JPH0696737A - High pressure discharge lamp - Google Patents

Abstract

PURPOSE:To provide a high pressure discharge lamp, which can be re-started instantaneously. CONSTITUTION:An electronic starting circuit 20, which utilizes an external mercury lamp stabilizer 22 to selectively light up light emitting tubes 3a, 3b and which is operated at a voltage higher than the lamp operating voltage and in which a non-linear capacitor 17 and a two-way thyristor 18 are connected in series, is provided inside of a base 2 of an external tube 1a. In the case where one light emitting tube becomes hard to emit the light, the other light emitting tube is re-started instantaneously with the operation of this electronic starting circuit 20 independently of the heat of the light emitting tubes 3a, 3b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high pressure discharge lamp in which a plurality of arc tubes are housed in an outer tube and one of them is lit.

[0002]

2. Description of the Related Art In a high-pressure metal vapor discharge lamp such as a high-pressure sodium lamp or a metal halide lamp, the internal pressure of the arc tube becomes 1 atm or more during lighting, so when restarting after turning off the lamp, the arc tube cools down to some extent. It is necessary to wait until the internal pressure drops below a predetermined level due to the aggregation of mercury and the enclosed luminescent metal. For example, in the case of a high pressure sodium lamp, the restart time is about 1 minute, and in the case of a metal halide lamp it is 10 minutes.
You have to wait more than a minute, and even after restarting, you have to wait a few more minutes before the stable lighting state is reached.

Therefore, for example, when there is a momentary power failure, in the case of an incandescent light bulb or a fluorescent lamp, the lamp is immediately turned on, but in the case of the above high-pressure metal vapor discharge lamp, it is necessary to wait for 10 minutes or more before the full power is exerted. This is inconvenient when used for road lighting, tunnel lighting, etc.

In order to improve this, USP 4,287,
No. 454 discloses that two arc tubes are housed in an outer tube,
A high-pressure sodium lamp has been proposed in which these arc tubes are electrically connected in parallel and one of the arc tubes is turned on.

By the way, such a high-pressure sodium lamp is started by using a heat-responsive switch so that the ballast a used for lighting a mercury lamp can be used as it is for lighting as shown in FIG. It has a built-in circuit e. In many cases, a structure that takes into account the heat of the arc tubes h and h during lighting is used.

[0006] Specifically, the starting circuit e is a starting circuit e in which a normally closed thermal response switch c (bimetal switch or the like) and a current limiting resistance d (heater) are connected in series to a lamp b.
And a starting circuit e for each contact point f, g of the base.
And a structure in which two arc tubes h, h connected in parallel are connected in parallel.

That is, in the high-pressure sodium lamp, a lighting circuit is constructed by utilizing a combination of a starting circuit e inside the lamp and an inexpensive mercury lamp ballast a outside the lamp. However, j is an electrode of the arc tube h, and k is an adjacent conductor.

With this lighting circuit, at the time of starting the lamp, the current limiting resistance d is heated by the energization from the AC power source i, and the heat responsive switch c is opened by this heat, and the kick voltage pulse generated at this time is stabilized. By superimposing it on the AC power supply voltage of a, either of the arc tubes h and h is started with a probability of 50%. After that, the thermal switch c
Remains open due to heat from the arc tubes h, h.

[0009]

However, according to the starting circuit e using such a normally closed thermal response switch c, the thermal response switch c continues to be in the open state due to the lamp heat during the lamp lighting. However, even if one of the arc tubes h becomes difficult to light up and the other arc tube h is immediately started, that is, a situation where a momentary restart is desired, the heat-responsive switch c is instantaneously operated.
Does not recover. Specifically, it may be necessary to wait for about 10 minutes until the heat-actuated switch c returns, and there is an inconvenience that the demand for the situation where the lamp is installed cannot be met.

The present invention has been made in view of such circumstances, and an object thereof is to provide a high pressure discharge lamp capable of instantaneous restart.

[0011]

In order to achieve the above object, a high pressure discharge lamp according to claim 1 comprises an outer tube having a base,
A plurality of arc tubes housed in the outer tube, a lighting control unit for selectively lighting the arc tube, and connected to the arc tube,
And an electronic starting circuit that operates at a voltage higher than the lamp operating voltage of the arc tube.

According to another aspect of the high pressure discharge lamp of the present invention, an outer tube having a base, a plurality of arc tubes housed in the outer tube, and a plurality of arc tubes respectively attached to the arc tubes are energized with different potentials. And an electronic starting circuit which is connected to the arc tube and operates at a voltage higher than the lamp operating voltage of the arc tube.

In a high pressure discharge lamp according to a third aspect of the present invention, in order to start the arc tube with a simple structure, the electronic starting circuit according to the first or second aspect is a series circuit of a non-linear capacitor and a bidirectional thyristor. It consists of.

[0014]

According to the high pressure discharge lamp of the present invention, when the lamp is started, the electronic starting circuit operates at a voltage higher than the lamp operating voltage, and cooperates with the lighting control unit to start one of the arc tubes. . After starting, the electronic starting circuit is deactivated.

In this case, one of the arc tubes falls into difficulty in lighting,
Even if it is desired to instantly restart the other arc tube, the operating voltage of the electronic starting circuit is higher than the lamp voltage, so that the starting operation is instantaneously performed.

According to the high-pressure discharge lamp of the second aspect, at the time of starting the lamp, the electronic starting circuit operates at a voltage higher than the lamp operating voltage, and cooperates with the starting proximity conductor to start one of the arc tubes. Let After starting, the electronic starting circuit is deactivated.

Here, one of the arc tubes is difficult to light,
Even if it is desired to instantly restart the other arc tube immediately, as in the case of claim 1, the operating voltage of the electronic starting circuit is higher than the lamp voltage, so that the starting operation is instantaneously started.

According to the third aspect of the high pressure discharge lamp, when the lamp is started, one of the arc tubes is started with a uniform probability by a pulse generated by the non-linear capacitor and having a voltage higher than the lamp operating voltage.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in FIGS.

FIG. 2 shows a cross section of a high pressure discharge lamp to which the present invention is applied, and FIG. 1 shows a lighting circuit of the high pressure discharge lamp.

In FIG. 2, reference numeral 1 is a high pressure sodium lamp (high pressure discharge lamp) having a rated input of 360 W, and 1 a is an outer tube of the high pressure sodium lamp 1. The outer tube 1a is made of hard glass or the like and has a substantially straight tube shape. A base 2 is attached to one end of the outer tube 1a.

In the outer tube 1a, two arc tubes 3a, 3
b is accommodated. In these arc tubes 3a and 3b, an end plate made of a ceramic disk is hermetically joined to an end portion of a bulb made of a ceramic tube such as polycrystalline alumina or single crystal alumina as a closing wall, and an electrode 4 is attached to these end plates. Sealed with ...
Each electrode 4 is constructed by winding a coil portion 4a around an electrode shaft, and a conductive structure 5 connected to the electrode 4 ...
Is projected from the end plate to the outside, and sodium, mercury and xenon gas are sealed in the arc tubes 3a and 3b.

The luminous tubes 3a, 3a are arranged in parallel with the axis of the outer tube 1.

The stem 7 of the outer tube 1 is connected with support wires 8a and 8b (made of, for example, conductive wires) extending upward from the side of the stem 7 along both sides of the arc tubes 3a and 3b. Specifically, the lower ends of the support wires 8a and 8b are welded to the sealing support wires 9a and 9b sealed to the stem 7. Between the upper side and the lower side of these support wires 8a and 8b, there is a valve support plate 11 made of a member having excellent heat resistance such as ceramics.
a and 11b are fixed.

These valve support plates 11a and 11b
The upper and lower conductive structures 5 of the arc tubes 3a and 3b are fixed by penetrating the arc tubes 5a and 5a.
It is supported at a predetermined position inside.

Further, each valve support plate 11a, 11b
The conductive structure 5 that penetrates through the connection wires 12a, 1 made of a heat-resistant metal such as niobium or tantalum is provided on each of the upper and lower sides.
2b are connected to each other.

The connecting wires 12a and 12b are connected to the support wires 8a and 8b, and the sealing support wire 9 is formed.
The base 2 is electrically connected via a and 9b. For more information,
Each sealing support wire 9a, 9b is connected to the shell 2a of the base 2 and the eyelet terminal 2b via an external conductor 13a, 13b so that an alternating voltage can be received from the outside through the base 2.

Supports adjacent to the arc tubes 3a and 3b are also provided.
The close wires 1a and 8b are located near the electrodes 4 having polarities different from those of the support wires 8a and 8b.
4a, 14b (starting aids) are provided to give discharge starting characteristics of different polarities to the respective arc tubes 3a, 3b.

A heat reflecting plate 23 supported by support wires 8a and 8b is provided between the lower valve support plate 11b and the stem 7 so as to shield the two, and heat is applied to the base. It suppresses the incident on the side.

On the other hand, an electronic starter 15 is built in the base 2. The electronic starter 15 has various elements mounted on a circuit board 16 having a hole (not shown) formed in the center.

More specifically, the substrate 16 is disposed in the space inside the base 2 with the hole penetrating the exhaust pipe 7a of the stem 7, and is fixed to the same portion in this state. A non-linear capacitor 17, a bidirectional thyristor 18, and a resistor 19 are mounted on the board 16.

As shown in FIG. 1, the bidirectional thyristor 18 and the resistor 19 are connected in parallel. A non-linear capacitor-17 is connected in series to this parallel circuit. The circuit including the non-linear capacitor 17, the bidirectional thyristor 18 and the resistor 19 is connected in parallel to the arc tubes 3a and 3b, and constitutes an electronic starting circuit 20. The electronic starting circuit 20 is set to operate at a voltage higher than the lamp operating voltage. Specifically, when the base 2 is attached to a socket (not shown), the electronic starter circuit 20 uses an externally installed lighting control unit, for example, a 400 W mercury lamp ballast 22 that is a phase delay type by a capacitor 22a to exchange an alternating current. Conducts electricity with the power supply 21. And
By combination with the lag type ballast 22, for example, a high-voltage pulse, for example, a high-voltage pulse of about 2500 V, for example, is superimposed on a sine wave as shown in FIG. 3b is selectively turned on.

However, in FIG. 2, 24 is the support wire 8
Getters 25 provided on the lower side of a and 8b are ceramic insulators which form the base 2 as an insulating portion.

Next, the operation of the high pressure sodium lamp 1 thus constructed will be described.

The high pressure sodium lamp 1 is attached to a socket (not shown). By this mounting, the arc tubes 3a and 3b and the electronic starting circuit 20 built in the lamp 1 are electrically connected to an external mercury lamp ballast 22.

Thereafter, a power switch (not shown) is turned on to start the high pressure sodium lamp 1.

Then, as shown in FIG. 3, a high-voltage pulse P of about 2500 V generated from the non-linear capacitor 17 is superposed every half cycle of the AC power supply voltage V.

At this time, since the polarity of the high-voltage pulse P is inverted with a probability of 50%, one of the arc tubes 3a and 3b is started with an equal probability, that is, a probability of 50%. This is because different potentials are applied to the adjacent conductors 14a and 14b.

After the start, the high-voltage pulse P is not generated from the non-linear capacitor 17, and the light emission of the arc tube is maintained at a predetermined lamp voltage.

If, during lighting, this arc tube becomes difficult to light and it is desired to immediately restart the other arc tube, a high voltage pulse P higher than the lamp voltage is immediately generated from the non-linear capacitor-17. Therefore, the other arc tube is immediately started without being affected by the voltage rise of the AC power supply 21.

Therefore, an electronic starter with a built-in lamp is provided.
Due to 15, the high-pressure sodium lamp 1 can be instantly restarted while using the external ballast 22 and without being affected by the heat of the arc tubes 3a and 3b.

Moreover, the electronic starter 15 is a circuit in which the non-linear capacitor 17 and the bidirectional thyristor 18 are combined in series, so that the structure is simple.

Since the heat reflecting plate 23 is provided so that heat does not enter the side of the base 2, the temperature of the base 2 can be lowered during lighting, so that a sufficient pulse height can be secured. .

Although the present invention is applied to the high-pressure sodium lamp, it goes without saying that it may be applied to other high-pressure discharge lamps.

[0045]

As described above, according to the invention described in claims 1 to 3, it is possible to provide a high pressure discharge lamp capable of instantaneous restart.

According to the third aspect of the invention, in addition to this, the configuration of the electronic starting circuit is simple.

[Brief description of drawings]

FIG. 1 is a diagram showing a lighting circuit of a high-pressure sodium lamp according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the structure of the high-pressure sodium lamp of the same embodiment.

FIG. 3 is a diagram showing an AC power supply voltage on which a high-voltage pulse from the non-linear capacitor of the same embodiment is superimposed.

FIG. 4 is a diagram showing a starting circuit of a conventional high pressure sodium lamp using a heat-responsive switch.

[Explanation of symbols]

1a ... Outer tube 3a, 3b ... Arc tube 14a,
14b ... Proximity conductor for starting 15 ... Electronic starter 17 ... Non-linear capacitor-18 ... Amphoteric thyristor-20 ... Electronic starting circuit
22 ... Late type ballast

Claims (3)

[Claims] 1. An outer tube having a base, a plurality of arc tubes housed in the outer tube, a lighting control unit for selectively lighting the arc tube, and a light emitting tube connected to the arc tube for emitting light. A high pressure discharge lamp comprising an electronic starting circuit that operates at a voltage higher than the lamp operating voltage of the tube. 2. An outer tube having a base, a plurality of arc tubes housed in the outer tube, a starting proximity conductor attached to each of the arc tubes and biasing different potentials from each other. A high-pressure discharge lamp, comprising: an electronic starting circuit connected to the arc tube and operating at a voltage higher than a lamp operating voltage of the arc tube. 3. The high pressure discharge lamp according to claim 1, wherein the starting circuit comprises a series circuit of a non-linear capacitor and a bidirectional thyristor.