US3862448A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Colour picture tube including shadow mask having self-compensation function for thermal stress
Assignee: Hitachi Ltd
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Filing: 1972-08-31
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Granted: 1975-01-21
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Expires: 1992-08-31
Abstract
Abstract The peripheral portion of a shadow mask which is spot welded to a supporting frame is provided with a plurality of openings so as to form a cushion zone for absorbing and minimizing the stress created therein by heat.
Inventors
- 👤 Tomio Ishizuka
- 👤 Hiromi Kanai
- 👤 Takao Kawamura
- 👤 Kenichi Fukuzawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:24
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/06; H01J29/07; H01J29/073; H01J2229/00; H01J2229/07; H01J2229/0727; H01J2229/0766; H01J2229/0772
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
95 words
In a color picture tube comprising a colour selection electrode assembly including an integrally formed operating portion adapted to transmit an electron beam, a peripheral portion surrounding said operating portion and a side portion; and a supporting frame welded to said side portion, the improvement which comprises a cushion zone formed by weakening the mechanical strength continuously over the area of thermal stress transmission in said peripheral portion and said side portion through provision of a uniformly distributed plurality of small blind openings over said area to obviate maldistribution of thermal stress in the mask.
Claim 2
Dependent Claim
95 words
In a color picture tube comprising a colour selection electrode assembly including an integrally formed operating portion adapted to transmit an electron beam, a peripheral portion surrounding said operating portion and a side portion; and a supporting frame welded to said side portion, the improvement which comprises a cushion zone formed by weakening the mechanical strength continuously over the area of thermal stress transmission in said peripheral portion and said side portion through provision of a uniformly distributed plurality of small blind openings over said area to obviate maldistribution of thermal stress in the mask.
Claim 3
Dependent Claim
90 words
In a color picture tube comprising a colour selection electrode assembly including an integrally formed operating portion adapted to transmit an electron beam, a peripheral portion surrounding said operating portion and a side portion; and a supporting frame welded to said side portion, the improvement which comprises a cushion zone formed by weakening the mechanical strength continuously over the area of thermal stress transmission in said peripheral portion and said side portion through provision of a reduced thickness over said area to obviate maldistribution of thermal stress in the mask.
Claim 4
Dependent Claim
90 words
In a color picture tube comprising a colour selection electrode assembly including an integrally formed operating portion adapted to transmit an electron beam, a peripheral portion surrounding said operating portion and a side portion; and a supporting frame welded to said side portion, the improvement which comprises a cushion zone formed by weakening the mechanical strength continuously over the area of thermal stress transmission in said peripheral portion and said side portion through provision of a reduced thickness over said area to obviate maldistribution of thermal stress in the mask.
References Cited (Backward Citations)
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US3524974A
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US3660708A
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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) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |