Patent EP0465083A2 successfully refreshed from Google Patents.
EP0465083A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Discharge lamp with surrounding shroud and method of making such lamp
Assignee: General Electric Co
•
Filing: 1991-06-25
•
Granted: —
•
Expires: 2011-06-25
Abstract
Abstract This discharge lamp includes (i) an inner envelope (12) of vitreous material comprising a bulbous portion (14) and two tubular portions (16, 18) extending from the bulbous portion and (ii) a tubular shroud (20) of vitreous material surrounding the bulbous portion and the two tubular portions. The lamp is made by the following method. A disk-shaped enlargement (30) is formed in at least one of the tubular portions by heating a localized region of the tubular portion to its softening point and then subjecting said localized region to a compressive force (i) that is abruptly applied along the length of the tubular portion and (ii) that drives the softened vitreous material radially outward into a disk formation. Then the tubular shroud is placed over the inner envelope so that each disk-shaped enlargement is positioned with its outer periphery closely adjacent the inner periphery of the surrounding tubular shroud. Then seals are formed between the outer peripheries of the disk-shaped enlargements and the surrounding shroud portions by heating each of the surrounding shroud portions to its softening point and collapsing it about the outer periphery of the associated disk-shaped enlargement.
Inventors
- 👤 John Julius Biel
- 👤 John Martin Davenport
- 👤 Richard Lowell Hansler
- 👤 Paul George Hlahol
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-10 01:55
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/24; H01J9/32; H01J9/323; H01J61/00; H01J61/02; H01J61/30; H01J61/34
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
266 words
A method of making a discharge lamp that comprises (i) an inner envelope comprising a hollow bulbous portion of vitreous materal and two tubular portions of vitreous material joined to and extending in opposite directions from said bulbous portion and (ii) a tubular shroud of vitreous material surrounding said bulbous portion and said tubular portions, the method comprising: (a) forming a disk-shaped enlargement in each of said tubular portions by heating a localized region of the tubular portion to its softening point and then subjecting said softened localized region to a compressive force (i) that is abruptly applied along the length of said tubular portion and (ii) that drives the softened vitreous material radially outward into a disk formation, (b) placing said tubular shroud over said inner envelope so that each of said disk-shaped enlargements is positioned in alignment with a predetermined portion of said shroud and with the outer periphery of the enlargement closely adjacent but slightly spaced from the inner periphery of said predetermined shroud portion, thereby forming an unsealed chamber between said shroud and said inner envelope and between said disk-shaped enlargements, (c) forming a first seal between the inner periphery of one of said predetermined portions of the shroud and the outer periphery of the disk-shaped enlargement aligned therewith by heating and thereby softening said one predetermined shroud portion and then collapsing said one predetermined shroud portion about the outer periphery of said aligned enlargement, (d) forming a second seal between the inner periphery of the other of said predetermined shroud portions and the outer periphery of the disk-shaped enlargement aligned therewith.
Claim 2
Dependent Claim
16 words
A method as defined in claim 1 and further comprising the step of evacuating said chamber.
Claim 3
Dependent Claim
50 words
The method of claim 2 in which the evacuation step is carried out by causing flow to occur through a clearance space present between the outer periphery of said other disk-shaped enlargement and the inner periphery of the other of said predetermined shroud portions before said second seal is formed.
Claim 4
Dependent Claim
20 words
A method as defined in claim 1 and further comprising the step of filling said chamber with a gaseous fill.
Claim 5
Dependent Claim
50 words
The method of claim 4 in which said filling step is carried out by causing flow to occur through a clearance space present between the outer periphery of said other disk-shaped enlargement and the inner periphery of the other of said predetermined shroud portions before said second seal is formed.
Claim 6
Dependent Claim
38 words
The method of claim 1 in which said second seal is formed by heating and thereby softening said other predetermined shroud portion and then collapsing said other predetermined shroud portion about the outer periphery of said other enlargement.
Claim 7
Independent Claim
220 words
A method of making a discharge lamp that comprises (i) an inner envelope comprising a hollow bulbous portion of vitreous material and two tubular portions of vitreous material joined to and extending in opposite directions from said bulbous portion and (ii) a tubular shroud of vitreous material surrounding said bulbous portion and said tubular portions, the method comprising: (a) forming a disk-shaped enlargement in one of said tubular portions by heating a localized region of the tubular portion to its softening point and then subjecting said softened localized region to a compressive force (i) that is abruptly-applied along the length of said tubular portion and (ii) that drives the softened vitreous material radially outward into a disk formation, (b) placing said tubular shroud over said inner envelope so that said disk-shaped enlargement is positioned in alignment with a first predetermined portion of said shroud and with the outer periphery of the enlargement closely adjacent but slightly spaced from the inner periphery of said first predetermined shroud portion, and (c) forming a joint between the inner periphery of said first predetermined portion of the shroud and the outer periphery of the disk-shaped enlargement aligned therewith by heating and thereby softening said first predetermined shroud portion and then collapsing said first predetermined shroud portion about the outer periphery of said aligned enlargement.
Claim 8
Dependent Claim
57 words
A method as defined in claim 7 in which said tubular shroud when placed over said inner envelope includes a second predetermined portion surrounding the other of said tubular portions of said inner envelope, the method further comprising forming a second joint between said second predetermined shroud portion and said other tubular portion of said inner envelope.
Claim 9
Dependent Claim
42 words
The method of claim 8 in which said two joints constitute seals for a chamber located between said shroud and said inner envelope and between said disk-shaped enlargement and said second joint, the method further comprising the step of evacuating said chamber.
Claim 10
Dependent Claim
46 words
The method of claim 8 in which said two joints constitute seals for a chamber located between said shroud and said inner envelope and between said disk-shaped enlargement and said second joint, the method further comprising the step of filling said chamber with a gaseous fill.
Claim 11
Dependent Claim
126 words
A metal-halide discharge lamp comprising: (a) an inner envelope comprising: (a1) a hollow bulbous portion of vitreous material containing a fill including a metal halide, (a2) two tubular portions of vitreous material joined to and extending in opposite directions from said bulbous portion, (a3) a disk-shaped enlargement on one of said tubular portions of the same vitreous material as said one tubular portion projecting radially outward from said one tubular portion and integral therewith, and (b) a tubular shroud of vitreous material surrounding said inner envelope and having a predetermined portion surrounding and aligned with said disk-shaped enlargement, said predetermined shroud portion being collapsed about the outer periphery of the disk-shaped enlargement aligned therewtih and forming a joint with the outer periphery of said disk-shaped enlargement.
Claim 12
Dependent Claim
54 words
The lamp of claim 11 in which said predetermined shroud portion forms a seal with the outer periphery of said disk-shaped enlargement, and in which said shroud constitutes an outer wall and said disk-shaped enlargement constitutes an end wall of a chamber surrounding the tubular portions and the bulbous portion of said inner envelope.
Claim 13
Dependent Claim
91 words
The lamp as defined in claim 11, comprising (a) a disk-shaped enlargement on each of said tubular portions of the same vitreous material as the associated tubular portion projecting radially outward from said associated tubular portion and integral therewith, (b) said tubular shroud having predetermined portions respectively aligned with and collapsed about the outer periphery of the disk-shaped enlargement, and in which: (c) said shroud constitutes an outer wall and said disk-shaped enlargements constitute end walls of a chamber surrounding the tubular portions and the bulbous portion of said inner envelope.
Claim 14
Dependent Claim
132 words
A lamp as defined in any one of claims 11 to 13 and further comprising: (a) a pair of spaced-apart electrodes within said bulbous portion of said inner envelope, said electrodes having rod portions respectively extending from said bulbous portion into said tubular portions of the inner envelope and supported by the vitreous material of said tubular portions, (b) two conductive inleads respectively projecting into said tubular portions of the inner envelope from outside the inner envelope, (c) a foil member within each tubular portion of the inner envelope electrically connecting the associated inlead and the associated electrode rod portion, the vitreous material of said tubular portion being sealed to said foil member therein to form a foil seal, and (d) said disk-shaped enlargement(s) being located axially outward of said foil seal(s).
Claim 15
Dependent Claim
82 words
The lamp of anyone of claims 11 to 14 in which each of said disk-shaped enlargements is the product of an upsetting operation performed on its associated tubular member, the upsetting operation comprising heating a localized region of the tubular portion to its softening point and then subjecting said softened localized region to a compressive force (i) that is abruptly applied along the length of said tubular portion and (ii) that drives the softened vitreous material radially outward into a disk formation.
Claim 16
Dependent Claim
38 words
The lamp of any one of claims 11 to 15, in which said inner envelope and said shroud are of quartz, the quartz of said shroud having a substantially lower electronic conductivity than that of the inner envelope.
Claim 17
Dependent Claim
45 words
The lamp of any one of claims 11 to 16, in which: (a) said fill includes a sodium halide, and (b) said shroud is sufficiently large that the shroud temperature remains low enough during lamp operation to substantially prevent sodium loss from the inner envelope.
Claim 18
Dependent Claim
40 words
A vehicle headlamp comprising: (a) a reflector, (b) a lens at the front of the reflector, and (c) a lamp as defined in any one of claims 11 to 17, mounted in a position between said reflector and said lens.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.