CN102148524B

CN102148524B - Charger

Info

Publication number: CN102148524B
Application number: CN201010114917.6A
Authority: CN
Inventors: 田角峰
Original assignee: Positec Power Tools Suzhou Co Ltd
Current assignee: Positec Power Tools Suzhou Co Ltd
Priority date: 2010-02-05
Filing date: 2010-02-05
Publication date: 2014-12-17
Anticipated expiration: 2030-02-05
Also published as: CN102148524A

Abstract

The invention provides a charger, comprising a charging circuit for charging a battery by utilizing an external power source, a controller for controlling the operation of the charger, a manual switch which can be closed or disconnected through the operation so as to control the power-on or power-off of the charging circuit, and an electronic switch connected with the manual switch in parallel, wherein the controller can be used for closing or disconnecting the electronic switch; and when the manual switch is closed, the external power source is capable of supplying power to the controller, and the controller is used for closing the electronic switch. Compared with the prior art, the technical scheme provided by the invention has the advantages that the battery can be charged under a condition that the battery is completely discharged; the requirements of users can be met and unnecessary waste can be avoided.

Description

Charging device

Technical Field

The present invention relates to a charger, and more particularly, to a charger capable of charging a battery when the battery is completely discharged.

Background

With the development of technology, the variety of batteries is increasing, and rechargeable batteries, such as nickel-cadmium batteries, lead-acid batteries, lithium batteries, and the like, are developed to meet the needs of different users. However, the service life of the rechargeable battery is limited, and the quality of the charger has a great influence on the service life of the rechargeable battery because the rechargeable battery is often charged by using the charger.

Most of the existing chargers supply power to a controller of the charger by a battery when the battery is connected into the charger, so that the charger performs various judgment works, and when commercial power is input, the commercial power is used for supplying power to the controller. Because the existing charger mostly adopts an electronic switch to control the on-off of the charger and the commercial power, the electronic switch can be closed only when the battery has certain electric energy, and the controller can do various complex operations. If the battery is completely discharged or the remaining power is not large when the battery is connected to the charger, the battery may not provide enough power to close the electronic switch, and in this case, the charger may not charge the battery, so that the battery that may be used continuously may have to be discarded, which wastes resources.

Disclosure of Invention

The invention provides a charger which can still charge a battery when the electric quantity of the battery is too low.

In order to achieve the purpose, the technical scheme of the invention is as follows: a charger, comprising: a charging circuit for charging the battery by using an external power supply; a controller for controlling the operation of the charger; the manual switch can be operated to be switched on or switched off so as to control the charging circuit to be powered on or powered off; an electronic switch connected in parallel with the manual switch; the controller can control the electronic switch to be switched on or switched off, when the manual switch is switched off, the external power supply can supply power to the controller, and the controller can control the electronic switch to be switched on or switched off.

Preferably, the charger has an external power supply circuit connected to the controller, and when the manual switch or the electronic switch is turned off, the external power supply circuit can supply power to the controller by using electric energy of the external power supply.

Preferably, the external power supply circuit is provided with a DC/DC conversion circuit.

Preferably, the external power supply is an alternating current power supply, the charger has an AC/DC conversion circuit for converting alternating current of the external power supply into direct current, and the current flowing into the power supply circuit of the external power supply is the direct current.

Preferably, the manual switch is a non-self-locking mechanical switch.

Preferably, the electronic switch is a relay.

Preferably, the relay is provided with a coil and a triode, and the controller controls the conduction or the blocking of the triode to control whether the coil is electrified or not.

Preferably, the source of the electrical energy flowing through the coil is the external power supply.

Preferably, when the manual switch is pressed, the charger immediately charges the battery.

Compared with the prior art, the charger is provided with the manual switch and the electronic switch, the manual switch is connected with the electronic switch in parallel, when the manual switch is closed, the external power supply can supply power to the controller, and the controller can control the electronic switch to be closed. Through the scheme, the battery can be charged by utilizing the external power supply when the battery is completely discharged or the electric quantity is extremely low, so that the requirement of a user is met, and unnecessary waste of the battery is avoided.

Drawings

The invention is further described with reference to the following figures and embodiments.

FIG. 1 is a schematic diagram of the operating state of a charger;

FIG. 2 is a block diagram of a charging circuit of the charger of FIG. 1;

FIG. 3 is a circuit diagram of the charging circuit of the charger of FIG. 1;

fig. 4 is a flowchart of the operation of the charger of fig. 1.

Wherein,

100. charger 61, battery voltage detection module 76, connection point

10. External power supply 62, charging voltage detection module 77, connection point

20. Battery 63, clock circuit 78, current input line

30. Switch assembly 64, indicator block 79, connection point

31. Manual switch 65, charging current detection module 80, main power supply line

32. Electronic switch 70, controller power supply module R1, R2 resistance

40. External power supply detection module 71, first power supply circuit R3, R4 resistor

41. Light emitting unit 72, second power supply circuits R5, R6. resistors

42. Receiver 73, third supply circuit R7, R8. resistor

50. Conversion module 74 controlled parts R9, R10 resistance

60. Controller 75, current stabilizing module R11, R12 resistance

R13, R14, resistor D3, D4., diode C1, C2. capacitance

R15, R16, resistor D5, D9., diode C3, C4, capacitor

Q1. triode D6, D7. LED Z1. stabilivolt

Q2, Q3.MOS tube D8. LED

D1, D2. diode KM. coil

Detailed Description

Referring to fig. 1, a working state of a charger 100 according to a first embodiment of the present invention is schematically shown. The charger 100 may charge the battery 20 using the external power source 10.

The external power source 10 may be an ac power source or a dc power source, and the power source may be electric power generated by commercial power or other commercial or civil power generators.

The battery 20 is a rechargeable battery such as: nickel-cadmium batteries, lithium batteries, lead-acid batteries, nickel-hydrogen batteries, and the like, and in the present embodiment, it is a lead-acid battery.

It is to be understood that the battery 20 is not limited to a single battery in a general sense, and includes a battery pack having a plurality of batteries.

Please refer to fig. 2, which is a schematic block diagram of a charging circuit of the charger 100. The charging circuit of the charger 100 has a main power supply line 80 connected to the external power source 10 and the battery 20, and the main power supply line 80 has a switch assembly 30, an external power source detection module 40, a conversion module 50, a controller 60 and a controller power supply module 70. The switch assembly 30 controls the connection of the charger 100 and the external power supply 10, and the external power supply detection module 40 is connected to the switch assembly 30, detects whether the external power supply 10 is input, and can send detection information to the controller 60. The conversion module 50 can convert the voltage inputted from the external power source 10 into a voltage suitable for the operation of the charger 100. The controller 60 controls the charger 100 to charge the battery 20, and has a sleep state and an operation state. The controller power supply module 70 obtains the electric energy of the external power source 10 or the battery 20 to supply power to the controller 60, and meets the power consumption requirements of different sleep states and working states.

Fig. 3 is a circuit diagram of a charging circuit of the charger 100. The switch assembly 30 is disposed near the position where the main power supply line 80 is connected to the external power source 10, and includes a manual switch 31 and an electronic switch 32 connected in parallel.

The manual switch 31 is a non-self-locking mechanical switch, when the manual switch 31 is pressed, the connected circuit is conducted, and when the applied external force is removed, the manual switch 31 is automatically disconnected.

The electronic switch 32 may be a relay, a triode, a thyristor, a solid-state relay, or other controllable electronic components with on/off function, and in this embodiment, it is a relay. The relay mainly comprises a coil KM, a triode Q1, a resistor R11 and a resistor R12. The transistor Q1 is an NPN-type transistor serving as a switching element for switching the coil KM on and off, and its base is connected to the controller 60 through a resistor R11. Resistor R12 is connected in parallel with the base and emitter of transistor Q1. The coil KM is electrically connected to the collector of the transistor Q1 and to the controller power supply module 70.

When the controller 60 controls the electronic switch 32 to be closed, a high level is provided for the base electrode of the triode Q1, so that the triode Q1 is conducted, the coil KM is electrified to generate magnetic force, the relay is attracted, and the circuit connected with the relay is conducted. When the high level is removed by controller 60, transistor Q1 will block the circuit, and coil KM will stop energizing, and the relay will disconnect the circuit.

The external power detection module 40 is used for detecting whether the power of the external power supply 10 is input, is connected to the switch assembly 30 and the controller 60, and is capable of sending a detection signal to the controller 60. The external power detection module 40 may be a sampling circuit, an optical coupler power detection circuit, or a detection circuit composed of a plurality of resistors, and in this embodiment, it is an optical coupler power detection circuit. The external power detection module 40 includes a light emitting portion 41 and a receiving portion 42, the light emitting portion 41 includes a light emitting diode D8 and a diode D9 which are connected in parallel and in opposite directions, and is connected to the switch assembly 30 through a resistor R13, and when the switch assembly 30 is turned on and the external power source 10 inputs power, the light emitting portion 41 emits light. The receiving portion 42 is a photo transistor, which receives the light and conducts to send a detection signal to the controller 60.

The conversion module 50 is disposed in the main power supply line 80, and converts the voltage input by the external power supply 10 through the main power supply line 80, so as to be suitable for charging the battery 20. The conversion module 50 may be an AC/DC conversion circuit, may also be a DC/DC conversion circuit, and may also have both an AC/DC conversion circuit and a DC/DC conversion circuit.

It is understood that the conversion module 50 may also be configured to perform constant current charging and constant voltage charging of the battery 20, which will not be described in detail herein due to the space limitation and the well-known technology in the art.

The controller power supply module 70 includes a first power supply circuit 71, a second power supply circuit 72, and a third power supply circuit 73. When the external power supply 10 is not input, the first power supply circuit 71 can obtain the electric energy of the battery 20 to supply power to the controller 60 under the control of the controller 60, the second power supply circuit 72 directly obtains the electric energy of the battery 20 to supply power to the controller 60, and the third power supply circuit 73 cannot supply power to the controller 60; when the external power source 10 is input, the controller 60 only has the external power source 10 as the power source.

The first power supply circuit 71 and the second power supply circuit 72 have the same current input line 78, and the current input line 78 is electrically connected to the main power supply line 80 to form a connection point 79, and the connection point 79 is located at a position of the main power supply line 80 close to the battery 20, and a diode D1 is disposed between the connection point 79 and the conversion module 50 to prevent the current of the battery 20 from flowing into the conversion module 50.

The first power supply circuit 71 mainly includes a controlled module 74 and a voltage regulator module 75. The controlled module 74 is configured to receive control of the controller 60, so that the first power supply circuit 71 has two states, namely, an energized state and a non-energized state, and further, whether the first power supply circuit 71 supplies power to the controller 60 is controlled.

The controlled module 74 includes a resistor R4, a MOS transistor Q3, a capacitor C1, a resistor R2, a resistor R1, and a MOS transistor Q2. The MOS transistor Q3 is connected with the capacitor C1 in parallel and then connected with the grid of the MOS transistor Q2, the grid of the MOS transistor Q3 is connected with the controller 60 through the resistor R4, and the resistor R1 is connected with the source and the grid of the MOS transistor in parallel. At the moment when the battery 20 is connected to the charger 100, since the capacitor C1 is charged as a short circuit, the current can flow through the resistor R1 to provide a turn-on voltage for the MOS transistor Q2, so that the MOS transistor Q2 is turned on, the first power supply circuit 71 is in a powered state, and the current enters the controller 60 through the voltage stabilizing module 75, at this time, the controller 60 provides a voltage to the gate of the MOS transistor Q3 to turn on, so as to maintain the powered state of the first power supply circuit 71. When the first power supply circuit 71 needs to enter the non-powered state, the controller 60 stops supplying the voltage to the MOS transistor Q3, the controlled module 74 no longer forms a path, the gate of the MOS transistor Q2 no longer has a voltage input, the current cannot pass through the MOS transistor Q3, and the first power supply circuit 71 is in the non-powered state.

It is understood that the MOS transistors Q2, Q3 may be replaced by other electronic components with circuit on/off control, such as transistors, relays, etc., which are not specifically illustrated but are covered by the scope of the present invention as long as the functions and effects achieved by the MOS transistors Q2, Q3 are the same or similar to the present invention.

The voltage stabilizing module 75 is a DC/DC conversion circuit that converts the voltage of the first power supply circuit 71 into a DC voltage suitable for the controller 60 and supplies the DC voltage to the controller 60. When the external power source 10 is not input, the first power supply circuit 71 obtains the electric energy of the battery 20 to supply power to the controller 60, and the voltage stabilizing module 75 reduces the voltage input by the battery 20 to be suitable for the controller 60, and can continuously and stably maintain the output of the voltage. In the present embodiment, if the voltage of the battery 20 is 28V and is continuously decreased, and the operating voltage of the controller 60 is 5V, the voltage stabilizing module 75 decreases the voltage provided by the battery 20 to 5V, and then provides the voltage to the controller 60. When the external power source 10 is input, since the voltage of the dc power converted and output by the conversion module 50 may be too high, if the controller 60 is directly powered, the controller 60 may be burnt, and at this time, the voltage stabilizing module 75 may reduce the voltage of the current output by the conversion module 50 and make the current more stable, so as to be suitable for supplying power to the controller 60.

Only one resistor R10 is provided in the second power supply circuit 72, and the load carrying capacity of the second power supply circuit 72 is smaller than that of the first power supply circuit 71, i.e., the first power supply circuit 71 is able to drive more circuit elements. The resistor R10 can be set to 1M, 1.5M, 2M, etc., and in this embodiment, its resistance is 1M. The second power supply circuit 72 and the first power supply circuit 71 have a connection point 76, and the two are connected to a power input terminal of the controller 60. The connection point 76 is located between the regulator module 75 and the controller 60, and in order to prevent current from flowing to the regulator module 75 when the first power supply circuit 71 is in the non-energized state, a diode D5 is provided between the connection point 76 and the regulator module 75.

When the controller 60 is powered by only the second power supply circuit 72, since the power supply current is small and not stable enough, the controller 60 does not perform data comparison or judgment, and can enter and maintain the sleep state, and when the controller is awakened, the controlled module 74 can be controlled to enable the first power supply circuit 71 to enter the power-on state, so as to control the electronic switch 32 to be closed.

It can be understood that, in order to make the second power supply circuit 72 supply power to the controller 60 more stably and prevent the controller 60 from being burnt out due to the overhigh instantaneous voltage in the second circuit, a voltage regulator tube Z1 may be connected at the connection point 76, at this time, the second power supply circuit 72 supplies power to the controller 60 through the resistor R10 and the voltage regulator tube Z1 in series, because the resistor R10 prevents the voltage from being large and generates a large voltage drop, the operating voltage of the voltage regulator tube Z1 is smaller than the rated voltage thereof, so that the current flowing to the controller 60 is small and stable. In addition, the second power supply circuit 72 is provided with a capacitor C2 in parallel with the voltage regulator tube Z1, so that the requirement of sudden increase of the electric energy requirement in a short time when the controller 60 is awakened from the sleep state is met, and the controller 60 is prevented from being halted due to insufficient power supply.

The third power supply circuit 73 is capable of supplying power to the controller 60 by using the power of the external power source 10, and is directly connected to the main power supply line 80, and the connection point is located at a portion after the external power is converted into the dc power by the conversion module 50.

In order to optimize the circuit, the third power supply circuit 73 and the first power supply circuit 71 may share one voltage stabilizing module 75, that is, the first power supply circuit 71 is connected to the third power supply circuit 73 and then connected to the voltage stabilizing module 75, so as to form a connection point 77, and a diode D3 is disposed at a position of the first power supply circuit 71 close to the connection point 77, and a diode D2 is disposed at a position of the third power supply circuit 73 close to the connection point 77, so as to limit the direction of the current, and prevent the current of the third power supply circuit 73 from flowing into the first power supply circuit 71, or the current of the first power supply circuit 71 from flowing into the third power supply circuit 73. To prevent the voltage regulator module 75 from being burned out by excessive current in the circuit at the instant of circuit connection, a resistor R9 may be provided between the connection point 77 and the voltage regulator module 75 to protect the voltage regulator module 75.

It is understood that the conversion module 50 may have two positive output terminals, and the output voltages of the two output terminals are different, one is suitable for charging the battery 20, and the other is suitable for supplying power to the controller 60, and the third power supply circuit 73 is directly connected to the output terminal of the conversion module 50 for supplying power to the controller 60, so that the third power supply circuit 73 may not be connected to the voltage stabilizing module 75, and directly supplies power to the controller 60.

It will be appreciated that the connection point of the coil KM of the electronic switch 32 to the controller power supply module 70 is located between the voltage regulator module 75 and the diode D5.

The first power supply circuit 71, the second power supply circuit 72 and the third power supply circuit 73 supply power to the controller 60 as shown in the following table one.

Watch 1

When no external power source 10 and no battery 20 are connected to the charger 100 as in serial No. 1, the charger 100 does not perform any operation; if serial numbers 2 and 3 indicate that the external power source 10 is connected and the battery 20 is not available, the controller 60 does not control to turn on the electronic switch 32, and at this time, the manual switch 31 is turned on to supply power to the controller 60 through the third power supply circuit 73, but the controller 60 does not operate because the battery 20 is not found.

As shown in serial numbers 4, 5, 6, 7 and 8, when the external power supply 10 is not connected and the battery 20 is installed in the charger 100, the first power supply circuit 71 and the second power supply circuit 72 both supply power to the controller 60 (e.g. serial number 4), and the supply current of the first power supply circuit 71 is greater than the supply current of the second power supply circuit 72, the controller 60 determines whether the battery 20 needs to be charged, when charging is not needed, the controller 60 does not control the electronic switch 32 to be turned on, when the battery 20 needs to be charged (e.g. serial number 5), the controller 60 controls the electronic switch 32 to be turned on, and detects whether the input of the external power supply 10 exists through the external power supply detection module 40, at this time, if the input of the external power supply 10 is not found, the controller 60 turns off the first power supply circuit 71 (e.g. serial number 6), and turns off the electronic switch 32, and only the second power. The controller 60 turns on the first power supply circuit 71 once every interval and controls the electronic switch 32 to turn on once (e.g., serial No. 7), so as to determine whether the external power source 10 is input.

As shown in the serial number 8, when the input of the external power source 10 is detected, the electronic switch 32 is controlled to be turned on, and the charger 100 is controlled to start charging the battery 20, at which time the third power supply circuit 73 is turned on and supplies power to the controller 60. Due to the length of the line, the voltage of the third power supply circuit 73 at the connection point 77 is higher than the voltage of the first power supply circuit 71, and therefore, the first power supply circuit 71 does not supply power to the controller 60 any more after the third power supply circuit 73 is turned on.

As shown in the serial number 9, when the battery 20 is fully charged, the controller 60 controls the electronic switch 32 to be turned off, and at this time, the controller 60 is only powered by the second power supply circuit 72, so that the charger 100 does not consume the power of the external power supply 10, and because the power supply current of the second power supply circuit 72 is small, the power consumed by the battery 20 is very small, thereby achieving the purpose that the whole charger 100 saves power very much.

As shown in the serial number 10, after the battery 20 is fully charged, the controller 60 controls the first power supply circuit 71 to be turned on once every certain time interval, at this time, the controller 60 determines whether the battery 20 needs to be charged, and repeats the above functions if necessary, and controls the first power supply circuit 71 to stop supplying power if not necessary.

As shown in serial numbers 11 and 12, when the external power source 10 and the battery 20 are both connected to the charger 100, and the controller 60 does not charge the battery 20 accordingly, if the manual switch 31 is turned on, the charger 100 immediately starts to charge the battery 20 (as shown by serial number 11), and controls the electronic switch 32 to be turned on (as shown by serial number 12), thereby implementing the function of quick response charging.

If the battery 20 is loaded into the charger 100 and is over-discharged or even completely discharged, it may not have enough power to complete the functions of serial nos. 7 and 8, that is, the controller 60 cannot provide enough power to turn on the electronic switch 32, at this time, if the manual switch 31 is not closed, the charger 100 cannot start charging the battery 20, if the manual switch 31 is closed, the external power source 10 supplies power to the controller 60 through the third power supply circuit 73, so that the controller 60 can control to turn on the electronic switch 32, and even if the manual switch 31 is turned off at this time, the power enters the third power supply circuit 73 from the electronic switch 32, so as to ensure that the controller 60 is powered, and thus, the whole charger 100 can charge the battery 20.

It is understood that a button battery may be separately provided to provide the controller 60 with the power in the sleep state, and the controller 60 may be enabled to switch on the first power supply circuit 71, so that the second power supply circuit 72 may be omitted.

The controller 60 is used for controlling the charger 100 to charge the battery 20, and is connected with a battery voltage detection module 61, a charging voltage detection module 62, a clock circuit 63, an indication module 64 and a charging current detection module 65. A watchdog circuit is also integrated within the controller 60 for waking up the controller 60 when the controller 60 enters a sleep state.

The battery voltage detection module 61 is connected to the controller power supply module 70, and detects the voltage of the battery 20 after the battery 20 is connected to the charger 100, and feeds back the detection information to the controller 60, and the controller 60 performs calculation to obtain the voltage value of the battery 20.

The charging voltage detection module 62 is configured to detect a charging voltage during the charging process of the battery 20 by the charger 100, feed back detection information to the controller 60, and obtain the charging voltage through calculation by the controller 60.

Clock circuit 63 is used to provide a clock source to controller 60 and is capable of drawing power from controller 60 to maintain operation of clock circuit 63.

It is understood that the clock circuit 63 is an external low frequency clock circuit, and when the controller 60 enters the sleep mode, the power supply to the clock circuit 63 is stopped, thereby saving power.

The indication module 64 includes a plurality of light emitting diodes that emit light or change a light emitting color under the control of the controller 60, and the change in the light emitting color may be used to indicate the operating state of the charger 100 or whether the battery 20 has been fully charged. In this embodiment, two light emitting diodes D6 and D7 are provided to emit light of two colors of red and green, respectively. The status of the LED, corresponding to the status of the charger, is shown in table two below.

Watch two

Controller 60 draws power from controller power module 70, can send control signals to electronic switch 32 and controller power module 70, and can provide power to clock circuit 63 and indicator module 64.

It can be understood that, when the controller 60 determines whether there is an input of the external power supply 10 according to the detection signal sent by the external power supply detection module 40, the determination manner may be different due to different specific compositions of the external power supply detection module 40, for example, the external power supply detection module 40 may be a sampling circuit, that is, it obtains the electric energy of the battery 20 to work, and performs sampling detection on the input of the external power supply 10, when the input of the external power supply 10 is not detected, it outputs a low level to the controller 60, and when the input of the external power supply 10 is detected, it outputs a high level to the controller 60, and with respect to the controller 60, the low level or the high level output by the external power supply detection module 40 is the detection signal. In this embodiment, the external power detection module 40 is an optical coupler power detection circuit, when the external power 10 is input, the detection signal output by the external power detection module 40 is an electrical signal, when the external power 10 is not input, the detection signal output by the external power detection module 40 is a null value, that is, the detection signal does not send an electrical signal, and the controller 60 determines whether the external power 10 is input according to the received electrical signal or the null value. Of course, the technical solution of the controller 60 determining whether the external power supply 10 is input through the external power supply detection module 40 is not limited thereto, and is not exhaustive again because of being limited to space, but the technical solution and the effect achieved by the technical solution are the same as or similar to the present invention, and are all covered by the scope of the present invention.

Referring to fig. 4, a flowchart of the operation of the controller 60 controlling the charger 100 to charge the battery 20 is shown.

When the battery 20 is installed in the charger 100, the first power supply circuit 71 and the second power supply circuit 72 both obtain power from the battery 20 to supply power to the controller 60, and the controller 60 starts to operate, and maintains the first power supply circuit 71 in the power-on state, and calculates the voltage of the battery 20 through the detection data provided by the battery voltage detection module 61, and determines whether the battery needs to be charged by comparing with a preset voltage value inside the controller 60, in this embodiment, for example, the preset voltage value is 26V, when the controller 60 finds that the voltage of the battery 20 is greater than 26V, it is considered that the battery 20 does not need to be charged, and when the controller 60 finds that the voltage of the battery 20 is less than or equal to 26V, it is considered that the battery 20 needs to be charged.

When the battery 20 does not need to be charged, the controller 60 controls the first power supply circuit 71 to enter a non-charging state, which is powered only by the second power supply circuit 72, the charging process is finished, and the controller enters a sleep state; when the battery 20 is detected to need to be charged, the controller 60 controls the electronic switch 32 to be closed, and the external power supply detection module 40 is used for detecting whether the external power supply 10 is input or not, when the external power supply 10 is not found, the controller 60 controls the first power supply circuit 71 to enter an unpowered state, the first power supply circuit is only powered by the second power supply circuit 72, at the moment, the controller 60 enters a dormant state, and is awakened once by a watchdog circuit in the controller at intervals, after the first power supply circuit is awakened, the controller is switched on the first power supply circuit 71 and immediately controls the electronic switch 32 to be closed once, the external power supply detection circuit 40 is used for detecting whether the external power supply 10 is input or not, when the external power supply 10 is not input, the controller enters the dormant state again, and the steps of awakening; when the input of the external power source 10 is detected, the battery 20 starts to be charged.

It will be appreciated that the controller 60 is awakened from the sleep mode at intervals which may be gradually extended, such as every 3 seconds for the first 5 minutes, and the electronic switch 32 is controlled to close to detect the presence of the external power source 10, and if the external power source 10 is not present, then the controller 60 is awakened at intervals of 30 seconds from the 6 th minute to the 10 th minute, and then at intervals of 10 minutes. Of course, the invention is not limited to the rules of the wake-up controller 60 described in the present embodiment, and other modifications may be made by those skilled in the art, which are within the scope of the invention as long as their technical spirit is the same as or similar to the present invention.

During the charging process, the controller 60 determines whether the battery 20 is fully charged by acquiring the data detected by the battery voltage detection module 61, the charging voltage detection module 62 and the charging current detection module 65, and may also determine whether the battery 20 is fully charged according to only one of the data of the battery voltage, the charging voltage or the charging current. In the embodiment, for example, to judge whether the battery 20 is fully charged only according to the charging current, a preset current value, for example, 300mA is set in the controller 60, and when the controller 60 calculates the data detected by the charging current detection module 65, and the obtained current value is greater than 300mA, it is determined that the battery 20 is not fully charged, and the charging needs to be continued; when the obtained current value is less than or equal to 300mA, the controller 60 determines that the battery 20 is fully charged, and controls the electronic switch 32 to be turned off, thereby ending the charging process.

It will be appreciated that when the battery 20 is fully charged, if not disconnected from the charger 100, the charger 100 will enter a sleep state, powered only by the second power supply circuit 72, after which the controller 60 will wake up once every interval, switch on the first power supply circuit 71 and detect the battery voltage, if the controller 60 finds that the battery 20 needs to be charged, it will control the charger 100 to charge the battery 20, if the battery 20 does not need to be charged, it will control the first power supply circuit 71 not to be powered, and then enter the sleep state again.

It will be appreciated by those skilled in the art that the invention can be implemented in other ways, provided that the technical spirit of the invention is the same as or similar to the invention, or that any changes and substitutions based on the invention are within the protection scope of the invention.

Claims

1. A charger, comprising:

a charging circuit for charging the battery by using an external power supply;

a controller for controlling the operation of the charger;

the manual switch can be operated to be switched on or switched off so as to control the charging circuit to be powered on or powered off; the electronic switch is connected with the manual switch in parallel, and the on or off of the electronic switch can control the charging circuit to be powered on or powered off;

the method is characterized in that: the controller can control the electronic switch to be switched on or switched off; the battery can supply power to the controller, and the controller can control the electronic switch to be closed when the battery needs to be charged; when the manual switch is closed, the external power supply can supply power to the controller, and the controller can control the electronic switch to be closed.

2. The charger of claim 1, wherein: the charger is provided with an external power supply circuit connected with the controller, and when the manual switch or the electronic switch is turned off, the external power supply circuit can supply power to the controller by using the electric energy of the external power supply.

3. The charger of claim 2, wherein: the external power supply circuit is provided with a DC/DC conversion circuit.

4. The charger of claim 3, wherein: the external power supply is an alternating current power supply, the charger is provided with an AC/DC conversion circuit, alternating current of the external power supply is converted into direct current, and current flowing into the power supply circuit of the external power supply is the direct current.

5. The charger according to any one of claims 1 to 4, wherein: the manual switch is a non-self-locking mechanical switch.

6. The charger of claim 5, wherein: the electronic switch is a relay, a triode, a silicon controlled rectifier or a solid state relay.

7. The charger of claim 6, wherein: the relay is provided with a coil and a triode, and the controller controls the conduction or the blocking of the triode to control whether the coil is electrified or not.

8. The charger of claim 7, wherein: the source of the electric energy flowing through the coil is the external power supply.

9. The charger of claim 5, wherein: when the manual switch is pressed, the charger immediately charges the battery.