IMPROVED BATTERY-CHARGING CIRCUIT WITH LOCKING AND RESETTING MEANS

• US 3,603,862 A
• Filed: 12/22/1969
• Issued: 09/07/1971
• Est. Priority Date: 12/22/1969
• Status: Expired due to Term

• Current Assignee: Ralph r. Sherman, Jr., Robert F. Chase
• Original Assignee: Ralph r. Sherman, Jr., Robert F. Chase
• Inventors: Sherman, Ralph R. Jr., Chase, Robert F.
• Primary Examiner(s): Beha, Jr., William H.
• Assistant Examiner(s): Gunther, John M.
• Application Number:
  US04/886,971
• Time in Patent Office: 624 Days
• Field of Search: 320/DIG.2,39,40.31,35,36,22,23,24
• US Class Current: 320/158
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

A battery-charging circuit provides a main-charging current to a connected battery until the battery voltage reaches a selected magnitude, after which the charging circuit switches and provides a trickle-charge current to the battery. The charging circuit cannot provide main-charging current again until the battery is disconnected, and a battery subsequently connected to the charging circuit.

Claims

1. An improved battery charging circuit comprising:

a. main-charging means for supplying a main current to a battery connected to said charging circuit;

b. trickle-charging means for supplying a trickle current to said battery;

c. switching means connected to said main-charging means, said switching means having a normal condition that permits said main-charging means to supply said main current to said battery, and having a switched condition that causes said maincharging means to supply a reduced current to said battery in response to said battery having a voltage that exceeds a selected magnitude;

d. locking means connected to said switching means for maintaining said switching means in said switched condition after being switched;

e. and resetting means connected to said locking means for rendering said locking means inoperative in response to said battery being disconnected from said charging circuit, thereby permitting said switching means to return to said normal condition so that said main-charging means can supply main current to a battery connected to said charging circuit.

2. The improved battery-charging circuit of claim 1 wherein said main-charging means include a current-limiting device.

3. The improved battery-charging circuit of claim 1 wherein said switched condition of said switching means causes said main-charging means to supply substantially no current to said battery in response to said battery having a voltage that exceeds a selected magnitude.

4. The improved battery-charging circuit of claim 1 wherein said switching means have delay means to prevent said switching means from switching to said switched condition until said battery voltage exceeds said selected magnitude for a selected time.

5. The improved battery-charging circuit of claim 1 wherein said switched condition of said switching means causes said main charging means to supply substantially no current to said battery in response to said battery having a voltage that exceeds a selected magnitude, and wherein said switching means have delay means to prevent said switching means from switching to said switched condition until said battery voltage exceeds said selected magnitude for a selected time.

6. An improved circuit for charging a battery comprising:

a. first and second terminals for connection to a suitable source of charging current;

b. third and fourth terminals for connection to a battery to be charged;

c. first means connecting said second and fourth terminals;

d. second means having a main current path and a control terminal, said main current path being connected between said first and third terminals for supplying a main charging current to a connected battery;

e. third means connected between said first and third terminals for supplying a trickle-charging current to a connected battery;

f. fourth means connected to said control terminal for normally causing said second means to conduct a main-charging current through said main-current path;

g. fifth means connected to said third terminal and to said control terminal for effecting a reduction of said main-charging current in response to a voltage of selected magnitude at said third terminal;

h. and sixth means connected to said fifth means for rendering said fifth means inoperative in response to the absence of a battery between said third and fourth terminals, and thereby permit said second means to supply a main-charging current again.

7. The improved circuit of claim 6 wherein said main current path has a current-limiting device therein.

8. The improved circuit of claim 6 wherein said fifth means effects a reduction of said main-charging current to substantially zero in response to a voltage of selected magnitude at said third terminal.

9. The impRoved circuit of claim 6 wherein said fifth means have delay means to prevent reduction of said main-charging current until said voltage exceeds said selected magnitude for a selected time.

10. The improved charging circuit of claim 6 wherein said fifth means effects reduction of said main-charging current to substantially zero in response to a voltage of selected magnitude at said third terminal, and wherein said fifth means have delay means to prevent said reduction of main-charging current until said voltage exceeds said selected magnitude before a selected time.

11. An improved battery-charging circuit comprising:

a. first and second terminals for connection to a charging source;

b. third and fourth terminals for connection to a battery to be charged;

c. first means connecting said second and fourth terminals;

d. a first current-control device having a current path and a control terminal;

e. means connecting said current path of said first device between said first and third terminals;

f. bias means connected between said control terminal of said first device and said first terminal;

g. a trickle-charging impedance connected between said first and third terminals;

h. a second current-control device having a current path and a control terminal;

i. means connecting said current path of said second device between said control terminal of said first device and said first means;

j. a voltage-reference circuit connected between said second and fourth terminals;

k. means connecting said control terminal of said second device to a selected point on said voltage reference circuit;

l. a third current control device having a current path and a control terminal;

m. means connecting said current path of said third device between a selected point on said voltage-reference circuit and said first means to shunt the voltage applied to said control terminal of said second device;

n. and means connecting said control terminal of said third device to a selected point on said voltage-reference circuit.

12. The improved battery-charging circuit of claim 11 and further comprising a capacitor connected to said voltage-reference circuit for shunting the voltage applied to said control terminal of said second device.

13. The improved battery charging circuit of claim 11 and further comprising regenerative means connected between said first terminal and said control terminal of said second device.