JPS59163799A - 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 discharge lamp lighting device that can easily change the dimming degree of a plurality of discharge lamps lit in series using a frequency.

2. Description of the Related Art Conventionally, there is a discharge lamp lighting device shown in FIG. 1 that dims and lights a plurality of discharge lamps connected in series.

In the figure, (1) is an AC power supply, (2) is a full-wave rectifier circuit that performs full-wave rectification of the AC power supply, and (3) is an inverter.

The DC output obtained from the full-wave rectifier circuit (2) is converted into high-frequency power.

The inverter (3) is equipped with a high frequency choke (4) connected to the full-wave rectifier circuit (2), and includes a pair of transistors (51i61 and a front transistor (51, ()).
It consists of a resistor (7L T8) connected to the base of 61, an output transformer (9) as a leakage transformer, and a resonance capacitor aα connected to the output transformer (9).

Furthermore, the output transformer (9) is a transistor (5).
.

A feedback winding OD connected to the base of the transistor (6), a pair of collector windings ab and a'a connected to the collector of the transistor (5) and (61), and a high voltage It consists of a secondary winding (141) that generates a high frequency voltage.

Reference numeral 151 denotes a changeover switch, which is connected to one end of the secondary winding - of the output transformer (9). The front self-off switch 05) is the all-purpose contact (161) and the dimming contact (161).
711, the front d pin full-light contact t161 is connected to the electric power connected to the discharge lamp 4, such as an annular fluorescent lamp, and the dimming contact σ is connected to the discharge lamp ttS through the inductor 091.
A discharge lamp such as a ring-shaped fluorescent rung connected in series with +
It is electrically conductive. The front 6-pin inductor (19) consists of a first winding qυ and a second winding, and is connected to the changeover switch 0.
5) Input tag connected to dimming contact f171■
It is equipped with

Here, when the AC power source (1) is turned on with the changeover switch 05) connected to the all-party contact 4161, the inverter (3) is turned on by the action of the feedback winding (Ill) of the output transformer (9). Self-excited oscillation is started as shown below, and a high frequency voltage is generated in each winding of the output transformer (9).Then,
The high frequency voltage is applied to the all-party contact 161 of the changeover switch α9.
and the inductor is connected to the first winding Cυ and the second winding Cυ of
The voltage is applied to the discharge lamp (support) through the winding (2), so
First, the lantern lights are lit. At this time, since a discharge current flows through the inductor (191), a high frequency voltage is generated across the inductor (191), and the discharge lamp (18
), the discharge lamp - is turned on one after another.

In this way, discharge lamp ti81. (4)) is fully lit.

Next, when the changeover switch Q51 is connected to the dimming contact (I7), the frequency voltage generated in the secondary winding α4 of the output transformer (9) passes through the dimming contact αη, and the input tap CD of the inductor σ9). and the discharge lamp cgl through the second winding ■
c is applied, the discharge lamp (4) discharges first. In this case, the discharge current (Ial flows through the second winding of the inductor (19), so the high frequency voltage is boosted by the action of the inductor (19) and the first winding QI
Since it is applied to the discharge lamp from I, the discharge lamp is lit one after another, and a discharge 'magnetic current (Ibl) flows.Here, the discharge current flowing to the discharge lamp (4) is (Ial and +I).
By appropriately setting the first winding law of the inductor 09) and the turn ratio of the second winding @, the threat current becomes the threat current of bl. It becomes possible to set the current value to 50% and enter the dimming state.

In addition, if the inverter (3) exhibits almost constant current characteristics against slight changes in load impedance, it will be advantageous, and the output current of the inverter (3) will flow through the discharge lamp, and the output current will be almost constant. Illuminated in light condition.

In addition, when the inverter (3) does not have constant current characteristics, the discharge lamp is also dimmed, but the dimming level is shallower than that of the discharge lamp (I role). However, in any case, the discharge lamp ( When the dimming level of the first lamp is deep and the discharge lamp is about to go out, the voltage induced in the first winding 1l of the inductor t191 acts in the direction of increasing due to the withdrawal part fIblK, and the discharge lamp 081 becomes stable. Maintain dimming status.

However, in such a discharge lamp lighting device,
A discharge lamp (181) with an inductor [19] connected in parallel
The dimming of the discharge lamp (support) to which the inductor (19) is not connected cannot be dimmed deeply.

Depending on the application, it is extremely inconvenient if you want to deeply dim both the discharge lamp +181 and (4)), and the discharge lamp (181, f20+ is lit in series, so the discharge lamp starts discharging first). There is a problem that if J) is not lit, both lights cannot be lit.

This invention has been made in view of the above-mentioned problem, and involves switching the dimming state of a plurality of discharge lamps lit in series using a changeover switch, and connecting the plurality of discharge lamps in parallel to an inductor. It is an object of the present invention to solve the above-mentioned conventional problems by providing a discharge lamp lighting device capable of deeply dimming all of the plurality of discharge lamps.

Examples of the present invention will be described below.

Note that the same reference numerals are given to the same or corresponding parts as in the conventional example.

FIGS. 2 and 3 show an embodiment of the present invention, in which a discharge lamp changeover switch (a) is composed of a pair of interlocking switches (to) and (25+), each having a contact point (a).

■ is the power connected to the discharge lamp usha, contact 0.0 is the discharge lamp ■
It is connected to. The terminal (2) of the front 6 switch (to) is connected to the all-party contact Oθ of the changeover switch 09 and the inductor 09), and the terminal [F] of the switch (c) is connected to the inverter (3).

Here, connect the discharge lamp changeover switch (c) to contact (A), 03
) side, the discharge lamp - as shown in Figure 3 (A).
is connected in parallel with inductor 4 to achieve a deep dimming state, and when the contact (Q) is switched to the 0 side, this time, as shown in Figure 3 (b)
As shown in the figure, the discharge lamp is connected in parallel to the inductor circuit, resulting in a deep dimming state.

Further, as described above, the connection of the discharge lamps 118) and 118) are lit in series by switching the connection of the discharge lamps 118) by operating the discharge lamp changeover switch f231.

0 groups of discharge lamps (or 4 discharge lamps) are discharged first during harvesting.
)) does not discharge due to its lifespan, etc., the other discharge lamp f
20+ (or discharge lamp 08111't: It is possible to switch to normal discharge embossing (or discharge lamp t18+1).

@4 Figure shows another embodiment.

In the figure, 121i) is a choke coil as a dimming impedance. Note that each arrow indicates a connection to a discharge lamp changeover switch (231 (not shown)).

This discharge lamp lighting device further includes all discharge lamps 081. (support)
) to dim the discharge lamp t181 (or discharge lamp (4) In addition, the inductor'y (19
1 input tap (when connected to the sword, its choke coil group) reduces the high frequency current, so the total discharge lamp t1
81, (2)) was dimmed.

Furthermore, when the discharge lamp changeover switch is changed, the discharge lamp aa
Since it is possible to control the dimming of all discharge lamps (2o+) and (2o+), it is possible to control the dimming of all discharge lamps (2o+) freely and over a wide range.

FIG. 5 shows yet another embodiment.

In the figure, @ is turned on by the starting circuit that controls the changeover switch (15), and after turning on the AC power supply (1), the inverter (
From the time when the high frequency is generated in step 3) until the start of the discharge lamp U&, (201) is completed, the selector switch 151 is forcibly connected to the dimming contact 07)K. Here, regarding the setting of the end of the front 6-piston start, even if it is for a limited time, it is also possible to
, (4)) The starting may be completed by detecting various quantities such as light emission accompanying the starting.

In the above embodiment, the case where two discharge lamps u8) and (a)) are lit in series is shown, but when three or more lamps are lit in series -8
Of course, it can also be applied to . For example, in the case of lighting three lamps in series, if two of the three lamps are to be lit in deep dimming mode, instead of discontinuing the discharge as shown in Figure 1, arrange the two discharge lamps in series or in parallel. By doing so, you can easily control the lighting.

Furthermore, needless to say, the inverter (3), full-wave rectifier circuit (2), etc. are not limited to those shown in the embodiment.

In addition, a phase shifter amplifier circuit or the like may be provided between the AC power source (1) and the full-wave difference circuit (2) to further perform dimming.

As explained above, according to the present invention, the configuration includes an inverter driven by DC power.

an inductor with an input tap connected in parallel to a part of a plurality of discharge lamps that are lit in series by the output of the inverter; In a discharge lamp lighting device that lights a part of the discharge lamp in a deep adjustment L, the inductor is provided with a discharge lamp changeover switch so that the front V pin inductor can be connected in parallel to any discharge lamp among the plurality of discharge lamps. west.

Since the discharge lamp lighting device is characterized by lighting any discharge lamp with deep dimming, the discharge lamp selection switch can be changed according to the situation to provide the desired discharge lamp with the power that allows deep A light to be turned on. Even if some of the discharge lamps go out due to lifespan or other reasons, they can be switched to other normal discharge lamps and turned on, making it possible to easily prevent all the discharge lamps from going out as in the past. be effective.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a conventional discharge lamp lighting device. FIG. 2 is a circuit diagram showing a discharge lamp lighting device according to the present invention;
FIGS. 3(-r) and ((b) are circuit diagrams explaining the states of the discharge lamp changeover switch shown in FIG. 2, FIG. 4 is a circuit diagram showing another embodiment of the present invention, and FIG. It is a circuit diagram showing still another embodiment. (2)...Full-wave rectifier circuit, @...Discharge lamp changeover switch. (3)...Inverter, ke)...Input tag, (
181, t20+...Discharge lamp, a9)...Inda,
Kuta. Agent Shin Kuzuno - Figure 3 (a) (mouth)

Claims (1)

[Claims] An inverter driven by DC power and an inductor with an input cathode connected in parallel to some of the discharge lamps that are lit in series with the output of the inverter, In a discharge lamp lighting device that performs deep dimming lighting on some of the discharge lamps having a front 6-pin frequency by supplying an output from an inverter, a discharge lamp changeover switch is provided in the inductor to select one of the discharge lamps among the plurality of discharge lamps. A discharge lamp lighting device characterized in that a front T-pin inductor can be connected in parallel to the discharge lamps, and any discharge lamp can be lit with deep dimming.