JPH10241878A - Discharge lamp lighting device and lighting device - Google Patents

Abstract

(57) [Problem] To provide a discharge lamp lighting device for appropriately preheating a discharge lamp with a simple configuration. SOLUTION: A direct current of a direct current power supply E is converted into a high frequency by an inverter circuit 11 to preheat filaments FL1a and FL1b. In this state, since the discharge detection circuit 12 does not form a closed circuit in terms of DC, the DC component is not applied to the capacitor C3 and the capacitor C3 is not charged. When the fluorescent lamp FL1 is discharged and turned on, a DC component is applied to the capacitor C3. When the voltage becomes higher than the reference power supply E1, it is determined that the fluorescent lamp FL1 is discharged and turned on. If discharge is detected in a state where preheating is required, the output of the inverter circuit 11 is reduced by negative feedback, and the filaments FL1a, FL1
Preheat 1b. When the preheating is sufficient, the voltage of the reference power supply E1 is increased by a timer or the like, the output of the inverter circuit 11 is increased, and the fluorescent lamp FL1 is started and turned on.

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 device and an illuminating device that appropriately heat a discharge lamp.

[0002]

2. Description of the Related Art Generally, a discharge lamp lighting device turns on a discharge lamp after preheating the discharge lamp.

That is, before lighting a discharge lamp,
The discharge lamp is preheated with a voltage lower than the starting voltage of the discharge lamp, and thereafter, a predetermined time is measured by a timer or the like, and after the lapse of the predetermined time, the voltage applied to the discharge lamp is increased to start and light the discharge lamp.

When preheating a discharge lamp,
If the ignition lamp is instantaneously turned on due to a variation in the starting voltage, or if the preheating condition is insufficient, or if the preheating condition deviates from the appropriate value, the discharge lamp may be blackened early.

For this reason, the starting voltage is set with a sufficient margin, and a control circuit for controlling the preheating voltage to be constant or a power supply fluctuation compensation circuit is added.

[0006]

As described above, if the preheating of the discharge lamp is not appropriate, there is a problem that the discharge lamp is blackened at an early stage and the structure for properly preheating is complicated. .

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a discharge lamp lighting device and a lighting device that can appropriately preheat a discharge lamp with a simple configuration.

[0008]

According to a first aspect of the present invention, there is provided a discharge lamp lighting device for lighting a discharge lamp having a filament; discharge detection means for detecting discharge of the discharge lamp; And control means for reducing the output of the discharge lamp lighting means and preheating the filament when the discharge is detected. When the discharge of the discharge lamp is detected by the discharge detecting means, and the discharge of the discharge lamp is detected, the output of the discharge lamp lighting means is reduced by the control means, so that the discharge is performed before the discharge lamp is sufficiently preheated. To prevent start-up lighting and to preheat properly.

According to a second aspect of the present invention, there is provided the discharge lamp lighting device according to the first aspect, wherein the discharge detecting means is not DC-connected to the discharge lamp lighting means. Of these, by cutting off the DC component, the discharge of the discharge lamp is accurately detected with a simple configuration.

According to a third aspect of the present invention, there is provided the discharge lamp lighting device according to the first or second aspect, wherein the discharge lamp lighting means preheats the discharge lamp and the filament by at least one of a weak discharge and a leakage current. Preheat the discharge lamp under stable preheating conditions.

According to a fourth aspect of the present invention, in the discharge lamp lighting device, the discharge detecting means has a filter for removing a lighting frequency of the discharge lamp. Eliminates the effects of flow and accurately detects the discharge of the discharge lamp with a simple configuration.

According to a fifth aspect of the present invention, there is provided a lighting device including the discharge lamp lighting device according to any one of the first to fourth aspects and a fixture main body in which the discharge lamp lighting device is provided.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a lighting device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing the lighting device. As shown in FIG. 2, the thin disk-shaped device main body 1 is attached to a hook ceiling (not shown) by an adapter 2 and is attached to the lower surface of the device main body 1. Is mounted with a holder body 3 to which fluorescent lamps FL1 and FL2 as discharge lamps are mounted. The fluorescent lamps FL1 and FL2 are covered with a light-transmitting shade 4 together with the holder body 3. And the discharge lamp lighting device 5 is accommodated in the appliance main body 1.

FIG. 1 is a circuit diagram showing a discharge lamp lighting device. As shown in FIG.
Inverter circuit as discharge lamp lighting means in DC power supply E
The inverter circuit 11 is connected to one end of the filaments FL1a and FL1b of the fluorescent lamp FL1 via a DC cut capacitor C1 and an inductor L1. The starting capacitor C2 is connected. Note that the inverter circuit 11
Is configured such that when the voltage of the fluorescent lamp FL1 rises due to a point or the like, the output increases up to the set voltage.

Further, the inductor L1 on the side having the DC cut capacitor C1 and the filament FL of the fluorescent lamp FL
A discharge detection circuit 12 as discharge detection means is connected to a connection point with one end of the fluorescent lamp 1a.
It has a low-pass filter 14 for removing the AC component of the lighting frequency of FL1, a series circuit of resistors R1 and R2, and a capacitor C3 connected in parallel with the resistor R2. A connection point between the resistors R1 and R2 is connected to one input terminal of a comparator 15 as control means, and the other input terminal of the comparator 15 is connected to a reference power supply E1 having a variable output voltage. The output terminal 15 changes the oscillation frequency of the inverter circuit 11 according to the voltage.
It is connected to the inverter circuit 11 via the FO16.

A similar inverter circuit is provided separately for the fluorescent lamp FL2.

Next, the operation of the above embodiment will be described.

First, the DC of the DC power supply E is supplied to an inverter circuit.
The frequency is converted to high frequency by 11 to preheat the filaments FL1a and FL1b of the fluorescent lamp FL1. In this state, as shown in the equivalent circuit of FIG. 3, the resistance R1a of the filaments FL1a and FL1b,
Although the starting capacitor C2 is connected via R1b, a direct current is not formed by the capacitors C1 and C2, so that no DC component is applied to the capacitor C3 and the capacitor C3 is not charged.

When the fluorescent lamp FL1 is discharged and turned on, the resistor RFL is connected as shown in the equivalent circuit of FIG. 4, so that a series circuit of the resistor RFL, the resistor R1 and the resistor R2 is formed. When a DC component is applied to the capacitor C3 and the voltage of the capacitor C3 becomes higher than the reference voltage E1,
It can be determined that the fluorescent lamp FL1 has been discharged and turned on.
In the preheating state of the filaments FL1a and FL1b of the fluorescent lamp FL1, the voltage of the reference power supply E1 is kept low.

When the discharge of the fluorescent lamp FL1 is detected in a state where the filaments FL1a and FL1b need to be preheated,
The output of the inverter circuit 11 is reduced by the negative feedback, and the filaments FL1a and FL1b are again preheated by a non-discharged state, a slight discharge state such as a glow discharge, or a leakage current flowing on the surface of the fluorescent lamp FL1. afterwards,
When the filaments FL1a and FL1b are sufficiently preheated, the voltage of the reference power supply E1 is increased by a timer or the like, the output of the inverter circuit 11 is increased, and the fluorescent lamp FL1 is started and turned on. Based on the reference power source E1, the detection state such as the end of life of the fluorescent lamp FL1 is set. In this way, since the filaments FL1a and FL1b are sufficiently preheated by glow discharge or the like, there is no need to consider variations in the preheating voltage and the like, so that a power supply fluctuation compensation circuit or a circuit for correcting the variations is not required. The structure is simplified, and variations in preheating conditions can be eliminated, the deterioration of the filaments FL1a and FL1b is reduced, and the life of the fluorescent lamp FL1 can be extended. In addition, since the filaments FL1a and FL1b are preheated in a glow discharge state or the like, a little brightness can be obtained.

On the other hand, when the fluorescent lamp FL1 is not mounted, as shown in an equivalent circuit of FIG.
In No. 12, since no direct current is formed by the capacitors C1 and C2, no direct current is applied to the capacitor C3, and the capacitor C3 is not charged. If this state continues for a predetermined time or longer, it is determined that the fluorescent lamp FL1 is not connected, and the output of the inverter circuit 11 is stopped.

In order to detect the end of the life of the fluorescent lamp FL1, for example, when a half-wave discharge is performed from the filament FL1a to the filament FL1b of the fluorescent lamp FL1, electric charges are similarly accumulated in the capacitor C3. When the voltage of the capacitor C3 becomes higher than the voltage of the reference power supply E1, the output of the inverter circuit 11 is reduced or stopped at the end of the life of the fluorescent lamp FL1.

On the other hand, the filament FL1b of the fluorescent lamp FL1
From the capacitor C3 to the filament FL1a, the voltage of the capacitor C3 is reversed.
Is not higher than the voltage of the reference power supply E1, so that the output of the inverter circuit 11 does not decrease based on the output of the comparator 15, but as the voltage of the fluorescent lamp FL1 increases, the end of the life of the fluorescent lamp FL1 The output is reduced or stopped by the inverter circuit 11.

Another embodiment will be described with reference to FIG.

FIG. 6 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. The embodiment shown in FIG. 6 is different from the embodiment shown in FIG.
The fluorescent lamps FL1 and FL2 are connected to each other, and a discharge detection circuit 12 is connected to each of the fluorescent lamps FL1 and FL2.

As a method of controlling the inverter circuit 11, preheating may be controlled simultaneously for the two fluorescent lamps FL1 and FL2, but any one of the fluorescent lamps FL1 and FL2 may be controlled to a state such as end of life. Is generated, control may be performed to stop the output of only the corresponding fluorescent lamps FL1 and FL2. It should be noted that the time setting may be made different for the preheating in accordance with the respective fluorescent lamps FL1 and FL2.

In any of the embodiments, as a method of detecting the discharge, the filament preheating current may be canceled by a transformer or the like, or may be detected by detecting the portion where the filament preheating current does not flow. good. In this case, since the detected value is the amount of discharge, it is effective to detect it by peak detection or the like.

The method of reducing the output of the inverter circuit 11 is not limited to the method of changing the frequency, and the output may be controlled by converting the duty ratio.

[0030]

According to the discharge lamp lighting device of the first aspect, the discharge detection means detects the discharge of the discharge lamp, and when the discharge of the discharge lamp is detected, the output of the discharge lamp lighting means is controlled by the control means. In order to reduce the temperature, the discharge lamp is discharged before it is sufficiently preheated, so that the discharge lamp is prevented from being turned on, the preheating can be appropriately performed, and the life of the fluorescent lamp can be extended.

According to the discharge lamp lighting device of the second aspect,
In addition to the discharge lamp lighting device according to the first aspect, the discharge detection means is not connected to the discharge lamp lighting means in a DC manner. The discharge of the discharge lamp can be detected.

According to the discharge lamp lighting device of the third aspect,
In addition to the discharge lamp lighting device according to claim 1 or 2, the discharge lamp lighting means preheats the filament with the discharge lamp and / or the weak discharge and / or the leakage current, so that it is possible to obtain a little brightness and to be stable. The discharge lamp can be preheated under preheating conditions.

According to the discharge lamp lighting device of the fourth aspect,
Since the discharge detecting means has a filter for removing the lighting frequency of the discharge lamp, by removing the lighting frequency of the discharge lamp with a filter, the influence of the pulsating flow of the lighting frequency is removed, and the discharge lamp is accurately detected with a simple configuration. Discharge can be detected.

According to the illuminating device of the fifth aspect, since there is provided the fixture main body provided with the discharge lamp lighting device of any one of the first to fourth aspects, each effect can be obtained.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view showing the lighting device.

FIG. 3 is an equivalent circuit diagram showing a state in which the fluorescent lamp is not discharged.

FIG. 4 is an equivalent circuit diagram showing a state in which the fluorescent lamp is discharged.

FIG. 5 is an equivalent circuit diagram showing a state where the fluorescent lamp is not mounted.

FIG. 6 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Appliance main body 5 Discharge lamp lighting device 11 Inverter circuit as discharge lamp lighting means 12 Discharge detection circuit as discharge detection means 14 Low pass filter 15 Comparator FL1, FL2 as control means Fluorescent lamp FL1a, FL1b as discharge lamp Filament

Claims (5)

[Claims] 1. A discharge lamp lighting means for lighting a discharge lamp having a filament; a discharge detection means for detecting discharge of the discharge lamp; and an output of the discharge lamp lighting means is reduced when a discharge is detected by the discharge detection means. Control means for preheating the filament by causing the filament to preheat. 2. The discharge lamp lighting device according to claim 1, wherein the discharge detection means is not DC-connected to the discharge lamp lighting means. 3. The discharge lamp lighting device according to claim 1, wherein the discharge lamp lighting means preheats the filament with the discharge lamp and at least one of a weak discharge and a leakage current. 4. The discharge lamp lighting device according to claim 1, wherein the discharge detection means includes a filter for removing a lighting frequency of the discharge lamp. 5. A lighting device, comprising: the discharge lamp lighting device according to claim 1; and a fixture main body provided with the discharge lamp lighting device.