JPH0696890A - Power supply unit, discharge lamp lighting device and luminaire - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a discharge lamp lighting device in which output is surely stopped after power is turned off and stress is less likely to occur. [Configuration] When the switch SW is closed, the inverter control unit 6
Power is supplied to the discharge lamp FL to turn it on at a high frequency. When the inverter circuit 5 operates, the chopper controller 4 operates the chopper controller 4. After the switch SW is closed, the capacitor C12 is charged, and after a lapse of a predetermined time after the start of power supply from the choke coil L2, the transistor Q4 is turned on, the current from the resistor R5 is bypassed by the transistor Q4, and the resistor R5 No power is supplied to the inverter control unit 6.
Even after the switch SW is opened, the voltage of the boost chopper circuit 2 does not drop sharply, but the transistor Q4 is kept on by the capacitor C11 until the current from the resistor R5 falls below a predetermined value. No voltage is applied to the inverter control unit 6, and the inverter control unit 6 maintains the output stopped state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, a discharge lamp lighting device, and a lighting fixture that reliably stop operation even after input is stopped.

[0002]

2. Description of the Related Art As a conventional discharge lamp lighting device of this type, for example, a structure shown in FIG. 6 is known.

In the discharge lamp lighting device shown in FIG. 6, a full-wave rectifier 1 is connected to a commercial AC power source E through a switch SW, and a boost chopper circuit 2 is connected to the full-wave rectifier 1, and these are connected. The power supply 3 is configured.

Further, the boost chopper circuit 2 is an inductor.
A series circuit of L1, the field effect transistor Q1 and the resistor R1 is connected, and a diode D1 and a capacitor C1 are connected in parallel to the series circuit of the field effect transistor Q1 and the resistor R1. Further, the chopper control unit 4 is connected to the gate of the field effect transistor Q1 via the resistor R2.

A modified half-bridge type inverter circuit 5 is connected to the boost chopper circuit 2.
The inverter circuit 5 has a field effect transistor Q2 and a field effect transistor Q3, and an inverter control unit 6 is provided at the gates of the field effect transistor Q2 and the field effect transistor Q3 via a resistor R3 or a resistor R4, respectively. It is connected.

Further, the inverter control unit 6 is connected to the connection point of the resistor R5 and the capacitor C2 in the series circuit of the resistor R5 and the capacitor C2 connected between the output terminals of the boost chopper circuit 2, and the capacitor C2 is connected to the capacitor C2. Zener diode ZD1 is connected in parallel. The output winding L2 is magnetically coupled and connected to the inductor L1, and the diode D2 and the resistor R6 are connected to the output winding L2.

Further, a series circuit of a capacitor C3 and a capacitor C4 is connected between the drain and the source of the field effect transistor Q3, and a chopper control section 4 is connected to a connection point of these capacitors C3 and C4. . Also, connect the choke coil L2 and the capacitor C5 in parallel with the series circuit of the capacitors C3 and C4.
Of the discharge lamp FL and the capacitor C6 are connected to the capacitor C5.

Then, the voltage of the commercial AC power source E is full-wave rectified by the full-wave rectifier 1, boosted by the boost chopper circuit 2, converted into high frequency by the inverter circuit 5, and the discharge lamp FL is turned on.

When the discharge lamp FL is turned off, the switch SW is opened to stop the output to the boost chopper circuit 2 and below.

[0010]

In the case of the conventional discharge lamp lighting device shown in FIG. 6, there is a hysteresis in the relationship between the input current and the input voltage of the inverter control unit 6, as shown in FIG. It has characteristics and current Idd
When (= voltage V0 / (resistance value of resistor R5)) is supplied with an input current equal to or higher than the current Idd start, the inverter control unit 6 starts outputting the voltage Vout, and when the input current is equal to or lower than the current Idd stop, the inverter control unit 6 Stops the output of the voltage Vout.

Therefore, as shown in FIG. 7 (a), even after the switch SW is opened, as shown in FIG. 7 (c), during the period in which the voltage V0 is not sufficiently discharged, the voltage Vdd is applied via the resistor R5. Is applied to the inverter control unit 6, the inverter control unit 6 produces an output as shown in FIG. 7B, and the inverter control unit 6 outputs a pulse even after the switch SW is turned off as shown in FIG. 7D. There is a problem in that the output is output and the discharge lamp FL blinks after the switch SW is turned off, causing stress in the inverter circuit 5.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a power supply device, a discharge lamp lighting device, and a lighting fixture in which output is reliably stopped and stress is less likely to occur after the power is turned off.

[0013]

According to a first aspect of the present invention, there is provided an output circuit for outputting electric power from a power source in a predetermined state, starting means for supplying electric power when the output circuit is started, and the output circuit. The circuit is provided with a stopping means for stopping the supply of electric power from the starting means after the circuit is started up, and a delay means for maintaining the stopped state of the stopping means for a predetermined time after the output of the power source is stopped.

According to a second aspect of the present invention, there is provided the discharge lamp lighting device, wherein the power supply device according to the first aspect is connected to discharge lamp lighting means for lighting the discharge lamp.

According to a third aspect of the present invention, there is provided a lighting apparatus in which the discharge lamp lighting device according to the second aspect is provided in the main body of the lighting apparatus to turn on the discharge lamp.

[0016]

In the power supply device according to the present invention, the power from the power source is put into a predetermined state and output by the output circuit, the power is supplied by the start-up means when the output circuit is started, and the start-up means is started after the output circuit is started. The power supply from the power supply is stopped by the stop means, and the delay means maintains the stopped state of the stop means for a predetermined time after the output of the power supply is stopped. Is not supplied, the output is surely stopped after the power is turned off, and stress is not generated in the output circuit.

In the discharge lamp lighting device according to the second aspect, the discharge lamp lighting means for lighting the discharge lamp is connected to the power supply device according to the first aspect, and therefore, after the power from the power supply is turned off, the starting means is operated for a predetermined time. Since the power is not supplied, the output is surely stopped after the power is turned off, and the output circuit is not stressed.

According to a third aspect of the present invention, in order to turn on the discharge lamp by providing the discharge lamp lighting device according to the second aspect in the main body of the luminaire, after turning off the electric power from the power supply, the starting means supplies the electric power for a predetermined time. Is not supplied, the output is surely stopped after the power is turned off, and stress is not generated in the output circuit.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A lighting apparatus according to an embodiment of the present invention will be described below with reference to the drawings. It should be noted that the portions corresponding to the conventional example shown in FIG.

In FIG. 2, reference numeral 11 denotes a luminaire main body, a reflecting surface is formed on the lower surface of the luminaire main body 11, and lamp sockets 12, 12 are attached to both ends of the reflecting surface. A discharge lamp FL is connected in between. In addition, the circuit shown in FIG. 1 is built in the luminaire main body 11.

As shown in FIG. 1, a full-wave rectifier 1 is connected to a commercial AC power source E via a switch SW, and a boost chopper circuit 2 is connected to the full-wave rectifier 1 to form a power source 3. To be done.

Further, the boost chopper circuit 2 includes an inductor.
A series circuit of L1, the field effect transistor Q1 and the resistor R1 is connected, and a diode D1 and a capacitor C1 are connected in parallel to the series circuit of the field effect transistor Q1 and the resistor R1. Further, the chopper control unit 4 is connected to the gate of the field effect transistor Q1 via the resistor R2.

A modified half-bridge type inverter circuit 5 as an output circuit is connected to the boost chopper circuit 2. This inverter circuit 5 has a field effect transistor Q2 and a field effect transistor Q3, the inverter control unit 6 is connected to the gate of the field effect transistor Q3 via a resistor R4, and is connected to the gate of the field effect transistor Q3. Is connected to the resistor R3.

Further, the inverter control unit 6 includes a resistor R5 as a starting means connected between the output terminals of the boost chopper circuit 2, a diode D5 and a smoothing capacitor C2.
The connection point of the diode D5 and the capacitor C2 in the series circuit of is connected, and the zener diode ZD1 for constant voltage is connected in parallel to the capacitor C2. And inductor
An output winding L2 is magnetically coupled and connected to L1, and a diode D2 and a resistor R6 are connected to this output winding L2. Also, in parallel with the diode D5 and the capacitor C2, the collector of the transistor Q4 as a stopping means,
The emitter is connected. Further, a series circuit of a Zener diode ZD2, a resistor R11 and a capacitor C11 as a delay means is connected between the connection point of the diode D2 and the resistor R6 and the negative electrode of the full-wave rectifier 1. The connection point of the resistor R11 and the capacitor C11 is connected to the base of the transistor Q4 via the resistor R12.

Further, a series circuit of a capacitor C3 and a capacitor C4 is connected between the drain and source of the field effect transistor Q3, and a chopper control section 4 is connected to a connection point of these capacitors C3 and C4. . Also, connect the choke coil L2 and the capacitor C5 in parallel with the series circuit of the capacitors C3 and C4.
Of the discharge lamp FL and the capacitor C6 are connected to the capacitor C5.

Next, the operation of the above embodiment will be described with reference to FIG.

First, when the switch SW is closed, the full-wave rectifier 1 full-wave rectifies the voltage of the commercial AC power source E. Then, electric power is supplied to the inverter control unit 6 via the resistor R5 and the diode D5 to operate the field effect transistor Q2 and the field effect transistor Q3 to operate the inverter circuit 5
To generate a high frequency and turn on the discharge lamp FL at a high frequency.

