JPS6288293A - Discharge lamp starter - 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 [Technical Field] The present invention relates to a discharge lamp starting device that sequentially changes a starting pulse and applies it to a discharge lamp.

[Background Art 1 Conventionally, a discharge lamp starting VC device has been developed in which a discharge lamp such as a fluorescent lamp is started by an electronic circuit instead of a lighting tube.

Various improvements have been made to the starting performance of discharge lamps, but in all cases the pulse voltage applied to the discharge lamp is sufficient to light the discharge lamp.

In particular, in order to light the discharge lamp at a low temperature, a higher voltage pulse is required, so the pulse voltage to be applied is a high voltage so that the discharge lamp can be lit even at this low temperature. Therefore, a pulse at a low temperature has a higher voltage than the pulse voltage required at room temperature, and there is a problem in that applying this high voltage pulse to a discharge lamp at room temperature has a negative effect on the lamp life.

In addition, if the discharge lamp has a different wattage, such as 20W, 30W, or 40W, the pulse voltage that can be used to light the discharge lamp will be different. Therefore, if the same socket is used for each wattage discharge lamp, the above device may be installed incorrectly. Sometimes I do. For example, 40W, 1,000! - 20W starting device for 40W with constant design for Futaibu lighting fixture m
When coupled to the start socket of a check-type lighting lamp, the 40W starter is designed to produce a high pulsed voltage, which is higher than the pulsed voltage required for a 20W discharge lamp. will occur.

If this pulse is suddenly applied, an excessive pulse is applied to the 20W discharge lamp, which accelerates the blackening of the discharge lamp. In the opposite case, the pulse voltage may be insufficient and the discharge lamp may not start and turn on.

In order to eliminate the above-mentioned drawbacks, there is a conventional method in which the pulse voltage is gradually increased and applied to the discharge lamp as sporadic pulses.

FIG. 7(a) shows a circuit configuration of a conventional example, in which a ballast element 3 including an inductance is connected in series with the discharge lamp 4, and a main switch element 5 is connected in parallel with the discharge lamp 4.
and a control circuit 6 connected in parallel to the main switch element 5. Here, the main switch element 5 is a diode 5 as shown in FIG. 7(b) for easy explanation.
1. It is assumed that the circuit is composed of a series circuit of transistors 52.

Next, the operation of the conventional example will be explained. Now, when the power switch 2 is turned on and the AC power source 1 is connected, and the control circuit 6 starts operating, the transistor 52 of the main switch element 5 becomes conductive due to the signal from the control circuit 6, as shown in FIG. 8(a). , a current (2) flows in the forward direction of the diode 51, and both filaments (4a, 4b) of the discharge lamp 4 are preheated by a so-called half-wave as shown in FIG. 8(b). At a constant time +11'lAl (after preheating time), as shown in FIG.
interrupts the preheating current, and a transient phenomenon of the ballast element 3 generates a pulse voltage across the discharge lamp 4 as shown in FIG. 8(c). After further tl (at the start of preheating current flow),
Transistor 52 becomes conductive again, allowing current ■ to flow. After L2, the transistor 52 is again cut off and a pulse voltage is applied to the discharge lamp 4. Similarly, the transistor 52 becomes conductive.
Repeat the cutoff. The current cut off at this time is designed to gradually increase from a small current to a large current, and due to the transient phenomenon of the ballast element 3, the pulse voltage gradually increases from low voltage to high voltage, and the discharge lamp 4 When the voltage is applied, the discharge lamp 4 finally turns on. Incidentally, FIG. 8(c) shows the voltage V62 across the discharge lamp 4, and the broken line in the figure is the voltage waveform of the AC power supply 1.

In this method, the phase that connects and disconnects the normal current is the QF
gl/L, N5z-r, Ink 9R-Nail 4m
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Car I: held in 'rkn. However, in this method, the termination of the preheating current I (point P in Fig. 8(b)) may be incorrect due to changes in the power supply voltage, changes in the ambient temperature, variations in the inductance value of the ballast element 3, variations in the discharge lamp 4, etc. However, there is a drawback that the pulse voltage generated at this time also becomes unstable.

On the other hand, FIG. 9 shows an improved example in which the current flowing through the transistor 52 is cut off at the rising edge.

In other words, the rise of the current flowing through the transistor 52 is in the same phase as the power supply voltage, so the current is relatively stable.
Therefore, the generated pulse voltage becomes stable. However, in the process of pulse generation, the transistor 52 cuts off the current at the rise of the current, so the current flowing through the filaments 4a and 4b of the discharge lamp 4 is small, and the preheating power for the filaments 4a and 4b is insufficient. There are drawbacks.

FIGS. 9(a)-(c) correspond to FIGS. 8(a)-(c). OBJECT OF THE INVENTION] The present invention has been made in view of the above-mentioned problems.The purpose of the present invention is to make the starting point 1 of a discharge lamp common regardless of changes in ambient temperature, and to improve the software of the discharge lamp. To provide a discharge lamp starting device capable of starting and stably generating a pulse voltage.

[Disclosure 1 of the Invention The present invention provides a ballast element including an inductance inserted in series between a preheating discharge lamp and an AC power supply, and a main switch element connected in parallel between the non-power supply side terminals of the discharge lamp. and,
It consists of a control circuit that is connected in parallel to the main switch element and controls the main switch element, and the control circuit sets a preheating period in which the main switch element is conductive for a certain period of time after the power is turned on, and also performs preheating after the preheating period has elapsed. A period in which the main switch element is cut off at the point of current rise to generate a pulse across the discharge lamp, and a period in which the main switch element is made conductive to flow a preheating current to the discharge lamp are set alternately, and the main switch element is cut off. This feature is characterized in that the phase to be applied is set to gradually increase. This will be explained below using examples.

Figure 1(b) shows the basic circuit configuration of a lighting circuit using the discharge lamp starting device according to the present invention. The main switch element 5 is connected to a series circuit with the discharge lamp 4, and the control circuit 6 is connected in parallel to the main switch element 5. Although they are the same, the control circuit 6 has a feature.Control circuit 6
As shown in FIG. 2, the power synchronization signal detection circuit 7, preheating timer circuit 8, pulse generation signal circuit 9, pulse generation phase setting circuit 10, inter-pulse preheating timer circuit 11, pulse generation time timer circuit 12, main switch operation It is composed of a signal circuit 13, a basic oscillation circuit 14, and the like.

FIG. 3 shows a concrete circuit of the control circuit 6, and the operation of this embodiment will be explained using this concrete circuit and the waveform circuit of FIG. When the power supply voltage shown in FIG. 4(a) is applied to both ends of the discharge lamp 4 by turning on the power switch 2 in FIG.
As a result, pulses as shown in FIG. 4(b) are output. This pulse is applied by the preheating timer circuit 8, and the "H" output is maintained during the preheating time (time t1 in FIG. 4(c)). By this "H"H", the inter-pulse preheating timer circuit 11
The output of the pulse generation time timer circuit 12 becomes "H" as shown in FIG. 4(d), and the output of the pulse generation time timer circuit 12 becomes "H" as shown in FIG. 4(d). 4th output
The output of the main switch operation signal circuit 13 is held at L'' as shown in FIG.
”, the main switch element 5 is operated, and the filament 4a, 4b of the discharge lamp 4 is preheated as shown in FIG. 4(h) (until time L1 in FIG. 4(c)).

After time t1, the output signal of the preheating timer circuit 8 becomes "L", and the inter-pulse preheating timer circuit 11, pulse generation time timer 12, and pulse generation signal circuit 9 each start operating. As shown in FIG. 4(f), the output signal of the power synchronization signal detection circuit 7 is divided into frequencies.First, the pulse generation time timer circuit 12 calculates the time required for pulse generation (time 17 in FIG. 4(d)). Outputs a “H” signal until

The preheating timer circuit 8 becomes L'' at time t1, and at this time, the inter-pulse preheating timer circuit 12 and the capacitor 111 input pulses, so that each counter 101 r103, 105 of the pulse generation phase setting circuit 10 starts the basic oscillation. Counting starts with the clock (for example, 10 KHz) of the circuit 14, and (t2-tt), (
t5-t4) and (ta-tt) waveforms are output. At this time, shift registers 91 and 92 of the pulse generation signal circuit 9
．． 93, the (ti-tt
) waveform is output.

Each signal is synthesized by the main switch operation signal circuit 13,
As shown in Fig. 4 (g), at the current rise time D+)
The "L" signal is output after (tz-tt) time.

As a result, the main switch element 5 is cut off as shown in Fig. 4 (11), cutting off the preheating current ■, and a pulse voltage is generated as shown in Fig. 4 (i) due to the transient phenomenon of the ballast element 3. .

After this, the main switch element 5 switches between the pulse preheating timer circuit 1
The continuous state is maintained until the output of No. 1 becomes H'' (No. 4
(13:00 in figure (f)). Now, at time t11, the inter-pulse preheating timer circuit 11 becomes H'' due to the pulse of the power synchronization signal detection circuit 7, and the main switch operation signal circuit 13
The main switch element 10 is turned on and preheats the filaments 4a and 4b of the discharge lamp 4.After that, when the above-mentioned pulse is applied at 1 o'clock, the pulse generation signal circuit 9 turns on the shift lamp. 2nd due to 91,92.93
Output the second waveform. Each signal is synthesized by the main switch operation signal circuit 13, and as shown in FIG. A voltage is generated.The operation is repeated in the same manner, and a pulse is generated at 8 o'clock.

At this time, the output signal of the pulse generation signal circuit 9 is as shown in FIG.
As shown in the waveform of the preheating current I shown in ), the interrupting current is gradually increased by counters 101, 103, and 105. Now, by generating a pulse at time t8, the discharge lamp 4 is lit, the output signal of the main switch operation signal circuit 13 is maintained at L'', and the discharge lamp 4 is maintained lit.

As described above, in this embodiment, after preliminary preheating, at the rise of the preheating current I (at 2 o'clock in the diagram f54), the main switch element 5 is cut off to cut off the current ■, and a pulse is generated. , In the next cycle (time t1 in FIG. 4), the main switch element 5 is turned on to preheat the filaments 4a and 4b of the discharge lamp 4. Thereafter, this operation is repeated, pulse generation and preheating are performed alternately every cycle, and the pulse voltage is increased sequentially from the low voltage pulse to the high voltage pulse. Here, the timers 82, 122 and counters 101, 103, 105 in FIG. 3 may be any timer circuits having clock and clear functions, such as a timer IC such as a monostable multivibrator or μPC4020 (manufactured by NEC Corporation). Also latch circuit 81°12
1.102, 104, 106, frequency dividing circuit 110, and shift renostars 91, 92, 93 are each shown using 7-lip 70-tub units such as μpc4013 (manufactured by NEC Corporation).
Any type of material may be used as long as it performs the above operations.

E1 Eclipse 2 Another embodiment is shown in FIG. 5, and its operating waveforms are shown in FIG. 6. Since the basic operation is the same as that of the circuit of the first embodiment shown in FIG.

In this embodiment, the inter-pulse preheating timer circuit 11 is
Using the timer circuit 112 and latch circuit 113 instead of the frequency dividing circuit shown in the figure, the main switch operation signal circuit 13 operates from time t2 when the output of the main switch operation signal circuit 13 becomes "L" as shown in FIG. 6(f). What about the point that the "H" signal is output at certain times? 8
have symptoms.

According to this operation, the main switch element 5, which was once cut off, becomes conductive again at time 1 within the same period, and a preheating current I is applied to the filaments 4a and 4b of the discharge lamp 4, as shown in FIG. 6(h). Then, the main switch element 5 repeats the interruption and conduction within the same period.

After the preliminary preheating, at the rise of the preheating current (time t2 in Fig. 6), the main switch element 5 is turned off to cut off the electric current and generate a pulse. 3
At the time, α) turns on the main switch element 5 and filament) 4a
, 4b. Thereafter, this operation is repeated to sequentially repeat pulse generation and preheating within one cycle, and the pulse voltage is increased sequentially from the low voltage pulse to the high voltage pulse. In this embodiment, since pulse generation and preheating are performed in every cycle, earlier start-up is possible than in the first embodiment.

Note that FIGS. 6(a) to (i) correspond to FIGS. 4(a) to (i).

[Effects of the Invention] The present invention provides a ballast element including an inductance inserted in series between a preheating discharge lamp and an AC power supply, and a main switch element connected in parallel between the non-power supply side terminals of the discharge lamp. and,
It consists of a control circuit that is connected in parallel to the main switch element and controls the main switch element, and sets a preheating advance period in which the main switch element is conductive for a certain period of time after the power is turned on, and a point at which the preheating current rises after the preheating advance period has elapsed. Since the main switch element is shut off and pulses are generated at both ends of the discharge lamp, the interrupted WI current can be stabilized, and the generated pulse voltage is therefore stabilized, making it possible to apply the designed pulse voltage to the discharge lamp. This makes it possible to extend the life of the discharge lamp and improve the M conformity. Furthermore, since the pulse generation period and the period in which the main switch element is made conductive and the preheating current flows through the discharge lamp are alternated, the discharge lamp can be heated by preheating. The effect is that the starting point can be brought forward, and since the cut-off phase of the main switch element is gradually increased, the cut-off current value can be increased, and the pulse voltage can be increased sequentially from low voltage to high voltage. It can be used for discharge lamps ranging from low wattage to high wattage, with different optimum starting pulse voltages, and the optimum pulse can be gradually applied to discharge lamps in response to changes in ambient temperature, ballast elements, and variations in discharge lamps. This has the effect of further extending the life of the discharge lamp.

[Brief explanation of drawings]

FIGS. 1(a) and (b) are the basic circuit configuration diagram of the present invention and the configuration diagram of the main switch element, and FIG. 2 is a circuit diagram of the control circuit according to the embodiment of the present invention. 3 is a specific circuit diagram of the control circuit same as the above, FIG. 4 is a waveform diagram for explaining the operation of the same, FIG. 5 is a specific circuit diagram of the control circuit of the second embodiment of the present invention, and FIG. 6 is the operation of the same as the above. Explanatory waveform diagram, Figure 7 (
a) and (b) are basic circuit configuration diagrams and main switch element configuration diagrams of the conventional example, FIG. 8 is a waveform diagram for explaining the operation of the same as above, and FIG. 9 is a waveform diagram for explaining the operation of another conventional example. In the waveform diagram, 1 is an AC power supply, 3 is a stable element, 4 is a discharge lamp, 5 is a main switch element, 6 is a control circuit, and 2 is a preheating current. Agent Patent Attorney Ishi 1) Chief Figure 7 4

Claims (3)

[Claims] (1) A ballast element including an inductance inserted in series between a preheating discharge lamp and an AC power supply, a main switch element connected in parallel between the non-power supply side terminals of the discharge lamp, and the main switch. It consists of a control circuit that is connected in parallel to the element and controls the main switch element, and the control circuit sets a preheating period in which the main switch element is conductive for a certain period of time after the power is turned on, and also controls the rise of the preheating current after the preheating period has elapsed. At this point, a period in which the main switch element is cut off to generate a pulse at both ends of the discharge lamp and a period in which the main switch element is made conductive to cause a preheating current to flow through the discharge lamp are set alternately, and a phase in which the main switch element is cut off is set alternately. A discharge lamp starting device characterized in that the device is set to gradually increase in size. (2) After the main switch element is turned off at the rise of the preheating current, the cutoff state is maintained until the next cycle of the AC power supply, and a period is set in which the main switch element is made conductive and the preheating current flows in the next cycle. A discharge lamp starting device according to claim 1, characterized in that: (3) A period is set in which the main switch element is cut off at the rise of the preheating current, and then the main switch element is made conductive within the same cycle to flow the preheating current. Electric light starter.