US3736452A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Halogen motorcar lamp
Assignee: US Philips Corp
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Filing: 1971-09-24
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Granted: 1973-05-29
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Expires: 1991-09-24
Abstract
Abstract A halogen filament lamp having two filaments for motorcar headlights. The envelope comprises two cylindrical end portions and a rotationally symmetric widened intermediate part. By suitable choice of the location of the transition between the cylindrical top portion of the envelope and the widened part relative to the location between the end faces of the two filaments facing each other it is achieved that parasitic light sources emanating from the anti-dazzle filament which would supply a dazzling beam do not occur.
Inventors
- 👤 J Rijnders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:32
CPC Classifications
H; H01; H01K; H01K1/00; H01K1/28; H01K9/00; H01K9/08
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
164 words
A halogen filament lamp comprising: a lamp envelope having cylindrical end portions, said envelope having an outwardly bulging intermediate portion between the cylindrical end portions, said bulging intermediate portion being smoothly curved and symmetric about the longitudinal axis of the lamp; a filament for a driving light stretched axially in the envelope; a filament for an anti-dazzle light also stretched axially in the envelope, the intermediate portion of the envelope and one of said cylindrical end portions of the envelope proximate to said anti-dazzle filament forming a transition zone defining a plane which intersects the anti-dazzle filament approximately centrally between its ends, said two filaments being spaced apart and having the point approximately between the ends of the two filaments which face each other forming an apex of a cone, the cone having as a base said transition zone, the apical angle of the cone being between 80* and 100*; and a reflecting screen surrounding part of the circumferential region around the antidazzle filament.
Claim 2
Dependent Claim
164 words
A halogen filament lamp comprising: a lamp envelope having cylindrical end portions, said envelope having an outwardly bulging intermediate portion between the cylindrical end portions, said bulging intermediate portion being smoothly curved and symmetric about the longitudinal axis of the lamp; a filament for a driving light stretched axially in the envelope; a filament for an anti-dazzle light also stretched axially in the envelope, the intermediate portion of the envelope and one of said cylindrical end portions of the envelope proximate to said anti-dazzle filament forming a transition zone defining a plane which intersects the anti-dazzle filament approximately centrally between its ends, said two filaments being spaced apart and having the point approximately between the ends of the two filaments which face each other forming an apex of a cone, the cone having as a base said transition zone, the apical angle of the cone being between 80* and 100*; and a reflecting screen surrounding part of the circumferential region around the antidazzle filament.
Claim 3
Dependent Claim
79 words
A halogen lamp as claimed in claim 1 wherein said cone extends through said apex to form a conical surface inverted from said first cone, said inverted conical surface intersecting the intermediate portion of said envelope and forming a circle, said circle being transverse to the longitudinal axis of the tube, a lower portion of the envelope extending from a portion of said circle to the end of the cylindrical portion of the envelope having a light-impervious layer thereon.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |