JPH0554864A - High pressure metal vapor discharge lamp and high pressure metal vapor discharge lamp device - Google Patents

Abstract

PURPOSE:To provide a high pressure metal vapor discharge lamp having simple constitution while being able to be small-sized and to instantly obtain a high light flux. CONSTITUTION:A luminous tube 10 is housed inside an outer tube 1 consisting of a translucent airtight container, a pair of electrodes 12 are sealed inside in this luminous tube 10, a luminous metal and rare gas are sealed and rare gas which emits light by discharge is sealed inside outer tube 1. A pair of discharge electrodes 9 for starting, which generate discharge inside an outer tube due to the rare gas being conducted at a starting time are provided inside this outer tube 1. The electrodes inside the luminous tube and the discharge electrodes for starting inside the outer tube simultaneously discharge at the starting time of the lamp so as to simultaneously start luminescence inside the luminous tube and inside the outer tube so as to be able to make up for the deficiency in quantity of light of the luminous tube with luminescence by discharge inside the outer tube.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high pressure metal vapor discharge lamp and a high pressure metal vapor discharge lamp device such as a metal halide lamp having improved starting characteristics.

[0002]

2. Description of the Related Art Since metal halide lamps are discharge lamps of high efficiency and high color rendering property, they have been conventionally used for wide area lighting such as roads, plazas, stadiums, etc. , Is also being used in projectors and other projectors. However, the metal halide lamp is not one in which a steady luminous flux is instantaneously obtained by turning on the power supply voltage, and it takes a predetermined time for the luminous flux to rise at the time of starting.

That is, in a metal halide lamp, a metal halide, mercury and a rare gas are enclosed in an arc tube. However, since the temperature is low when the lamp is turned off, the metal halide and mercury are aggregated in the coldest part and solidified. It is in the shape of. Therefore, when a starting voltage is applied between the electrodes to generate a discharge and the arc tube bulb is warmed by the heat of this discharge, the solid enclosed metal is gradually heated and evaporated. Then, this metal vapor is ionized and excited by the discharge, and emits light.

Therefore, there is a drawback that it takes several minutes from the time of switch-on to the time of obtaining the total luminous flux in a steady state, that is, the starting rise time is long, and the use is limited because of such characteristics. There is a defect.

In order to improve such starting characteristics,
For example, as shown in Japanese Utility Model Application Laid-Open No. 62-67460, there has been proposed a means for arranging an electric heater in parallel with the arc tube of a metal halide lamp.

In this device, the electric heater is pre-energized before heating to heat the arc tube to heat the arc heater, so that the enclosed metal is evaporated and the vapor pressure is increased in the arc tube. When the discharge is started between the electrodes of the arc tube, the already-evaporated luminescent metal is instantly ionized and excited to emit light, so that the total luminous flux can be obtained in a short time.

[0007]

However, in the case of the structure in which an electric heater is provided in the vicinity of the arc tube as in the above-mentioned conventional case, an electric heater separate from the arc tube is required, so that the number of parts is increased and the assembly is improved. It requires time and effort, and when it is housed in the outer tube, it is necessary to make the outer tube large, which makes it impossible to downsize the lamp.

[0008] Further, in this device, when the lamp is not turned on, the electric heater is energized to heat the arc tube to heat the arc tube, so that the energization loss is large and the overall luminous efficiency is reduced. There is a drawback to

When the lamp is turned on, the electric heater is energized to generate heat so that the arc tube is heated by the heat from the electric heater in parallel with the temperature rise due to the discharge of the arc tube. Although the start-up time is shortened as compared with those not using it, it still requires a certain start-up time and instantaneous lighting is impossible.

The present invention has been made in view of the above circumstances, and an object thereof is a high-pressure metal vapor discharge lamp and a high-pressure metal vapor discharge lamp which are simple in structure, can be downsized, and can instantaneously obtain a high luminous flux. It is intended to provide a metal vapor discharge lamp device.

[0011]

In order to achieve the above-mentioned object, the high-pressure metal vapor discharge lamp of the present invention has a light-emitting tube housed in an outer tube formed of a translucent airtight container, and a pair of light-emitting tubes is housed in the light-emitting tube. The electrodes are sealed, and the arc tube is filled with a luminescent metal and a rare gas, and the outer tube is filled with a rare gas that emits light by electric discharge. It is characterized in that a pair of starting discharge electrodes for generating a discharge in the tube are provided.

Further, the high-pressure metal vapor discharge lamp device of the present invention has a light-emitting tube housed in an outer tube formed of a translucent airtight container,
The arc tube is sealed with a pair of electrodes, the arc tube is filled with a luminescent metal and a rare gas, and the outer tube is filled with a rare gas which emits light by electric discharge. And a high-pressure metal vapor discharge lamp provided with a pair of starting discharge electrodes for generating discharge in the outer tube by the rare gas, and a voltage is applied to the electrodes in the arc tube and the starting discharge electrode in the outer tube at the time of starting to emit these lights. A lighting circuit device is provided, which generates discharges in the tube and the outer tube, respectively, and when a predetermined luminous flux is reached, stops energization to the starting discharge electrode in the outer tube and controls only the discharge in the arc tube to be maintained. It is characterized by

[0013]

According to the present invention, at the time of starting the lamp, a voltage is applied to the electrode in the arc tube and the starting discharge electrode in the outer tube to generate discharges in the arc tube and the outer tube, respectively.
As a result, light emission starts simultaneously in the arc tube and the outer tube, and at this time, even if the light emission amount of the arc tube is small, the light emission due to the discharge in the outer tube is supplemented, so that a predetermined luminous flux can be obtained instantly from the switch-on. When the temperature inside the arc tube rises and the vapor pressure of the enclosed metal increases while the discharge in the outer tube continues, the luminous flux of the arc tube becomes close to the total luminous flux. A predetermined amount of light can be maintained only by the discharge of No. 2, so that unnecessary discharge is eliminated and conduction loss is eliminated.

[0014]

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

FIG. 1 shows a small metal halide lamp 20 and a lighting circuit 30 thereof, and 1 is an outer tube of the lamp 20.
The outer tube 1 is made of a heat-resistant transparent material such as quartz glass or transparent ceramics, and both ends thereof are crushed and sealed. Two metal foil conductors, for example, molybdenum foils 3a and 3 are provided in these sealing portions 2 and 2, respectively.
b and 4a and 4b are sealed, and molybdenum foils 3a, 3b and 4a and 4b are provided with inner lead wires 5a, 5b, 6a and 6b and outer lead wire 7, respectively.
a, 7b, 8a, 8b are connected. The arc tube 10 is attached to the pair of internal lead wires 5a and 5b facing each other.

The arc tube 10 has sealing parts 1 at both ends.
1 and 11 are formed, and the steady discharge electrodes 12 and 12 are sealed in the sealing portions 11 and 11. Electrode 1
The electrodes 2 and 12 are configured by attaching an electrode coil 14 to the tip of the electrode shaft 13. These electrodes 12, 12 are the bulb 1
And are opposed to each other with a predetermined distance between the electrodes.

The base ends of the electrode shafts 13, 13 are welded to metal foil conductors 15, 15 such as molybdenum,
The metal foil conductors 15 and 15 have the above-mentioned internal lead wires 5a,
5b is connected.

Therefore, the internal lead wires 5a and 5b are connected to the electrode 1
2 and 12 are electrically connected to the arc tube 1
It also serves as a support for mechanically holding 0 at the center of the outer tube 1. In such an arc tube 101, a metal halide and a rare gas such as mercury and argon are enclosed.

On the other hand, the other sets of internal lead wires 6a, 6b facing each other are provided with starting discharge electrodes 9, 9 respectively.
Are connected. The starting discharge electrodes 9, 9 are, for example, ring-shaped, and are arranged in the outer tube 1 so as to face each other. The starting discharge electrodes 9, 9 are made of a refractory metal such as tungsten or molybdenum.

The outer tube 1 is filled with a rare gas such as xenon or a mixed gas of xenon and krypton or neon at a predetermined pressure so as to easily generate discharge in the outer tube.

In the metal halide lamp having the double tube structure as described above, for example, in the case of the rating of 35 W, the arc tube 10 has a tube diameter of 5 mm and the electrode distance is 6 mm, and NaI is 8 mg in the arc tube 10. 2 mg of ScI _{3, 3} mg of mercury, and 100 Torr of argon gas were enclosed, and the total luminous flux at the rated lighting was 2800 lumens (lm).

The outer tube 1 is filled with xenon gas at 3 atm. Starting discharge electrodes 9, 9 of this outer tube 1
When 100W is input to, the emission of xenon causes 250
You get 0 lm of light.

The lamp 20 as described above includes a lighting circuit 30.
Is connected to the power source 40 via. The power supply 40 is a commercial power supply and is connected to the external lead wires 7a and 7b via the main switch 31 and the steady lighting ballast 32. Therefore, the arc tube 10 is connected to the power source 40 via the ballast 32 for steady lighting.

The power source 40 includes the main switch 31, the starting lighting ballast 33, and the timer 34.
Is connected to the external lead wires 8a and 8b via. Therefore, the starting discharge electrodes 9, 9 are connected to the power supply 40 via the timer 34 and the starting lighting ballast 33.
The operation of the metal halide lamp 20 and the lighting device 30 having such a configuration will be described. When the main switch 31 is turned on, the voltage of the power supply 40 is simultaneously applied to the arc tube 10 and the starting discharge electrodes 9, 9.

In the arc tube 10, the steady discharge electrodes 12, 1 are provided.
Since the power supply voltage is applied between the two electrodes, the discharge is started between the steady discharge electrodes 12, 12. This discharge is generated in the arc tube 10. Further, since the power supply voltage is applied to the starting discharge electrodes 9, 9 in the outer tube 1, these electrodes 9, 9
The discharge starts in the meantime.

In the arc tube 10, when the lamp is turned off, the metal halide and mercury are aggregated in the coldest portion to form a solid state, which is the steady-state discharge electrodes 12 and 1.
Due to the discharge between the two, it is gradually evaporated by receiving heat from the arc, but it takes several minutes to obtain the total luminous flux in the steady state, and the rise time becomes long. However, at the same time when the arc tube 10 is started, the discharge between the starting discharge electrodes 9, 9 also starts in the outer tube 1, and the discharge in the outer tube ionizes and excites the xenon gas to emit light.

Therefore, when the main switch 31 is turned on, both the arc tube 10 and the outer tube 1 simultaneously emit light,
The shortage of light quantity of the arc tube 10 at the time of starting is compensated by the light emission of the rare gas due to the outer tube discharge. For this reason, a large amount of light emission can be obtained instantly from the time of switching on, and it is not necessary to wait for a rise time of several minutes.

In this way, when the lamp is started and a predetermined time elapses, the arc tube 10 receives heat from the arc due to the discharge inside the outer tube in addition to the internal discharge, so that the temperature of the arc tube rises. It rises sharply, which causes the metal halide and mercury to evaporate in a short time. Therefore, the total luminous flux in the steady state is reached in a short time. That is, the rise time is extremely short.

Then, when such a stable lighting state is reached, the timer 34 operates to stop energizing the starting discharge electrodes 9, 9 in the outer tube 1. Therefore, the discharge in the outer tube is stopped. However, at this time, since the arc tube alone has already reached the steady-state total luminous flux, discharge in the outer tube is not required.
Therefore, the electric power consumption is reduced by stopping the discharge in the outer tube, and the conduction loss is eliminated. FIG. 2 shows the results of experiments conducted on the rated lamps described in the above examples.

As can be understood from this characteristic, a large amount of light can be obtained instantly after the switch is turned on. Then, energization to the starting discharge electrodes 9, 9 is continued for 3 to 5 seconds after the switch is turned on, and the arc tube 10 shifts to stable lighting. Therefore, the discharge in the outer tube may be in a short time, and the starting discharge electrodes 9, 9 is less burdened, and there is no significant increase in power consumption. The present invention is not limited to metal halide lamps, but can be applied to high pressure mercury lamps, high pressure sodium lamps, and the like. Further, the starting discharge electrodes 9, 9 for generating the discharge in the outer tube may be constituted by cold cathodes, filament electrodes, or the like, since their use time is short and the burden is small.

Further, instead of the timer 34, the lamp 2
Even if the control detects the amount of emitted light emitted from 0 with a sensor and detects that the amount of emitted light has reached a predetermined amount of emitted light or more, the discharge in the outer tube is stopped.

[0032]

As described above, according to the high-pressure metal vapor discharge lamp and the high-pressure metal vapor discharge lamp device of the present invention, both are simultaneously discharged by the electrode in the arc tube and the starting discharge electrode in the outer tube when the lamp is started. By this, even if the light emission amount of the arc tube is small, the light amount is supplemented by the discharge in the outer tube, and a predetermined luminous flux can be obtained instantly from the switch-on. Then, while such discharge in the outer tube is continued, the temperature in the arc tube rises rapidly to increase the vapor pressure of the enclosed metal, and the luminous flux of the arc tube reaches the total luminous flux. Time is reduced. Further, when the light quantity of the arc tube reaches the total luminous flux, the discharge in the outer tube is stopped and only the discharge of the arc tube is performed, so that unnecessary power consumption is eliminated and conduction loss is reduced. Furthermore, since no special heater is used, the lamp structure is simplified,
It can be miniaturized.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a metal halide lamp and a lighting circuit.

FIG. 2 is a characteristic diagram showing a relationship between a rising time and a luminous flux.

[Explanation of symbols]

1 ... Outer tube, 9 ... Discharge electrode for starting, 10 ... Arc tube, 12 ...
Steady-state discharge electrode, 20 ... Metal halide lamp, 30 ... Lighting circuit, 31 ... Main switch, 32, 33 ... Ballast,
34 ... Timer, 40 ... Power supply.

Claims (4)

[Claims] 1. A light emitting tube is housed in an outer tube made of a light-transmitting airtight container, a pair of electrodes is sealed in the light emitting tube, and a light emitting metal and a rare gas are sealed in the light emitting tube. Is filled with a rare gas that emits light by electric discharge, and a pair of starting discharge electrodes that are energized at the time of starting to generate an electric discharge in the outer tube by the rare gas are provided in the outer tube. Electric light. 2. The high pressure metal vapor discharge lamp according to claim 1, wherein the rare gas sealed in the outer tube is a rare gas mainly containing xenon. 3. The high-pressure metal according to claim 1, wherein the light-emitting metal enclosed in the arc tube is a metal halide, and thus the high-pressure metal vapor discharge lamp is a metal halide lamp. Steam discharge lamp. 4. A light emitting tube is housed in an outer tube made of a translucent airtight container, a pair of electrodes is sealed in the light emitting tube, and a luminescent metal and a rare gas are sealed in the light emitting tube. Is a high-pressure metal vapor discharge lamp that is filled with a rare gas that emits light by discharge, and that has a pair of starting discharge electrodes that are energized at startup to generate an internal discharge by the rare gas. A voltage is applied to the electrodes in the arc tube and the starting discharge electrode in the outer tube to generate discharges in the arc tube and the outer tube, respectively, and when a predetermined luminous flux is reached, the power supply to the starting discharge electrode in the outer tube is stopped. And a lighting circuit device for controlling so as to maintain only the discharge in the arc tube, and a high pressure metal vapor discharge lamp device.