RU2237315C2 - Metal-halide lamp - Google Patents

Abstract

FIELD: electric engineering.

SUBSTANCE: device has burner manufactured from optically transparent material having sealed electrodes. It is filled with inert gas, mercury, thallium halides, alkaline metal halides, and additives for supplying halides of at least one rare-earth metal to the burner. Some rare-earth metals and mercury halides are useable as the additives for supplying rare-earth metal halides to the burner. Mercury halide quantity is selected to be higher than calculated stoichiometric value with respect to rare-earth metals within limits of 0.02-0.3 mcmole/cm³. Filler ingredients are taken in following quantity in mcmole/cm³: mercury - 2.0-60.0, thallium halides -0.05-1.00, alkaline metal halides - 0.1-5.9, rare-earth metals 0.03-0.9, mercury halides - 0.05-1.20. Inert gas is to be added to reach 1.33-80.0 kPa.

EFFECT: prolonged service life.

4 cl, 1 tbl

Description

The present invention relates to the electrical industry, in particular, improves the design of metal halide lamps for general and special lighting.

Known metal halide lamp containing a burner of an optically transparent material with hermetically sealed electrodes, filled with an inert gas, mercury and thallium halides (1).

In the metal halide lamp described, the thallium halides used in the filling composition determine the green color of the radiation.

The disadvantage of the technical solution for the lamp-analogue is just the presence of green radiation, which distorts the real colors of the lighting objects.

The closest in technical essence is a metal halide lamp containing a burner of an optically transparent material with hermetically sealed electrodes filled with an inert gas, mercury, thallium halides, alkali metal halides and additives to provide the burner with halides of at least one rare-earth metal (2).

As additives for providing the burner with halides of at least one of the rare-earth metals, the dysprosium, holmium and thulium halides are used in the described lamp. These additives provide a white color of radiation with high (over 70 units) color rendering index and light output (up to 100 lm / W).

The disadvantage of the technical solution of the prototype is the low lamp life, which is determined by the use of dysprosium, holmium and thulium halides, which are extremely hygroscopic substances. The latter leads to the fact that water vapor inevitably enters the lamp burner, which dissociates into oxygen and hydrogen in the lamp burner and reduces the lamp burn time.

The technical result of the invention is to increase the lamp life.

The technical result is achieved in that in a metal halide lamp containing a burner of an optically transparent material with hermetically sealed electrodes, filled with an inert gas, mercury, thallium halides, alkali metal halides and additives to provide the burner with halides of at least one of the rare earth metals, as additives rare earth metals and mercury halides were used to provide the burner with rare-earth metal halides, with the amount of mercury halides selected exceeding the calculated stoichiometric with respect to rare-earth metals in the range of 0.02-0.3 μmol / cm ³ and the filling components are taken in the following quantity, μmol / cm ³ :

Mercury 2.0-60.0

Thallium halides 0.05-1.00

Alkali metal halides 0.1-5.0

Rare earth metals 0.03-0.9

Mercury halides 0.05-1.20,

at an inert gas pressure of 1.33-80.0 kPa.

As options in the composition of the lamp filling, dysprosium and holmium can be used as rare-earth metals; cerium; dysprosium, holmium and cerium.

In the metal halide lamp of the present invention, the filling composition is experimentally selected, which allows for a relatively unimpeded introduction into the lamp burner, thereby increasing the lamp life at high light output and color rendering index.

The principle of operation of a metal halide lamp is well described in (3, 4). It is as follows. The lamp in the circuit with ballast and igniter is supplied with a supply voltage. The ignition device, generating a high-voltage electrical pulse, provides ignition of the lamp. An arc discharge arises in an inert gas medium, as it develops, metal halides enter the discharge, including rare-earth ones that generate radiation with high light output and color rendering index.

Pure rare earth metals and mercury halides (iodides and bromides) were used as additives to provide the burner with rare-earth halides. Rare-earth metal halides necessary for the operation of the lamp are formed in the first hours of operation of the lamp as a result of the following reaction:

where Me is a rare earth metal;

X is halogen.

In most cases, argon is used as an inert gas, although in a number of cases, for example, krypton and xenon can be used to ensure faster lamp burning.

The number of filling components introduced into the lamp burner is determined experimentally.

The amount of thallium halides selected in the range of 0.05-1.00 μmol / cm ³ .

When the amount of thallium halides is greater than 1.00 μmol / cm ³ , an excess of them no longer increases the lamp radiation, and the costs of acquiring, storing, and processing thallium halides increase.

When the amount of thallium halides is less than 0.05 μmol / cm ³ , they become insufficient to ensure lamp radiation during the entire service life, since their number decreases in the processes of absorption, adsorption and chemisorption.

The amount of alkali metal halides is selected in the range of 0.1-5.0 μmol / cm ³ .

When the amount of alkali metal halides is less than 0.1 μmol / cm ³ , they are not enough to stabilize the discharge arc, and when the amount is greater than 5.0 μmol / cm ³ , the positive effect of alkali metal halides is exhausted, and the cost of their maintenance is growing .

The amount of rare earth metals is selected in the range of 0.03-0.9 μmol / cm ³ .

When the amount of rare-earth metals is less than 0.03 μmol / cm, they are not enough to ensure the emission of rare-earth metals during the entire service life, and when the amount is greater than 0.9 μmol / cm ³ , the radiation intensity does not increase with increasing costs.

The amount of mercury halides is selected in the range of 0.05-1.20 μmol / cm ³ .

When the amount of mercury halides is less than 0.05 μmol / cm ³ , they are not enough for the formation of reaction (1) of rare-earth metal halides in the required volumes, when the amount of mercury halides is greater than 1.20 μmol / cm, problems arise due to their electronegativity with ignition of lamps and stabilization of the discharge arc during lamp operation.

In addition, the amount of mercury halides selected in excess of the calculated stoichiometric with respect to rare earth metals, in the range of 0.02-0.3 μmol / cm ³

This is done in order to ensure the presence of mercury halides in the composition of the filling components after reaction (1). Excess mercury halides are necessary for the tungsten-halogen cycle in the lamp burner to return the atomized tungsten electrodes from the burner walls to the electrode again (5). The specified process allows to increase the lamp life.

When the amount of mercury halides exceeding the calculated stoichiometric ratio with respect to rare-earth metals is less than 0.02 μmol / cm ³ , the amount of excess halides is not sufficient to provide the described tungsten-halogen cycle, with the amount of mercury halides exceeding the calculated stoichiometric relative to rare earths metals greater than 0.3 μmol / cm ³ , as already indicated, complicates the ignition of lamps and stabilization of the arc of the discharge during lamp operation.

As rare earth metals, dysprosium, holmium, thulium, cerium and other elements are used. Their use is determined by the fact that these rare-earth metals provide a quasi-continuous spectrum of radiation with a high color rendering index and light output.

Examples of specific performance are given in the table.

The application of the invention in the production of metal halide lamps will increase the life of the lamps. So, the increase in the service life of DMG 100 lamps from 200 to 400 hours, achieved as a result of the experiment, at the price of lamps 1800 rubles / pc and annual production of 500 units gives an economic effect of 900 thousand rubles.

Sources of information

1. Kulakov I.A. Metal halide discharge lamps abroad. / Lighting engineering, No. 11, 1982, p.1-4.

2. A.S. USSR No. 694919, BI No. 40, 1979 (prototype).

3. Rokhlin G.N. Discharge light sources. - M .: Energoatomizdat, 1991, p. 522-542.

4. Weymaus D. Gas discharge lamps. / Ed. G.N. Rokhlina and M.I. Fugenfirova. - M .: Energy, 1977, p. 199-226.

5. Minaev I.F. Research, design development and optimization of the manufacturing process of compact metal halide lamps for color cinema. - M., 1987.

Claims (4)

1. Metal halide lamp containing a burner of an optically transparent material with hermetically sealed electrodes, filled with an inert gas, mercury, thallium halides, alkali metal halides and additives to provide the burner with halides of at least one of the rare earth metals, characterized in that as additives to provide the burner with rare earth halides, rare earth metals and mercury halides were used, while the amount of mercury halides was chosen to exceed o-stoichiometric with respect to rare earth metals in the range from 0.02 to 0.3 μmol / cm ³ and the filling components are taken in the following quantity, μmol / cm ³ : Mercury 2.0-60.0 Thallium halides 0.05-1.00 Alkali metal halides 0.1-5.0 Rare earth metals 0.03-0.9 Mercury halides 0.05-1.20 at an inert gas pressure of 1.33-80.0 kPa. 2. Metal halide lamp according to claim 1, characterized in that the composition of dysprosium and holmium is used as a rare-earth metal. 3. Metal halide lamp according to claim 1, characterized in that cerium is used as a rare-earth metal. 4. The metal halide lamp according to claim 1, characterized in that as a rare-earth metal, a composition of dysprosium, holmium and cerium is used.