CN2105791U - Electronic charger - Google Patents

Abstract

The utility model discloses an electronic charger. Which is a double-limit controlled full-automatic charger. The voltage signal of a battery is compared with the reference voltage through a comparator after being divided voltage through a potentiometer, the output signal of the comparator controls a switch circuit. The electronic charger is characterized in that a battery voltage lower limit control circuit is arranged, that is the voltage signal of the battery is compared with the reference voltage through another comparator after being divided voltage through another potentiometer, then an R-S trigger controls the switching of the switch circuit. The electronic charger is adapted for the full automatic charge of batteries.

Description

Electronic charger

The utility model relates to a kind of automatic charger of two limit controls, and it can distinguish that rechargeable battery stores electric situation, begins charging automatically or stops charging, changes stored condition over to.

At present, known chargeable battery is carried out boost charge, method has two kinds: 1. constant voltage charge: charge for a long time with constant voltage; 2. constant current charge:, comprise classification constant current charge method with constant current charge.When cell voltage was lower than final voltage, charging reached and stops charging behind the final voltage.But final voltage comprises two parts, i.e. electromotive force and polarizing voltage, stop charging after, polarizing voltage disappears, battery terminal voltage is lower than final voltage, charger then begins charging again, so repeatedly.Like this, to some extent to over-charging of battery, make that the active material on the electrode comes off in the battery, electric liquid is dry, produces inflatable, causes the lost of life, also wastes a large amount of electric energy simultaneously.

The purpose of this utility model provides a kind of full-automatic charger simple in structure, it can not only distinguish that battery stores electric situation, begins or stops charging automatically, and can not have maintenance work for a long time, automatically replenish the energy of self-discharge of battery loss, the battery that wouldn't use is played the maintenance effect.

The purpose of this utility model is achieved in that charger circuit divides charging circuit, switching circuit and control circuit three parts, and its electrical connection is as follows; (1) charging circuit, transformer input termination civil power, in its two groups of output windings, have centre tapped one group, centre cap ground connection, two outputs are connected with two rectifying tube positive electrical respectively, one rectifying tube negative pole is electrically connected with fast, trickle charge selector switch one end, another rectifying tube negative pole is electrically connected with fast, the trickle charge selector switch other end and current-limiting resistance respectively, the current-limiting resistance other end is electrically connected with the switching circuit input, the switching circuit output is electrically connected with control circuit signal output part and anode respectively, battery cathode ground connection.The switching circuit control end is electrically connected with the control circuit control signal output ends.

(2) switching circuit, switching circuit divide three kinds of situations, a. low-voltage, low current charge.NPN transistor, its collector electrode is electrically connected with input, and base stage is electrically connected with output, and emitter, current-limiting resistance and control end are electrically connected.B. high voltage, low current charge.Photoelectrical coupler, its input utmost point is electrically connected with input, and output stage is electrically connected with output.In two controls extremely, positive pole, current-limiting resistance and control end are electrically connected, minus earth.C. large current charge.Relay two contacts are electrically connected with input and output respectively.Control coil one end is electrically connected with control end, other end ground connection.

(3) control circuit: control circuit divides peripheral circuit and telemetry circuit two parts.A. peripheral circuit, another group output winding of transformer, two outputs are electrically connected with two inputs of rectifier bridge respectively, the negative output terminal ground connection of rectifier bridge, positive output end is electrically connected filter capacitor negative pole and the equal ground connection of three terminal regulator base stage with the filter capacitor positive pole and the three terminal regulator input utmost point respectively.The three terminal regulator output stage is electrically connected with current-limiting resistance, and the current-limiting resistance other end is electrically connected with voltage-stabiliser tube negative pole and controller reference voltage input respectively, voltage-stabiliser tube plus earth.Controller reset terminal, reset switch and ground are electrically connected, the binary signal output respectively with red, green light-emitting diode and be electrically connected.B. telemetry circuit, all integrated circuits, power supply input is anodal all is electrically connected the equal ground connection of negative pole with the three terminal regulator output for it.Signal input part is electrically connected with divider resistance.The divider resistance other end is electrically connected with two potentiometers, one end respectively, the equal ground connection of the other end of two potentiometers.One potentiometer sliding end is electrically connected with upper limit comparator negative input end, and another potentiometer sliding end is electrically connected with lower limit comparator positive input terminal.Reference voltage input is electrically connected with upper limit comparator positive input terminal and lower limit comparator negative input end respectively.Upper limit comparator output terminal is electrically connected with NAND gate A input, and the lower limit comparator output terminal is electrically connected with protective resistance, and the protective resistance other end is electrically connected with reset terminal and NAND gate B input respectively.NAND gate A output is electrically connected with another input of NAND gate B, current-limiting resistance one end and inverter input respectively.NAND gate B output is electrically connected (NAND gate A, B constitute the R-S trigger) with another input of NAND gate A, inverter output is electrically connected with control end and another current-limiting resistance respectively, and the other end of two current-limiting resistances is electrically connected with two signal output parts respectively.

The upper and lower limit of charger control, its definition is the upper limit respectively: i.e. battery types, cell number and the pairing final voltage of charge rate; Lower limit: promptly desired volume accounts for the corresponding battery open circuit voltage of percentage (selecting arbitrarily) of rated capacity.Below be all kinds of battery cells upper and lower bound (full capacity) numeric reference tables when 10 hour rates charge.

During charger work, charger state, cell voltage situation, each comparator and NAND gate output level height, inverter output level and switching circuit state see the following form, and battery charges from off-capacity.

The charger state

Cell voltage

Comparator

NAND gate

Inverter

Switching circuit

The upper limit

Lower limit

A

B

Charging

Be lower than lower limit

+

-

-

+

+

Open-minded

Charging

Between upper and lower limit

+

+

-

+

+

Open-minded

Have a power failure

Reach the upper limit

-

+

+

-

-

Disconnect

Store

Between upper and lower limit

+

+

+

-

-

Disconnect

Reset

Between upper and lower limit

+

+

-

+

+

Open-minded

Annotate :+refer to high level ,-refer to low level.

During the charger switch circuit debugging, red light emitting diodes is bright, and indication is charged; When switching circuit disconnected, green LED was bright, and indication is sufficient, and battery is in stored condition.Along with period of storage prolongs, battery capacity reduces because of self discharge, prescribes a time limit when voltage is lower than down, and charger begins charging automatically.Reset switch uses where necessary, can make battery reach sufficient state within a short period of time.Hurry up, the trickle charge selector switch can according to the charging needs select for use.

Owing to adopt such scheme, can avoid fully overcharging, make battery charge convenient, safely, increase the service life, and only increase by a comparator in the control circuit, elements such as two NAND gate and an inverter.

Below in conjunction with drawings and Examples the utility model is further specified.

Fig. 1 is a general assembly schematic diagram of the present utility model.

Fig. 2 is the switching circuit schematic diagram.

Fig. 3 is the telemetry circuit schematic diagram.

Fig. 4 is the embodiment print pattern.

Fig. 5 is the embodiment sectional arrangement drawing.

Fig. 6 is the I-I cutaway view of Fig. 5.

Among the figure, 1. 5. 6. fast, trickle charge selector switch 13. current-limiting resistances 14. on-off circuits 15. batteries 16. reset switches 17. control circuits 18. green light emitting diode 19. Red LED1s 20. Zener diodes 21. divider resistances 22. three terminal regulators 23. filter capacitors 24. rectifier bridges 25. current-limiting resistances 26. switching transistors 27. current-limiting resistances 28. photoelectrical couplers 29. relays 30. potentiometers 31. divider resistances 32. potentiometers 33. upper limit comparators 34. lower limit comparators 35. protective resistances 36. NAND gate A 37. NAND gate B 38. resistance 39. phase inverters 40. resistance 41. wires 42. integrated circuit LM324 43. integrated circuit CD4011 44. spring battery folder 45. insulation crusts 46. power lines 47. printed circuit board (PCB)s of reference voltage input 7. outputs 8. control ends, 9. inputs, 10. commutation diodes, 11. transformers 12. of signal output part (red light) of control output end 2. signal input part 3. reset terminals, 4. signal output parts (green light).

Among Fig. 1, rectifier diode (10) is formed rectification circuit, when fast, trickle charge selector switch (12) are full-wave rectification when closed, promptly fills soon; During unlatching halfwave rectifier, i.e. trickle charge.Transformer in the charging circuit (11) output voltage is higher than the battery voltage limit three ten-day period of hot season.Select 9～15 volts of three terminal regulator (22) output voltages.Charger resetted when reset switch (16) was closed.

Among Fig. 2, battery capacity is less, and charging current when battery voltage limit is lower than the three terminal regulator output voltage, is selected a circuit at the battery more than 0.5 ampere for use; When battery voltage limit is higher than or during near the three terminal regulator output voltage, selects the b circuit for use.For high capacity cell, select the c circuit for use.

Among Fig. 3, adjust potentiometer (30) and make cell voltage reach in limited time sliding end output voltage and reference voltage equivalence; It is down in limited time that adjustment potentiometer (32) makes cell voltage, sliding end output voltage and reference voltage equivalence.NAND gate A(36) and NAND gate B(37) form the R-S trigger.

In embodiment illustrated in fig. 5, charger charges to four AA type ickel-cadmium cells, integrated circuit LM324(42) in two operational amplifiers respectively as the upper and lower limit comparator.Integrated circuit CD4011(43) in, two NAND gate are respectively as NAND gate A and B, and after two NAND gate correspondences extremely were connected in parallel in addition, an input termination positive source as inverter, adopted transistor to make switch element.Circuit board and battery are installed in the insulation crust, and be spaced intermediate.

Claims (5)

1, a kind of electrical charger, battery voltage signal is after the potentiometer dividing potential drop, compare by comparator and reference voltage, comparator output signal control switch circuit, it is characterized in that: other establishes cell voltage lower limit control circuit, be that battery voltage signal is after another potentiometer dividing potential drop, compare by another comparator and reference voltage, comparative result and The above results are imported the R-S trigger of being made up of two NAND gate simultaneously, the trigger output signal is after anti-phase, the Kai Heguan of control switch circuit, promptly charger charges and does not charge, and uses red respectively, green light-emitting diode indication.

2, charger according to claim 1 is characterized in that: adopt transistor as switch element.

3, charger according to claim 1 is characterized in that: adopt photoelectrical coupler as switch element.

4, charger according to claim 1 is characterized in that: adopt relay as switch element.

5, charger according to claim 1 is characterized in that: between R-S trigger one output and ground reset switch is set.

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