Patent US3814974A successfully refreshed from Google Patents.
US3814974A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cathode gun device
Assignee: Raytheon Co
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Filing: 1973-04-09
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Granted: 1974-06-04
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Expires: 1993-04-09
Abstract
Abstract A cathode gun device having a heat shield for improved operating efficiency is disclosed. The device includes a tubular cathode electrode and a thin metal foil made of low thermal conductivity and low emissivity material coiled about the cathode electrode for reflecting heat back to the cathode and conducting a minimum of heat. The foil has projections on a surface so as to separate adjacent coil surfaces from each other.
Inventors
- 👤 A Basiulis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:03
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J23/00; H01J23/02; H01J23/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
167 words
A cathode gun device for use in a traveling-wave tube comprising: a cathode for being heated to thermionic emission temperature; a tubular cathode support member having one end coupled to said cathode; a metal foil being coiled about itself several times and being disposed about said cathode support member forming an effective plurality of heat shields; said foil having a substantially thin cross-sectional area for minimizing heat transfer by conduction perpendicular to said area; said foil being relatively long in length for having a relatively long heat conduction path; said foil having a relatively low thermal conductivity constant for minimizing thermal transfer by conduction along the length of said foil; said foil having projections from a selected surface for substantially separating adjacent coils and minimizing thermal transfer by conduction therebetween; said foil having a polished surface for effectively reflecting heat from said surface; said foil having a relatively low emissivity for minimizing thermal transfer by radiation; and means for mounting said foil to said cathode support member.
Claim 2
Dependent Claim
167 words
A cathode gun device for use in a traveling-wave tube comprising: a cathode for being heated to thermionic emission temperature; a tubular cathode support member having one end coupled to said cathode; a metal foil being coiled about itself several times and being disposed about said cathode support member forming an effective plurality of heat shields; said foil having a substantially thin cross-sectional area for minimizing heat transfer by conduction perpendicular to said area; said foil being relatively long in length for having a relatively long heat conduction path; said foil having a relatively low thermal conductivity constant for minimizing thermal transfer by conduction along the length of said foil; said foil having projections from a selected surface for substantially separating adjacent coils and minimizing thermal transfer by conduction therebetween; said foil having a polished surface for effectively reflecting heat from said surface; said foil having a relatively low emissivity for minimizing thermal transfer by radiation; and means for mounting said foil to said cathode support member.
Claim 3
Dependent Claim
22 words
The invention according to claim 1 wherein said means for mounting said foil comprises welding said foil to said cathode support member.
Claim 4
Dependent Claim
27 words
The invention according to claim 1 wherein said means for mounting said foil comprises a sleeve member positioned to secure said foil to said cathode support member.
Claim 5
Dependent Claim
25 words
The invention according to claim 1 wherein said metal foil is a metal selected from the group consisting of: rhenium, columbium, tantalum, molybdenum and tungsten.
Claim 6
Dependent Claim
160 words
A cathode gun device for conserving power in a traveling-wave tube comprising: a cathode for being heated to thermionic emission temperature; a tubular cathode support member having said cathode mounted on one end; a metal foil coiled about itself a plurality of times and disposed about said cathode support member to form an effective plurality of heat shields; said foil being relatively long in length for providing a relatively long heat conduction path; said foil having a substantially thin cross-sectional area for minimizing heat transfer by conduction along the length of said foil; said foil having a relatively low thermal conductivity constant for minimizing thermal transfer by conduction along the length of said foil; said foil having projections from a surface for substantially separating adjacent coils and minimizing thermal transfer by conduction therebetween; said foil having a polished surface for effectively reflecting heat from said surface; and said foil having a relatively low emissivity for minimizing thermal transfer by radiation.
Claim 7
Dependent Claim
160 words
A cathode gun device for conserving power in a traveling-wave tube comprising: a cathode for being heated to thermionic emission temperature; a tubular cathode support member having said cathode mounted on one end; a metal foil coiled about itself a plurality of times and disposed about said cathode support member to form an effective plurality of heat shields; said foil being relatively long in length for providing a relatively long heat conduction path; said foil having a substantially thin cross-sectional area for minimizing heat transfer by conduction along the length of said foil; said foil having a relatively low thermal conductivity constant for minimizing thermal transfer by conduction along the length of said foil; said foil having projections from a surface for substantially separating adjacent coils and minimizing thermal transfer by conduction therebetween; said foil having a polished surface for effectively reflecting heat from said surface; and said foil having a relatively low emissivity for minimizing thermal transfer by radiation.
Claim 8
Dependent Claim
25 words
The invention according to claim 5 wherein said metal foil is a metal selected from the group consisting of: rhenium, columbium, tantalum, molybdenum and tungsten.
References Cited (Backward Citations)
US2899591A
Cited
US2391927A
Cited
US2518879A
Cited
US2577239A
Cited
US2888592A
Cited
US3204140A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |