US3795818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Emergency power supply
Assignee: SHETEC Inc
•
Filing: 1973-02-09
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Granted: 1974-03-05
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Expires: 1993-02-09
Abstract
Abstract The disclosed embodiment of the present invention is an auxiliary power supply which generally includes a battery, a relay for connecting the battery to an output in the absence of line voltage, and a circuit for charging the battery. The charging circuit includes a circuit for providing a relatively low charge rate to the battery and another circuit for providing a relatively high charge rate to the battery. A Schmitt trigger circuit is responsive to the voltage level of the battery for activating and deactivating the low charge rate circuit. A gate compares the voltage level of the battery with a reference voltage level to control the high charge rate circuit. Once the high charge circuit has been rendered inoperative during a particular period between line voltage failures, it remains inoperative. An interrogator circuit periodically draws a relatively small energy current pulse from the battery, thereby placing it under a load condition while the Schmitt trigger is sensing the voltage level of the battery. If, by virtue of the load condition, the voltage level of the battery drops below one of the trigger levels of the Schmitt circuit, the trigger circuit will activate the low charge circuit to charge the battery.
Inventors
- 👤 D Beaman
- 👤 J Shoberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:27
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/02; H02J2207/00; H02J2207/20
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
96 words
In an auxiliary power supply for connecting a battery to an output in the absence of line voltage, a circuit for charging the battery comprising a. a source of charging voltage, b. means for connecting said source to the battery, c. means for sensing the voltage level of the battery and energizing said connecting means in response thereto, and d. means for loading the battery for a relatively short time duration during the presence of said line voltage, whereby said sensing means is operative to sense the voltage level of the battery under a loaded condition.
Claim 2
Dependent Claim
96 words
In an auxiliary power supply for connecting a battery to an output in the absence of line voltage, a circuit for charging the battery comprising a. a source of charging voltage, b. means for connecting said source to the battery, c. means for sensing the voltage level of the battery and energizing said connecting means in response thereto, and d. means for loading the battery for a relatively short time duration during the presence of said line voltage, whereby said sensing means is operative to sense the voltage level of the battery under a loaded condition.
Claim 3
Dependent Claim
25 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 1, further comprising means for periodically energizing said loading means.
Claim 4
Dependent Claim
31 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 1, wherein said loading means includes means for drawing a pulse of current from the battery.
Claim 5
Dependent Claim
33 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 3, wherein said loading means further includes a switching element connecting said current drawing means across said battery.
Claim 6
Dependent Claim
25 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 4, further comprising means for periodically energizing said switching element.
Claim 7
Dependent Claim
37 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 5, wherein said current drawing means includes a resistor and capacitor connected in series with one another and with said switching element.
Claim 8
Dependent Claim
23 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 5, wherein said energizing means includes an oscillator.
Claim 9
Dependent Claim
94 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 1, wherein said sensing means includes a trigger circuit responsive to one voltage level for switching from a first output state to a second output state and responsive to another voltage level for switching from the second to the first output state, means responsive to one output state of said trigger circuit for connecting said charging source across the battery and responsive to the other output state of said trigger circuit for disconnecting said charging source from the battery.
Claim 10
Dependent Claim
39 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 8, wherein said loading means includes means for drawing a current pulse from the battery and means for periodically energizing said current drawing means.
Claim 11
Dependent Claim
113 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 9, wherein said current drawing means includes a first resistor and a capacitor connected in series with one another, a second resistor connected in parallel with said capacitor, and a switching element connecting the series connected first resistor and capacitor across the battery, and wherein said energizing means includes means for producing a pulse output having a predetermined period for periodically energizing said switching element, the time constant of said second resistor and said caPacitor being less than the period of said pulse output and being greater than the time constant of said first resistor and said capacitor.
Claim 12
Dependent Claim
36 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 1, wherein said connecting means includes a high charge rate circuit for connecting said source of charging voltage to the battery.
Claim 13
Dependent Claim
48 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 11, further comprising means connected to said high charge rate circuit for comparing the voltage level of the battery with a reference voltage and for controlling said high rate circuit in accordance therewith.
Claim 14
Dependent Claim
36 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 12, further comprising means for disabling said high charge rate circuit after the voltage of the battery attains a predetermined value.
Claim 15
Dependent Claim
131 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 1, wherein said connecting means includes a first impedance element connectable between said source and the battery, and a high charge rate circuit including a second impedance element connectable between said source and the battery and having a value of impedance less than the impedance value of said first impedance element, said high charge rate circuit including a switching element connecting said second impedance element between said source and the battery in one state thereof, said means for sensing the voltage level of the battery providing a control signal when voltage of the battery is less than a predetermined value, said switching element being responsive to said control signal for changing to said one state thereof.
Claim 16
Dependent Claim
54 words
A circuit for charging the battery in an auxiliary power supply as defined in claim 14, further comprising memory means connecting said control signal to said switching element, said memory means including means for disabling said high charge circuit after the voltage of the battery attains a certain value higher than said predetermined value.
References Cited (Backward Citations)
US3659181A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-04 | 1977-09-03 | 1978-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-04 | 1981-09-03 | 1982-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-04 | 1985-09-03 | 1986-03-05 | $7700.00 | Window Closed / Lapsed |