Patent US4243929A successfully refreshed from Google Patents.
US4243929A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recharging accumulator batteries
Assignee: MULTILAB AB
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Filing: 1978-01-17
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Granted: 1981-01-06
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Expires: 1998-01-17
Abstract
Abstract The voltage of a unit for recharging an accumulator battery is reduced to a low level when the battery is in a charged state as determined by a predetermined fall in the trickle charging current. When the charged state of the battery is no longer maintained as determined by a fall in battery voltage below the low voltage level and a predetermined increase in trickle charging current, the voltage of the unit changes to a high level.
Inventors
- 👤 Tibor Lenart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:54
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/90; H02J7/94; Y; Y10; Y10S; Y10S320/00; Y10S320/28
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
148 words
A battery charging circuit for recharging an accumulator battery with charging current comprising: a power supply for supplying power to the batttery to charge same, said supply being operable at two voltage levels; a current monitoring device for monitoring the charging current drawn by the battery; and a regulation circuit for receiving information from the current monitoring device and responding thereto to change the mode of operation of the power supply from the higher to the lower of said voltage levels when said charging current at said higher voltage level falls below a predetermined high current value, characterized by means in the regulation circuit for changing the mode of operation of power supply to said higher voltage level whenever said charging current, as sensed by said current monitoring device, rises above a predetermined low value, which is lower than said high current value, at said lower voltage level.
Claim 2
Dependent Claim
148 words
A battery charging circuit for recharging an accumulator battery with charging current comprising: a power supply for supplying power to the batttery to charge same, said supply being operable at two voltage levels; a current monitoring device for monitoring the charging current drawn by the battery; and a regulation circuit for receiving information from the current monitoring device and responding thereto to change the mode of operation of the power supply from the higher to the lower of said voltage levels when said charging current at said higher voltage level falls below a predetermined high current value, characterized by means in the regulation circuit for changing the mode of operation of power supply to said higher voltage level whenever said charging current, as sensed by said current monitoring device, rises above a predetermined low value, which is lower than said high current value, at said lower voltage level.
Claim 3
Dependent Claim
45 words
A circuit according to claim 1 wherein the power supply incorporates a rectifier bridge arranged to be supplied from a.c. source, characterized in that the power supply also incorporates an extra capacitance connected in parallel with the source via a switch of said regulation circuit.
Claim 4
Dependent Claim
56 words
A circuit according to claim 2, characterized in that the switch comprises contacts of a first relay which forms said current monitoring device, and a second relay is provided which is responsive to said higher voltage level to reduce the sensitivity of said first relay by connecting a resistor across the winding of the first relay.
Claim 5
Dependent Claim
119 words
A circuit according to claim 1, wherein said power supply provides a non-pulsating direct voltage via a collector-emitter path of a first transistor which is controlled by a second transistor, the base electrode of the second transistor being connected to an output of a first potential divider connected across the power supply output which is characterized in that there is provided a third transistor having an emitter-collector path, the direction of conduction of which is opposite to that of said first and said second transistors and which is connected between the power supply output and the base electrode of the second transistor via a first resistance, the base electrode of the third transistor being controlled by said regulation circuit.
Claim 6
Dependent Claim
96 words
A circuit according to claim 4, characterized in that said regulation circuit comprises a fourth transistor, the emitter-collector path of which is connected in parallel to the potential divider, the collector electrode of which is connected to the base electrode of the third transistor, and the base and emitter electrodes of which are connected to the emitter electrode of the first transistor via a second and third resistance respectively, said second resistance forming part of a second potential divider connected in parallel with the first potential divider, and said third resistance forming said current monitoring device.
Claim 7
Dependent Claim
124 words
A circuit according to claim 1, wherein said power supply is arranged to provide a voltage pulsating about the terminal voltage of the battery and is connected across the battery via a controlled rectifier, comparison circuit means for comparing the terminal voltage with a reference voltage at a potential divider only when the terminal voltage exceeds the pulsating voltage and, as a result of the comparison, bringing the rectifier to a conducting or non-conducting state and keeping it in such a state until the next comparison occurrence, characterized in that said current monitoring device comprises a capacitance which is connected via a charging circuit across the battery and controls the connection and disconnection of a shunting resistor across a portion of the potential divider.
Claim 8
Dependent Claim
20 words
A circuit according to claim 6, characterized in that connection of the shunt resistance is controlled by a shunting transistor.
Claim 9
Dependent Claim
44 words
A circuit according to claim 6, characterized in that the capacitance is provided with a discharging resistance in series with the collector-emitter path of a discharging transistor which is base-connected so as to be brought into the conducting state when the rectifier is conductive.
Claim 10
Dependent Claim
16 words
A circuit according to claim 6, characterized in that the charging current limits are continuously controllable.
Claim 11
Dependent Claim
24 words
A circuit according to claim 9, characterized in that charging and discharging resistances included in the charging and discharging circuits, respectively, form a potentiometer.
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) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |