JPS609099A - Device for firing discharge lamp - 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 The present invention relates to a device capable of lighting a plurality of discharge lamps such as fluorescent lamps with different dimming levels.

2. Description of the Related Art Conventionally, a device has been used that uses an inverter to light two annular fluorescent lamps in series at high frequency, which are used for residential lighting. This type of device uses a 32w lamp and a 40w lamp.
Items such as lamps whose rated lamp current is equal to 1
Series lighting was carried out using a stand-alone lighting device. However, since such devices are connected in series, even if lamps with different outer diameters are lit,
It was only possible to insert an impedance into the two lamps and dim them at the same ratio.

In addition, the inventors previously proposed a device as shown in FIG. 1 as a device that can change the dimming degree (attenuation rate) of two lamps. In FIG. 1, (5) is a father current power supply, and (4) is a rectifier circuit for full-wave rectification of this AC power supply (1), which includes a smoothing circuit if necessary. (5) is an inverter that converts the DC power obtained by the rectifier circuit (4) into high-frequency power;
6) is the output transformer of this inverter (5), which is composed of a single cage transformer. (52a)
, (52b) are transistors, (53a), (
53b) is its base resistance, and (51) is a harmonic choke coil that connects one output end of the rectifier circuit (4) with the base resistance (
5+a) and (53b). (
5 is a resonance capacitor connected between the collectors of the transistors (52a) and (52b).

The output transformer (6) has collector windings (6a), (6b
), a feedback winding (6c), and a secondary winding (6S), which constitute an inverter (5). (7) are the first and second windings (7a) and (7b) wound with the same polarity.
).

The input tap (7C) pulled out from the joint of the windings (7a), (7b) and the windings (7a), (7b)
Input taps (7d) with different turns ratios are connected to inverters (
5), a current balancing transformer (hereinafter referred to as a balancer) connected to the output terminal of It is assumed that the discharge lamps (8) and (9) have different rated currents, for example, 40W and 30W for ring-shaped fluorescent lamps. al is a changeover switch, and (10a
) is an all-party contact connected to the balancer (power tap (7C)), (10b) is a dimming contact and connected to the choke coil α
It is connected to the input tap (7d) of the balancer (7) via υ. Although omitted in this figure, a discharge lamp (8
).

The electrode (9) is preheated by a preheating winding provided on the output transformer (6) as required.

In the device configured as described above, the father current power source +
11 is turned on, the inverter (5) switches the feedback winding (
6C), the transistor (52a
) and (52b) alternately open and close, and the output lance (6)
Generates high frequency voltage. At this time, the resonance capacitor (
5 forms a resonant circuit with the inductance of the winding of the transformer (6) and controls the frequency of the impark (5). At this time, if the changeover switch is connected to the all-party contact (10a), this high-frequency voltage will start the discharge lamp (9), then the discharge lamp (8) will start, and the two discharge lamps will start. (81,+
91 is fully lit. That is, the voltage generated in the secondary winding (6S) is applied to the discharge lamp (9) via the winding (7a),
Start the discharge. As a result, voltage is generated in the 1st turn section (7a), and the voltage boosted according to the 2nd turns ratio is transferred to the balancer (7a).
The discharge lamp (8) is started by this voltage. At this time, the discharge lamp (9) has the sum of the discharge current of the discharge lamp (8) and the shunt current that is divided by the balancer (7) and flows through the winding (7a), that is, the secondary winding ( 6S
) output current flows. In addition, the output current of the secondary winding (6S) is connected to the discharge lamp (8) through the winding (7a) of the balancer (7).
9 of the currents that flow in inverse proportion to the turns ratio in (7b)
A shunt current flows through the winding (7b).

Therefore, the output current of the secondary winding (6S) is set to the rated current of the discharge lamp (9), and the current is shunted to the winding (7b).The input tap (
7c), i.e. by setting the turns ratio.

The two discharge lamps (8) and (9) each have their rated current and are lit in the full state.

Here, when the selector switch is switched to the dimming contact (tab) side, the output current is reduced by the choke coil I, and the turn ratio of the balancer (7) changes accordingly, and the number of turns of the second winding (7b) increases. Current flowing through the winding (7b).

In other words, the discharge current of the discharge lamp (8) further decreases, and the two discharge lamps (81, (9) are both dimmed and lit. At this time, the rate of decrease in the discharge current of the discharge lamp (8) is The discharge lamp (9) is also larger, so the dimming rate of the discharge lamp (8) is lower than that of the discharge lamp (8).
9) Yoshi also gets bigger. In this way, this device can be used as a discharge lamp (
Within the range in which the discharge current of (9) is equal to or greater than that of the discharge lamp (8), the dimming rate of each can be freely set.

However, depending on the application, there may be cases where it is desired to increase the dimming rate of the discharge lamp (9) compared to that of the discharge lamp (8). However, the first
In the device shown in the figure, the discharge current of the discharge lamp (9) is as follows.

Since it is not possible to reduce the number of discharge lamps (8), it has not been possible to significantly increase the light attenuation rate of the discharge lamp (9) compared to the discharge lamp (8).

The present invention further improves the above-mentioned drawbacks and is a device that can switch the discharge lamps to increase the dimming rate by switching the discharge lamps between series lighting and parallel lighting.

FIG. 2 is a circuit diagram of a device showing one embodiment of the present invention.
The difference from the device shown in the figure is the configuration of the balancer (71) and the provision of a changeover switch aa for switching the connection of the Jlrk light. ) is connected to one end of the secondary winding (6S), and the output end of the second winding (7b) is connected to the discharge lamp (8).
The output end of the second winding (7a) at one end is connected to the all-light contact (12a) of the changeover switch O2, and the discharge lamp (9).
connected to one end of the The other end of the discharge lamp (8) is connected to the common end of the changeover switch α, and the other end of the discharge lamp (9) is connected to the dimming contact (12b) of the changeover switch α2, and the secondary winding (6S) is connected to the other end.

In the device configured as above, the changeover switch (
When the AC power supply (11) is turned on with the inverter (1'll) connected to the all-party contact (12a), the inverter (5) oscillates in exactly the same manner as the conventional device shown in FIG.

Discharge lamp +81. (91 starts, the rated current flows through each, and all the lights turn on.Next, the changeover switch 0 turns on the dimming contact (
When connected to the 12b) side, the discharge lamp (81e' tc+)
are connected in parallel via a balancer (7). Even in this state, the balancer (7) is inversely proportional to the turns ratio of the windings (7a) and (7b).

The output current of the secondary winding (6S) is shunted. Therefore.

This shunt ratio does not change between full-light lighting and dimming lighting, so the discharge current flowing to the discharge lamp (8) via the 9th winding (7b) is equal to that in the full-light lighting state, and the discharge lamp (8) is y Lights up in full light condition. Only the current that is divided by the balancer (7) and flows through the first winding (7a) flows through the discharge lamp (9) as a discharge current. The current flowing through the winding (7a) of the balancer (7) is
Equivalent to when all lights are on. Therefore, the discharge current of the discharge lamp (9) is the difference between the discharge current when the full light is on and the discharge current of the discharge lamp (8). 8)
Whereas all the lights are on.

The discharge lamp (9) is lit with a large dimming rate.

In this way, the discharge lamp (
The light attenuation rate of (9) can be greatly increased compared to that of discharge lamp (8).

FIG. 3 is a circuit diagram showing another embodiment according to the present invention;
When setting the dimming lighting state, press the selector switch a to turn on the discharge lamp (
By changing the connection status of 8) and (9) and at the same time changing the input tap of the balancer (7) to change the shunting ratio, the discharge current of the discharge lamps (81, (91) can be freely set. That is, the winding (7a) of the balancer (7),
Input tap (7c) to change the turns ratio of (7b).

(7d) is provided, and the changeover switch for switching between the manual taps (7C) and (7d) is synchronized with the changeover switch a2 for changing the connection of the discharge lamps (81, +91).

Note that the input tap (7d) is connected to the contact (10b) of the changeover switch Ql via the choke coil ←υ.

When dimming and lighting, selector switch α1. Q2 is a dimming contact (10
b), when connected to (12b), the discharge lamp +81.
(9) are connected in parallel via the balancer (7), and at the same time the input taps of the balancer (7) are connected from (7C) to (7d).
Changes to

Winding (7a) increases when connected to input tap (7d).

(71)) is the shunt current that decreases and flows through the first winding (7b),
That is, the discharge current of the discharge lamp (8) increases and the shunt current of the second winding (7a) further decreases. By changing the input tap in this way, each discharge lamp +81. (It becomes possible to freely set the reduction rate of C of 91. Also, at this time, the input tap does not necessarily reduce the winding (7b).

(7a) may be used not only in the method of increase but also in the reverse manner. The choke coil tL11 prevents the discharge lamp (8) from overcurrent), and may be connected as necessary to increase the degree of freedom in setting the dimming rate. The sara-trap changeover switch member and the mackerel do not necessarily need to operate in conjunction with each other, and may be configured to operate independently.

In the above embodiment, the case where the discharge lamps (81t (9)) have different rated currents has been described, but the present invention is not limited to this, and the present invention can also be applied to discharge lamps having the same rated current.

Similar effects can be obtained if the full-light lighting shown in FIG. 2 is set to the dimming state of the discharge lamp (8), and the dimmed lighting is set to the dimming state of the discharge lamp (9).

Further, instead of the discharge lamps (81, +91), a series circuit in which a plurality of discharge lamps are connected in series may be connected.

Furthermore, the inverter and rectifier circuit are not limited to those shown in the above embodiments, and may be of any type as long as the discharge lamp can be lit by high-frequency output. It is especially convenient if it shows.

Note that the method of the above embodiment is the simplest method for the changeover switch, but the method is not limited to this.

As described above, the device of the present invention includes a circuit that connects a part of a plurality of discharge lamps connected in series to the output end of a current balancing transformer that shunts the output current of an inverter, and an output of the current balancing transformer. It is possible to switch between the discharge lamp connected to the end and the series circuit of other discharge lamps connected in parallel via the current balancing transformer, allowing freedom in setting the dimming rate of each discharge lamp. It has the advantage of increasing the degree of

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a conventional device, FIG. 2 is a circuit diagram showing one embodiment of the present invention, and FIG. 3 is a circuit diagram showing another embodiment of the present invention. The same symbols in the figures indicate the same or equivalent parts, (1) is an AC power supply, (4) is a rectifier circuit, (5) is an inverter, and (6) is a rectifier circuit.
) is the output transformer, (7) is the current balancing transformer, (6)
, (9) is a discharge lamp, a'IJ is a changeover switch, I
is a choke coil. Agent Masuo Oiwa 6o c-

Claims (3)

[Claims] (1) An inverter that converts DC power to high frequency power,
A current balancing transformer with an input tap connected to one of the output terminals of this inverter and which shunts the output current of the inverter, a discharge lamp connected to both output terminals of this current balancing transformer, and one output of this current balancing transformer. a discharge lamp connected between the terminal end and the other output terminal of the inverter, and a changeover switch for switching the connection of both lamps between separate output terminals of the current balancing transformer and the other output terminal of the inverter. A discharge lamp lighting device comprising: (2) A patent characterized in that a discharge lamp connected between the output terminals of a current balancing transformer has a lower rated current than a discharge lamp connected between the current balancing transformer and the output terminals of an inverter. A discharge lamp lighting device according to claim 1. (3) The discharge lamp lighting device according to claim 1 or 2, wherein the current balancing transformer has a plurality of input taps with different winding ratios and can be selectively switched.