JPH06111964A - Starting circuit, discharge lamp lighting device, and lighting equipment - Google Patents

Abstract

(57) [Summary] [Object] To provide a starting circuit, a discharge lamp lighting device, and a lighting fixture capable of accurately detecting filament connection. [Configuration] When starting the fluorescent lamps FL1 and FL2, the inverter circuit 13 applies a low voltage to the fluorescent lamps FL1 and FL2. The removal of the oxide layer between the lamp pins and the sockets of the fluorescent lamps FL1, FL2 and the reduction of the contact resistance with the outer lead in the lamp pins reduce the detection of the mounting of the fluorescent lamps FL1, FL2. The oscillation of the inverter circuit 13 is stopped for 0.1 second, and the mounting of the fluorescent lamps FL1 and FL2 is detected. The fluorescent lamps FL1 and FL2 are mounted by detecting the applied DC voltage. When the mounting of all the filaments FL1a, FL1b, FL2a, FL2b is detected, the inverter circuit 13 applies a low voltage to the fluorescent lamps FL1, FL2, and then increases the voltage to increase the fluorescent lamps FL1, FL2. Light up.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starting circuit, a discharge lamp lighting device and a lighting fixture capable of surely detecting a filament.

[0002]

2. Description of the Related Art Conventionally, a discharge lamp lighting device for detecting the mounting of a filament of a discharge lamp applies a DC voltage to a lamp so that the lamp pin of the filament is connected to a socket before applying a starting voltage to the discharge lamp. It detects the formation of a closed loop and detects the installation of the filament of the discharge lamp.

[0003]

However, when the filament is detected by direct current, the oxide layer between the lamp pin and the socket or the outer lead in the lamp pin is detected even though the filament is normally connected. There is a problem that erroneous determination may occur due to the contact resistance with or the deposit on the tip of the lamp pin.

The present invention has been made in view of the above problems, and a starting circuit capable of accurately detecting the connection of filaments,
An object of the present invention is to provide a discharge lamp lighting device and a lighting fixture.

[0005]

According to a first aspect of the present invention, in a starting circuit, a voltage that does not start a discharge lamp is applied for a predetermined time, and then the voltage is increased to start the discharge lamp and a DC voltage is applied. Then, a starting circuit for detecting the mounting of the filament of the discharge lamp is provided, and after applying a voltage that does not start the discharge lamp to the discharge lamp for a predetermined time, oscillating is stopped for a predetermined time, and this voltage is applied. While stopped, a DC voltage is applied to the filament of the discharge lamp to detect the mounting of the filament, and after the mounting of the filament is detected, a voltage that does not start the discharge lamp is applied for a predetermined time. The discharge lamp is turned on by increasing the voltage.

According to a second aspect of the present invention, in the starting circuit according to the first aspect, the frequency of the voltage before the voltage application is stopped is made higher than the frequency after the voltage application is stopped, and the voltage The voltage before the application is stopped is made lower than the voltage after the application of the voltage is stopped.

According to a third aspect of the present invention, in the starting circuit according to the first or second aspects, the voltage application time before the voltage application is stopped is 0.3 seconds or more.

A discharge lamp lighting device according to a fourth aspect is a discharge lamp lighting device in which the starting circuit according to any one of the first to third aspects is connected to a step-up chopper circuit for boosting voltage.
The boost chopper circuit is not operated before the application of the voltage is stopped, and the boost chopper circuit is operated after the application of the voltage is stopped.

According to a fifth aspect of the present invention, there is provided a lighting circuit according to any one of the first to third aspects of the present invention, or the lighting circuit according to the fourth aspect.
The discharge lamp lighting device described above is provided.

[0010]

According to the first aspect of the present invention, in the starting circuit described above, the voltage which does not start the discharge lamp is applied for a predetermined time, the application of the voltage is stopped for a predetermined time, and when the application of the voltage is stopped,
To detect the filament attachment by applying a DC voltage to the discharge lamp, and after detecting the filament attachment, apply a voltage that does not start the discharge lamp for a predetermined time, and then increase the voltage to light the discharge lamp. A voltage is applied to detect the attachment of the filament by the DC voltage, the oxide film is removed, and the contact resistance is reduced, so that erroneous detection can be prevented.

