US3733535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Battery charger
Assignee: Individual
•
Filing: 1972-01-03
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Granted: 1973-05-15
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Expires: 1992-01-03
Abstract
Abstract This invention utilizes an SCR controlled charging circuit in which the on-off condition of the SCR is controlled by a transistor which conducts responsive to battery terminal voltage and which utilizes a capacitor between the gate lead of the SCR and the anode of the SCR to anticipate voltage fluctuations and eliminate r-f interference.
Inventors
- 👤 G Ballman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:53
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/90; H02J7/96; Y; Y10; Y10S; Y10S320/00; Y10S320/11
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
267 words
A battery charger comprising a pair of terminals attached to the positive and negative poles of a battery; a voltage divider circuit including a pair of resistors in series across said terminals and being provided with a central voltage reference point; Zener reference circuit also connected across the terminals and including a Zener in series with a dropping resistor, and also including a cathode directly connected to the negative battery terminal; transformer means coupled to a source of alternating current power and including a secondary winding; a blocking diode in series with a fourth resistor, all connected across the secondary winding, the cathode of the blocking diode being connected to one terminal of the fourth resistor, and the other terminal of said fourth resistor being connected to one terminal of the secondary winding and the negative terminal of the battery; an SCR including an anode connected to the other terminal of the secondary winding and to the anode of the blocking diode, said SCR also including a cathode connected to the positive battery terminal, and further including a gate lead; a capacitor connected between the cathode of the blocking diode and the gate lead; and transistor means including a base connected to the central voltage reference point, an emitter connected to the Zener anode, and a collector operatively connected to the gate lead through a fifth resistor; said transistor means being normally non-conducting but said central voltage reference point and Zener reference voltage being preselected so that the transistor means will go into conduction when the battery attains a terminal voltage indicative of a fully charged conditiOn.
Claim 2
Dependent Claim
267 words
A battery charger comprising a pair of terminals attached to the positive and negative poles of a battery; a voltage divider circuit including a pair of resistors in series across said terminals and being provided with a central voltage reference point; Zener reference circuit also connected across the terminals and including a Zener in series with a dropping resistor, and also including a cathode directly connected to the negative battery terminal; transformer means coupled to a source of alternating current power and including a secondary winding; a blocking diode in series with a fourth resistor, all connected across the secondary winding, the cathode of the blocking diode being connected to one terminal of the fourth resistor, and the other terminal of said fourth resistor being connected to one terminal of the secondary winding and the negative terminal of the battery; an SCR including an anode connected to the other terminal of the secondary winding and to the anode of the blocking diode, said SCR also including a cathode connected to the positive battery terminal, and further including a gate lead; a capacitor connected between the cathode of the blocking diode and the gate lead; and transistor means including a base connected to the central voltage reference point, an emitter connected to the Zener anode, and a collector operatively connected to the gate lead through a fifth resistor; said transistor means being normally non-conducting but said central voltage reference point and Zener reference voltage being preselected so that the transistor means will go into conduction when the battery attains a terminal voltage indicative of a fully charged conditiOn.
Claim 3
Dependent Claim
126 words
A battery charger comprising a pair of terminals attached to the positive and negative poles of a battery, first switching means including a control electrode for supplying charging current from a source to the battery terminals, second switching means operatively connected to the control electrode and to the battery terminals for actuating the flow of charging current to the battery through the first switching means when the battery terminal voltage is below a predetermined magnitude and also for stopping the flow of charging current through the first switching means when the battery terminal voltage exceeds that predetermined magnitude, a diode and resistor connected in series across the source, and a capacitor connected across the control electrode and the common connection of the diode and the resistor.
Claim 4
Dependent Claim
126 words
A battery charger comprising a pair of terminals attached to the positive and negative poles of a battery, first switching means including a control electrode for supplying charging current from a source to the battery terminals, second switching means operatively connected to the control electrode and to the battery terminals for actuating the flow of charging current to the battery through the first switching means when the battery terminal voltage is below a predetermined magnitude and also for stopping the flow of charging current through the first switching means when the battery terminal voltage exceeds that predetermined magnitude, a diode and resistor connected in series across the source, and a capacitor connected across the control electrode and the common connection of the diode and the resistor.
Claim 5
Dependent Claim
21 words
The charger of claim 2 wherein the first switching means comprises an SCR with the control electrode being the gate thereof.
Claim 6
Dependent Claim
77 words
The charger of claim 2 wherein the first switching means comprises an SCR with the control electrode being the gate thereof, and the second switching means is a normally off transistor, which derives its turn-on voltage from the terminals of the battery as the battery takes the charge, the collector of the transistor being directly connected to the gate of the SCR, and the collector current being derived from the cathode to gate leakage of the SCR.
Claim 7
Dependent Claim
101 words
The charger of claim 2 wherein the first switching means comprises an SCR with the control electrode being the gate thereof, the second switching means is a normally off transistor, which derives its turn-on voltage from the terminals of the battery as the battery takes the charge, the collector of the transistor being directly connected to the gate of the SCR, and the collector current being derived from the cathode to gate leakage of the SCR, the anode of the diode is directly connected to the anode of the SCR, and the capacitor is connected to the cathode of the diode.
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) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |