JP3342947B2 - Battery remaining capacity notification device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery-applied device using a primary battery or a secondary battery, and detects and displays a decrease in battery voltage due to a decrease in the remaining capacity of the battery to replace or replace the battery. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery remaining capacity informing device for prompting charging.

[0002]

2. Description of the Related Art As shown in FIG. 26 and FIG. 27, a battery application device to which a conventional battery remaining capacity notification device is applied detects a voltage of a battery 101 by a voltage detection circuit 104, and detects the battery voltage. The battery voltage is compared with a preset reference voltage Vth, and when the battery voltage becomes equal to or lower than the reference voltage Vth, a low-level signal is output to turn on the LED 105 to indicate that the battery voltage has dropped. The display circuit 106 including the voltage detection circuit 104 and the LED 105 is
When directly connected to the battery 101 without passing through the power switch 102, the battery 101 is further consumed by power consumption of the LED 105 which is turned on as the battery voltage decreases. For this reason, as shown in FIG.
Are connected in parallel with the load 103 so that the power supply switch 102 is turned on and operates only when the device is used. Thus, when the power switch 102 is turned off, the LED 105 is also turned off at the same time.

[0003]

However, when the above-mentioned conventional battery remaining capacity informing device is applied to a battery application device such as an electric shaver, an electric toothbrush or a cordless telephone handset, it is assumed that the LED 105 is lit during use. Also,
Considering the usage of these applied devices, it is difficult to directly observe the lighting, and there is a problem that the battery voltage drops, that is, the remaining capacity is not noticed, and the notification function is fully utilized. Did not.

An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a battery remaining capacity notifying device for surely notifying a user that the remaining battery capacity has decreased.

[0005]

In order to achieve the above object, the present invention relates to a battery application device having a power switch interposed between a battery and a load and for turning on and off the operation of the device. And a voltage detection means for outputting a detection signal when the detected battery voltage is equal to or lower than a preset reference voltage, and outputting a notification signal when the detection signal is output when the power switch is turned on. And control means for holding the output of the notification signal until a predetermined time elapses after the power switch is switched from on to off, and notification means operable in response to the notification signal, wherein the control means Has reference voltage level switching means for changing the reference voltage to a higher level when the power switch is off, and outputs a control signal when the power switch is on. Then, after the power switch is switched from on to off, the output of the control signal is continued until a predetermined time elapses, and both the notification signal and the detection signal and the control signal are output. During this period, the output is made (claim 1).

Further, in the battery remaining capacity notification device according to the first aspect, the detection signal is output only for a time corresponding to a period during which the battery voltage falls below the reference voltage, and the notification is performed. (Claim 2).

The present invention also relates to a battery application device having a power switch interposed between a battery and a load and for turning on and off the operation of the device, detecting the battery voltage and setting the detected battery voltage in advance. Voltage detection means for outputting a detection signal when the voltage is equal to or lower than the reference voltage, and outputting a notification signal when the detection signal is output when the power switch is on, and switching the power switch from on to off. After that, a control unit that holds the output of the notification signal until a predetermined time elapses, and a notification unit that operates in response to the notification signal, wherein the voltage detection unit turns on the power switch as the reference voltage. After that, it is set to a first reference voltage for detecting a drop in battery voltage for outputting the detection signal, and after detecting the drop in battery voltage, a second reference voltage (> first reference voltage) is set. And the second reference voltage is self-recovered from the first reference voltage during a period from the turning-off of the power switch until the predetermined time elapses. It is set at a level or higher (claim 3).

The control means does not accept a detection signal from the voltage detection means for a predetermined start-up time after the power switch is turned on.

The control means includes a capacitor which starts charging when the power switch is turned on and starts discharging when the power switch is turned off, and outputs a signal when the output voltage of the capacitor is equal to or higher than a predetermined level.
The detection signal is received during the output period of this signal (claim 5).

Further, the reference voltage switching means cancels the setting of the second reference voltage when the predetermined time has elapsed (claim 6).

Further, the reference voltage switching means is adapted to hold the setting of the second reference voltage until the battery voltage exceeds the second reference voltage (claim 7).

[0012]

According to the first aspect of the present invention, when the battery voltage detected during the operation of the device falls below a preset reference voltage, a notification signal is output, and the output of the notification signal is based on the operation of the device. The operation is continued until a predetermined time elapses from the stop.
Then, the notification means operates in response to the notification signal. Also, a control signal is output during the operation of the device and until a predetermined time elapses after the operation is stopped. On the other hand, when the battery voltage detected during operation of the device becomes equal to or lower than a preset reference voltage, a detection signal is output, and when the operation of the device stops, the reference voltage level increases. The notification signal is output while both the detection signal and the control signal are output,
The notification means operates in response to the notification signal.

According to the second aspect of the present invention, the detection signal is output only for a period corresponding to the period during which the battery voltage has dropped below the reference voltage. As for the detection, the notification is not performed after the lapse of the period of the erroneous detection state, so that there is no erroneous determination.

According to the third aspect of the present invention, when the battery voltage detected during operation of the device falls below a preset reference voltage, a notification signal is output, and the notification signal is output from the device. The operation is continued until a predetermined time elapses after the operation is stopped. Then, the notification means operates in response to the notification signal. The reference voltage switching means switches to the first reference voltage as a reference voltage for detecting a decrease in battery voltage for outputting a detection signal when the power switch is turned on, and sets the battery voltage after detecting the decrease in battery voltage. Is switched to the second reference voltage (> the first reference voltage) as a reference voltage for detecting the return of the signal. Since the difference between the second reference voltage and the first reference voltage is set to a level equal to or higher than the voltage at which the battery voltage self-returns from the time the power switch is turned off until the predetermined time elapses, the difference is detected during this time. No signal is output.

According to the fourth aspect of the present invention, the detection signal from the voltage detecting means is not accepted for a predetermined start-up time from the time when the power switch is turned on. Absent. In order to prohibit the reception of the detection signal, a method of not performing the detection operation itself or ignoring the detection signal is employed.

According to the invention, the capacitor starts charging when the power switch is turned on.
When the output voltage of the capacitor reaches a predetermined level, reception of a detection signal is performed. On the other hand, when the power switch is turned off, discharging of the charged electric charge is started. When the output voltage of the capacitor due to the discharge drops to a predetermined level, the detection signal is not received.

According to the invention, the setting of the second reference voltage is canceled by the reference voltage switching means when a predetermined time elapses after the power switch is turned off. , The first reference voltage is set again.

Further, according to the present invention, the reference voltage switching means holds the setting of the second reference voltage until the battery voltage exceeds the second reference voltage. If the remaining capacity is already insufficient at that time, the detection signal is output immediately.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 1 is a circuit diagram showing a battery application device to which the first embodiment of the battery remaining capacity notification device is applied.

In this battery application device, a switch 1 is connected to a battery 1.
A load 3 such as a motor or an internal constant voltage source is connected through the switch. When the switch 2 is turned on, the load 3 operates.

The voltage detection circuit 4 has an input terminal 4a connected to the battery 1
And detects the battery voltage Vb,
The detected battery voltage Vb and a preset reference voltage Vth
And when the battery voltage decreases and Vb ≦ Vth,
A high level signal is output from the output terminal 4b.

When the ON signal of the switch 2 is input to the input terminal 5a, the off-delay timer 5 outputs the output terminal 5b.
Output a high-level signal. Further, when the switch 2 is turned off and the on signal of the switch 2 is switched to the off signal, from this point in time, for a predetermined time τ1,
This is to hold a high-level signal from the output terminal 5b.

The gate circuit 6 outputs a low-level signal when both input signals to both input terminals are at a high level. The display circuit (LED) 7 has an anode connected to the positive electrode of the battery 1 via the current limiting resistor, a cathode connected to the output terminal of the gate circuit 6, and a low-level signal output from the gate circuit 6. A current flows through the device to light it.

Next, the operation will be described with reference to FIG. When the switch 2 is turned on to start using the device, a high level signal is output from the output terminal 5b of the off delay timer 5. When the use of the device is continued and the battery voltage Vb gradually decreases and Vb ≦ Vth, and a high-level signal is output from the output terminal 4b of the voltage detection circuit 4 (time T1 in FIG. 2), the gate is turned on. A low level signal is output from the circuit 6, and the LED 7 lights up.

Thereafter, when the switch 2 is turned off to stop using the device, the output signal level of the output terminal 5b of the off-delay timer 5 is switched from high level to low level after a predetermined time τ1 (FIG. 2). Medium, T2). At this point, the output signal level of the output terminal of the gate circuit 6 is switched from low level to high level,
ED7 turns off.

As described above, even after the switch 2 is turned off and the use of the device is stopped, the LED 7 is kept turned on for a predetermined time τ1, so that the user can be assured that the remaining capacity of the battery has decreased. Can be notified.

Next, a second embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 3 is a circuit diagram showing a battery application device to which the second embodiment of the battery remaining capacity notification device is applied. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Generally, in a battery-applied device having a small load current, there is no large difference in the battery voltage when the switch 2 is turned on and off. However, in a battery application device having a large load current, the battery voltage Vb is restored by turning off the switch 2 and the reference voltage Vt, as indicated by P1 in FIG.
h may be exceeded. In particular, when the remaining capacity at the time of performing display is small, the internal resistance of the battery 1 is increased, so that this phenomenon tends to appear remarkably. in this case,
In the first embodiment, the output signal level of the output terminal 4b of the voltage detection circuit 4 switches from high level to low level,
The LED 7 is turned off despite the predetermined time τ1.

The second embodiment improves this point.
A latch circuit 11 is interposed between the voltage detection circuit 4 and the gate circuit 6. When the ON signal of the switch 2 is input to the reset terminal R, the latch circuit 11 outputs the signal to the input terminal S.
The signal input from the voltage detection circuit 4 is directly output from the output terminal Q. On the other hand, when the input signal of the switch 2 to the reset terminal R is switched from the on signal to the off signal, the latch is performed only when the high level signal is output from the voltage detection circuit 4 to the input terminal S, and the output terminal Q It outputs a high level signal.

As described above, the high-level signal of the voltage detection circuit 4 is latched by the latch circuit 11 when the switch 2 is turned off and is input to the gate circuit 6.
As shown at P1 in FIG. 7A, even if the battery voltage returns after the switch 2 is turned off and Vb> Vth, the LED 7
Does not go out.

The reason why the latch function is stopped when the switch 2 is turned on is that although the remaining capacity of the battery 1 is still sufficient, a temporary voltage drop when the load temporarily increases. (P2 in FIG. 4A) and when the switch 2 is turned on, when a voltage drop occurs, this is detected to prevent latching. Thereby, it is possible to prevent the LED 7 from being erroneously turned on due to a temporary voltage drop.

Next, a third embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 5 is a circuit diagram showing a battery application device to which the third embodiment of the battery remaining capacity notification device is applied. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The voltage detection circuit 41 of the third embodiment detects the battery voltage Vb, compares it with the reference voltage Vth, and outputs a high-level signal when Vb ≦ Vth, as in the first embodiment. However, the configuration is such that the level of the reference voltage Vth is switched according to the on / off state of the switch 2.

