JPH02192696A - Discharge lamp lighting device - Google Patents

Abstract

PURPOSE:To prevent heating and deterioration of a switching element even though the resonant frequency of a resonance circuit is varied, by detecting the resonant condition of the resonance circuit, and at the same time, regulating the OFF period of the switching element responding to the resonant frequency of the detected resonant condition. CONSTITUTION:A resonance circuit to which the power is fed by a DC power source 63, a switching element 69 to set the resonance circuit at a resonant condition, and a control device which detects the resonant condition of the resonance circuit and outputs a synchronous signal to the single stable multivibrator of an oscillation circuit 65 depending on the detection are provided. As a result, the ON period of the switching element 69 is quickened when the resonant frequency is high, while the ON period of the switching element 69 is delayed when it is low, and the OFF period of the switching element 69 is regulated. Consequently, the switching element 69 is turned on at the time when the resonant wave form of the resonance circuit is attenuated sufficiently, and the switching element 69 is prevented from receiving a steep current.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a so-called resonant inverter-type discharge lamp lighting device for lighting a discharge lamp such as a fluorescent lamp at high frequency using an inverter device. 〉 In conventional discharge lamp lighting devices, an LC resonance type inverter device is used in order to reduce switching loss due to the high frequency of the inverter device equipped with transistors, and the oscillation that is the drive source of the inverter device is used. The circuit includes LC
An astable multivibrator that is asynchronous to the resonance part is used.

FIG. 9 shows a circuit diagram of this type of asynchronous inverter device (Japanese Patent Application Laid-Open No. 60-189897 [1105841
/24]). In this equipment, commercial power supply (60〉
A full wave rectifier (61) is connected to the full wave rectifier (61).
Connect a capacitor (62) between the outputs of the DC power supply (
63), an oscillation lance (74), a switching element 7' consisting of a transistor (69), a resonant capacitor (70), a damper diode (71),
Both discharge lamps (72)! 4 (72a) (721J
), a preheating ballast element (73) connected to a resistor (6G
) <68), capacitor (67), discharge rung (72
) and an oscillation circuit (65) consisting of a choke coil (75) for improving the current waveform and an astable multivibrator.
).

Does the oscillation circuit (65) not operate when the DC power supplies (63) and (64) are turned on? The oscillation circuit (65) outputs a "Hi" signal for a predetermined period A as shown in 10th [21(a)].
゛, During the predetermined period B, a signal that becomes "'Lo"' is output.

As shown in FIG. 10(b), in period A, the base current Ih flows from the oscillation circuit (65) through the capacitor (6) and the resistor (66) to the base of the switching element (69), and in period B, the base current 1b is inverted.

The base current 1b causes the switching element (69) to
is turned on and off to perform inverter operation, as shown in Figure 10 (
The base current 1b is applied to the switching element (69) as shown in e).
During the period A in which is flowing, the switching element (69
) is turned on and the collector current 11C flows, and when the base current 11i is reversed, the switching element (
69) is turned off, the collector current Ic is cut off during period B, and the collector voltage Vce is the oscillating transformer (74).
and a resonant waveform with a resonant frequency determined by the resonant capacitor <70). As a result, the damper diode (7
A damper current 1d flows through 1).

(Problem to be Solved) Here, as shown in FIG. 10(c), the switching cable (69
) In order to change the collector current Ic and collector voltage Vce of the oscillation circuit (65) at the desired timing from the viewpoint of efficiency, it is necessary to It is necessary to adjust the oscillation frequency in advance, but if the adjustment is incorrect or if there is a load fluctuation on the discharge lamp (72), the above-mentioned resonance waveform will collapse and loss of the switching cord (69) will occur. There is a problem that becomes very large.

In particular, in a discharge lamp lighting device, the discharge lamp (72) reaches normal lighting through the process of preheating and starting the two ridges (72a) (72b), so the load condition differs between starting and normal lighting. The resonant frequencies of the resonant circuits are different.

For example, in the circuit shown in Figure (:), when the discharge lamp (72) is normally lit, the collector voltage Vce of the switching cable (69) is completely il! as shown in TollJ (c).
Even if the oscillation frequency of the oscillation circuit (65) is selected so that the switching element (69) turns on at the moment when the discharge lamp (72) is turned on normally, both b (72a)
) (72b> During preheating, in addition to the inductance of the oscillation transformer (74) and the capacitance of the resonant capacitor (70), the capacitance of the preheating ballast element (73) contributes to the time constant, increasing the resonance frequency. become.

Switching element resistance when the resonant frequency increases69)
The waveforms of collector current Ic and collector voltage Vee are shown in FIG. 10 (, I). As is clear from the figure,
Since the off period of the switching element (69) is constant, as the resonant frequency of the collector voltage Vce increases, the period during which current flows through the damper diode (71) becomes longer. In addition, the peak value I2 of the collector current is as shown in Fig. 10 (
This is excessive compared to the peak value 11 of the collector current Ic during normal lighting of the discharge rung shown in c). As a result, the temperature of the damper diode 1ζ (71) and the switching element (69) increases rapidly, leading to deterioration of the element Y and deterioration of efficiency.

Also, due to temperature characteristics etc., the resonance frequency may change as shown in Fig. 10(d).
When the voltage rises further from the current level, the switching element (69) turns on at the rising edge of the resonant voltage of the collector voltage Vce at the time of transition to the second period A/\, as shown in 10th IJ(e). As a result, a steep collector current Ic flows, and there is a possibility that the switching element (69) may be thermally destroyed.

The waveforms at the 10th ports (d) and (e) show the drawbacks when preheating the poles (72a) and (72b) of the discharge lamp (72).
Even during normal lighting, the switching element <69) is
Even if it operates as shown in Fig. 10(c) for the first period, the inductance of the 5-C transformer (74) increases due to the temperature rise of the oscillation transformer (74) after operation, and the resonant capacitor (70 ) may lower the resonant frequency of the resonant circuit. As a result, as shown in FIG. 10(f), when the switching element (69) is turned on, the collector current l is steep.
c will flow.

Furthermore, when an astable multivibrator that is asynchronous with the LC resonance part is adopted as the oscillation circuit (65), the circuit type,
There is a problem in which it is difficult to determine +t. For example, when trying to improve the lighting start characteristics of a discharge lamp, the circuit constants cannot be selected easily, and as a result, it becomes necessary to remove a conductor near the discharge lamp on the lighting equipment side, and the lighting This imposes constraints on the design of the equipment.

An object of the present invention is to provide a discharge lamp lighting device that can prevent heating, deterioration, and destruction of switching elements even if the resonant frequency of a resonant circuit changes when starting and lighting a discharge lamp.

(Means for solving the problem) A first discharge lamp lighting device according to the present invention has a DC power source (63
) (64), a resonant circuit powered by the DC power source, a switching cable (69) for setting the resonant circuit to a resonant state, and a discharge lamp (64) interposed in the resonant circuit.
72), an oscillation circuit (65) consisting of a monostable multivibrator that turns on and off the switching element, and a monostable multivibrator of the oscillation circuit (65) that detects the resonance state of the resonance circuit and based on the detection. and control means for issuing a synchronization signal to.

Further, the second discharge lamp lighting device according to the present invention uses a DC power source (
63) and a resonant circuit powered by the DC power source;
a switching element (6) that sets the resonant circuit to a resonant state;
9) and a discharge lamp (72) interposed in the resonant circuit.
, an oscillation circuit (65) consisting of a monostable multivibrator that turns on and off the switching element, and a resonant voltage of the resonant circuit is detected, and based on the detected voltage, whether the discharge lamp (72) is in a normal lighting state or not. , and a detection circuit that detects whether the oscillation circuit is in the starting state, and the pulse width of the output pulse of the oscillation circuit is switched according to each of the normal lighting state and the starting state detected by the detection circuit! 1. It is assumed to be an i symptom.

((Yakawa) In the first discharge lamp lighting device, the control means
The resonant state of the resonant circuit that occurs when the switching cable (69) is off is detected, and based on the detection, the field sound with a high resonance frequency advances the on timing of the switching element, and the field sound with a low resonance frequency advances the on timing of the switching element. delays the on-time of the switching cable and adjusts the off-time of the switching element. As a result, when the resonant waveform of the resonant circuit is sufficiently attenuated, the switching element is turned on, and a steep current is prevented from flowing through the switching cable.

Further, in the second discharge lamp lighting device, the pulse width of the output pulse of the oscillation circuit when the starting state is detected by the detection circuit is set smaller than that when the normal lighting state is detected. be done. As a result, in the starting state, the period during which the switching element (43) is on is shortened compared to the normal lighting state, and excessive current is prevented from flowing during starting.

<Effects of the Invention> According to the discharge lamp lighting device according to the present invention, a steep current does not flow through the switching element at the time of starting and lighting the discharge lamp, regardless of fluctuations in the resonant frequency of the resonant circuit.
Heat generation, deterioration, and destruction of switching elements can be prevented.

(Examples) The examples are for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing its scope.

First, based on FIGS. 1 to 3, the first
The basic configuration of the discharge lamp lighting device will be described below.

In this device, as shown in Fig. 1, an oscillation transformer (74)
The output end of the secondary winding (74b) is connected to the detection phase control circuit (
76) and the trigger circuit (77), the oscillation circuit (
The phase of the oscillation circuit (65) is controlled by feeding back to the monostable multivibrator (e5). The detection phase control circuit (76) controls the oscillation transformer (74) based on the voltage waveform of the secondary winding (74b) of the oscillation transformer (74).
), resonant capacitor (70) and preheating ballast element (7
3) detects the resonant state of the resonant circuit formed by 3), and generates a phase control signal based on the detection signal. Further, the trigger circuit (7)) generates a monostable Maruna vibrator l\trigger signal of the oscillation circuit (65) based on the phase control signal.

In the above device, as shown in FIG. 2(f), when a signal of I (i'' is output from the terminal of the oscillation circuit (65) for a predetermined period A, the capacitor (67) and the resistor (66) Then, the base current 1b shown in FIG. 2 ([I) flows through the switching element (69), the switching element (69) is turned on, and the collector current 1c shown in FIG. 2 (,) flows.

After that, the period A has passed, and the terminal 11 of the oscillation circuit (65)
When the output signal of is in the °'Lo" state, the switching element (69) is turned off and the collector current 1c is cut off. As a result, the oscillation transformer (F4) and the resonant capacitor (
70), and the collector voltage Vce of the switching element (69) changes as shown in FIG. 2(a). This resonance is caused by the secondary winding (74b) of the oscillating lance (74).
) induces a voltage waveform shown in FIG. 2(b).

The detection phase control circuit (76) detects the zero crossing of the voltage waveform shown in FIG. 2(b), shapes it into a square wave as shown in FIG. 2(C), and further shifts the phase of the square wave by a predetermined amount. As a result, the phase control signal shown in FIG. 3(d) is created.

The phase control signal is sent to a trigger circuit (77)/\, thereby creating a trigger signal in the second circuit (not shown in 1(e)). The rigger signal is input as a synchronization signal at terminal BJ of an oscillation circuit (65) composed of a monostable multivibrator, and as a result, the terminal BJ is
), an output signal that is used for a predetermined period A is generated.

FIG. 3(b) shows the output waveform from the terminal 1 of the oscillation circuit (65), and FIG. 3(e) shows the waveform of the base current Ib of the switching element (69).

Therefore, both poles (72aH72b) of the discharge lamp (72)
During preheating, oscillation [・Lance < 74) and resonance capacitor ()
Even if the preheating ballast element (73) is added to O) and the frequency of the resonant circuit increases, the turning-on point of the switching element (69) is controlled according to the resonant state.
As shown in 4-4, the collector current Ic, collector voltage Vce, and damper diode (
71) damper current 1tl has a good operating waveform.

It goes without saying that even if the common frequency of the resonant circuit fluctuates for some reason other than during preheating, the same effect as described in 111f can be obtained.

Next, specific embodiments of the first and second discharge lamp lighting devices according to the present invention will be described based on FIGS. 1 to 8.

As shown in Fig. 11, the discharge lamp lighting device consists of a DC power source 1, a resonant circuit 2 supplied with power by the DC power source 1, an oscillation circuit 2 composed of a monostable multivibrator), and the oscillation circuit 1. A starting circuit (2) for starting, a switching element (43) that is turned on and off by an output signal from the oscillation circuit to cause the resonant circuit to resonate, a discharge lamp (51) interposed in the resonant circuit, and a switching element (43) for supplying power to the oscillation circuit. By detecting the DC power supply ■ and the resonant voltage of the resonant circuit from the secondary winding (46b) of the oscillating lance (46), it can be determined whether the discharge lamp (51) is in a normal lighting state or not.
(5ta) (511)) is in the preheating state, and switches the ``'II period'' of the output signal of the oscillation circuit to an appropriate time. In order to specify the timing of outputting the signal, a detection phase control circuit (2) detects the resonant state of the resonant circuit from the secondary winding (46b) of the oscillation transformer (46) and converts the phase; A trigger circuit (2) converts the phase control signal into a trigger signal for the oscillation circuit.

The DC power source l includes a commercial power source (1) and a commercial power source (1).
) and a smoothing capacitor (3). In addition, the inverter device that should be operated with a 3μ DC power source is a 1U lamp (5μ
1), an oscillation transformer (46), a switching element (43) consisting of a transistor, and a resonant capacitor (44).
) of a discharge lamp (51) consisting of a filament (51a) (51
The capacitor (50) installed between 1+) works for preheating and starting the lighting, and the choke coil (49) works for the discharge lamp (
51) This is provided for the purpose of improving the lamp current waveform during lighting. A damper diode (45) is connected to one end of the emitter of the switching element (43).

The oscillation circuit 26 III includes a timer integrated circuit (26) (for example, μPCl555C manufactured by NEC Corporation) used as a monostable multivibrator and a resistor (17) (23
) (52) and a capacitor <18), and the resistors (40) (42) and the capacitor (41) are
High switching speed of f-sonang element T (43) 1
This is designed to serve as the main LI.

The DC power supply ■ for the oscillation circuit is the oscillation [・lance (46)
A diode (47) and a resistor (
48), capacitor (6), Zener diode (5)
, and a resistor (4). The resistor (4) also serves to feed the oscillation circuit I['\ when the commercial power supply (1) is turned on.

The dynamic circuit ■ is an integrated circuit for system reset (10
) (for example, PST520 manufactured by Mitsumi Electric Co., Ltd.), resistors (7) (8), capacitors (9) (21) (22), and diodes (19) (20).

The Hi period conversion circuit ■ consists of resistors (11) (12) (15
) (16), consisting of a transistor (13), a Zener diode (14), and a capacitor (24), and converts the induced voltage in the secondary winding (46b) of the oscillation transformer (46) to a diode (47) and a capacitor (24). The DC voltage rectified and smoothed is divided by the resistors (15) and (16), and the Zener diode (1
4) and l. By conducting and cutting off the transistor (13), the resistor (11)/
The integrated circuit for the timer (26) turns the current on and off.
It controls the voltage of the terminal ■.

In general, when the timer integrated circuit (26) is used as a monostable multivibrator, the "Hi" output terminal
The ° period is determined by the time constant of the resistor (17) and capacitor <18) connected to the terminal ■■, and the voltage of the terminal ■. ”°Converting the period.

The detection phase control circuit 39 (2) detects the zero cross voltage of the secondary winding (46b) of the oscillation lance (46), thereby controlling the oscillation lance (46) and the resonance capacitor (46).
4) To detect debris formed by the discharge lamp (51) and the capacitor (50). oscillation[·
Lance (40) ++7) Primary 8 wire (4 (iu) and secondary winding 451. (46b) are switching elements -i' (43
) is ON and 1-, so that the transistor (37) is turned on by the induced voltage of the secondary winding (46b).
People's winding direction is determined by JJJ.

When the voltage at the connection between the secondary winding (401+) and the resistor (39) changes from negative to positive, the transistor (37) turns on, and the transistor (32) turns off. ) forms an integrating circuit with the resistor (35) and capacitor (34) connected to the collector of
When the transistor <37) turns on, the capacitor <34
) potential is capacitor +7 (34) and resistor (35) 0'
, + time constant. 6℃ is a capacitor (34)
and a transistor (
32) turns off later than the transistor (37) turns on. This phase control is achieved by superimposing the DC component of the DC power source (■) on the primary winding (46a) of the oscillation transformer (46), while the zero cross of the secondary winding (46b) from negative to positive l\ This is done to correct the fact that the points are advanced in phase.

In addition, the detection phase system (the wholesale circuit ■ has a voltage dividing resistor (30) (3
1) is provided, and a diode (38) is provided for reverse breakdown voltage protection between the base and emitter of the transistor (37).
is equipped (jll).

Figure 7 (6), Figure 8 (b) (i > (j) (k) (1)
(product) is roughly the collector current Ic and collector voltage Vce of the switching element (43), the secondary winding voltage of the oscillation transformer (46), the base voltage of the transistor (37), [
・Collector voltage of the resistor (37), capacitor (3)
4) The voltage across the terminals, the base voltage of the transistor <32),
The waveform of the collector voltage of the L transistor (32) is shown.

The trigger circuit (2) forms a differentiating circuit by a capacitor (29) and a resistor (27) connected between the base and emitter of the L transistor (25).

Figure 8 (cormorant) (n) and (d) are respectively [・Langister (3)
2), the base voltage of the transistor (25), and the voltage waveforms at the terminal j'--(2) of the timer integrated circuit (26) connected to the collector of the transistor (25).

As shown in Fig. 5, in the timer circuit (26), when the voltage is applied to the voltage terminal j4 (Vcc) of the voltage terminal 11-('A), the terminal When applying a voltage of 17.72 or less of the terminal ~ (control voltage), that is, Vcc7'3 or less, the output voltage of the terminal (output) will be "
In this state, charging of the capacitor (18) through the resistor (17) is started.

When the potential of the capacitor (18) reaches the voltage of the terminal ■, the terminal ■ (threshold) turns “ON” and the terminal ■
is reversed to '1-70°'. At this time, capacitor (1
8) The charge charged in the terminal is discharged through the terminal ■ (discharge). Again, for terminal ■fi1. When a voltage of 2 or less is applied [J-, the same operation as described above is repeated. Here, the terminal r-■ (receiver/1) is connected to the same potential as the terminal ■.

Figures 7(b), (d), (e) and (r) show the voltage waveforms at terminals ■ and terminal ■■ of the integrated circuit for timer (26) and R3, terminal ■■, and terminal ■ in Figure 5. ing.

Hereinafter, the circuit operation 11 of the device shown in FIG. 4 will be explained.

Direct current immediately after turning on the commercial power supply (1)! The voltage waveform of 'X I and the voltage waveform of terminal (2) of the timer integrated circuit (26) transition to a steady state with a predetermined time constant, as shown in FIG. 7 (, Hb). Here, since the operation of the timer integrated circuit (26) is uncertain if the terminal ■ is below the guaranteed operation voltage, the timer integrated circuit (26) will not operate if the terminal ■ is below the guaranteed operation voltage. It is composed of When the voltage reaches the voltage level in operation 1, the timer integrated circuit (26) is started by the starting circuit (2). Specifically, the output terminal (2) of the system reset integrated circuit (10) is connected to the terminal (2) of the timer integrated circuit (26) via the diodes (19) and (20). In the system reset integrated circuit (10), when the terminal (2) becomes equal to or higher than the signal generation start voltage, the terminal (2) changes from 'Lo' to an open collector.

In the Figure 1 V) circuit, from the DC power supply I to the resistor (7
), and as shown in FIG.
10) end - r - ■, 7) (Start of occurrence of 3 - [The period C until reaching the voltage is longer than the time until the terminal ■ of the timer integrated circuit (26) reaches the guaranteed operation voltage. The time constants of the resistor (7) and capacitor (9) are selected. The resistor (8) is
It has the role of discharging the electric charge accumulated in the resistor (9) and dividing the voltage of the resistor (7).

During period C, no matter what voltage level terminal ■ of the timer integrated circuit (2G) has, terminal ■ is approximately zero, so the potential of resistor R3 in FIG. 5 also becomes zero, and terminal ■
The forward voltage drop due to the diodes (19) and (20) is approximately 1. , -IV, 'ls', 'r' child ■ to Z' remains ILOI+.

Thereafter, when the period C has passed, the timer integrated circuit i1'I
! The end -r■ of (26) is mainly R1 and R1 of FIG.
Since the voltage increases with the time constant of the capacitor (21) in Figure 1, when the potential of terminal ■ becomes lower than the potential of R3 of No. 512I, the output voltage of terminal j'-■ becomes Ili'', and the switching element (43) is turned on and inverter operation starts.

As shown in FIG. 7, the period during which the potential of the terminal *3 is lower than the potential of the terminal *3 shown in FIG. A time constant of is selected. A series of waveforms at each of these parts is as shown in No. 7 (4).

Next, the operation of the lli period conversion circuit (2) will be explained.

When the commercial power supply <1) is turned on and the discharge lamp (51) is in a state until it lights up, one filament of the discharge rung (51) is turned on from the DC power supply I during the ON period of the switching element (43).゛l・(51a), capacitor (50),
The other filament of the discharge lamp (51)!・(51b)
, oscillation) - a preheating current flows through the primary winding (46a) of the lance (46) and between the collector and emitter of the switching element (43). Also, Swift〉glue-r(4
3) During the off period, the inductor of the oscillating transformer (46), the resonant capacitor (44) and the capacitor (50
) is in operation during the starting process of the discharge lamp (51), its inductance is small, and the capacitor (50) does not affect the resonant frequency. In this case, when viewed from the oscillation lance (46), the resonant capacitor (44) and the capacitor (50) are connected in series, the α-acid diV yavasitance decreases, and the resonant frequency increases.

After the discharge valve (51) is turned on, the influence of the capacitor (50) is almost gone, and the resonant frequency in this case is the oscillation l.
Lance (46) - (> ductance and resonant capacitor (
44).

In addition, in the resonant circuit H, as the resonant frequency increases, the resonant current changes (-) and the resonant current increases, so the discharge lamp <51
), a voltage much higher than normal is generated in the secondary winding (46b) of the discharge lamp (51) until the discharge lamp (51) is turned on.

The DC voltage rectified by the diode (47) and capacitor 24) decreases from V to V2 from the time of starting to the time of lighting, as shown in No. 8 [;J (0)]. Different. This voltage is connected to resistor (15) and resistor (16)
When the starting voltage is v2, Zener diode 1 conducts (14) to turn on transistor (13), and when the lighting voltage is v2, Zener diode (14) is turned on. This means that the L transistor (1:3) is turned off.

When the transistor (13) is turned on, the terminal ■C\external resistor (11) of the timer integrated circuit (26) is connected, and the voltage at the terminal
2. It becomes the divided voltage between R3 and the resistor (11), and when the external resistor (11) is not present, the ratio!・The voltage decreases.

When the voltage at terminal -r-■ decreases, since the time constants of the ht resistor (17) and capacitor (18) connected to terminal -■■ are constant, the voltage output from terminal -■) is 1°
The period of ゛ becomes shorter. 6 nights, switching element 4
3) becomes shorter than the ON period, and the resonant frequency of the resonant circuit H increases when starting. , even if switching cables (43)
Excessive collector current does not flow during the ON period of
This prevents the switching element (43) from being destroyed. A series of waveforms at each of these parts is shown in FIGS. 7 and 8 in 4 ways, P.

In an L-number electric lamp lighting device, as in a discharge lamp, theoretically t (a rough discharge load is interposed in the resonant circuit, f''L
When load fluctuation occurs, switching Jt', 1'
Switch at the appropriate timing to maintain normal operation.
There are many things that happen. 1c-t, co-design circuit J) The degree of freedom in selecting constants is higher than b'C East.

In addition, by detecting the resonant voltage of the resonant circuit, it is possible to detect whether the discharge lamp is in a normal lighting state or in a starting state. Ili°°Switch the arrest period, normally lit ++;I
Since appropriate values have been set for both the normal lighting conditions and the 4° start, heat generation, poor performance, and destruction of the 1st jig material can be prevented.

Furthermore, by using lU <ii'fI of a simple configuration in Figure 1, the resonant circuit is detected as 1'2, and high vibration 115 (lower vibration and high efficiency are realized). 9 In addition, the drawings and Example 5 (G) describe the present invention.
Therefore, it should not be construed as limiting the invention described in the claims or reducing its scope.

In addition, the configuration of each part of the present invention is not limited to the description and examples, but is within the technical scope of the claims. Of course, modifications are possible.

[Brief explanation of the drawing]

112I is a discharge lamp lighting device according to the present invention), 2! A block showing the basic circuit configuration (7 block diagram, Figure 2 is 111F)
Figure 3 is a signal waveform diagram showing the operation of the circuit in Figure 1 when the discharge lamp is started; A specific example of a discharge lamp lighting device is shown.1. Fig. 5 is a block diagram of a timer integrated circuit, and Fig. 0 is a system denomination and reset integrated circuit. G value circuit diagram, Figure 7 and Figure 8113
4 represents the operation of the circuit shown in FIG.
is a signal waveform diagram showing the operation of the 07th circuit. (63)...DC power supply <65)...Oscillation circuit (74)...Oscillation l/Ransk 72)...Discharge lamp (76)...Detection phase control circuit'&8 (77)/Heat/Rigger times y8

Claims (1)

[Claims] [1] A DC power source (63), a resonant circuit supplied with power by the DC power source, a switching element (69) for setting the resonant circuit to a resonant state, and a switching element (69) interposed in the resonant circuit. A discharge lamp (72), an oscillation circuit (65) consisting of a monostable multivibrator that turns on and off the switching element, and a resonant state of the resonant circuit is detected, and switching is performed according to the resonant frequency of the detected resonant state. A discharge lamp lighting device comprising: control means for creating a synchronization signal for adjusting the off period of the element (69) and supplying it to the monostable multivibrator. [2] A DC power source (63), a resonant circuit powered by the DC power source, a switching element (69) for setting the resonant circuit to a resonant state, and a discharge lamp (72) interposed in the resonant circuit. , detecting a resonant voltage of an oscillation circuit (65) consisting of a monostable multivibrator that turns on and off the switching element and the resonant circuit, and based on the detected voltage, whether the discharge lamp (72) is in a normal lighting state; and a detection circuit that detects whether the oscillation circuit is in a starting state, and is characterized in that the pulse width of the output pulse of the oscillation circuit is switched depending on each of the normal lighting state and the starting state detected by the detection circuit. Discharge lamp lighting device.