JPH10275635A - Charge with built-in battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To charge both a preliminary battery and a built-in battery with a simple charge circuit for quickly charging the built in battery, efficiently supply the power of the preliminary battery to electronic equipment and bring the electronic equipment in convenient use in the condition that the built-in battery is discharged. SOLUTION: A charger 2 having a built-in battery has a case mounted on electronic equipment in a demountable manner. A preliminary battery 4 as a secondary battery to supply power to the electronic equipment 1 on which the case is mounted and a charge circuit to charge the preliminary battery 4 and a built-in battery 7 as a secondary battery built in the electronic equipment 1 and to be used with a power supply to supply power to the electronic equipment 1 are built in the case. The charger 2, when mounted on the electronic equipment 1, supplies power to the electronic equipment 1 with the charge circuit. The charge circuit charges the built-in battery 7 and the preliminary battery 4 at the same time or in sequence. When the charger 2 is removed from the electronic equipment 1, the charge circuit charges the preliminary battery 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charger for charging a secondary battery incorporated in an electronic device such as a mobile phone.

[0002]

2. Description of the Related Art A portable electronic device having a secondary battery built in a power supply can be used repeatedly by charging the battery. The built-in battery, which is a secondary battery, is charged by connecting a charger to the electronic device. When connecting the charger to charge the built-in battery, portable electronic devices are not portable. This is because the charger is connected to the commercial power supply via the power cord, and the electronic device is connected to the charger. For this reason, the electronic device charged by this charger cannot be carried and used with the built-in battery discharged.

In order to solve this drawback, a charger having a structure in which a charging circuit and a spare battery are separated has been developed. The spare battery is detachably mounted on the electronic device, and the spare battery is charged by the charging circuit. This charger has a feature that a fully charged spare battery can be attached to an electronic device and the built-in battery of the electronic device can be charged, so that the battery can be used while being carried while the built-in battery is discharged.

[0004]

However, the charger of this structure has the disadvantage that the charging circuit becomes complicated and the charging efficiency is deteriorated. The reason why the charging circuit is complicated is that a charging circuit for charging a spare battery with a commercial power supply and a charging circuit for charging the built-in battery are required. Further, the charging efficiency is deteriorated because the built-in battery is charged via the spare battery. In particular, if the voltage of the spare battery and the built-in battery are set to be the same so that the electronic device can be directly driven by the spare battery, the built-in battery cannot be charged unless the voltage of the spare battery is boosted. It is necessary to boost the voltage with a DC converter or the like, and the DC-DC converter has a disadvantage that the charging efficiency is further reduced.

Further, in the battery charger having this structure, the maximum value of the discharge current of the spare battery limits the charge current of the internal battery,
It can be difficult to quickly charge the built-in battery. In particular, when a secondary battery that is not suitable for high-current discharge characteristics, such as a lithium ion secondary battery, is used as a spare battery, there is a disadvantage that the charging time of the built-in battery becomes longer.

The present invention has been developed to solve this drawback. An important object of the present invention is to provide a built-in battery charger that can charge both a spare battery and a built-in battery with a simple charging circuit. Another important object of the present invention is to provide a battery charger having a built-in battery capable of rapidly charging a built-in battery and efficiently supplying power of a spare battery to an electronic device. Still another object of the present invention is to provide a battery charger having a built-in battery that can be used conveniently by carrying an electronic device with the built-in battery discharged.

[0007]

A charger incorporating a battery according to the present invention comprises a case 3 detachably attached to an electronic device 1.
Is provided. The case 3 is charged with a spare battery 4 which is a secondary battery for supplying power to the electronic device 1 to be mounted, and a spare battery 4 and a built-in battery 7 which is a secondary battery built in the electronic device 1. Further, a charging circuit used in combination with a power supply for supplying power to the electronic device 1 is incorporated. When the charger 2 is mounted on the electronic device 1, the charger 2 supplies power to the electronic device 1 by a charging circuit. Further, the charging circuit includes a built-in battery 7.
And the spare battery 4 are charged simultaneously or sequentially. When the charger 2 is disconnected from the electronic device 1, the charging circuit charges the spare battery 4.

In the battery charger according to a second aspect of the present invention, the case 3 containing the secondary battery and the charging circuit is separated from the AC adapter 5. The AC adapter 5 supplies DC power to the charging circuit. Since the charging circuit is supplied with DC power from the AC adapter 5, there is no need for a circuit including a transformer, a diode, and a capacitor for converting AC 100V, which is a commercial power supply, to a DC voltage for charging a battery. Also,
The output of the AC adapter 5 is controlled by a charging circuit and supplied to the electronic device 1, the spare battery 4, and the built-in battery 7.
A general-purpose product that is mass-produced can be used for the adapter 5.

[0009] Further, the charger of the present invention preferably comprises:
The charging circuit built in the case 3 charges the spare battery 4 after fully charging the built-in battery 7. That is, the built-in battery 7
Is charged in preference to the spare battery 4.

The charger of the present invention is controlled by a charging circuit built in the case 3 so that the battery 7 of the electronic device 1 is discharged first and then the spare battery 4 is discharged.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. However, the embodiments described below exemplify a charger for embodying the technical idea of the present invention, and the present invention does not limit the charger to the following.

Further, in this specification, in order to make it easier to understand the claims, the numbers corresponding to the members shown in the embodiments will be referred to as "claims" and "claims". In the column of “means”.
However, the members described in the claims are not limited to the members of the embodiments.

FIG. 1 shows a charger 2 mounted on an electronic device 1 which is a mobile phone. FIG. 2 shows a circuit diagram of the charger 2. The charger 2 shown in these figures has a case 3
Has a built-in spare battery 4 and a charging circuit.
The AC adapter 5 is connected to the charging circuit inside.

The case 3 has upper and lower locking portions 6 so that the case 3 can be detachably connected to the electronic device 1. Further, the case 3 has an elastic contact 8 that supplies power to the electronic device 1 while being attached to the electronic device 1 and supplies power for charging the built-in battery 7 of the electronic device 1. The elastic contact 8 is electrically connected to a power terminal (not shown) provided on the electronic device 1. Further, the case 3 also has an input terminal 9 connected to the AC adapter 5.

The elastic contact 8 includes a charging terminal 8A connected to the + side of the built-in battery 7 of the electronic device 1 and the electronic device 1, a voltage detection terminal 8B for detecting the voltage of the built-in battery 7,
A temperature terminal 8C for detecting the temperature of the internal battery 7, a control terminal 8D for controlling the charging of the internal battery 7,
-Eight terminal 8E.

The case 3 contains a printed circuit board 10. The printed board 10 fixes the spare battery 4, electronic parts constituting a charging circuit, and the elastic contact 8. The spare battery 4 is, for example, a secondary battery such as a lithium ion secondary battery, a nickel-cadmium battery, and a nickel-hydrogen battery.

The charging circuit controls the DC power supplied from the AC adapter 5 to charge the spare battery 4 and the built-in battery 7 of the electronic device 1, and further supplies power for driving the electronic device 1. I do.

The charging circuit shown in FIG.
And a DC-DC converter 11 for converting the DC input from the DC-DC converter into a charging voltage for the spare battery 4 and the built-in battery 7.
A microcomputer 12 for controlling the state of supplying the output of the DC converter 11 to the spare battery 4, the built-in battery 7, and the electronic device 1
A 5V power supply 13 for supplying power to the microcomputer 12, a first switching element S1 which is turned on and off by the microcomputer 12 to control the power supply to the electronic device 1, and a second switching element S1 for controlling the state of charge of the spare battery 4. 2 switching element S
2, a third switching element S3 for controlling the state of charge of the internal battery 7, a protection circuit 14 for the spare battery 4, and a current detection resistor R for detecting a current.

The DC-DC converter 11 converts a DC voltage supplied from the AC adapter 5 into a voltage that can charge the spare battery 4 and the built-in battery 7. When the spare battery and the built-in battery are lithium ion secondary batteries, the output voltage of the DC-DC converter is set to 4.1 to 4.2 V / cell.

The microcomputer 12 includes a spare battery 4 and a built-in battery 7.
To control the state of charge of the spare battery 4 and the built-in battery 7, and also control the power supply to the electronic device 1. The microcomputer 12 includes a first charge control switching element S
4 and the second charge control switching element S5 to control the state of charge of the spare battery 4 and the built-in battery 7, and to control the current supply to the electronic device 1. When the first charging control switching element S4 is turned on, the charging circuit performs DC-D
The output of the C converter 11 is supplied to the electronic device 1 to charge the internal battery 7 of the electronic device 1 and supply power to the electronic device 1. When the second charge control switching element S5 is turned on, the output of the DC-DC converter 11 is supplied to the spare battery 4, and the spare battery 4 is charged.

The microcomputer 12 includes a spare battery 4 and a built-in battery 7.
Of the first charge control switching element S4
And the second charge control switching element S5 is turned on / off as described below.

When the AC adapter 5 is connected to the charger 2 and the charger 2 is not attached to the electronic device 1. At this time, the voltage of the voltage detection terminal 8B becomes 0V. The microcomputer 12 detects the voltage of the voltage detection terminal 8B and
Is detected whether or not is mounted on the electronic device 1. At this time, the microcomputer 12 controls the second charge control switching element S5
Is turned on to charge the spare battery 4. When the spare battery 4 is fully charged, the microcomputer 12 turns off the second charge control switching element S5 to stop charging. At this time,
The microcomputer 12 turns off the first charge control switching element S4 and does not output DC.

When the charger 2 is attached to the electronic device 1 while the AC adapter 5 is connected to the charger 2 and the spare battery 4 incorporated in the charger 2 is being charged. The microcomputer 12 detects the voltage of the voltage detection terminal 8 </ b> B to detect that the charger 2 is connected to the electronic device 1. The microcomputer 12 switches on the first charge control switching element S4 to supply power to the electronic device 1. At this time, if the spare battery 4 is being charged, the microcomputer 12 switches the second charge control switching element S5 from ON to OFF, and stops charging the spare battery 4. Since the first charge control switching element S4 is on, the output of the charger 2 is
While supplying power to the electronic device 1, the built-in battery 7 can be charged. If the internal battery 7 is not fully charged, the microcomputer 12 turns on the third switching element S3 to charge the internal battery 7. When the internal battery 7 is fully charged, the microcomputer 12 turns off the third switching element S3 to stop charging the internal battery 7. After that, the microcomputer 12
The third switching element S3 is kept off, and the second charging control switching element S5 is turned on. The second charge control switching element S5 in the ON state is connected to the spare battery 4
Restart charging. When the spare battery 4 is fully charged, the microcomputer 12 switches off the second charge control switching element S5 to stop charging the spare battery 4. In this state, since the first charge control switching element S4 is in the ON state, the DC power supplied from the AC adapter 5 to the charger 2 is supplied to the electronic device 1.

When the charger 2 is connected to the electronic device 1 when the AC adapter 5 is connected to the charger 2 and the spare battery 4 incorporated in the charger 2 is not charged. That is, when the charger 2 is connected to the electronic device 1 after the spare battery 4 is fully charged. The microcomputer 12 detects the voltage of the voltage detection terminal 8 </ b> B to detect that the charger 2 is connected to the electronic device 1. The microcomputer 12 switches on the first charge control switching element S4 to supply power to the electronic device 1. Since the spare battery 4 is fully charged,
The second charge control switching element S5 is kept in the off state. Since the first charge control switching element S4 is on, the output of the charger 2 is set to a state where the built-in battery 7 can be charged while supplying power to the electronic device 1. Built-in battery 7
Is not fully charged, the microcomputer 12 turns on the third switching element S3 to charge the internal battery 7. When the internal battery 7 is fully charged, the microcomputer 12 turns off the third switching element S3 to stop charging the internal battery 7.
In this state, the first charge control switching element S4
Is in the ON state, the DC power supplied from the AC adapter 5 to the charger 2 is supplied to the electronic device 1.

When the charger 2 is mounted on the electronic device 1 with the AC adapter 5 not connected to the charger 2. A
When the C adapter 5 is not connected to the charger 2, the voltage applied to the power supply terminal 15 of the microcomputer 12 is 0V.
This is because the power supply terminal 15 is connected to the input terminal 9 of the charger 2. Therefore, the microcomputer 12 detects the voltage of the power supply terminal 15 and determines whether the AC adapter 5 is connected. When the voltage of the power supply terminal 15 becomes 0 V and the AC adapter 5 is not connected to the charger 2,
The microcomputer 12 detects the remaining capacity of the internal battery 7, and when the internal battery 7 can be discharged, takes precedence over the spare battery 4,
The internal battery 7 is discharged first and the electronic device 1 is driven by the internal battery 7. After the internal battery 7 is discharged, the spare battery 4 is discharged.

When power for driving the microcomputer 12 is no longer supplied from the AC adapter 5, the spare battery 4
2 is powered. The microcomputer 12 is supplied with power from either the AC adapter 5 or the spare battery 4. To realize this, the + side of the spare battery 4 is connected to the microcomputer 12 via the discharge switching element S6 and the booster circuit 16.
Connected to. When the AC adapter 5 is not connected to the charger 2, the microcomputer 12 controls the discharge switching element S6 to be turned on. Discharge switching element S6 in ON state
Supplies driving power from the spare battery 4 to the microcomputer 12.

Further, the booster circuit 16 outputs an output of DC-D
Since it is connected to the C converter 11, when the discharge switching element S6 is controlled to be turned on and the first charge control switching element S4 is controlled to be turned on, power is supplied from the spare battery 4 to the electronic device 1. Therefore, the spare battery 4
When the microcomputer 12 supplies power to the electronic device 1, the microcomputer 12 controls the discharge switching element S6 and the first charge control switching element S4 to be turned on.

The charger incorporating the battery of the above embodiment is
The case 3 mounted on the electronic device 1 does not include a transformer and a diode for converting a commercial power supply into a direct current and converting the voltage into a direct current.
DC power is supplied from the C adapter 5 to the charging circuit. Therefore, the charging circuit can be made compact. In particular, since a large and heavy transformer is built in the AC adapter 5, the charging circuit can be made small and lightweight. Since the AC adapter 5 does not control the charging of the spare battery 4 and the built-in battery 7, an AC adapter that is manufactured in large numbers at low cost and is commercially available for general use can be used.

However, the charger incorporating the battery of the present invention is:
As shown in the circuit diagram of FIG. 3, a transformer 17 and a diode 18 can be built in the case.

[0030]

The charger incorporating a battery according to the present invention has a feature that both a spare battery and a built-in battery can be charged with a simple charging circuit. This is because the charging circuit of the spare battery built in the charger is used together with the charging circuit of the built-in battery built in the electronic device. Further, the charging circuit of the spare battery and the built-in battery can be used together with a power supply circuit for stably driving the electronic device, if necessary.

Further, the battery charger incorporating the battery of the present invention does not charge the internal battery of the electronic device with the built-in spare battery, but controls the power input from an AC adapter or the like by a charging circuit. Since the built-in battery is charged, both the built-in battery and the spare battery can be quickly charged in a short time. In addition, the charger of the present invention charges a spare battery,
Instead of charging the built-in battery with this spare battery, the power input from the AC adapter etc. is controlled by the charging circuit,
After the built-in battery is charged and the built-in battery is discharged, power is supplied from the spare battery to the electronic device, so that the electronic device can be efficiently driven by the power charged in the spare battery.

Further, the battery charger incorporating the battery of the present invention incorporates a spare battery for driving electronic equipment. Therefore, when the charger is attached while the built-in battery is discharged, the electronic device can be driven by the charger. Therefore, it is also possible to realize a feature that the electronic device can be used in a portable state by attaching a charger after discharging the built-in battery.

Further, in the battery charger incorporating the battery according to the second aspect of the present invention, the case mounted on the electronic device and the AC adapter are separated. The AC adapter supplies DC power to a charging circuit built in the case. The charging circuit is A
By controlling the DC power supplied from the C adapter, the spare battery and the built-in battery are charged, and further, the electronic device is driven. The charger with this structure not only allows the case to be mounted on the electronic device to be small and lightweight,
There is no need to incorporate a charging circuit for charging the spare battery and the built-in battery, and a general-purpose product generally used can be used.
For this reason, there is a feature that the entire manufacturing cost can be reduced and that it can be used extremely conveniently.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which a charger incorporating a battery according to an embodiment of the present invention is mounted on an electronic device.

FIG. 2 is a circuit diagram of the charger shown in FIG. 1;

FIG. 3 is a circuit diagram of a charger including a battery according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electronic device 2 ... Charger 3 ... Case 4 ... Spare battery 5 ... AC adapter 6 ... Locking part 7 ... Built-in battery 8 ... Elastic contact 8A ... Charging terminal 8B
... voltage detection terminal 8C ... temperature terminal 8D ... control terminal 8
E ...- terminal 9 ... input terminal 10 ... printed circuit board 11 ... DC-DC converter 12 ... microcomputer 13 ... 5V power supply 14 ... protection circuit 15 ... power supply terminal 16 ... boost circuit 17 ... transformer 18 ... diode S1 ... first switching element S2 ... second switching element S3 ... third switching element S4 ... first charge control switching element S5 ... second charge control switching element S6 ... discharge switching element R ... current detection resistor

Claims (4)

[Claims] 1. A case (3) detachably attached to an electronic device (1), and a secondary battery built in the case (3) and supplying power to the attached electronic device (1). Some spare batteries (4)
And the built-in battery (7), which is a secondary battery built in the spare battery (4) and the electronic device (1), and
A charging circuit used in combination with a power supply for supplying power to (1), wherein the charging circuit is mounted on the electronic device (1), and
Supply power to (1), as well as the built-in battery (7) and spare battery
A charger incorporating a battery configured to charge the spare battery (4) simultaneously or sequentially, and to charge the spare battery (4) when disconnected from the electronic device (1). 2. A case (3) detachably attached to the electronic device (1) and a secondary battery which is built in the case (3) and supplies power to the attached electronic device (1). Some spare batteries (4)
And the built-in battery (7), which is a secondary battery built in the spare battery (4) and the electronic device (1), and
A charging circuit that is used in combination with a power supply that supplies power to (1), and A that supplies DC power to the charging circuit that is built in case (3).
A power supply from the AC adapter (5) is supplied to the electronic device (1) while being attached to the electronic device (1).
By controlling the direct current supplied from the C adapter (5), the built-in battery (7) and the spare battery (4) are charged simultaneously or sequentially, and the AC adapter is removed from the electronic device (1).
A charger incorporating a battery configured to control the direct current supplied from (5) to charge the spare battery (4). 3. The battery charger according to claim 1, wherein the charging circuit built in the case (3) charges the spare battery (4) after fully charging the built-in battery (7). . 4. The battery charger according to claim 1, wherein the charging circuit built in the case (3) discharges the spare battery (4) after discharging the built-in battery (7). .