According to a second aspect of the present invention, there is provided a starting circuit according to the first aspect, wherein the frequency of the voltage before the voltage application is stopped is made higher than the frequency after the voltage application is stopped. The voltage before the application is stopped is made lower than the voltage after the application is stopped to prevent the discharge lamp from lighting before starting.

According to a third aspect of the present invention, in the starting circuit according to the first or second aspects, the oxide film is removed because the voltage application time before the voltage application is stopped is 0.3 seconds or more. At the same time, the contact resistance can be reliably reduced, the filament can be reliably attached, and erroneous detection can be prevented.

A discharge lamp lighting device according to a fourth aspect is a discharge lamp lighting device in which the booster chopper circuit for boosting a voltage is connected to the starting circuit according to any one of the first to third aspects.
The boost chopper circuit is not operated before the voltage application is stopped, and the boost chopper circuit is operated after the voltage application is stopped, so that the initial voltage application can be easily made to be a low voltage, and the oxide film can be reliably formed. Since the contact resistance can be reduced while being removed, erroneous detection can be prevented.

According to a fifth aspect of the present invention, there is provided the lighting circuit according to any one of the first to third aspects, or the lighting circuit according to the fourth aspect.
Since the discharge lamp lighting device described above is provided, it is possible to prevent erroneous detection of filament attachment detection.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the lighting equipment of the present invention will be described below with reference to the drawings.

In FIG. 2, reference numeral 1 is a fixture body, and the fixture body 1 has V-shaped reflecting surfaces 2 and 2 formed on the lower surface thereof, and the lamp sockets 3 are provided at both ends of the reflecting surface 2 in the longitudinal direction. , 3 are mounted, and fluorescent lamps FL1, FL as discharge lamps are provided between these lamp sockets 3, 3.
2 is installed.

The circuit shown in FIG. 1 is housed in the instrument body 1. In the circuit shown in FIG. 1, a full-wave rectifier 11 is connected to a commercial AC power source E, and a boost chopper circuit 12 and a modified half-bridge type inverter circuit 13 are connected in cascade to the full-wave rectifier 11.

The boost chopper circuit 12 is composed of a boost choke L1, a field effect transistor Q1, a diode D1 and a capacitor C1, and the inverter circuit 13 is composed of two field effect transistors Q2 and Q3.

Further, a choke coil is provided between the drain and source of the field effect transistor Q3 of the inverter circuit 13.
Via L2, the capacitor C2 and the series circuit of the input winding Tra of the filament transformer Tr and the capacitor C3,
It is connected in parallel. The middle point of the balancer L3 is connected to the connection point of the choke coil L2 and the capacitor C2, the filament FL1a of the fluorescent lamp FL1 is connected to one end of the balancer L3, and the filament of the fluorescent lamp FL2 is connected to the other end. FL2a is connected.

Further, one end of the balancer L3 is a diode
It is connected to the output winding Trb of the filament transformer Tr via D2, the other end of the balancer L3 is connected to the output winding Trc of the filament transformer Tr via the diode D3, and this diode D3 is connected via the resistor R1 to the inverter. It is connected to the field effect transistor Q2 of the circuit 13. Also the output winding
Trb is connected to the negative electrode of the full-wave rectifier 11 via a series circuit of a diode D4 and a resistor R2.

Then, the filament FL of the fluorescent lamp FL1
1b is connected to the output winding Trd of the filament transformer Tr via the diode D5, and the filament FL2b of the fluorescent lamp FL2 is connected to the filament transformer Tr via the diode D6.
Connected to Tr output winding Trd. Also a diode
D5 is connected to the negative electrode of the full-wave rectifier 11 via the resistor R4. Further, the output winding Trd is connected to the negative electrode of the full-wave rectifier 11 via the capacitor C4.

Further, the connection point of the diode D4 and the resistor R2 is connected to one input terminal of the AND circuit 14, and the connection point of the diode D5 and the resistor R4 is connected to the other input terminal of the AND circuit 14. . And this AND circuit
The output terminal of 14 is connected to an inverter control unit 15 that controls the field effect transistors Q2 and Q3 of the inverter circuit 13.

The inverter control unit 15 is connected to the connection point of the diode D1 and the capacitor C1 via the diode D7 and the resistor R5 as a power source, and also connected to the zener diode ZD1 for constant voltage and the smoothing capacitor C5. Has been done.

Further, the field effect transistor Q1 of the boost chopper circuit 12 is controlled by the chopper control section 16, and this chopper control section 16 is connected to the connection point of the resistor R5 and the diode D7 via the diode D8 as a power source. At the same time, the zener diode ZD2 for constant voltage and the capacitor C6 for smoothing are connected.

Next, the operation of the circuit shown in FIG. 1 will be described with reference to the waveform chart shown in FIG.

First, the voltage of the commercial AC power source E is full-wave rectified by the full-wave rectifier 11, boosted by the step-up chopper circuit 12, reduced harmonics, and converted into high frequency by the inverter circuit 13, and the fluorescent lamp. Turn on FL1 and FL2. Further, the inverter control unit 15 and the chopper control unit 16 are activated when the commercial AC power source E is turned on.

When starting the fluorescent lamps FL1 and FL2, the inverter circuit 13 operates at a frequency of 130 kHz.
A low voltage that oscillates for 0.3 seconds and does not turn on the fluorescent lamps FL1 and FL2 is applied to the fluorescent lamps FL1 and FL2. In this way, by first applying a voltage to the fluorescent lamps FL1 and FL2, the contact resistance between the oxide layer between the lamp pins and the sockets of the fluorescent lamps FL1 and FL2 or the outer lead inside the lamp pins is reduced. , Fluorescent lamp FL1, FL2
Make sure to detect the attachment of the.

Next, the oscillation of the inverter circuit 13 is stopped for 0.1 second, and the mounting of the fluorescent lamps FL1 and FL2 is detected. To detect the mounting of the fluorescent lamps FL1 and FL2, a DC voltage is applied, and the filament FL2a of the fluorescent lamp FL2 from the resistor R1 is detected.
The AND circuit 14 detects that the current flows through the balancer L3, the filament FL1a of the fluorescent lamp FL1 and the diode D4, and the current flows from the resistor R3 to the filament FL2b of the fluorescent lamp FL2 and the filament FL1b of the fluorescent lamp FL1. Then do it.

When the installation of all the filaments FL1a, FL1b, FL2a, FL2b of the fluorescent lamps FL1, FL2 is not detected, the inverter control unit 15 causes the inverter circuit 13 to operate.
Does not oscillate.

On the other hand, when the installation of all the filaments FL1a, FL1b, FL2a, FL2b of the fluorescent lamps FL1, FL2 is detected, the inverter circuit 13 oscillates at a frequency of 120 kHz for 0.6 seconds, Apply a low voltage to FL1 and FL2 so that FL1 and FL2 do not light up, and then
The voltage is increased to turn on the fluorescent lamps FL1 and FL2.

Next, another embodiment will be described with reference to FIG.

The circuit shown in FIG. 4 is different from the circuit shown in FIG. 1 in that a timer circuit 17 is provided and a diode D8 is provided.
A switch SW1 driven by the timer circuit 17 is connected between the chopper control section 16 and the chopper control section 16.

At a low voltage at which the fluorescent lamps FL1 and FL2 are not lit, the oscillation frequency of the inverter circuit 13 before and after the application of the voltage is stopped is 120 kHz, and the operating state of the inverter circuit 13 is the same.

Further, as shown in FIG. 5, the boost chopper circuit 12 keeps the switch SW1 in the open state until the voltage application is stopped and the voltage is applied again after the power is turned on, and the chopper control unit 16 When the voltage is applied again without applying the voltage to the switch SW1, the switch SW1 is closed by the timer circuit 17 and the boost chopper circuit 12 is operated by the chopper controller 16.

By configuring the circuit as shown in FIG. 4, the output can be changed without changing the oscillation frequency of the inverter circuit 13.

[0036]

According to the starting circuit of the first aspect of the present invention, after applying a voltage for a predetermined time such that the discharge lamp does not start,
The application of voltage is stopped for a predetermined time, and when the application of this voltage is stopped, a DC voltage is applied to the discharge lamp to detect the mounting of the filament, and the discharge lamp does not start after detecting the mounting of the filament. After applying a certain voltage for a predetermined time, to increase the voltage to light the discharge lamp,
A voltage is applied to detect the attachment of the filament by the DC voltage, the oxide film is removed, and the contact resistance can be reduced, so erroneous detection can be prevented.

According to the starting circuit of the second aspect, in addition to the starting circuit of the first aspect, the frequency of the voltage before the voltage application is stopped is made higher than the frequency after the voltage application is stopped. It is possible to prevent the discharge lamp from lighting before starting by lowering the voltage before stopping the application of the voltage than the voltage after stopping the application.

According to the starting circuit of the third aspect, in addition to the starting circuit of the first or second aspect, the voltage application time before the application of the voltage is stopped is set to 0.3 seconds or more. In addition to being removed, the contact resistance can be reliably reduced, the filament can be reliably attached, and erroneous detection can be prevented.

According to the discharge lamp lighting device of the fourth aspect,
A boosting chopper circuit for boosting voltage is provided in any one of claims 1 to 3.
In the discharge lamp lighting device to which any one of the starting circuits is connected, the boost chopper circuit is not operated before the voltage application is stopped, and the boost chopper circuit is operated after the voltage application is stopped. Can be easily applied to a low voltage, the oxide film can be reliably removed, and the contact resistance can be reduced, so that erroneous detection can be prevented.

According to the lighting equipment of the fifth aspect, since the starting circuit according to any one of the first to third aspects or the discharge lamp lighting device according to the fourth aspect is provided in the main body of the luminaire, erroneous detection of filament attachment is detected. Can be prevented.

[Brief description of drawings]

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

FIG. 2 is a perspective view showing an appearance of the same lighting fixture.

FIG. 3 is a waveform chart showing the operation of the circuit shown in FIG. 1 above.

FIG. 4 is a circuit diagram showing another embodiment of the above.

5 is a waveform chart showing the operation of the circuit shown in FIG. 4 above.

[Explanation of symbols]

 12 Step-up chopper circuit FL1, FL2 Fluorescent lamp as discharge lamp

Claims (5)

[Claims] 1. A start for applying a voltage to the extent that the discharge lamp does not start for a predetermined time, then increasing the voltage to start the discharge lamp, and applying a DC voltage to detect the mounting of the filament of the discharge lamp. A circuit is provided, and a voltage to such a degree that the discharge lamp does not start is applied to the discharge lamp for a predetermined time, oscillation is stopped for a predetermined time, and while the application of the voltage is stopped, the filament of the discharge lamp is Applying a DC voltage to detect the mounting of the filament, and after detecting the mounting of the filament, apply a voltage for a predetermined time such that the discharge lamp does not start, and then increase the voltage to turn on the discharge lamp. Starting circuit characterized by. 2. The frequency of the voltage before the voltage application is stopped is made higher than the frequency after the voltage application is stopped, and the voltage before the voltage application is stopped after the voltage application is stopped. 2. The starting circuit according to claim 1, wherein the starting circuit has a voltage lower than the voltage. 3. The starting circuit according to claim 1, wherein the voltage application time before the voltage application is stopped is 0.3 seconds or more. 4. A discharge lamp lighting device in which the starting circuit according to any one of claims 1 to 3 is connected to a boost chopper circuit for boosting a voltage, wherein the boost chopper circuit is operated before stopping the application of the voltage. First, the discharge lamp lighting device is characterized in that the boost chopper circuit is operated after the voltage application is stopped. 5. A lighting fixture, comprising the starting circuit according to any one of claims 1 to 3 or the discharge lamp lighting device according to claim 4 in a fixture body.