US3778634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power supply with battery backup
Assignee: Schneider Electric Systems USA Inc
•
Filing: 1973-05-18
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Granted: 1973-12-11
•
Expires: 1993-05-18
Abstract
Abstract A power supply configuration is shown which provides for the addition of battery backup capabilities without unnecessary conversions or hardware. This configuration includes logic circuitry for automatically activating the backup unit in case of line voltage failure while disabling the backup unit in case of a short circuit.
Inventors
- 👤 J Hanrihan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:44
CPC Classifications
H; H02; H02J; H02J9/00; H02J9/04; H02J9/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
75 words
A power supply with backup capabilities for supplying several voltage levels of system power, comprising: a main power transformer having two primary and one secondary windings; means connected to the secondary winding for rectifying and regulating the transformer output; means for applying AC voltage to the first primary winding during the normal mode of operation of the power supply; and means for applying chopped DC voltage to the second primary winding during the backup mode.
Claim 2
Dependent Claim
75 words
A power supply with backup capabilities for supplying several voltage levels of system power, comprising: a main power transformer having two primary and one secondary windings; means connected to the secondary winding for rectifying and regulating the transformer output; means for applying AC voltage to the first primary winding during the normal mode of operation of the power supply; and means for applying chopped DC voltage to the second primary winding during the backup mode.
Claim 3
Dependent Claim
29 words
The power supply claimed in claim 1 further comprising: means to detect line voltage failure; and means to automatically activate the backup mode upon detection of line voltage failure.
Claim 4
Dependent Claim
31 words
The power supply claimed in claim 2 further comprising: means to disable the backup mode upon detection of a line voltage drop due to the loading effect of a short circuit.
Claim 5
Dependent Claim
26 words
The power supply claimed in claim 2 further comprising: a short circuit sensor for disabling the backup mode if line current increases above a predetermined maximum.
Claim 6
Dependent Claim
28 words
The power supply claimed in claim 1 wherein the DC means includes: a battery; and DC/DC converter means for converting the battery voltage to a chopped DC voltage.
Claim 7
Dependent Claim
53 words
The power supply claimed in claim 5 wherein the AC means further includes: line voltage detecting means for detecting line voltage above a predetermined minimum; and isolation switch means activated by the line voltage detecting means for applying AC voltage to the first primary winding when line voltage is detected above the minimum.
Claim 8
Dependent Claim
95 words
The supply claimed in claim 6 wherein the DC means further includes: short circuit detecting means for detecting an increase of line current above a predetermined maximum; disabling switch means activated by the short circuit means to open when line current above the maximum is detected; activation switch means in series with the disabling switch means activated by the line voltage detecting means to close when line voltage below the minimum is detected; and isolation relay means to activate the backup mode when the activation switch means and the disabling switch means are both closed.
Claim 9
Dependent Claim
28 words
The power supply claimed in claim 1 further comprising: means to prevent the simultaneous application of the AC voltage and the DC voltage to the main power transformer.
References Cited (Backward Citations)
US3196336A
Cited
US3293530A
Cited
US3339080A
Cited
US3373313A
Cited
US3509357A
Cited
US3614461A
Cited
US3703644A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |