US3738729A - Production of tungsten halogen lamps - Google Patents
Production of tungsten halogen lamps Download PDFInfo
- Publication number
- US3738729A US3738729A US00170627A US3738729DA US3738729A US 3738729 A US3738729 A US 3738729A US 00170627 A US00170627 A US 00170627A US 3738729D A US3738729D A US 3738729DA US 3738729 A US3738729 A US 3738729A
- Authority
- US
- United States
- Prior art keywords
- iodine
- lamp
- envelope
- tungsten halogen
- iodine compound
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229910052736 halogen Inorganic materials 0.000 title abstract description 7
- 238000004519 manufacturing process Methods 0.000 title abstract description 6
- 229910052721 tungsten Inorganic materials 0.000 title abstract description 6
- 239000010937 tungsten Substances 0.000 title abstract description 6
- -1 tungsten halogen Chemical class 0.000 title abstract description 5
- 239000007787 solid Substances 0.000 claims abstract description 12
- 150000002497 iodine compounds Chemical class 0.000 claims description 16
- OKJPEAGHQZHRQV-UHFFFAOYSA-N iodoform Chemical compound IC(I)I OKJPEAGHQZHRQV-UHFFFAOYSA-N 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 10
- 239000007788 liquid Substances 0.000 claims description 5
- 102100037328 Chitotriosidase-1 Human genes 0.000 claims description 3
- 101000879661 Homo sapiens Chitotriosidase-1 Proteins 0.000 claims description 3
- JOHCVVJGGSABQY-UHFFFAOYSA-N carbon tetraiodide Chemical compound IC(I)(I)I JOHCVVJGGSABQY-UHFFFAOYSA-N 0.000 claims description 3
- CUDGTZJYMWAJFV-UHFFFAOYSA-N tetraiodogermane Chemical compound I[Ge](I)(I)I CUDGTZJYMWAJFV-UHFFFAOYSA-N 0.000 claims description 3
- 229910006149 GeI4 Inorganic materials 0.000 claims 2
- 229910004480 SiI4 Inorganic materials 0.000 claims 2
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 abstract description 14
- 229910052740 iodine Inorganic materials 0.000 abstract description 14
- 239000011630 iodine Substances 0.000 abstract description 14
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical class I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 abstract description 4
- 230000000737 periodic effect Effects 0.000 abstract description 3
- 150000004694 iodide salts Chemical class 0.000 abstract description 2
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- 150000001875 compounds Chemical class 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 239000002904 solvent Substances 0.000 description 5
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 150000002367 halogens Chemical class 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- 101100264195 Caenorhabditis elegans app-1 gene Proteins 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- JHGCXUUFRJCMON-UHFFFAOYSA-J silicon(4+);tetraiodide Chemical compound [Si+4].[I-].[I-].[I-].[I-] JHGCXUUFRJCMON-UHFFFAOYSA-J 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01K—ELECTRIC INCANDESCENT LAMPS
- H01K1/00—Details
- H01K1/50—Selection of substances for gas fillings; Specified pressure thereof
-
- 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
- H01K3/22—Exhausting, degassing, filling, or cleaning vessels
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
Definitions
- Iodine has a vapor pressure which is too high for the lamp to be pumped after introduction of the element, but too low for the iodine to be flushed in at room temperature with the fill gas, such as argon. Cumbersome and expensive techniques are employed to overcome this difficulty, but often involve an undesirable number of manual operations, the risk of introducing harmful impurities or an inability to achieve an accurately controlled dosage of iodine.
- iodine is introducedinto a lamp envelope in the form of an involatile solid iodide or hydroiodide of an element of Group IV (IVB) of the Periodic Table, more especially of carbon, silicon or germanium.
- IVB Group IV
- solid is meant that the compound is a solid at room temperature.
- Preferred examples of such solids are iodoform, carbon tetraiodide, silicon tetraiodide and the germanium tetraiodide.
- the iodine compounds employed in accordance with this invention are soluble in volatile, non-polar, organic liquids, for example petroleum ether, benzene and toluene, and are preferably dispensed into the lamp in solution and the solvent removed to leave the involatile solid compound in the envelope.
- volatile, non-polar, organic liquids for example petroleum ether, benzene and toluene
- the iodine compound in solution can be accurately dispensed into the envelope and the solvent can be removed by evacuation or by flushing with a dry nonreactive gas.
- the lamp can be evacuated on an exhaust system, which can be a rotary machine commonly used in the manufacture of incandescent lamps, and filled with inert gas to the required pressure.
- the iodine compound is only dissociated when the lamp is heated, which is usually achieved by light-ing the filament.
- the preferred procedure is to increase the filament voltage slowly from zero to full voltage over about to 30 seconds to allow the compound to disperse, or to step age" the filament by running at various intermediate voltages, from zero to the rated voltage.
- a controlled and accurately repeatable dose can be dispensed into each lamp.
- the remaining solid is involatile at room temperature and the lamp can be exhausted and gas-filled on a simple vacuum, gasfilling system of the type used for non-halogen lamps, without the need for cold traps or other devices for protecting rotary pumps, valve plates and other components of the system. Because all the iodine remains as an involatile solid during processing, no special maintenance or safety precautions are required on the exhaust and gasfilling system, and the method is very suitable for high speed production techniques.
- the involatile solid compounds defined above have the advantage over gaseous iodine compounds, such as CH I, 011 1 and HI, because the ratio of hydrogen to iodine is lower with CHI and is zero with the compounds used in accordance with the invention. This avoids the difficulty of a reduction in activity of the tungsten transport cycle in the presence of hydrogen (which is useful with bromine or chlorine as halogens, but a disadvantage with iodine).
- Iodoform (CI-Il which has a vapor pressure of only 1.7 X 10 torr 23C, is dissolved in toluene to a concentration of 3 percent weight/volume (i.e. 3g CHI in 100 ml. toluene).
- concentration of 3 percent weight/volume i.e. 3g CHI in 100 ml. toluene.
- 0.025 ml. of this solution is required. It is introduced by in- V serting the needle of a suitably calibrated syringe into the exhaust tube of a lamp envelope, and injecting the required quantity into the lamp envelope. The solvent is then removed by inserting a hollow needle connected to a dry nitrogen supply, and flushing gas into the lamp until the solvent is removed. Raising the bulb wall temperature to approximately C speeds up this operation.
- the lamp is processed as a conventional incandescent lamp on a suitable exhaust/gasfilling system, with the bulb at room temperature. After being filled with gas, the lamp is then lit to dissociate and disperse the iodine compound.
- a tungsten halogen incandescent lamp having an envelope into which iodine is introduced, said envelope being subsequently evacuated and filled with inert gas, the improvement which comprises introducing said iodine into said envelope in the form of an iodine compound selected from the group consisting of iodides and hydroiodides of elements of Group IV of the Periodic Table, said iodine compound being an involatile solid at room temperature.
- a method according to claim 1 which includes the steps of introducing said iodine compound into said envelope in solution in a volatile non-polar organic liquid, and thereafter removing said liquid from said envelope thereby to leave said solid iodine compound in said envelope.
- a method according to claim 1 wherein said iodine compound is selected from the group consisting of CHIg, C14, G614 Ol' 8H4.
- said iodine compound is selected from the group consisting of CHI3, Cl, C614 01' SH- I I l 3
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
Abstract
A method of making a tungsten halogen incandescent lamp in which iodine is introduced into the lamp envelope in the form of an iodide or hydroiodide of an element of Group IV of the Periodic Table which is an involatile solid at room temperature.
Description
United States Patent 9 1 Coxon et al.
PRODUCTION OF TUNGSTEN HALOGEN LAMPS Inventors: George Eric Coxon; John Michael Rees, both of London, England Assignee: Thorn Electrical Industries Limited,
London, England Filed: Aug. 10, 1971 App1. No.: 170,627
Foreign Application Priority Data 11 3,738,729 June 12, 1973 [56] References Cited UNITED STATES PATENTS 3,091,718 5/1963 Shurgan 313/222 FOREIGN PATENTS OR APPLICATIONS 763,062 7/1967 Canada 313/223 900,200 7/1962 Great Britain 313/223 Primary Examiner-Charles W. Lanham Assistant Examiner-J. W. Davie Attorney-Joseph C. Ryan [57] ABSTRACT 4 Claims, No Drawings lamps of short life. For lamps with an intended life of 1,000 hours or above iodine is necessary, or an iodine compound or a mixture with other halogens with iodine predominating.
There are serious difficulties attendant upon the introduction of elementary iodine into the lamp. Iodine has a vapor pressure which is too high for the lamp to be pumped after introduction of the element, but too low for the iodine to be flushed in at room temperature with the fill gas, such as argon. Cumbersome and expensive techniques are employed to overcome this difficulty, but often involve an undesirable number of manual operations, the risk of introducing harmful impurities or an inability to achieve an accurately controlled dosage of iodine. They also tend to be wasteful of iodine In accordance with this invention iodine is introducedinto a lamp envelope in the form of an involatile solid iodide or hydroiodide of an element of Group IV (IVB) of the Periodic Table, more especially of carbon, silicon or germanium. By solid is meant that the compound is a solid at room temperature. Preferred examples of such solids are iodoform, carbon tetraiodide, silicon tetraiodide and the germanium tetraiodide.
The iodine compounds employed in accordance with this invention are soluble in volatile, non-polar, organic liquids, for example petroleum ether, benzene and toluene, and are preferably dispensed into the lamp in solution and the solvent removed to leave the involatile solid compound in the envelope.
The iodine compound in solution can be accurately dispensed into the envelope and the solvent can be removed by evacuation or by flushing with a dry nonreactive gas. After this the lamp can be evacuated on an exhaust system, which can be a rotary machine commonly used in the manufacture of incandescent lamps, and filled with inert gas to the required pressure. The iodine compound is only dissociated when the lamp is heated, which is usually achieved by light-ing the filament. The preferred procedure is to increase the filament voltage slowly from zero to full voltage over about to 30 seconds to allow the compound to disperse, or to step age" the filament by running at various intermediate voltages, from zero to the rated voltage.
By use of the invention a controlled and accurately repeatable dose can be dispensed into each lamp. After the solvent has been removed, the remaining solid is involatile at room temperature and the lamp can be exhausted and gas-filled on a simple vacuum, gasfilling system of the type used for non-halogen lamps, without the need for cold traps or other devices for protecting rotary pumps, valve plates and other components of the system. Because all the iodine remains as an involatile solid during processing, no special maintenance or safety precautions are required on the exhaust and gasfilling system, and the method is very suitable for high speed production techniques.
The involatile solid compounds defined above have the advantage over gaseous iodine compounds, such as CH I, 011 1 and HI, because the ratio of hydrogen to iodine is lower with CHI and is zero with the compounds used in accordance with the invention. This avoids the difficulty of a reduction in activity of the tungsten transport cycle in the presence of hydrogen (which is useful with bromine or chlorine as halogens, but a disadvantage with iodine).
The following is one example of the practice of this invention:
Iodoform (CI-Il which has a vapor pressure of only 1.7 X 10 torr 23C, is dissolved in toluene to a concentration of 3 percent weight/volume (i.e. 3g CHI in 100 ml. toluene). To maintain a satisfactory tungsten transport cycle in a 240V 500W coiled coil linear lamp, having an efficacy of 20 lm/W and 2,000 hr life, 0.025 ml. of this solution is required. It is introduced by in- V serting the needle of a suitably calibrated syringe into the exhaust tube of a lamp envelope, and injecting the required quantity into the lamp envelope. The solvent is then removed by inserting a hollow needle connected to a dry nitrogen supply, and flushing gas into the lamp until the solvent is removed. Raising the bulb wall temperature to approximately C speeds up this operation.
After this the lamp is processed as a conventional incandescent lamp on a suitable exhaust/gasfilling system, with the bulb at room temperature. After being filled with gas, the lamp is then lit to dissociate and disperse the iodine compound.
We claim:
1. In a method of making a tungsten halogen incandescent lamp having an envelope into which iodine is introduced, said envelope being subsequently evacuated and filled with inert gas, the improvement which comprises introducing said iodine into said envelope in the form of an iodine compound selected from the group consisting of iodides and hydroiodides of elements of Group IV of the Periodic Table, said iodine compound being an involatile solid at room temperature.
2. A method according to claim 1 which includes the steps of introducing said iodine compound into said envelope in solution in a volatile non-polar organic liquid, and thereafter removing said liquid from said envelope thereby to leave said solid iodine compound in said envelope.
3. A method according to claim 1 wherein said iodine compound is selected from the group consisting of CHIg, C14, G614 Ol' 8H4.
4. A method according to claim 2 wherein said iodine compound is selected from the group consisting of CHI3, Cl, C614 01' SH- I I l 3
Claims (3)
- 2. A method according to claim 1 which includes the steps of introducing said iodine compound into said envelope in solution in a volatile non-polar organic liquid, and thereafter removing said liquid from said envelope thereby to leave said solid iodine compound in said envelope.
- 3. A method according to claim 1 wherein said iodine compound is selected from the group consisting of CHI3, CI4, GeI4 or SiI4.
- 4. A method according to claim 2 wherein said iodine compound is selected from the group consisting of CHI3, CI4, GeI4 or SiI4.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB3871970 | 1970-08-11 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3738729A true US3738729A (en) | 1973-06-12 |
Family
ID=10405268
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US00170627A Expired - Lifetime US3738729A (en) | 1970-08-11 | 1971-08-10 | Production of tungsten halogen lamps |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US3738729A (en) |
| CA (1) | CA934810A (en) |
| DE (1) | DE2139356C3 (en) |
| GB (1) | GB1318711A (en) |
| NL (1) | NL156539B (en) |
| ZA (1) | ZA715027B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3810685A (en) * | 1970-10-15 | 1974-05-14 | Thorn Electrical Ind Ltd | Manufacture of tungsten halogen lamps |
| US3811063A (en) * | 1972-12-22 | 1974-05-14 | J Rees | Electric incandescent lamps |
| US4065694A (en) * | 1975-02-25 | 1977-12-27 | Westinghouse Electric Corporation | Regenerative-cycle incandescent lamp containing SnI4 additive |
| US4078188A (en) * | 1976-03-30 | 1978-03-07 | Westinghouse Electric Corporation | Regenerative-cycle incandescent lamp containing a dual-additive |
| EP0068655A3 (en) * | 1981-06-23 | 1983-07-27 | Thorn Emi Plc | Tungsten halogen incandescent lamps - mixed halogens |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB900200A (en) * | 1960-03-11 | 1962-07-04 | Union Carbide Corp | Improvements in and relating to electric incandescent lamps |
| US3091718A (en) * | 1960-07-08 | 1963-05-28 | Duro Test Corp | Constant lumen maintenance lamp |
| CA763062A (en) * | 1967-07-11 | Bouwman Lucas | Iodine lamp |
-
1970
- 1970-08-11 GB GB3871970A patent/GB1318711A/en not_active Expired
-
1971
- 1971-07-28 ZA ZA715027A patent/ZA715027B/en unknown
- 1971-08-06 DE DE2139356A patent/DE2139356C3/en not_active Expired
- 1971-08-10 US US00170627A patent/US3738729A/en not_active Expired - Lifetime
- 1971-08-11 NL NL7111083.A patent/NL156539B/en not_active IP Right Cessation
- 1971-08-11 CA CA120275A patent/CA934810A/en not_active Expired
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA763062A (en) * | 1967-07-11 | Bouwman Lucas | Iodine lamp | |
| GB900200A (en) * | 1960-03-11 | 1962-07-04 | Union Carbide Corp | Improvements in and relating to electric incandescent lamps |
| US3091718A (en) * | 1960-07-08 | 1963-05-28 | Duro Test Corp | Constant lumen maintenance lamp |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3810685A (en) * | 1970-10-15 | 1974-05-14 | Thorn Electrical Ind Ltd | Manufacture of tungsten halogen lamps |
| US3811063A (en) * | 1972-12-22 | 1974-05-14 | J Rees | Electric incandescent lamps |
| US4065694A (en) * | 1975-02-25 | 1977-12-27 | Westinghouse Electric Corporation | Regenerative-cycle incandescent lamp containing SnI4 additive |
| US4078188A (en) * | 1976-03-30 | 1978-03-07 | Westinghouse Electric Corporation | Regenerative-cycle incandescent lamp containing a dual-additive |
| EP0068655A3 (en) * | 1981-06-23 | 1983-07-27 | Thorn Emi Plc | Tungsten halogen incandescent lamps - mixed halogens |
| US4532455A (en) * | 1981-06-23 | 1985-07-30 | Thorn Emi Plc | Tungsten halogen incandescent lamps containing mixed halogens |
Also Published As
| Publication number | Publication date |
|---|---|
| ZA715027B (en) | 1972-04-26 |
| CA934810A (en) | 1973-10-02 |
| NL156539B (en) | 1978-04-17 |
| GB1318711A (en) | 1973-05-31 |
| DE2139356A1 (en) | 1972-02-17 |
| NL7111083A (en) | 1972-02-15 |
| AU3216271A (en) | 1973-03-22 |
| DE2139356B2 (en) | 1978-05-11 |
| DE2139356C3 (en) | 1979-01-11 |
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