JPH07322517A - Method and apparatus for charging - Google Patents

Abstract

PURPOSE:To provide a charging method and a charging apparatus whose energy efficiency is high by performing a charging operation by making use of electric energy which is left inside a charging battery which has been used. CONSTITUTION:When a charging battery 12m which is undischarged, i.e., which is waiting for a discharge operation, and a charging battery 121 which has been.discharged, i.e., which is waiting for a charging operation,are contained in a plurality of charging batteries 121,...12n, the charging battery 12m which is waiting for the discharge operation is connected to input terminals of a DC-voltage conversion circuit 28, and the charging battery 121 which is waiting for the charging operation is connected to the output side of the DC-voltage conversion circuit 28. That is to say, when the discharged charging battery 121 is charged by using electric energy which is left in the undischarged charging battery 12m, the undischarged charging battery 12m is discharged, and, at the same time, the discharged charging battery 121 is charged. Consequently, the electric energy which is consumed wastefully in conventional cases and which is left in the used charging battery 12m can be utilized effectively to charge other batteries, and the high energy efficiency of a charging method and a charging apparatus can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device connected to a plurality of rechargeable batteries to charge them.

[0002]

2. Description of the Related Art Rechargeable rechargeable batteries such as Ni-Cd batteries and Ni-MH batteries are used for video cameras, portable televisions, portable tape recorders, portable tape reproducing devices, portable CDs.
It is often used as a power source for portable electric devices such as playback devices. It is desirable that such a rechargeable battery be recharged in a state in which the energy remaining in the battery is released so that the memory effect in which the voltage drop after the start of use occurs early does not occur.

On the other hand, conventionally, before connecting the used rechargeable battery removed for recharging to the charger, the used rechargeable battery is connected to the discharger, respectively, and the inside of them is connected. Of the remaining electric energy is sufficiently released.

[0004]

By the way, in the conventional case as described above, it is necessary to connect the rechargeable battery to the discharger and once discharge it, and then connect to the charger to charge the rechargeable battery. There is a drawback that the electric energy remaining in the is converted into heat and wasted in vain.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to achieve high energy efficiency by charging using the electric energy remaining in the rechargeable battery after use. It is to provide an obtained charging method and charging device.

[0006]

The first aspect of the present invention for achieving the above object is to sequentially discharge a plurality of undischarged rechargeable batteries, and then to discharge the recharged batteries. Is a sequential charging method, by charging the discharged rechargeable battery using the electrical energy remaining in the undischarged rechargeable battery, to discharge the undischarged rechargeable battery at the same time It is about charging a rechargeable battery that has been discharged.

[0007]

In this way, by charging the discharged rechargeable battery with the electric energy remaining in the undischarged rechargeable battery, the undischarged rechargeable battery is discharged. At the same time, the discharged rechargeable battery is charged. Therefore, according to the method of the present invention, since the electric energy remaining in the used rechargeable battery, which has been wasted in the past, is effectively used for charging the other rechargeable battery,
High energy efficiency is obtained. Further, according to the charging method of the present invention, since the charging of the discharged rechargeable battery is performed at the same time as the discharging of the undischarged rechargeable battery, the discharge time is longer than that in the case where the rechargeable batteries are individually discharged and then respectively charged. Is unnecessary, and there is an advantage that the charging efficiency is substantially increased.

[0008]

A second object of the present invention to achieve the above object is to provide a charging device connected to a plurality of rechargeable batteries for charging them. a) a charging circuit that outputs a charging voltage for charging the rechargeable battery, (b) a DC voltage conversion circuit that converts the DC voltage input from the input terminal into a charging voltage and outputs the charging voltage, and (c)
Selective connecting means for selectively connecting the plurality of rechargeable batteries to the charging circuit and the DC voltage conversion circuit, respectively (d)
An undischarged rechargeable battery of the plurality of rechargeable batteries is connected to a power input terminal of the DC voltage conversion circuit, and a discharged rechargeable battery of the plurality of rechargeable batteries is connected to the output side of the DC voltage conversion circuit. And a control means for connecting to.

[0009]

With this configuration, the charging circuit that outputs the charging voltage for charging the rechargeable battery, the DC voltage converting circuit that converts the DC voltage input from the input terminal into the charging voltage and outputs the charging voltage, and Selective connection means for selectively connecting each of the rechargeable batteries to the charging circuit and the DC voltage conversion circuit is provided, and by the control means, an undischarged rechargeable battery among the plurality of rechargeable batteries is The discharged rechargeable battery of the plurality of rechargeable batteries is connected to the power supply input terminal of the DC voltage conversion circuit and is connected to the output side of the DC voltage conversion circuit.

[0010]

Therefore, according to the charging apparatus of the present invention, the charging voltage is output based on the electric energy remaining in the undischarged rechargeable battery in the DC voltage conversion circuit, and the charging voltage has already been discharged. Since the rechargeable battery is charged, the electric energy remaining in the used rechargeable battery is effectively used for charging the other rechargeable batteries, so that high energy efficiency is obtained.

Further, according to the charging device of the present invention, the uncharged rechargeable battery among the plurality of rechargeable batteries connected to the charging device is discharged and the discharged rechargeable battery is charged at the same time.
As compared with the case where the rechargeable batteries are individually discharged and charged, there is an advantage that the discharge time becomes unnecessary and the charging efficiency is substantially increased.

[0012] Preferably, the control means controls the charging circuit for charging the discharged rechargeable battery when there is no undischarged rechargeable battery among the plurality of rechargeable batteries. It is configured to connect to the output side. By doing this, when there is no undischarged rechargeable battery among the plurality of rechargeable batteries connected to the charging device, the discharged rechargeable battery to be charged is on the output side of the charging circuit. Since the connection is automatically made, there is an advantage that the rechargeable battery to be charged is charged without waiting for the connection of the undischarged rechargeable battery.

Further, preferably, a discharging circuit for discharging an undischarged rechargeable battery among the plurality of rechargeable batteries is further provided, while the selective connecting means includes the plurality of rechargeable batteries. The control means is configured to be selectively connected to a discharge circuit, and the control means discharges an undischarged rechargeable battery when there is no discharged rechargeable battery among the plurality of rechargeable batteries. Is configured to connect to that discharge circuit. With this configuration, when there is no discharged rechargeable battery among the plurality of rechargeable batteries connected to the charging device, the already connected undischarged rechargeable battery is discharged by the discharge circuit. , There is an advantage that a rechargeable battery that has already been discharged is automatically prepared.

Further, preferably, a charging completion display means for respectively indicating that the plurality of rechargeable batteries are in a charged state is further provided, and the control means is charged by the plurality of rechargeable batteries. It further includes charge completion determination means for determining whether or not the battery is in a charged state, and display control means for displaying a charge completion display means corresponding to the rechargeable battery determined to be in the charged state. In this way, which of the plurality of rechargeable batteries connected to the charging device is in the charging completed state is displayed, so that it is possible to prevent the rechargeable battery that has not been charged from being mistakenly reused. There are advantages.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a charging device 10 according to an embodiment of the present invention.
3 is a block diagram showing the configuration of FIG. In the figure, a plurality of rechargeable batteries 12 ₁ ... 12 _n (n = arbitrary integer) are, for example, Ni-Cd batteries of the same standard.
The plurality of connection locations 16 ₁ ... 16 _n (n = an arbitrary integer) at 4 are electrically connected to the pair of terminals.

[0016] On the other hand, in the charging device 10, an input terminal 20 for connection to either the rechargeable battery 12 _n, the constant current from the connected to the input terminal 20 the battery 12 _n of + terminal Discharge circuit 22 for discharging by means of a rechargeable battery 12 _n
A DC voltage conversion circuit 28 that has an input terminal 24 for connecting to any of the input terminals 24 and that converts the voltage of the + terminal of the rechargeable battery 12 _n connected to the input terminal 24 into a charging voltage and outputs the charging voltage from the output terminal 26. , An output terminal 30 for connecting to any of the rechargeable batteries 12 _n , and a charging voltage generated based on the electric power supplied from the power supply line
The charging circuit 32 for applying to the + terminal of the rechargeable battery 12 _n connected to 0 and a plurality of sets of relay terminals are provided, and the discharging line 34 is connected to the input terminal 20 of the discharging circuit 22 and the DC voltage converting circuit 2
First, the charging line 36 is selectively connected to the output terminal 26 of the DC voltage converting circuit 28 and the output terminal 30 of the charging circuit 32 while being selectively connected to the input terminal 24 of
A connection circuit 38 and a plurality of sets of relay terminals are provided, and the discharge line 34 is selectively connected to the + terminal of each rechargeable battery 12 _n , and the charge line 36 is selectively connected to the + terminal of each rechargeable battery 12 _n. Second connection circuit 40 and the first connection circuit 38
And a control circuit 42 for controlling the switching state of the second connection circuit 40, a discharge-indicating lamp provided for each rechargeable battery 12 _n to indicate that the rechargeable battery 12 _n is being discharged, is being charged, or has been charged. 44 _D , a charging indicator lamp 44 _C , and a charging completion indicator lamp 44 _F are provided with a display device 44 that lights according to a command from the control circuit 42. In FIG. 1, the negative terminal of the rechargeable battery 12 _n has the same connection as the positive terminal and is omitted.

The discharge circuit 22 is composed of a current discharge circuit for controlling the discharge current I _D to be substantially constant, as shown in FIG. 2, for example. That is, between the input terminal 20 and the ground, the discharge current controlling transistor 50 connected in series and the resistor 5 connected in series with the resistor 52.
4 and the Zener diode 56 are connected in parallel with each other, and the base potential of the discharge current controlling transistor 50 is kept constant by the Zener diode 56, regardless of the change in the potential of the input terminal 20. The discharge current control transistor 50 operates so that the current flowing through the resistor 52 becomes substantially constant. The voltage of the input terminal 20 at the time of discharging, that is, the discharging voltage V _D is supplied to the control circuit 42.

The DC voltage conversion circuit 28 is constructed in the same manner as a voltage converter known as a so-called DC-DC converter, and has a predetermined rechargeable battery 12 _m to be discharged as a power source and an input terminal. 24, the input voltage generated by the electric energy remaining in the predetermined rechargeable battery 12 _m is converted into the charging voltage V _C , and the output terminal 26 is connected.
Is output to another rechargeable battery 12 _n to be charged. That is, the DC voltage conversion circuit 28 is composed of a voltage dividing circuit including a pair of resistors connected in series as shown in FIG. 3, and the rechargeable battery 1 connected to the input terminal 24.
An input voltage detection circuit 58 for outputting a signal SV _D representing the discharge voltage V _D by detecting the terminal voltage or the discharge voltage V _D of 2 _m to the control circuit 42, from the control circuit 42 by boosting an input voltage A rechargeable battery connected to the output terminal 26, which includes a booster circuit 60 that generates a charging voltage V _C according to the current command signal SI and outputs the charging voltage V _C from the output terminal 26, and a voltage dividing circuit including a pair of resistors connected in series. 12 _n detects a terminal voltage or the charging voltage V _C of the charging voltage V _C
A rechargeable battery 12 _n connected to the output terminal 26, which is composed of an output voltage detection circuit 62 that outputs a signal SV _C that indicates to the control circuit 42 and a current detection resistor that has an extremely low resistance value.
Charging current detection circuit 64 for outputting a signal SI _C that detects the charging current I _C by representing the charging current I _C to the control circuit 42
It has and.

In the booster circuit 60, the current command signal SI
Is provided with a drive pulse generation circuit 66 that outputs a PWM signal that is pulse-modulated with a duty ratio according to the above. The transistor 68 is opened and closed in response to this PWM signal to generate an induced electromotive force in the coil 70. , The capacitor 74 is charged through the diode 72. The voltage charged in the capacitor 74, that is, the charging voltage V
_C is changed according to the duty ratio of the PWM signal, that is, the current command signal SI. Control circuit 4
2 outputs the current command signal SI so that the actual charging current I _C matches the preset target value, so that the charging voltage V _C is adjusted according to the current command signal SI.

The charging circuit 32 is, for example, as shown in FIG.
As shown in, a rectifying / smoothing circuit 76 for converting the voltage from the AC power supply line to a low voltage and rectifying and smoothing the low voltage AC current to a DC, and a DC current output from the rectifying / smoothing circuit 76 And a constant current circuit 78 that outputs a constant charging current I _C set in advance from the output terminal 30. The voltage of the output terminal 30 at the time of charging, that is, the charging voltage V _C is also supplied to the control circuit 42.

The control circuit 42 includes a CPU, ROM, R
A so-called microcomputer including an AM and the like is provided, and the CPU uses the temporary storage function of the RAM to advance the R
The input signal is processed in accordance with the program stored in the OM to control the switching states of the first connection circuit 38 and the second connection circuit 40, and the direct-current voltage conversion circuit 28.
The charging current I _C output from is controlled to be constant.

FIG. 5 is a functional block diagram for explaining a main part of the control function of the control circuit 42. In the figure, a plurality of rechargeable batteries 12 ₁ ... 12 _n are connected to the first connection circuit 3
8 and the second connecting circuit 40 corresponding to the selective connecting means 90
The charging circuit 32, the DC voltage converting circuit 28, and the discharging circuit 22 are selectively connected via the. The control means 92 corresponding to the control circuit 42 includes a plurality of rechargeable batteries 12 ₁ connected to the selective connection means 90.
- 12 to sequentially determine the actual state of _n, respectively determines the discharge waiting determining means that they are undischarged state, that discharge wait state for each battery 12 _n 94
And a discharge-in-progress determining means 96 for determining that each of the rechargeable batteries 12 _n is being discharged, and a charge-waiting determining means for determining that each of the rechargeable batteries 12 _n is in a discharged state, that is, a charge-waiting state. 98, the charging in determination unit 100 determines that they are being charged for each rechargeable battery 12 _n, and each comprise a charging completion determination means 102 determines that charging is complete for each of these rechargeable battery 12 _n.

Among the plurality of rechargeable batteries 12 ₁ ... 12 _n , the control means 92 is a non-discharged or recharged rechargeable battery 12 _m and a discharged or recharged rechargeable battery 12 _m.
If there is _l (m ≠ l), the rechargeable battery 1 waiting to be discharged
2 _m is connected to the input terminal 24 of the DC voltage conversion circuit 28, and the rechargeable battery 12 _l waiting for charging is connected to the output terminal 26 of the DC voltage conversion circuit 28. However, if there is a rechargeable battery 12 _l waiting to be charged among the plurality of rechargeable batteries 12 ₁ ... 12 _n but no rechargeable battery 12 _m waiting to be discharged, the rechargeable battery 12 _l waiting to be charged is charged. Is connected to the output side of the charging circuit 32. In addition, the plurality of rechargeable batteries 12 ₁ ··· 1
If there is a rechargeable battery 12 _m waiting to be discharged in 2 _n but there is no rechargeable battery 12 _l waiting to be charged, a rechargeable battery 12 waiting to be discharged 12
Connect to discharge circuit 22 to discharge _m .

Further, a plurality of rechargeable batteries 12₁・ ・ 12_n
Before to show that each is in a charged state
Charging completion indicator lamp 44_FCharging completion display hand corresponding to
A stage 104 is provided, and the control means 92 includes a plurality of stages.
Several rechargeable batteries 12₁・ ・ 12 _nIs in a charged state.
A display indicating that the one that is judged to have been charged is charged.
The display control means 106 for making the power completion display means 104 perform
Further included.

The main part of the control operation of the control circuit 42 will be described below.
According to the flowcharts of FIGS. 6, 7 and 8.
Reveal FIG. 6 shows that each rechargeable battery 12 has a relatively short fixed period.
_nOf the status flags set for each, a discharge wait flag
F_DW, Charging wait flag F_CW, Charging completion flag F_FSet
FIG. 7 and FIG.
Is each rechargeable battery 12_nDischarging flag among the status flags
F_DAnd charging flag F _CAnd set
Connection state of the first connection circuit 38 and the second connection circuit 40
Is a switching control routine for controlling the.

Step SW1 of FIG. 6 (hereinafter, step
(Omitted) is a rechargeable battery with the status flag set.
12_nIt is determined whether or not is connected. This SW
If the determination of 1 is affirmative, SW3 is executed, but
If specified, rechargeable battery 12 _nIs the connection of the battery socket 14
Continued place 16_nWas removed during discharge or charging
The rechargeable battery 12 removed in SW2_n
Status flags for all were reset to "0"
After that, SW3 is executed. The judgment of SW1 above is based on the connection field.
Location 16_nJudgment is made based on the change in the terminal voltage of the. charging
Pond 12_nIs about 0.8 to 1.2V per cell
This is because the voltage is generated.

In SW3, the status flag is reset.
Connected place 16_nRechargeable battery 12_nWas connected
Whether or not the connection place 16_nBased on the change in the terminal voltage of
To be judged. If the determination of SW3 is negative, SW
5 is executed, but if affirmative, put in SW4
And the newly connected rechargeable battery 12_nDischarging wait flag F
_DWSW5 is executed after the content of is set to "1"
It

At the subsequent SW5, it is determined whether or not the charging of the rechargeable battery 12 _{n for} which the charging flag F _C is set is completed.
For example, the determination is made based on whether or not the charging voltage V _C has dropped from the voltage V _{CP at the} peak point by a predetermined determination reference value Δv ₁ or more. As shown in FIG. 9, the rechargeable battery 12 _n has a property that the charging voltage V _C forms a peak point before the end of charging and decreases thereafter, so that the charging voltage V _C is stored and peaked for each interrupt. The point voltage V _CP is calculated, and the decrease amount Δv from the peak point voltage V _CP is calculated, and it is judged whether or not the decrease amount Δv exceeds the judgment reference value Δv ₁ . If the determination of SW5 is negative, SW7 is executed, but if the determination of SW5 is affirmative, the content of the charging completion flag F _F of the rechargeable battery 12 _n for which the completion of charging is determined is set to "1" in SW6. After that, the SW7 is executed and the charging completion display lamp 44 _F corresponding to the connection location of the rechargeable battery 12 _n is turned on.

In the SW7, it is determined whether or not the rechargeable battery 12 _{n for} which the discharging flag F _D is set is discharged.
It is determined based on the terminal voltage. When the determination of SW7 is denied, this routine is ended, but when the determination is affirmative, the content of the charging wait flag F _CW of the rechargeable battery 12 _n , which has been determined to be discharged, is set to "1" in SW8. After being set, this routine is ended.

When the content of the charging completion flag F _F is set to "1", the current command signal SI is output so that the supply of the charging current I _C to the corresponding rechargeable battery 12 _n is cut off. At the same time, the connection with the DC voltage conversion circuit 28 or the charging circuit 32 is cut off at SA9 described later.

In the routine shown in FIG. 6, the SW
3 corresponds to the discharge wait determination means 94, SW7 corresponds to the charge wait determination means 98, SW5 corresponds to the charge completion determination means 102, and SW8 corresponds to the display control means 106.

In the determination step of the switching control routine of FIGS. 7 and 8, each state flag F _DW , F _D , F _CW , F _C , F _F set by the routine of FIG. 6 or set in a step described later is set. The judgment is executed based on the contents of. First, when the rechargeable battery 12 _n is not connected to any of the battery sockets 14 _n , or when the connected rechargeable battery 12 _n is in the charging completed state, SA1,
Since the determinations at SA6, SA10, and SA14 are denied, the switching control and the charging / discharging are suspended at SA16.

In this state, when the used rechargeable battery 12 _n is connected to one of the battery sockets 14 _n , the discharge wait flag F _DW of the rechargeable battery 12 _n should be set to "1". Since the determination of SA10 is affirmative and the determination of SA11 is negative, the rechargeable battery 12 _n is connected to the discharge circuit 22 to start its discharge at SA13 and the corresponding rechargeable battery 12 _n is being discharged. The content of the flag F _D is set to "1" and the content of the other status flags F _DW , F _CW , F _C and F _F are cleared to "0". Further, in the next cycle, the determination of SA6 is affirmative and the determination of SA7 is negative, so that the rechargeable battery 12 _n is connected to the discharging circuit 22 and the discharging is continued at SA9, similarly to SA13. And this rechargeable battery 1
When the discharge of 2 _n is completed, the charge waiting flag F _CW is set to "1", so the determination of SA10 is negative and the determination of SA14 is affirmative, so that the charging circuit 32 is connected at SA15 and The content of the charging flag F _C of the rechargeable battery 12 _n waiting for charging is set to “1” and the contents of the other status flags F _DW , F _CW , F _D , and F _F are cleared to “0”.

12 _l of rechargeable battery waiting to be charged is the battery socket 1
When the rechargeable battery 12 _m after use is also connected to the other battery socket 14 _m when connected to 4 _l , the above SA1
Since both 0 and SA11 are affirmed, SA1
In 2 the rechargeable battery 12 _m with the rechargeable battery 12 _l is connected to the output terminal 26 of the DC voltage conversion circuit 28 is connected to the input terminal 24 of the DC voltage conversion circuit 28, and discharging the rechargeable battery of the rechargeable battery 12 _m 12 _l charging is done at the same time. As a result, the remaining electric energy of the rechargeable battery 12 _m is used to charge the rechargeable battery 12 _l . At the same time, in the SA12, the contents of the charging flag F _C for the battery 12 _l is set to "1" and the other state flag F
The contents of _DW , F _CW , F _D , and F _F are cleared to “0”, the content of the discharging flag F _D for the rechargeable battery 12 _m is set to “1”, and other status flags F _DW and F D _CW ,
The contents of F _C and F _F are cleared to “0”.

Even when the rechargeable battery 12 _l waiting to be charged is connected to the battery socket 14 _l while the rechargeable battery 12 _m is being discharged, the determinations at SA6 and SA7 are both affirmative, so that the rechargeable battery at 12 is charged at SA8. The battery 12 _l is connected to the output terminal 26 of the DC voltage conversion circuit 28, and the rechargeable battery 12 _m is connected to the input terminal 24 of the DC voltage conversion circuit 28.
The rechargeable battery 12 _m is discharged and the rechargeable battery 12 _l is charged at the same time. At the same time, in SA8, the content of the charging flag F _C for the rechargeable battery 12 _l is set to “1” and the other status flags F _DW , F _CW , F _D , and F _{F are set.}
Is cleared to "0".

When the above SA12 or SA8 is executed, the rechargeable battery 12 _m is being discharged and the rechargeable battery 12 _l is being charged. Therefore, in the next cycle, SA1 and S1 are discharged.
Since the determinations of A2 are both affirmative, this routine is ended and the DC voltage conversion circuit 28 continues discharging the rechargeable battery 12 _m and charging the rechargeable battery 12 _l .

While the above cycle is repeatedly executed, if the discharge of the rechargeable battery 12 _m is completed first, SA2
Is denied, it is determined in SA3 whether or not there is another rechargeable battery waiting to be discharged. If the determination at SA3 is affirmative, and if the other rechargeable battery waiting to be discharged is, for example, 12 _{m + 1} , at SA4, another rechargeable battery 12 _{m + 1} waiting to be discharged is replaced with the rechargeable battery 12 _m at SA4. Is connected to the input terminal 24 of the DC voltage conversion circuit 28, and the DC voltage conversion circuit 28 discharges the rechargeable battery 12 _{m + 1} and the rechargeable battery 1
2 _liters of charging is done. At the same time, in SA4, the content of the discharging flag F _D of the rechargeable battery 12 _{m + 1} is “1”.
And other status flags F _DW , F _CW , F _C , F
The content of _F is cleared to "0". If there is no other rechargeable battery waiting to be discharged, the determination at SA3 is negative, so at SA5, the rechargeable battery 12 _l being charged is connected to the charging circuit 32 and the rechargeable battery 12 _l continues to be charged. To be done.

Further, when the charging of the rechargeable battery 12 _l is completed earlier in the process of continuing the discharging of the rechargeable battery 12 _m and the charging of the rechargeable battery 12 _l by the DC voltage conversion circuit 28, the determination of SA1 is made. Since the determination is negative and the determination in SA6 is affirmative, it is determined in SA7 whether or not there is another rechargeable battery waiting to be charged. If the determination at SA7 is affirmative, and if the other rechargeable battery waiting to be charged is, for example, 12 _{l + 1} , then SA8 is executed to replace the rechargeable battery 12 _l and wait for another rechargeable battery. The rechargeable battery 12 _{l + 1} is connected to the output terminal 26 of the DC voltage conversion circuit 28, and the DC voltage conversion circuit 28 discharges the rechargeable battery 12 _m and recharges the battery 1.
2 _{l + 1} charging is performed. At the same time, in SA8, the content of the charging flag F _C of the rechargeable battery 12 _{l + 1} is “1”.
, And other status flags F _DW , F _CW , F _D , F
The content of _F is cleared to "0". If there is no other rechargeable battery waiting to be charged, the determination at SA7 is negative, so at SA9, the rechargeable battery 12 _m being discharged is connected to the discharge circuit 22 and the rechargeable battery 12 _m continues to be discharged. To be done.

In FIGS. 7 and 8, SA4 and SA13 correspond to the discharge determining means 96, and SA8 and
SA12 and SA15 are the means 100 for determining during charging.
It corresponds to. Further, in SA4, SA12, and SA13, the discharging indicator lamp 44 _D at the connection location of the corresponding rechargeable battery is turned on, and the SA8 and SA8 are displayed.
In 15, since the charging indicator lamp 44 _C at the connection location of the corresponding rechargeable battery is turned on, those SA4, S
A12, SA13, SA8, and SA15 also correspond to the display control means 106.

[0040] As described above, according to this embodiment, the rechargeable battery of the plurality of rechargeable battery 12 ₁ ... 12 undischarged i.e. discharge waiting rechargeable battery within the _n 12 _m and discharge spent i.e. charge waiting 12 If there is _l, the rechargeable battery 12 _m waiting to be discharged is connected to the input terminal of the DC voltage conversion circuit 28, and the rechargeable battery 12 _l waiting to be charged is connected to the DC voltage conversion circuit 2
8 is connected to the output side. That is, the uncharged rechargeable battery 12
_By charging the discharged rechargeable battery 12 _l with the electric energy remaining in _m , the undischarged rechargeable battery 12 _l
At the same time when _m is discharged, the rechargeable battery 12 _l
Is charged. Therefore, according to the present embodiment, the electric energy remaining in the used rechargeable battery 12 _m , which has been wasted in the past, is effectively used for charging the other rechargeable batteries, resulting in high energy efficiency. can get.

Further, according to the embodiment, an undischarged rechargeable battery 1
Since the rechargeable battery 12 _l that has been discharged is charged at the same time as the discharge of 2 _m , the discharge time is not necessary as compared with the case where the rechargeable batteries are individually discharged and then charged, and the charging efficiency is substantially improved. .

Further, in the charging device 10 of the present embodiment, when there are rechargeable batteries 12 _l waiting to be charged among a plurality of rechargeable batteries 12 ₁ ... 12 _n , but there is no rechargeable battery 12 _m waiting to be discharged. , Is connected to the output side of the charging circuit 32 to charge the rechargeable battery 12 _l waiting to be charged. As described above, when there is no undischarged rechargeable battery among the plurality of rechargeable batteries 12 ₁ ... 12 _n connected to the charging device 10, the discharged rechargeable battery 12 _{l to be} charged is Is automatically connected to the output side of the charging circuit 32, there is an advantage that the rechargeable battery 12 _l to be charged is charged without waiting for the connection of the undischarged rechargeable battery.

[0043] Also, in the charging apparatus 10 of the present embodiment, with the discharge circuit 22 is provided for discharging the rechargeable battery 12 _m of undischarged of said plurality of rechargeable battery 12 ₁ · · 12 _n, they When the discharged rechargeable battery 12 _l does not exist among the plurality of rechargeable batteries 12 ₁ ... 12 _n , the discharge circuit 22 for discharging the undischarged rechargeable battery 12 _m.
Is configured to connect to. In this way, the charging device 1
If there is no discharged rechargeable battery among the plurality of rechargeable batteries 12 ₁ ··· 12 _n connected to 0, the already connected undischarged rechargeable battery 12 _m is discharged by the discharge circuit 22. Therefore, there is an advantage that a fully charged rechargeable battery is automatically prepared.

Further, the charging device 10 of the present embodiment is provided with a charging completion lamp 44 _F for indicating that the plurality of rechargeable batteries 12 ₁ ... 12 _n are in a charged state, respectively. When the charging completion determining means 102 determines that the individual rechargeable batteries 12 ₁ ... 12 _n are in the charged state, the charging completion lamp 44 corresponding to the rechargeable battery determined to be in the charged state. _F is the display control means 106
Since it is lit up by a plurality of rechargeable batteries 12 ₁ ··· 12 _n
It becomes clear which one of them is in the charging completed state,
There is an advantage that accidental reuse of an uncharged rechargeable battery is prevented.

Further, according to this embodiment, the rechargeable battery 12 _n charge completion of the plurality of battery 12 ₁ · · 12 _n
Since the charging current I _C for the battery is set to zero, there is an advantage that overcharging is prevented and the battery life is maintained.

Next, another embodiment of the present invention will be described. In the following description, the same parts as those in the above-described embodiment will be designated by the same reference numerals and the description thereof will be omitted. FIG. 10 shows the external shape of the charging device 110 of this embodiment.
Shows its electrical configuration, and FIG. 12 is a flow chart showing its operation.

[0047] In FIG. 10, the charging device 110, a pair that is connected to the rechargeable battery 12 _n input terminals 24a and 2
An input connection locations 112 having 4b, a output connection locations 114 having a pair of output terminals 26a and 26b connected to the rechargeable battery 12 _n are provided. Charger 1
As shown in FIG.
8 and the charging current I output from the DC voltage conversion circuit 28
Control circuit 116 for controlling _C to be constant, and input side connection display lamp 1 driven by this control circuit 116
18, an output side connection display lamp 120, and a charging completion display lamp 122 are provided.

The control circuit 116 is the control circuit of the above-mentioned embodiment.
The configuration is similar to that of the control circuit 42, but the flow of FIG.
Operates according to the chart. That is, in SB1,
The discharge waiting state or the discharge connected to the power side connection place 112
Rechargeable battery 12_nVoltage V _BATinIs the preset format
Reference value V₁Is greater than or equal to. This format
Reference value V₁Is a rechargeable battery 12 in a discharge waiting state or during discharging
_nIs connected to the input side connection place 112
Is for the purpose of, for example, 0.8V per
Can be If the above judgment of SB1 is denied, it will wait.
However, if it is affirmed, it will be entered at SB2.
The power side connection indicator lamp 118 is turned on.

At SB3, it is determined whether or not the voltage V _BATout of the rechargeable battery 12 _n connected to the output side connection location 114 in the charging waiting state or being charged is larger than a preset determination reference value V _2. It This judgment reference value V ₂ is determined by the rechargeable battery 12 _n being charged or being charged in the output side connection place 1
It is for determining whether or not it is connected to 14,
For example, 1.0 V is used for each. SB3 above
If the determination is NO, the above SB1 and subsequent steps are repeatedly executed, but if the determination is YES, the output side connection display lamp 120 is lit at SA4.

Next, at SB5, the charging current I_CIn advance
The control circuit 11 is configured to match the set target value.
Since the current command signal SI is output from 6, output side connection
Rechargeable battery 12 connected to location 114_nIs charged by a constant current
Be charged. Then, it is determined whether or not the charging is completed in SB6.
Rechargeable battery 12 connected to the output side connection place 114 _n
Voltage V_BAToutIs a predetermined value ΔV from the peak value₁Only
It is judged based on whether or not it has decreased. This SB6 format
If the disconnection is denied, SB1 and below are repeatedly executed.
To be done.

However, if the determination at SB6 is affirmative, after the current command signal SI is output from the control circuit 116 so that the charging current I _C becomes zero at SB7, S
At B8, the charging completion indicator lamp 122 is turned on.

According to this embodiment, the input side connection place 112
By charging the rechargeable battery 12 _n of connected undischarged connected discharged already on the output side connection location 114 using electrical energy remaining in the battery 12 _n, the battery of the undischarged 12 At the same time as _n is discharged, the discharged rechargeable battery 12 _n is charged. Therefore, since the electric energy remaining in the used rechargeable battery, which has been wasted in the past, is effectively used for charging the other rechargeable batteries, high energy efficiency can be obtained. Further, since the uncharged rechargeable battery 12 _n is discharged and the discharged rechargeable battery 12 _n is charged at the same time, the discharging time is not required as compared with the case where the rechargeable batteries 12 _n are individually discharged and then charged. There is an advantage that the charging efficiency is improved.

Further, according to the present embodiment, when the charging of the rechargeable battery 12 _n connected to the output side connection location 114 is completed, the charging current I _C for the rechargeable battery 12 _n becomes zero, so that overcharging is prevented. It has the advantage of being prevented and maintaining battery life. In addition, the rechargeable battery 1 connected to the output side connection place 114
When the charging of 2 _n is completed, the charging completion indicator lamp 122 is turned on, so that there is an advantage that the replacement can be efficiently performed.

Although one embodiment of the present invention has been described above with reference to the drawings, the present invention can be applied to other modes.

For example, in the above-described charging device 10 shown in FIG. 1, even if the charging circuit 32 is removed, a temporary effect can be obtained.

Further, in the above-mentioned embodiment, the output terminal 2
The rechargeable battery 12 _m connected to the output terminal 26 within the current cutoff period is provided with a constant current cutoff period for a constant charging current I _C flowing through the rechargeable battery 12 _m connected to
The charging voltage V _C may be detected.

Further, in the above-mentioned embodiment, the above-mentioned FIG.
In the DC voltage conversion circuit 28, the input voltage detection circuit 5
8 and the output voltage detection circuit 62 are composed of a voltage dividing circuit, but may directly detect the voltage of the input terminal 24 and the output terminal 26.

Further, in the flowcharts of FIGS. 7 and 8 described above, SA7 and SA8 or SA11 and SA12 correspond to an extremely rare situation, and therefore may be removed.

The above description is merely one embodiment of the present invention, and the present invention can be variously modified without departing from the spirit of the invention.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a circuit configuration of a charging device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram illustrating a configuration of a discharge circuit of FIG.

3 is a circuit diagram illustrating a configuration of the DC voltage conversion circuit of FIG.

FIG. 4 is a circuit diagram illustrating a configuration of a charging circuit of FIG.

5 is a functional block diagram illustrating a main part of a control function of the control circuit of FIG.

6 is a flowchart illustrating a main part of control operation of the control circuit of FIG. 1, and is a diagram illustrating an interrupt routine.

7 is a flowchart illustrating a main part of control operation of the control circuit of FIG. 1, and is a diagram illustrating a part of a switching control routine.

8 is a flowchart illustrating a main part of control operation of the control circuit of FIG. 1, and is a diagram illustrating a part of a switching control routine.

9 is a diagram showing a voltage change in a charging process by constant current charging of the rechargeable battery of FIG.

FIG. 10 is a perspective view showing a charging device according to another embodiment of the present invention.

11 is a diagram illustrating a circuit configuration of the embodiment of FIG.

12 is a flowchart illustrating a main part of control operation of the control circuit of FIG.

[Explanation of symbols]

 10: Charging device 12: Rechargeable battery 22: Discharge circuit 28: DC voltage conversion circuit 32: Charging circuit 90: Selective connection means 92: Control means 94: Discharge wait determination means 96: Discharging in-wait determination means 98: Charge wait determination means 100 : Charging determination means 102: Charging completion determination means 104: Charging completion display means 106: Display control means

Claims (5)

[Claims] 1. A plurality of undischarged rechargeable batteries are sequentially discharged,
A charging method for successively charging the discharged rechargeable battery after that, by charging the discharged rechargeable battery using the electric energy remaining in the undischarged rechargeable battery, the undischarged A charging method comprising discharging a rechargeable battery and charging the discharged rechargeable battery at the same time. 2. A charging device connected to charge a plurality of rechargeable batteries, the charging circuit outputting a charging voltage for charging the rechargeable batteries, and a direct current input from an input terminal. A DC voltage conversion circuit for converting the voltage into a charging voltage and outputting the charging voltage, a selective connection means for selectively connecting the plurality of rechargeable batteries to the charging circuit and the DC voltage conversion circuit, respectively, Control means for connecting an undischarged rechargeable battery among them to a power input terminal of the DC voltage conversion circuit and connecting a discharged rechargeable battery among the plurality of rechargeable batteries to the output side of the DC voltage conversion circuit. A charging device comprising: 3. The control means connects the output side of the charging circuit to charge the discharged rechargeable battery when there is no undischarged rechargeable battery among the plurality of rechargeable batteries. The charging device according to claim 2, which is a battery. 4. A discharge circuit for discharging an undischarged rechargeable battery among the plurality of rechargeable batteries is provided, and the selective connecting means selectively selects the plurality of rechargeable batteries also in the discharge circuit. When there is no discharged rechargeable battery among the plurality of rechargeable batteries, the control means is connected to the discharge circuit in order to discharge the undischarged rechargeable battery. The charging device according to claim 2 or 3. 5. A charging completion display means for displaying that the plurality of rechargeable batteries are in a charged state is provided, and the control means is in a state in which the plurality of rechargeable batteries are in a charged state. 5. A charging completion judging means for judging whether or not it is further included, and a display control means for displaying a charging completion display means corresponding to the rechargeable battery judged to be in a charged state. Charging device.