US4076992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum tube grid structures of phosmic bronze having copper and copper alloy conical supports
Assignee: RCA Corp
•
Filing: 1976-06-22
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Granted: 1978-02-28
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Expires: 1996-06-22
Abstract
Abstract A vacuum tube includes a cylindrical cathode around which a frusto-conical control grid extends. The control grid, which is made out of Phosnic bronze, has its larger diameter end attached to the smaller end of a first hollow truncated copper cone. A cylindrical Phosnic bronze screen grid extends coaxially around the control grid. One end of the screen grid is attached to the smaller diameter end of a second hollow truncated cone. The second cone extends around the first cone and is made out of a copper clad alloy of cobalt, nickel and iron. An anode encircles the screen grid.
Inventors
- 👤 John Thomas Mark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:55
CPC Classifications
H; H01; H01J; H01J21/00; H01J21/02; H01J21/06; H01J21/10; H01J19/00; H01J19/28; H01J19/38
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
105 words
A vacuum tube comprising: a cylindrical cathode; a frusto-conical Phosnic bronze control grid extending coaxially around the cathode; a first hollow truncated cone having it smaller diameter end attached to the larger diameter end of the control grid, the first cone being made of a copper; a cylindrical Phosnic bronze screen grid extending coaxially around the control grid; a second hollow truncated cone having its smaller diameter end attached to one end of the screen grid and extending around the first cone, the second cone being made of a copper clad alloy of cobalt, nickel and iron; and an anode extending around the screen grid.
Claim 2
Dependent Claim
105 words
A vacuum tube comprising: a cylindrical cathode; a frusto-conical Phosnic bronze control grid extending coaxially around the cathode; a first hollow truncated cone having it smaller diameter end attached to the larger diameter end of the control grid, the first cone being made of a copper; a cylindrical Phosnic bronze screen grid extending coaxially around the control grid; a second hollow truncated cone having its smaller diameter end attached to one end of the screen grid and extending around the first cone, the second cone being made of a copper clad alloy of cobalt, nickel and iron; and an anode extending around the screen grid.
Claim 3
Dependent Claim
42 words
The vacuum tube as in claim 1 wherein the cylindrical cathode comprises a tungsten matrix formed of a porous tungsten cylinder filled with barium oxide, aluminum oxide and calcium oxide in molar ratios selected from the group consisting of 5:3:2 and 4:1:1.
Claim 4
Dependent Claim
26 words
The device as in claim 1 wherein the first cone has an inner and an outer copper cladding each comprising approximately 10% of the cone's thickness.
Claim 5
Dependent Claim
17 words
The tube as in claim 1 wherein the first and second cones are of substantially equal thickness.
Claim 6
Dependent Claim
21 words
The tube as in claim 1 wherein the thickness ratio of the control grid to the screen grid is about 2:3.
Claim 7
Dependent Claim
42 words
The tube as in claim 5 wherein the thickness of the control grid is between 18 and 20 mils (about 457 and 508 microns) and the thickness of the screen grid is between 27 and 31 mils (about 686 and 787 microns).
Claim 8
Dependent Claim
33 words
The tube as in claim 6 wherein the spacing between the control grid and the cathode and the screen grid and the control grid is equal to approximately 15 mils (approximately 381 microns).
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |