JPS58155645A - Small metal halide lamp - Google Patents

Abstract

PURPOSE:To obtain a small metal halide lamp with an excellent starting feature, with a long life by preventing premature blackening of a luminous tube due to spattering and with a satisfactory light flux of 50 watts or less by specifying the type and sealing pressure of the starting rare gas, the distance between electrodes and the lamp power. CONSTITUTION:Mixed gas of neon of 10-50% and argon is used as the starting rare gas sealed in a luminous tube 1, and if the relationship between the sealing pressure p(mm.Hg) of the rare gas and the distance l(cm) between main electrodes is kept at 25<=pXl<=85, an effective starting feature and lumen maintenance factor are improved. And if an equation 5X10<-3>XW+5X10<-2=l<=1.9X10<-4>X W<2>+3.2X10<-1> is satisfied, where W(wat) is the lamp power, a small metal halide lamp of 50 watts or less with excellent efficiency can be available.

Description

[Detailed description of the invention] [Technical field of the invention] This invention - A small metal halide drain f of less than 50W and T
K44), 41 regarding the modification of its starting characteristics and efficiency.

[Background of the IIO technical debate and its problems]

Most of the conventional examples of intralayer jI1 are incandescent light bulbs and fluorescent lamps. However, in recent years, from the standpoint of zero energy conservation,
Efforts are being made to develop small metal halide lamps with high efficiency and excellent color rendering, especially 50W lamps and undersized lamps.

Conventional metal halide lamps are limited to medium and high wattage types of 250 watts, 2 kilowatts of torque, and 20 to 40 mHg of argon gas as a starting gas sealed in the arc tube. 0.0 if the run fO is sealed or can be started with a mercury lamp ballast.
Neon gas (Penning gas) made by mixing 1 to 10.0 inches of argon, krypton, or xenon
Approximately 0■Hi was enclosed. However, the distance between the electrodes of small metal halide lungs of 50 W or less is 1.0.
am or less, and the lamp current is also small, so it is difficult to start the lamp with the gas pressure filled in the conventional medium/high power or T-shaped rung.

Also, a small metal halide drain of less than 50 watts! In this case, the internal volume of the arc tube is regulated to be less than 〇.In other words, in an I-type metal halide lamp of 50 watts or less, if the internal volume of the arc tube is made larger than the IOC, there will be less evaporation of the luminescent metal enclosed, and the amount of light emitted will be insufficient. It is. Therefore, the internal volume of the arc tube for metal halide lamps of 50 watts or less is regulated to be less than Ice, and this book is very small.
Therefore, since neon gas is the main component (with Ender gas, the molecular weight of neon is small, the electrode material tends to sputter when starting the lamp, and the electrode material tends to adhere to the wall of the arc tube, leading to early deterioration and a decrease in luminous flux. There are some discrepancies that make it difficult to wear.

[Departure-O purpose]

The present invention was made based on these circumstances, and its purpose is to start! Excellent IK and armpit,
4. It is an object of the present invention to provide a small metal halide lamp of less than 50 watts, which has a long life by preventing early blackening of the arc tube due to the ring, and has a satisfactory total luminous flux.

[Summary of the invention]

Select the type of rare gas for starting the original Wi4Fi, and control the relationship between the pressure of the starting rare gas and the distance between the electrodes.
Furthermore, the above object is achieved by regulating the relationship between the distance between the electrodes and the lamp power.

[Embodiments of the invention]

An embodiment of the present invention will be described below based on the drawings.

In the figure, 1 is an arc tube made of quartz glass, etc., and the discharge space is formed in a spherical or elliptical shape. This is to promote the convection of the vapor of the metal halide sealed in the discharge space to increase the amount of evaporation, and the internal volume of this discharge space is defined as Ice in order to promote the evaporation of the metal halide. is regulated. The arc tube 1 is normally housed in an outer tube (not shown) and has a double tube structure, as is the case with conventional large metal halide lamps. Inside the arc tube 1 are main electrodes 2 facing each other.
a * j b are provided, and these main electrodes are 1 m long.
, 2b are connected to metal foils 4, 4 made of molybdenum or the like sealed in sealing parts 3, 3 formed at both ends of the arc tube 10. Note that the metal foil 4°4 is connected to external lead wires 5,5.

The arc tube 1 is filled with a predetermined amount of mercury, a metal halide, and a starting rare gas. A mixture of neon and argon is used as the starting rare gas. In this case, the mixing ratio of neon is controlled within the range of 10 to 5 degrees, that is, the amount of neon with a warm molecular weight is kept small.

The present inventors have established the present invention based on various experiments and researches, and the present invention will be explained below with reference to each experiment.

First, the inventors of the present invention changed the starting rare gas 0 filling gas pressure to the #l[F')? I checked it out.

[Experiment 1, 50 watts] Main electrodes were placed opposite each other with a distance between the electrodes of 1=0.5 an in a spherical arc tube made of quartz glass with an inner diameter of 10.0 mm and a wall thickness of 1.0 mm. The main electrode is a tungsten electrode shaft with a wire diameter of 0.3 mm and a tungsten coil wound in two layers. Inside the arc tube, 8IIIF of mercury, scandium iodide (S e I s ), and sodium iodide (NaI) were placed at 8 e I s : Na I =1.
: 5 (weight S) and a total amount of 3 ■ was sealed. Neon-argon (No.: Ar ~ 40:
The rung starting voltage was measured using a mixed gas of 60) and varying the pressure of the sealed gas. As the ballast, a choke-type ballast for mercury lamps was used.

This result is shown as characteristic A in FIGS. 2 and 3, respectively. In characteristic A of FIG. 2, the broken line indicates the glow starting voltage, and the solid line indicates the arc starting voltage. Second
As is clear from the figure, the lower the filled gas pressure is, the easier it is for glow discharge to occur, but the more difficult it is for arc discharge to occur, and the higher the filled gas pressure is, the more likely glow discharge and arc discharge are to occur separately and at the same time. Become so. It can also be seen that there is a peak value where the sealed gas pressure is the minimum value. - The discharge starting voltage must be normally regulated to 180V or less in anticipation of the voltage drop in the power supply voltage, so it is 50W from Figures 2 and 3.

In the case of T-type metal halide Ranzo, the distance between the electrodes is 1 =
When the enclosed Qx pressure P at 0.5 m is 50 to 190, it is 25:ihP X j ≦9! S・-・
River... - It can be seen that it is within the range of (1).

[Experiment 2 = 40 watts] The main electrodes were placed to face each other in a spherical arc tube made of quartz glass with a wall thickness of 1.0 mm and an inner diameter of 7.0 mm, with a distance between the electrodes of 1 = 0.4 tvn. The electrode axis diameter of the main electrode is 0.2 m, and 6 Iv of mercury and 8 a.
I3: Na1-1: 5 (weight*) with a total amount of 2 Da, and as a rare tr.
Penning gas was used.

The characteristics of a typical lamp are indicated by B in FIG.

It is clear from this that the sealed gas pressure of the ζ2 40 watt metal halide lamp is s O ~ 220 (mHg).
24 ≦P X l ≦88 −・−・−(2
) is required.

[Experiment 3: 20 watts] Main electrodes were placed facing each other in a spherical arc tube made by Sekiho, with an inner diameter of 6.0 mm and a wall thickness of 1.0 ■δ, with a distance between the electrodes of 1 = 0.3 m. The electrode axis diameter of the main electrode is 0.15 square meters, and the coil is wound in two layers. Inside the arc tube, there is 41v of mercury and 8alx:Na.
I~1:5 (weight*) and a total amount of 1M9 is sealed, and Jung gas (Ne:Ar=40:60) is used as a rare gas.

This rung has the characteristic indicated by C in FIG. As you can see from this, the 120 watt metal halide lamp has a sealed gas pressure of 70 to 285 (mug).
When converted to PX71, 21≦PX/≦85 ・・・−・−・(3)
becomes.

As you can see from equations (1) or 3) above, metal halide lanterns with a power of less than 50 watts! In, 25≦PX7
≦85 If the range (4) is satisfied, the engine can be started reliably.

The above results show that neon is 40% and argon is 60%.
Next, we examined the mixing ratio of neon gas. If the internal volume of the arc tube is 1 (for small metal halide drains of C or less, the electrode material will adhere to the edges and center of the arc tube at the time of startup), causing early blackout. cause

This is due to the fact that the distance J between the line electrodes is very small, 5- or less. In order to suppress this blackening and improve the luminous flux maintenance factor, it is not possible to use a large amount of neon gas. That is, because neon gas has a small molecular weight, it has a small effect of suppressing sludge and talinda of the electrode material. Also, using krypton or xenon gas helps prevent blackening, but this increases the rung starting voltage,
This metal halide run below 1150 watts! 18
It becomes difficult to start at a voltage below 0V. Therefore, it is necessary to use a gas that is mainly composed of argon and mixed with Al-fyK neon at a relatively small mixing ratio.

The run using a mixture of 4091 neon gas and 9 argon gas is the same as the above [Experiments 1 to 330 times].

Therefore, the present inventors varied the mixing ratio of neon gas to argon gas and investigated the luminous flux maintenance rate and degree of blackening. The results are shown in [Table 1], and the evaluation after flashing 7500 times for each run is shown.
If it exceeds Sc, blackening due to sputtering will increase and the luminous flux maintenance rate will decrease. Therefore, the mixing ratio of neon to argon must be regulated to below Sc. If the ratio is less than 10-, -
Run for 20 COtkm! Starting voltage is 4210 ~ zsov and tb in Watt O Lang,
The power supply voltage of 200 V-t for 200 V-t" cannot be used because it is impossible to start, and it cannot be used at the power supply voltage of taov, which takes into account the variation of the intermediate power supply voltage of ±10 V. - This is because the temperature is low, The inning effect of nt occurs as CK This is thought to be due to the fact that a metastable state is difficult to form], and the effect of argon and neon is completely eliminated.

Therefore, the mixing ratio of neon to argon is 10 to 5.
It is regulated to a range of 0.

In addition, each watt run has a neon gas mixture ratio of 10 to 50%! Then, the starting voltage is determined by the characteristics A, B, and
It has been confirmed that the variation remains within the measurement error of C, and there are no problems with startability.

By the way, in general, metal halide lamps have conventionally been filled with 3N metal halides such as sodium (Na), thallium (Tj), and indium (Iho). As shown in [Experiments 1 to 3], rare earth metals containing sodium, scandium (Sc), and yttrium (Y), especially halides of scandium and sodium, are being adopted. Lamps using scandium and sodium halides have particularly excellent lamp efficiency and light color, but because scandium has strong hygroscopic properties, they easily carry H, O, etc. into the arc tube, and this type of small metal halide lamp Even a small amount of H2O tends to increase the starting voltage. In order to prevent this, the present inventors sealed scandium in the arc tube separately from the scandium halide, so that the amount of scandium in the arc tube would be excessive, but this excess range would be less than 1 da per 1 cc. This result is shown in the characteristics of a 50W, T-shaped metal halide lung in Figure 2.

In other words, when we consider the reason why rung D, in which scandium is filled excessively, has a lower starting voltage, as can be seen by comparing Figure 2 A and D, we first find that As a result of an analysis of the distance between the lamp of M and the rung of D in the figure, it was revealed that the impurity gas in the arc tube of lamp D was extremely small. Despite the small internal volume of the arc tube for small rungs of 50 watts or less, the amount of impurities contained in the arc tube wall and filler, as well as impurities mixed in during the sealing process, is relatively small. Moisture and hydrogen are present in the arc tube.However, as shown in the table, in lamp D, which is filled with an excessive amount of scandium, the above-mentioned non-IR gas is extremely small, and scandium is
It is thought that it acts as a detergent and adsorbs impurities. Scandium also has other effects in addition to the ivy effect described above. In other words, in this type of rung, sodium is lost during its lifespan and an excess of free iodine is generated, and this free iodine reacts with mercury to form mercury iodide. (HgI) is formed, which causes an increase in lamp voltage. However, if scandium is filled in excessively, this scandium reacts with free iodine to form 5eIi, which causes the generation of IgI. This prevents the rung voltage from rising during its life, and even from turning off.

Enclosing scandium in excess in the arc tube in this way is effective in lowering the starting voltage of the lamp and also prevents the lamp voltage from increasing; however, if scandium is in excess of more than 1 cc per 1 cc of the internal volume of the arc tube, Excessive scandium adheres to the wall of the arc tube during lamp operation, giving it a brownish color and causing a decrease in luminous flux, so it is necessary to keep it within a range of 1 cm per 1 cc.

On the other hand, the above explanation is similar to Run! We have focused only on the starting voltage, but Run! Regarding starting characteristics, the time required for starting cannot be ignored. Therefore, the present inventors measured the start-up time of the 0-W, G-carved metal halide lung (used in [Experiment 1]).

The results are shown in FIG. In other words, the starting time increases as the new gas pressure increases. 50
In the case of Watt-type lamps, the filled gas pressure is regulated to a range of 50 to 190 mg (as can be seen from Figure 2), but in the gas pressure range 8 of 50 to 190 μHg, the time required for starting is It is clear that the duration ranges from 1 to about 9 minutes. If the starting time is long like this, it will take a long time for the transition from glow discharge to arc discharge, and during this time the tungsten in the electrode will scatter, causing blackening of the arc tube and reducing the luminous flux. It has a short lifespan. Moreover, the long time it takes to start up increases the waiting time, making it impractical as an indoor light source.

Therefore, the present inventors added promethium (Pm) inside the arc tube.
As shown in Figure 4, the starting time becomes longer as the voltage increases because the initial amount of electrons is insufficient. Initial electrons are supplemented by adding a substance.

In the 50W, T-shaped metal halide lung related to [Experiment 1], the pressure of the filled gas of 40% neon and 60% argon was 120 μHg, and scandium was added at 0.2y/cc in anticipation of the aforementioned gluing effect. Enclose and further 0.001
We measured the starting times for Microchip and Lee 10C lamps containing promethium and lamps without promethium, and the results were as shown in the table below.

As can be seen from the above results, it can be seen that the Nine Rungs with promethium included greatly shorten the starting time and start almost instantly.

It can also be confirmed that by sealing in promethium, there is no disturbance in the starting voltage.
Equivalent effects are observed. However, it is necessary that the amount of radioactive substance sealed is at least 0.0001 microki, ri per arc tube inner volume ICC, and less than 1, off ki, ri. o, oooi microki,
If it is less than 0/CC, it will not be effective in shortening the startup time, and if it exceeds 1.0 microki, lJ/cf, the handling will be subject to legal regulations, so in experiments with 0 or more, which is undesirable, Although we have shown examples focusing on improving the starting characteristics and luminous flux maintenance rate (blackening), one of the characteristics of this type of small metal halide rande is that it is excellent in efficiency, so we investigated the total luminous flux.

A factor that influences the total luminous flux is the relationship between the distance l between the electrodes and the lamp power (W).

Therefore, the present inventors investigated the rate of change in the total luminous flux when changing the inter-electrode distance 1 for a 40 watt metal halide rande in which a mixed gas of 40 cm of N and 601 g of Ar was sealed with 140 Hg.

The results are shown in FIG. Distance between electrodes! (- is 0, 6
If it exceeds am, the tube wall load becomes too small and the temperature of the lowest cooling cannot rise sufficiently, so the evaporation of the metal halide decreases and the light emission is mainly due to mercury, so the total luminous flux becomes 2750 Iwn or less. Also the distance between the electrodes! When the distance is less than 0.25 m, the total luminous flux decreases to 27,501 m or less due to the shortening of the emitting arc length. Therefore, the metal halide lan fFC of 40 watts and
The distance between the electrodes! It is necessary to regulate it within the range of 0.25 to 0.61.

Such experiments were carried out at 20 W, T and 50 W.

When the test was carried out for each of the two rungs, and the compatible range of the total luminous flux was graphed based on the relationship between the distance between each electrode and the rung power, the characteristics shown in FIG. 6 were obtained. In Figure 6, l=1.9X10 XW+&z+x1'o'vPuj
The area surrounded by -5X10-3XW+5X1 o-2o range m is the range that passes the total luminous flux.

Hence the distance between the electrodes! is 5X10-sXW+5X10-ffi≦)≦1.9
10-'XW2+3.2X10-'・・・・・・・・・
...It can be seen that it is sufficient to satisfy (5) O. If we summarize the various experiments described above, we can use aluminum gas with a mixture ratio of 10 to 50% neon as the starting rare gas, and use this Enclosed pressure of rare gas P (wgHg) and distance between main electrodes・! If the relationship with (country) is set to 25≦Pxl≦85, it will have an effect on starting characteristics and luminous flux maintenance rate. When power is W (watt), 5 moi 0-&xW+5X10-"<7≦1.9X10-'
If xW2+3.2xlO-' is satisfied, a small metal halide lamp of 50 watts or less with excellent efficiency can be obtained.

In addition, for more practical starting characteristics, rare earth metals are encapsulated in excess in a range of 1 w/ac or less, and radioactive substances are further added to 1 to 1 × 10 microCuI)-/Cr,
If it is enclosed within the range of , even better runde can be achieved.

〔Effect of the invention〕

As detailed above, the present invention uses an arunone gas mixed with 10 to 5091 neon as the starting rare gas in a small metal halide lung of 50 watts or less, and the pressure of the charged rare gas is P smog and the distance between the main electrodes is jl.
When 25≦PX7≦85 and the rung power is W watts, 5X10-
'XW+5X10-'≦1≦1.9X10-'X W2
+3.2-110-'.

Therefore, according to this document, in a metal halide lamp of 50 watts or less, the starting voltage is lowered to make starting easier, and the smearing of one electrode is suppressed to prevent early blackening, and the luminous flux maintenance rate is reduced. . Furthermore, it becomes possible to improve the lamp efficiency due to the total luminous flux, and the practical use of small metal halide lungs becomes possible.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a configuration diagram of an arc tube O, FIG. 2 is a starting voltage characteristic diagram of a 50W, TOMETAL NO 1 Ride lamp, and FIG. g and 2
Figure 4 shows the starting voltage characteristics of a 5°W metal halide lamp, and Figure 5 shows the starting time characteristics of a 5°W metal halide lamp. FIG. 6 is a total luminous flux characteristic diagram according to the inter-electrode distance and rung power. 1... Arc tube, j a + j b... Main electrode,!
... Distance between electrodes. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 Driving bus/lf (mmHg)

Claims (1)

[Scope of Claims] (1) In a small metal halide lung of 50 watts or less, which has an arc tube having opposing main electrodes and enclosing mercury, a metal halide, and a starting rare gas in an outer bulb, As the rare gas, alponic gas mixed with 10 to 50% neon is used, and the sealing pressure of this rare gas is set to P (■
Hg), when the distance between the main electrodes is / (cIn), and when the lamp power is W (watts), 25≦PX
When j≦85, 5X10-3XW+-5X10-2≦j≦1.9X10
A small metal halide lung characterized by satisfying the relationship: ""XW2+3.2110-'. Claim No. (1) 19, characterized in that a small metal halide lung 0 (3) of the arc tube is filled with a rare earth metal in an excess amount in the arc tube with an internal volume I CCMJ 1w or less O range. is the small metal halide dolan in item (2)! . (4) Kf in the arc tube vs. radioactive substances such as metium,
A small metal halide lamp according to the patent specification (1) or (2), which is characterized in that the lamp is filled with at least 100 yen.