JPH0240895A - discharge lamp lighting device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a discharge lamp lighting device, and particularly to a discharge lamp lighting device for lighting a plurality of discharge lamps.

[Prior art] Conventionally, when lighting multiple discharge lamps such as fluorescent lamps,
The lamps may be connected in series or in parallel.

Here, the parallel lighting type discharge lamp lighting device as shown in FIG. 3 includes two discharge lamps 10.12 and each discharge lamp 10.1.
A cage transformer 14 for supplying a high frequency voltage to 2;
It includes a DC-AC converter 18 that converts the DC voltage supplied from the DC power supply 16 into an AC voltage and applies a high frequency voltage to the primary winding of the one-cage transformer 14.

The high frequency voltage generated on the secondary winding side of the leakage transformer 14 is supplied to each discharge lamp 10.12 via a balancer 20 for applying an appropriate voltage to the discharge lamp 10.12, and discharges and lights up the discharge lamp 10.12. will be carried out.

However, in such a parallel lighting type discharge lamp lighting device, the discharge lamps 10 are connected to each other through the balancer 20 as described above.
．． Since 12 are connected in parallel, there are problems such as an increase in the number of parts, which increases costs, and also takes up space.

Therefore, conventionally, a series lighting type discharge lamp lighting device as shown in FIGS. 4 and 5 is often used.

However, in the device shown in FIG.
2 are connected in series, each discharge lamp must be of the same type and equivalent.

That is, if the lamp currents of the discharge lamps 10 and 12 are not the same, the appropriate temperature of the discharge lamps will not be maintained, which may lead to a decrease in luminous efficiency and deterioration of the phosphor.

On the other hand, FIG. 5 discloses a configuration in which an impedance element (supersaturation reactor) 22 is connected in parallel with the discharge lamp 12 with a small lamp current to form a current bypass path and adjust the current of each lamp.

Therefore, there is an advantage that appropriate usage conditions can be obtained even if the discharge lamps 10, 12 are of different types.

[Problem to be solved by the invention] Stirrup-free person 2 yen■A However, even in such an improved discharge lamp lighting device, an impedance element, etc. is required, resulting in an increase in the number of parts and an increase in cost. There is a problem with that.

Moreover, in the series lighting method, if one discharge lamp is not lit, the other discharge lamp cannot be lit either, so it is difficult to say that it is the best lighting method.Especially with household fluorescent lamps, etc. Since there are many cases where the equipment is not available, there are many inconveniences in the series lighting method in which it is not possible to turn on only the negative lights.

The present invention has been made in view of the problems of the prior art described above, and its purpose is to provide a discharge lamp lighting device that can independently light different types of discharge lamps while suppressing an increase in the number of parts. It is about providing.

[Means for Solving the Problems] In order to achieve the above object, a discharge lamp lighting device according to the present invention comprises an output transformer including a negative primary winding and a plurality of secondary windings having different numbers of turns, The device is characterized in that a discharge lamp with a different power rating and a switch element are connected in series to each secondary winding.

[Function] Since the discharge lamp lighting device according to the present invention has the above-described means, a high frequency voltage corresponding to the number of turns of each secondary winding can be obtained in each secondary winding.

Therefore, by connecting discharge lamps corresponding to each voltage, an appropriate discharge lamp lighting state can be obtained.

Furthermore, since each discharge lamp receives lamp current from its own independent secondary winding, it can be turned on and off independently.

Therefore, the switch element connected in series to each discharge lamp is set to 0.
By performing N-OFF control, discharge lamps having different rated currents can be turned on and off independently.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a circuit configuration diagram of a discharge lamp lighting device according to an embodiment of the present invention, and portions corresponding to those in the prior art are indicated by the reference numeral 100, and their explanation will be omitted.

A characteristic feature of the present invention is that a plurality of discharge lamps with different rated powers can be turned on and off independently, and for this reason, in this embodiment, the leakage transformer 114 is equipped with a so-called E-shape. It uses a transformer using "Core".

Here, a transformer using a cross-shaped core has one primary coil 114a and at least two secondary coils 114b and 114C in the inner core, as shown in detail in Japanese Patent Laid-Open No. 59-40500. An outer core having magnetic legs that are wound around each other and forming a leakage magnetic path between the respective coils is arranged so as to surround each of the coils, thereby forming a one-cage transformer.

In this embodiment, the leakage transformer 1
The number of turns of the No. 14 secondary winding 114b is larger than that of the secondary winding 114c.
The discharge lamp 110 connected to the terminal b is made of, for example, a 32W fluorescent lamp, and the discharge lamp 110 connected to the secondary winding 114c
2 is, for example, a 30W fluorescent lamp.

Further, each fluorescent lamp 110, 112 has a switch element 1.
30 and 132 are connected in series.

In this embodiment, each switch element 130, 132 is
In order to prevent a cold cathode discharge state, a soft start switch including a semiconductor switching element as shown enlarged in FIG. 2 is used.

That is, the switching element 132 includes a semiconductor switching element 140 made of a triac, and a semiconductor switching element 140 made of a triac.
and a transistor 142 whose emitter end is connected to the gate electrode of 40.

A series circuit consisting of a diode 146, a resistor 148, and a capacitor 150 is connected to the preheating winding 144a.
54 series circuits are connected in parallel.

Furthermore, the connection point between the resistor 148 and the capacitor 150 is connected to the collector end of the transistor 142 via a resistor 156, and the connection point between the resistor 152 and the capacitor 150 is
The connection point 54 is connected to the base end of the transistor 142 via a Zener diode 158.

Note that although the switching element 132 has been described in FIG. 2, the switching element 130 is also configured in the same manner.

Next, the operation of the discharge lamp lighting device according to this embodiment will be explained.

First, when the DC power supply 116 is turned on, the DC-AC converter 118 converts the DC to AC, and the leakage transformer 1
A high frequency voltage is generated in each of the 14 windings.

Here, preheating windings 144a, 144b, 144c, 14
The voltage generated at 4d immediately begins to warm each electrode of the discharge lamps 110 and 112.

However, since the switching elements 130 and 132 (TRIAC 140) are still in the OFF state at this point, the voltage generated in the secondary windings 114b and 114c is
, 112, and no discharge occurs.

During this time, the voltage generated in the preheating winding 144a is rectified and smoothed by the diode 146, the resistor 148, and the capacitor 150, and a DC voltage is generated in the capacitor 154. This DC voltage causes the capacitor 154 to be connected to the resistor 152.
The battery is charged while the current is limited, and the voltage gradually increases. When the voltage of the capacitor 154 increases to the Zener voltage of the Zener diode 158, the transistor 14
A voltage is applied to the base terminal of the transistor 142, and the transistor 142 is turned on.

Then, the voltage of the capacitor 150 supplies a current to the gate electrode of the triac 140 via the resistor 156 and the transistor 142, and the triac 140 is turned on.

Once turned on, the triac 140 is constantly supplied with gate current, so it remains on until the power is turned off.

When the triac 140 turns ON, the secondary winding 114
The voltage generated at lamps 110 and 114b and 114c
2 and each lamp 110, 112 starts discharging.

By this time, the electrodes are already in the preheating winding 144a.

Since the lamps are sufficiently heated by the lamps 144b, 144c, and 144d, cold cathode discharge does not occur, and electrode consumption and lamp blackening can be prevented.

Thus, according to this embodiment, each lamp 110.11
By adjusting the time constants of the capacitors of the switch elements 130 and 132 according to the characteristics of the lamps 110 and 112, it is possible to set the optimal discharge start timing for each lamp 110, 112.

When discharge starts in each lamp 110, 112, each secondary winding 114b, 114c is connected to each lamp.
A high frequency voltage corresponding to the number of turns is applied, and the characteristics of each lamp are fully exhibited.

As described above, according to the discharge lamp lighting device according to this embodiment, a plurality of discharge lamps of different types can be lit independently and under optimal conditions.

Furthermore, even if one lamp is removed, for example, the lighting of the other discharge lamp will not be affected in any way.

In this embodiment, each switch element is an example in which a soft start switch is used, but for example, a manual ON-O switch is connected in series with the soft start switch.
It is also preferable to connect an FF switch so that only one of the discharge lamps can be turned on at will.

[Effects of the Invention] As explained above, according to the discharge lamp lighting device according to the present invention, the output transformer is configured with a negative primary winding and a plurality of secondary windings with different numbers of turns, and each secondary winding is Since discharge lamps with different rated powers are connected in series to the line, it is possible to turn on and off multiple types of discharge lamps independently.

Further, by using a semiconductor switching element that is non-conductive for a certain period of time at startup as a switching element connected in series to each discharge lamp, it becomes possible to light a plurality of types of discharge lamps in each optimal state.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a discharge lamp lighting device according to an embodiment of the present invention, Fig. 2 is a detailed explanatory diagram of the switch element portion of the device shown in Fig. 1, and Fig. 3 is a conventional parallel Figure 4 is a circuit diagram of a discharge lamp lighting device using a lighting method. Figure 4 is a circuit diagram of a conventional discharge lamp lighting device using a series lighting method. Figure 5 is a circuit diagram of another conventional discharge lamp lighting device using a series lighting method. It is. Figure 1 10゜14゜16゜18゜130゜12, 110゜114 ... 116 ... 118 ... 132 ... 112 ... Discharge lamp - cage transformer DC power supply DC-AC converter switch element

Claims (2)

[Claims] (1) A DC-AC converter that converts direct current to alternating current, and the D
In a discharge lamp lighting device including an output transformer that takes out the output of a C-AC converter, and a discharge lamp that is powered by the output transformer and is lit, the output transformer has one primary winding having a different number of turns. 1. A discharge lamp lighting device comprising a leakage transformer having a plurality of secondary windings, each of which is connected in series with a discharge lamp having a different rated power. (2) The device according to claim 1, wherein each discharge lamp and a switch element are connected in series, the switch element including a semiconductor switching element connected in series with each secondary winding, and starting the semiconductor switching element. A discharge lamp lighting device characterized by being in a non-conducting state for a certain period of time.