Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01K—ELECTRIC INCANDESCENT LAMPS
  • H01K3/00—Apparatus or processes adapted to the manufacture, installing, removal, or maintenance of incandescent lamps or parts thereof
  • H01K3/005—Methods for coating the surface of the envelope
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01K—ELECTRIC INCANDESCENT LAMPS
  • H01K1/00—Details
  • H01K1/28—Envelopes; Vessels
  • H01K1/32—Envelopes; Vessels provided with coatings on the walls; Vessels or coatings thereon characterised by the material thereof

Definitions

• the invention relates to an incandescent lamp with a bulb made of soft glass and an inert gas filling with halogen addition, in which provision is made that a reaction of the halogen components of the filling gas with the alkali ions of the bulb glass is not possible.
• the invention also relates to a method for producing such a lamp.
• the hardness of the glass is determined by the linear coefficient of thermal expansion or the so-called transformation temperature. Glasses with an alkali content, for example soda-lime glass, have a greater thermal expansion than glasses without an alkali content and are referred to as "soft glasses". These glasses have the advantage that they can be processed more cheaply than quartz and hard glasses.
• the halogenane part of the filling gas reacts with the alkali, in particular Na ions of the bulb glass to form a thermally stable compound, for example after the reaction Na2Si.03 + 2HBr SiO 2 + H 2 0 + 2 NaBr.
• the reaction products from alkali and halogen lead to undesirable precipitation in the lamp bulb.
• DE-OS 27 01 051 has already proposed to provide the inside surface of the bulb and the surfaces of the internal components with a coating of a constantly impregnating layer , which consists essentially of a metal oxide (A1 2 0 3 ).
• a constantly impregnating layer which consists essentially of a metal oxide (A1 2 0 3 ).
• Such halogen incandescent lamps are not currently manufactured, however, which leads to the assumption that the technology for producing these lamps is not yet mature.
• the difficulty may be that the protective layer is applied so densely that no alkali ions can diffuse through, but on the other hand the optical quality of the glass bulb is not impaired.
• the invention has for its object to provide a halogen lamp with a bulb made of soft glass, in which the above. occurring difficulties can be avoided and which can be technically realized.
• the lamp bulb is depleted of alkali (Na) ions in the region of its inner surface.
• Na alkali
• the resulting vacancies in the glass structure can be filled up by other ions and / or the inner surface of the bulb can be coated with an additional layer of a metal or semimetal oxide.
• the method of manufacture of the halogen incandescent lamp according to the invention corresponds to the method of rinsing and filling the lamp of the method of manufacture of conventional incandescent lamps and therefore does not require any further description.
• the special treatment of the soft glass is carried out by purging the lamp bulb with a treatment gas which is able to remove the alkali ions, in particular Na ions, from the bulb glass.
• a treatment gas should preferably be used which splits off ion types from the series of halogens F, Cl, Br and J which react with the Na ions from the flask glass.
• HCl is suitable as a treatment gas, for example, since hydrochloric acid reacts with Na sodium chloride according to the formula Na 2 Si0 3 + 2HC1 SiO 2. + 2NaCl + H 2 0 forms and this table salt can be easily washed out of the lamp bulb with water.
• the glass material used allows treatment temperatures above 700 C, washing out is not absolutely necessary, since the NaCl produced can sublime and can be flowed or pumped out of the glass bulb with the treatment gas.
• This flushing is intended to anticipate the reaction between the halogen constituents of the filling gas and the Na ions from the bulb glass, which otherwise takes place in the lamp during operation. In order for this reaction to take place in a much shorter period of time, parameters which can be influenced must be varied.
• parameters that can be influenced are only the treatment temperature (T Beh. ) And the treatment duration (t Beh. ).
• T Beh. treatment temperature
• t Beh. treatment duration
• the treatment of the glass surface described can take place in various stages of the manufacture of the bulb or lamp. Treatment during the blowing of the pistons or the drawing of the glass tubes from which the pistons are made has the advantage that the required temperatures are passed through in these process steps, so that no additional heating of the glass is required.
• the finished lamp bulbs it is possible to arrange them in a container through which HCl flows in pure form or with a carrier gas such as N 21 Ar or Kr.
• the container is heated to a temperature so that the temperature of the flask to be treated is more than 500 ° C.
• the gas should act on the inner surface of the lamp bulb at a treatment temperature of, for example, 700 ° C. for at least 3.3 minutes, in order to ensure that no harmful Na concentration is present during the lamp operating time of approximately 200 hours and a lamp operating temperature of approximately 270 ° C. can diffuse the inner surface.
• the lamp bulbs can also be treated in a closed container that contains a sufficient amount of HCl. Because of the changes in the glass surfaces that occur during Na extraction - the creation of stresses, an increase in the softening temperature - it is advantageous to treat only those parts of the bulb that are not in the area of crushing or melting the finished light bulb. For this purpose, the treatment gas can be blown into the flask heated in parallel.
• the treatment can also be carried out on a finished stem lamp, for example integrated into the pumping and rinsing steps which are usually provided in the process sequence before the lamp is filled.
• An alkali depletion at this stage of lamp production also has the advantage that in the subsequent process steps, temperatures no longer occur, which, for example when the lamp bulb is fused to the base, in small areas of the inner surface of the bulb to re-diffuse Na ions from the Glass interior can lead.
• the reaction products are pumped or rinsed out of the stem lamp after the treatment.
• the lamp After the process of alkali depletion in the area of the inner surface of the lamp bulb has been completed, the lamp can be filled with its final filling gas.
• Mg, Ca or Li ions are particularly suitable for filling up these vacancies, since their diameter is approximately the same as that of the Na ions and thus the glass structure is hardly changed by embedding these ions and no stresses occur in the bulb glass .
• Two Na + ions are replaced by one Mg 2+ -, C a 2 + - I o n. Because of the resulting double concatenation in the glass structure, Mg and / or Ca ions are significantly more diffusion and reactive than Na ions and therefore do not form a connection with the halogen components of the filling gas of the lamp.
• lithium when using lithium as a replacement ion, the alkaline earth-like behavior of Li ions is used.
• the replacement ions are introduced into the vacancies by bringing melts or solutions of salts of these ions into contact with the Na-depleted surface.
• the dissociated ions diffuse into the glass surface and saturate the free bonds created by the Na extraction. Even after this process step, it is possible to fill the 4ampe with its final filling gas and to finish it like conventional light bulbs.
• the inner surface of the lamp bulb can be provided with an additional protective layer, which offers an even greater certainty that no Na ions contaminate the filling gas of the halogen incandescent lamp.
• the protective layer is in the form of a metal and / or semimetal Halogen compound, for example TiCl 4 , SiCl 4 , applied to the inner surface of the flask and combines there or on the way there by reaction with water and oxygen to give off the halogen to give a metal or semimetal oxide, for example according to the formula:
• halogen constituents of the metal and / or semimetal halogen compound correspond to those of the filler gas and remain in the lamp as a halogen additive after the reaction has ended. This reaction can also be carried out in the finished lamp.
• Lamp bulbs treated in this way can also be used in all conventional lamps (previously without halogen addition), for which the addition of halogen is now possible if the operating temperature at the bulb is> 200 ° C., so that the tungsten-halogen cycle can take place.
• the halogen prevents premature blackening.
• the lamps according to the invention can be produced more cheaply due to the lower processing temperatures.

Landscapes

• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Glass Compositions (AREA)
• Surface Treatment Of Glass (AREA)
• Vessels And Coating Films For Discharge Lamps (AREA)
• Compositions Of Macromolecular Compounds (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=6143285

Family Applications (1)

Country Status (4)

Families Citing this family (6)

Family Cites Families (5)

• 1981
  • 1981-10-02 DE DE19813139294 patent/DE3139294A1/de not_active Withdrawn
• 1982
  • 1982-09-14 US US06/417,866 patent/US4508991A/en not_active Expired - Fee Related
  • 1982-10-01 DE DE8282109069T patent/DE3278057D1/de not_active Expired
  • 1982-10-01 JP JP57171097A patent/JPS5871556A/ja active Pending
  • 1982-10-01 EP EP82109069A patent/EP0076481B1/fr not_active Expired

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