JP3191330B2 - Battery status judgment circuit - 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 state determining circuit suitable for determining the state of a battery mounted on, for example, a model airplane operated by a remote controller.

[0002]

2. Description of the Related Art FIG. 4 shows an overview of a model airplane controlled by a remote controller.
Numeral 0 is a remote control transmitter for outputting the remote control signal SRC to operate the model airplane 100.

FIG. 5 shows a circuit configuration in a model airplane 100. In the figure, reference numeral 101 denotes a remote control signal SRC
Antenna. The remote control signal SRC received by the antenna 101 is transmitted to the receiver 1 including the controller.
02. Then, the receiver 102 controls the steering servomotors 103-1 to 103-1 according to the content of the remote control signal SRC.
103-n and the operation of the propeller motor 104 are controlled. 1
05 is a receiver 102 and motors 103-1 to 103-n, 10
4 is a battery serving as a power source.

[0004]

In this type of model airplane, for example, there is a model airplane in which a power circuit (motor) is turned off by detecting an absolute value of a discharge end voltage of a battery.

According to this, the motor is suddenly turned off without any warning during the flight of the model airplane, so that the propulsion force is lost and the aircraft is stalled, often causing damage to the aircraft.

[0006] In order to eliminate this anxiety, means for controlling the flight time using a stopwatch or the like is taken.

However, the flight time depends on the type of battery,
It changes depending on the charging status, usage history, consumption status (operation method) and the like.

[0008] For this reason, the time is controlled by the time of the inner ring, and it cannot be expected that the battery will always be able to fully use its capacity.

FIG. 6 shows a discharge curve of the battery. Curves b and c are discharge curves when used for a large power consumption like a model airplane. Curve b is an example when the internal resistance is small, and curve c is an example when the internal resistance is large. When the internal resistance is large, the voltage value is lower than when the internal resistance is small because the voltage drop is large. Note that a curve a is a discharge curve when used for a device with low power consumption.

Therefore, if the discharge end voltage is detected by the absolute value Vo, the time T varies between batteries having the discharge curves b and c. That is, in the battery having the discharge curve of the curve c, the capacity of the battery is not fully utilized.

In view of the above, the present invention provides a battery state discriminating circuit for accurately discriminating the discharge end voltage so as to fully utilize the capacity of the battery.

[0012]

SUMMARY OF THE INVENTION The present invention provides sampling means for sampling a battery voltage at predetermined time intervals, level change detecting means for detecting a level change width of an output signal of the sampling means, and level change detecting means. Comparing the level change width detected in step (b) with a first reference level change width of the discharge end voltage of the battery .
And comparison means, first based on the result of the first comparison means
A pulse generating means for generating a pulse signal for alarm 1;
The level change width is larger than the first reference level change width.
The level change width is compared with the second reference level change width.
Alarm exceeds the second reference level change width, a second alarm
Second comparing means for outputting a signal of
Outputs the logical sum of the output of the stage and the output of the second comparing means.
Based on the output of the OR
Operating to indicate a first alarm or a second alarm
Display means .

[0013]

[Action] In the above configuration, when the battery approaches the discharge end voltage, the level change width Ri is Na large, discrimination is that the battery according to the comparison result of the first comparison means becomes final discharge voltage near <br/> And the first alarm is displayed on the display means.
Is done. After that, when the battery reaches the discharge end voltage,
The battery is brought to the discharge end voltage by the second comparing means.
And a second warning is displayed on the display means.
You. Since the end-of-discharge voltage is determined based on the level change width of the battery voltage, the battery type, charge state,
Regardless of usage history, consumption status, etc.
Fine and accurate determination can be made.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 3 shows a circuit configuration in a model airplane 100 to which the battery state determination circuit of this example is applied. 3, parts corresponding to those in FIG. 5 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, the output voltage (battery voltage) VBA of the battery 105 is supplied to the battery state determination circuit 110. This battery state determination circuit 11
0 is configured as shown in FIG.

The battery voltage VBA is supplied to sample and hold circuits 111 and 112. The sample and hold circuits 111 and 112 are supplied with sampling pulses P1 and P2 whose phases are shifted from each other by a half cycle (see FIG. 2). That is, the sampling pulses are alternately supplied to the sample and hold circuits 111 and 112 every predetermined time τ.

The output signals of the sample and hold circuits 111 and 112 are supplied to a subtractor 113, and the subtracted signal is supplied to an absolute value circuit 114 to take an absolute value. In this case, the output signal VVD of the absolute value circuit 114 becomes the level change width of the battery voltage VBA every predetermined time τ.

The output signal VVD of the absolute value circuit 114 is supplied to a comparator 115. To the comparator 115, a signal e1 indicating a reference level change width that changes to time τ near the discharge end voltage is supplied as a comparison reference signal. When VVD <e1, a signal of low level “L” is output from comparator 115, while VVD ≧ e
When it is 1, a high level "H" signal is output.

The output signal of the comparator 115 is supplied to a blinker 116. When the output signal of the comparator 115 is at the high level “H”, the blinker 116 outputs a signal that alternately goes to the low level “L” and the high level “H” in a short cycle. When the output signal of the comparator 115 is at a low level “L”, the blinker 116 outputs a signal at a low level “L”. The output signal of the blinker 116 is supplied to one input terminal of the OR circuit 117.

The output signal VVD of the absolute value circuit 114
Is supplied to the comparator 118. Comparator 1
A signal e2 indicating a reference level change width that changes at time τ at the discharge end voltage is supplied to 18 as a comparison reference signal. When VVD <e2, a signal of low level “L” is output from the comparator 118, while VVD ≧
When it is e2, a high level "H" signal is output. The output signal of the comparator 118 is
7 is supplied to the other input terminal.

The battery voltage VBA is supplied to a comparator 119. The comparator 119 is supplied with a signal e3 that is higher than the voltage near the discharge end voltage as a comparison reference signal. From the comparator 119,
When VBA ≧ e3, a low level “L” signal is output, while when VBA <e3, a high level “H” is output.
Is output. The output signal of the comparator 119 is supplied to one input terminal of the AND circuit 120.
The OR circuit 1 is connected to the other input terminal of the AND circuit 120.
17 output signals are provided. The output signal of the AND circuit 120 is output as a battery state determination signal SCD.

In the above configuration, the battery voltage VBA
Is larger than the discharge end voltage, the comparator 1
Since the output signals 15 and 118 are at the low level “L”, the OR circuit 117 outputs a low level “L” signal, which is output as the battery state determination signal SCD.

When the battery voltage VBA becomes close to the discharge end voltage, VVD.gtoreq.e1, and the comparator 115
Since the signal of the higher level “H” is output, a signal that alternately changes to the low level “L” and the high level “H” with a shorter cycle than the blinker 116 is output, and this is output as the battery state determination signal SCD. Is done.

Further, when the battery voltage VBA becomes the discharge end voltage, VVD.gtoreq.e2, and the comparator 118 outputs a high-level "H" signal, which is output as the battery state determination signal SCD.

Immediately after the discharge of the battery is started, the change width of the battery voltage VBA becomes relatively large (shown by an arrow P in FIG. 6). Therefore, the output signal of the comparator 115 or 118 becomes a high level “H”, and the low level “L” and the high level “H” alternately change in a short cycle from the OR circuit 117, or the high level “H”. May be output. However, immediately after the start of discharging of the battery, VBA ≧ e3, and the output signal of the comparator 119 becomes low level “L”. Therefore, the output signal of the OR circuit 117 is not output as the battery state determination signal SCD. .

Returning to FIG. 3, the battery state determination circuit 1
The battery state determination signal SCD output from 10 is supplied to the light emitting circuit 121. By the light emitting circuit 121,
When the discrimination signal SCD becomes a high level “H”, a light emitting element (not shown) attached to the model airplane 100 (see FIG. 4) is controlled to emit light.

When the battery voltage VBA is higher than the discharge end voltage, the determination signal SCD is a low level "L" signal, and the light emitting element does not emit light. When the battery voltage VBA is close to the discharge end voltage, the discrimination signal SCD becomes a signal in which the low level "L" and the high level "H" change alternately in a short cycle, and the light emitting element blinks and emits light. Further, when the battery voltage VBA becomes the discharge end voltage, the determination signal SCD becomes a high level "H" signal, and the light emitting element continuously emits light.

As described above, in the present embodiment, the level change width corresponding to the cycle τ of the battery voltage VBA is compared with the reference level change widths e1 and e2 to determine that the level is near the discharge end voltage or the discharge end voltage. Is obtained, so that the discharge end voltage can be accurately determined irrespective of the battery type, charge state, usage history, consumption state, etc. Can be demonstrated. For example, the ability of the battery having the discharge curve of curve c in FIG. 6 can be sufficiently exhibited, and the variation in time with the battery having the discharge curve of curve b in FIG. 6 can be greatly reduced.

Further, since the capacity of the battery can be sufficiently exhibited as described above, in this embodiment, there is an advantage that the flight time of the model airplane 100 can be extended.

When the battery voltage VBA is close to the discharge end voltage, the light emitting element of the model airplane 100 blinks and emits light, and when the discharge end voltage is reached, the light emitting element continuously emits light. By monitoring, appropriate response measures can be taken and the model airplane can be safely returned.

A sounding circuit may be provided instead of the light emitting circuit 121 of the above-described embodiment, and a sounding element such as a buzzer may be driven by the determination signal SCD.

As shown by the broken line, the discrimination signal SCD is transmitted to the remote control transmitter 200 (see FIG. 4) via the transmitter 131 and the antenna 132, and
On the 00 side, the light emitting element or the sound emitting element can be driven by the determination signal SCD. This allows
The driver can more accurately grasp the state of the battery, and can immediately take appropriate countermeasures (steering).

In the above embodiment, the model airplane 1
Although the present invention is applied to determine the state of the battery in 00, the present invention can be similarly applied to other devices such as a camera-integrated VTR. This is effective when it is desired to detect the discharge end voltage more accurately.

[0034]

According to the present invention, it is determined whether or not the battery voltage has become close to the discharge end voltage from the level change width in the predetermined period .
Since it can be determined whether the discharge end voltage has been reached ,
The end-of-discharge voltage can be finely and accurately determined irrespective of the type, charge state, use history, consumption state, and the like of the battery, and the battery can exhibit its full potential.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a battery state determination circuit according to an embodiment.

FIG. 2 is a diagram showing a sampling pulse used in the embodiment.

FIG. 3 is a diagram showing a circuit configuration in a model airplane to which the embodiment is applied.

FIG. 4 is a diagram showing an overview of a model airplane operated by a remote controller.

FIG. 5 is a diagram showing a circuit configuration in a model airplane.

FIG. 6 is a diagram showing a discharge curve of a battery.

[Explanation of symbols]

REFERENCE SIGNS LIST 100 model airplane 102 receiver (controller) 103-1 to 103-n steering servomotor 104 propeller motor 105 battery 110 battery state determination circuit 111, 112 sample hold circuit 113 subtractor 114 absolute value circuit 115 comparator (first comparison) Means) 118 Comparator (second comparing means) 119 Comparator 116 Blinker (pulse generating means) 117 OR circuit 120 AND circuit (logical sum means) 121 Light emitting circuit VBA Battery voltage SCD Battery state discrimination signal

Claims (1)

(57) [Claims] 1. Sampling means for sampling a battery voltage at predetermined time intervals, level change detecting means for detecting a level change width of an output signal of the sampling means, and the level change width detected by the level change detecting means a first comparison means for comparing a first reference level change width of the final discharge voltage of the battery, Pal first alarm based on the result of the first comparison means
Pulse generating means for generating a pulse signal, the level change width being larger than the first reference level change width.
The above level change is compared with the second reference level change width.
If the width exceeds the second reference level change width, a second alarm is issued.
A second comparing means for outputting an information signal, an output of the pulse generating means, and an output of the second comparing means.
OR means for outputting a logical sum with a force, and a first alarm or a second alarm based on an output from the OR means.
A display means operable to display the second alarm .