When the inverter circuit 5 operates,
The voltage is divided by the capacitors C3 and C4 to supply power to the chopper control unit 4, the chopper control unit 4 operates to drive the field effect transistor Q1, and the boost chopper circuit 2 operates to boost the voltage. Supply power to.

After the switch SW is closed, the output winding
After the voltage from L2 exceeds the Zener voltage of Zener diode ZD2, capacitor C11 is charged, and after a lapse of a predetermined time, current is supplied to the base of transistor Q4 to turn on transistor Q4 and the current from resistor R5. Is bypassed by the transistor Q4 and no power is supplied from the resistor R5 to the inverter control unit 6.

On the other hand, when the discharge lamp FL is turned off, the switch SW is opened to stop the output to the boost chopper circuit 2 and below.

Then, as shown in FIG. 3A, even after the switch SW is opened and the chopper operation of the boost chopper circuit 2 is stopped, the voltage of the boost chopper circuit 2 does not drop sharply. However, until the current from the resistor R5 becomes equal to or lower than a predetermined value, the transistor C4 is maintained in the ON state by the capacitor C11 and no voltage is applied to the inverter controller 6 as shown in FIG. The inverter control unit 6 stops the output as shown in FIG. 3 (b), the inverter control unit 6 opens the switch SW as shown in FIG. 3 (d), and the pulse is generated after the operation of the boost chopper circuit 2 is stopped. Is not output. Therefore, after the switch SW is turned off, the field effect transistor Q2 and the field effect transistor Q3 do not oscillate, the discharge lamp FL does not light, and the field effect transistor Q2 and the field effect transistor Q3 of the inverter circuit 5 are not stressed.

As shown in FIG. 4, the capacitor C11
Is connected in series with the resistor R5, the base of the transistor Q4 is connected, the capacitor C11 is charged by the current from the resistor R5, and the transistor Q4 is turned off after a predetermined time after the switch SW is closed. The transistor Q4 may be turned on after a predetermined time elapses after opening.

Further, as shown in FIG. 5, diode D5
Even if the connection position is changed, the circuit operates similarly to the circuit shown in FIG.

[0034]

According to the power supply device of the first aspect, the power from the power source is brought into a predetermined state and output by the output circuit, and when the output circuit is started, the starting means supplies the power to start the output circuit. After that, the power supply from the starting means is stopped by the stop means, and the delay means maintains the stopped state for a predetermined time after the output of the power supply is stopped. Since the power is not supplied from the starting means, it is possible to surely stop the output after the power is turned off and prevent the output circuit from being stressed.

According to the discharge lamp lighting device of the second aspect,
Since the discharge lamp lighting means for lighting the discharge lamp is connected to the power supply device according to claim 1, after the power from the power supply is turned off, the power is not supplied from the starting means for a predetermined time. Therefore, the output is surely stopped after the power is turned off. However, stress can be prevented from occurring in the output circuit.

According to the lighting fixture of claim 3, the discharge lamp lighting device according to claim 2 is provided in the fixture body to light the discharge lamp. Therefore, after turning off the power from the power source,
Since the power is not supplied from the starting means for a predetermined time, it is possible to reliably stop the output after the power is turned off and prevent the output circuit from being stressed.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a discharge lamp lighting device of the present invention.

FIG. 2 is a perspective view showing a lighting fixture incorporating the above discharge lamp lighting device.

FIG. 3 is a waveform diagram showing an operation of the discharge lamp lighting device shown in FIG. 1 above. (A) Voltage V0 (b) Voltage VCH (c) Voltage Vdd (d) Voltage VOUT

FIG. 4 is a circuit diagram showing a part of a discharge lamp lighting device of another embodiment of the same.

FIG. 5 is a circuit diagram showing a part of a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 6 is a circuit diagram showing a conventional discharge lamp lighting device.

7 is a waveform diagram showing the operation of the discharge lamp lighting device shown in FIG. 6 above. (A) Voltage V0 (b) Voltage VCH (c) Voltage Vdd (d) Voltage VOUT

FIG. 8 is a graph showing a relationship between an operating current and an operating voltage of the same inverter control unit.

[Explanation of symbols]

 3 Power source 5 Inverter circuit as output circuit 11 Lighting fixture body C11 Capacitor as delay means Q4 Transistor R5 as stop means Resistor as start means

Claims (3)

[Claims] 1. An output circuit for outputting electric power from a power source in a predetermined state and outputting the electric power, starting means for supplying electric power at the time of starting the output circuit, and supply of electric power from the starting means after starting the output circuit. A power supply device comprising: a stopping means for stopping and a delay means for maintaining the stopped state of the stopping means for a predetermined time after the output of the power supply is stopped. 2. A discharge lamp lighting device, characterized in that discharge lamp lighting means for lighting a discharge lamp is connected to the power supply device according to claim 1. 3. A lighting fixture, characterized in that the discharge lamp lighting device according to claim 2 is provided in the fixture body to light the discharge lamp.