CA1155901A - Electric lamp having a partly mirrored lamp envelope - Google Patents
Electric lamp having a partly mirrored lamp envelopeInfo
- Publication number
- CA1155901A CA1155901A CA000355320A CA355320A CA1155901A CA 1155901 A CA1155901 A CA 1155901A CA 000355320 A CA000355320 A CA 000355320A CA 355320 A CA355320 A CA 355320A CA 1155901 A CA1155901 A CA 1155901A
- Authority
- CA
- Canada
- Prior art keywords
- lamp
- lamps
- envelope
- coloured
- lamp envelope
- 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
- H01K1/28—Envelopes; Vessels
- H01K1/32—Envelopes; Vessels provided with coatings on the walls; Vessels or coatings thereon characterised by the material thereof
- H01K1/325—Reflecting coating
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01K—ELECTRIC INCANDESCENT LAMPS
- H01K1/00—Details
- H01K1/28—Envelopes; Vessels
Landscapes
- Vessels And Coating Films For Discharge Lamps (AREA)
- Optical Elements Other Than Lenses (AREA)
Abstract
PHN. 9536 ABSTRACT: 7 Electric lamps having a lamp envelope which is partly mirrored with aluminium, chromium or silver have a cold look, which is not the case with lamps having a gold or imitation gold mirror. However, gold has a poor adhesion to glass, while imitation gold mirrors have to be built up from several pairs of copper and aluminium layers, which involves a high cost price. In lamps accord-ing to the invention the lamp envelope is transparent smoke-coloured at least at the area of the silver coloured mirror, by means of a lacquer layer, an enamel layer, or the use of smoke-coloured glass for the lamp envelope.
Description
3Ll$590~.
PHN. 9S36 The invention re:lates to an electric lamp having a sealed vacuum tight glass lamp envelope through the wall of which current supply conductors to an electric element accommodated in the lamp envelope pass to the exterior where they are attached to a lamp cap connected to the lamp envelope, the wall of said lamp envelope being pro-vided with a metal reflecting layer over a part of its inner surface.
Such lamps are yenerally known, inter alia from United States Patent Specification 2,070,700 - Welsbach Street Lighting Company of America:and issued on February 16, 1937 and are commercially available.
Usually the lamps are incandescent-lamps in which either the part of the lamp envelope opposite to the lamp cap or a 15: part of the lamp en~elope.situated near the lamp cap is mirrored. In the former case we have bowl-mirrored lamps :
in which a spherical or substantially spherical part of the lamp envelope is mirrored.and which are used in a reflector to obtain a narrow light beam; in the latter case 2Q. we have mirrored lamps whi~h produce a comparatively narrow light.beam without.further optical:auxiliary means. Among :
:these latter lamps:are~rirlg mirror lamps ha~ing a blown ~ lamp envelope the mirrored part:of which is usually curved : para~oloidally, and lamps ~rom pressed glass the lamp :25 envelope of which consists of a paraboloidal cup which is closed with a co~er glass.
For mirroring.a part of a lamp envelope,.aluminium or silver is:frequently used dué.to the high coefficient of reflection of said metals~, or chromium is used. Since much wood and leather is~used in t~e present-day interiors, larnps having silver coloured,~aluminium~ silyer, or chromium, : mirrors.are out of keepin~ in such interiors. Bowl mirrored lamps are nearly:always mounted so as to~be visible, :
whi]e ring mirror lamps and pressed glass lamps 1 1559~.~
PHN 9536 2 20.3.1980 are frequently used in luminaires only surrounding the lamp cap of the lamps.
In order -to remove the optically cold impression of mirrored lamps, such lamps are therefore provided with a gold coloured mirror. ~owever, the disadvantage of the use of gold is a high cost price and a poor adhesion of said metal to glass, so that after a small number of hours in operation a crackled effect is already obtained which adversely influences the concentrating effect of the mirror.
Other commercially~available lamps having a gold coloured mirror have been manufactured by vapour-deposit-ing alternately copper and cilver~or aluminium. ~or the benefit of a good adhesion sai.d materials must be vapour-deposited in very thin layers whi~ch are each not comple-tely dense, that is they do not have a uniform optical density throughout their surface so that several layer pairs must be provided so as -to obtain the desired effect.
This makes the manufacture of the lamps time-consuming 0 and experlsive, It is the object of the invention to provide mirror lamps in which on the one hand the disadvantage o~ silver-coloured mirrors is avoided and on the other hand the disadvantages of the use of gold or imita-tion 25~ gold~mirrors are avoided.
In elec-t~ric lamps of the kind described in the opening para~raph this object is achieved in that the metal layer is~silver coloured and that at least that part o~ the lamp envelope which is provided with the me-tal layer has a transparent smoke-colour.
In an embodiment of a lamp in accordance with the invention this has been reallsed by manufacturing the lamp envelope entirely or par-tly from smoke-coloured glass.
In another embodiment, however, the inner sur-face, the outer surface or -the inner and outer surface of the lamp envelope has a transparent, smoke-coloured layer. When only the inner surface has such a layer, the :. : .
1 ~55~Q~
PHN 9536 3 20.3.1980 mirror layer, of course, is present on the colour layer.
A smoke-coloured layer on the outer surface of the lamp envelope has the advantage that only one type of lamp need be manufactured of which a number may be provided with a coloured layer, as required, at the end of the production process~ whereas the remaining lamps can be sold as silver-ed lamps.
The colour layer may consist of a smoke-coloured enamel or of a smoke-coloured lacquer. As a lacquer are to be considered in particular silicone lacquers due to their stability at higher temperatures. They can easily ;~ be pro~ided by spraylng or dipping while diluted with solvents or be provided in an electrostatic coating process.
In bowl mirrored lamps in which the part of the lamp envelope situated opposite to the lamp cap is mirrored, it will nearly always suffice to colour the mirrored wall portlon~ for~example~by providing a colour layer on the outside of the lamp envelope. When placed in a luminaire,~
; bowl mirrored lamps hardly ever give the occasion of ob-~serving the insi~de~of'the mirror. Such a lamp~glves the impression of having a~gold mirror. Lamps having~a gold mirror give~light~o~'~a warmer~t~inge than Iamps having a silver-coloured~mirror. If~lt~is desired for lamps~accord~
;ing to the invention also to emit light of a warmer tinge~
~the wlndow of~th~è~;lamp~envelope;through which~the~ ght ;
emanates is also provided with a~`smoke-colouréd;layer.
5~ ~ In lamps in~whi'ch~a part of t~he lamp envelope ;
which is situated closer to the lamp cap is mirrored, it ~ ' wlll also suffioe to oolour the~mlrrored~wall~part.~ow~
ever, these lamps may also be~us~ed~so that the inside of the metal mirror can also be~observed.~Therefore, in this ~ ;
type of lamps the window of the lamp envelope~is prefe~
rably also coloured so as to give them a unive~rsal appli-cation as imitation gold mirror lamps.
In order to rnake a silve~r-coloured, silver, aluminium or chromium, mirror gold coloured, a slightly coloured coating layer or a slightlv coloured glass is sufficient. A smaLl series of tests will enable the exp~rt :
' .' ~ .. .
:~' 1 ~5590~
PHN 9536 4 20.3.1980 to determine the desired colour and colour intensity.
The measure used in lamps according to the invention is particularly suitable for incandescent lamps in which the electric element is a filament but is also suitable for discharge lamps in which -the electric element is a pair of electrodes in an ionisable gas, usually en-veloped by a discharge vessel.
Embodiments of lamps according to the invention are shown in the drawing. In the drawing lD Fig. 1 is an elevation, partly broken away, of a bowl mirrored incandescent lamps;
Fig. 2 is an elevation partly broken away of a pressed glass discharge lamp;
Fig. 3 is an elevation partly broken away of a .
lS ring mirror incandescent lamp.
~ In Fig. 1, the lamp envelope 1 is provided with ~ ;
a silver layer 4 over its part 2 situated opposite to the lamp cap 3. Part 2 is coated on its outside with a trans-parent smoke-coloured~iron oxide-eontaining enamel layer 5.
A filament 6 is accommodated~between current supply con~
duc~tors 7 and 8 which are connected to the lamp cap 3.
Between its ends the fil~ament 6 is supported by wires 9.
The lamp in Flg.~ 2 has a bipartite lamp envelope 20, 21 of press~ed glass.~The paraboloidal part 20 is~
25 ~covered with an alumlnlum~layer 22 and is mada of~smoke~
coloured glassO The cover~glass 21 is of colourless pressed glass. Connected to the lamp envelope lS~ a lamp cap 23 from which current suppl~ conductors 24 and 25 e~tend to a high pressure sodium vapour discharge vessel 26.~
The lamp envelope 30 in~Fig. 3 has a paraboloid-ally eurved lamp envelope part 31 which is eovered with an aluminium layer 32. Lamp envelope part 31, like window 33 and the neck-shaped part 34 of the lamp envelope, to which a lamp cap 35 is secured, is co~ered with a smoke~coloured lacquer layer 36. A filament which is hidden from view by the mirror 32 is supported by wires 37 a~d provided with current by current supply conductors 38 which are connected to the lamp cap 350 : . :
PHN 9536 5 20.3.1980 EXAMPLE.
Larnps as shown in ~ig. 3 having a larnp envelope with a largest diameter of 63 mm had an aluminium mirror vapour-deposited in a vacuum. The lamp envelope was dipped in a bath of 68 g of s:ilicone resin
PHN. 9S36 The invention re:lates to an electric lamp having a sealed vacuum tight glass lamp envelope through the wall of which current supply conductors to an electric element accommodated in the lamp envelope pass to the exterior where they are attached to a lamp cap connected to the lamp envelope, the wall of said lamp envelope being pro-vided with a metal reflecting layer over a part of its inner surface.
Such lamps are yenerally known, inter alia from United States Patent Specification 2,070,700 - Welsbach Street Lighting Company of America:and issued on February 16, 1937 and are commercially available.
Usually the lamps are incandescent-lamps in which either the part of the lamp envelope opposite to the lamp cap or a 15: part of the lamp en~elope.situated near the lamp cap is mirrored. In the former case we have bowl-mirrored lamps :
in which a spherical or substantially spherical part of the lamp envelope is mirrored.and which are used in a reflector to obtain a narrow light beam; in the latter case 2Q. we have mirrored lamps whi~h produce a comparatively narrow light.beam without.further optical:auxiliary means. Among :
:these latter lamps:are~rirlg mirror lamps ha~ing a blown ~ lamp envelope the mirrored part:of which is usually curved : para~oloidally, and lamps ~rom pressed glass the lamp :25 envelope of which consists of a paraboloidal cup which is closed with a co~er glass.
For mirroring.a part of a lamp envelope,.aluminium or silver is:frequently used dué.to the high coefficient of reflection of said metals~, or chromium is used. Since much wood and leather is~used in t~e present-day interiors, larnps having silver coloured,~aluminium~ silyer, or chromium, : mirrors.are out of keepin~ in such interiors. Bowl mirrored lamps are nearly:always mounted so as to~be visible, :
whi]e ring mirror lamps and pressed glass lamps 1 1559~.~
PHN 9536 2 20.3.1980 are frequently used in luminaires only surrounding the lamp cap of the lamps.
In order -to remove the optically cold impression of mirrored lamps, such lamps are therefore provided with a gold coloured mirror. ~owever, the disadvantage of the use of gold is a high cost price and a poor adhesion of said metal to glass, so that after a small number of hours in operation a crackled effect is already obtained which adversely influences the concentrating effect of the mirror.
Other commercially~available lamps having a gold coloured mirror have been manufactured by vapour-deposit-ing alternately copper and cilver~or aluminium. ~or the benefit of a good adhesion sai.d materials must be vapour-deposited in very thin layers whi~ch are each not comple-tely dense, that is they do not have a uniform optical density throughout their surface so that several layer pairs must be provided so as -to obtain the desired effect.
This makes the manufacture of the lamps time-consuming 0 and experlsive, It is the object of the invention to provide mirror lamps in which on the one hand the disadvantage o~ silver-coloured mirrors is avoided and on the other hand the disadvantages of the use of gold or imita-tion 25~ gold~mirrors are avoided.
In elec-t~ric lamps of the kind described in the opening para~raph this object is achieved in that the metal layer is~silver coloured and that at least that part o~ the lamp envelope which is provided with the me-tal layer has a transparent smoke-colour.
In an embodiment of a lamp in accordance with the invention this has been reallsed by manufacturing the lamp envelope entirely or par-tly from smoke-coloured glass.
In another embodiment, however, the inner sur-face, the outer surface or -the inner and outer surface of the lamp envelope has a transparent, smoke-coloured layer. When only the inner surface has such a layer, the :. : .
1 ~55~Q~
PHN 9536 3 20.3.1980 mirror layer, of course, is present on the colour layer.
A smoke-coloured layer on the outer surface of the lamp envelope has the advantage that only one type of lamp need be manufactured of which a number may be provided with a coloured layer, as required, at the end of the production process~ whereas the remaining lamps can be sold as silver-ed lamps.
The colour layer may consist of a smoke-coloured enamel or of a smoke-coloured lacquer. As a lacquer are to be considered in particular silicone lacquers due to their stability at higher temperatures. They can easily ;~ be pro~ided by spraylng or dipping while diluted with solvents or be provided in an electrostatic coating process.
In bowl mirrored lamps in which the part of the lamp envelope situated opposite to the lamp cap is mirrored, it will nearly always suffice to colour the mirrored wall portlon~ for~example~by providing a colour layer on the outside of the lamp envelope. When placed in a luminaire,~
; bowl mirrored lamps hardly ever give the occasion of ob-~serving the insi~de~of'the mirror. Such a lamp~glves the impression of having a~gold mirror. Lamps having~a gold mirror give~light~o~'~a warmer~t~inge than Iamps having a silver-coloured~mirror. If~lt~is desired for lamps~accord~
;ing to the invention also to emit light of a warmer tinge~
~the wlndow of~th~è~;lamp~envelope;through which~the~ ght ;
emanates is also provided with a~`smoke-colouréd;layer.
5~ ~ In lamps in~whi'ch~a part of t~he lamp envelope ;
which is situated closer to the lamp cap is mirrored, it ~ ' wlll also suffioe to oolour the~mlrrored~wall~part.~ow~
ever, these lamps may also be~us~ed~so that the inside of the metal mirror can also be~observed.~Therefore, in this ~ ;
type of lamps the window of the lamp envelope~is prefe~
rably also coloured so as to give them a unive~rsal appli-cation as imitation gold mirror lamps.
In order to rnake a silve~r-coloured, silver, aluminium or chromium, mirror gold coloured, a slightly coloured coating layer or a slightlv coloured glass is sufficient. A smaLl series of tests will enable the exp~rt :
' .' ~ .. .
:~' 1 ~5590~
PHN 9536 4 20.3.1980 to determine the desired colour and colour intensity.
The measure used in lamps according to the invention is particularly suitable for incandescent lamps in which the electric element is a filament but is also suitable for discharge lamps in which -the electric element is a pair of electrodes in an ionisable gas, usually en-veloped by a discharge vessel.
Embodiments of lamps according to the invention are shown in the drawing. In the drawing lD Fig. 1 is an elevation, partly broken away, of a bowl mirrored incandescent lamps;
Fig. 2 is an elevation partly broken away of a pressed glass discharge lamp;
Fig. 3 is an elevation partly broken away of a .
lS ring mirror incandescent lamp.
~ In Fig. 1, the lamp envelope 1 is provided with ~ ;
a silver layer 4 over its part 2 situated opposite to the lamp cap 3. Part 2 is coated on its outside with a trans-parent smoke-coloured~iron oxide-eontaining enamel layer 5.
A filament 6 is accommodated~between current supply con~
duc~tors 7 and 8 which are connected to the lamp cap 3.
Between its ends the fil~ament 6 is supported by wires 9.
The lamp in Flg.~ 2 has a bipartite lamp envelope 20, 21 of press~ed glass.~The paraboloidal part 20 is~
25 ~covered with an alumlnlum~layer 22 and is mada of~smoke~
coloured glassO The cover~glass 21 is of colourless pressed glass. Connected to the lamp envelope lS~ a lamp cap 23 from which current suppl~ conductors 24 and 25 e~tend to a high pressure sodium vapour discharge vessel 26.~
The lamp envelope 30 in~Fig. 3 has a paraboloid-ally eurved lamp envelope part 31 which is eovered with an aluminium layer 32. Lamp envelope part 31, like window 33 and the neck-shaped part 34 of the lamp envelope, to which a lamp cap 35 is secured, is co~ered with a smoke~coloured lacquer layer 36. A filament which is hidden from view by the mirror 32 is supported by wires 37 a~d provided with current by current supply conductors 38 which are connected to the lamp cap 350 : . :
PHN 9536 5 20.3.1980 EXAMPLE.
Larnps as shown in ~ig. 3 having a larnp envelope with a largest diameter of 63 mm had an aluminium mirror vapour-deposited in a vacuum. The lamp envelope was dipped in a bath of 68 g of s:ilicone resin
2~1 g of orange dye solution 8 g of black dye solution 16.2 ml of xylene `
~ 3.2 ml of dlacetone alcohol~
2.1 ml of ethyl glycol acetate. ~-The lacquer was then dried at approximately40C for 5 minutes and baked at 300 C for 3 minutes.
In a p~rticular case the orange dye solution used was: ~ ;
5~ ~ 500 ~g~of zapon echt orange G
4.4 l of ethanol 6.4 l of ethyl glycol acetate and as a black dye solution:
500 g of~Neozapon blaok R~.E.
20~ 4.4~1;of~ethanol 6.4 l~o~ethyl glycol acetate.
Th2~lacquer~provided tha lamp with~a~brown-grey ~`~
to yello;~-grey~colour.
The larnps were~tested; ~or ~ :A ver~ ~good Go~lour~
25~ stability~was found. The lamps consumed~a~power~of 40 W
at~220 V. ;;
"Zapon~echt" and ~eozapon" are~registered~trade mark~s of BASF: They denote azodyes with complex bound chromium,~copper~and~oobalt.
....
, :: . .:
~ 3.2 ml of dlacetone alcohol~
2.1 ml of ethyl glycol acetate. ~-The lacquer was then dried at approximately40C for 5 minutes and baked at 300 C for 3 minutes.
In a p~rticular case the orange dye solution used was: ~ ;
5~ ~ 500 ~g~of zapon echt orange G
4.4 l of ethanol 6.4 l of ethyl glycol acetate and as a black dye solution:
500 g of~Neozapon blaok R~.E.
20~ 4.4~1;of~ethanol 6.4 l~o~ethyl glycol acetate.
Th2~lacquer~provided tha lamp with~a~brown-grey ~`~
to yello;~-grey~colour.
The larnps were~tested; ~or ~ :A ver~ ~good Go~lour~
25~ stability~was found. The lamps consumed~a~power~of 40 W
at~220 V. ;;
"Zapon~echt" and ~eozapon" are~registered~trade mark~s of BASF: They denote azodyes with complex bound chromium,~copper~and~oobalt.
....
, :: . .:
Claims (5)
1. An electric lamp having a sealed vacuum-tight glass lamp envelope through the wall of which current supply conductors to an electric element accommodated in the lamp envelope pass to the exterior where they are connected to a lamp cap secured to the lamp envelope, the wall of said lamp envelope being provided with a metal reflecting layer over a part of its inner surface, charac-terized in that the metal layer is silver coloured and that at least part of the lamp envelope which is provided with the metal layer has a transparent smoke-colour.
2. An electric lamp as claimed in Claim 1, charac-terized in that the smoke-colour is provided by a trans-parent smoke-coloured layer on the envelope.
3. An electric lamp as claimed in Claim 2, charac-terized in that the smoke-coloured layer is a lacquer layer.
4. An electric lamp as claimed in Claim 3, charac-terized in that the layer is provided on the outer surface of the lamp envelope
5. An electric lamp as claimed in Claim 2, 3 or 4 characterized in that the whole lamp envelope has a transparent smoke-colour.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL7905367 | 1979-07-10 | ||
| NL7905367A NL7905367A (en) | 1979-07-10 | 1979-07-10 | ELECTRIC LAMP WITH A MIRRORED LAMP BARREL. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1155901A true CA1155901A (en) | 1983-10-25 |
Family
ID=19833520
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000355320A Expired CA1155901A (en) | 1979-07-10 | 1980-07-03 | Electric lamp having a partly mirrored lamp envelope |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0022304B1 (en) |
| JP (1) | JPS5613661A (en) |
| CA (1) | CA1155901A (en) |
| DE (1) | DE3060917D1 (en) |
| NL (1) | NL7905367A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3340387A1 (en) * | 1983-11-08 | 1985-05-15 | Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH, 8000 München | ELECTRIC BULB AND METHOD FOR THE PRODUCTION THEREOF |
| US4536834A (en) * | 1984-05-22 | 1985-08-20 | General Electric Company | R lamp having an improved neck section for increasing the useful light output |
| US4656386A (en) * | 1985-03-13 | 1987-04-07 | General Electric Company | R lamp having an improved dome portion for increasing the useful light output |
| EP0237104B1 (en) * | 1986-03-11 | 1990-05-02 | Koninklijke Philips Electronics N.V. | Blown lamp bulb and electric lamp provided with such a bulb |
| DE3763511D1 (en) * | 1986-04-16 | 1990-08-09 | Philips Nv | ELECTRIC LAMP WITH MIRRORED PISTON. |
| US4803394A (en) * | 1987-02-25 | 1989-02-07 | U.S. Philips Corporation | Lamp vessel for multiple lamp types |
| US5789847A (en) * | 1994-09-09 | 1998-08-04 | Philips Electronics North America Corporation | High efficiency sealed beam reflector lamp with reflective surface of heat treated silver |
| DE19857076A1 (en) * | 1998-12-10 | 2000-06-15 | Volkswagen Ag | Incandescent lamp, for a car headlight, has a bulb coating which is black at the bulb side and silver at the opposite side |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2070700A (en) * | 1934-11-17 | 1937-02-16 | Welsbach Street Lighting Compa | Illumination |
| US2901655A (en) * | 1955-11-10 | 1959-08-25 | Gen Electric | Reflecting electric lamp |
| FR2256531A1 (en) * | 1973-12-26 | 1975-07-25 | Lampes Elect Fab Reunies | Electric bulb with silvered cap - light is doubly reflected before hitting socket |
-
1979
- 1979-07-10 NL NL7905367A patent/NL7905367A/en not_active Application Discontinuation
-
1980
- 1980-07-03 CA CA000355320A patent/CA1155901A/en not_active Expired
- 1980-07-07 JP JP9184480A patent/JPS5613661A/en active Pending
- 1980-07-07 EP EP80200654A patent/EP0022304B1/en not_active Expired
- 1980-07-07 DE DE8080200654T patent/DE3060917D1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| NL7905367A (en) | 1981-01-13 |
| EP0022304A1 (en) | 1981-01-14 |
| EP0022304B1 (en) | 1982-10-06 |
| JPS5613661A (en) | 1981-02-10 |
| DE3060917D1 (en) | 1982-11-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |