JP2964651B2 - Lighting control 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 lighting control device for controlling the lighting of an incandescent lamp load and a discharge lamp load independently with a small number of switching elements.

[0002]

2. Description of the Related Art Conventionally, in order to produce various scenes with a single lighting device, for example, a fluorescent lamp and an incandescent lamp (such as a mini-halogen lamp) are housed inside the lighting device to perform load switching and dimming. It has been proposed. In the case of lighting loads having different characteristics, in particular, a plurality of lighting controls of a fluorescent lamp and an incandescent lamp, as shown in FIG. 10, the loads RL ₁ and RL ₂ are individually controlled by two completely independent lighting control circuits ₁ and ₂ . As shown in FIG. 11, the power supply E is made common and the load R is independently controlled by the individual inverter circuits K ₁ and K _2.
There is a method of controlling L ₁ and RL ₂ to turn on / off and dimming.

In the circuit shown in FIG. 11, a series circuit of switching elements SW ₁ and SW ₂ and a switching element S
A series circuit of W ₃ and SW ₄ is connected in parallel to a common DC power supply E. The switching elements SW ₁ and SW ₂ are turned ON / OFF alternately by the drive circuit 11.
At both ends of the switching elements SW _1, the series resonant circuit of inductor L ₁ and capacitor C ₂ is connected. The both ends of the capacitor C _2, the load RL ₁ are connected via a capacitor C ₁ for DC component cut. On the other hand, the switching elements SW ₃ and SW ₄ are alternately turned on / off by the drive circuit 12. Switching element SW
_The primary winding of the transformer T is connected to both ends of the transformer ₃ via a DC component cutting capacitor C3. The secondary winding of the transformer T, load RL ₂ through the inductor L ₂
Is connected.

In these circuit systems, the loads RL ₁ , RL
₂ is independent, so when controlling one, the other is not affected and it is easy to control.
In the configuration of 0, there is a problem that two lighting control circuits 1 and 2 connected to the AC power supply Vs are required independently, and in the configuration of FIG. 11, it is used in the inverter circuits K ₁ and K _2. Switching elements SW ₁ , SW ₂ , SW ₃ , S
The number of W ₄ becomes many, there has been a problem that the cost is high.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a lighting control device for controlling lighting of an incandescent lamp load and a discharge lamp load. It is an object of the present invention to share a part of a control switching element and to arbitrarily independently control each load.

[0006]

Lighting the lighting control apparatus of the present invention, in order to solve the problems] To solve the above problem, as shown in FIG. 1, the diode D ₁ to the first and second bridge circuit composed of D ₄ Of the DC power supply E via the first and second switching elements SW ₁ and SW ₂ respectively.
, A second terminal of the DC power supply E is connected to a first DC side terminal of the diode bridge circuit, and a first terminal of the diode bridge circuit is connected to a second DC side terminal. To the third switching element SW ₃ ,
Connected between the first or second terminal of the first load circuit including the incandescent lamp load RL ₂ and the first AC terminals of the diode bridge circuit DC power source E, a second containing the lamp load RL ₁
Is connected between the second AC terminal of the diode bridge circuit and the first or second terminal of the DC power supply E, and the second and third switching elements SW ₂ and SW ₃ are alternately switched at a variable frequency. a discharge lamp control means for oN / OFF, the ratio of the first switching element SW ₁ of the third switching element SW ₃ and alternately oN / OFF is to operation period and the operation period for pause of the first switching element variable in And incandescent lamp control means.

[0007]

According to the present invention, the third switching element S
Share W _3, performs the inverter operation of driving the load circuit including the incandescent lamp load RL ₂ by ON / OFF the first switching element SW ₁ and the third switching element SW ₃ alternately, the inverter operation intermittently rested, by the pause interval is variable, the average current through the incandescent lamp load RL ₂ and adjustable, it is possible to control dimming incandescent load RL _2. Further, the second switching element SW ₂ and the third switching element SW ₃
Are alternately turned ON / OFF to obtain a discharge lamp load RL.
Perform an inverter operation of driving the load circuit including a _1, by the frequency of the inverter operation variable, lamp load RL a high-frequency current to the adjustable flowing in _the discharge lamp load RL ₁ to control dimming Can be.

[0008]

FIG. 1 is a circuit diagram of an embodiment of the present invention. E
Is a DC power supply, which is, for example, a DC voltage obtained by rectifying and smoothing a commercial AC power supply. SW ₁ to SW ₃ is a switching element, for example, made of a transistor or FET.
D ₁ to D ₄ are diodes, C ₁ to C ₃ are capacitors. C _1, C ₃ is a coupling capacitor for DC component cut does not affect the resonance effect in the mass. Also, C ₂ is a capacitor for resonance between the inductor L _1. L ₁ is resonant and current limiting inductors, T is a transformer. RL ₁ is a discharge lamp load such as a fluorescent lamp, R
L ₂ is an incandescent lamp load.

[0009] Switching element SW₁, SW_TwoIs it
Each load RL_Two, RL₁Corresponding to the switching element S
W_ThreeAre common switching elements. Each sui
Switching element SW₁, SW_TwoAnd switching element SW_Three
Between the diode D_Two, D_ThreeIs inserted
And each load RL₁, RL_TwoDoing operational separation between
I have. That is, the diode D_Two, D_ThreeIf there is no
Load RL₁, RL_TwoBecomes a parallel connection. Daio
Code D_Two, D_ThreeBy inserting, for example, the load R
L₁Inductor L corresponding to₁The current flowing through the switch
Element SW₁Diode D
_Two, D_ThreeAre reversed, and the inductor L ₁Current is
Switching element SW_TwoOnly flows through. Also, Daio
Code D_Two, D_Three, The switching element S
W_ThreeThere is no path for reverse current to flow to
Do D₁, D_FourAre connected.

Next, FIG. 2 shows the configuration of a control circuit used in this embodiment. This circuit corresponds to the switching element S shown in FIG.
This is a circuit for generating drive signals A, B and C for W ₁ , SW ₂ and SW ₃ . In the figure, 3 is a astable multivibrator, and determines the idle period of the switching element SW _1. Reference numeral 4 denotes a PWM control circuit including a general-purpose switching regulator IC (μPC494 manufactured by NEC Corporation). 5 is a level shifter circuit, and a PWM control circuit 4
The signal obtained at the output terminal (pin 11) to the level shift, and is a circuit for transmitting to the control electrode of the switching element SW ₁ and SW ₂ of the high potential side.

Here, a general-purpose IC constituting the PWM control circuit 4 will be briefly described. This IC is used with a control power supply Vcc applied between a power supply terminal (pin 12) and a ground terminal (pin 7), and a capacitor connected between a capacitor terminal (pin 5) and a ground terminal. An oscillator that oscillates at a frequency corresponding to the time constant of the resistor connected between the resistor terminal (6th pin) and the ground terminal is built in. The first oscillation output is obtained by alternating between a short-circuit state and an open state between the first open collector terminal (8th pin) and the first open emitter terminal (9th pin). The second oscillation output is obtained by alternately switching between a state where the second open collector terminal (the 11th pin) and the second open emitter terminal (the 10th pin) are short-circuited and an open state. . Here, when the output control terminal (the 13th pin) is dropped to the ground level, a single-ended operation for one stone is performed, and the first oscillation output coincides with the second oscillation output. Terminal (Pin 13) as reference voltage output terminal (Pin 14)
When the reference voltage Vref is set to the level of the reference voltage Vref, the push-pull operation for two stones is performed, and the first oscillation output and the second oscillation output take an opposite state after a predetermined dead-off time. This dead-off time depends on the control power supply V
The level can be set by dividing the cc level and inputting it to the dead-off time control terminal (pin 4).

The operation of this embodiment will now be described with reference to the operation waveform diagram of FIG.
This will be described with reference to FIG. Time constant end of PWM control circuit 4
Variable resistor VR connected to the child (6th and 5th pins)_TwoAnd co
Capacitor C₆ Determines the oscillation cycle. First oscillation
The output (8th pin) has a rectangular wave as shown in FIG.
A signal is output. To the second oscillation output (pin 11)
Outputs a rectangular wave signal as shown in FIG.
The first oscillation output and the second oscillation output are at a high level.
And the Low level are opposite. The first oscillation output (Pin 8
3), as shown in FIG.
Element SW_Three Input to the gate. On the other hand, the second oscillation
Output (11th pin) is at High level
And the resistor R₇Through the transistor Q₁And Q_TwoConsists of
The current I is supplied to the first current mirror circuit.₁Flows and the same current
Is transistor Q_TwoCollector current I_TwoFlows as
And this current I_TwoIs transistor Q_Three, Q_FourMore
Flows through the second current mirror circuit, and the same current flows through the second current mirror circuit.
Jista Q_FourCollector current I _FourFlows as This current
I_FourIs the resistance R₉To the buffer IC
Input to the switching element SW_Twoof
Drive the gate. The power supply of the level shifter circuit 5 is
Switching element SW_TwoResistor R₈Through
And capacitor C_FiveObtained by the charged DC voltage
You. Switching element SW_TwoThe gate potential of FIG.
As shown in FIG. 3D, the signal of FIG.
The potential is level-shifted. Astable multibar
The output of the vibrator 3 is a variable resistor VR₁And capacitor C
_Four3 (e) is a cycle determined by the time constant of
As described above, the High level is maintained only for a predetermined time. This nothing
The oscillation output of the stable multivibrator 3 and the PWM control circuit
The second oscillation output of the path 4 (the 11th pin) is
ND, and as shown in FIG.
Only a square wave signal can be obtained. This signal is
Switching element SW via lid circuit 5₁At the gate
Is entered. Switching element SW₁The gate potential of
As shown in FIG. 3G, the signal of FIG.
The potential is level-shifted. Therefore, the switch
Element SW₁Is intermittently driven ON / OFF,
Switching element SW_TwoIs driven ON / OFF continuously
Will be. Also, the switching element SW_Three Is a switch
Element SW_Two OFF when ON, switching
Element SW_Two Is turned on when is turned off.

[0013] By providing the control circuit as described above, it is possible to control the lamp load RL ₁ incandescent load RL ₂ independently. First, it made in ON / OFF always alternating the switching element SW ₂ and SW _3, moreover since there is no one idle period of the switching element SW _2,
The anode potential of the diode D ₃ becomes continuous rectangular wave voltage, the voltage across the capacitor C ₂ by the series resonance of the inductor L ₁ and capacitor C ₂ is a sine wave voltage.
This is applied to the load RL ₁ through the capacitor C ₁ of the DC component cutting, high-frequency current flows through the load RL _1. Then, the oscillation frequency of the PWM control circuit 4 is changed to the resistance VR.
By varying with _2, proper load current flows due to current limiting action of the inductor L _1. Note that the current flowing through the lamp load RL ₁ no rest period, the continuously flowing, does not occur like the specific extinction in the discharge lamp.

On the other hand, the incandescent lamp load RL_TwoAbout the operation of
Indicates that the output of the astable multivibrator 3 is High level.
The switching element SW₁And SW_Threeof
ON / OFF is always performed alternately and periodically.
D_TwoAnode voltage becomes a square wave voltage, and DC component
Capacitor C_ThreeTo the primary winding of the transformer T via
Is supplied with an AC voltage, and the output of the load RL_TwoLights up
I do. The output of the astable multivibrator 3 is Lo.
When it is at the w level, the switching element SW ₁Is O
To maintain the FF state, load RL_TwoIs supplied with current
Not. The output of the astable multivibrator 3 is Hi.
Ratio of period at gh level to period at low level
By adjusting the load RL_TwoThe average current flowing through
Can be adjusted. Incandescent lamp load RL_TwoIs intermittent
Since flicker does not occur even if the current flows,
The incandescent lamp load RL_TwoCan be dimmed freely
You. The discharge lamp load RL₁To control the output of
When the vibration frequency is changed, the incandescent lamp load RL_TwoElectricity flowing through
The current cycle also changes, but the average current does not change.
Heat lamp load RL_TwoOutput does not change. Therefore, discharge
Light load RL₁And incandescent lamp load RL_TwoDimming individually and independently
can do.

FIG. 4 is a circuit diagram of a second embodiment of the present invention. In this embodiment, in the first embodiment shown in FIG.
Connecting a first load circuit connected to both ends of the diode D ₁ is connected to both ends of the switching elements SW _1, a second load circuit connected to both ends of the diode D ₄ to both ends of the switching element SW ₂ The operation is the same as that of the first embodiment shown in FIG.

FIG. 5 is a circuit diagram of a third embodiment of the present invention. In this embodiment, in the second embodiment shown in FIG.
It is obtained by disposing the switching element SW ₃ which is shared by the positive side of the DC power source E, its operation, Figure 1
This is the same as the first embodiment shown in FIG.

FIG. 6 shows a control used in the fourth embodiment of the present invention.
It is a principal part circuit diagram of a circuit. In this embodiment, the switch on the high potential side
Switching element SW₁, SW_TwoSignal transmission to the
Instead of using the lid circuit 5, the transformer T₁, T_TwoBy
Is what you do. When using such a transformer
Is the switching element SW₁, SW_TwoRise of drive signal
Back electromotive force is generated in the secondary winding at the time of falling.
Ching element SW₁, SW _TwoReverse bias the control terminal of
Can be convenient.

[0018] FIGS. 7 to 9 show the lighting circuit of the discharge lamp load RL ₁ used in the fifth to seventh embodiment of the present invention. In the circuit of Figure 7 utilizes the resonance of the primary winding of the inductance component and the capacitor C of the transformer T, the inductor L has a current limiting element of the lamp load RL _1.
In the circuit of Figure 8, likewise, it utilizes the resonance of the inductance component and the capacitor C ₁ of the primary winding of the transformer T, the current limiting element is a capacitor C _2. In the circuit of FIG. 9, the capacitor C is used as a current limiting element, and the capacitor C and the inductor L constitute a resonance circuit.

[0019]

As described above, according to the present invention, in an illumination lighting control device for independently controlling the lighting of an incandescent lamp load and a discharge lamp load, a switching element for control is partially shared and the incandescent lamp load is used. Dimming the average current by intermittent oscillation, and dimming the discharge lamp load by variable frequency with continuous oscillation, so that each load can be controlled independently without being affected by each other. is there.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a first embodiment of the present invention.

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

FIG. 3 is an operation waveform diagram of the first embodiment of the present invention.

FIG. 4 is a circuit diagram of a second embodiment of the present invention.

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

FIG. 6 is a circuit diagram of a control circuit used in a fourth embodiment of the present invention.

FIG. 7 is a circuit diagram of a load circuit used in a fifth embodiment of the present invention.

FIG. 8 is a circuit diagram of a load circuit used in a sixth embodiment of the present invention.

FIG. 9 is a circuit diagram of a load circuit used in a seventh embodiment of the present invention.

FIG. 10 is a block diagram of a conventional example.

FIG. 11 is a circuit diagram of another conventional example.

[Explanation of symbols]

SW ₁ First switching element SW ₂ Second switching element SW ₃ Third switching element RL ₁ Discharge lamp load RL ₂ Incandescent lamp load E DC power supply D ₁ First diode D ₂ Second diode D ₃ Third diode D ₄ fourth diode

Claims (1)

(57) [Claims] 1. A first and a second diode bridge circuit.
Are connected to a first terminal of a DC power supply via first and second switching elements, respectively, and a second terminal of the DC power supply is connected to a first DC side terminal of the diode bridge circuit. Connecting a third switching element between a first DC side terminal and a second DC side terminal of the diode bridge circuit, and connecting a first load circuit including an incandescent lamp load to a first AC of the diode bridge circuit; And a second load circuit including a discharge lamp load connected between the second terminal of the diode bridge circuit and the first or second terminal of the DC power supply. Connected between the terminals, and the second and third switching elements are alternately turned on at a variable frequency.
Discharge lamp control means for N / OFF, and ON / OFF of the first switching element alternately with the third switching element
An incandescent lamp control unit that varies a ratio between an operation period in which the first switching element is operated and an operation period in which the first switching element is stopped.