FIG. 6 is a circuit diagram showing a configuration of the voltage detection circuit 41. Input terminal 41a connected to the positive electrode of battery 1
Is connected to one input terminal 74a of the comparator IC 74, and is connected to the reference voltage generator 7 via a constant current source.
3 is connected. The reference voltage generating unit 73 is connected to the switch 72 via a series circuit of the voltage dividing resistors R1 and R2.
74 is connected to the other input terminal 74b. The switch 72 turns on and off in conjunction with turning on and off of the switch 2.

The reference voltage Vth to the input terminal 74b of the comparator IC 74 is such that when the switch 2 is off, the switch 72 is also off and the voltage generated by the reference voltage generator 73 is directly input. 72 is also on, the voltage generated by the reference voltage generator 73 is divided by the voltage dividing resistor R
Switching is performed by inputting the voltage divided by R1 and R2. The voltage generated by the reference voltage generator 73 is set higher than the return voltage of the battery 1. The voltage dividing ratio of the voltage dividing resistors R1 and R2 is set such that a divided voltage capable of detecting a voltage drop due to a decrease in the remaining capacity of the switch 2 is obtained.

Next, the operation will be described with reference to FIG. 7. Since the switch 72 is on while the switch 2 is turned on, that is, while the device is in use, the voltage generated by the reference voltage generator 73 is divided. The value divided by the piezoresistors R1 and R2 is compared with the battery voltage Vb as a reference voltage Vth.
When the voltage becomes Vth (T1 in FIG. 7), a high-level signal is output from the voltage detection circuit 41.

When the switch 2 is turned off and the use of the device is stopped, the switch 72 is turned off, and the voltage generated by the reference voltage generator 73 becomes the reference voltage Vth. It rises (P1 in FIG. 7).

Therefore, as shown at P2 in FIG.
Even if the battery voltage Vb returns after the use of the device is stopped, the voltage does not exceed the reference voltage Vth, so that the LED 7 does not go out halfway.

Next, a fourth embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 8 is a circuit diagram showing a battery application device to which the fourth embodiment of the battery remaining capacity notification device is applied. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The output terminal 4b of the voltage detection circuit 4 is connected to the input terminal 5 of the off-delay timer 51 via the switch 21.
The output terminal 51 b of the off-delay timer 51 is connected to the cathode of the LED 7.

The switch 21 is turned on and off in conjunction with the turning on and off of the switch 2. The switch 21 is turned on only while the switch 2 is on, and the output signal of the voltage detection circuit 4 is sent to the off-delay timer 51. It is designed to communicate.

The off-delay timer 51 is connected to the input terminal 5
When a high level signal is input to 1a, the output terminal 51b
Output a low-level signal from. Further, the output signal level is switched from low level to high level after a predetermined time τ1 from the point when the input signal to the input terminal 51a is switched from high level to low level.

Next, the operation will be described with reference to FIG. 9. If the battery voltage Vb drops to Vb.ltoreq.Vth while the switches 2 and 21 are on, that is, while the apparatus is in use (T1 in FIG. 9). ), The voltage detection circuit 4 outputs a high-level signal, the off-delay timer 51 outputs a low-level signal, and the LED 7 lights up.

When the switch 2 is turned off to stop using the device, the switch 21 is turned off and the input terminal of the off-delay timer 51 is opened, so that the battery voltage Vb after the switch 2 is turned off. Irrespective of the return, the lighting of the LED 7 can be surely continued for the predetermined time τ1.

Next, a fifth embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 10 is a circuit diagram showing a battery application device to which the fifth embodiment of the battery remaining capacity notification device is applied. The first
The same components as those of the fourth to fourth embodiments are denoted by the same reference numerals, and description thereof is omitted.

In the fifth embodiment, a series circuit including voltage dividing resistors R11 and R12 and a switch 22 is connected in parallel with the battery 1. The switch 22 turns on the switch 2,
It turns on and off in conjunction with turning off.

The voltage detection circuit 42 has an output terminal directly connected to the input terminal of the off-delay timer 51, an input terminal connected to the connection point of the voltage dividing resistors R11 and R12, and the battery voltage Vb or its divided voltage Vr. Is entered. Then, the input voltages Vb and Vr are compared with the reference voltage Vth, and a high-level signal is output when Vb ≦ Vth or Vr ≦ Vth.

The reference voltage Vth and the divided voltage Vr of the voltage dividing resistors R11 and R12 are relatively set so as to detect that the remaining capacity of the battery 1 has decreased and the battery voltage Vb has decreased. Things.

Next, the operation will be described with reference to FIG. 11. If the battery voltage Vb drops and the divided voltage Vr becomes Vr.ltoreq.Vth while the switch 2 and the switch 22 are on, that is, while the apparatus is in use ( In FIG. 11, T1), the voltage detection circuit 42 outputs a high-level signal, the off-delay timer 51 outputs a low-level signal, and the LED 7 is turned on.

When the switch 2 is turned off to stop using the device, the switch 22 is turned off, and the voltage detection circuit 42 is substantially equal to the battery voltage Vb via the resistor R11 (the voltage drop at the resistor R11 is subtracted). A) Voltage is input. For this reason, normally, Vb> Vth, so that
The output signal of the voltage detection circuit 42 switches to a low level. The off-delay timer 51 outputs a low-level signal for a predetermined time τ1 from this time,
The lighting of the ED 7 can be continued.

When the battery voltage Vb further decreases during use of the device and becomes Vb ≦ Vth, the output signal level of the voltage detection circuit 42 remains high even after the switch 2 is turned off. The delay timer 51 may continue to output the low level signal, and the LED 7 may not be turned off. To prevent this, the reference voltage Vth is
7 may be set to be equal to or lower than the forward voltage of the LED 7 so that the LED 7 itself cannot be lit. In addition, as the display circuit 7, L
When a member other than the ED is used, the reference voltage Vth may be set to be equal to or lower than the operating voltage of the member.

Next, a sixth embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 12 is a circuit diagram showing an off-delay timer of a battery application device to which the sixth embodiment of the battery remaining capacity notification device is applied. The same components as those in the fourth and fifth embodiments are denoted by the same reference numerals, and description thereof will be omitted.

The sixth embodiment is different from the fourth and fifth embodiments in that when the device is in use, that is, when the switch 2 is turned on, the timer function of the off-delay timer 51 is not operated and the switch 2 is turned off. The timer function is activated only when the timer function is performed.

The off-delay timer 51 is connected to the input terminal 5
1a, between the output terminal 51b, a resistor R5 and a capacitor C5.
And the inverter 8 are connected in series. Also, the switch 2 is turned on in parallel with the resistor R5,
A switch 24 that turns on and off in conjunction with turning off is connected.

Next, the operation will be described with reference to FIG. 13. Since the switch 24 is on while the switch 2 is on, that is, while the device is in use, the off-delay timer 51 uses the voltage detection circuit 4 ( Since the low-level signal input from 42) is inverted by the inverter 8 and a high-level signal is output, the LED 7 is turned off.

When the battery voltage Vb decreases and a high-level signal is input from the voltage detection circuit 4 (42) (T1 in FIG. 13), the capacitor C5 is instantaneously charged, and the high-level signal is supplied to the inverter. The signal is inverted at 8 and a low level signal is output, and the LED 7 is turned on.

Next, when the switch 2 is turned off and the use of the device is stopped, the switch 24 is also turned off and the input of the high-level signal from the voltage detection circuit 4 (42) is stopped. Therefore, as indicated by P1 in FIG. 13B, the electric charge charged in the capacitor C5 is gradually discharged through the resistor R5, so that the LED 7 is turned off for a time τ1 until the threshold level of the inverter 8 reaches T2. Lighting can be continued.

As described above, the timer function of the off-delay timer 51 is not operated while the switch 2 is on, that is, while the device is in use. Therefore, when the battery voltage Vb drops temporarily during use of the device. However, it is possible to prevent the lighting of the LED 7 from continuing for the time τ1.

Next, a seventh embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 14 is a circuit diagram showing a battery application device to which the seventh embodiment of the battery remaining capacity notification device is applied. The first
The same components as those in the embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The voltage detection circuit 43 has an input terminal 43a connected to the positive electrode of the battery 1 via the switch 25, and can detect the battery voltage Vb. Then, the detected battery voltage Vb is compared with the reference voltage Vth, and when Vb ≦ Vth, a low-level signal is output from the output terminal 43b.

The display circuit (LED) 7 has an anode connected to the positive electrode of the battery 1 via the current limiting resistor and the switch 25, and a cathode connected to the output terminal 43b of the voltage detection circuit 43.
And the switch 25 is on and the output terminal 4
When the low-level signal is output from 3b, the light is turned on.

The off-delay timer 52 is connected to the output terminal 5
The on / off control of the switch 25 is controlled by the signal output from the switch 2b. The on / off signal of the switch 2 is input to the input terminal 52a, and the switch 2 is turned on and turned off from on. The control is such that the ON state of the switch 25 is maintained for a predetermined time τ1.

Next, the operation will be described with reference to FIG. 15. When the switch 2 is turned on, that is, while the device is in use, the switch 25 is turned on, and when the battery voltage Vb falls and Vb ≦ Vth, (T1 in FIG. 15), the voltage detection circuit 43 outputs a low level signal, and the LED 7 is turned on.

When the switch 2 is turned off to stop using the device, the switch 25 is kept on for a predetermined time τ1 from this point.
Keeps lighting, and when the switch 25 is turned off, the power supply is cut off and the LED 7 is turned off.

Accordingly, it is possible to reliably notify the user of the decrease in the remaining capacity of the battery. Further, after the lapse of the predetermined time τ1, the operation of the voltage detection circuit 43 is stopped, so that the current consumption when the device is not used can be reduced.

To prevent the battery voltage Vb from returning after the switch 2 is turned off,
The latch circuit 11 (FIG. 3) is interposed between the voltage detection circuit 43 and the LED 7 to hold the output signal, or the voltage detection circuit 43 is configured as shown in FIG.
It is sufficient to switch th.

Next, an eighth embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 16 is a circuit diagram showing a battery application device to which the eighth embodiment of the battery remaining capacity notification device is applied. The first
The same components as those in the embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The off-delay timer 5 outputs a high-level signal from the time when the switch 2 is turned on to a predetermined time τ1 after the switch is turned off. During this time, the transistor Q1 is turned on, and power is supplied from the battery 1 to the voltage detection circuit 44. I do. The voltage detection circuit 44 operates while receiving power (see FIG. 17).
(Medium, signal at point A), detection operation is enabled. This voltage detection circuit 44 includes a comparator IC 44
1. A reference voltage generating unit 442 and a transistor 443, and voltage dividing resistors R21 and R22 connected in series.
And a resistor R23 connected in parallel with the resistor R22. The middle point of the voltage dividing resistors R21 and R22 is a comparator IC.
441 is connected to one input terminal, and the other input terminal is connected to a reference voltage generator 442. Reference voltage generator 4
Reference numeral 42 is set to a level Vtho for detecting a drop in the battery voltage Vb.

The transistor 443 is connected in series with the resistor R23, and while the comparator IC 441 is outputting a low level, the battery voltage Vb is connected to the resistors R21 and R2.
2 is input to the input terminal of the comparator IC 441. On the other hand, while the comparator IC 441 is outputting a high level, it is turned on, the resistors R22 and R23 are connected in parallel, and the battery voltage Vb is changed to the resistor R21. And the resistance of
The voltage divided by the parallel combined resistance value of the resistors R22 and R22 is input to the input terminal of the comparator IC441. Switching the voltage division ratio in this manner can be equivalent to switching and changing the reference voltage for relatively detecting a decrease in battery voltage.

That is, if the output terminal of the comparator IC441 is at a low level, the equivalent reference voltage Vth1
Becomes Vtho · (R21 + R22) / R21. On the other hand, if the output terminal of the comparator IC 441 is at a high level, the equivalent reference voltage Vth2 becomes Vtho · (R2
1 + R22 // R23) / R21. In addition, R22 //
R23 represents a parallel combined resistance value of the resistors R22 and R23. In addition, there is a relationship of Vth1 <Vth2, and the resistance R
Reference numeral 23 denotes a resistor whose resistance value is set so that Vth2−Vth1 is equal to or higher than a level at which the voltage of the battery 1 self-recovers and rises for a predetermined time τ1 after the switch 2 is turned off as described later. Has been adopted.

The transistor 61 is connected in series to the LED 7, and its base is connected to the output terminal of the comparator IC 441. It turns on while the comparator IC 441 outputs a high-level output signal,
The ED 7 is turned on.

Next, the operation will be described with reference to FIG. 17. When the switch 2 is turned on, that is, while the load 3 is driven, the voltage detection circuit 44 operates, and first, the battery voltage drops to the reference voltage Vth1. (I.e., whether the divided value of the battery voltage has become equal to or less than the reference voltage Vtho). When the battery voltage drops below the reference voltage Vth1 (T1 in FIG. 17), the comparator IC44
1 outputs a high level, turns on the transistor 61 to turn on the LED 7, and outputs the transistor 443.
Is turned on to switch the reference voltage from Vth1 to Vth2. Thereafter, when the switch 2 is turned off, the battery 1
Is self-recovered and rises. However, since the level of Vth2 is set to be equal to or higher than the self-recovery level, the comparator IC 441 does not invert to the low level at least during the predetermined time τ1. Is τ1
Retained for time only.

As described above, with a simple circuit configuration without using a latch circuit, the voltage rise accompanying the self-recovery of the battery voltage after the switch 2 is turned off can be maintained for a predetermined time τ1.
Can be ensured, so that the user can be reliably notified that the remaining capacity of the battery has decreased.

Next, a ninth embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 18 is a circuit diagram showing a battery application device to which the ninth embodiment of the battery remaining capacity notification device is applied. The same components as those in the first and eighth embodiments are denoted by the same reference numerals, and description thereof will be omitted.

The above-described eighth embodiment has no problem for a device in which the starting current of the load 3 when the switch 2 is turned on is not particularly large, but the starting current such as a motor is several times larger than the steady-state current. In such devices, the battery voltage drops below the reference voltage Vth1 when the switch is turned on, and the detection state is continued by the reference voltage hysteresis thereafter.
There is a problem that the LED 7 may be lit and held despite the remaining capacity of the battery. The ninth embodiment solves such a problem.

When the switch 2 is turned on, the on-delay timer 9 outputs a high-level signal with a delay of a predetermined time τ2, and returns the output to a low level when the switch 2 is turned off (A in FIG. 19). The output signal is input to the off-delay timer 5. As described above, by not supplying power to the voltage detection circuit 44 for the time τ2 required for starting the load 3, a decrease in the battery voltage due to the starting current (FIG. 19D, at time T0) is prevented. Erroneous detection is eliminated. As a method of not accepting the detection of the decrease in the battery voltage as described above, in addition to the method of setting the start-up period τ2, a delay circuit that delays the rise due to the power supply is provided in the voltage detection circuit 44. You may.

As described above, in the eighth and ninth embodiments, the power supply to the voltage detection circuit 44 is stopped after the predetermined time τ1, and the reference voltage is automatically returned to Vth1, so that it is assumed that there is a certain use. In some cases, even if the erroneous detection is performed and the erroneous display is performed even though the remaining battery capacity is sufficient, the operation can be returned to the normal operation at the next use, and the erroneous display can be suppressed only once.

FIG. 20 shows an example of a circuit configuration for realizing the on-delay timer 9 and the off-delay timer 5 shown in FIG. In FIG. 20, to one input terminal of the comparator IC91 is connected to a constant voltage generating circuit 92 for outputting a constant voltage V _SL, to the other input terminal, the transistor Q3 which operates by on-off signal from the switch 2 is They are connected via a time constant circuit composed of a resistor R30 and a capacitor C30. A constant current source 93 is connected to the other input terminal of the comparator IC91. The capacitor C30 is arranged to generate the constant voltage V _SL more terminal voltages Vu by the constant current source 93.

The operation of this circuit configuration will be described with reference to FIG. 21. When the switch 2 is left, the capacitor C30 receives a current from the constant current source 93 and _reaches a predetermined high level Vu (> V _SL ). Therefore, the output terminal of the comparator IC91 is at a low level. Therefore, the transistor Q1 illustrated in FIG. 18 is turned off, and the driving of the voltage detection circuit 44 is stopped. Thereafter, the switch 2 is turned on and the transistor Q3
When a high-level ON signal is inputted to the base of the transistor Q3, the transistor Q3 is turned on. When the transistor Q3 is turned on, the charge stored in the capacitor C30 is discharged through the resistor R30. This discharging is performed at a level Vd at which the charging current from the constant current source 93 and the discharging current are in an equilibrium state.
(<V _SL ). Therefore, switch 2
After There is turned on, the terminal voltage of the capacitor C30 from Vu to time drops to V _SL .tau.2 (i.e. starting time of the load 3), the comparator IC91 maintains the low level output, and thereafter inverted to a high level , Transistor Q
1 is turned on to enable the voltage detection circuit 44 to operate.

On the other hand, when the switch 2 is turned off and the transistor Q3 is turned off, the capacitor C30 stops discharging and starts charging only with the charging current from the constant current source 93. Therefore, the terminal voltage of the capacitor C30 gradually increases from Vd to Vu. Capacitor C30
The terminal voltage after off of the switch 2, elapsed τ1 hours exceeds the constant voltage V _SL, thereby so inverts the comparator IC91 to a low level, the operation of the voltage detection circuit 44 is stopped. As described above, by changing the charging / discharging current of one capacitor C30, both the on-delay and the off-delay can be performed with a simple circuit configuration.

Next, a tenth embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 22 is a circuit diagram showing a battery application device to which the tenth embodiment of the battery remaining capacity notification device is applied. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The voltage detection circuit 45 has the same internal circuit configuration as that of the eighth and ninth embodiments, except that power is directly supplied from the battery 2. Therefore, the voltage detection circuit 4
Reference numeral 5 indicates that after the reference voltage is changed from Vth1 to Vth2, the set state of the reference voltage Vth2 is maintained until the battery is replaced or the battery is charged.

Next, the operation will be described with reference to FIG. 23. At a certain time T01, the switch 2 is turned on and the eighth
As shown in the embodiment, the battery voltage Vb and the reference voltage Vth1
Is compared with the reference voltage Vth1 at time T1.
When it falls below, lighting of the LED 7 is started. The lighting of the LED 7 is continued for a predetermined time τ1 after the switch 2 is turned off, and is turned off at time T2. Note that the reference voltage has been switched from Vth1 to Vth2 at the time T1. Further, the battery voltage is self-recovered to some extent by turning off the switch 2, but as described in the eighth embodiment, even if the recovery level exceeds the reference voltage Vth1,
It is equal to or lower than the reference voltage Vth2.

Thereafter, at the time T02, when the next use is started, the battery voltage is compared with the reference voltage Vth2. Therefore, the voltage detection circuit 45 can immediately detect a decrease in the remaining capacity of the battery, and the LED 7 can notify that effect. In FIG. 23, a time τ3 indicates a time required from the time when the switch 2 is turned on to the time when the remaining capacity is reduced (that is, the notification by the LED 7) when the reference voltage is returned to Vth1. In this way, by keeping the reference voltage at Vth2 once the decrease in the remaining capacity is confirmed, it is possible to provide an effective notification to that effect at the next use at the same time as the start of use, so that the time lag τ3 Can be eliminated.

Next, an eleventh embodiment of the battery remaining capacity informing device according to the present invention will be described with reference to FIGS. FIG. 24 is a circuit diagram showing a battery application device to which the eleventh embodiment of the battery remaining capacity notification device is applied. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, the voltage detection circuit 4 and the LED
A time constant circuit composed of a resistor R40 and a capacitor C40 and a NOR circuit 62 are interposed between the two. The output terminal of the voltage detection circuit 4 is connected to one input terminal of the NOR circuit 62, and the voltage detection circuit 4 is connected to the other input terminal via the time constant circuit. The NOR circuit 62 has a threshold voltage Vthx. On the other hand, the capacitor C40 constituting the time constant circuit is charged to at least the level of Vthx or more by the input of the high level signal from the voltage detection circuit 4, and from the state charged to the saturation state to the resistance R40 When the discharge is started via the voltage Vt, the level Vt
hx.

Next, the operation will be described with reference to FIG. Now, assuming that the switch 2 is turned on at the time T0 and the battery voltage Vb drops below the detection level Vth for a short time τ4 due to the starting current at this time, τ
A high level signal is output from the voltage detection circuit 4 for only 4 hours. The high level signal for this τ4 time is output from the NOR circuit 6
2, the output of the NOR circuit 62 is inverted to a low level, and the LED 7 starts to light. On the other hand, it is assumed that the capacitor C40 is charged for the output time τ4 of the high-level signal, and that the terminal voltage of the capacitor C40 has risen to a level slightly above the level Vthx as shown by the signal level at point B in FIG.
When the time τ4 ends, the capacitor C40 starts discharging with a required time constant via the resistor R40, and drops to the level Vthx within τ5 hours from the start of discharging. Accordingly, the output side of the NOR circuit 62 is maintained at the low level for the time period (τ4 + τ5) from the time point T0, whereby the LE circuit
D7 turns on only for (τ4 + τ5) time.

On the other hand, the use of the load 3 is continued, the remaining capacity of the battery decreases, and the battery voltage Vb becomes lower than the reference voltage Vt at the time T1.
When the voltage falls below h, the NOR circuit 62 outputs a low level and turns on the LED 7 in the same manner as described above. At this time,
When the high-level signal output from the voltage detection circuit 4 continues for a time longer than the time constant of the time constant circuit,
The terminal voltage of the capacitor C40 is saturated (in FIG. 25, T
11). In this state, when the switch 2 is turned off, the capacitor C40 starts discharging from the saturation voltage level, so that the terminal voltage decreases to Vthx by τ.
It takes one hour, so that the notification of the decrease in the remaining capacity of the battery is held for τ1 after the switch 2 is turned off.

Note that the sudden voltage drop is not limited to the time of starting,
It may occur at any time due to a sudden load change during use, etc., but such a case can be dealt with.

As described above, during use, the battery voltage suddenly drops, and even if an erroneous notification is given, the display can be completed in a short time corresponding to the fluctuation time, and the remaining capacity can be reduced. When the detection is correctly performed, the notification is continued for τ1 time. Therefore, the time width of the voltage drop is measured to eliminate the erroneous notification, and the detection signal is output after judging the presence or absence of the correct / error detection from the measurement result. Compared with the case of such a configuration, the circuit configuration can be simplified, and quick display can be performed without generating a time lag.

[0091]

As described above, according to the first aspect of the present invention, when the battery voltage detected during the operation of the device falls below the preset reference voltage, a notification signal is output, and this notification signal is output. The output is continued until a predetermined time elapses from the stop of the operation of the device, and the notification unit is operated in response to the notification signal, so that the user can be reliably notified of the decrease in the remaining battery capacity. Further, even when the battery voltage is restored after the operation of the device is stopped, the user can be reliably notified of the decrease in the remaining battery capacity regardless of the battery voltage level.

According to the second aspect of the present invention, the detection signal is output only for a period corresponding to the period when the battery voltage has dropped below the reference voltage, and the notification is performed only during that period, so that the notification timing can be expedited. In addition, in the case of false detection,
Since the notification is canceled in a very short time, the determination is easy. Further, it is possible to realize the detection with an extremely simple circuit configuration as compared with a circuit configuration in which whether the detection is correct or not is determined based on the detection time width and the notification is performed if the detection is normal.

According to the third aspect of the present invention, when the battery voltage detected during the operation of the device becomes equal to or lower than the preset reference voltage, a notification signal is output, and the output of the notification signal is changed to a predetermined value after the operation of the device is stopped. The operation is continued until the time elapses, and the notification unit is operated in response to the notification signal, so that the user can be reliably notified of the decrease in the remaining capacity of the battery. Further, when the power switch is turned on, the first reference voltage is switched and set as a reference voltage for detecting a drop in the battery voltage for outputting a detection signal, and after detecting the drop in the battery voltage, a reference voltage for detecting the return of the battery voltage. As the second reference voltage (> first
The reference voltage is switched and set, and the difference between the second reference voltage and the first reference voltage is set to a level at which the battery voltage self-recovers during a predetermined time after the power switch is turned off. During this time, it is possible to prevent the detection signal from being output erroneously, and it is possible to reliably notify the user of the decrease in the remaining capacity of the battery.

According to the fourth aspect of the present invention, since the detection signal from the voltage detecting means is not accepted for a predetermined start-up time after the power switch is turned on, erroneous detection due to a voltage drop at the start-up is prevented. Can be.

According to the fifth aspect of the present invention, both the activation time signal after the power switch is turned on and the notification holding time signal after the power switch is turned off are easily generated while having a simple circuit configuration of one capacitor. be able to.

According to the sixth aspect of the invention, the setting of the second reference voltage is canceled when a predetermined time elapses after the power switch is turned off, so that a decrease in the battery voltage can be reliably detected at the next use of the load. be able to.

According to the seventh aspect of the present invention, the battery voltage is set to the second
Since the setting of the second reference voltage is maintained until the reference voltage is exceeded, when the remaining capacity is already insufficient at the start of the next use of the load, the detection signal can be output immediately, and You can get accurate information.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a battery application device to which a first embodiment of a battery remaining capacity notification device according to the present invention is applied.

FIG. 2 is a diagram showing the operation of the battery application device of the first embodiment.
(A) is the operation of the switch 2, (b) is the signal level at point A in FIG. 1, (c) is the transition of the battery voltage, (d) is the signal level at point B in FIG. 1, and (e) is the display circuit. 7 shows the operation.

FIG. 3 is a circuit diagram showing a battery application device to which a second embodiment of the battery remaining capacity notification device according to the present invention is applied;

FIG. 4 is a diagram showing the operation of the battery application device of the second embodiment.
3 (a) shows the transition of the battery voltage, FIG. 3 (b) shows the signal level at point B in FIG. 3, FIG. 3 (c) shows the signal level at point C in FIG. 3, FIG. Signal level at point A,
(F) shows the operation of the display circuit 7.

FIG. 5 is a circuit diagram showing a battery application device to which a third embodiment of the battery remaining capacity notification device according to the present invention is applied.

FIG. 6 is a circuit diagram showing a voltage detection circuit 41 of FIG. 5;

FIG. 7 is a diagram showing the operation of the battery application device of the third embodiment.
(A) is the operation of the switch 2, (b) is the transition of the battery voltage,
(C) shows an output signal of the voltage detection circuit 41.

FIG. 8 is a circuit diagram showing a battery application device to which a fourth embodiment of the battery remaining capacity notification device according to the present invention is applied.

FIG. 9 is a diagram showing the operation of the battery application device of the fourth embodiment.
8A shows the operation of the switch 2 (21), and FIG.
(C) is the signal level at point B in FIG.
(D) shows the operation of the display circuit 7.

FIG. 10 is a circuit diagram showing a battery application device to which a fifth embodiment of the battery remaining capacity notification device according to the present invention is applied.

11A and 11B are diagrams showing the operation of the battery application device according to the fifth embodiment, wherein FIG. 11A shows the operation of the switch 2 (22), FIG. 11B shows the transition of the battery voltage, and FIG. 11C shows the output of the voltage detection circuit 42. The signal level, (d), shows the operation of the display circuit 7.

FIG. 12 is a circuit diagram showing an off-delay timer 51 of a battery application device to which a sixth embodiment of the battery remaining capacity notification device according to the present invention is applied.

13A and 13B are diagrams showing the operation of the battery application device of the sixth embodiment, where FIG. 13A is a point A in FIG. 12, FIG. 13B is a point B in FIG.
(C) shows the signal level at point C in FIG.

FIG. 14 is a circuit diagram showing a battery application device to which a seventh embodiment of the battery remaining capacity notification device according to the present invention is applied.

15A and 15B are diagrams showing the operation of the battery application device of the seventh embodiment, wherein FIG. 15A shows the operation of the switch 2 and FIG.
(C) shows the operation of the display circuit 7.

FIG. 16 is a circuit diagram showing a battery application device to which an eighth embodiment of the battery remaining capacity notification device according to the present invention is applied.

17A and 17B are diagrams showing the operation of the battery applied device of the eighth embodiment, where FIG. 17A shows the operation of the switch 2, FIG. 17B shows the signal level at point A in FIG. 16, and FIG. 17C shows the battery voltage and reference voltage. (D) shows the operation of the display circuit 7.

FIG. 18 is a circuit diagram showing a battery application device to which a ninth embodiment of the battery remaining capacity informing device according to the present invention is applied.

19A and 19B are diagrams showing the operation of the battery application device of the ninth embodiment, wherein FIG. 19A shows the operation of the switch 2, FIG. 19B shows the signal level at point A in FIG. 18, and FIG. Signal level,
(D) shows the transition of the battery voltage, and (e) shows the operation of the display circuit 7.

FIG. 20 is a circuit diagram showing a circuit configuration including an on-delay timer and an off-delay timer applied to the ninth embodiment.

FIG. 21 is a diagram for explaining the operation of the circuit diagram of FIG. 20;
(A) shows the operation of the switch 2, (b) shows the voltage level at point A in FIG. 20, and (c) shows the state of the voltage detection operation.

FIG. 22 is a tenth embodiment of the battery remaining capacity informing device according to the present invention.
It is a circuit diagram showing the battery application equipment to which an example is applied.

23A and 23B are diagrams showing the operation of the battery application device of the tenth embodiment, where FIG. 23A shows the operation of the switch 2, FIG. 23B shows the signal level at point A in FIG. 22, FIG. (D) shows the operation of the display circuit 7.

FIG. 24 is an eleventh embodiment of the battery remaining capacity informing device according to the present invention.
It is a circuit diagram showing the battery application equipment to which an example is applied.

25A and 25B are diagrams showing the operation of the battery applied device of the eleventh embodiment, wherein FIG. 25A shows the operation of the switch 2, FIG. 25B shows the transition of the battery voltage, FIG. 25C shows the signal level at point A in FIG. (D) is FIG.
4 shows the signal level at point B, and (e) shows the operation of the display circuit 7.

FIG. 26 is a circuit diagram showing a battery application device to which a conventional battery remaining capacity notification device is applied.

FIG. 27 is a diagram showing the operation of a conventional battery application device.
(A) shows the operation of the switch 102, (b) shows the transition of the battery voltage, and (c) shows the operation of the display circuit 105.

[Explanation of symbols]

Reference Signs List 1 battery 2 switch (power switch) 3 load 4, 41, 42, 43, 44, 45 voltage detection circuit (voltage detection means) 5, 51, 52 off-delay timer (control means) 6 gate circuit (control means) 61 transistor 62 NOR circuit 7 Display circuit (notifying means) 8 Inverter 9 On delay timer 11 Latch circuit (Holding means) 22, 24, 25, 72 Switch 73, 442 Reference voltage generator 74, 441, 91 Comparator IC C5 Capacitor R1, R2 , R11, R12, R21, R22, R23
Voltage dividing resistors Q1, Q3, 443 Transistors R30, R40 Resistors forming a time constant circuit C30, C40 Capacitors forming a time constant circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01R 31/36 G01R 19/165

Claims (7)

(57) [Claims] 1. A battery application device interposed between a battery and a load and having a power switch for turning on and off the operation of the device, detecting the battery voltage, and detecting the detected battery voltage with a preset reference voltage. Voltage detecting means for outputting a detection signal at the following times: outputting a notification signal when the detection signal is output when the power switch is on, and a predetermined signal after the power switch is switched from on to off Control means for holding the output of the notification signal until time elapses, and notification means for operating in response to the notification signal, wherein the control means is configured to control when the power switch is off.
The reference voltage level for changing the reference voltage to a higher level
When the power switch is on
Output a control signal to the power switch.
After switching to, the above control
While continuing to output the signal, the notification signal
While both the detection signal and the control signal are being output,
A battery remaining capacity informing device, which is adapted to output . 2. A remaining capacity notification unit battery according to claim 1 Symbol mounting, that the battery voltage is an amount of time corresponding to the period of time that falls below the reference voltage and outputs the detection signal, and to perform notification Characteristic battery remaining capacity notification device. 3. The apparatus is interposed between a battery and a load, and operates the device.
Battery-powered equipment that has a power switch that turns on and off
And detects the battery voltage, and detects the detected battery voltage.
Output a detection signal when the voltage is lower than the set reference voltage.
Pressure detection means and the power supply switch when the power switch is on.
When an output signal is output, an alarm signal is output and
After the power switch is switched from on to off,
Holds the output of the above notification signal until the fixed time elapses
Control means, and a notifying means that operates upon receiving the notifying signal.
The voltage detecting means detects the voltage as the reference voltage.
After the power switch is turned on, the
Set to a first reference voltage for detecting a drop in battery voltage,
After detecting the battery voltage drop, the second reference voltage (> the first reference voltage)
Pressure reference means for switching to
The second reference voltage is higher than the first reference voltage.
The time from when the power switch is turned off until the specified time elapses
In the meantime, if the battery voltage is set to a level
There remaining capacity notification device that batteries be characterized Rukoto. 4. The remaining capacity of the battery according to claim 3 , wherein said control means does not receive a detection signal from said voltage detection means for a predetermined start-up time after the power switch is turned on. Notification device. Wherein said control means comprises a capacitor starts discharging through off the power switch starts the charging by turning on the power switch, the output voltage of this capacitor outputs a signal at a predetermined level or higher 5. The apparatus according to claim 4 , wherein said detection signal is received during an output period of said signal. 6. The battery remaining capacity informing device according to claim 3 , wherein the reference voltage switching means cancels the setting of the second reference voltage when the predetermined time elapses. . 7. The reference voltage switching means, a battery according to claim 3, characterized in that the battery voltage is adapted to hold a set of the second reference voltage until it exceeds the second reference voltage Remaining capacity notification device.