CA1165800A - Halogen incandescent lamp - Google Patents
Halogen incandescent lampInfo
- Publication number
- CA1165800A CA1165800A CA000373372A CA373372A CA1165800A CA 1165800 A CA1165800 A CA 1165800A CA 000373372 A CA000373372 A CA 000373372A CA 373372 A CA373372 A CA 373372A CA 1165800 A CA1165800 A CA 1165800A
- Authority
- CA
- Canada
- Prior art keywords
- pinch
- lamp
- space
- internal current
- conductor
- 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
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01K—ELECTRIC INCANDESCENT LAMPS
- H01K1/00—Details
- H01K1/62—One or more circuit elements structurally associated with the lamp
- H01K1/66—One or more circuit elements structurally associated with the lamp with built-in fuse
Landscapes
- Vessels And Coating Films For Discharge Lamps (AREA)
Abstract
ABSTRACT:
A halogen incandescent lamp according to the invention comprises a built-in fuse. Within a pinch a space is formed through which a part of an internal current conductor to the filament extends so as to be circumferentially free from the quartz glass of the pinch. In an embodiment of the lamp the weld between the internal current conductor and the metal foil which as a current lead-through conductor is sealed in a vacuum-tight manner in the pinch is also situated in the space. The space is located beneath a boss on the surface of the pinch.
A halogen incandescent lamp according to the invention comprises a built-in fuse. Within a pinch a space is formed through which a part of an internal current conductor to the filament extends so as to be circumferentially free from the quartz glass of the pinch. In an embodiment of the lamp the weld between the internal current conductor and the metal foil which as a current lead-through conductor is sealed in a vacuum-tight manner in the pinch is also situated in the space. The space is located beneath a boss on the surface of the pinch.
Description
~5~
PHN ~719 1 11.11.lg8o "~Ialogen incandescent lamp".
The invention relates to a halogen incandescent lamp having a quartz glass lamp envelope, whose cavity is filled with a halogen-containing inert gas and in which a tungsten filament is accommodated~ which lamp envelope is sealed by means of a pinch in which at least one rnetal foil is embedded to whose respective ends an internal current conductor to the filament and an external curren-t conductor are welded, which lamp has a fuse accommodated in an en-closed space bounded by the pinch. Such a lamp is disclo-1~ sed in the United States Patent Specifica-tion 3,264,516.
In by far most of the cases, halogen incandescen-t lamps have a gas filling with a pressure of approxima-tely 1 bar or more which during operation increases by a factor of 4 or 5. When at the end of the life of such a lamp the filament or an internal current conductor fuses, a dischar-ge arc is formed in the lamp which produces a high current strength and can penetrate into the pinch. The rapid evapo-ration of the metal parts incorporated in the pinch then causes cracking of the pinch, the lamp exploding as a result of the high gas pressure. This process occurs so rapidly that the use of an external fuse does not prevent explosion of the lamp with certainty. In addition many luminaires do not have such a fuse.
In the lamp which is disclosed in the above-mentioned Uni-ted States Patent Specification, a hollow space adjoins the end of the pinch remote from the filamen-t and is closed by a second pinch~ ~ thin conductor extends in said space and is connected at orle end vla a -thicker conductor to the foil in the pinch of the lamp and at its other end is connected to a contac-t cap situated outside the lamp envelope. This thin conductor serves as a fuse.
The cons-truc-tion of the known lamp suffers from .~
P~IN 9719 2 11.11.1980 a number of disadvantages. The manufac-ture of the lamp is considerably more laborious than -that of lamps without a fuse. More componen-ts are used therein than in lamps without a fuse. The fuse wire should be very thin because otherwise a vacuum-tight second pinch canno-t be made around the wire due to the large differences in coeffi-cients of thermal expansion between quartz glass and me-tal.
However, a vacuum tight seal is necessary so as to prevent corrosion of the wire. The small diameter of the wire - a vacuum-tight seal is possible on wires up to approximately 1~0tum diameter - causes loss of energy. Wi-th an extra enclosed space for the fuse of 20 mm length and an e~tra pinch at the relevant end of the lamp envelope the con-struction produces a considerably longer lamp. Furthermoremeasures should be taken to prevent corrosion of the fuse wire in so far as it projects beyond the extra pinch.
It is -the object of -the inven-tion to provide a lamp having a built-in fuse in which said disadvantages are at least mitigated, more especially a lamp which, in spite of the presence of a built-in fuse, need no-t comprise more or different components than a comparable lamp without a fuse.
~ ccording to the invention this object is achieved in a lamp of the kind described in the opening paragraph in that the enclosed space is provided within the pinch such that a part of the internal current conduc-tor extends through the space so as to be cicumferentially free from the surrounding quartz glass of the pinch9 which part constitutes the fuse.
Quartz glass is -to be understood -to mean herein glass having a silicon dloxide content of a-t least ~/0 by weight.
If as a result of the fusing of the filament or an internal current conductor, a discharge arc is formed in the cavi-ty of the lamp envelope in which the filament is accommodated. As a result, the current through the lamp, and hence through the internal current conductor, increases PHN 9719 3 11. 11 . 1980 considerably. Since at least one internal current conductor is circumferentially free from the glass over a part of its length in the enclosed space within the pinch~
the heavy current through said in-ternal current conduc-tor 5 results in a la~ger rise in temperature than if said current conductor were embedded in the glass of t~e pinch and would hence be cooled by said glass. As a result of this the conductor fuses very rapidly. However, it has been found that no discharge arc is formed in the enclosed space with-lO in the pinch, possibly because the temperature in saidspace, which communicates with the cavity of the lamp enve-lope only via a narrow capillary duct which is inevitably formed during making the pinch, is much lower than in the cavity of the lamp envelope in which the filament is accommo l5 dated.
The weld o~ the internal current conduc-tor to the metal foil, which generally consists of tungsten or molyb-denum9 may be present beyond the enclosed space which is provided within the pinch. In an embodiment of the lamp in 20 accordance with the invention said weld, however, may be present in the enclosed space pro~idsd within the pinch.
Because it is di~ficult to weld tungsten wire to a tungsten or molybdenum foil, it is likely that, in rnanufacturing lamps, besides many good welds also a few bad welds are 25 obtained. As a result of the high contact resistance of bad welds, high temperatures may arise which lead to crack-ing of the pinch. In the last-mentioned ernbodiment of the lamp in accordance wi-th the invention, this danger is also avaided.
The lamp in accordance with the invention no-t only has the advantage that no additional par-ts are necessa ry as compared with non-safeguarded lamps and that the fuse is excluded from the ambient air by the vacuum-tlght seal of the lamp itself so tha-t air cannot cause corros:ion~ lt 35 also has the advan-tage that a varie-ty of constructions of internal current conductors wh:ich are in common use may be used. For example, the straight limb of a single coiled "~
PHN 9719 4 11.11.1980 cO
(sc.) filament or the single ~ limb of a coiled coil (c.c.) filament may be used as an internal current conduc-tor. On the other hand it is possible to construct the internal current conduc-tor as a straight wire wound helical_ ly at one or both ends or as an entirely helically wound wire which is screwed in or around one end o~ the ~ila-ment. In a coiled coil filament, fur-thermore, a single coiled limb may be slid over a straight wire and be attach-ed thereto by pinching or welding. In cases in which an internal curre.nt conductor is helically wound in the region where it is welded to the metal foil9 a straight piece of wire is of-ten inserted into the helix of the internal current conductor so as to facilitate the making of a weld with the metal foil. Such a piece of wire may be omitted in a construction in which a second layer of turns is provided on the helically wound internal current conduc-tor in the region where the weld is to be made. The second layer of turns may be formed from the same wire as the first layer. This may be the case both when the internal current conductor is the limb of the ~ilament, and also when the internal current conduc-tor is a separate compo-nent. An short even-t, when making the internal curren-t conduc-tor the winding wire, after having made -the first layer of -the -turns, is wound with opposite winding sense over the firs-t layer, after which, if desired9 a third layer of turns can be provided with the original winding sense. The advantage of this latter embodiment is that several intercoupled filaments can be obtained in a con-tinuous operation, ~hich f:ilaments are -then separated.
In lamps having a long computed li~e the danger exists that the par-t of the internal co:nductor extending in the cavity o~ the :Larnp enve:Lope is attaclced by -tho halogen of the gas f:illing. This attack may res-ult in s~-Lch a local reductl.on in diameter of the i.nternal curren-t con_ d-uc-tor tha-t the lamp e~tinguishes prematurely when said current conduc-tor fuses.
Lamps in accordance with the invention presen-t ]`~
P~IN 9719 5 11.11.19~0 the possibility o~ readily constructing the internal current conductor whilst nevertheless -taking into accound re~uirements which, dependen-t on the type o~ the lamp, are imposed on said current conductor ~or the sa-tis~ac-tory 5 operation of the lamp~ for example a minimum wire diame-ter for the said curren-t conductor. It has been found tha-t the wire diameter of the internal current conductor may be larger than the wire diameter of the filament so -that the number of hours in operation in which the internal conductor 10 is attacked to such an extent as to break or to fuse can be matched to the computed life of the ~ilament. For example with internal conductors having a 20% larger wire diameter than the wire diameter o~ the filament, a reliable fuse in lamps in accordance with the invention was nevertheless 15 obtained.
Since in the lamp in accordance with the invention the use of thinner than normal (i.e~ fusible) conductors, and the use of additional components can be avoided, mecha-nically strong lamps can be manufactured in a simple manner 20 and nevertheless have a built-in fusel The fuse construction of lamps in accordance with the invention makes it possible to construct the lamp as a mono-inch or as a two~inch lamp.
In mono-pinch lamps one or both internal current conductors to the filament may extend through the enclosed space provi-25ded within the pinch. In two~nch lamps~ both internalcurrent conductoxs ma-~A extend -through an enclosed space provided within the respective pinches.
The presence of an enclosed space within the pinch through which the internal current conductor extends 30so as to be circwnferentiall~ free from the glass o~ the pinch, is revea]ed by the presence of a local boss on the pinch surface. This is obtained by providing the pinching blocks with which the pinch is manu~actured with a recess.
The boss, and hence -the resulting enclosed space, preferably 35ex-tends substantially over the whole width o:~ the pinch so that the enclosed space is as large as possible witho-ut this involving any or an~ noteworthy increase o~` the overall length o~ the lamp.
