JPH04109829A - Charger - Google Patents

Abstract

PURPOSE:To equalize the charging time of respective chargeable batteries, when a plurality of chargeable batteries are charged, by determining a charging current value corresponding to the residual capacity of each chargeable battery determined through a residual capacity recognizing circuit and then controlling a constant current circuit. CONSTITUTION:Residual capacity recognizing circuits 621-62n operate the discharged capacities when charging sections 61-6n are connected with loads. A CPU 7 receives residual capacity signals from the residual capacity recognizing circuits 621-62n and outputs signals for controlling constant current circuits 51-5n. In other words, charging current is regulated so that the plurality of chargeable batteries 611-61n finish charging operation at same time point.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a charger capable of charging a plurality of rechargeable batteries.

[Prior art] Conventionally, this type of charger has a power source 1, as shown in Fig. 2.
From constant current circuit 2□~2. , through the charging section 3. ~3
．． Rechargeable battery inside 31. ~31. It is designed to be charged. Power source 1, constant current circuit 2 to general circuit, and rechargeable battery 31. ~31
．． is housed in the case 4, and the charging section 3. ~3. ．． is installed removably from the case 4. Charging part 3
1 to 3 degrees respectively to the case 4, and the constant current circuits 2, to 2. ．． A rechargeable battery 31. as a secondary battery of each charging unit 31-3 is connected to the rechargeable battery 31. After charging is completed, each charging section 31-3o is removed from the case and power is supplied from the terminals 321-32° of the charging section 31-3o to a load (not shown).

[Invention or problem to be solved]

However, in the above-mentioned charger, the rechargeable batteries 31. When charging at ~31°, constant current circuit 2,
Since the charging current from ~26 is constant, if the remaining capacity of each rechargeable battery 311~31, , before charging (the capacity remaining in the rechargeable battery at that time) is not constant, each rechargeable battery 31. The charging time to ~31° is not constant. In other words, a device with low remaining capacity will take a long time to charge, and a device with a large remaining capacity will finish charging quickly.The total charging time will depend on the device with the lowest remaining capacity, and will depend on the charging efficiency. There was a problem with it being bad.

The present invention has been made in view of the above points, and its purpose is to provide a charger that can equalize the charging time for each rechargeable battery when charging a plurality of rechargeable batteries. It's about doing.

[Means to solve the problem]

The present invention includes a plurality of constant current circuits, and a plurality of charging parts that charge a rechargeable battery using charging current from the constant current circuits, which are housed in a case, and further, the charging parts are removably installed in the case. In the charger, the constant current circuit is a circuit that can divide the value of the charging current, and the charging unit includes a remaining capacity recognition circuit that determines the remaining capacity in the rechargeable battery before starting charging and outputs a remaining capacity signal. and a CPU that determines the charging current value of the constant current circuit from the remaining capacity signal from the remaining capacity recognition circuit and outputs a control signal to control the constant current circuit. be.

[Effect]

In the charger of the present invention, the remaining capacity of the rechargeable battery to be charged is determined by the remaining capacity recognition circuit provided in the plurality of charging parts removably installed in the case, and the CPU calculates the remaining capacity of the rechargeable battery to be charged.
The charging current value is determined according to the remaining capacity of each rechargeable battery determined by the remaining capacity recognition circuit, and the constant current circuit is controlled.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings. 1st
The figure is a block diagram showing one embodiment of the present invention. 51
~5o is a constant current circuit, which outputs a charging current by supplying power from the power source l.

This charging current value is determined by a control signal from the CPU, which will be described later. 6. ~6. ．． is a charging unit that is removably installed in the case 4, and includes a rechargeable battery 61 as a secondary battery that is charged by charging current from constant current circuits 51 to 57.
．． ~61. and each rechargeable battery 61+ to 61. Remaining capacity recognition circuit 62. calculates the remaining capacity of , and sends a remaining capacity signal as a digital signal to the CPU, which will be described later. ~62. , resistors 63 to 63□ for detecting the charging current at that time, and a load (
(not shown) and terminals 641 to 64°.

Here, rechargeable batteries 611 to 61. The remaining capacity of the battery is determined by subtracting the product of the load current and the time during which the load current is applied (discharge capacity) from the product of the charging current and the time required for charging (charging capacity). Therefore, the remaining capacity recognition circuit 62. ~624
is the charging part 6. 64 is connected to a load, that is, while it is being used as a secondary battery, the discharge capacity is calculated. 7 is the CPU and remaining capacity recognition circuit 62+~6
In response to the remaining capacity signal from 2°, it outputs a control signal for controlling the current value of the constant current circuits 51 to 5°.

In other words, the charging flow is adjusted so that charging of each of the plurality of rechargeable batteries 611 to 61fi is completed in the same amount of time. For example, when charging the two charging parts 6 and 62, the charging part 6
．． If the remaining capacity of the rechargeable battery 61□ in the charging section 62 is 20%, and the remaining capacity of the rechargeable battery 61□ in the charging section 62 is 80%, then the constant current circuit 5□ is set to a current value of 80% of the total charging current. ,
The constant current circuit 52 is set to a current value of 20% of the total charging current.

A D/A converter 8 converts the digital control signal output from the CPU 7 into an analog signal, and connects each constant current circuit 5. It sends a control signal to ~5o. 4 is the case,
It houses each of the circuits mentioned above. However, charging part 6. -6 are removably stored.

〔Effect of the invention〕

As described above, according to the present invention, the remaining capacity of the rechargeable battery to be charged is determined by the remaining capacity recognition circuit included in the plurality of charging units removably installed in the case, and the CPU determines the remaining capacity of the rechargeable battery to be charged. Since the charging current value is determined according to the remaining capacity of each rechargeable battery determined by the recognition circuit and the constant current circuit is controlled, when charging multiple rechargeable batteries, the charging time for each rechargeable battery can be adjusted. We were able to provide a charger that can do the same thing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example. 1. - Power supply 4. Cases 51 to 5. Constant current circuit 61-6o1. Charging part 7--CPU
8-D/A converter 61+ to 61. - Rechargeable batteries 621 to 62o - Remaining capacity recognition circuits 631 to 63. , - Resistor 641~64n One terminal patent applicant Matsushita Electric Works Co., Ltd. agent Patent attorney Shigeji Sahara (and one other person) Figure 2

Claims (1)

[Claims] (1) A plurality of constant current circuits and a plurality of charging parts that charge a rechargeable battery using charging current from the constant current circuits are housed in a case, and the charging parts are removably installed in the case. In the charger, a circuit capable of controlling the value of charging current is used as the constant current circuit, and a remaining capacity recognition circuit that determines the remaining capacity in the rechargeable battery before starting charging and outputs a remaining capacity signal in the charging unit; A charger comprising: a CPU that calculates a charging current value of the constant current circuit from a remaining capacity signal from the remaining capacity recognition circuit and outputs a control signal to control the constant current circuit.