US3662203A - High pressure saturated metal vapor, preferably sodium or metal halide vapor discharge lamp - Google Patents

High pressure saturated metal vapor, preferably sodium or metal halide vapor discharge lamp Download PDF

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US3662203A
US3662203A US36318A US3662203DA US3662203A US 3662203 A US3662203 A US 3662203A US 36318 A US36318 A US 36318A US 3662203D A US3662203D A US 3662203DA US 3662203 A US3662203 A US 3662203A
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lamp
outer envelope
discharge vessel
diameter
vapor
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US36318A
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Bernhard Kuhl
Alexander Dobrusskin
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Osram GmbH
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Patent Treuhand Gesellschaft fuer Elektrische Gluehlampen mbH
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Priority claimed from DE19696920340 external-priority patent/DE6920340U/en
Priority claimed from DE19691957978 external-priority patent/DE1957978C3/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01K—ELECTRIC INCANDESCENT LAMPS
    • H01K1/00—Details
    • H01K1/42—Means forming part of the lamp for the purpose of providing electrical connection, or support for, the lamp
    • H01K1/46—Means forming part of the lamp for the purpose of providing electrical connection, or support for, the lamp supported by a separate part, e.g. base, cap
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J5/00—Details relating to vessels or to leading-in conductors common to two or more basic types of discharge tubes or lamps
    • H01J5/48—Means forming part of the tube or lamp for the purpose of supporting it
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J5/00—Details relating to vessels or to leading-in conductors common to two or more basic types of discharge tubes or lamps
    • H01J5/50—Means forming part of the tube or lamps for the purpose of providing electrical connection to it
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00—Gas-discharge or vapour-discharge lamps
    • H01J61/02—Details
    • H01J61/30—Vessels; Containers
    • H01J61/34—Double-wall vessels or containers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01K—ELECTRIC INCANDESCENT LAMPS
    • H01K1/00—Details
    • H01K1/28—Envelopes; Vessels
    • H01K1/34—Double wall 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

  • FIGA A first figure.
  • the invention relates to a high pressure discharge lamp using an essentially saturated metal, or metal halide vapor, preferably a sodium vapor or a metal halide vapor discharge lamp with its discharge vessel, the so-called arc tube, hermetically sealed in an outer envelope.
  • the arc tube is enclosed in a single-ended ellipsoidal (see German Pat. No.
  • the volume of the outer envelope is a multiple of the volume of the discharge vessel, and the ratio of diameter of outer envelope to diameter of arc tube is relatively large, for instance, in a metal halide vapor discharge lamp with a wattage input of 400 W, larger than six.
  • the relative sizes of the envelope and are tube are changed so that the ratio of inner diameter of the outer envelope to outer diameter of the arc tube is substantially less, that is from 3:1 to I .05zl.
  • the outer envelope is of thermally highly loadable material capable of withstanding a temperature exceeding 500 C, such as quartz glass. It encloses the discharge vessel comparatively closely without however coming in contact with the latter.
  • the discharge vessel likewise, is of thermally highly loadable material.
  • the temperature of the outer envelope is increased in operation; in consequence of heat radiation from the outer envelope, additional heating of the arc tube is effected and thus the vapor pressure increase in the discharge.
  • the outer envelope has to be made from a material which can be highly stressed thermally.
  • a cylindrical tube of quartz glass is suitable. Photometrically, an envelope of sapphire would be even better. Costs make such material uneconomical; increasing the temperature of the arc tube beyond certain ranges does not proportionately increase light output.
  • the outer envelope is preferably made in double-ended form.
  • the outer envelope is closed at each end by a pinch seal preferably of l-type cross-section, enveloping the lead-in wires.
  • the bases of insulating material for example, of a ceramic material, are so shaped that one of its ends is provided with a slotted cylindrical portion.
  • the legs of the base resulting therefrom are closely embracing the flat midsection of the pinch-seal.
  • the lead-in wire is guided to the exterior by way of a contact pin passed through the base.
  • Both bases of the outer envelope may be located in the direction of the lamp axis; or in order to obtain a reduction in lamp length, at least one of the bases of the outer envelope can be mounted at right angle to the lamp axis, an arrangement which is advantageous primarily in lamps of high wattage input, for example, 5 kW.
  • the inner wall surface of the outer envelope may be provided with an infrared (IR) radiation reflective coating of, for example, tin oxide; IR-radiation absorbing additives in the material of the outer envelope proved likewise suitable. Similar measures are also applicable for absorption of shortwave UV radiation and thus for suppression of objectionable formation of ozone, for example, coating with, or addition of TiO,.
  • IR radiation reflective coating of, for example, tin oxide
  • Similar measures are also applicable for absorption of shortwave UV radiation and thus for suppression of objectionable formation of ozone, for example, coating with, or addition of TiO,.
  • FIG. 1 is a schematic cross-sectional view of the structure of a 400 W metal halide vapor discharge lamp
  • FIG. 2a is a graph showing the luminous efficiency (ordinate) of a 400 W discharge lamp containing dysprosium iodide plotted against temperature (C) and vapor pressure
  • FIG. 2b shows a section of the color triangle wherein the chromaticity coordinates of the light are shown for a lamp either with quartz or glass envelope;
  • H6. 3 is a schematic elevation of the structure of a 400 W high pressure sodium vapor discharge lamp
  • FIG. 4 is a schematic view of a lamp having one base extending at right angle
  • FIG. 5 is a fragmentary cross-sectional view of a lamp base.
  • the discharge vessel 1 of quartz glass is sealed at its opposite ends by a pinch seal 2, 3 each, through which the lead-in wires 4, 5 are passed in vacuum-tight manner.
  • the filling of the lamp comprises, for example, 20 mg of Hg, 2.5 mg of Dy, 10 mg of Hgh, 5.5 mg of TH and Ar at 30 torr in a volume of 16 cc.
  • the end portions of the discharge vessel 1 are provided with a radiant-heat reflecting coating 6 of 21 02.
  • the ends of the lead-in wires 4, 5 extending outside the discharge vessel 1 are electrically connected with a disk 7 of metal, for example, of nickel or molybdenum.
  • the disk 7 has at its periphery a plurality of supports 8 which are used as resilient mounting support of the discharge vessel 1 in the enclosing outer envelope 9 of quartz glass.
  • the inner surface may be coated as schematically shown at 9', with an IR, or UV (or both) reflective coating.
  • One conductor 10 or ll, respectively, is connected to the lead-in wires 4, 5 via disk 7, said conductors extending hermetically sealed, through the ends of the outer envelope by means of flat pinch seals 12 or 13.
  • the ceramic bases l4, 15 are affixed to the pinch seals l2, l3.
  • l6 denotes the getter material provided within the outer envelope.
  • the outer envelope 9 may either be exhausted or filled with nitrogen or argon of about 700 torr cold pressure. Suitable dimensions for a 400 W lamp:
  • the inner diameter of outer envelope 9 is 27 mm;
  • the outer diameter of discharge vessel 1 is 22.5 mm
  • the lamp If the lamp is operated in horizontal position with a wattage input of 400 W and an operating voltage of about l05 V, it has a luminous efficiency of about 70 lm/W. If operated in vertical position, the luminous efficiency is approx. lm/W.
  • outer envelope 9 has an inner diameter of 50 mm
  • the luminous efficiency of such a lamp is lm/W in horizontal operating position.
  • the curve shown in FIG. 20 applies to 400 W lamps with a constant arc tube wall load of 10 W/cm.
  • Point A indicates the luminous efl'lciency 1 for a lamp with an ellipsoidal outer envelope of glass
  • point B for a lamp with an outer envelope of quartz according to the invention.
  • Glass may still be used (for thermal reasons) as the material for the outer envelope
  • quartz should be used.
  • limit line Q higher thermally loadable materials should be used which may, however, due to their cost, be uneconomical commercially. in the section of the color triangle shown in FIG.
  • FIG. 3 the discharge vessel 17 of the high pressure sodium vapor discharge lamp is of light-transmissive alumina ceramic; its ends 18 and 19 are hermetically sealed in known manner.
  • the filling comprises sodium, mercury and a basic gas, for example, xenon or argon.
  • the mounting support of the discharge vessel and the feed through of the lead-in wires are similar to the embodiment of FIG. 1 and have been given the same reference numbers.
  • the inner diameter of the outer envelope 9 is 20 mm
  • the outer diameter of the discharge vessel 17 is 9 mm, so that the two vessels are spaced a distance of 5.5 mm.
  • the complete lamp has an overall length of about 20 cm.
  • the wattage input of the lamp is 400 W, the luminous efficiency about 100 lm/W.
  • the double-ended structure permits ignition of the lamp even under hot operating conditions by means of ignition devices with high starting pulses (30 kV) which is impossible in case of single-ended lamps due to the possibility of spurious arc-over caused by the small spacings at the base, lamp socket and fixture.
  • FIG. 4 shows a kW lamp with conventional cylindrical seals having an outer envelope 9, and in-line base 20 and a base 2l at the other end of the lamp extending at right angle with respect to the center line or axis C of the lamp.
  • both bases 20, 21 can be of the angle type.
  • H6. 5 is a cross-sectional view taken along lines VV of FIG. 3 of a base and the lamp foot.
  • the press 12 of the lamp is an I cross-section, with a foil type electrode lead embedded and sealed therein.
  • Two legs 22, 23 of a slotted base portion 14 embrace the l-shaped press.
  • High pressure metal vapor discharge lamp with saturated vapor in operating condition of the lamp comprising:
  • a discharge vessel (1) of thermally highly loadable material permitting an operating temperature exceeding 500 C confining an arc-type discharge and forming an arc enclosing tube, and having a wall load exceeding 10 W/cm;
  • the spacing between the inner diameter of the outer envelope (9) and the outer diameter of the discharge vessel 1) being defined by a ratio of from 3:1 to 1.05:] to provide radiation of heat from the discharge within the discharge vessel (1) to the outer envelope (9) and radiation back of such heat towards the discharge vessel (1) to additionally heat said vessel to the extent that vapor density is additionally increased apart from the increase in vapor pressure.
  • pinch seal is provided at each end of the outer envelope, said pinch seal being of l-shape in cross-section.
  • Lamp as claimed in claim 3 including a substantially cylindrical base of insulating material with slotted end portion constituting two opposed legs (22, 23) which closely embrace the flat mid-section of the pinch seal.
  • Lamp as claimed in claim 1 wherein the two bases of the outer envelope are extending in the direction of the lamp axis.
  • Lamp as claimed in claim I wherein at least one of the bases of the outer envelope is mounted at right angle to the lamp axis.
  • Lamp as claimed in claim 1 wherein the material of the outer envelope comprises [R-absorbing additives.
  • Lamp as claimed in claim I for 5 kW input wherein the discharge vessel has an outer diameter of about 3% cm and the outer envelope has an inner diameter of about 5 cm.
  • Lamp as claimed in claim 1 wherein the discharge vessel contains halides of metal.
  • Lamp as claimed in claim 14 for 400 W input wherein the discharge vessel has an outer diameter of up to about I cm and the outer envelope an inner diameter of about 2 cm.
  • Lamp as claimed in claim 1 wherein the material of the discharge vessel (1) is quartz glass.
  • Lamp as claimed in claim 1 wherein the material of the discharge vessel is lighttransmissive alumina ceramic.

Abstract

The outer envelope is of thermally highly loadable material capable of withstanding operating temperatures exceeding 500* C, such as quartz glass. It surrounds the actual arc enclosing vessel, which is likewise of thermally highly loadable material, such as quartz glass. The spacing is so close that additional heating, by thermal radiation from the outer envelope results in increased vapor density in the arc since the metal vapors in metal halide vapor discharge lamps are essentially saturated during lamp operation. A suitable ratio of the inner diameter of the outer envelope to the outer diameter of the discharge vessel is 3:1 to 1.05:1; the diameter difference being smaller than 2 cm.

Description

C United States Patent 1151 3,662,203
Kuhl et al. 1 51 May 9, 1972 HIGH PRESSURE SATURATED METAL rences Ci VAPOR, PREFERABLY SODIUM OR UNITED STATES PATENTS METAL HALIDE VAPOR DISCHARGE 3,400.288 9/1968 Grothm 1 3/1 12 x LAMP R2l,823 6/194] Burns ....313/112 x 1 [72] Inventors: Bernhard Kuhl, Grunwald-Geiselgasteig; 3212:; P mmsskin Tauflmhen' bmh 2.001.528 5/1935 Grootet al "313 25 "many 3,259,777 7/1966 Fridrich ....3l3/l84 [73] Assignee: Patent-Trguhand-Geggllgchafl fur glgk. L961] l9 6/1934 Uyterhoeven .3 1 3/25 trische Gluhlampen mbl'l, Munich. Germany Primary Examiner-Roy Lake Assistant Examiner-Palmer C. Demeo [22] Fled: May 1970 AttorneyFlynn & Frishauf 21 A l.N 36 l8 1 PP 0 57 ABSTRACT [30] Foreign Appnca'hn Priority DE" The outer envelope is of thermally highly loadable material capable of withstanding operating temperatures exceeding Nov. l8 1969 Germany ..P 19 57 978.3 500 C, such as quartz glass. lt surrounds the actual arc enclos- May 20, 19159 German G 69 20 340.3 ing vessel, which is likewise of thermally highly loadable material. such as quartz glass. The spacing is so close that ad- 2] U Cl --3l3/25, 313/1 12, 313/184, ditional heating, by thermal radiation from the outer envelope 3l3/220, 3l3/22l, 313/227 results in increased vapor density in the are since the metal [5 H [nL CL "011 61/34, H0 61/35 vapors in metal halide vapor discharge lamps are essentially [58} Fwd of Search "313/25 84 22] 227 1 l2 saturated during lamp operation. A suitable ratio of the inner 5, 6 diameter of the outer envelope to the outer diameter of the discharge vessel is 3:l to L05: l; the diameter difference being smaller than 2 cm.
18 Claims, 6 Drawing Figures PATENTEDm 9 I972 3. 662.203
SHEEI 1 BF 5 DrBernhard KiJhl Alexander Dobrusskin INVENTORS ATTORNEYS MAY 9 I372 SHEU 2 0F 5 T "C l arc tube 1 DYJB 10 10 10' [Torr] FIG. 2a
Dr. Bernhard Kiiht Alexander Dobrusskin I NVEN TORS ATTORN El.
PATENTEUMY 9l972 3.662.203
sum 3 0F 5 HG. 2b
Dr. Bernhard KUhl Alexander Dobrusskin l NVENTORS MM 1: PM? BY AT TORNEYS PATENTEU SHEET & BF 5 Dr. Bernhard KLihl Alexander Dobrusskin INVENTOFG ILL M PATENTEDMY 9:912 3. 662.203
sum 5 er 5 FIG.5
FIGA
Dr. Bernhard Kijhl Alexander Dobrusskin BY AT TORN EYS HIGH PRESSURE SATURATED METAL VAPOR, PREFERABLY SODIUM OR METAL HALIDE VAPOR DISCHARGE LAMP The invention relates to a high pressure discharge lamp using an essentially saturated metal, or metal halide vapor, preferably a sodium vapor or a metal halide vapor discharge lamp with its discharge vessel, the so-called arc tube, hermetically sealed in an outer envelope.
in known lamps of this type the arc tube is enclosed in a single-ended ellipsoidal (see German Pat. No. |,l84,008) or single-ended cylindrical envelope of hard glass. The volume of the outer envelope is a multiple of the volume of the discharge vessel, and the ratio of diameter of outer envelope to diameter of arc tube is relatively large, for instance, in a metal halide vapor discharge lamp with a wattage input of 400 W, larger than six.
It is an object of the invention to improve lamps of the saturated metal and metal halide discharge type.
SUBJECT MATTER OF THE INVENTION:
The relative sizes of the envelope and are tube are changed so that the ratio of inner diameter of the outer envelope to outer diameter of the arc tube is substantially less, that is from 3:1 to I .05zl. The outer envelope is of thermally highly loadable material capable of withstanding a temperature exceeding 500 C, such as quartz glass. It encloses the discharge vessel comparatively closely without however coming in contact with the latter. The discharge vessel, likewise, is of thermally highly loadable material. The temperature of the outer envelope is increased in operation; in consequence of heat radiation from the outer envelope, additional heating of the arc tube is effected and thus the vapor pressure increase in the discharge. This is of special advantage for high pressure sodium vapor and metal halide vapor lamps which, in operating condition, have essentially saturated metal or metal halide vapors, because in these lamps an increase in vapor density is additionally caused, apart from the increase in vapor pressure. With suitably selected additives the color quality of the light is additionally improved resulting in outstanding color rendition by the lamps when in use. In high pressure mercury vapor discharge lamps, without additives, an increase in vapor pressure would also be obtained by an increase of the wall temperature of the arc tube; however, no increase in vapor density is obtained, because the mercury vapor pressure in these lamps is unsaturated.
The outer envelope has to be made from a material which can be highly stressed thermally. A cylindrical tube of quartz glass is suitable. Photometrically, an envelope of sapphire would be even better. Costs make such material uneconomical; increasing the temperature of the arc tube beyond certain ranges does not proportionately increase light output.
Due to the small difference between outer diameter of arc tube and inner diameter of outer envelope which is generally less than 20 mm, the outer envelope is preferably made in double-ended form. The outer envelope is closed at each end by a pinch seal preferably of l-type cross-section, enveloping the lead-in wires. The bases of insulating material, for example, of a ceramic material, are so shaped that one of its ends is provided with a slotted cylindrical portion. The legs of the base resulting therefrom are closely embracing the flat midsection of the pinch-seal. The lead-in wire is guided to the exterior by way of a contact pin passed through the base. Both bases of the outer envelope may be located in the direction of the lamp axis; or in order to obtain a reduction in lamp length, at least one of the bases of the outer envelope can be mounted at right angle to the lamp axis, an arrangement which is advantageous primarily in lamps of high wattage input, for example, 5 kW.
The inner wall surface of the outer envelope may be provided with an infrared (IR) radiation reflective coating of, for example, tin oxide; IR-radiation absorbing additives in the material of the outer envelope proved likewise suitable. Similar measures are also applicable for absorption of shortwave UV radiation and thus for suppression of objectionable formation of ozone, for example, coating with, or addition of TiO,.
The invention will be described by way of example with reference to the accompanying drawings, wherein:
FIG. 1 is a schematic cross-sectional view of the structure of a 400 W metal halide vapor discharge lamp;
FIG. 2a is a graph showing the luminous efficiency (ordinate) of a 400 W discharge lamp containing dysprosium iodide plotted against temperature (C) and vapor pressure FIG. 2b shows a section of the color triangle wherein the chromaticity coordinates of the light are shown for a lamp either with quartz or glass envelope;
H6. 3 is a schematic elevation of the structure of a 400 W high pressure sodium vapor discharge lamp;
FIG. 4 is a schematic view of a lamp having one base extending at right angle, and
FIG. 5 is a fragmentary cross-sectional view of a lamp base.
HO. 1: the discharge vessel 1 of quartz glass is sealed at its opposite ends by a pinch seal 2, 3 each, through which the lead-in wires 4, 5 are passed in vacuum-tight manner. The filling of the lamp comprises, for example, 20 mg of Hg, 2.5 mg of Dy, 10 mg of Hgh, 5.5 mg of TH and Ar at 30 torr in a volume of 16 cc. The end portions of the discharge vessel 1 are provided with a radiant-heat reflecting coating 6 of 21 02. The ends of the lead-in wires 4, 5 extending outside the discharge vessel 1 are electrically connected with a disk 7 of metal, for example, of nickel or molybdenum. The disk 7 has at its periphery a plurality of supports 8 which are used as resilient mounting support of the discharge vessel 1 in the enclosing outer envelope 9 of quartz glass. The inner surface may be coated as schematically shown at 9', with an IR, or UV (or both) reflective coating. One conductor 10 or ll, respectively, is connected to the lead-in wires 4, 5 via disk 7, said conductors extending hermetically sealed, through the ends of the outer envelope by means of flat pinch seals 12 or 13. The ceramic bases l4, 15 are affixed to the pinch seals l2, l3. l6 denotes the getter material provided within the outer envelope. The outer envelope 9 may either be exhausted or filled with nitrogen or argon of about 700 torr cold pressure. Suitable dimensions for a 400 W lamp:
the inner diameter of outer envelope 9 is 27 mm;
the outer diameter of discharge vessel 1 is 22.5 mm
(so that the two vessels are spaced by distance of 2.25 mm); Overall length of complete lamp:
about 20 cm.
If the lamp is operated in horizontal position with a wattage input of 400 W and an operating voltage of about l05 V, it has a luminous efficiency of about 70 lm/W. If operated in vertical position, the luminous efficiency is approx. lm/W.
In a lamp having a wattage input of 5 kW, suitable dimensions are:
outer envelope 9 has an inner diameter of 50 mm;
the discharge vessel 1 and outer diameter of 35 mm (so that the spacing between the two vessels is 7.5 mm); Overall lamp length of 65-70 cm is reduced by passing one of the lead-in wires laterally out of the outer envelope to about 50 cm.
The luminous efficiency of such a lamp is lm/W in horizontal operating position.
The curve shown in FIG. 20 applies to 400 W lamps with a constant arc tube wall load of 10 W/cm. Point A indicates the luminous efl'lciency 1 for a lamp with an ellipsoidal outer envelope of glass, point B for a lamp with an outer envelope of quartz according to the invention. Left of dashed limit line G, glass may still be used (for thermal reasons) as the material for the outer envelope, whereas to the right of limit line G up to border line Q, quartz should be used. Beyond limit line Q. higher thermally loadable materials should be used which may, however, due to their cost, be uneconomical commercially. in the section of the color triangle shown in FIG. 2b, the displacement of the chromaticity coordinates towards Plancks curve which is replaced within this range by curve RD of the daylight phase representing reconstituted daylight is clearly seen. A displacement in that direction is desirable because the color and color rendition of a light source is thereby improved. Point A, applies to a lamp with ellipsoidal outer envelope of glass, point B to a lamp with an outer envelope of quartz according to the invention. The border lines G and indicate similar to FIG. 20 the ranges of applicability of glass and quartz.
FIG. 3: the discharge vessel 17 of the high pressure sodium vapor discharge lamp is of light-transmissive alumina ceramic; its ends 18 and 19 are hermetically sealed in known manner. As is well known, the filling comprises sodium, mercury and a basic gas, for example, xenon or argon. The mounting support of the discharge vessel and the feed through of the lead-in wires are similar to the embodiment of FIG. 1 and have been given the same reference numbers. The inner diameter of the outer envelope 9 is 20 mm, the outer diameter of the discharge vessel 17 is 9 mm, so that the two vessels are spaced a distance of 5.5 mm. The complete lamp has an overall length of about 20 cm. The wattage input of the lamp is 400 W, the luminous efficiency about 100 lm/W.
Apart from the already disclosed advantages of considerably increased luminous efficiency, color improvement and outstanding color rendition, further advantages of the lamps according to the invention are obvious. In addition to the reduced costs of manufacture most marked in lamps of lower wattage input the lamps are perfectly suited for use in reflectors due to their base construction ensuring good adjustability. Because of the small dimensions, high intensity discharge lamps of this type are well suited for use in conjunction with search lights, headlights, projectors and the like. Incorporation into lighting fixtures intended for halogen incandescent lamps is likewise possible. The double-ended structure permits ignition of the lamp even under hot operating conditions by means of ignition devices with high starting pulses (30 kV) which is impossible in case of single-ended lamps due to the possibility of spurious arc-over caused by the small spacings at the base, lamp socket and fixture.
FIG. 4 shows a kW lamp with conventional cylindrical seals having an outer envelope 9, and in-line base 20 and a base 2l at the other end of the lamp extending at right angle with respect to the center line or axis C of the lamp. Of course, if desired, and as required by design of the fixture with which the lamp is to be used, both bases 20, 21 can be of the angle type.
H6. 5 is a cross-sectional view taken along lines VV of FIG. 3 of a base and the lamp foot. The press 12 of the lamp is an I cross-section, with a foil type electrode lead embedded and sealed therein. Two legs 22, 23 of a slotted base portion 14 embrace the l-shaped press.
We claim:
1. High pressure metal vapor discharge lamp with saturated vapor in operating condition of the lamp comprising:
a discharge vessel (1) of thermally highly loadable material permitting an operating temperature exceeding 500 C confining an arc-type discharge and forming an arc enclosing tube, and having a wall load exceeding 10 W/cm;
a double ended cylindrical outer envelope (9) of thermally highly loadable material permitting an operating temperature exceeding 500 C and enclosing said discharge vessel;
the spacing between the inner diameter of the outer envelope (9) and the outer diameter of the discharge vessel 1) being defined by a ratio of from 3:1 to 1.05:] to provide radiation of heat from the discharge within the discharge vessel (1) to the outer envelope (9) and radiation back of such heat towards the discharge vessel (1) to additionally heat said vessel to the extent that vapor density is additionally increased apart from the increase in vapor pressure.
2. Lamp as claimed in claim 1 wherein the difference between outer diameter of the arc tube and inner diameter of the outer envelope is less than 20 mm.
3. Lamp as claimed in claim I wherein a pinch seal (l2, 13)
is provided at each end of the outer envelope, said pinch seal being of l-shape in cross-section.
4. Lamp as claimed in claim 3 including a substantially cylindrical base of insulating material with slotted end portion constituting two opposed legs (22, 23) which closely embrace the flat mid-section of the pinch seal.
5. Lamp as claimed in claim 1 wherein the two bases of the outer envelope are extending in the direction of the lamp axis.
6. Lamp as claimed in claim I wherein at least one of the bases of the outer envelope is mounted at right angle to the lamp axis.
7. Lamp as claimed in claim 1 wherein the inner wall surface of the outer envelope (9) is provided with an infrared reflecting coating (9).
8. Lamp as claimed in claim 1 wherein the material of the outer envelope comprises [R-absorbing additives.
9. Lamp as claimed in claim I wherein the outer envelope (9) is provided with a coating reducing UV-radiation (9).
l0. Lamp as claimed in claim I wherein the material of the outer envelope comprises UV-absorbing additives.
ll. Lamp as claimed in claim 1 for 400 W input, wherein the discharge vessel has an outer diameter of about 2% cm and the outer envelope has an inner diameter of between 2% to 3 cm.
12. Lamp as claimed in claim I for 5 kW input, wherein the discharge vessel has an outer diameter of about 3% cm and the outer envelope has an inner diameter of about 5 cm.
13. Lamp as claimed in claim 1, wherein the discharge vessel contains halides of metal.
14. Lamp as claimed in claim 1, wherein the discharge vessel contains sodium.
15. Lamp as claimed in claim 14 for 400 W input, wherein the discharge vessel has an outer diameter of up to about I cm and the outer envelope an inner diameter of about 2 cm.
16. Lamp as claimed in claim 1, wherein the material of the outer envelope (9) is quartz glass.
17. Lamp as claimed in claim 1, wherein the material of the discharge vessel (1) is quartz glass.
18. Lamp as claimed in claim 1, wherein the material of the discharge vessel is lighttransmissive alumina ceramic.

Claims (17)

  1. 2. Lamp as claimed in claim 1 wherein the difference between outer diameter of the arc tube and inner diameter of the outer envelope is less than 20 mm.
  2. 3. Lamp as claimed in claim 1 wherein a pinch seal (12, 13) is provided at each end of the outer envelope, said pinch seal being of I-shape in cross-section.
  3. 4. Lamp as claimed in claim 3 including a substantially cylindrical base of insulating material with slotted end portion constituting two opposed legs (22, 23) which closely embrace the flat mid-section of the pinch seal.
  4. 5. Lamp as claimed in claim 1 wherein the two bases of the outer envelope are extending in the direction of the lamp axis.
  5. 6. Lamp as claimed in claim 1 wherein at least one of the bases of the outer envelope is mounted at right angle to the lamp axis.
  6. 7. Lamp as claimed in claim 1 wherein the inner wall surface of the outer envelope (9) is provided with an infrared reflecting coating (9'').
  7. 8. Lamp as claimed in claim 1 wherein the material of the outer envelope comprises IR-absorbing additives.
  8. 9. Lamp as claimed in claim 1 wherein the outer envelope (9) is provided with a coating reducing UV-radiation (9'').
  9. 10. Lamp as claimed in claim 1 wherein the material of the outer envelope comprises UV-absorbing additives.
  10. 11. Lamp as claimed in claim 1 for 400 W input, wherein the discharge vessel has an outer diameter of about 2 1/4 cm and the outer envelope has an inner diameter of between 2 1/2 to 3 cm.
  11. 12. Lamp as claimed in claim 1 for 5 kW input, wherein the discharge vessel has an outer diameter of about 3 1/2 cm and the outer envelope has an inner diameter of about 5 cm.
  12. 13. Lamp as claimed in claim 1, wherein the discharge vessel contains halides of metal.
  13. 14. Lamp as claimed in claim 1, wherein the discharge vessel contaIns sodium.
  14. 15. Lamp as claimed in claim 14 for 400 W input, wherein the discharge vessel has an outer diameter of up to about 1 cm and the outer envelope an inner diameter of about 2 cm.
  15. 16. Lamp as claimed in claim 1, wherein the material of the outer envelope (9) is quartz glass.
  16. 17. Lamp as claimed in claim 1, wherein the material of the discharge vessel (1) is quartz glass.
  17. 18. Lamp as claimed in claim 1, wherein the material of the discharge vessel is light-transmissive alumina ceramic.
US36318A 1969-05-20 1970-05-11 High pressure saturated metal vapor, preferably sodium or metal halide vapor discharge lamp Expired - Lifetime US3662203A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19696920340 DE6920340U (en) 1969-05-20 1969-05-20 HIGH PRESSURE DISCHARGE LAMP.
DE19691957978 DE1957978C3 (en) 1969-11-18 1969-11-18 High pressure sodium vapor or halogen metal vapor discharge lamp

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US3662203A true US3662203A (en) 1972-05-09

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US (1) US3662203A (en)
BE (1) BE750668A (en)
FR (1) FR2043549A1 (en)
GB (1) GB1305065A (en)
SE (1) SE374454B (en)

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US3780328A (en) * 1971-12-30 1973-12-18 Electronic Control & Surveilla Lighting unit for use underwater and in wet environment
US3842307A (en) * 1971-02-11 1974-10-15 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh High pressure mercury vapor discharge lamp with metal halide additives
US3889142A (en) * 1974-03-25 1975-06-10 Gte Sylvania Inc Metal halide discharge lamp having heat reflective coating
US3896326A (en) * 1973-07-19 1975-07-22 Gte Sylvania Inc Metal halide discharge lamp having expanded section arc tube
US3959524A (en) * 1974-03-25 1976-05-25 Gte Sylvania Incorporated Metal halide discharge lamp having heat reflective coating
EP0062381A1 (en) * 1981-04-08 1982-10-13 Koninklijke Philips Electronics N.V. High-pressure discharge lamp
FR2513809A1 (en) * 1981-09-28 1983-04-01 Gen Electric HIGH INTENSITY DISCHARGE LAMP
US4467238A (en) * 1981-09-03 1984-08-21 General Electric Company High-pressure sodium lamp with improved IR reflector
US4481446A (en) * 1979-04-26 1984-11-06 Mitsubishi Denki Kabushiki Kaisha Metal vapor discharge lamp
US4737677A (en) * 1984-11-30 1988-04-12 Gte Products Corporation Linear sodium lamp arc tube centering means
DE3735523A1 (en) * 1986-10-20 1988-04-28 Tungsram Reszvenytarsasag ALKALI HALOGENIDE AS AN ADDITIONAL METAL HALOGEN DISCHARGE LAMP
EP0279249A2 (en) * 1987-02-20 1988-08-24 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
EP0321867A2 (en) * 1987-12-22 1989-06-28 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
EP0321866A2 (en) * 1987-12-22 1989-06-28 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
US5111104A (en) * 1989-12-11 1992-05-05 Gte Products Corporation Triple-enveloped metal-halide arc discharge lamp having lower color temperature
US5272407A (en) * 1991-12-18 1993-12-21 North American Philips Corporation Electric lamp having screens for reducing photo electron emission
WO1995019639A1 (en) * 1994-01-18 1995-07-20 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Metal halide lamp
US5587626A (en) * 1993-12-10 1996-12-24 General Electric Company Patterned optical interference coatings for only a portion of a high intensity lamp envelope
DE29817633U1 (en) * 1998-10-02 2000-02-17 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Electric lamp with a base on one side
US6498429B1 (en) * 1999-11-15 2002-12-24 General Electric Company Sodium-xenon lamp with improved characteristics at end-of-life
EP1298704A2 (en) * 2001-09-29 2003-04-02 Chow, Shing Cheung Cold cathode fluorescent lamp with a double-tube construction
US6639341B1 (en) * 1999-03-26 2003-10-28 Matsushita Electric Works, Ltd. Metal halide discharge lamp
US20030209986A1 (en) * 1997-06-06 2003-11-13 Harison Toshiba Lighting Corporation Metal halide discharge lamp, lighting device for metal halide discharge lamp, and illuminating apparatus using metal halide discharge lamp
WO2006003601A1 (en) * 2004-06-29 2006-01-12 Koninklijke Philips Electronics N.V. Electric lamp and method for mounting a lamp vessel in an outer bulb
US20060255741A1 (en) * 1997-06-06 2006-11-16 Harison Toshiba Lighting Corporation Lightening device for metal halide discharge lamp
US20060273728A1 (en) * 2003-09-11 2006-12-07 Koninklijke Philips Electrnics N.V. High-pressure gas discharge lamp
US20080048541A1 (en) * 2004-12-20 2008-02-28 Sumrall Ernest N Polymer-thermal shield for ultra-violet lamp
US20080170384A1 (en) * 2007-01-11 2008-07-17 Zhu Jing Jim Lamp
US20090289551A1 (en) * 2006-07-07 2009-11-26 Koninklijke Philips Electronics N.V. Gas-discharge lamp
US20120262792A1 (en) * 2011-04-15 2012-10-18 Applied Botanics, Inc. Dba Method Seven Optical glass filter for producing balanced white light from a high pressure sodium lamp source
WO2015168559A1 (en) * 2014-05-02 2015-11-05 Surna, Inc. Modular stepped reflector
US10113343B2 (en) 2014-05-02 2018-10-30 Surna Inc. Thermally isolated high intensity light source
US10211042B2 (en) * 2016-12-04 2019-02-19 Allstate Garden Supply Double-ended high intensity discharge lamp and manufacturing method thereof

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US5075588A (en) * 1990-12-06 1991-12-24 Gte Products Corporation Arc discharge lamp with spring-mounted arc tube and shroud
DE10325552A1 (en) * 2003-06-05 2004-12-23 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Electric lamp with outer bulb has carrying body to which getter material is applied; carrying body is curved carrying band for mounting in bulb without auxiliary arrangement

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Cited By (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3842307A (en) * 1971-02-11 1974-10-15 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh High pressure mercury vapor discharge lamp with metal halide additives
US3780328A (en) * 1971-12-30 1973-12-18 Electronic Control & Surveilla Lighting unit for use underwater and in wet environment
US3896326A (en) * 1973-07-19 1975-07-22 Gte Sylvania Inc Metal halide discharge lamp having expanded section arc tube
US3889142A (en) * 1974-03-25 1975-06-10 Gte Sylvania Inc Metal halide discharge lamp having heat reflective coating
US3959524A (en) * 1974-03-25 1976-05-25 Gte Sylvania Incorporated Metal halide discharge lamp having heat reflective coating
US4481446A (en) * 1979-04-26 1984-11-06 Mitsubishi Denki Kabushiki Kaisha Metal vapor discharge lamp
EP0062381A1 (en) * 1981-04-08 1982-10-13 Koninklijke Philips Electronics N.V. High-pressure discharge lamp
US4479071A (en) * 1981-04-08 1984-10-23 U.S. Philips Corporation High-pressure discharge lamp having shielding means comprised of boron nitride
US4467238A (en) * 1981-09-03 1984-08-21 General Electric Company High-pressure sodium lamp with improved IR reflector
US4446397A (en) * 1981-09-28 1984-05-01 General Electric Company High intensity discharge lamp with infrared reflecting means for improving efficacy
FR2513809A1 (en) * 1981-09-28 1983-04-01 Gen Electric HIGH INTENSITY DISCHARGE LAMP
US4737677A (en) * 1984-11-30 1988-04-12 Gte Products Corporation Linear sodium lamp arc tube centering means
DE3735523A1 (en) * 1986-10-20 1988-04-28 Tungsram Reszvenytarsasag ALKALI HALOGENIDE AS AN ADDITIONAL METAL HALOGEN DISCHARGE LAMP
EP0279249A2 (en) * 1987-02-20 1988-08-24 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
US4837477A (en) * 1987-02-20 1989-06-06 Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh High pressure discharge lamp with improved arc tube retention structure
EP0279249A3 (en) * 1987-02-20 1990-08-29 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh High-pressure discharge lamp
EP0321867A2 (en) * 1987-12-22 1989-06-28 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
EP0321866A2 (en) * 1987-12-22 1989-06-28 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
EP0321866A3 (en) * 1987-12-22 1990-12-27 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh High-pressure discharge lamp
EP0321867A3 (en) * 1987-12-22 1991-01-02 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH High-pressure discharge lamp
US5111104A (en) * 1989-12-11 1992-05-05 Gte Products Corporation Triple-enveloped metal-halide arc discharge lamp having lower color temperature
US5272407A (en) * 1991-12-18 1993-12-21 North American Philips Corporation Electric lamp having screens for reducing photo electron emission
US5676579A (en) * 1993-12-10 1997-10-14 General Electric Company Patterned optical interference coatings for electric lamps
US5587626A (en) * 1993-12-10 1996-12-24 General Electric Company Patterned optical interference coatings for only a portion of a high intensity lamp envelope
WO1995019639A1 (en) * 1994-01-18 1995-07-20 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Metal halide lamp
US5854535A (en) * 1994-01-18 1998-12-29 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh Metal halide discharge lamp with a quartz discharge vessel and an outer UV radiation absorbent envelope
US20050179391A1 (en) * 1997-06-06 2005-08-18 Harison Toshiba Lighting Corporation Lightening device for metal halide discharge lamp
US20060255741A1 (en) * 1997-06-06 2006-11-16 Harison Toshiba Lighting Corporation Lightening device for metal halide discharge lamp
US20030209986A1 (en) * 1997-06-06 2003-11-13 Harison Toshiba Lighting Corporation Metal halide discharge lamp, lighting device for metal halide discharge lamp, and illuminating apparatus using metal halide discharge lamp
US7057349B2 (en) 1997-06-06 2006-06-06 Harison Toshiba Lighting Corporation Lightening device for metal halide discharge lamp
US6873109B2 (en) * 1997-06-06 2005-03-29 Harison Toshiba Lighting Corporation Metal halide discharge lamp, lighting device for metal halide discharge lamp, and illuminating apparatus using metal halide discharge lamp
DE29817633U1 (en) * 1998-10-02 2000-02-17 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Electric lamp with a base on one side
US6639341B1 (en) * 1999-03-26 2003-10-28 Matsushita Electric Works, Ltd. Metal halide discharge lamp
US6498429B1 (en) * 1999-11-15 2002-12-24 General Electric Company Sodium-xenon lamp with improved characteristics at end-of-life
US20030062822A1 (en) * 2001-09-29 2003-04-03 Chow Shing Cheung Cold cathode fluorescent lamp with a double-tube construction
US6815883B2 (en) * 2001-09-29 2004-11-09 Shing Cheung Chow Cold cathode fluorescent lamp with a double-tube construction
EP1298704A2 (en) * 2001-09-29 2003-04-02 Chow, Shing Cheung Cold cathode fluorescent lamp with a double-tube construction
EP1298704A3 (en) * 2001-09-29 2005-06-29 Chow, Shing Cheung Cold cathode fluorescent lamp with a double-tube construction
US20060273728A1 (en) * 2003-09-11 2006-12-07 Koninklijke Philips Electrnics N.V. High-pressure gas discharge lamp
US20080278050A1 (en) * 2004-06-29 2008-11-13 Koninklijke Philips Electronics, N.V. Electric Lamp and Method For Mounting a Lamp Vessel in an Outer Bulb
WO2006003601A1 (en) * 2004-06-29 2006-01-12 Koninklijke Philips Electronics N.V. Electric lamp and method for mounting a lamp vessel in an outer bulb
US20080048541A1 (en) * 2004-12-20 2008-02-28 Sumrall Ernest N Polymer-thermal shield for ultra-violet lamp
US7884549B2 (en) * 2006-07-07 2011-02-08 Koninklijke Philips Electronics N.V. Gas-discharge lamp
US20090289551A1 (en) * 2006-07-07 2009-11-26 Koninklijke Philips Electronics N.V. Gas-discharge lamp
US20080170384A1 (en) * 2007-01-11 2008-07-17 Zhu Jing Jim Lamp
US20120262792A1 (en) * 2011-04-15 2012-10-18 Applied Botanics, Inc. Dba Method Seven Optical glass filter for producing balanced white light from a high pressure sodium lamp source
WO2015168559A1 (en) * 2014-05-02 2015-11-05 Surna, Inc. Modular stepped reflector
US10113343B2 (en) 2014-05-02 2018-10-30 Surna Inc. Thermally isolated high intensity light source
US10211042B2 (en) * 2016-12-04 2019-02-19 Allstate Garden Supply Double-ended high intensity discharge lamp and manufacturing method thereof

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Publication number Publication date
BE750668A (en) 1970-11-03
FR2043549A1 (en) 1971-02-19
SE374454B (en) 1975-03-03
GB1305065A (en) 1973-01-31

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