Patent US3285293A successfully refreshed from Google Patents.
US3285293A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filament forming
Assignee: GTE Sylvania Inc
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Filing: 1966-01-03
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Granted: 1966-11-15
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Expires: 1986-01-03
Abstract
No abstract record available.
Inventors
- 👤 Wilfrid G Matheson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:20
CPC Classifications
H; H01; H01K; H01K3/00; H01K3/02; H01K3/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
75 words
THE METHOD OF FIXING THE SHAPE OF A TUNGSTEN WIRE COIL HAVING ENDS DISPOSED THEREIN, THE STEPS WHICH COMPRISE: PLACING SAID COIL ON A TIGHTLY FITTING REFRACTORY METAL MANDREL WITH THE ENDS OF SAID COIL BEING FREE, HEATING SAID COIL TO A TEMPERATURE BETWEEN ABOUT 2200*K. AND 2800* K. WHILE ON SAID MANDREL, COOLING SAID COIL, AND THEREAFTER REMOVING SAID REFRACTORY MANDREL AND MOUNTING THE COIL IN A LAMP BULB TO FORM A SEALED LAMP.
Claim 2
Independent Claim
75 words
THE METHOD OF FIXING THE SHAPE OF A TUNGSTEN WIRE COIL HAVING ENDS DISPOSED THEREIN, THE STEPS WHICH COMPRISE: PLACING SAID COIL ON A TIGHTLY FITTING REFRACTORY METAL MANDREL WITH THE ENDS OF SAID COIL BEING FREE, HEATING SAID COIL TO A TEMPERATURE BETWEEN ABOUT 2200*K. AND 2800* K. WHILE ON SAID MANDREL, COOLING SAID COIL, AND THEREAFTER REMOVING SAID REFRACTORY MANDREL AND MOUNTING THE COIL IN A LAMP BULB TO FORM A SEALED LAMP.
References Cited (Backward Citations)
GB267312A
Cited
US1826524A
Cited
US1976522A
Cited
US2441228A
Cited
US3048201A
Cited
US3059669A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-11-14 | 1970-05-16 | 1970-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-11-14 | 1974-05-16 | 1974-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-11-14 | 1978-05-16 | 1978-11-15 | $7700.00 | Window Closed / Lapsed |