Patent US3577003A successfully refreshed from Google Patents.
US3577003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic battery-switching device
Assignee: Union Carbide Corp
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Filing: 1969-03-11
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Granted: 1971-05-04
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Expires: 1989-03-11
Abstract
Abstract An apparatus for automatically switching off a working battery and switching on a standby battery when the working battery falls below a predetermined working voltage. The device utilizes at least one switching element such as a transistor associated with the working battery and at least one switching element such as a transistor associated with the standby battery, with the transistor associated with the working battery being connected so as to back bias the transistor associated with the standby battery. When the working battery wears down to a predetermined voltage its back bias is reduced to a sufficient point so as to turn on the standby transistor and thereby switch on the standby battery.
Inventors
- 👤 Byron C Behr
- 👤 Gunars Sprogis
- 👤 Frederick E Booth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:21
CPC Classifications
H; H02; H02J; H02J9/00; H02J9/04; H02J9/06; H02J9/061; Y; Y02; Y02B; Y02B70/00; Y02B70/30; Y04; Y04S; Y04S20/00; Y04S20/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
21 words
A switching device as in claim 1, further including a voltage-divider network connected between the standby battery and the fourth battery.
Claim 2
Dependent Claim
39 words
A switching device as in claim 1, further including an electrical indicator means connected between the load and said first and second transistors for indicating whether the working battery or the standby battery is delivering power to the load.
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) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |