JP3033782B2 - Discharge lamp lighting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp lighting apparatus in which a discharge lamp and another lamp such as an incandescent lamp can be turned on by one appliance.

[0002]

2. Description of the Related Art Conventionally, lighting equipment using a discharge lamp has been widely used. Generally, in order to light a discharge lamp,
A lighting device is required between the power supply and the discharge lamp as a stabilizing element for limiting the current supplied to the discharge lamp. This lighting device has a one-to-one correspondence with a combination of a power supply and a discharge lamp, and depends on a voltage and a frequency of the power supply, a wattage and a type of the discharge lamp (for example, a difference between a metal halide, a sodium lamp, and a mercury lamp). It is individually designed correspondingly. Therefore, if a different discharge lamp is connected to a lighting device designed for a certain power supply and discharge lamp combination,
Even if it is turned on, it does not emit light properly or becomes overloaded, causing problems such as breakage of the discharge lamp. Further, in such a discharge lamp lighting device, there is a problem that even if an incandescent lamp is turned on instead of the discharge lamp, sufficient light is not emitted, or a filament is broken due to an overload.

[0003] Discharge lamps also have a lifetime. Even if the discharge lamp becomes unlit due to its life or the like, there is a demand for using another lamp for the luminaire as soon as possible. Also,
It is also conceivable to turn on another lamp instead of the discharge lamp to change the emission color and change the lighting effect. Most general lamps have a screw-type Edison base socket defined by the standard, and have the same shape for both discharge lamps and incandescent lamps. In addition, if the discharge lamp socket is configured in the same socket type as the halogen bulb (incandescent lamp) of the H4 bulb, which is widely used in automotive headlights, the same lamp body as the discharge lamp type headlight can be used. Can be attached.

[0004]

As described above, even if it is desired to replace a discharge lamp with another socket which has the same standard and which can be attached to the same lighting equipment, the lighting device of the discharge lamp has a power supply. And other sockets could not be easily used because of the presence between the lamp and the socket.

The present invention has been made in view of the above points, and an object of the present invention is to provide a discharge lamp lighting device, such as an incandescent lamp having a socket part of the same standard as the discharge lamp. Another object of the present invention is to enable a lamp to be almost normally lit.

[0006]

In order to solve the above-mentioned problems, in a discharge lamp lighting device according to the present invention, as shown in FIG. 1, a first lighting means 1 for lighting a discharge lamp comprises:
Second lighting means 2 for lighting a lamp other than the discharge lamp
And a lamp discriminating means 3 for discriminating the type of the lamp RL by applying a predetermined low voltage to the lamp RL and detecting the presence or absence of a lamp current before performing the operation of lighting the discharge lamp.
If the discharge lamp is suitable in accordance with the result of the determination by the lamp determining means 3, the first lighting means 1 is used to turn on the discharge lamp. Is provided with switching means Ry ₁ and Ry ₂ for turning on.

[0007]

The operation of the present invention will be described below with reference to FIG. When the power switch SW is turned on, supplies power to the lamp RL from the power source V ₁ through the first lighting means 1 for discharge lamp lighting, to determine the type of lamp RL by the lamp determination unit 3. If the type of the lamp RL is not suitable for the first lighting means 1, it is switched to the second lighting means 2 and
The lamp RL is turned on. Note that the first lighting means 1 and the second lighting means 2 may be shared by changing a part of the operation of the same lighting circuit according to the result of the determination by the lamp determining means 3. Instead of the lamp discriminating means 3, the characteristics of the lighting device may be changed after a certain period of time after the power is turned on, so that the other lamps can be rated to be lit.

[0008]

FIG. 2 is a circuit diagram of a first embodiment of the present invention. The power supply V ₁ is a DC power supply consisting of a battery, such as DC12V. Circuit A is a boost chopper circuit, and DC
The low-voltage power supply voltage of several tens of volts is boosted to a high voltage of Vdc = several hundred volts required to keep the discharge lamp lit. Circuit B
Is a full-bridge type rectangular wave inverter circuit, which supplies a low frequency rectangular wave voltage to the discharge lamp.

First, the configuration and operation of the circuit A will be described. DC power supply V ₁ is connected to power switch SW and relay contact R
through y ₁ is inputted to the chopper circuit A, the voltage is applied to the series circuit of the inductor L ₁ and the transistor Q _3. At both ends of the transistor Q ₃ are capacitor C ₁ for smoothing is connected via the diode D ₁ of the reverse-current blocking. When the power is turned on, the control circuit 4 starts to operate, the transistor Q ₃ is a high-frequency manner ON / OFF. ON the transistor Q ₃ Then, a current flows from the power source to the inductor L _1, the electromagnetic energy is accumulated.
The inductor L ₁ transistor Q ₃ is a turned OFF, the electromagnetic energy accumulated in inductor L ₁
It is across induced voltage of which is superimposed a supply voltage, the capacitor C ₁ for smoothing is charged through the diode D _1. Incidentally, the DC voltage Vdc obtained at the capacitor C ₁ for smoothing is fed back to the control circuit 4, it is adjusted to an appropriate voltage by controlling the switching frequency and the ON duty of the transistor Q _3.

Next, the configuration and operation of the circuit B will be described. DC voltage V charged in smoothing capacitor C ₁
dc is applied to a series circuit of the transistors Q ₄ and Q _{5 and} a series circuit of the transistors Q ₆ and Q ₇ . Diodes are connected in antiparallel to the transistors Q ₄ , Q ₅ , Q ₆ , and Q ₇ , respectively. Between the transistors Q _4, Q ₅ of the connection point and the connection point of the transistors Q _6, Q ₇ is a series circuit of a capacitor C ₂ and the inductor L ₂ is connected. The both ends of the capacitor C _2, the relay contact Ry _2, R
Lamp RL through y ₃ and lamp current detection circuit IDT is connected. The inverter control circuit 5 switches the transistors Q ₄ , Q ₅ , Q ₆ , and Q ₇ so that a low-frequency rectangular wave output is obtained from the inverter circuit B.

First, in the first period, the transistor
Q_Four, Q₇Is turned on / off synchronously with high frequency,
Transistor Q_Five, Q₆Is set to OFF. Transistor
Q_Four, Q₇Is turned on, the transformer is activated by the DC voltage Vdc.
Jista Q_Four, Capacitor C_TwoAnd lamp RL, inductor
L_Two, Transistor Q₇Current flows through the
Star Q _Four, Q₇Is turned off, the inductor L_Two,Tiger
Transistor Q₆Anti-parallel diode, capacitor C₁ ,
Transistor Q_Five Anti-parallel diode, capacitor C_TwoWhen
Current flows through the lamp RL. The high frequency component of this current
Minute is capacitor C_TwoThe lamp is bypassed by
A direct current flows in the RL in one direction.

Next, in the second period, the transistors Q ₄ and Q ₇ are turned off, and the transistors Q ₅ and Q ₆ are turned on / off in synchronization with high frequency. Transistor Q
_5, Q ₆ is turned ON, the transistor Q ₆ by the DC voltage Vdc, the inductor L _2, a capacitor C ₂ and the lamp R
L, a current flows through the transistor Q _5, the transistors Q _5, Q ₆ is turned OFF, the inductor L _2, a capacitor C ₂ and the lamp RL, the antiparallel diode of the transistor Q _4, the capacitor C _1, the inverse of the transistor Q ₇ Current flows through the parallel diode. Since the high frequency component of the current is bypassed by the capacitor C _2, the ramp R
A direct current flows through L in the opposite direction. Therefore, a low-frequency rectangular wave current whose polarity alternates between the first period and the second period is supplied to the lamp RL.

The current I flowing through the lamp RL is detected by a lamp current detection circuit IDT. This circuit IDT is:
It is configured to detect the presence or absence of a current I flowing through the lamp RL, and to output a High-level signal when the current I flows, and this signal is used as one input of an AND circuit AND. The other input of the AND circuit AND:
The output signal of the monostable multivibrator MMV is input. The trigger input of the monostable multivibrator MMV is connected to the DC power supply V ₁ through a power switch SW. When the trigger input rises to a high level, the monostable multivibrator MMV outputs a pulse having a constant width. This output signal, via a resistor R ₁ is also input to the base of the transistor Q _1, the transistor Q ₁ is to clamp the output of the control circuit 4 is connected between the base and emitter of the transistor Q ₃ ing.

TFF is a flip-flop, which is reset when the power is turned on, holds its output Q at a high level when its output Q goes to a low level and its clock input goes to a high level. The clock input of the flip-flop TFF is connected to the output of the AND circuit AND, the output Q of the flip-flop TFF is connected to the base of the transistor Q ₂ through a resistor R _2. The series circuit of the transistor Q ₂ and the relay coil Ry constitute a closed circuit with the series circuit of the DC power supply V ₁ and the power switch SW.

Ry ₁ , Ry ₂ , and Ry ₃ are contacts of the relay coil Ry and have a normally closed contact NC and a normally open contact NO, respectively. When the relay coil Ry is not energized, the relay contact Ry _1, Ry _2, Ry ₃ is connected to the normally closed contact NC, the relay coil Ry is energized, the relay contact Ry _1, Ry _2, Ry ₃ Is normally open contact N
Connected to O.

The operation of the circuit shown in FIG. 2 will be described below.
I do. When the power switch SW is turned on, the monostable multibar
The output of the vibrator MMV becomes High level,
Transistor Q₁ Is turned on, so that the chopper circuit A
Switching transistor Q _ThreeBetween base and emitter
Short-circuited. Therefore, chopper circuit A does not operate,
Densa C₁DC voltage Vdc is₁Equivalent to
It becomes about several tens of volts. The inverter circuit B has a low frequency
Is performed.

Here, if the lamp RL is a discharge lamp, the output voltage of the inverter circuit B is low, so that the discharge lamp cannot start discharging. Therefore, the lamp current I becomes zero, and the output of the lamp current detection circuit IDT becomes Low level.
Therefore, the output of the AND circuit AND is at the low level, and the output of the flip-flop TFF maintains the low level. Since the transistor Q ₂ is not turned ON, the relay coil Ry is not energized, the relay contacts Ry _1, Ry _2,
Ry ₃ remains connected to the normally closed contact NC side.

After the monostable multivibrator MMV generates a pulse (substantially several tens of microseconds to several seconds) for a predetermined time, the output goes low. After that, the monostable multivibrator MMV maintains the output at the Low level. Therefore, the output of the AND circuit AND remains at the Low level, and the output Q of the flip-flop TFF is also Low.
It remains at the w level. Therefore, the relay coil Ry
Is not energized, the relay contacts Ry _1, Ry _2, Ry ₃ remains connected to the normally-closed contact point NC side.

[0019] The output of the monostable multivibrator MMV becomes Low level, the transistor Q ₁ is turned OFF, the chopper circuit A starts operating. This allows
Since the voltage Vdc of the capacitor C ₁ reaches a predetermined high voltage, the output terminal of the inverter circuit B voltage for lighting the discharge lamp occurs, the discharge lamp lighting is started. The above operation is shown in FIG.

If the lamp RL is an incandescent lamp, a power supply
After turning on, the output of the monostable multivibrator MMV becomes Hi.
During the period of the gh level, the chopper circuit B has a low voltage.
Vdc is generated, but the lamp current I flows in the incandescent lamp
Therefore, the output of the lamp current detection circuit IDT is High level.
The output of the AND circuit AND is also at the high level,
The output Q of the flip-flop TFF becomes High level.
Transistor Q_TwoTurns ON and the relay coil Ry
Is excited and the relay contact Ry₁, Ry_Two, Ry _ThreeIs normally closed
All switches to the contact NO side, the lamp RL and the DC power supply V
₁ Is directly connected, the voltage V of the incandescent lamp increases, and the lamp is normally lit (=
Rated lighting) starts. After that, monostable multivibration
Even if the output of the data MMV goes low,
Since the output Q of the flop TFF cannot be inverted,
Keep the lighting state. The above operation is shown in FIG.

According to this embodiment, even fit discharge lamp to the lighting device, also, the discharge lamp having the same shape, there and in incandescent lamps can be lit with a DC power source V ₁ in the socket of the same standard However, any of them can be normally lit at each rated output. Note that a configuration may be adopted in which a commercial AC power supply is connected instead of the DC power supply V ₁ , and a rectifying smoother is added to the input side of the chopper circuit A.

FIG. 5 is a circuit diagram of a second embodiment of the present invention. AC commercial AC power supply, DB ₁ is a full-wave rectifier.
The output side of the full-wave rectifier DB ₁ is raised chopper circuit A
A step-down chopper circuit B ₁ and the low-frequency full-bridge circuit B
₂ is connected. First, the circuit A is a step-up chopper circuit similar to that of the first embodiment, and has an operation of generating a voltage Vdc for maintaining lighting of a discharge lamp and reducing input current distortion. Next, the circuit B ₁ is a step-down chopper circuit, and the control circuit 6 turns on / off the transistor Q ₈ in high frequency.
It was charged with a voltage V which is stepped down than the voltage Vdc to the smoothing capacitor C ₃ through the inductor L _3. The energy stored in the inductor L ₃ is refluxed through the diode D _2. By controlling the switching frequency and the ON duty of the transistor Q ₈ by the control circuit 6 controls the voltage V of the capacitor C _3, and controls the power supplied to the lamp. Furthermore, the circuit B ₂ is a low-frequency full-bridge circuit. Transistors Q _4, Q ₇ is ON, the first state in which the transistors Q _6, Q ₅ is OFF, the transistor Q _4, Q ₇ is OFF, the transistor Q _6, Q ₅
Is switched on at a low frequency (several hundred Hz). With these circuits B ₁ and B ₂ , a low-frequency rectangular wave voltage is obtained at the lamp RL.

Next, a configuration for controlling these circuits
Will be described. EA1 detects the lamp voltage V
Error amplifier for₁Is used to determine the target lamp voltage.
This is the reference voltage. EA2 detects the lamp current I
Error amplifier for _Two Is the target lamp current
Reference voltage for The error amplifier EA2 is
A low resistor for detecting the current I as a voltage signal.
The output of the error amplifier EA1 is a resistor R_FourAnd diode D_ThreeTo
Input to the PWM oscillator 8 through the error amplifier E
The output of A2 is a resistor R_FiveAnd diode D_FourThrough PWM
It is input to the oscillator 8. These diodes D_Three,
D_FourConstitutes a wired OR circuit. PWM oscillation
The device 8 is connected to the error amplifier EA1 or EA1 via a wired OR circuit.
Is a transistor Q according to the output of EA2.₈ON / OF
Perform F control.

Next, lamp current detection circuit IDT is made of a comparator CMP and a reference voltage E _3, the lamp current I
Comparator voltage of the low resistor R ₃ for detecting the C
With a reference voltage E ₃ by MP. This circuit IDT detects the presence or absence of a current I flowing through the lamp RL, and outputs a High-level signal if the current I is flowing. This signal is used as one input of an AND circuit AND. I have. The output signal of the monostable multivibrator MMV is input to the other input of the AND circuit AND. The trigger input of the monostable multivibrator MMV is connected to a control power supply.

The control power supply is a step-down transformer T connected to a commercial AC power supply AC via a power supply switch SW.
If, obtained a full-wave rectifier DB ₂ for rectifying the step-down output is constituted by the capacitor C ₄ for smoothing the rectified output, the power switch SW is turned ON, the DC voltage of the low voltage capacitor C ₄ Can be

When the trigger input rises to a high level, the monostable multivibrator MMV outputs a pulse having a constant width. This output signal is also input to the base of the transistor Q ₁ via the resistor R _1. The transistor Q ₁ is connected between the base and the emitter of the transistor Q ₃ to clamp the output of the chopper control circuit 4. Have been.

TFF is a flip-flop, which is reset when the power is turned on, holds its output Q at a high level when its output Q goes to a low level and its clock input goes to a high level. The clock input of the flip-flop TFF is connected to the output of the AND circuit AND, the inverted output and non-inverted output of the flip-flop TFF is connected to the bases of the transistors Q ₉ and Q _10. In each of the transistors Q ₉ and Q ₁₀ , the anode sides of the diodes D ₃ and D ₄ are connected to a ground line, respectively.

Hereinafter, the operation of this embodiment will be described.
When the power switch SW is turned on, a control power voltage is generated by the transformer T. As a result, the monostable multivibrator MMV is triggered, and its output Q is set to High.
Since the level, the transistor Q ₁ is turned ON, the step-up chopper circuit A becomes inoperative. Further, the step-down chopper circuit B ₁ and the low-frequency full bridge circuit B ₂ is operated. At this time, the non-inverted output Q of the flip-flop TFF
Low level and the inverted output is reset to the High level, the transistor Q ₉ is turned ON, the transistor Q
₁₀ is OFF.

Here, when the lamp RL is a discharge lamp, discharge does not start due to insufficient voltage across the lamp. Therefore, the lamp current I is zero and the lamp current detection circuit I
Since DT is at the low level, the output of the AND circuit AND is at the low level, and the flip-flop TFF is not triggered. When a predetermined time has elapsed and the output Q of the monostable multivibrator MMV goes to a low level, the output of the AND circuit AND is held at a low level. Therefore, the output of the flip-flop TFF is not changed, the transistor Q ₉ is ON, the transistor Q ₁₀ is OF
It becomes F. Therefore, the PWM amplifier 8 includes the error amplifier EA2
Is input. In addition, the transistor Q ₁ is OFF
As a result, the boost chopper circuit A starts operating, the discharge lamp is turned on, and the lamp current I flows. As a result, the output of the comparator CMP of the lamp current detection circuit IDT goes high, but the output Q of the monostable multivibrator MMV has already been low, so that the output of the AND circuit AND maintains the low level. Here, when setting the reference voltage E ₂ of the error amplifier EA2 to the lamp current value, the discharge lamp is normal lighting state. The above operation is shown in FIG.

If the lamp is an incandescent lamp, the output Q of the monostable multivibrator MMV becomes H immediately after the power is turned on.
The lamp current I starts to flow during the period of the high level,
Comparator CMP in lamp current detection circuit IDT
Is at a high level, and the output of the AND circuit AND is at a high level. As a result, the flip-flop TFF is triggered, and its non-inverted output Q becomes High.
Level, and the transistor Q ₁₀ is turned ON. Therefore,
The output of the error amplifier EA2 is not input to the PWM oscillator 8. On the other hand, the inverted output of the flip-flop TFF is Low.
Since the level, the transistor Q ₉ is turned OFF.
Therefore, the output of the error amplifier EA1 becomes the input of the PWM oscillator 8. Thereafter, when a predetermined time has elapsed and the output Q of the monostable multivibrator MMV becomes Low level, the operation of the boost chopper circuit A starts, and the lamp current I increases. When setting the reference voltage E ₁ of the error amplifier EA1 to the rated voltage value of the incandescent lamp, the incandescent lamp is a normal lighting state. The above operation is shown in FIG.

The second embodiment has the same effect as the first embodiment. In addition, in the first embodiment, the compensation for the fluctuation of the DC power supply V ₁ is limited to when the discharge lamp is turned on.
In a second embodiment, not only when the discharge lamp lighting only, even when an incandescent lamp lighting are possible compensation for variations of the DC power supply V _1. Therefore, the incandescent lamp can be used even if it is not for commercial power supply AC. For example, the incandescent lamp may be for 100 V, and the commercial power supply AC may be for 200 V. In the circuit shown in FIG. 5, the input of the error amplifier EA2 is the lamp current I, which is suitable for the constant current lighting of the metal halide lamp. However, if the input of the error amplifier EA2 is the lamp voltage V, the constant voltage of the sodium lamp is turned on. It is suitable for. In addition, commercial power supply AC
May be a DC power supply such as a battery of DC12V, this case can be omitted diode bridge DB _1.

FIG. 8 is a circuit diagram of a third embodiment of the present invention. The configuration is almost the same as that of the second embodiment. The detected value of the lamp voltage V and the detected value of the lamp current I are multiplied by a multiplier MLT, and the multiplication result is input to an error amplifier EA. The reference value of the error amplifier EA is a voltage Vx which depends on the reference voltage E ₁ and the resistor R _6, R _7, R ₈ and transistor Q _2.

The method of discriminating between a discharge lamp and an incandescent lamp is the same as in the second embodiment. If it is a discharge lamp, flip-flop TF
Inverted output of F becomes High level, thus, becomes the transistor Q ₂ is ON, the reference value of the error amplifier EA is Vx
= A _{R 7 · E 1 / (R} 6 + R 7). If incandescent lamp, the inverted output of the flip-flop TFF becomes Low level, therefore, the transistor Q ₂ is turned OFF, the reference value of the error amplifier EA is _{Vx = (R 7 + R 8} ) · E 1 /
_{(R 6 + R 7 + R} 8). Therefore, the reference value Vx of the error amplifier EA is higher in the incandescent lamp. In the third embodiment, since the lamp voltage V is multiplied by the lamp current I, the input of the error amplifier EA corresponds to the lamp power. In this embodiment,
Although the lamp is operated at a constant lamp power, a large amount of power is supplied to the incandescent lamp because the reference value Vx for the incandescent lamp is higher than that of the discharge lamp. In the case of the first or second embodiment, for example, 35
With a metal halide lamp of W, the light output is 2800
Im is obtained. To obtain the same light output with an incandescent lamp, a halogen lamp of about 110 W is required. In the present embodiment, if the lamp power output of the incandescent lamp is set to 110 W, the 110 W halogen lamp naturally has the same light output as the 35 W metal halide lamp, but the 55 W halogen lamp is forcibly operated at 110 W. The light output is equivalent. For this reason, there is a problem of shortening the life,
There is no problem in using the headlights of the vehicle for a short time until the vehicle arrives at the repair shop, and the headlights can be used without reducing the light output.

FIG. 9 is a circuit diagram of a fourth embodiment of the present invention.
You. V₁Is a DC power supply, and is provided through a power switch SW.
Switching element Q₁₁, Q₁₂Connected in series
You. Switching element Q₁₁, Q₁₂Is more than a MOSFET
Each has a built-in antiparallel diode. Switch
Ching element Q₁₂At both ends of the inductor L_FourAnd conden
Sa C_FiveThrough the capacitor C₆And lamp RL parallel circuit
Is connected. A resistor R is connected to both ends of the lamp RL.₉,
R_TenAre connected in parallel. Resistance R _TenBoth ends of
Is amplified by the amplifier circuit 11
Is done. Amplifier circuit 11 is operational amplifier OP and it is added
Resistance R₁₁, R₁₂, R₁₃, R₁₄, R ₁₅And Transis
TA Q₁₃, Q₁₄And reference voltage E_Four It has. Transi
Star Q₁₃, Q₁₄Is a power switch SW as shown in FIG.
Is turned off for a certain period of time from the time when
Both are turned on after the elapse. Transistor Q₁₃, Q₁₄Is O
The power of the operational amplifier OP when it is FF and when it is ON
FIG. 11 shows the relationship between the current Ix and the voltage V across the lamp RL.
You.

A triangular wave oscillator 10 is connected to the output side of the amplifier circuit 11. The oscillator 10 has a current mirror circuit including transistors Q ₁₅ and Q ₁₆ . Current Ic flowing through the transistor Q ₁₅ of the current mirror circuit, a current I of the current (Vcc / R ₁₆₎ to the amplifier circuit 11, which is determined with the power supply voltage Vcc for control resistor R ₁₆
It is a current obtained by adding x. Same current Ic flowing through the transistor Q ₁₅ is also flows through the transistor Q _16, to charge the capacitor C _7. When the voltage of the capacitor C ₇ exceeds the reference voltage E _5, Schmitt trigger circuit S
T output of becomes High level, the transistor Q ₁₇ is turned ON. Thus, the capacitor C ₇ is discharged. Thus, at both ends of the capacitor C ₇ sawtooth voltage Vc is generated. The sawtooth wave voltage Vc is compared with the reference voltage E ₆ of the comparator CP, is converted into a rectangular wave voltage of frequency f, is divided by the drive circuit 9, the input to the control terminal of the switching element Q _11, Q ₁₂ Is done. As a result, the switching elements Q ₁₁ and Q ₁₂ are alternately turned ON / OF.
F.

When the power switch SW is turned on, the timer 12 is started. The output of the timer 12 is at a low level when the power is turned on, and after a predetermined time T elapses, as shown in FIG. 10, goes to a high level. Timer 1
The output of 2 is input to the control terminals of the transistors Q ₁₃ and Q ₁₄ , and when the output of the timer 12 becomes High level, the transistors Q ₁₃ and Q ₁₄ are turned on. When the lamp voltage V is low, as shown in FIG. 11, when the transistors Q ₁₃ and Q ₁₄ are ON and OFF,
The magnitude of the current Ix of the operational amplifier OP differs. Thus, the size is changed in the current Ic flowing through the current mirror circuit, the charging rate of the capacitor C ₇ is changed, the oscillation frequency f of the oscillator 10 changes. Conversely, when the ramp voltage V is high, the output of the operational amplifier OP is saturated, so that the oscillation frequency f of the oscillator 10 does not change.

Now, switching is performed at the oscillation frequency f of the oscillator 10.
Ching element Q₁₁, Q₁₂Are turned ON / OFF alternately
Thus, high-frequency power is supplied to the lamp RL. Ma
Switching element Q₁₁Is ON and switching element Q
₁₂Is OFF, DC power supply V₁Power switch from
SW, switching element Q₁₁, Inductor L_Four, Conde
Sensor C_Five, Lamp RL and capacitor C₆The current through
Flows. Next, the switching element Q₁₁Is OFF and switch
Ching element Q₁₂Is ON, the capacitor C _FiveThe
As a source, a capacitor C_Five, Inductor L_Four,switch
Element Q₁₂, Lamp RL and capacitor C₆Through
The current flows. Note that the capacitor C_FiveIs for DC component cut
And the capacitor C₆And inductor
L_FourConstitutes an LC series resonance circuit. Due to resonance
The feedback current of the switching element Q ₁₁, Q₁₂Antiparallel
Flow through iod.

Here, when the lamp RL is a high pressure discharge lamp,
In this case, the activation operation will be described. Immediately after turning on the power
Indicates that the output of the timer 12 becomes
Jista Q₁₃, Q₁₄Becomes OFF. Therefore, FIG.
According to the characteristic shown, the voltage V across the lamp RL increases.
, The output of the amplifier circuit 11 decreases and the current Ix increases
Since the current Ic also increases, the oscillation frequency of the oscillator 10
f increases. As a result, immediately after the power is turned on, the lamp
The relationship between the current I and the lamp voltage V is shown in the characteristics of FIG.
Become like By the time the predetermined time T elapses,
When the pump circuit 11 is saturated, the lamp current I and the lamp voltage
The relationship of V is as shown in the characteristics of FIG. Also,
The amplifier circuit 11 does not saturate even after a certain time T has elapsed.
In such a case, a transition is made from characteristics to characteristics. Ramp RL
In the case of a high pressure discharge lamp, the point P ₁Start discharge at
P_TwoGo to Characteristics make the discharge lamp stable in an early stage
So that the lamp current I can flow more than the characteristics
It is. When the discharge lamp stabilizes, the point P_TwoFrom point P_ThreeTo
Move slowly. Timer time T depends on discharge lamp characteristics
Set the time required to transition to the characteristic. This
The discharge lamp performs rated operation with its characteristics.

Next, if the lamp RL is an incandescent lamp, after turning on the power switch SW, it operates at the characteristic point X.
This operating point X supplies less power than the rating of the incandescent lamp. When the timer 12 measures a certain time T, the characteristic shifts from the characteristic to the characteristic, so that the operating point shifts from the X point to the Y point. This operating point Y is set to the rated output of the incandescent lamp. As a result, the incandescent lamp performs rated operation with its characteristics. In this embodiment, for example, the lamp voltage of the discharge lamp is 90
It is particularly effective when the lamp voltage of the incandescent lamp is about 12 V at about V. As described above, if the drooping characteristic (output characteristic) of the lighting device is changed over time, it is not necessary to separately provide a lamp discriminating unit as in the above-described embodiments, and the circuit configuration is simplified.

[0040]

In the discharge lamp lighting device according to the first aspect, when another kind of lamp such as an incandescent lamp having a common socket is connected instead of the discharge lamp which is turned on by the first lighting means. However, the type of lamp is determined by the lamp determination means,
There is an effect that normal lighting can be performed by the second lighting means.

In the discharge lamp lighting device according to the second aspect, the power supply
Start the discharge lamp that shifts to the rated state after a certain period of time
Discharge lamp lighting device configured to operate and light
When an incandescent lamp is connected as a substitute for the discharge lamp
Before the elapse of the predetermined time, the incandescent lamp is turned on below the rating.
Lights, and after the lapse of the predetermined time, the incandescent lamp is turned on at the rated value.
Since the output characteristics of the lighting device are changed in such a manner, both the discharge lamp and the incandescent lamp can be operated at the rated lighting without providing the lamp discriminating means.

When the discharge lamp lighting device of the present invention is used for a headlight for a vehicle, even if the discharge lamp becomes unlit, a halogen bulb having high market availability can be used for an emergency, and safety can be secured. There is an advantage that you can.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention.

FIG. 2 is a circuit diagram of a first embodiment of the present invention.

FIG. 3 is an operation waveform diagram showing a lighting operation of the discharge lamp according to the first embodiment of the present invention.

FIG. 4 is an operation waveform diagram showing a lighting operation of the incandescent lamp according to the first embodiment of the present invention.

FIG. 5 is a circuit diagram of a second embodiment of the present invention.

FIG. 6 is an operation waveform diagram showing a lighting operation of a discharge lamp according to a second embodiment of the present invention.

FIG. 7 is an operation waveform diagram showing a lighting operation of an incandescent lamp according to a second embodiment of the present invention.

FIG. 8 is a circuit diagram of a third embodiment of the present invention.

FIG. 9 is a circuit diagram of a fourth embodiment of the present invention.

FIG. 10 is an explanatory diagram of an operation of a timer used in a fourth embodiment of the present invention.

FIG. 11 is an operation explanatory diagram of an amplifier circuit used in a fourth embodiment of the present invention.

FIG. 12 is a characteristic diagram showing output characteristics of a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 First lighting means 2 Second lighting means 3 Lamp discriminating means RL Lamp SW Power switch V ₁ Power supply

Continuation of front page (56) References JP-A-2-86096 (JP, A) JP-A-2-186597 (JP, A) JP-A-61-101997 (JP, A) JP-A-58-93196 (JP) JP-A-3-59995 (JP, A) JP-A-51-131083 (JP, U) JP-A-56-59675 (JP, U) JP-B-36-17129 (JP, B2) JP-B-sho 36-17130 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05B 37/00-39/10 H05B 41/24

Claims (2)

(57) [Claims] 1. A first lighting means for lighting a discharge lamp, a second lighting means for lighting a lamp other than the discharge lamp, and a lamp for applying a constant low voltage before performing an operation of lighting the discharge lamp. Lamp discriminating means for discriminating the type of the lamp by detecting the presence or absence of a lamp current by applying the discharge lamp to the discharge lamp using the first lighting means if the discharge lamp is adapted in accordance with the discrimination result by the lamp discriminating means. A discharge lamp lighting device, comprising: switching means for lighting an electric lamp, and for other lamps, lighting the lamp by a second lighting means. 2. A discharge lamp lighting device which is configured to start and turn on a discharge lamp which shifts to a rated state after a certain period of time from power-on, as an alternative lamp to the discharge lamp.
When connecting the lamp, the output characteristic of the constant the incandescent lamp prior to the expiration of the time lit-rated, the white <br/> heat lamp lighting device to light at rated the after elapse of the predetermined time A discharge lamp lighting device, comprising: means for changing a discharge lamp.