US3854964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lead silicate high voltage vacuum tube glass envelope
Assignee: General Electric Co
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Filing: 1973-09-24
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Granted: 1974-12-17
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Expires: 1993-09-24
Abstract
Abstract Glass composition having a high absorption of X-radiation, particularly in the wavelength region from 0.3 - 0.7 A, for use in fabricating high voltage vacuum tube glass envelopes. The glass compositions are a type of lead oxide containing glass which can be characterized as having an aggregate content of barium oxide with antimony oxide and cadmium oxide in excess of 10% by weight and further having an aggregate content of lead oxide with barium oxide, antimony oxide and cadmium oxide in excess of 55% by weight.
Inventors
- 👤 G Thomas
- 👤 L Reitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:30
CPC Classifications
C; C03; C03C; C03C4/00; C03C4/08; C03C4/087; C03C3/00; C03C3/04; C03C3/062; C03C3/07
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
116 words
IN A HIGH VOLTAGE VACUUM TUBE HAVING A GLASS ENVELOPE, THE IMPROVEMENT IN WHICH SAID GLASS ENVELOPE IS A GLASS WHICH IS HIGHLY ABSORBENT TO X-RADIATION IN THE WAVELENGTH RANGE FROM 0.3 - 0. 7 CONSISTING OF, BY WEIGHT: 30-40% SIO2, 3-7% K2O, 0-2% NA2O, 0-3% AI2O3, 35:50% PHO, 0-15% BAO, 0-15% SB2O3, AND 0-15% CDE WHEREIN THE AGGREGATE TOTAL OF BAO + SB2O3 + CDO IS GREATER THAN 10% AND THE AGGREGATE TOTAL OF PBO + BAO + SB2O3 + CDO IS GREATER THAN 55%, SAID GLASS HAVING AN AVERAGE COEFFICIENT OF THERMAL EXPANSION OVER THE RANGE 0* TO 300:C FROM 85 TO 93 X 10 **7 CM/CM/*C AND A WORKING RANGE GREATER THAN 240*C.
Claim 2
Dependent Claim
116 words
IN A HIGH VOLTAGE VACUUM TUBE HAVING A GLASS ENVELOPE, THE IMPROVEMENT IN WHICH SAID GLASS ENVELOPE IS A GLASS WHICH IS HIGHLY ABSORBENT TO X-RADIATION IN THE WAVELENGTH RANGE FROM 0.3 - 0. 7 CONSISTING OF, BY WEIGHT: 30-40% SIO2, 3-7% K2O, 0-2% NA2O, 0-3% AI2O3, 35:50% PHO, 0-15% BAO, 0-15% SB2O3, AND 0-15% CDE WHEREIN THE AGGREGATE TOTAL OF BAO + SB2O3 + CDO IS GREATER THAN 10% AND THE AGGREGATE TOTAL OF PBO + BAO + SB2O3 + CDO IS GREATER THAN 55%, SAID GLASS HAVING AN AVERAGE COEFFICIENT OF THERMAL EXPANSION OVER THE RANGE 0* TO 300:C FROM 85 TO 93 X 10 **7 CM/CM/*C AND A WORKING RANGE GREATER THAN 240*C.
Claim 3
Dependent Claim
16 words
A vacuum tube as defined in claim 1 wherein the glass contains 5-10% BaO by weight.
Claim 4
Dependent Claim
16 words
A vacuum tube as defined in claim 1 wherein the glass contains 2-3% Al2O3 by weight.
Claim 5
Dependent Claim
19 words
A vacuum tube as defined in claim 1 wherein the glass has a working range from 250*C to 300*C.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |