US2965789A - Vapor pressure control in discharge lamps - Google Patents

Vapor pressure control in discharge lamps Download PDF

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Publication number
US2965789A
US2965789A US729425A US72942558A US2965789A US 2965789 A US2965789 A US 2965789A US 729425 A US729425 A US 729425A US 72942558 A US72942558 A US 72942558A US 2965789 A US2965789 A US 2965789A
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US
United States
Prior art keywords
lamp
envelope
groove
vapor pressure
pressure control
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
Application number
US729425A
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English (en)
Inventor
Lemmers Eugene
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to NL238268D priority Critical patent/NL238268A/xx
Application filed by General Electric Co filed Critical General Electric Co
Priority to US729425A priority patent/US2965789A/en
Priority claimed from US734569A external-priority patent/US2973447A/en
Priority to US734551A priority patent/US2950410A/en
Priority to GB11039/59A priority patent/GB929618A/en
Priority to FR792378A priority patent/FR75582E/fr
Priority to DEG26881A priority patent/DE1123047B/de
Priority to FR794044A priority patent/FR76208E/fr
Priority to FR794042A priority patent/FR75708E/fr
Publication of US2965789A publication Critical patent/US2965789A/en
Application granted granted Critical
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • H01J61/33—Special shape of cross-section, e.g. for producing cool spot

Definitions

  • This invention relates generally to mercury vapor pressure control in electric discharge lamps having elongated tubular envelopes and more particularly in noncircular lamps of grooved or kidney-shaped cross section.
  • a transversely re-entrant groove extends longitudinally in continuous fashion along one side of the envelope.
  • comparatively short sections of groove are provided alternating on opposite sides of the envelope.
  • the longitudinal groove extends intermittently along'one side and is interrupted at several places by regions of circular cross section for increasing the strength of the envelope against implosion by reason of external atmospheric pressure.
  • a re-entrant or grooved cross section achieves a high ratio of perimeter to area of the cross section along with a relatively high implosion resistance. This is highly advantageous in resonance radiation lamps, for instance in fluorescent lamps utilizing the resonance radiation of mercury vapor at 2537 A. to excite a phosphor coated internally on the walls of the envelope in order to produce visible light, and achieves higher loading and lumen output per unit axial length at a given eificiency than heretofore possible.
  • a high electron speed is obtained simultaneously with reduced elastic collision losses due to more rapid diffusion of electrons, mercury ions and radiation quanta to the bulb walls, thereby improving the rate of delivery of 2537 A. radiation to the bulb walls.
  • the lamp current is less and the lamp voltage higher than with lamps of equal periphery in a circular cross section, thereby reducting both the cathode losses and ballast losses.
  • An object of the invention is to provide a grooved discharge lamp having a new and improved vapor pressure regulating feature.
  • Another object of the invention is to provide a vapor pressure regulating center in a re-entrant groove lamp which is convenient and economical to manufacture and which does not require any special care of maintenance in operation of the lamp or in its handling in order to avoid breakage or damage.
  • a metal vapor pressure regulating center is provided by forming the vitreous envelope of the lamp at places contiguous to one or more of the grooves to a contour which exludes or at least reduces the intensity of the discharge in selected regions. These regions as a result run cooler and serve as vapor pressure control centers.
  • the special forms given to the glass envelope walls are so disposed that where they project outwardly from what would otherwise be the contour of the lamp, they are located entirely within one of the recessed grooves. Thus there are no projections beyond the general cylindrical configuration of the lamp so that the danger of breaking such projections during manufacture or susequent handling is eliminated.
  • one or more of the re-entrant grooves are provided with an upstanding fin extending outwardly from the bottom wall of the groove.
  • the fin is relatively narrow so that the plasma or discharge does not penetrate into it and as a result it remains relatively cool. Being entirely located within the re-entrant groove, the fin does not project beyond the generally cylindrical con-figuration of the lamp so that it is not readily subject to breakage.
  • a depression or indentation is provided on one side of the bottom or inner wall of the groove and projects inwardly into the envelope space. This causes the plasma or discharge to be excluded from the space between the indentation and the near edge Wall on one side of the groove. Accordingly that region of the, edge wall is cooled and serves as a mercuryvapor pressure control center.
  • Fig. 1 is a pictorial view of a discharge lamp embodying a preferred form of the invention, portions of the envelope wall being removed to shorten the figure.
  • Fig. 2 is a transverse cross sectional view of the lamp in the plane 2-2 of Fig. 1.
  • Fig. 3 ' is a side sectional view of the lamp taken in the plane 3-3 of Fig. 2.
  • Fig. 4 is a'transverse cross sectional view of another lamp embodying another formof the inventionJ
  • Fig. 5 is a side sectional view of the lamp of Fig. 4 takenin the plane 5 -5.
  • a fluores cent lamp of the low-pressure positive column type comprising an elongated vitreous envelope 1.
  • the envelope is provided with circular or round tube ends 2, 2 which are annularly reduced or shouldered at their extremities for securing thereto bases 3, 3.
  • an electrode mount or stem 4 is sealed into eachtube end.
  • a pair of lead wires 5, 5 are sealed through the stem and support on their inward projections a filamentary cathode 6 while their outward projections are connected to the contact pins 7, 7 of the base.
  • the cathode may consist of a coiled coil of tungsten wire provided with an overwind and coated with an activated mixture of alkaline earth oxides, such as the usual mixture comprising barium and strontium oxides.
  • the lamp contains an ionizable atmosphere including a starting gas or mixture of one or more of the inert rare gases of group of the periodic table at a low pressure,'for' instance argon at a pressure of 0.5 to millimeters of mercury or alternatively a mixture of argon and up to 20% neon in this range of pressure.
  • the mercury vapor is provided by a small quantity of mercury exceeding in amount the quantity vaporized during operation of the lamp wherein the mercury vapor may exert a partial pressure in the range of 1 to 20 microns for optimum generation of mercury resonance radiation at 2537 A.
  • a phosphor coating indicated at 8 on the inside of the envelope converts the 2357 A..radiation into visible light.
  • the envelope 1 is provided with spaced indentations or re-entrant portions 10, 11 on diametrically opposite sides giving a dimpled or crenelated appearance.
  • the indentations 10, 11 may be considered to be short sections of a longitudinal groove alternating on opposite sides of the envelope, and the lamp is sometimes referred to as doublegrooved.
  • the discharge cross section through the grooved sections of the lamp is in general kidney-shaped as illustrated in Fig. 2.
  • the resulting configuration has a high implosion resistance and maintains good efficiency at high loadings by reason of the higher electron velocities and reduced elastic collision losses. These characteristics are due of course to the more rapid diffusion of photons, electrons, and mercury ions to the walls as previously mentioned.
  • the discharge in these zones is constricted even as it is in the kidney-shaped cross section throughout the groove sections.
  • the discharge operates at a high efliciency even in these zones and furthermore the arc is lengthened by virtueof the zigzag path which it is constrained to follow. This further increases the. percentage of total lamp wattage going intorthe positive column relative to fixed electrode losses, thereby increasing the etficiency.
  • fins 15, 16 are shown in grooved sections 10' and 11'.
  • Fin has side walls rising upwardly from bottom wall 17 of the groove section and merging on one side. into into the sloping end wall 12'.
  • the fin does not extend all the way to the opposite end wall 12 of the groove but has a forward edge 18 sloping down to the bottom wall 17, and is symmetrically located along the medial line of the groove.
  • the width of the fin is'subs tantially less than the least dimension of the discharge cross section defined by the envelope walls elsewhere throughout the lamp, with the result that the plasma or discharge does not spread into it to any appreciable extent.
  • the fin in consequence runs much cooler than the remainder of the lamp and serves as a mercury vapor control center in which the excess mercury condenses. If desired the fin may extend the full length of the groove, that is from sloping end wall 12 to sloping end wall 12.
  • the fin may be formed by utilizing a split tool to press the groove section 10' wherein the fin is to be located.
  • T he pressing tool and the general technique may be similar to that described in aforementioned application Serial No. 578,772 of Lemmers et a1.
  • the lamp envelope is selectively heated in the zones where the grooved panels are to be formed until the glass becomes suitably plastic, and then a plunger or pressing bar with suitable protuberances is pressed down against the envelope.
  • the protuberances contact the glass in the heated zones and cause the envelope walls to fold inwardly in those zones thereby forming the reentrant cavities or grooves desired.
  • One or more of the protuberances in the pressing bar is split or channeled at one end forming a recess in which the glass wall of the envelope remains upstanding to form the fin 15. Suction may be applied to the recess to assist in maintaining the glass wall upstanding and in orderto cause it to conform to the recess.
  • the grooves on the opposite side of the envelope, and also additional fin 16 if desired, may be formed in like manner by rotating the envelope on its longitudinal axis and repeating the operation.
  • One or more of the groove sections located near the center of the lamp may be provided with a fin in order to provide several vapor pressure control centers whereby to accelerate the stabilization of the vapor pressure after the lamp is put in operation.
  • at least one groove section on each side of the envelope should be provided with a It will then be immaterial which grooved side of the lamp faces downwardly or outwardly to either side when the lamp'is installed in a fixture. Convection air currents will maintain the'lowest temperature in one or the other, of the fins, whichever one happens to be more favorably located and that one will serve as the mercury vapor pressure controlicenter.
  • fin 15 on one side of the lamp and fin 16 on the other may be formed to merge into adjacent sloping end walls 12', 13' of the grooves in a back-to-back relationship, as illustrated in Figs. 1 and 3, for improved symmetry.
  • the provision of fins permits the lamps to be operated at substantially higher loadings than heretofore while yet maintaining the mercury vapor pressure therein at the desired optimum for most efiicient generation of 2537 A. radiation.
  • the fins permit operation at 30 watts per foot at room temperature and provide a control temperature of approximately 40 C. 'for a mercury vapor pressure of approximately 6 microns, such being close to the optimum for this lamp.
  • FIGs. 4 and 5 there is shown another embodiment of the invention in a re-entrant groove lamp wherein 'the groove 21 is disposed entirely along one side in discontinuous sections with upstanding portions or bridges '22' of generally circular section in between.
  • the panels of the lamp where the groove provides'a kidney-shaped cross section are high efficiency regions as regards the production of light,
  • the entire lamp mayin general be similar to that shown in Fig. 1 and previously described as comprising activated filamentary electrodes sealed into opposite ends and a. filling ,of fan ionizable medium comprising a rare gas and mercury fine itself at that point to the region between the indentation and the remote edge Wall'or rail 24 of the kidneyshaped cross section.
  • the plasma assumes a generally lenticular cross section within this region as illustrated in dotted lines at 25. In the region indicated at 26 between indentation and near edge wall 24, the plasma or discharge does not penetrate.
  • this side of the lamp and particularly the edge wall or rail at 24 operate at a substantially lower temperature and serve as an effective mercury vapor pressure control center.
  • an indentation as illustrated in Figs. 4 and 5 may cause a drop in the temperature of the edge of the lamp of as much as 15 C. under what would otherwise be the temperature of the edge walls on either side of the groove.
  • the region between the indentation and the near edge wall thus serves as a vapor pressure control center allowing operation of the lamp at optimum vapor pressure for substantially higher loadings.
  • a low pressure electric discharge lamp comprising an elongated vitreous envelope having electrodes sealed into opposite ends and containing an ionizable medium including an inert starting gas and a metal vapor in equilibrium with an excess of non-vaporized metal, said vitreous envelope being entirely contained within a generally cylindrical boundary and having substantial longitudinally grooved portions, said envelope having at least one deformation in the wall contour of the groove within one of said grooved portions and located entirely within said cylindrical boundary, said deformation providing a constricted zone within the envelope which causes the discharge plasma to be substantially excluded therefrom, said zone thereby operating at a cooler temperature than the remainder of said envelope and serving as a metal vapor pressure control center.
  • a low pressure electric discharge lamp comprising an elongated vitreous envelope having electrodes sealed into opposite ends and containing an ionizable medium including an inert starting gas and mercury vapor in equilibrium with an excess of non-vaporized mercury, said vitreous envelope being entirely contained within a generally cylindrical boundary and having substantial longitudinally grooved portions of generally kidneyshaped cross section, said envelope having at least one deformation in the wall contour of the groove within one of said groove sections and located entirely within said cylindrical boundary, said deformation providing a constricted zone within the envelope and causing the discharge plasma to be substantially excluded therefrom, said zone thereby operating at a cooler temperature than the remainder of said envelope and serving as a mercury vapor pressure control center.
  • a low pressure electric discharge lamp comprising an elongated vitreous envelope having electrodes sealed into opposite ends and containing an ionizable medium including an inert starting gas and mercury vapor in equilibrium with an excess thereof in liquid form, said vitreous envelope being entirely disposed within a generally cylindrical boundary and having substantial portions kidney-shaped in cross section by means of a series of relatively short longitudinal grooves alternating on opposite sides and having sloping end walls, and at least one upstanding fin portion in one of said grooves, said fin portion extending outwardly from the bottom wall of the groove toward said cylindrical boundary and sloping to said bottom wall at one end and merging into the sloping end wall of the groove at the other end, said fin being relatively narrow in transverse dimension in order to exclude the electric discharge plasma therefrom, said fin thereby providing a zone operating at a cooler temperature than the remainder of the envelope and serving as a mercury vapor pressure control center.
  • a low pressure electric discharge lamp comprising an elongated vitreous envelope having electrodes sealed into opposite ends and containing an ionizable medium including an inert starting gas and mercury vapor in equilibrium with an excess thereof in liquid form, said vitreous envelope being entirely disposed within a generally cylindrical boundary and having substantial portions kidneyshaped in cross section by means of a series of relatively short longitudinal grooves alternating on opposite sides and having sloping end walls, and an upstanding fin portion in at least two of said grooves disposed on opposite sides of said envelope said fin portions extending outwardly from the bottom wall of the groove toward said cylindrical boundary and sloping to said bottom wall at one end and merging into the sloping end of the groove at the other end, said fins being relatively narrow in transverse dimension in order to exclude the electric discharge plasma therefrom, said fins thereby providing at least one zone operating at a cooler temperature than the remainder of the envelope and serving as a mercury vapor pressure control center irrespective of the position of the grooves in mounting the lamp.
  • a low pressure electric discharge lamp comprising an elongated vitreous envelope having electrodes sealed into opposite ends and containing an ionizable medium including an inert starting gas and mercury vapor in equilibrium with an excess thereof in liquid form, said vitreous envelope being entirely disposed within a generally cylindrical boundary and having substantial portions kidneyshaped in cross section by means of longitudinally extending re-entrant groove sections, and at least one additional indentation in the bottom wall of a groove section, said indentation being directed inwardly into the discharge space and located to one side of the medial line of the groove section whereby to provide a constricted zone between the indentation and the near edge wall on one side of the groove from which the discharge plasma is substantially excluded, said zone thereby operating at a cooler temperature than the remainder of the envelope and serving as a mercury vapor pressure control center.
  • a low pressure electric discharge lamp comprising an elongated vitreous envelope having electrodes sealed into opposite ends and containing an ionizable medium including an inert starting gas and mercury vapor in equione side of the medial line of the groove section whereby 10 to provide a constricted zone between the indentation and the near edge wall on one side of the groove from which the discharge plasma is substantially excluded, said zone thereby operating at a cooler temperature than the remainder of the envelope and serving as a mercury vapor pressure control center.

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  • Vessels And Coating Films For Discharge Lamps (AREA)
  • Discharge Lamp (AREA)
US729425A 1958-04-18 1958-04-18 Vapor pressure control in discharge lamps Expired - Lifetime US2965789A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
NL238268D NL238268A (fr) 1958-04-18
US729425A US2965789A (en) 1958-04-18 1958-04-18 Vapor pressure control in discharge lamps
US734551A US2950410A (en) 1958-04-18 1958-05-12 Multiple groove discharge lamp
GB11039/59A GB929618A (en) 1958-04-18 1959-04-01 Improvements in or relating to multiple-groove discharge lamps
FR792378A FR75582E (fr) 1958-04-18 1959-04-17 Enveloppes résistant à l'écrasement pour lampes tubulaires à décharge à basse pression ou à incandescence et lampes à décharge à rendement amélioré
DEG26881A DE1123047B (de) 1958-04-18 1959-04-20 Leuchtstofflampe fuer ueberhoehte Leistungsaufnahme
FR794044A FR76208E (fr) 1958-04-18 1959-05-06 Enveloppes résistant à l'écrasement pour lampes tubulaires à décharge à basse pression ou à incandescence, et lampes à décharge à rendement amélioré
FR794042A FR75708E (fr) 1958-04-18 1959-05-06 Enveloppes résistant à l'écrasement pour lampes tubulaires à décharge à basse pression, ou à incandescence et lampes à décharge à rendement amélioré

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US729425A US2965789A (en) 1958-04-18 1958-04-18 Vapor pressure control in discharge lamps
US73451158A 1958-05-12 1958-05-12
US734569A US2973447A (en) 1958-05-12 1958-05-12 Grooved lamp vapor pressure control

Publications (1)

Publication Number Publication Date
US2965789A true US2965789A (en) 1960-12-20

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US729425A Expired - Lifetime US2965789A (en) 1958-04-18 1958-04-18 Vapor pressure control in discharge lamps

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US (1) US2965789A (fr)
DE (1) DE1123047B (fr)
FR (2) FR75582E (fr)
GB (1) GB929618A (fr)
NL (1) NL238268A (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3121183A (en) * 1960-08-31 1964-02-11 Duro Test Corp Fluorescent lamp
US3331977A (en) * 1965-03-15 1967-07-18 Westinghouse Electric Corp High output discharge lamp with vapor pressure control means
WO2004032180A2 (fr) * 2002-10-04 2004-04-15 Koninklijke Philips Electronics N.V. Lampe a vapeur de mercure basse pression
WO2003085695A3 (fr) * 2002-04-11 2005-05-06 Koninkl Philips Electronics Nv Lampe a decharge a vapeur de mercure basse pression
US20050126274A1 (en) * 2002-04-17 2005-06-16 Martin Griesser Method for identifying tire characteristics
US7276853B2 (en) 2002-04-11 2007-10-02 Koninklijke Philips Electronics, N.V. Low-pressure mercury vapor discharge lamp

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2108916B1 (fr) * 1970-10-13 1973-11-30 Gerland Ste Chimique
JPS6276149A (ja) * 1985-09-28 1987-04-08 Toshiba Corp けい光ランプ装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2020726A (en) * 1932-10-01 1935-11-12 Gen Electric Gaseous electric discharge device
FR802714A (fr) * 1936-02-12 1936-09-14 Perfectionnements aux tubes luminescents
US2190009A (en) * 1937-05-22 1940-02-13 Boucher Inv S Ltd Luminescent tube and system
US2213245A (en) * 1935-12-23 1940-09-03 Germer Edmund Electrical discharge device
FR861799A (fr) * 1938-11-26 1941-02-17 Lampes Sa Perfectionnements aux dispositifs à décharge lumineuse
US2317265A (en) * 1940-07-26 1943-04-20 Foerste William Fluorescent lamp
US2501375A (en) * 1944-12-21 1950-03-21 Gen Electric Electric discharge lamp

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE556663A (fr) * 1954-12-14
AT199750B (de) * 1954-12-14 1958-09-25 Gen Electric Entladungslampe

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2020726A (en) * 1932-10-01 1935-11-12 Gen Electric Gaseous electric discharge device
US2213245A (en) * 1935-12-23 1940-09-03 Germer Edmund Electrical discharge device
FR802714A (fr) * 1936-02-12 1936-09-14 Perfectionnements aux tubes luminescents
US2190009A (en) * 1937-05-22 1940-02-13 Boucher Inv S Ltd Luminescent tube and system
FR861799A (fr) * 1938-11-26 1941-02-17 Lampes Sa Perfectionnements aux dispositifs à décharge lumineuse
US2317265A (en) * 1940-07-26 1943-04-20 Foerste William Fluorescent lamp
US2501375A (en) * 1944-12-21 1950-03-21 Gen Electric Electric discharge lamp

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3121183A (en) * 1960-08-31 1964-02-11 Duro Test Corp Fluorescent lamp
US3331977A (en) * 1965-03-15 1967-07-18 Westinghouse Electric Corp High output discharge lamp with vapor pressure control means
WO2003085695A3 (fr) * 2002-04-11 2005-05-06 Koninkl Philips Electronics Nv Lampe a decharge a vapeur de mercure basse pression
US7276853B2 (en) 2002-04-11 2007-10-02 Koninklijke Philips Electronics, N.V. Low-pressure mercury vapor discharge lamp
CN100380568C (zh) * 2002-04-11 2008-04-09 皇家飞利浦电子股份有限公司 低压汞蒸汽放电灯
US20050126274A1 (en) * 2002-04-17 2005-06-16 Martin Griesser Method for identifying tire characteristics
US7263878B2 (en) 2002-04-17 2007-09-04 Continental Teves Ag & Co. Ohg Method for identifying tire characteristics
WO2004032180A2 (fr) * 2002-10-04 2004-04-15 Koninklijke Philips Electronics N.V. Lampe a vapeur de mercure basse pression
WO2004032180A3 (fr) * 2002-10-04 2005-08-25 Koninkl Philips Electronics Nv Lampe a vapeur de mercure basse pression

Also Published As

Publication number Publication date
GB929618A (en) 1963-06-26
NL238268A (fr)
FR75582E (fr) 1961-07-17
DE1123047B (de) 1962-02-01
FR75708E (fr) 1961-08-04

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