PHN 9719 6 11.11.1980 It is to be noted that in lamps in accordance with the invention, as is always the case in lamps having a metal foil incorporated in the pinch as a current lead-through conductor, the vacuum-tight seal of the lamp envelope is realised in that zone of the pinch which is situated between the welds on the metal foil.
It is furthermore to be noted -that a lamp for general lighting purposes (GLS lamp) is described in British Patent Specification ~60.976, (published already in 1937) which lamp also has a fuse. The lamp has a con-struction which, e~cept for thefuse, is similar -to that of the curre~t GLS lamp: the lamp envelope is sealed to a stem tube of which the end situated within the lamp envelope is sealed in a gas~tight manner with a pinch around wires which have an matched coe~icient of expan-sion and serve as current lead-through conductors. To the respective ends of these current lead-through wires, inner and outer current conductors are welded. In this known lamp, contrary to current GLS lamps, the fuse consists cf a central portion of one of said current lead-through wires, which central portion is si-tuated in a cavity within the pinch and has a smaller diameter than the other current lead-through wire. As in said kno~n lamp -the fuse is constitu-ted by the cen-tral portion of the wire, that is with its ends, adjacent to the central portion, embedded in the pinch in a vacuum-tight manner, said cavity within the pinch is hermetically separated from the cavity of the lamp envelope and from -the ambient atmosphere.
In this connection it is to be noted that we have established experimentally, that in halogen incan-descent lamps the current lead-through conductor (-the metal foil) incorpora-t0d :in a correspond:Lng manner wi-th its central portion free from the glass in the cavity in the pinch, does not ~orm a reliable f`use, Consequently, instead of an incentive to arrive at the lamp ln accor-dance with the invention~ the known lamp cons-tituted an impedance thereto. Moreover the lamp of the invention has .
Pl~ 9719 7 11.11.1980 the advantage over said known GLS lamp that noother, thinner parts need to be used than are commonly used in lamps without a fuse~ The presence of the fuse further-more constitutes no inconvenience in the manufac-ture of the lamp and the fuse causes no or hardly any additional power consumption during normal opera-tion of the lamp.
The lamps in accordance with the invention are particularly suitable for design as mains voltage lamps.
They may be used inter alia as thea-ter lamps~ film lamps, studio lamps and photo larnps.
Embodiments o~ halogen incandescent lamps accor-ding to the invention are shown in the accompanying dra-wingO In the drawing:
Fig. 1 is an elevation of a first embodiment of a lamp;
Fig~ 2 is an axial sectional view of a modified embodiment of -the lamp shown in Fig. 1 rotated 90 about its axis;
Fig. 3 is an elevation of a further embodiment 0~ a lamP;
Fig. 4 is an elevation of a mono-pinch lamp;
Fig. 5a is an elevation of an embodiment of a two pinch lamp;
Fig. 5b is a diagrammatic representation of a component of Fig. 5a, and Fig. 6 is an elevation of a further embodiment of a two-pinc~ lamp.
In Fig. 1 a quartz glass lamp envelope 1 is sealed by means of pinches 2. In the cavi-ty 3 of -the envelope, which is filled with inert gas and hydrobromide, a tungsten filament 4 is accommodated which is centred by supporting mambers 5. Incorporated in each o~ -the pinches
PHN ~719 1 11.11.lg8o "~Ialogen incandescent lamp".
The invention relates to a halogen incandescent lamp having a quartz glass lamp envelope, whose cavity is filled with a halogen-containing inert gas and in which a tungsten filament is accommodated~ which lamp envelope is sealed by means of a pinch in which at least one rnetal foil is embedded to whose respective ends an internal current conductor to the filament and an external curren-t conductor are welded, which lamp has a fuse accommodated in an en-closed space bounded by the pinch. Such a lamp is disclo-1~ sed in the United States Patent Specifica-tion 3,264,516.
In by far most of the cases, halogen incandescen-t lamps have a gas filling with a pressure of approxima-tely 1 bar or more which during operation increases by a factor of 4 or 5. When at the end of the life of such a lamp the filament or an internal current conductor fuses, a dischar-ge arc is formed in the lamp which produces a high current strength and can penetrate into the pinch. The rapid evapo-ration of the metal parts incorporated in the pinch then causes cracking of the pinch, the lamp exploding as a result of the high gas pressure. This process occurs so rapidly that the use of an external fuse does not prevent explosion of the lamp with certainty. In addition many luminaires do not have such a fuse.
In the lamp which is disclosed in the above-mentioned Uni-ted States Patent Specification, a hollow space adjoins the end of the pinch remote from the filamen-t and is closed by a second pinch~ ~ thin conductor extends in said space and is connected at orle end vla a -thicker conductor to the foil in the pinch of the lamp and at its other end is connected to a contac-t cap situated outside the lamp envelope. This thin conductor serves as a fuse.
The cons-truc-tion of the known lamp suffers from .~
P~IN 9719 2 11.11.1980 a number of disadvantages. The manufac-ture of the lamp is considerably more laborious than -that of lamps without a fuse. More componen-ts are used therein than in lamps without a fuse. The fuse wire should be very thin because otherwise a vacuum-tight second pinch canno-t be made around the wire due to the large differences in coeffi-cients of thermal expansion between quartz glass and me-tal.
However, a vacuum tight seal is necessary so as to prevent corrosion of the wire. The small diameter of the wire - a vacuum-tight seal is possible on wires up to approximately 1~0tum diameter - causes loss of energy. Wi-th an extra enclosed space for the fuse of 20 mm length and an e~tra pinch at the relevant end of the lamp envelope the con-struction produces a considerably longer lamp. Furthermoremeasures should be taken to prevent corrosion of the fuse wire in so far as it projects beyond the extra pinch.
It is -the object of -the inven-tion to provide a lamp having a built-in fuse in which said disadvantages are at least mitigated, more especially a lamp which, in spite of the presence of a built-in fuse, need no-t comprise more or different components than a comparable lamp without a fuse.
~ ccording to the invention this object is achieved in a lamp of the kind described in the opening paragraph in that the enclosed space is provided within the pinch such that a part of the internal current conduc-tor extends through the space so as to be cicumferentially free from the surrounding quartz glass of the pinch9 which part constitutes the fuse.
Quartz glass is -to be understood -to mean herein glass having a silicon dloxide content of a-t least ~/0 by weight.
If as a result of the fusing of the filament or an internal current conductor, a discharge arc is formed in the cavi-ty of the lamp envelope in which the filament is accommodated. As a result, the current through the lamp, and hence through the internal current conductor, increases PHN 9719 3 11. 11 . 1980 considerably. Since at least one internal current conductor is circumferentially free from the glass over a part of its length in the enclosed space within the pinch~
the heavy current through said in-ternal current conduc-tor 5 results in a la~ger rise in temperature than if said current conductor were embedded in the glass of t~e pinch and would hence be cooled by said glass. As a result of this the conductor fuses very rapidly. However, it has been found that no discharge arc is formed in the enclosed space with-lO in the pinch, possibly because the temperature in saidspace, which communicates with the cavity of the lamp enve-lope only via a narrow capillary duct which is inevitably formed during making the pinch, is much lower than in the cavity of the lamp envelope in which the filament is accommo l5 dated.
The weld o~ the internal current conduc-tor to the metal foil, which generally consists of tungsten or molyb-denum9 may be present beyond the enclosed space which is provided within the pinch. In an embodiment of the lamp in 20 accordance with the invention said weld, however, may be present in the enclosed space pro~idsd within the pinch.
Because it is di~ficult to weld tungsten wire to a tungsten or molybdenum foil, it is likely that, in rnanufacturing lamps, besides many good welds also a few bad welds are 25 obtained. As a result of the high contact resistance of bad welds, high temperatures may arise which lead to crack-ing of the pinch. In the last-mentioned ernbodiment of the lamp in accordance wi-th the invention, this danger is also avaided.
The lamp in accordance with the invention no-t only has the advantage that no additional par-ts are necessa ry as compared with non-safeguarded lamps and that the fuse is excluded from the ambient air by the vacuum-tlght seal of the lamp itself so tha-t air cannot cause corros:ion~ lt 35 also has the advan-tage that a varie-ty of constructions of internal current conductors wh:ich are in common use may be used. For example, the straight limb of a single coiled "~
PHN 9719 4 11.11.1980 cO
(sc.) filament or the single ~ limb of a coiled coil (c.c.) filament may be used as an internal current conduc-tor. On the other hand it is possible to construct the internal current conduc-tor as a straight wire wound helical_ ly at one or both ends or as an entirely helically wound wire which is screwed in or around one end o~ the ~ila-ment. In a coiled coil filament, fur-thermore, a single coiled limb may be slid over a straight wire and be attach-ed thereto by pinching or welding. In cases in which an internal curre.nt conductor is helically wound in the region where it is welded to the metal foil9 a straight piece of wire is of-ten inserted into the helix of the internal current conductor so as to facilitate the making of a weld with the metal foil. Such a piece of wire may be omitted in a construction in which a second layer of turns is provided on the helically wound internal current conduc-tor in the region where the weld is to be made. The second layer of turns may be formed from the same wire as the first layer. This may be the case both when the internal current conductor is the limb of the ~ilament, and also when the internal current conduc-tor is a separate compo-nent. An short even-t, when making the internal curren-t conduc-tor the winding wire, after having made -the first layer of -the -turns, is wound with opposite winding sense over the firs-t layer, after which, if desired9 a third layer of turns can be provided with the original winding sense. The advantage of this latter embodiment is that several intercoupled filaments can be obtained in a con-tinuous operation, ~hich f:ilaments are -then separated.
In lamps having a long computed li~e the danger exists that the par-t of the internal co:nductor extending in the cavity o~ the :Larnp enve:Lope is attaclced by -tho halogen of the gas f:illing. This attack may res-ult in s~-Lch a local reductl.on in diameter of the i.nternal curren-t con_ d-uc-tor tha-t the lamp e~tinguishes prematurely when said current conduc-tor fuses.
Lamps in accordance with the invention presen-t ]`~
P~IN 9719 5 11.11.19~0 the possibility o~ readily constructing the internal current conductor whilst nevertheless -taking into accound re~uirements which, dependen-t on the type o~ the lamp, are imposed on said current conductor ~or the sa-tis~ac-tory 5 operation of the lamp~ for example a minimum wire diame-ter for the said curren-t conductor. It has been found tha-t the wire diameter of the internal current conductor may be larger than the wire diameter of the filament so -that the number of hours in operation in which the internal conductor 10 is attacked to such an extent as to break or to fuse can be matched to the computed life of the ~ilament. For example with internal conductors having a 20% larger wire diameter than the wire diameter o~ the filament, a reliable fuse in lamps in accordance with the invention was nevertheless 15 obtained.
Since in the lamp in accordance with the invention the use of thinner than normal (i.e~ fusible) conductors, and the use of additional components can be avoided, mecha-nically strong lamps can be manufactured in a simple manner 20 and nevertheless have a built-in fusel The fuse construction of lamps in accordance with the invention makes it possible to construct the lamp as a mono-inch or as a two~inch lamp.
In mono-pinch lamps one or both internal current conductors to the filament may extend through the enclosed space provi-25ded within the pinch. In two~nch lamps~ both internalcurrent conductoxs ma-~A extend -through an enclosed space provided within the respective pinches.
The presence of an enclosed space within the pinch through which the internal current conductor extends 30so as to be circwnferentiall~ free from the glass o~ the pinch, is revea]ed by the presence of a local boss on the pinch surface. This is obtained by providing the pinching blocks with which the pinch is manu~actured with a recess.
The boss, and hence -the resulting enclosed space, preferably 35ex-tends substantially over the whole width o:~ the pinch so that the enclosed space is as large as possible witho-ut this involving any or an~ noteworthy increase o~` the overall length o~ the lamp.
PHN 9719 6 11.11.1980 It is to be noted that in lamps in accordance with the invention, as is always the case in lamps having a metal foil incorporated in the pinch as a current lead-through conductor, the vacuum-tight seal of the lamp envelope is realised in that zone of the pinch which is situated between the welds on the metal foil.
It is furthermore to be noted -that a lamp for general lighting purposes (GLS lamp) is described in British Patent Specification ~60.976, (published already in 1937) which lamp also has a fuse. The lamp has a con-struction which, e~cept for thefuse, is similar -to that of the curre~t GLS lamp: the lamp envelope is sealed to a stem tube of which the end situated within the lamp envelope is sealed in a gas~tight manner with a pinch around wires which have an matched coe~icient of expan-sion and serve as current lead-through conductors. To the respective ends of these current lead-through wires, inner and outer current conductors are welded. In this known lamp, contrary to current GLS lamps, the fuse consists cf a central portion of one of said current lead-through wires, which central portion is si-tuated in a cavity within the pinch and has a smaller diameter than the other current lead-through wire. As in said kno~n lamp -the fuse is constitu-ted by the cen-tral portion of the wire, that is with its ends, adjacent to the central portion, embedded in the pinch in a vacuum-tight manner, said cavity within the pinch is hermetically separated from the cavity of the lamp envelope and from -the ambient atmosphere.
In this connection it is to be noted that we have established experimentally, that in halogen incan-descent lamps the current lead-through conductor (-the metal foil) incorpora-t0d :in a correspond:Lng manner wi-th its central portion free from the glass in the cavity in the pinch, does not ~orm a reliable f`use, Consequently, instead of an incentive to arrive at the lamp ln accor-dance with the invention~ the known lamp cons-tituted an impedance thereto. Moreover the lamp of the invention has .
Pl~ 9719 7 11.11.1980 the advantage over said known GLS lamp that noother, thinner parts need to be used than are commonly used in lamps without a fuse~ The presence of the fuse further-more constitutes no inconvenience in the manufac-ture of the lamp and the fuse causes no or hardly any additional power consumption during normal opera-tion of the lamp.
The lamps in accordance with the invention are particularly suitable for design as mains voltage lamps.
They may be used inter alia as thea-ter lamps~ film lamps, studio lamps and photo larnps.
Embodiments o~ halogen incandescent lamps accor-ding to the invention are shown in the accompanying dra-wingO In the drawing:
Fig. 1 is an elevation of a first embodiment of a lamp;
Fig~ 2 is an axial sectional view of a modified embodiment of -the lamp shown in Fig. 1 rotated 90 about its axis;
Fig. 3 is an elevation of a further embodiment 0~ a lamP;
Fig. 4 is an elevation of a mono-pinch lamp;
Fig. 5a is an elevation of an embodiment of a two pinch lamp;
Fig. 5b is a diagrammatic representation of a component of Fig. 5a, and Fig. 6 is an elevation of a further embodiment of a two-pinc~ lamp.
In Fig. 1 a quartz glass lamp envelope 1 is sealed by means of pinches 2. In the cavi-ty 3 of -the envelope, which is filled with inert gas and hydrobromide, a tungsten filament 4 is accommodated which is centred by supporting mambers 5. Incorporated in each o~ -the pinches
2 is a molybdenum foil 6 as a c~rrent lead-through conduc-tor to which a limb 7 of filament 4 is secured by a weld ~.
External current conductors 9 are securecl to the foils 6 by means of respective welds 10. A space 11 is provided within the pinohes 2, in which space a part 12 o~ the ~ ~;S~ 3 PHN 9719 8 11.11.1980 respective internal current conductors 7 is circumferen-tially free from the glass of the respective pinch 2. The pinch 2 is vacuum-tight over the zone 13 centrally of the ~oil 6. The space 11 comm~micates with the cavity 3 of the lamp envelope 1 through a capillary duc-t aro~md the interna~
current conductor 7, which duct has been formed after pinching in -that the (tungsten)conductor 7 has a larger coefficient of expansion than the quartz glass of the lamp envelope~
In Fig. 2 in which the same reference numerals are used for the same- components as in Fig. 1, pinch 2 is identical to the pinches 2 in Fig. 1 but pinch 22 is a conventional pinch in which the internal current conductor 27~ in so far as it extends within the pinch~ is embedded in the glass of -the pinch. 14 deno-tes a boss on the pinch surface of pinch 2 which surrounds the presence of the cavity 11 in the pinch 2 is expressed.
In Fig. 3 the lamp envelope 31 has a pinch 32.
A filament 34 centred by a supporting member 35 is accom-20 modated in the cavity 33. A metal foil 36 to which a wire37 wound helically for the greater part is welded at 38 is embedded in the pinch 32. The wire 37 is screwed in the helical filament 34 as an internal current conduc-tor. An external current conductor 39 is welded to the foil 36 at 25 4- A cavity 41, in which -the weld 38 between the foil 36 and the internal current conduc-tor 37 is situated, is formed within the pinch 32. A part 42 of said internal conductor 37 extends in said cavity 41 so as to be circum-ferentiàlly free from the glass.
The lamp envelope 51 in Fig. 4 has only one pinch 52 in which me-tal foils 56 are embedded to which external current conductors 59 are secured by means of respective welds 60. Internal current conductors 57 in ono end have a tungsten wire 63 inserted therein on which a weld has been 35 made -to a respective metal foil 56. The part 62 of one of the current conduc-tors 57 is circ-umferen-tia:Lly free from the surrounding glass in a cavity 61 formed in the pinch 52.
The internal current conduc-tors 57 are each screwed in-to ~6~
PHN 9719 9 11. 11. 1980 the filament 54 which is supported by means o~ a hooked support.
In Fig. ~a a ~oiled coil filament 74 is accommo-dated in the cavity 73 of the lamp envelope 71, of which filament the limb 77 is an internal current conductor. The limb 77 consists of three layers of turns of the wire from which the filament 74 is wound. The limb 77 was obtained (see Fig. 5~) by providing on a single coiled part 77a turns of opposite winding sense as a second layer 77b and lO providing thereon a third layer of turns 77c having the original winding sense.
A part 82 of the internal current conductor 77 is incorporated in a space 81 formed within -the pinch 73, in which space it is circumferentially free from the glass 15 and is welded to a molybdenum foil 76 to which an external current conductor 79 has also been welded.
In Fig. 6 corresponding reference numerals denote the same components as in Fig. 5. In the single coiled lim~ 83 of the filament 74 a wire 84 is inserted which is 20 welded to the foil 76. The wire extends substantially up to the filament 74 and is welded to the limb 83 in a place situated in -the space 81. The wire 84 and the limb 83 to-gether constitute an internal current conductor which in the space 81 is circumferentially free from the glass of the 25 pinch 72.
Example 1.
A lamp which cons~ed 500 W a-t 220-230 V was constructed with both ends as shown in Fig. 6 and had a coiled coi1 filament wound from -tungsten wire of 121/um 30 diameter. In each of the single coiled ~rnbs 83 of the fila-ment (internal diameter of the turns of the limbs 190/um) a tungsten wire (8l~) of 1~0/um has been insert~d and secu-red therein by plea-ting a few of the turns. The length, in the axial direction O:r the lamp, o~ the spaces 81 formed 35 in each of the pinches was 6 mm. The largest heigrht of sa:id spaces (measured perpendic-ularly to the pinch) was 2.5 mm.
The welds of the tungsten wires ~ to -the foils 76 were ~SI
PH~ 9719 10 11.11.1980 si-tuated in -the spaces 81 recessed wi-thin the pinch. The lamp was filled with 99.7% by volume of Ar and 0~3% by volume of CH3Br to a pressure of 2.5 x 105 Pa and further comprised 5 mg of iodine.
2. A lamp which consumed 300 W at 220-230 V was constructed at each end as shown in Fig. 5a. The coiled coil filament was wound from tungsten wire of 82/-um diame-ter (inside diameter of the primary tuns 1l1/um). The win-ding wire had been wound backwards and forwards on the l single coiLed limbs (77) of the filament (Fig. 5b), so that three la~ers of turns were present. The limbs 77 were each welded to a molybdenum foil as an internal current conductor. In each of the pinches 72 a cavi-ty 81 had been formed having a length of 4 mm and a height of 2.5 mm~ in which the weld to the molybdenum foil was also present. The lamp was filled with 99. 8% by volume of Ar and 0.2% by volume of CH2Br2 to a pressure of 2.5 x 105 Pa and further comprised 5 mg of iodine.
Both lamps were des-tined for use as a flood-light lamp-A few tens of each of these types of :Lamps weretested for the effec-tiveness of the incorporated fuse.
During -the test, the filament was fused by means of a laser during operation of the lamps. The fuses became opera-tive and switched off the lamps substantially instantane-ously~
A few lamps of both types were manufactured with a filament which was short-circuited for 1/4 part of its length by means of a mandrel inserted therein. A voltage of 280 ~ was applied -to the lamps. The incorporated fuses fused substantially instantaneously within a few millise-conds.
External current conductors 9 are securecl to the foils 6 by means of respective welds 10. A space 11 is provided within the pinohes 2, in which space a part 12 o~ the ~ ~;S~ 3 PHN 9719 8 11.11.1980 respective internal current conductors 7 is circumferen-tially free from the glass of the respective pinch 2. The pinch 2 is vacuum-tight over the zone 13 centrally of the ~oil 6. The space 11 comm~micates with the cavity 3 of the lamp envelope 1 through a capillary duc-t aro~md the interna~
current conductor 7, which duct has been formed after pinching in -that the (tungsten)conductor 7 has a larger coefficient of expansion than the quartz glass of the lamp envelope~
In Fig. 2 in which the same reference numerals are used for the same- components as in Fig. 1, pinch 2 is identical to the pinches 2 in Fig. 1 but pinch 22 is a conventional pinch in which the internal current conductor 27~ in so far as it extends within the pinch~ is embedded in the glass of -the pinch. 14 deno-tes a boss on the pinch surface of pinch 2 which surrounds the presence of the cavity 11 in the pinch 2 is expressed.
In Fig. 3 the lamp envelope 31 has a pinch 32.
A filament 34 centred by a supporting member 35 is accom-20 modated in the cavity 33. A metal foil 36 to which a wire37 wound helically for the greater part is welded at 38 is embedded in the pinch 32. The wire 37 is screwed in the helical filament 34 as an internal current conduc-tor. An external current conductor 39 is welded to the foil 36 at 25 4- A cavity 41, in which -the weld 38 between the foil 36 and the internal current conduc-tor 37 is situated, is formed within the pinch 32. A part 42 of said internal conductor 37 extends in said cavity 41 so as to be circum-ferentiàlly free from the glass.
The lamp envelope 51 in Fig. 4 has only one pinch 52 in which me-tal foils 56 are embedded to which external current conductors 59 are secured by means of respective welds 60. Internal current conductors 57 in ono end have a tungsten wire 63 inserted therein on which a weld has been 35 made -to a respective metal foil 56. The part 62 of one of the current conduc-tors 57 is circ-umferen-tia:Lly free from the surrounding glass in a cavity 61 formed in the pinch 52.
The internal current conduc-tors 57 are each screwed in-to ~6~
PHN 9719 9 11. 11. 1980 the filament 54 which is supported by means o~ a hooked support.
In Fig. ~a a ~oiled coil filament 74 is accommo-dated in the cavity 73 of the lamp envelope 71, of which filament the limb 77 is an internal current conductor. The limb 77 consists of three layers of turns of the wire from which the filament 74 is wound. The limb 77 was obtained (see Fig. 5~) by providing on a single coiled part 77a turns of opposite winding sense as a second layer 77b and lO providing thereon a third layer of turns 77c having the original winding sense.
A part 82 of the internal current conductor 77 is incorporated in a space 81 formed within -the pinch 73, in which space it is circumferentially free from the glass 15 and is welded to a molybdenum foil 76 to which an external current conductor 79 has also been welded.
In Fig. 6 corresponding reference numerals denote the same components as in Fig. 5. In the single coiled lim~ 83 of the filament 74 a wire 84 is inserted which is 20 welded to the foil 76. The wire extends substantially up to the filament 74 and is welded to the limb 83 in a place situated in -the space 81. The wire 84 and the limb 83 to-gether constitute an internal current conductor which in the space 81 is circumferentially free from the glass of the 25 pinch 72.
Example 1.
A lamp which cons~ed 500 W a-t 220-230 V was constructed with both ends as shown in Fig. 6 and had a coiled coi1 filament wound from -tungsten wire of 121/um 30 diameter. In each of the single coiled ~rnbs 83 of the fila-ment (internal diameter of the turns of the limbs 190/um) a tungsten wire (8l~) of 1~0/um has been insert~d and secu-red therein by plea-ting a few of the turns. The length, in the axial direction O:r the lamp, o~ the spaces 81 formed 35 in each of the pinches was 6 mm. The largest heigrht of sa:id spaces (measured perpendic-ularly to the pinch) was 2.5 mm.
The welds of the tungsten wires ~ to -the foils 76 were ~SI
PH~ 9719 10 11.11.1980 si-tuated in -the spaces 81 recessed wi-thin the pinch. The lamp was filled with 99.7% by volume of Ar and 0~3% by volume of CH3Br to a pressure of 2.5 x 105 Pa and further comprised 5 mg of iodine.
2. A lamp which consumed 300 W at 220-230 V was constructed at each end as shown in Fig. 5a. The coiled coil filament was wound from tungsten wire of 82/-um diame-ter (inside diameter of the primary tuns 1l1/um). The win-ding wire had been wound backwards and forwards on the l single coiLed limbs (77) of the filament (Fig. 5b), so that three la~ers of turns were present. The limbs 77 were each welded to a molybdenum foil as an internal current conductor. In each of the pinches 72 a cavi-ty 81 had been formed having a length of 4 mm and a height of 2.5 mm~ in which the weld to the molybdenum foil was also present. The lamp was filled with 99. 8% by volume of Ar and 0.2% by volume of CH2Br2 to a pressure of 2.5 x 105 Pa and further comprised 5 mg of iodine.
Both lamps were des-tined for use as a flood-light lamp-A few tens of each of these types of :Lamps weretested for the effec-tiveness of the incorporated fuse.
During -the test, the filament was fused by means of a laser during operation of the lamps. The fuses became opera-tive and switched off the lamps substantially instantane-ously~
A few lamps of both types were manufactured with a filament which was short-circuited for 1/4 part of its length by means of a mandrel inserted therein. A voltage of 280 ~ was applied -to the lamps. The incorporated fuses fused substantially instantaneously within a few millise-conds.
Claims (3)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A halogen incandescent lamp having a quartz glass lamp envelope whose cavity is filled with a halogen containing inert gas and in which a tungsten filament is accommodated, which lamp envelope is sealed by means of a pinch in which at least one metal foil is embedded to whose respective ends an internal current conductor to the fila-ment and an external current conductor are welded, which lamp has a else accommodated in a space bounded by thepinch, characterized in that the space is formed within the pinch such that a part of the said internal current conductor extends through the space so as to be circumferentially free from the surrounding quartz glass of the pinch, which part constitutes the fuse.
2. A halogen incandescent lamp as claimed in Claim 1, characterized in that the weld of the internal current conductor to the metal foil is also situated in the said space.
3. A halogen incandescent lamp as claimed in Claim 1 or 2, characterized in that both internal current conduc-tors extend through said space so as to be circumferentially free from the quartz glass of the pinch.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NLAANVRAGE8001670,A NL179957C (en) | 1980-03-21 | 1980-03-21 | HALOGEN LIGHT. |
| NL8001670 | 1980-03-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1165800A true CA1165800A (en) | 1984-04-17 |
Family
ID=19835037
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000373372A Expired CA1165800A (en) | 1980-03-21 | 1981-03-19 | Halogen incandescent lamp |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS56145653A (en) |
| BE (1) | BE888028A (en) |
| BR (1) | BR8101590A (en) |
| CA (1) | CA1165800A (en) |
| DE (1) | DE3110395A1 (en) |
| FR (1) | FR2478877A1 (en) |
| GB (1) | GB2072416B (en) |
| HU (1) | HU186388B (en) |
| IT (1) | IT1168112B (en) |
| NL (1) | NL179957C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4849669A (en) * | 1986-11-28 | 1989-07-18 | U.S. Philips Corporation | Electric incandescent lamp for operation at line voltage |
| AT398864B (en) * | 1990-03-15 | 1995-02-27 | Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh | HALOGEN BULB |
| EP0802561B1 (en) * | 1996-04-19 | 2000-07-19 | Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH | Halogen lamp |
| US6653782B2 (en) * | 2001-12-27 | 2003-11-25 | Koninklijke Philips Electronics N.V. | Fuse and safety switch for halogen incandescent lamps |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE646240C (en) * | 1935-08-08 | 1937-06-14 | Patra Patent Treuhand | Electric lamp with built-in fuse |
| US3264516A (en) * | 1961-10-31 | 1966-08-02 | Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh | Tubular incandescent lamp |
| US3864598A (en) * | 1973-08-01 | 1975-02-04 | Gen Electric | Incandescent lamp with internal fuse |
| FR2274292A1 (en) * | 1974-06-12 | 1976-01-09 | Roussel Uclaf | NEW SPIROHETEROCYCLANIC COMPOUNDS, THEIR PREPARATION PROCESS AND THEIR APPLICATION AS A MEDICINAL PRODUCT |
-
1980
- 1980-03-21 NL NLAANVRAGE8001670,A patent/NL179957C/en not_active IP Right Cessation
-
1981
- 1981-03-18 GB GB8108451A patent/GB2072416B/en not_active Expired
- 1981-03-18 HU HU81699A patent/HU186388B/en unknown
- 1981-03-18 IT IT20408/81A patent/IT1168112B/en active
- 1981-03-18 BR BR8101590A patent/BR8101590A/en unknown
- 1981-03-18 JP JP3804181A patent/JPS56145653A/en active Pending
- 1981-03-18 DE DE19813110395 patent/DE3110395A1/en not_active Ceased
- 1981-03-19 BE BE0/204190A patent/BE888028A/en not_active IP Right Cessation
- 1981-03-19 CA CA000373372A patent/CA1165800A/en not_active Expired
- 1981-03-20 FR FR8105635A patent/FR2478877A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| IT8120408A0 (en) | 1981-03-18 |
| FR2478877B1 (en) | 1984-02-10 |
| NL179957B (en) | 1986-07-01 |
| IT1168112B (en) | 1987-05-20 |
| NL8001670A (en) | 1981-10-16 |
| BR8101590A (en) | 1981-09-22 |
| HU186388B (en) | 1985-07-29 |
| IT8120408A1 (en) | 1982-09-18 |
| DE3110395A1 (en) | 1982-04-15 |
| BE888028A (en) | 1981-09-21 |
| GB2072416A (en) | 1981-09-30 |
| FR2478877A1 (en) | 1981-09-25 |
| GB2072416B (en) | 1983-05-25 |
| JPS56145653A (en) | 1981-11-12 |
| NL179957C (en) | 1986-12-01 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |