding (6C) of the output transformer (6), and the base resistances (aa) and (
ab) to the resistor (9) and the emitter of the transistor a9. The above transistors (7a), (7
The collectors of transistors (7a) (b) are connected to one end of the primary winding (6aL (4b)), and both transistors (7a) (
A resonance capacitor all is connected between the collectors of 7b).

Also, on the primary side of the output transformer (6), there is a primary winding k.
(6a), (6b), Base winding (60) Auxiliary winding at O-hoka! (6(1) and the output winding (6θ) on the secondary side.
, 11i pole windings (4f), (6g). One end of the auxiliary winding (6d) is connected to the anode of the rectifier diode (2). The cathode of ifi diode 0 is for plain paper 1.
The other end of the auxiliary winding (6 slopes is connected to the other end of the smoothing capacitor l and the auxiliary winding is
m II O4+. The positive side output terminal of the auxiliary plane tkwr source αYang is connected to the collector of the transistor αS, the negative side is connected to the negative side output terminal of the rectifier (2), and the resistor αe is connected to the pace of the transistor α9. A resistor (91, DI is connected to the other end of the α port, and a resistor a1
The other end is connected to the positive output end of the rectifier (2).

On the other hand, the output winding (6e) is for lighting a fluorescent lamp (4) as a discharge lamp, and the output winding (6f) is for lighting a fluorescent lamp (4) as a discharge lamp.
) and (6g) are for preheating or heating the preheating electrodes (4a) and (4b).

Next, the operation of the conventional discharge lamp lighting device configured as described above will be explained with reference to FIG. 2. FIG. 2 is a waveform diagram of each part shown in FIG. 1.

When the commercial AC power supply 0) is applied, the commercial AC voltage shown in Fig. 2 (a) is rectified by the rectifier (2) (Fig. 2 (1) l).
The pulsating DC voltage shown by is the transistor inverter (3)
This voltage is applied between the collector and emitter of the transistor (7a)j (7b) through the harmonic choke coil (5) and the primary winding (6a) or (6b). At the same time, paste ta is supplied from the positive output end of the rectifier (21) to the transistors (7a) and (7b) via the resistor α(1, +91) and the base resistors (aa) and (ab).

At this time, due to a slight imbalance in the zero circuit, collector current begins to flow to either one of the transistors (7a) and (zb), and the transistor inverter (3) performs self-oscillation operation due to the action of the base winding (6c). , each winding of the output transformer (6) has a frequency of, for example, 2Q KHz to 4
A high frequency voltage of about 0 KHz as shown in TCI in FIG. 2 (the dipping edge indicates an envelope) is generated. and auxiliary winding (
The chest wave voltage generated in step 6d) is rectified by rectifier diode α2 and smoothed by smoothing capacitor a3.
or between the collector and emitter of the transistor α9 via the resistor (8b) and the pace emitter of the transistor (7b). On the other hand, the transistor G9 is connected to the resistor α1. Since the pulsating pace current is supplied through a5, = a device (2
), the emitter of the transistor αS and the transistor (71L) t or (7b
) is as shown in Figure 2 (C).

Transistor (7a) or (7b) from auxiliary power supply α4
) is supplied with a pace current sufficient to light up the light emitting lamp (4), and the light emitting lamp (4) lights up. By the way, the above +
Connect the resistor (II, +91
The pace current supplied to the transistors (7a), r7b) via the base resistors (8a), (8b) is a current for starting the numbering of the transistor inverter (3), and the pace current 11 is the current supplied to the transistor (7a), r7b) through the base resistors (8a), (8b). This is very small compared to the pace current supplied from the α4.

Also, when the light emitting lamp (4) is lit, the lamp current increases.

The lamp voltage is represented by the force 2 (al, (f) (A
The line shows the envelope), and since the output transformer (6) is of the leakage type, each winding pressure on the secondary side also has a waveform similar to that of the lamp voltage, and at this time, the preheating electrode (
4a), (4b) to properly heat the electrode winding (b).
f) and (bg) can be designed. In the figure, the phase (θ0) indicates the zero-imaginary phase of the voltage of the commercial AC source (11), and the 1 phase (
01) indicates the re-ignition phase of the light emitting lamp (4).

By the way, when starting a discharge lamp with a high frequency power source, compared to starting it with commercial AC voltage.

It is known that the starting voltage increases to 9%, and the rate of increase is remarkable at low temperatures. For this reason, the output voltage of a device for lighting a discharge lamp at a high frequency is set to be extremely high.

Therefore, in the conventional discharge lamp lighting device shown in Fig. 1, under normal conditions such as room temperature, when the commercial source fi1 is applied, the preheating of the fluorescent lamp (4) is either % pole (4a) l (41)) or medium. The fluorescent lamp (4) starts instantly without molecular heating. Therefore, it is easy to cause a so-called cold start. Fluorescent light (4
) The preheating electrodes (4a) and (4b) of the fluorescent lamp (4) are significantly worn out, resulting in a shortened lifespan of the fluorescent lamp (4).

This invention was made in order to eliminate the above-mentioned conventional problems.The discharge lamp is not lit for a set period of time after the power is turned on, and after the preheating electrode is heated by the intermediate molecules, the discharge lamp is started and discharged. A discharge lamp lighting device that prevents cold starts when starting lamps and extends the life of the discharge lamp.
*The purpose is to provide.

Hereinafter, the third embodiment of the discharge lamp lighting device of the present invention will be described.
This will be explained based on the diagram and FIG.

FIG. 3 is a circuit diagram showing the configuration of one embodiment.
The figure is a waveform diagram of each part of FIG. 3. In Figure 3, the first
The same or corresponding parts as in the figures will be described with the same reference numerals.

In Fig. 3, one end of the resistive surface is connected to the positive output terminal of the rectifier (2), and the other end is connected to one end of the voltage dividing resistor +Ill.
The other end of the voltage dividing resistor α is connected to the negative output end of the rectifier (2). The cand of the first constant voltage diode αl is connected to the contact between the resistive surface and the voltage dividing resistor αυ, and the anode thereof is connected to the base of the first transistor (2). The emitter of the first transistor wire is connected to the negative output terminal of the rectifier (21), and the collector is connected to the contact point of the resistor (9), α·, Qe.

In addition, a charging resistor can is connected to the positive output terminal of the auxiliary power supply α, and a capacitor @ is connected in series with this, and one side of this capacitor @ is connected to the negative output terminal of the auxiliary power supply +141. . Further, at the contact point between the charging resistor T211 and the capacitor, a cand of a second constant voltage diode (C) has an anode connected to the base of the second transistor @. The voltage dividing resistor A-stage is connected between the collector and emitter of the second transistor &41, and the second transistor (2
) is connected to the negative output terminal of the auxiliary power supply aa. The above is the configuration of the starting circuit (c), but the other circuit configuration of this discharge lamp lighting device is the same as the circuit configuration of FIG. 1.

Next, the operation of the discharge lamp lighting device of the present invention configured as above will be explained.

When the commercial AC power supply ill is applied, the commercial AC voltage shown in Fig. 4 (al) is rectified by the rectifier (2), and the pulsating DC voltage shown in Fig. 4 (bl) is applied to the transistor inverter (3). At this time, the second transistor 1214+ is OFF, so the pulsating DC voltage obtained by dividing the pulsating DC voltage by the resistor +I is applied to both ends of the 1-part voltage resistor α. In each cycle of the DC #L voltage of this divided pulsating current, the first transistor circle is ON during the period from phase (θ2) to phase (θ3) exceeding the Zener voltage (VZ) of the first constant voltage diode. Therefore, rectifier (2)
With reference to the potential at the negative output terminal of , the terminal voltage of the voltage dividing resistor α and the collector-emitter voltage of the transistor (to) are as shown in FIG. 4(C) and ((11), respectively.

Therefore.

The section from phase (θ2) to phase (θ5) is rectifier (2).
Since no base current is supplied to the transistors (7a) and (7b) from the positive output terminal of (A high frequency voltage as shown in fl is generated. This island wave electric wave generated in the auxiliary winding (6d) -
The pressure is rectified by the ta diode Q15, and the smoothing capacitor (1
The DC voltage of the auxiliary DC power supply a4 smoothed by 3 is connected to the base resistor (8a) and the base/emitter of the transistor (7a) or the resistor (8b) and the transistor (7'b) +7)
The collector of the transistor 4 through the base and emitter.
applied between the emitters. However, one of the resistors αυ connected to the base of the transistor α has a phase (θ2)
Since it is connected to the collector of the first transistor (to) which is ON in the period from to phase (θ3), the potential of the negative side output terminal of the rectifier (2) is used as a reference. The voltage between the emitter of the transistor and the emitter of the transistor (7a) or (7b) is as shown in FIG. za).

The pace current supplied to (7b) has a phase (
Since the voltage is zero in the interval from θ2) to phase (θ5), a voltage as shown in FIG. 4(f) is generated in each winding of the output transformer (6). The above operations are performed instantaneously after the commercial AC power supply (11) is turned on.

In this state, the fluorescent lamp (
4) The phase (θ2) or the phase (0
5), and at this time, preheat electrodes (4a)j (4b
) to a suitable voltage, e.g. 3.8v to 4.2v.
By setting the electrode windings (4f) and (6g) so that the aa
).

(4b) can be preheated.

On the other hand, the capacitor ■ is photoelectrically connected from the auxiliary blood flow power source Q41 through the photoresistance, but if the voltage of the capacitor ■ exceeds the Zener voltage of the second constant voltage diode, the second
First transistor iON.

The terminal voltage of the voltage dividing resistor tJI is equalized by the first voltage regulator diode Q9.
The Zener voltage becomes lower than 1, and the first transistor is turned off.
F. When this happens, the operation line of the transistor inverter (3) becomes similar to the operation of the conventional example described above, and a high frequency voltage as shown in Fig. 2 (di) is generated in each winding of the output cadence (6), and the fluorescent lamp ( 4) lights up.Commercial AC Electric Power Co., Ltd.
The time it takes to turn on the fluorescent lamp (4) after turning on the charging resistor Q1 (, capacitor ■).

The second constant voltage diode θ can be appropriately designed.

In order to properly set the preheating electrode (4aL (4b)) after the fluorescent lamp (4) is immersed, the oscillation frequency of the transistor inverter (3) is used before and after the fluorescent lamp (4) is immersed. ,
An impedance such as a coil or a capacitor may be inserted in series with the electrode winding (6f), the preheating electrode (4a), the electrode winding (6g), and the preheating electrode (4b).

By the way, the input voltage of the transistor inverter (3) may be a voltage obtained by smoothing the pulsating DC voltage of FIG. 2(b) to some extent, and the auxiliary blood flow power supply Q4 of the transistor inverter (3) is limited to this embodiment Instead, the power source for charging the -* capacitor is not limited to the auxiliary n current 11 source α4; for example, it may be from the output of the L unit (2). Further, the transistor inverter (3) may be of a negative type or separately excited type.

As mentioned above, this invention has 1! The preheating electrode of the discharge lamp is sufficiently preheated for a set period of time after the power is turned on, and then the discharge lamp is turned on and the pre-#L electrode can be appropriately heated at the same time, which prevents a cold start when starting the discharge lamp. There is a pickle that can prolong the life of the product.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing an example of a conventional discharge lamp lighting device, Fig. 2 is a waveform diagram for illustrating the circuit operation of Fig. 1, and Fig. 3
The figure is a circuit diagram of one embodiment of the discharge lamp lighting device of the present invention, and FIG. 4 is a waveform diagram for explaining the circuit operation of FIG. 3. (1)... Commercial AC 11 source, (2)... Rectifier, (
3)...Transistor inverter, (4)...Fluorescent lamp, (4aL(4b)...Preheating'fi pole, (5)
-...Harmonic choke coil, (6)...Output transformer, '(7aL (7-b), a...Transistor. (aa), (ab)-Heath resistance, fsl, '
Ql, (IB, 0?+...resistance, 01)...
・Condenser for joint photography, G-to, auxiliary DC power supply. 0... Voltage dividing resistor, α9... 1st leg voltage diode,
CIG...1st) U7ji, kll...photoresistance, so...capacitor,...second leg voltage diode, ---second transistor, fault...starting circuit . 7;C&, the same reference numerals in the figures indicate the same or corresponding parts. Agent Kuzuno ig -

Claims (1)

[Claims] A transistor inverter includes a commercial AC power source, a rectifier that receives the commercial AC power source and rectifies the AC voltage, a leakage transformer that converts the pulsating DC voltage rectified by the rectifier into a high frequency voltage, and this high frequency voltage. In a device consisting of a discharge lamp having a preheating electrode that is turned on by inputting the voltage, an electrode winding of a preheating device that performs preheating of the discharge lamp and preheating of the pole and electric heating is provided on the secondary side of the leakage type transformer. a voltage dividing resistor that divides the output voltage of the rectifier, and a first transistor that conducts in a period exceeding the Zener voltage of the first constant voltage diode in each cycle of the pulsating DC voltage that is the output of the rectifier; A first wJ including a second transistor connected to conduct when the voltage of the capacitor charged through the charging resistor exceeds the Zener voltage of the second voltage regulator diode and short-circuit both ends of the voltage dividing resistor.
A discharge lamp lighting device characterized in that the circuit is provided in the transistor inverter described above.