High-speed battery charging device and a control circuit therefor

• US 5,241,258 A
• Filed: 04/22/1992
• Issued: 08/31/1993
• Est. Priority Date: 11/01/1991
• Status: Expired due to Term

• Current Assignee: Jingpin Technologies, LLC (Intellectual Ventures LLC)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Cheon, Kyeongyong
• Primary Examiner(s): KINCAID, KRISTINE LYNN
• Application Number:
  US07/871,811
• Time in Patent Office: 496 Days
• Field of Search: 320/20, 320/21, 320/22, 320/23, 320/24, 320/31, 320/32, 320/40, 320/39
• US Class Current: 320/137
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors
• CPC Class Codes: Y10S 320/12 Precharging analysis, e.g. determining presence of battery
• CPC Class Codes: Y10S 320/21 State of charge of battery
• CPC Class Codes: Y10S 320/31 Plural rectifier systems

Abstract

A battery charging device providing both a rapid high charging rate and a trickle rate for a substantially fully charged battery and employing first, second and third rectifying circuits for rectifying an AC current into a DC current; a charging state switch circuit for outputting information about the charging-state switching of the battery between a high charging rate and a trickle charge rate; charging driving circuits for outputting a driving signal representing high speed charging or trickle charging in accordance with the output of the charging state switch circuit; a charging circuit for performing high speed charging or trickle charging in response to the driving signal; an auxiliary controlling circuit for controlling the battery to be charged with a regulating current during a rapid high charging rate; a battery mounting sensing circuit for sensing the mounting of a battery to be charged; a charging state indicating circuit for indicating a rapid high charging rate of the battery mounting sensing circuit and the charging driving circuit; and a relay controlling circuit for controlling the driving of a relay in the auxiliary controlling circuit.

Claims

1. A battery charging device having a control circuit, for high-speed charging at low battery voltage, and for trickle charging where a battery is fully charged, in a charging circuit of the battery, and comprising:

first, second and third rectifying means for rectifying an AC current into a DC current;

charging state switching means for outputting information about the switching of the battery between high-speed charging and trickle charging;

charging circuit driving means for outputting a driving signal representing the high speed charging or the trickle charging in accordance with the output of said charging state switch means;

charging circuit means for performing the high speed charging or the trickle charging in response to said driving signal;

auxiliary controlling means for controlling the battery to be charged with a regulating current during the high-speed charging;

battery mounting sensing means for sensing the mounting of the battery to be charged;

charging state indicating means for indicating the rate of the high speed charging of the battery; and

relay controlling means for controlling the driving of a relay and responsive to said auxiliary controlling means.

2. A battery charging device as claimed in claim 1, wherein said first rectifying means includes a rectifier diode;

and said charging circuit means includes first and second resistors with a common terminal thereof connected to the cathode of said rectifier diode of said first rectifying means;

said charging circuit means further including a first transistor with a base terminal connected to the other terminal of said first resistor and with a collector terminal connected to the other terminal of said second resistor;

an FET with a gate terminal connected to the emitter of said first transistor and a drain terminal;

said second rectifying means including a rectifying diode having a cathode connected to said drain terminal of said FET;

said charging circuit means further including a third resistor having one terminal connected to the base terminal of said first transistor;

a second transistor having a collector terminal connected to the drain terminal of said FET and a base terminal connected to the other terminal of said third resistor;

said charging circuit means further including a third transistor having a base terminal connected to the emitter terminal of said second transistor and with an emitter terminal connected to the source terminal of the FET; and

a fourth resistor connected between the base and the emitter terminals of the third transistor.

3. A battery charging device as claimed in claim 2, wherein said battery mounting sensing means comprises:

a fifth resistor having one terminal connected to the emitter terminal of said third transistor, a sixth resistor with a terminal connected to the other terminal of said fifth resistor and the other terminal of said sixth resistor connected to ground;

a shunt regulator having a shunt terminal connected to the common terminal of said fifth and sixth resistors and with an anode connected to ground; and

a capacitor connected across the cathode and said shunt terminal of said shunt regulator.

4. A battery charging device as claimed in claim 3, wherein said charging state indicating means comprises:

a zener diode with a cathode thereof connected to the cathode of the shunt regulator;

a seventh resistor with one terminal connected to the anode of the zener diode;

an eight resistor with one terminal connected to the cathode of a rectifying diode of the third rectifying means;

a diode with an anode connected to the other terminal of said eighth resistor;

a fourth transistor having a collector terminal thereof connected to the anode of said diode, a ninth resistor connected between the base of said fourth transistor and the cathode of said zener diode; and

a light emitting diode with the anode thereof connected to the emitter terminal of said fourth transistor, and with the cathode thereof connected to ground.

5. A battery charging device as claimed in claim 4, wherein said charging circuit driving means comprises:

ninth, tenth and eleventh resistors connected in series and the common terminal of said tenth and eleventh resistors connected to the cathode of the zener diode of said first rectifying means;

said device further comprising a voltage comparator with an inverting terminal thereof connected to the common terminal of said ninth and tenth resistors and a non-inverting terminal connected to the other terminal of said ninth resistor; and

the other terminal of said eleventh resistor connected to ground.

6. A battery charging device as claimed in claim 5, wherein said auxiliary controlling means comprises:

a second comparator having an inverting and non-inverting terminal, twelfth and thirteen resistors and fourteenth and fifteenth resistors, respectively connected in series, the common terminal of said twelfth and thirteenth resistors being connected to the emitter of said third transistor, the common terminal of said fourteenth and fifteenth resistors being connected to said non-inverting terminal and the other terminal of said twelfth resistor connected to said inverting terminal;

the other terminal of said fourteenth resistor being connected to the other terminal of said thirteenth resistor;

a sixteenth resistor connected between said inverting terminal and ground and the other terminal of said fifteenth resistor being connected to ground.

7. A battery charging device as claimed in claim 6, wherein said relay controlling section comprises:

seventeenth and eighteenth resistors connected in series;

a fifth transistor having an emitter and base terminal respectively connected to the other respective terminal of said seventeenth and eighteenth resistors and an anode connected to ground;

a capacitor connected between the cathode and shunt terminal of said regulator;

a sixth transistor having an emitter providing an output signal;

a nineteenth resistor connected between the base and collector of said sixth transistor, said collector being connected to ground;

twentieth and twenty first resistors being connected in series and the common terminal thereof being connected to said shunt terminal.

8. The battery charging device as claimed in claim 7, wherein said charging state switching means comprises:

a contact type relay with a make-before-break (MBB) contact input terminal thereof connected to the common terminal of said thirteenth and fourteenth resistors and a coil input terminal thereof connected to the cathode of said rectifying diode in said third rectifying means;

a second FET having (1) a drain terminal connected to the coil output terminal of said MBB contact type relay, (2) a gate terminal connected to the non-inverting terminal of said second voltage comparator and (3) a source terminal connected to ground;

a third FET having (1) a gate terminal connected to a charging state sensing signal line, (2) a source electrode connected to ground;

a twenty second resistor and a twenty third resistor connected to the gate electrode of said second FET, the respective other terminal of said twenty second and twenty third resistors being connected respectively to ground and to the drain gate of said third FET and a second diode connected across the input and output terminals of said coil.