US4074167A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Halogen incandescent lamp
Assignee: US Philips Corp
•
Filing: 1976-11-16
•
Granted: 1978-02-14
•
Expires: 1996-11-16
Abstract
Abstract Halogen incandescent lamps having at least two filaments are provided with a hard-glass lamp vessel. In the vacuum-tight seal of the vessel molybdenum wire current leadthrough conductors are incorporated which form one assembly with internal and external current conductors. In spite of large differences between the coefficients of expansion of the glass and the molybdenum, the lacking of rotationally symmetric geometry at the area of the current leadthroughs and the high thermal load of the lamp vessel seal, the lamps have proved to be very reliable.
Inventors
- 👤 Cornelis P. van den Broek
- 👤 Johannes M. J. VAN Lieshout
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:37
CPC Classifications
H; H01; H01K; H01K1/00; H01K1/40; H01K1/38
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
236 words
A halogen incandescent lamp which comprises: a lamp vessel of a high-melting-point transparent material which is resistant to halogen, at least three molybdonum internal current conductors disposed in said vessel, at least two tungsten filaments stretched between said internal current conductors, said lamp vessel comprising a vacuum-tight seal having a plurality of current leadthrough conductors incorporated therein which are each in electrical contact with one of said internal current conductors, a plurality of external current conductors extending outside said lamp vessel, each of said external current conductors being connected to one of said leadthrough conductors, said lamp vessel being filled with a halogen-containing inert gas, said lamp vessel consisting of an alkali-alumino-borosilicate glass having a coefficient of expansion of 31 - 37 × 10 -7 ° C -1 at 0°-300° C, said internal current conductors being a molybdenum wire having a minimum diameter of 400 microns, a glass bead of the kind of glass from which the material of the lamp vessel is selected being disposed in surrounding vacuum tight relationship to at least the part of each of said molybdenum wires which extend in said vacuum-tight seal of said lamp, the ratio between the diameter of the molybdenum wires and the wall thickness of the glass bead being larger than 2 and the angles at which the glass of the lamp vessel contacts the glass of the bead, measured through glass, being at most 90°.
Claim 2
Dependent Claim
236 words
A halogen incandescent lamp which comprises: a lamp vessel of a high-melting-point transparent material which is resistant to halogen, at least three molybdonum internal current conductors disposed in said vessel, at least two tungsten filaments stretched between said internal current conductors, said lamp vessel comprising a vacuum-tight seal having a plurality of current leadthrough conductors incorporated therein which are each in electrical contact with one of said internal current conductors, a plurality of external current conductors extending outside said lamp vessel, each of said external current conductors being connected to one of said leadthrough conductors, said lamp vessel being filled with a halogen-containing inert gas, said lamp vessel consisting of an alkali-alumino-borosilicate glass having a coefficient of expansion of 31 - 37 × 10 -7 ° C -1 at 0°-300° C, said internal current conductors being a molybdenum wire having a minimum diameter of 400 microns, a glass bead of the kind of glass from which the material of the lamp vessel is selected being disposed in surrounding vacuum tight relationship to at least the part of each of said molybdenum wires which extend in said vacuum-tight seal of said lamp, the ratio between the diameter of the molybdenum wires and the wall thickness of the glass bead being larger than 2 and the angles at which the glass of the lamp vessel contacts the glass of the bead, measured through glass, being at most 90°.
Claim 3
Dependent Claim
51 words
A halogen incandescent lamp as claimed in claim 1, said glass of said lamp vessel mainly consists of 77-81% by weight of SiO 2 , 12-15% by weight of B 2 O 3 , 3-5.5% by weight of Na 2 O and 1.5-2.5% by weight of Al 2 O 3 .
Claim 4
Dependent Claim
36 words
A halogen incandescent lamp as claimed in claim 2 wherein the ratio between the diameter of said molybdenum wires and the wall thickness of the glass bead disposed in surrounding relationship is between 2 and 15.
Claim 5
Dependent Claim
39 words
A halogen incandescent lamp as claimed in claim 2 wherein the angle α at which the glass of the lamp vessel contacts the glass of the bead on the molybdenum wires inside the lamp vessel is at most 45°.
Claim 6
Dependent Claim
21 words
A halogen incandescent lamp as claimed in claim 1 wherein said molybdenum wires have a diameter of 600 to 800 microns.
References Cited (Backward Citations)
CA933577A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |