JP2000116013A - Electronic equipment and method for estimating capacity of secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To estimate the capacity of a secondary battery charged by considering the influence of internal resistance or deterioration with a simple configuration. SOLUTION: A secondary battery 220 is charged intermittently, a battery voltage detection circuit 281 detects a voltage Evc of the secondary battery 220 during charging, and a voltage Vvd when a certain amount of time passes after charging is interrupted. Further, a current detection circuit 291 detects the charging current Eic, subtracts the voltage Evd from the voltage Ecv to obtain a voltage increase ΔEv, and furthermore detects internal resistance R3 of the secondary battery 220 from the voltage increase ΔEv and the charging current ΔEic for converting to a battery capacity by referring to one conversion table 285-x (X:1-n) corresponding to the internal resistance Re.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for estimating the capacity of an electronic device and a secondary battery, and more particularly to a method of estimating the capacity of a charged secondary battery with a simple configuration. It relates to an estimation method.

[0002]

2. Description of the Related Art In recent years, small portable electronic devices such as portable terminals and electronic watches have been housed in charging devices called stations, and data transfer and the like have been performed along with charging of the portable electronic devices. Here, if charging and data transfer are performed via electrical contacts, these contacts are exposed, which causes a problem in terms of waterproofness. For this reason, it is desirable that charging, signal transfer, and the like be performed in a non-contact manner by electromagnetic coupling of coils provided in both the station and the portable electronic device.

In such a configuration, when a high frequency signal is applied to the coil on the station side, an external magnetic field is generated, and an induced voltage is generated on the coil on the portable electronic device side. By rectifying the induced voltage with a diode or the like, it becomes possible to contactlessly charge a secondary battery built in the portable electronic device. Also, the electromagnetic coupling between the two coils makes it possible to transfer signals bidirectionally from the station to the portable electronic device or from the portable electronic device to the station in a non-contact manner.

[0004]

In the case where the secondary battery is charged to a desired capacity, performing the charging operation beyond the capacity is unnecessary consumption of power and is uneconomical. Further, when charging is performed at a rated capacity or more, there is a possibility that liquid leakage or the like may occur. Therefore, in charging the secondary battery, a configuration in which charging control is performed according to the capacity of the secondary battery is desirable. As a configuration for this,
It is conceivable to estimate the capacity of the secondary battery from the terminal voltage of the secondary battery during charging.

[0005] However, for example, just because the terminal voltage of the secondary battery becomes almost equal to the charging voltage does not necessarily mean that the battery is charged to near the rated capacity. In addition, the terminal voltage of the secondary battery during charging rises due to its internal resistance (see FIG. 24), and does not indicate a true secondary voltage. Furthermore, the internal resistance Re of the secondary battery
23, as shown in FIG. 23, becomes larger as the storage temperature is higher due to thermal decomposition of the electrolytic solution. For example, ambient temperature 60
When stored at [° C.], thermal decomposition proceeds faster than when stored at 25 ° C., and during the same storage period, the internal resistance Re of the secondary battery increases. .
Furthermore, even with the same secondary battery, the internal resistance Re
Has a temperature characteristic as shown in FIG. 23, and if the use environment is different, the internal resistance Re is different. For these reasons, it has been difficult to accurately estimate the capacity from the terminal voltage of the secondary battery during charging. Therefore, an object of the present invention is to accurately estimate the capacity of a charged secondary battery with a simple configuration while reducing the influence of changes in the internal resistance of the secondary battery or deterioration of the secondary battery. Another object of the present invention is to provide a simple electronic device and a method for estimating the capacity of a secondary battery.

[0006]

In order to solve the above-mentioned problems, a configuration according to a first aspect of the present invention comprises a charging means for intermittently charging a secondary battery, and a charging means which is a current flowing through the secondary battery during the charging. Current detection means for detecting an hour current, and interruption voltage detection means for detecting an interruption voltage which is a voltage of the secondary battery at a point in time when a predetermined time has elapsed after charging by the charging means is interrupted, A charging voltage detecting means for detecting a charging voltage which is a voltage of the secondary battery when charging is being performed by the charging means; and calculating a difference voltage by subtracting the charging voltage from the interruption voltage. Subtraction means, internal resistance calculation means for calculating the internal resistance of the secondary battery based on the difference voltage and the charging current, and estimation of the capacity of the secondary battery based on the difference voltage and the internal resistance Is characterized by comprising a that estimating means.

According to a second aspect of the present invention, there is provided a charging means for intermittently charging a secondary battery, and the charging means for intermittently charging the secondary battery when a predetermined first predetermined time has elapsed since the charging by the charging means was interrupted. An interruption voltage detecting means for detecting an interruption voltage which is a voltage of a battery, and a charging voltage detecting means for detecting a charging voltage which is a voltage of the secondary battery when the charging is performed by the charging means. Subtracting means for subtracting the charging voltage from the interruption voltage to calculate a difference voltage, and connecting a discharging resistor having a predetermined resistance value determined in advance after detecting the interruption voltage in parallel with the secondary battery. A resistor connection means for detecting the voltage of the secondary battery at the time when a second predetermined time has elapsed since the connection of the discharge resistor, and a voltage detection means for detecting the voltage after the resistance connection. ,Previous Internal resistance calculating means for calculating the internal resistance of the secondary battery from the voltage at the time of interruption, the voltage after connection of the resistance, and the resistance value, and estimation for estimating the capacity of the secondary battery based on the difference voltage and the internal resistance. Means.

According to a third aspect of the present invention, a charging means for intermittently charging the secondary battery and a discharging resistor having a predetermined resistance value when charging by the charging means is interrupted are connected to the secondary battery. A resistor connection unit connected in parallel, a first predetermined time before the interruption of charging by the charging unit, a lapse of the first predetermined time from the restart of charging by the charging unit, or the charging unit A charging voltage detecting means for detecting a charging voltage which is a voltage of the secondary battery at any one time after the elapse of the first predetermined time since the charging was interrupted; and A post-resistor connection voltage detecting means for detecting a post-resistor connection voltage which is a voltage of the secondary battery at a time when a predetermined second predetermined time has elapsed, and subtracting the resistor connection voltage from the charging voltage voltage to obtain a difference. Voltage Subtraction means for calculating; internal resistance calculation means for calculating the internal resistance of the secondary battery from the difference voltage and the resistance value; and estimation for estimating the capacity of the secondary battery based on the difference voltage and the internal resistance. Means.

According to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, a temperature detection for detecting a temperature of the secondary battery or a temperature around the secondary battery is installed. And temperature correction means for correcting the internal resistance calculated by the internal resistance calculation means based on the detected temperature.

According to a fifth aspect of the present invention, in the configuration of the first aspect, a true voltage calculation for calculating a true voltage of the secondary battery based on the interruption voltage, the charging current, and the internal resistance. Means, and charging voltage control means for controlling a voltage at the time of constant voltage charging in the charging means, and controlling the voltage at the time of constant voltage charging so that the true battery voltage does not exceed a predetermined reference value. It is characterized by doing.

According to a sixth aspect of the present invention, in the configuration according to any one of the first to fifth aspects, based on the calculated internal resistance of the secondary battery, the charge interruption period in the charging means is set. It is characterized by comprising a charge interruption period control means for controlling.

According to a seventh aspect of the present invention, in the configuration of the sixth aspect, the charging interruption period control means sets the interruption period longer as the internal resistance of the secondary battery increases. And

According to an eighth aspect of the present invention, in the configuration according to any one of the first to seventh aspects, a full charge timer means for managing a charging time for performing a full charge of the secondary battery is provided. And timer control means for controlling the full charge timer means based on the calculation result of the internal resistance.

According to a ninth aspect of the present invention, in the configuration according to any one of the first to eighth aspects, a degree of deterioration of the secondary battery is calculated based on a calculation result of the internal resistance. It is characterized by having means.

According to a tenth aspect of the present invention, in the configuration of the ninth aspect, there is provided a deterioration degree display means for displaying the calculated degree of deterioration.

According to an eleventh aspect of the present invention, in the configuration of any one of the first to tenth aspects, it is possible to determine whether or not the calculated internal resistance exceeds a predetermined reference internal resistance value. It is characterized by having a degree discriminating means.

According to a twelfth aspect of the present invention, in the configuration of the eleventh aspect, there is provided a deterioration judgment result display means for displaying a judgment result of the deterioration degree judgment means.

In a preferred embodiment of the present invention, a charging step for intermittently charging the secondary battery, a current detecting step for detecting a charging current that is a current flowing through the secondary battery during the charging, and the charging step An interruption voltage detection step of detecting an interruption voltage that is a voltage of the secondary battery at a point in time when a predetermined time has elapsed since the interruption of the charging in the charging step. A charging voltage detection step of detecting a charging voltage that is a voltage of the secondary battery; a subtraction step of subtracting the charging voltage voltage from the interruption voltage to calculate a difference voltage; and the difference voltage and the charging current. , An internal resistance calculating step of calculating the internal resistance of the secondary battery, and an estimating step of estimating the capacity of the secondary battery based on the difference voltage and the internal resistance. It is characterized.

According to a fourteenth aspect of the present invention, there is provided a charging step for intermittently charging a secondary battery, and the secondary battery at a point in time when a predetermined first predetermined time has elapsed since the charging in the charging step was interrupted. An interruption voltage detection step of detecting an interruption voltage that is a voltage of a battery, and a charging voltage detection step of detecting a charging voltage that is a voltage of the secondary battery when charging is performed in the charging step. Subtracting the voltage during charging from the voltage during interruption to calculate a difference voltage, and a discharge resistor having a predetermined resistance value determined in advance after the detection of the interruption voltage in parallel with the secondary battery. A resistor connection step for connecting, and a resistor connection voltage detection step for detecting a voltage after the resistor connection, which is a voltage of the secondary battery at a point in time when a predetermined second predetermined time has elapsed since the connection of the discharge resistor. An interrupting voltage, an internal resistance calculating step of calculating an internal resistance of the secondary battery from the voltage after connection of the resistance and the resistance value, and a capacity of the secondary battery based on the difference voltage and the internal resistance. And an estimating step of estimating.

According to a fifteenth aspect of the present invention, a charging step of intermittently charging the secondary battery and a discharging resistor having a predetermined resistance value which is predetermined when the charging is interrupted in the charging step are connected to the secondary battery. A resistor connection step of connecting in parallel, a predetermined first predetermined time before the interruption of the charging in the charging step, a lapse of the first predetermined time from the restart of the charging in the charging step, or the charging step A charging voltage detection step of detecting a charging voltage that is a voltage of the secondary battery at any one time after the elapse of the first predetermined time since the charging was interrupted, and A post-resistor connection voltage detection step of detecting a post-resistor connection voltage that is a voltage of the secondary battery at a time when a predetermined second predetermined time has elapsed, and subtracting the resistor connection voltage from the charging voltage. A subtraction step of calculating a voltage; an internal resistance calculation step of calculating an internal resistance of the secondary battery from the difference voltage and the resistance value; and a capacity estimation of the secondary battery based on the difference voltage and the internal resistance. Estimating process,
It is characterized by having.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the drawings. [1] Determination of Charging Time First, a method of determining a charging time will be briefly described. FIG. 1 shows charge / discharge characteristics of a general secondary battery. As shown in FIG. 1, the terminal voltage of the secondary battery during charging is almost constant. Further, the terminal voltage of the secondary battery at the time of charging does not show a true value (= true voltage Evd of the secondary battery) as described above. This will be described with reference to FIG. Generally, a secondary battery has an internal resistance R
Therefore, at the time of charging, a voltage Evc obtained by adding the product of the internal resistance Re and the charging current Ei of the secondary battery to the voltage Evd of the true secondary battery is detected. .

Here, the case where the secondary battery is charged at a constant voltage E will be considered. In this case, the charging current Ei is represented by the following equation. Ei = (E−Evc) / R Here, R in this equation is a resistance associated with constant voltage charging.

Next, as the charging of the secondary battery proceeds, the terminal voltage Evc of the secondary battery approaches the constant voltage E, so that the charging current Ei gradually decreases. For this reason, the voltage rise of the secondary battery (the voltage drop when focusing on the transition from the charge to the discharge) represented by the product of the internal resistance Re and the charge current Ei when the transition from the discharge to the charge is made. Become smaller. Therefore, by detecting the voltage rise of the secondary battery, it is possible to indirectly estimate the capacity charged in the secondary battery. Here, in order to detect an increase in the voltage of the secondary battery, the charging is performed intermittently, and the secondary battery in a case where a certain period of time has elapsed since the charging was interrupted from the voltage of the secondary battery at the time of charging. Is obtained by subtracting the voltage of

On the other hand, in FIG. 1, a case will be examined in which the battery is discharged at a constant rate by connecting 1 kΩ to both terminals of the secondary battery. When the battery capacity is reduced in this way, the terminal voltage of the secondary battery decreases almost linearly as shown in the figure. This indicates that the capacity of the secondary battery corresponds to the terminal voltage at the time of discharging. Therefore, the capacity F of the secondary battery can be expressed as a function F (v) having the terminal voltage v as an argument. For this reason, while the function F (v) is tabulated or expressed as a mathematical expression in advance, charging is performed intermittently, and the terminal voltage value Ev at the time of interruption is substituted into the function F (Ev) to obtain the function F (Ev) at that time. The capacity of the secondary battery can be estimated.

[2] First Embodiment Next, a first embodiment of the present invention will be described more specifically. In the first embodiment, a station will be described as an example of a charging device, and an electronic device will be described as an example of a device to be charged.

[2.1] Mechanical Configuration of First Embodiment FIG. 3 is a plan view showing the configuration of a station and an electronic timepiece according to the first embodiment. As shown in FIG. 3, the electronic timepiece 200 is housed in the recess 101 of the station 100 when performing charging, data transfer, or the like. This recess 1
01 is the main body 201 of the electronic timepiece 200 and the band 20
Since the watch main body 201 is formed in a shape slightly larger than 2, the watch main body 201 is housed in a state of being positioned with respect to the station 100. The station 100 has a charge start button 103 for instructing the start of charging.
₁ and, together with various input unit such as a transfer start button 103 ₂ for instructing the start of data transfer, the display unit 104 for performing various displays are provided. Note that the electronic timepiece 200 according to the present embodiment is worn on the user's arm in a normal use state, and it is needless to say that the date and time and the like are displayed on the display unit 204. It is configured to detect and store biological information such as heart rate at regular intervals.

FIG. 4 is a sectional view taken along line AA in FIG. As shown in FIG. 4, a watch side coil 210 for data transfer and charging is provided on a lower back cover 212 of the main body 201 of the electronic timepiece via a cover glass 211. Further, the watch main body 201 is provided with a circuit board 221 connected to the secondary battery 220, the watch side coil 210, and the like. On the other hand, a station-side coil 110 is provided at a position facing the clock-side coil 210 in the recess 101 of the station 100 via a cover glass 111. The station 100 includes a coil 110,
A circuit board 121 connected to a charge start button 103 ₁ , a transfer start button 103 ₂ , a display unit 104, a primary power supply (not shown), and the like is provided.

As described above, when the electronic timepiece 200 is housed in the station 100, the station-side coil 110 and the clock-side coil 210 are
Although they are physically non-contacted by 11 and 211, they are electromagnetically coupled because the coil winding surfaces are substantially parallel. The station-side coil 110 and the clock-side coil 210 are air cores that do not have a magnetic core for reasons such as avoiding magnetization of the clock mechanism, avoiding weight increase on the clock side, and avoiding exposure of magnetic metal. It is a type.
Therefore, when the present invention is applied to an electronic device in which such a problem is not a problem, a coil having a magnetic core can be employed. However, if the signal frequency given to the coil is sufficiently high, the air-core type is sufficient.

[2.2] Electrical Configuration of First Embodiment Next, the electrical configurations of the station 100 and the electronic timepiece 200 will be described. [2.2.1] Configuration of Station First, for convenience of description, the configuration of the station 100 that charges the electronic timepiece 200 will be described with reference to FIG. One terminal of the station side coil 110 is shown in FIG.
, The other terminal D is connected to the drain of the transistor 153 while being pulled up to the power supply voltage Vcc. In this case, the transistor 15
The gate of the transistor 153 is connected to the output of the AND gate 152 which receives the clock signal CLK at one input terminal, while the source of the transistor 153 is grounded. Here, the clock signal CLK is a signal for synchronizing the operation of each unit, and is generated by the oscillation circuit 140.

Now, when the charge start button 103 ₁ and the transfer start button 103 ₂ are pressed by the user,
Each outputs a one-shot pulse signal. Here, the pulse signals output by both buttons, for convenience of explanation, the case will be the STR collectively, to distinguish whether any button is pressed, the charging start button 103 ₁ is pressed Is assumed to output a pulse signal CS. Next, when the timer A141 receives the supply of the pulse signal STR, the timer A141 counts down the preset value m with the clock signal CLK, and outputs a signal a which becomes "H" level during the counting operation. For example,
If the preset value m is set to a value such that the "H" level period of the signal a is 10 hours, the timer A1
41, so that the output a signal a from the charging start button 103 ₁ or the transfer start button 103 ₂ by the user is pressed of 10 hours only "H" level. The level of the signal a is inverted by the inverting circuit 143 and supplied to the second input terminal of the OR gate 157 and the processing circuit 130.

The timer B142 is provided with a pulse signal ST
R, the preset value n is changed to the clock signal C
LK counts down and during the counting operation,
A signal “b” which becomes “H” level is output. Here, the preset value n is set to be sufficiently smaller than m. For example, when the “H” level period of the signal b is set to 30 minutes, the timer B 142 after one of the charging start button 103 ₁ or the transfer start button 103 ₂ is depressed by the user, and to output a signal b which becomes 30 minutes only "H" level.

Here, the time set by the timer A141 is a time necessary and sufficient to charge the battery to a capacity corresponding to a full charge state. Therefore, the charge start button 103
_{After 1} or the transfer start button 103 ₂ is depressed, for some reason, even if a later-described command com3 for ending charging is not sent from the electronic timepiece 200, it is possible to terminate the charging. Also, the timer B1
The set time by 42 is a time required for charging from a state where the battery capacity is zero to a state where data transfer is possible (system start state), and is set to determine the following state. The electronic timepiece 200 is housed in the station 100, but the battery capacity is insufficient, so that the data transfer is not possible. The electronic timepiece 200 is not housed in the station 100.

Next, after receiving the supply of the pulse signal STR, the command detector 160 receives a later-described command com1 or command com3 from the electronic timepiece 200 for a certain period during which the signal b becomes the “H” level. If it is not, a signal d which becomes "H" level is output.
The signal d is supplied to the first input terminal of the OR gate 157 and the processing circuit 130. The detailed configuration of the command detector 160 will be described later.

After receiving the supply of the pulse signal STR, the charge / transfer switch 170 changes the signal OFF to "L".
During the level period, the first charging signal as shown in FIG. 6A is output as a pulse signal e. In addition to this, the charge / transfer switch 170 is provided with a charge start button 10.
3 ₁ is supplied with the pulse signal CS by is pressed, and a command co, which will be described later, from the electronic timepiece 200
When m1 is received and the signal com1 is supplied, as shown in FIG. 6B, the second charging signal having the increased duty ratio is output as the signal e. However, charging /
When the signal OFF transitions to the “H” level, the transfer switch 170 holds the signal e at the “L” level.

By the charge / transfer switch 170, the transistor 153 receives the supply of the pulse signal STR, and during the period when the signal e is at the "H" level,
The switching between the drain and the source is performed according to the level of the clock signal CLK. For this reason,
Since a pulse signal obtained by switching the power supply voltage Vcc with the clock signal CLK is applied to the station-side coil 110, an external magnetic field is generated. In the electronic timepiece 200, a signal induced in the timepiece coil 210 by the external magnetic field is rectified and the secondary battery 220 is charged, as described later. On the other hand, when the signal e is at the “L” level, the AND gate 152
Is also at the “L” level, and the transistor 153 is turned off (open).
, No pulse signal is applied. Therefore, no external magnetic field is generated, and the secondary battery 220 of the electronic timepiece 200 is not charged. Therefore, the charging of the secondary battery 220 is performed intermittently according to the level of the signal e.

During the "L" level period of the signal e, the output of the AND gate 152 also becomes "L" level,
Since the transistor 153 is turned off (open), the station-side coil 110 is pulled up by the power supply voltage Vcc. In this state, when an external magnetic field is generated by the clock-side coil 210, a signal S2 is induced at the terminal D of the station-side coil 110. The signal S2 is supplied to the receiving circuit 154, and the receiving circuit 154 demodulates the signal S2 using the clock signal CLK. The detailed configuration of the receiving circuit 154 will be described later. Next, the decoder 155 operates during the period when the signal e is at the “L” level.
4 decodes the demodulation result. Therefore, the signal e
Is high while the electronic timepiece 200 is charged, while data is transferred while the signal e is low. Therefore, the charge / transfer switch 170 switches between the charging process and the data transfer process according to the level of the signal e.

The signal from the electronic timepiece 200 is not only a command com1 or a command com3 described later but also biological information (data) such as a pulse rate and a heart rate. The decoder 155 is a processing circuit for the biological information. On the other hand, while receiving the command com1 or com3, each of the units is notified by setting the output signals com1 and com3 to the “H” level. The OR gate 156 controls each signal com1
And the logical sum of com3 and com3 is output as a signal c. Therefore, the signal c is transmitted from the electronic timepiece 200 as a command.
This indicates that either the com1 or the command com3 is being received. Also, if the decoding result is the command co
The signal com1 indicating m1 is a charge / transfer switch 17
0 is supplied. On the other hand, the decoding result
The signal com3 indicating m3 is supplied to the third input terminal of the OR gate 157. And OR gate 157
The logical sum of the charge / transfer switch 17 is set to the signal OFF.
0 is supplied.

Here, the signals supplied to the first to third input terminals of the OR gate 157 correspond to the command detector 1 respectively.
60, a signal obtained by inverting the level of the signal a of the timer A141, and a signal com3 indicating that the decoding result is the command com3.
Holds the signal e at the "L" level in any of the following cases. That is, there are the following three cases where the charge / transfer switch 170 holds the signal e at the “L” level to terminate the charging. Charge start button 103 ₁ or transfer start button 1
03 ₂ is output is depressed the signal STR until after a period of 30 minutes, a command from the electronic timepiece 200
If you do not receive com1 or com3, 10 hours have passed since charging started,
When the signal received from the electronic timepiece 200 is the command com3.

The processing circuit 130 displays various kinds of display such as an input signal and decoded biological information on the display unit 1.
04.

[2.2.2] Command Detector Next, the configuration of the command detector 160 will be described with reference to FIG. First, the AND gate 1601 outputs the signal b
And the logical product of the signals c. Next, NOR gate 1
The RS flip-flop composed of 603 and 1604 inputs the AND of the AND gate 1601 as an R signal and inputs the signal STR as an S signal. The inverter circuit 1605 inverts the output of the NOR gate 1604 and outputs the inverted signal as the signal U1.
Is supplied to the D input terminal. This D flip-flop 160
6 is reset by the signal STR and outputs the level of the input terminal D immediately before the falling of the signal b as the signal d.

Now, the user inputs the charge start button 10
When 3 ₁ or the transfer start button 103 ₂ is depressed, for example, one-shot pulse signal STR is output, as shown in FIG. 8 (a). The signal STR causes the output of the NOR gate 1604 to go to the "L" level, so that the signal U1 goes to the "H" level and the timer B142 (FIG. 5).
8) performs the counting operation, so that the signal b becomes the “H” level for 30 minutes as shown in FIG. 8A.

[2.2.2.1] Operation when Command is Received Here, the decoder 155 in FIG.
, The command com1 or the command com3 is received in a pulsed manner during a period when the signal e is at the “L” level. In such a case, when signal b and signal c both attain an "H" level and the logical product thereof attains an "H" level, NOR gate 1
Since the output of 604 goes to the "H" level, the signal U1 transitions to the "L" level, and this state is maintained thereafter.
Therefore, when the signal b falls 30 minutes after the one-shot pulse signal STR is output (precisely, immediately before), the D flip-flop 1606
, The signal d output from the output terminal Q remains at the “L” level.

[2.2.2.2] Operation when Command Not Received On the other hand, the decoder 155
If m1 or command com3 is not received, signal c is
As shown in FIG. 8B, it remains at the “L” level. Therefore, since the signal U1 is held at the “H” level, the signal b is output 30 minutes after the signal STR is output.
At the time when the D flip-flop 16
The signal d output from the output terminal Q of the signal 06 changes to the “H” level.

[2.2.2.3] Summary of Operation of Command Detector As described above, the command detector 160 outputs the pulse signal ST
During a certain period from the supply of R until a lapse of 30 minutes, at least the command com1 is issued from the electronic timepiece 200 side.
Alternatively, if the command com3 is received, the signal d is changed to the “H” level after the elapse of the period, while if no command is received, the signal d is held at the “L” level.

[2.2.3] Receiving Circuit Next, the configuration of the receiving circuit 154 will be described with reference to FIG. Note that the configuration of the receiving circuit 154 is merely an example, and is originally determined by a modulation method in data transfer. First, as shown in FIG. 9, the signal S2 induced at the other terminal D of the station-side coil 110 is connected to the inverter circuit 154.
The level is inverted by 1 and the waveform is shaped.
It is supplied as a reset signal RST of D flip-flops 1542 and 1543 synchronized with the clock signal CLK of the oscillation circuit 140 (see FIG. 3). Here, input terminal D of D flip-flop 1542 is connected to power supply voltage Vcc, while output terminal Q thereof is connected to input terminal D of D flip-flop 1543 of the next stage. Then, an output terminal Q of the D flip-flop 1543 is output as a signal S3 which is a demodulation result.

Next, the waveform of each part in the receiving circuit 154 having the above configuration will be examined. When data is received from the electronic timepiece 200, the transistor 153 (see FIG. 5) does not switch, so that the other terminal D of the station-side coil 110 pulled up has an external magnetic field generated by the clock-side coil 210. If not, the level is a pull-up level. If an external magnetic field is generated, the level fluctuates at a level induced accordingly. Therefore, the signal S2 induced at the input terminal D is, for example, as shown in FIG.

In response to such a signal S2, a signal RST output from the inverter circuit 1541 is shown in FIG.
As shown in FIG. 7, when the voltage of the signal S2 falls below the threshold value Vth, the signal S2 goes high and the D flip-flop 1
542 and 1543 are reset. At this time, the D flip-flops 1542 and 1543 output the level of the input terminal D immediately before the rising of the clock signal CLK. Therefore, D flip-flop 1
542 and the D flip-flop 154
2 are as shown in FIGS. 10D and 10E, respectively. That is, the output signal S3 of the receiving circuit 154
Is a signal that becomes “L” level during the period when the external magnetic field is generated by the clock side coil 210. Here, the period during which the external magnetic field is generated by the clock side coil 210 is
As will be described later, the electronic clock 200 to the station 10
Since the data transferred to “0” is at the “L” level, it can be seen that the signal S3 is obtained by demodulating data and commands from the electronic timepiece 200.

[2.2.4] Configuration of Electronic Clock [2.2.4.1] Outline of Estimation Process of Secondary Battery Capacity in Electronic Clock First, prior to description of the configuration of the electronic clock, the configuration is employed. An outline of the process of estimating the secondary battery capacity in the electronic timepiece that has reached the point will be described. Electronic timepiece 2 of the first embodiment
00 is a charging current flowing to the secondary battery at the time of charging, a voltage at the time of interruption which is a voltage of the secondary battery at a point in time when a predetermined time has elapsed since the interruption of charging, and a secondary battery when charging is performed. Is detected, and the voltage difference between the interruption voltage and the charging voltage is calculated. Then, the internal resistance of the secondary battery is calculated based on the difference voltage and the charging current, and the capacity of the secondary battery is estimated based on the difference voltage and the internal resistance.

[2.2.4.2] Electrical Configuration Next, the electrical configuration of the electronic timepiece 200 will be described.
FIG. 11 shows a schematic configuration block diagram of an electronic timepiece. The electronic timepiece 200 is, as shown in FIG.
One terminal P of 0 is connected to the positive terminal of the secondary battery 220 via the diode 245, and the other terminal of the clock side coil 210 is connected to the negative terminal of the secondary battery 220. Therefore, when a pulse signal is applied to the station-side coil 110 (see FIG. 5) and an external magnetic field is generated, a signal is induced at one terminal P of the clock-side coil 210 by the external magnetic field. Then, this induced signal is rectified by the diode 245,
The secondary battery 220 is charged via the power supply 71. Then, the configuration is such that the voltage Vcc of the secondary battery 220 is used as a power source for each unit in the electronic timepiece 200.

The charging period detecting circuit 261 detects whether or not a signal is induced at the terminal P by an external magnetic field. Here, as shown in FIG. 12 (a), the timing T ₀
Thereafter, when a signal is induced at the terminal P at regular intervals, a signal CHR that becomes the “H” level is output as shown in FIG. Also, the battery voltage detection circuit 281
A voltage value Ev between both terminals of the secondary battery 220 is detected and output as digital data.

The register 282 temporarily stores the voltage value Ev detected by the battery voltage detection circuit 281 at the fall of the signal CHR. Therefore, the register 282 stores the voltage value Evc (=) of the secondary battery 220 during the period when the signal is induced at the terminal P, that is, during the charging period.
(Voltage at the time of charging). On the other hand, register 2
83 temporarily stores the voltage value Ev detected by the battery voltage detection circuit 281 at the rise of the signal CHR. Therefore, the register 283 stores the value of “1” immediately before the signal is induced at the terminal P, that is, 1 after the charging is interrupted.
Rechargeable battery 22 at the time when 0 seconds (= predetermined time) has elapsed
The voltage value Evd of 0 (= voltage at interruption) is stored.

On the other hand, the current detection circuit 291
20 is detected and output as digital data. The register 292 temporarily stores the current value Ei detected by the current detection circuit 291 at the fall of the signal CHR. Therefore, register 2
Reference numeral 92 denotes a period during which a signal is induced at the terminal P, that is, a current value Eic (=
(Charge current).

Next, the subtractor 284 subtracts the input value to the input terminal B from the input value to the input terminal A. Here, the voltage value Evc temporarily stored in the register 282 is input to the input terminal A of the subtractor 284, and the voltage of the register 283 is input to the input terminal B.
Are temporarily supplied. Therefore, the subtractor 284 outputs the voltage increase ΔEv due to the internal resistance of the secondary battery 220. On the other hand, the divider 293 divides the output value of the subtractor 284 by the output value of the register 292. Here, the subtractor 28
4 is the voltage rise ΔEv.
Is the current value E of the secondary battery 220 during the charging period.
Since it is ic, the divider 293 calculates the internal resistance Re of the secondary battery 220 by the following equation. Re = ΔEv / Eic

The conversion table group 285 is provided with a plurality of conversion tables 285-1 to 285-n for converting the voltage increase ΔEv into the battery capacity F and outputting the same. Each of the conversion tables 285-1 to 285-n corresponds to the secondary battery 2
The conversion tables 285-1 correspond to 20 different internal resistance values (or internal resistance value widths).
The corresponding relationship between the voltage increase ΔEv and the battery capacity F at 285-n is, for example, as shown in FIG. As described above and as shown in FIG. 13, as the charging of the secondary battery progresses, the voltage rise ΔEv (the transition from the time of charging to the time of discharging) accompanying the transition from the time of discharging to the time of charging. ΔEv
The smaller is, the larger the capacity of the secondary battery is. It should be noted that the correspondence shown in FIG.
These are properties to be determined according to the 20 characteristics.

The conversion table judging unit 294 includes a divider 29
Of the plurality of conversion tables 285-1 to 285-n constituting the conversion table group 285 based on the internal resistance Re of the secondary battery 220 calculated by the step S3.
Generating a selection signal SEL for specifying a conversion table to be used when converting Ev to battery capacity F and outputting it;
Output.

Next, the control circuit 230 is a kind of central processing control device provided with a temporary storage memory, an arithmetic unit, and the like, and usually corresponds to a mode set by the input unit 203 (not shown in FIG. 3). Control is performed to cause the display unit 204 to execute display (for example, current time display). However, in the state accommodated in the station 100, a signal is induced at the terminal P, and the signal CHR becomes “H”.
Upon transition to the level, the control circuit 230 first determines whether or not the capacity F converted and output by the conversion table 285 corresponds to the capacity in the fully charged state, and secondly, the command com1 corresponding to the determination result. Alternatively, a command com3 is created and transmitted during the period when the signal CHR is at the “L” level,
, After delivery of the command, if the transfer start button 103 ₂ is depressed, a process for outputting digital data to be transmitted to the station 100.

As digital data to be transmitted to the station 100, biological information such as a pulse rate and a heart rate measured by a sensor (not shown) is assumed. The meaning of the command com1 or the command com3 will be described later.

The transmission circuit 250 serializes data and commands to be transmitted to the station 100 and outputs a switching signal obtained by bursting a signal of a constant frequency during a period in which the serial data is at "L" level. is there. The switching signal from the transmission circuit 250 is supplied to the base of the transistor 252 via the resistor 251. The collector of the transistor is connected to the positive terminal of the secondary battery 220, while the emitter of the transistor is connected to one terminal P of the coil 210.
It is connected to the.

Therefore, in the electronic timepiece 200 having such a configuration, when a signal is induced at the terminal P as shown in FIG. 12A, as shown in FIG. While the signal is being induced, the signal CHR is at the “H” level, and the secondary battery 220 is charged during this period, as shown in FIG.
On the other hand, when no signal is induced at the terminal P and the signal CHR goes to "L" level, as shown in FIG. 12D, commands com1, command com3, digital data, and the like are transferred. I have.

[2.2.4.3. Next, operations of charging and data transfer of the station 100 and the electronic timepiece 200 will be described with reference to the block diagrams of FIGS. 5 and 11 and the flowcharts of FIGS. 15 and 16.

First, the user causes the electronic timepiece 200 to be housed in the recess 101 of the station 100. This allows
The station-side coil 110 and the watch-side coil 210 face each other as shown in FIG. 4 and are electromagnetically coupled. Thereafter, when the user presses the charge start button 103 ₁ or the transfer start button 103 ₂ , the timer A 141 is activated by the pulse signal STR.
And the timer B142 starts the count operation (step S101). Further, the charge / transfer switch 170 outputs the first charge signal as shown in FIG. 6A as the signal e by the pulse signal STR (step S10).
2).

Next, it is determined whether or not the timer A 141 has completed the counting operation, based on the inverted signal of the signal a (step S103). If it is determined in step S103 that the counting operation has been completed (step S10).
3; Yes), this means that the elapsed charge start button 103 ₁ or the transfer start button 103 ₂ is more than 10 hours after being pressed. Therefore, the processing circuit 13
A value of 0 causes the display unit 104 to perform a display as shown in FIG. 17B (step S104). Further, since the signal OFF becomes the “H” level due to the inverted signal of the signal a, the charge / transfer switch 170 holds the signal e at the “L” level. Thus, the charging of the electronic timepiece 200 ends. On the other hand, if it is determined in step S103 that the timer A141 has not completed the counting operation (step S103; No), the charge / transfer switch 170 outputs the first charge signal as the signal e. As a result, the station-side coil 110 generates an external magnetic field by switching by the transistor 153 during the period when the signal e is at the “H” level, and transmits a command from the electronic timepiece 200 during the period when the signal e is at the “L” level. It goes into a standby state to receive.

When the external magnetic field is generated, a signal is induced at the terminal P on the electronic timepiece 200 side. Here, if there is no remaining battery level of the secondary battery 220 at the present time (Step S201; No), since each part does not operate, the following Steps S201 to S207 cannot be executed, and no command is sent to the station 100 side. . On the other hand, if the remaining battery level is present (step S201; Yes), the voltage value Evc at the time of charging is temporarily stored in the register 282 (step S202).
The voltage value Evd at the time of charging interruption is temporarily stored in the register 283 (step S203). Then, the subtractor 284 reads the voltage value Evc stored in the register 282 and the voltage value Evd stored in the register 283, respectively, and subtracts the voltage value Evd from the voltage value Evc to obtain the internal resistance of the secondary battery 220. Voltage rise Δ
Ev is output (step S204).

In parallel with this, the current value Eic during charging is temporarily stored in the register 292 (step S205). Then, the divider 293 has the register 292
Read out the current value Eic stored in the
The internal resistance value Re is calculated by the following equation based on the voltage rise ΔEv output from the output terminal 84 (step S20).
6). Re = ΔEv / Eic The conversion table determiner 294 calculates a plurality of conversion tables 285 constituting the conversion table group 285 based on the internal resistance Re of the secondary battery 220 calculated by the divider 293.
-1 to 285-n, a selection signal SEL for specifying a conversion table to be used when actually converting the voltage rise ΔEv into the battery capacity F and outputting the same is output to the conversion table group 285. (Step S207).

Next, the conversion table group 285 includes a selection signal SEL among the plurality of conversion tables 285-1 to 285-n.
The voltage rise ΔE is calculated using one conversion table corresponding to
v is converted to capacity F and output. As a result, the voltage rise Δ
From Ev, the capacity of the secondary battery 220 taking into account the current internal resistance of the secondary battery 220 is estimated (step S208). The control circuit 230 determines whether or not the capacity F is a predetermined capacity that does not require further charging, for example, a capacity corresponding to a fully charged state (step S209). In the determination in step S209, when the capacity F is a capacity corresponding to a predetermined capacity that can be regarded as unnecessary for further charging (step S209;
Yes), since there is no need to charge thereafter, a command com3 is transmitted in order to notify the station 100 of that (step S210).

In the determination in step S209, the capacity F
However, when the charging does not correspond to the predetermined capacity that can be regarded as unnecessary (step S209; No),
Since the charging needs to be continued, a command com1 is sent to notify the station 100 of that fact (step S211). Command com1 or command co
m3 is transmitted during a period in which no signal is induced at the terminal P,
In other words, on the station 100 side, during the 10 second period when the signal e is at “L” level,
During the period when the signal CHR is at the “L” level,
Be executed.

As described above, when the signal is induced at the terminal P, the electronic timepiece 200 sets the charging current Eic flowing through the secondary battery 220 at the time of charging, and sets the charging current Eic at the time when a predetermined time has elapsed since the charging was interrupted. The interruption voltage Evd, which is the voltage of the secondary battery 220, and the charging voltage Evc, which is the voltage of the secondary battery 220 when charging is being performed, are detected, and the difference voltage between the interruption voltage Evd and the charging voltage Evc ( = Evd-E
vc) is calculated. Then, the electronic timepiece 200 calculates the internal resistance Re of the secondary battery 220 based on the voltage rise ΔEv and the charging current Eic, and further calculates the capacity of the secondary battery 220 based on the voltage rise ΔEv and the internal resistance Re. Estimated. Electronic clock 200
Is configured to determine whether or not the estimated battery capacity is a predetermined capacity, and to transmit a command corresponding to the determination result.

The station 100 executes the charging according to the first charging signal for at least a period of 30 minutes, which is the operation period of the timer B142. For this reason, the secondary battery 220 is not initially in a data transfer enabled state, and
Even if the command com1 or the command com3 is not transmitted from the electronic timepiece 200, the battery is charged for 30 minutes, so that the battery is charged at least up to the capacity for data transfer. That is, the electronic timepiece 200 is housed in the station 100 and the charge start button 103 ₁
Or after the transfer start button 103 ₂ has elapsed 30 minutes is pressed, the secondary battery 220 from become the data transfer state, has a structure in which either command com1 or command com3 is sent. Therefore, when no command is sent to the station 100,
Only when the electronic timepiece 200 is not housed in the station 100.

On the other hand, the station 10 in the standby state
At 0, it is determined whether or not either the command com1 or the command com3 has been received from the electronic timepiece 200 (step S111). In the determination of step S111, when neither the command com1 nor the command com3 is received (step S111; No), the timer B142
It is determined whether or not has completed the counting operation (step S112). Specifically, the command detector 160 checks whether or not the signal c has become the “H” level during the 30 minute period when the signal b has the “H” level.

In this case, even if the timer B142 ends the counting operation (step S112; Yes),
The case where no command com1 or command com3 is received means that the electronic watch 200
0 is not accommodated in the command detector 16
This is the case where the signal d due to 0 becomes “H” level. Accordingly, the processing circuit 130 causes the display unit 104 to perform a warning display as shown in FIG. 17A, for example, as a result of the signal d transitioning to the “H” level (step S113). To that effect. Further, since the signal OFF changes to “H” level by the signal d, the charge / transfer switch 170 holds the signal e at “L” level. For this reason, the unnecessary charging operation when the electronic timepiece 200 is not accommodated ends. On the other hand, if the timer B142 has not completed the count operation (Step S112; No), the process proceeds to Step S102 again to continue charging, and the transmission of the first charging signal is continued.

Now, the station 10 in the standby state
At 0, if any command is received from the electronic timepiece 200, the received command is decoded by the decoder 155 (step S114). Here, if the received command is com1, it is determined whether or not the _first pressed button is the charge start button 1031 (step S115). More specifically, the charge / transfer switch 170 receiving the signal com1 determines whether or not the signal CS has been supplied before. In the determination of step S115, the button pressed first is the charging start button 1
03 ₁ (Step S115; Ye
s), the charge / transfer switch 170 outputs the signal e to be transmitted,
The first charge signal shown in FIG. 6A is switched to the second charge signal shown in FIG. 6B. Then, the process proceeds to step S103 to continue charging.

As described above, charging is performed during the "H" level period of the signal e, while data transfer is performed during the "L" level period of the signal e. Further, the period during which the signal e as the second charging signal is at the “H” level is longer than that of the first charging signal. Therefore, the transmission of the second charging signal reduces the frequency of receiving a command as a result of checking whether or not the charging time t has elapsed, while prolonging the charging period. Will be improved. On the other hand, the received command is a com1, in the judgment of step S115, when button pressed at the beginning of the transfer start button 103 ₂ (step S115; No), step S12 to be described later
The data transfer of 1 to S123 is executed.

If the received command is the command com3, the first pressed button is the charge start button 103
It is determined whether it was ₁ (step S11).
7). Specifically, the charge / transfer switch 170, which has been supplied with the signal OFF by the signal com3, determines whether or not the signal CS has been supplied before. In the determination of step S117, the button pressed first is the charging start button 1
03 ₁ (Step S117; Ye
s) Since there is no need to charge the secondary battery 220 any more, the charge / transfer switch 170 holds the signal e at the “L” level. As a result, the unnecessary charging operation for charging the battery with the desired capacity or more ends. On the other hand, the received command is com3, and in the determination of step S117, the first pressed button is the transfer start button 103
If it is ₂ (step S117; No), the data transfer of the next steps S121 to S123 is executed.

That is, the digital data transmitted following the commands com1 and com3 is transmitted to the receiving circuit 154.
, Decoded by the decoder 155, and transferred to the processing circuit 130 (step S12).
1), repeated until the process is completed (step S12)
2). When this transfer is completed, the processing circuit 130
Is displayed on the display unit 104, for example, as shown in FIG. 17C (step S12).
2) Display on the display unit 104 based on the received digital data. Thereafter, the processing circuit 130 uses the line not shown in FIG.
, The supply of the signal e is stopped to end the charging / data transfer.

[2.3] Effect of First Embodiment As described above, in the first embodiment, the charge start button 1
03 ₁ or the transfer start button 103 ₂ is pressed,
Since the first charging signal is transmitted from the station 100 as the signal e, the secondary battery 220 of the electronic timepiece 200 is intermittently charged. Here, the electronic timepiece 200 is configured such that the charging current Eic flowing through the secondary battery 220 during charging, the interruption voltage Evd which is the voltage of the secondary battery 220 at a point in time when a predetermined time has elapsed since the charging was interrupted, and the charging are performed. The charging voltage Evc, which is the voltage of the secondary battery 220 when the operation is performed, is detected, and the interruption voltage Evd and the charging voltage Evc are detected.
And the internal resistance Re of the secondary battery 220 is calculated based on the voltage rise ΔEv and the charging current Eic, and further calculates the voltage rise ΔEv and the voltage rise ΔEv. Secondary battery 2 based on internal resistance Re
The capacity of the battery 20 is estimated, and it is determined whether or not the estimated battery capacity is a predetermined capacity.

If the estimated battery capacity has not reached the predetermined capacity, the command com1 is sent to the station 100.
As a result, the second charging signal (see FIG. 6B) is used as the signal e for switching between charging and data transfer, so that the charging efficiency of the electronic timepiece 200 is improved. If the estimated battery capacity has reached the predetermined capacity, the command com3 is sent to the station 100, and as a result, the signal e is held at the “L” level, and thus the charging ends. Therefore, according to the present embodiment,
The battery capacity is estimated from the voltage rise ΔEv obtained by intermittently performing charging and the internal resistance Re of the secondary battery, and when the estimated capacity reaches a desired capacity, for example, a capacity corresponding to a fully charged state, charging is stopped. Since the process is completed, the inconvenience of unnecessary charging is eliminated.

[3] Second Embodiment Next, a second embodiment of the present invention will be described. In the first embodiment, the charging is performed intermittently, the voltage rise ΔEv of the secondary battery 220 when the transition from the discharging to the charging is obtained, and the current and the voltage rising ΔEv during the charging are obtained. , The internal resistance of the secondary battery 220 is obtained, and the voltage rise ΔEv
And the battery capacity is estimated based on the internal resistance. On the other hand, in the second embodiment, the charging is executed intermittently, and the transition from the charging to the discharging is performed at the time of the charging (the voltage immediately before the charging is interrupted or the voltage immediately after the charging is interrupted and the discharging resistor to be described later). The voltage before connection), the voltage at the time of interruption of charging, and the discharge resistor connected to the secondary battery to detect the voltage (= discharge voltage) after connecting the resistor, the voltage at interruption, the voltage after connection of the resistor, and the The internal resistance of the secondary battery is calculated from the resistance value, and the capacity of the secondary battery is estimated based on the difference voltage between the charging voltage and the interruption voltage and the internal resistance.

[3.1] Electrical Configuration First, the electrical configuration of the electronic timepiece 200A will be described. FIG. 18 shows a schematic block diagram of an electronic timepiece.
In FIG. 18, the same parts as those in the first embodiment of FIG. 11 are denoted by the same reference numerals, and detailed description thereof will be omitted. The electronic timepiece 200A includes a diode 24 as shown in FIG.
5, a discharge resistor 301 having a resistance value R with one terminal connected to a connection point between the cathode terminal of the secondary battery 220 and a collector terminal connected to the other terminal of the discharge resistor 301, and an emitter terminal connected to ground. And a switching transistor 302 which is provided. Under the control of the control circuit 230, the discharge resistance switching circuit 303
As shown in FIG. 9, after detecting the voltage value Evd of the secondary battery 220 at the time of interruption of charging, the switching transistor 302 is turned on (closed), the discharging resistor 301 is connected in parallel to the secondary battery 220, and the discharge path is connected. Let it form. Further, the battery voltage detection circuit 281 detects a voltage value Ev between both terminals of the secondary battery 220 and outputs it as digital data.

Register 282 temporarily stores voltage value Ev detected by battery voltage detection circuit 281 at the fall of signal CHR. Therefore, the register 282 stores the voltage value Evc (=) of the secondary battery 220 during the period when the signal is induced at the terminal P, that is, during the charging period.
(Voltage at the time of charging). The timing for detecting the voltage value Evc is preferably immediately before the interruption of charging or immediately after resuming the charging. However, the timing for detecting the voltage value Evc can be similarly used immediately after the interruption of charging. Register 283
Temporarily stores the voltage value Ev detected by the battery voltage detection circuit 281 at the rise of the signal CHR. Therefore, the register 283 stores the value of 10 just before the signal is induced at the terminal P, that is, 10 minutes after the charging is interrupted.
Rechargeable battery 220 at the point in time when second (= predetermined time) has elapsed
(= Interruption voltage; see FIG. 19).

The register 304 stores the voltage value Evr of the secondary battery 220 (= voltage after resistance connection; see FIG. 19) at a point in time when a predetermined time has elapsed since the discharge resistance switching circuit 303 connected the discharge resistance 301. Will be done.

Next, the subtractor 284 subtracts the input value to the input terminal B from the input value to the input terminal A. Here, the voltage value Evc temporarily stored in the register 282 is input to the input terminal A of the subtractor 284, and the voltage of the register 283 is input to the input terminal B.
Are temporarily supplied. Therefore, the subtractor 284 outputs the voltage increase ΔEv due to the internal resistance of the secondary battery 220. On the other hand, the internal resistance calculation circuit 305
The internal resistance Re of the secondary battery 220 is calculated by the following equation based on the voltage value Evd, which is the output value of the secondary battery, the voltage value Evr, which is the output value of the register 304, and the resistance value R of the discharge resistor 301. Re = R · (Evd−Evr) / Evr

The conversion table group 285 includes a plurality of conversion tables 285-1 to 285-n for converting the voltage increase ΔEv (= Evd−Evc) into a battery capacity F and outputting the same. I have. Each conversion table 285-1 to 285
-n corresponds to different internal resistance values (or internal resistance value widths) of the secondary battery 220, respectively.

The conversion table judging unit 294 includes the dividing unit 29
Of the plurality of conversion tables 285-1 to 285-n constituting the conversion table group 285 based on the internal resistance Re of the secondary battery 220 calculated by the step S3.
A selection signal SEL for specifying a conversion table to be used when converting Ev (= Evd-Evc) into a battery capacity F and outputting the same is generated and output. Hereinafter, similarly to the first embodiment, when the battery capacity estimated from the voltage value Evd, the voltage value Evc, and the resistance value R reaches a predetermined capacity, for example, a capacity corresponding to a fully charged state, Since the charging is completed at the point in time, the inconvenience of performing unnecessary charging is eliminated as in the first embodiment. If the estimated battery capacity has not reached the predetermined capacity, the second charging signal (see FIG. 4B) is used as the signal e, so that the electronic timepiece 200A
The same applies to the point that charging efficiency to the battery is improved.

[4] Third Embodiment Next, a third embodiment of the present invention will be described. The second
In the embodiment, the voltage measurement at the time of interruption of charging is performed before connecting the discharge resistor, and the internal resistance of the secondary battery is calculated from the voltage at interruption, the voltage after connection of the resistor, and the resistance value of the discharge resistor. Although the capacity of the secondary battery is estimated on the basis of the difference between the voltage and the voltage after connection of the resistor and the internal resistance, the third embodiment uses a discharge resistor to measure the voltage when charging is interrupted. After the discharge, the voltage after the connection of the resistor (= discharge voltage) is detected after the discharge, and the internal resistance of the secondary battery is calculated from the voltage at the time of interruption, the voltage after the connection of the resistor, and the resistance value of the discharge resistor. A configuration is adopted in which the capacity of the secondary battery is estimated based on the difference voltage from the voltage after connection and the internal resistance.

The structure of the electronic timepiece according to the third embodiment is similar to that of the second embodiment.
Since it is the same as the embodiment, the detailed description is referred to,
Hereinafter, only different portions will be described. Under the control of the control circuit 230, the discharge resistance switching circuit 303 turns on (closes) the switching transistor 302 when charging is interrupted, connects the discharge resistor 301 in parallel with the secondary battery 220, and forms a discharge path. Also, the battery voltage detection circuit 28
1 detects a voltage value Ev between both terminals of the secondary battery 220 and outputs it as digital data.

Then, register 283 temporarily stores voltage value Ev detected by battery voltage detection circuit 281 at the rise of signal CHR. Therefore,
The register 283 stores the rechargeable battery 220 immediately before the signal is induced at the terminal P, that is, at the time when the first predetermined time has elapsed since the charging was interrupted and the discharging resistor was connected.
(= Interruption voltage; see FIG. 20).

The register 304 has a voltage value Evr of the secondary battery 220 at the time when the second predetermined time has elapsed from the connection of the discharge resistor 301 by the discharge resistor switching circuit 303 (= voltage after resistor connection; see FIG. 20). ) Will be stored.

Next, the subtractor 284 subtracts the input value to the input terminal B from the input value to the input terminal A. Here, the voltage value Evc temporarily stored in the register 282 is input to the input terminal A of the subtractor 284, and the voltage of the register 283 is input to the input terminal B.
Are temporarily supplied. Therefore, the subtractor 284 outputs the voltage increase ΔEv due to the internal resistance of the secondary battery 220. On the other hand, the internal resistance calculation circuit 305
The internal resistance Re of the secondary battery 220 is calculated by the following equation based on the voltage value Evd, which is the output value of the secondary battery, the voltage value Evr, which is the output value of the register 304, and the resistance value R of the discharge resistor 301. Re = R · (Evd−Evr) / Evr

The conversion table group 285 includes a plurality of conversion tables 285-1 to 285-n for converting the voltage rise ΔEv into the battery capacity F and outputting the same. Each of the conversion tables 285-1 to 285-n corresponds to the secondary battery 2
These correspond to 20 different internal resistance values (or internal resistance value widths).

The conversion table decision unit 294 is
Of the plurality of conversion tables 285-1 to 285-n constituting the conversion table group 285 based on the internal resistance Re of the secondary battery 220 calculated by the step S3.
Generating a selection signal SEL for specifying a conversion table to be used when converting Ev to battery capacity F and outputting it;
Output. Hereinafter, similarly to the first embodiment, the voltage value E
If the battery capacity estimated from vd, the voltage value Evr, and the resistance value R reaches a predetermined capacity, for example, a capacity corresponding to a fully charged state, the charging is terminated at that point, and the first
As in the embodiment, the inconvenience of performing unnecessary charging is eliminated. If the estimated battery capacity does not reach the predetermined capacity, the second charging signal (see FIG. 4B) is used as the signal e, which also improves the charging efficiency of the electronic timepiece 200A. It is.

[5] Fourth Embodiment [5.1] Explanation of Principle of Fourth Embodiment In each of the above embodiments, the internal resistance of the secondary battery 220 is calculated, and based on the internal resistance and the voltage increase ΔEv. Although the battery capacity has been calculated, the internal resistance of the secondary battery 220 has a temperature characteristic that changes according to the temperature of the secondary battery 220. More specifically, as shown in FIG. 21, as the temperature of the secondary battery 220 increases, it tends to decrease. Therefore, in the fourth embodiment, in addition to the configuration of each of the above embodiments, a temperature detecting unit such as a temperature sensor for detecting the temperature of the secondary battery 220 or the temperature around the secondary battery 220 is provided. Further, a temperature correction means such as a correction arithmetic circuit for correcting the internal resistance calculated in each of the above embodiments based on the detected temperature is provided. As a result, a more accurate internal resistance of the secondary battery 220 can be calculated, and a more accurate battery capacity can be calculated.

[6] Fifth Embodiment In each of the above embodiments, when charging the secondary battery 220 at a constant voltage, the charging voltage is a predetermined constant voltage. By the way, the charging voltage is actually the secondary battery 2
20 does not represent the true charging voltage of the secondary battery 220. on the other hand,
If the true charging voltage of the secondary battery 220 exceeds a predetermined reference voltage, the deterioration of the secondary battery 220 is caused. Therefore, in the fifth embodiment, in addition to the configuration of the first embodiment, the interruption voltage Evd and the charging current Eic
A true voltage calculation unit such as an arithmetic circuit that calculates a true voltage of the secondary battery 220 based on the internal resistance Re, and a charge voltage control unit such as a charge voltage controller that controls a voltage during constant voltage charging; As a configuration including the secondary battery 2
The configuration is such that the voltage during constant voltage charging is controlled so that the true battery voltage of the battery does not exceed a predetermined reference value. As a result, charging can be performed without the charging voltage of the true secondary battery 220 exceeding a predetermined reference voltage, and deterioration of the secondary battery 220 can be reduced.

[7] Sixth Embodiment In the above-described first embodiment, the time set by the timer A 141 for performing the full charge of the secondary battery 220 is a predetermined time (for example, 10 hours in the above example). ) However, as shown in FIG.
As the deterioration of 20 progresses, in order to obtain the same battery capacity,
A larger value is required for the voltage rise ΔEv. Therefore, conversely, when the same voltage rise ΔEv is observed,
When charging is performed for the same charging time, if the secondary battery 220 is deteriorated, an overcharged state occurs, and the secondary battery 220 is further deteriorated. Also, the secondary battery 2
The more the deterioration of 20 proceeds, the higher the internal resistance increases (see FIG. 23).

Therefore, in the sixth embodiment, a full charge timer means such as a full charge timer for managing a charge time for performing a full charge of the secondary battery 220 is provided.
It is configured such that the degree of deterioration of the secondary battery 220 is estimated based on the calculation result of the internal resistance, and timer control means such as a timer controller for controlling the full charge timer means is provided. In this case, the relationship between the number of storage days and the change state of the internal resistance as shown in FIG. 23 is stored in advance as a table or a mathematical expression, and the actual number of storage days is measured.
Further, it is preferable to provide a deterioration degree calculating means such as a deterioration degree calculating circuit for measuring the storage temperature by a temperature sensor or the like and calculating the deterioration degree of the secondary battery. Further, it is also possible to cause the display unit 204 as the deterioration degree display means to display the deterioration degree indicating the calculated deterioration degree.

[7.1] Modification of Sixth Embodiment In the above description, the configuration in which the degree of deterioration of the secondary battery 220 is always detected based on the calculation result of the internal resistance is replaced with the configuration, or together with the configuration. By determining whether the calculated internal resistance exceeds a predetermined reference internal resistance value, it is also possible to determine the degree of deterioration at which battery replacement should be performed. In this case, it is desirable that the obtained deterioration degree determination result (battery replacement should be performed) is displayed on the display unit 204 as deterioration determination result display means. [7.2] Effects of Sixth Embodiment According to the sixth embodiment, even when the secondary battery 220 is deteriorated, it is possible to avoid an overcharged state, and further a secondary battery is provided. There is no possibility of deterioration of 220. In addition, when the calculated internal resistance exceeds a predetermined reference internal resistance value, it is possible to easily notify that it is time to replace the battery.

[8] Seventh Embodiment In each of the above embodiments, the charge interruption time is fixed. However, in the seventh embodiment, the charge interruption time is set longer as the internal resistance increases. This is an embodiment to be performed. Battery voltage rise ΔE during charging
v tends to increase with charging time due to the polarization of ions and charges inside the battery. Therefore, in a battery that has deteriorated and the internal resistance has increased, the battery voltage can be reduced to a charging limit voltage (for example, about 4.
2 [V]), which causes a problem that sufficient charging cannot be performed. Therefore, in the seventh embodiment, as the secondary battery deteriorates and the internal resistance of the secondary battery increases, the charge interruption time in intermittent charging is set to be longer. As a result, the effective charging time until reaching the charging limit voltage can be extended, and sufficient charging can be performed even for a deteriorated secondary battery.

[9] Modified Example of Embodiment [9.1] First Modified Example In the above-described embodiment, the data transfer was only in one direction from the electronic timepiece 200 to the station 100. Of course, it may be the direction to. When data is transferred to the electronic timepiece 200, the station 100 modulates the data according to the data to be transferred, while the electronic timepiece 200 performs demodulation in accordance with the modulation method. At this time, a known technique may be applied to modulation and demodulation.

[9.2] Second Modification In the above embodiment, one battery voltage detection circuit 28
1, the voltage value Evc during charging, the voltage value Evd during interruption of charging, or the voltage value Evr during discharging,
However, the configuration may be such that separate battery voltage detection circuits detect the voltage value Evc during charging, the voltage value Evd during charging interruption, and the voltage value Evr during discharging, respectively. Note that the configuration in which detection is performed by one battery voltage detection circuit 281 as in the above-described embodiment is more advantageous in that detection errors due to different detection circuits do not occur and in terms of device cost.

[0099]

As described above, according to the present invention, the capacity of a charged secondary battery can be estimated with a simple configuration in consideration of the internal resistance or the deterioration of the secondary battery. Becomes

[Brief description of the drawings]

FIG. 1 is a diagram showing charge / discharge characteristics of a general secondary battery.

FIG. 2 is a circuit diagram for explaining a voltage rise accompanying a transition from discharging to charging.

FIG. 3 is a plan view showing a configuration of a station and an electronic timepiece according to the first embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of the station and the electronic watch of the first embodiment.

FIG. 5 is a block diagram illustrating an electrical configuration of a station according to the first embodiment.

FIGS. 6A and 6B are diagrams showing waveforms of first and second charging signals, respectively, which are signals e in the station according to the first embodiment.

FIG. 7 is a block diagram illustrating a configuration of a command detector in the station according to the first embodiment.

FIGS. 8A and 8B are timing charts for explaining the operation of the command detector according to the first embodiment.

FIG. 9 is a circuit diagram illustrating an example of a receiving circuit of the station according to the first embodiment.

FIGS. 10A to 10E are timing charts for explaining the operation of the receiving circuit of the first embodiment;

FIG. 11 is a block diagram illustrating an electrical configuration of the electronic timepiece according to the first embodiment.

FIGS. 12A to 12D are timing charts for explaining the operation of the electronic timepiece according to the first embodiment.

FIG. 13 is a diagram showing a relationship between a battery rise and a voltage rise ΔEv associated with a transition from discharging to charging in intermittent charging.

FIG. 14 is a diagram showing conversion contents in a conversion table.

FIG. 15 is a flowchart illustrating an operation of charging and data transfer between the station and the electronic timepiece according to the first embodiment.

FIG. 16 is a flowchart illustrating an operation of charging and data transfer between the station and the electronic watch of the first embodiment.

FIGS. 17A to 17C are diagrams each showing an example of display on the display unit in the station according to the first embodiment.

FIG. 18 is a block diagram illustrating a configuration of an electronic timepiece according to a second embodiment of the invention.

FIG. 19 is a diagram for explaining the operation of the second embodiment.

FIG. 20 is a diagram for explaining the operation of the third embodiment.

FIG. 21 is a diagram illustrating temperature characteristics of internal resistance.

FIG. 22 is a diagram illustrating the relationship between battery deterioration and voltage rise ΔEv.

FIG. 23 is a diagram illustrating a change in internal resistance due to battery deterioration.

[Explanation of symbols]

 100 station, 110 station coil, 130 processing circuit, 170 charge / transfer switching device, 200 electronic clock, 210 clock coil, 220 secondary battery, 230 Control circuit 245 Diode 250 Transmission circuit 154 Receiving circuit 281 Battery voltage detection circuit 285 Conversion table group 285-1 to 285-n Conversion table 291 Current detection Circuit, 294 conversion table determiner 301, discharge resistor 302, switching transistor 303, discharge resistance switching circuit 305, internal resistance calculation circuit

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[Procedure amendment]

[Submission date] December 15, 1998 (1998.12.
15)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] FIG.

[Correction method] Added

[Correction contents]

FIG. 24 is a diagram illustrating a relationship between a terminal voltage of a secondary battery and an internal resistance during charging.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ichiro Aoshima 3-5-5 Yamato, Suwa-shi, Nagano F-term in Seiko Epson Corporation (reference) 2G016 CB05 CB06 CB11 CB12 CB31 CC04 CC06 CC10 CC12 CC13 CC23 CC27 CC28 CD02 CD03 CD04 CD07 CD09 CD14 CE00 5G003 AA01 BA01 CA01 CA18 CA20 CB06 CC04 EA05 EA09 GB08 GC05 5H030 AA03 AA06 AS11 BB02 BB04 DD18 FF42 FF43 FF44 FF52

Claims (15)

[Claims] A charging means for intermittently charging the secondary battery; a current detecting means for detecting a charging current that is a current flowing through the secondary battery during the charging; and a charging means for interrupting charging by the charging means. An interruption voltage detecting means for detecting an interruption voltage, which is a voltage of the secondary battery at a point in time when a predetermined time elapses from, and a voltage of the secondary battery when charging by the charging means is performed. A charging voltage detecting means for detecting a certain charging voltage; a subtracting means for subtracting the charging voltage from the interruption voltage to calculate a difference voltage; and the secondary based on the difference voltage and the charging current. An electronic apparatus comprising: an internal resistance calculating unit that calculates an internal resistance of a battery; and an estimating unit that estimates a capacity of the secondary battery based on the difference voltage and the internal resistance. 2. A charging unit for intermittently charging a secondary battery, and an interruption being a voltage of the secondary battery at a point in time when a predetermined first predetermined time has elapsed since the charging by the charging unit was interrupted. An interruption voltage detecting means for detecting an hour voltage, and a charging voltage detecting means for detecting a charging voltage that is a voltage of the secondary battery when charging is being performed by the charging means; and Subtraction means for subtracting the voltage at the time of charge to calculate a difference voltage, and resistance connection means for connecting a discharge resistor having a predetermined resistance value determined in advance after the detection of the interruption voltage, in parallel with the secondary battery, A post-resistance connection voltage detecting means for detecting a post-resistance connection voltage that is a voltage of the secondary battery at a point in time when a predetermined second predetermined time has elapsed since the discharge resistor was connected; Said An internal resistance calculating means for calculating the internal resistance of the secondary battery from the voltage after resistance connection and the resistance value; and an estimating means for estimating the capacity of the secondary battery based on the difference voltage and the internal resistance. Electronic equipment characterized by the above. 3. A charging means for intermittently charging a secondary battery, and a resistance connection for connecting a discharging resistor having a predetermined resistance value in parallel with the secondary battery when charging by the charging means is interrupted. Means, a predetermined first predetermined time before the interruption of the charging by the charging means, after the lapse of the first predetermined time from the restart of the charging by the charging means, or from the interruption of the charging by the charging means. Charging voltage detecting means for detecting a charging voltage which is a voltage of the secondary battery at any one time after the first predetermined time has elapsed; a second predetermined voltage which has been predetermined from the time of interruption of the charging; A post-resistor connection voltage detection means for detecting a post-resistor connection voltage that is a voltage of the secondary battery at a time point when time has elapsed; and a subtraction means for subtracting the resistance connection voltage from the charging voltage voltage to calculate a difference voltage. An internal resistance calculation unit that calculates an internal resistance of the secondary battery from the difference voltage and the resistance value; and an estimation unit that estimates a capacity of the secondary battery based on the difference voltage and the internal resistance. Electronic equipment characterized by the above. 4. The electronic device according to claim 1, wherein a temperature of the secondary battery or a temperature of a surrounding area of the secondary battery is detected. An electronic device comprising: a temperature correction unit that corrects the internal resistance calculated by the internal resistance calculation unit based on the calculated temperature. 5. The electronic device according to claim 1, wherein a true voltage calculating unit that calculates a true voltage of the secondary battery based on the interruption voltage, the charging current, and the internal resistance, and Charging voltage control means for controlling the voltage at the time of constant voltage charging in the means, wherein the voltage at the time of constant voltage charging is controlled so that the true battery voltage does not exceed a predetermined reference value. And electronic equipment. 6. The charge interruption period for controlling the charge interruption period in the charging means based on the calculated internal resistance of the secondary battery in the electronic device according to claim 1. An electronic device comprising a control unit. 7. The electronic device according to claim 6, wherein the charging interruption period control means sets the interruption period longer as the internal resistance of the secondary battery increases. 8. The electronic device according to claim 1, wherein a full charge timer means for managing a charge time for performing a full charge of the secondary battery; An electronic device, comprising: timer control means for controlling the full charge timer means based on a calculation result. 9. The electronic device according to claim 1, further comprising: a deterioration degree calculating unit that calculates a deterioration degree of the secondary battery based on a calculation result of the internal resistance. Electronic equipment characterized by the following. 10. The electronic device according to claim 9, further comprising a deterioration degree display unit for displaying the calculated degree of deterioration. 11. The electronic device according to claim 1, further comprising: a deterioration degree determination unit configured to determine whether the calculated internal resistance exceeds a predetermined reference internal resistance value. Electronic equipment characterized by the above. 12. The electronic device according to claim 11, further comprising: a deterioration determination result display unit that displays a determination result of the deterioration degree determination unit. 13. A charging step of intermittently charging a secondary battery, a current detecting step of detecting a charging current that is a current flowing through the secondary battery during the charging, and a step of interrupting charging in the charging step. An interruption voltage detection step of detecting an interruption voltage that is a voltage of the secondary battery at a point in time when a predetermined time has elapsed from a predetermined time, and a voltage of the secondary battery when charging is performed in the charging step. A charging voltage detection step of detecting a certain charging voltage; a subtraction step of subtracting the charging voltage voltage from the interruption voltage to calculate a difference voltage; and calculating the difference based on the difference voltage and the charging current. An internal resistance calculating step of calculating an internal resistance of the secondary battery; and an estimating step of estimating a capacity of the secondary battery based on the difference voltage and the internal resistance. Capacity estimation method of the pond. 14. A charging step of intermittently charging the secondary battery, and an interruption being a voltage of the secondary battery at a point in time when a predetermined first predetermined time has elapsed since the interruption of the charging in the charging step. An interruption voltage detection step of detecting an hour voltage; and a charging voltage detection step of detecting a charging voltage that is a voltage of the secondary battery when charging is being performed in the charging step. A subtraction step of subtracting the charging voltage voltage to calculate a difference voltage, and a resistance connection step of connecting a discharging resistor having a predetermined resistance value after detection of the interruption voltage in parallel with the secondary battery. A post-resistance connection voltage detection step of detecting a post-resistance connection voltage that is a voltage of the secondary battery at a point in time when a predetermined second predetermined time has elapsed after the connection of the discharge resistor; Voltage, an internal resistance calculation step of calculating the internal resistance of the secondary battery from the voltage after the resistance connection and the resistance value, and an estimation step of estimating the capacity of the secondary battery based on the difference voltage and the internal resistance. A method for estimating the capacity of a secondary battery, comprising: 15. A charging step of intermittently charging a secondary battery, and a resistance connection for connecting a discharging resistor having a predetermined resistance value in parallel with the secondary battery when charging is interrupted in the charging step. And a first predetermined step from the time of interruption of charging in the charging step.
A predetermined time before, after the elapse of the first predetermined time from the restart of charging in the charging step, or at any one time after the elapse of the first predetermined time from the interruption of charging in the charging step. A charging-time voltage detecting step of detecting a charging-time voltage that is a voltage of the secondary battery; and after connecting a resistor that is a voltage of the secondary battery at a point in time when a predetermined second predetermined time has elapsed since the interruption of the charging. A voltage detecting step after connecting a resistor for detecting a voltage, a subtracting step of calculating the difference voltage by subtracting the voltage at the time of the resistor connection from the voltage at the time of charging, and an internal resistance of the secondary battery from the difference voltage and the resistance value. A method for estimating the capacity of a secondary battery, comprising: calculating an internal resistance to calculate; and estimating a capacity of the secondary battery based on the difference voltage and the internal resistance.