Patent US4177401A successfully refreshed from Google Patents.
US4177401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low pressure metal vapor discharge lamp with tubular member and magnetic means
Assignee: Hitachi Ltd
•
Filing: 1978-05-02
•
Granted: 1979-12-04
•
Expires: 1998-05-02
Abstract
Abstract A low pressure metal vapor discharge lamp has a discharge envelope of a double tube structure filled with an inert gas and a small quantity of metal. The discharge envelope comprises a sealed outer glass bulb, and an inner glass tube disposed within the outer glass bulb substantially concentrically therewith and having one open end and the other closed end. The lamp further has a single cathode inside the inner glass tube, a plurality of anodes disposed exteriorly of the inner glass tube and interiorly of the outer glass bulb, and a permanent magnet disposed near the open end of the inner glass tube for applying a magnetic field of a fixed intensity near the open end.
Inventors
- 👤 Mikiya Yamane
- 👤 Teruichi Tomura
- 👤 Yoshio Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 02:30
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/50; H01J61/00; H01J61/02; H01J61/04; H01J61/10; H01J61/103; H01J61/30; H01J61/34
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
94 words
A low pressure metal vapor discharge lamp comprising: a discharge envelope including an outer bulb made of light-transmissive material and an inner tube disposed within said outer bulb, said inner tube having one open end and the other closed end; an inert gas and metal filled in said envelope; a cathode disposed interiorly of said inner tube; an anode disposed exteriorly of said inner tube and interiorly of said outer bulb; and magnetic field applying means disposed near the open end of said inner tube for applying a magnetic field near the open end.
Claim 2
Dependent Claim
94 words
A low pressure metal vapor discharge lamp comprising: a discharge envelope including an outer bulb made of light-transmissive material and an inner tube disposed within said outer bulb, said inner tube having one open end and the other closed end; an inert gas and metal filled in said envelope; a cathode disposed interiorly of said inner tube; an anode disposed exteriorly of said inner tube and interiorly of said outer bulb; and magnetic field applying means disposed near the open end of said inner tube for applying a magnetic field near the open end.
Claim 3
Dependent Claim
30 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said magnetic field applying means includes a permanent magnet disposed near the open end of said inner tube.
Claim 4
Dependent Claim
38 words
A low pressure metal vapor discharge lamp according to claim 2, wherein said outer bulb emerges into a tubular recess which confronts the open end of said inner tube, and said permanent magnet is inserted in said recess.
Claim 5
Dependent Claim
24 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said anode is disposed near the closed end of said inner tube.
Claim 6
Dependent Claim
24 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said cathode is disposed near the closed end of said inner tube.
Claim 7
Dependent Claim
22 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said inner tube is disposed concentrically with said outer bulb.
Claim 8
Dependent Claim
20 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said inner tube is made of light-transmissive material.
Claim 9
Dependent Claim
24 words
A low pressure metal vapor discharge lamp according to claim 7, wherein said outer bulb has its inner surface coated with a phosphor film.
Claim 10
Dependent Claim
27 words
A low pressure metal vapor discharge lamp according to claim 8, wherein said inner tube has its inner surface and outer surface coated with a phosphor film.
Claim 11
Dependent Claim
20 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said outer bulb is made of light-transmissive glass.
Claim 12
Dependent Claim
20 words
A low pressure metal vapor discharge lamp according to claim 1, wherein said inner bulb is made of light-transmissive glass.
Claim 13
Dependent Claim
96 words
A low pressure metal vapor discharge lamp comprising: a discharge envelope including an outer bulb made of light-transmissive material and an inner tube disposed within said outer bulb, said inner tube having one open end and the other closed end; an inert gas and metal filled in said envelope; a cathode disposed interiorly of said inner tube; a plurality of anodes disposed exteriorly of said inner tube and interiorly of said outer bulb; and magnetic field applying means disposed near the open end of said inner tube for applying a magnetic field near the open end.
Claim 14
Dependent Claim
96 words
A low pressure metal vapor discharge lamp comprising: a discharge envelope including an outer bulb made of light-transmissive material and an inner tube disposed within said outer bulb, said inner tube having one open end and the other closed end; an inert gas and metal filled in said envelope; a cathode disposed interiorly of said inner tube; a plurality of anodes disposed exteriorly of said inner tube and interiorly of said outer bulb; and magnetic field applying means disposed near the open end of said inner tube for applying a magnetic field near the open end.
Claim 15
Dependent Claim
30 words
A low pressure metal vapor discharge lamp according to claim 12, wherein said magnetic field applying means includes a permanent magnet disposed near the open end of said inner tube.
Claim 16
Dependent Claim
26 words
A low pressure metal vapor discharge lamp according to claim 12, wherein the plurality of anodes are disposed near the closed end of said inner tube.
Claim 17
Dependent Claim
24 words
A low pressure metal vapor discharge lamp according to claim 12, wherein said cathode is disposed near the closed end of said inner tube.
Claim 18
Dependent Claim
22 words
A low pressure metal vapor discharge lamp according to claim 12, wherein said inner tube is disposed concentrically with said outer bulb.
Claim 19
Dependent Claim
20 words
A low pressure metal vapor discharge lamp according to claim 12, wherein said inner tube is made of light-transmissive material.
Claim 20
Dependent Claim
24 words
A low pressure metal vapor discharge lamp according to claim 17, wherein said outer bulb has its inner surface coated with a phosphor film.
Claim 21
Dependent Claim
27 words
A low pressure metal vapor discharge lamp according to claim 18, wherein said inner tube has its inner surface and outer surface coated with a phosphor film.
Claim 22
Dependent Claim
20 words
A low pressure metal vapor discharge lamp according to claim 12, wherein said outer bulb is made of light-transmissive glass.
Claim 23
Dependent Claim
20 words
A low pressure metal vapor discharge lamp according to claim 12, wherein said inner bulb is made of light-transmissive glass.
Claim 24
Dependent Claim
23 words
A low pressure metal vapor discharge lamp according to claim 12, further comprising at least one resistor coupled between the plurality of anodes.
Claim 25
Dependent Claim
23 words
A low pressure metal vapor discharge lamp according to claim 12, further comprising at least one transformer coupled between the plurality of anodes.
Claim 26
Dependent Claim
123 words
A low pressure mercury vapor discharge lamp comprising: a discharge envelope including an outer glass bulb and an inner glass tube disposed concentrically therewith, said inner glass tube having one open end and the other closed end; an inert gas and a small quantity of mercury filled in said envelope; a cathode disposed interiorly of said inner glass tube and near the closed end of said inner glass tube; a plurality of anodes disposed, near the closed end of said inner glass tube, exteriorly of said inner glass tube and interiorly of said outer glass bulb; and a permanent magnet disposed near the open end of said inner glass tube for applying a magnetic field of a fixed intensity near the open end.
Claim 27
Dependent Claim
123 words
A low pressure mercury vapor discharge lamp comprising: a discharge envelope including an outer glass bulb and an inner glass tube disposed concentrically therewith, said inner glass tube having one open end and the other closed end; an inert gas and a small quantity of mercury filled in said envelope; a cathode disposed interiorly of said inner glass tube and near the closed end of said inner glass tube; a plurality of anodes disposed, near the closed end of said inner glass tube, exteriorly of said inner glass tube and interiorly of said outer glass bulb; and a permanent magnet disposed near the open end of said inner glass tube for applying a magnetic field of a fixed intensity near the open end.
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) | 1982-12-03 | 1983-06-04 | 1983-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-03 | 1987-06-04 | 1987-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-03 | 1991-06-04 | 1991-12-04 | $7700.00 | Window Closed / Lapsed |