JPH05289785A - Battery consumption detecting device - Google Patents

Abstract

PURPOSE:To exactly evaluate a consumed state of a battery by the same reference by deriving an end voltage in accordance with combination of input/output units which are being used at present, and comparing this end voltage and a voltage of the battery. CONSTITUTION:When input/output units U1, U2...Un are operating, or before they operate, an end voltage setting part 2 can derive the present optimal end voltage V, based on a switching state of an inputted changeover switch 1. This end voltage V is inputted to a comparing part 3, and in this comparing part 3, a voltage E of a battery 4 is inputted for comparison in advance. The comparator 3 outputs an active signal only at the time of E<V. This signal is inputted to a power source cutting-off part 5, and used for stopping all or a part of the input/output units U1, U2...Un. Accordingly, a degree of consumption of the battery is evaluated exactly by the same reference, irrespective of which combination of the input/output units U1, U2...Un is operating, and supply of a power source to the input/output units U1, U2...Un can be stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery consumption detecting device used in a device having a plurality of input / output units driven by batteries. Here, as the input / output unit, an input unit such as a keyboard, a panel switch, a bar code scanner, an optical character reader (OCR), an image scanner, a handwriting character input device, a voice input device, a magnetic card input device, or a display. There are output units such as a device, a printing device, and a voice output device, various communication devices using electricity, light, and wireless such as a facsimile device, and a drive device for a storage medium such as a memory card, a floppy disk, and an optical disk.

[0002]

2. Description of the Related Art A portable information input / output device driven by a battery is being integrated with various input / output units and miniaturized in accordance with higher performance. The current consumption of the input / output unit is desired to be kept as low as possible in order to reduce the size of the battery and thus the size of the entire device. However, in reality, there are units with various functions, and their current consumptions are inconsistent. For example, in the case of a bar code scanner, a pen type using an LED light source consumes about 10 mA, but a laser scanner using a helium neon laser reaches 1 A. In addition, the current consumption varies greatly depending on the usage conditions of various input / output units and the combination when a plurality of units are used.

On the other hand, since the voltage of a battery drops as it is used, it is usual to check the battery voltage during operation as a measure of whether or not the battery has run down. When the battery voltage drops below a certain voltage (called the cut-off voltage), the usable units are limited (Japanese Patent Laid-Open No. 3-2268).
No. 14, gazette), it is supposed to be charged or replaced.

[0004]

However, as the current consumption increases, the voltage drop of the battery increases according to the internal resistance of the battery during operation. That is, the voltage drop becomes more remarkable as the current consumption increases as the smaller battery having a larger internal resistance is used. Therefore, when the final voltage is set to a single value, if the final voltage is adjusted when the current consumption is small, it will fall below the final voltage when many I / O units happen to be driven simultaneously and a large current consumption flows. As a result, it is determined that the life of the battery has ended before the battery is sufficiently discharged.

In this case, not only the usability of the device is deteriorated, but also in the case of a Ni-Cd battery or the like, a memory effect (repeated shallow charging / discharging leading to a decrease in battery capacity) occurs. On the contrary, if the final voltage is adjusted when the current consumption is large, the battery is over-discharged when the current consumption is small, which may shorten the life of the battery or cause liquid leakage.

Therefore, an object of the present invention is to solve the above-mentioned technical problems and to provide a battery consumption detecting device capable of maintaining the life of the battery by surely detecting the consumption of the battery.

[0007]

[Means and Actions for Solving the Problems]

(1) A battery consumption detecting device according to claim 1 for achieving the above object, means for detecting a voltage E of a battery, and a battery end voltage V1, V2 corresponding to each of the input / output units.
.., Vn, and means for setting the optimum final voltage V according to the input / output unit being driven, based on the current switching state of the switching means, and the detected battery voltage E
However, when it is detected that the voltage is lower than the optimum final voltage V, the means for stopping the power supply to the input / output unit is provided.

According to the above construction, the final voltage V is set according to the combination of the input / output units currently used. Therefore, by comparing the final voltage V with the voltage E of the battery, The condition can be evaluated accurately with the same criteria. FIG. 1 is a diagram showing a specific configuration of a battery consumption detecting device used in a device having a plurality of input / output units according to the present invention.

A plurality of input / output units U1, U2, ...
Un is switched and driven by the changeover switch 1. The changeover operation of the changeover switch 1 is controlled by a control unit (not shown) that operates the entire apparatus, and the changeover state is input to the final voltage setting unit 2. The final voltage setting unit 2 stores the relationship between the switching state and the final voltage V, or can derive the relationship between the switching state and the final voltage V by calculation.

When the input / output unit is operating or before it is operating, the final voltage setting section 2 can determine the present optimum final voltage V based on the input switching state of the changeover switch 1. The final voltage V is input to the comparison unit 3, and the voltage E of the battery 4 is input to the comparison unit 3 for comparison. The comparison unit 3 outputs an active signal only when E <V. This signal is the power cutoff unit 5
, And is used to stop all or some of the input / output units U1, U2, ..., Un.

Therefore, the input / output units U1, U2
..., regardless of which combination of Un is operating
It is possible to accurately evaluate the degree of consumption of the battery 4 based on the same standard and stop the supply of power to the input / output units U1, U2, ..., Un. (2) The battery consumption detecting device according to claim 2 has a battery voltage E
To detect an electric current value I flowing from the battery to the input / output unit, a means for setting an optimum end voltage V according to the detected current value I, and a detected battery voltage E. And a means for stopping the supply of power to the input / output unit when it is detected that the voltage is lower than the optimum final voltage V.

According to this structure, the final voltage V is calculated according to the current value I actually flowing from the battery, so that the final voltage V is compared with the voltage E of the battery to determine the consumption current. Regardless of, it is possible to accurately evaluate the state of the battery with the same standard. FIG. 2 is a diagram showing a specific configuration of a battery consumption detecting device used in a device having a plurality of input / output units according to the present invention.

A current detector 6 for detecting the power supply current I supplied to the plurality of input / output units is provided.
The current value I detected by is input to the final voltage setting unit 2. The final voltage setting unit 2 stores the relationship between the current value I and the final voltage V, or can derive the relationship between the current value I and the final voltage V by calculation.

When the device is operating, the final voltage setting unit 2 sets the current optimum final voltage V based on the current value I detected by the current detection unit 6. The final voltage V is input to the comparison unit 3 as in the invention according to claim 1, and the voltage E of the battery 4 is also input to the comparison unit 3. The comparison unit 3 outputs an active signal only when E <V. This signal is input to the power cutoff unit 5 and used to stop the input / output units U1, U2, ..., Un.

According to the second aspect of the invention, the final voltage V is not determined based on the switching state of the plurality of input / output units U1, U2, ...
1, U2, ..., Un is different in that the final voltage V is determined based on the total current value I flowing through Un. Therefore, a means for detecting the switching state is unnecessary. (3) The battery consumption detecting device according to claim 3 further comprises means for instructing the battery consumption to the outside when detecting that the battery voltage E becomes lower than the final voltage V. According to this, it is possible to promptly notify the outside of the consumption of the battery to the outside so as to prompt the replacement or charging of the battery. (4) The battery consumption detecting device according to claim 4 further comprises means for switching to a backup battery when detecting that the battery voltage E becomes lower than the final voltage V. By switching to the backup battery,
It becomes possible to continue the operation of each unit in the entire apparatus.

[0016]

Embodiments will be described in detail below with reference to the accompanying drawings showing embodiments. FIG. 3 shows a configuration in which the functions of the changeover switch, the changeover detection unit, and the final voltage setting unit of the present invention are integrally realized by a CPU that controls the operation of the entire apparatus. C
PU is a plurality of input / output units U1, U2, ...
The drive switching state is always grasped, the relation between the switching state and the final voltage V is obtained from the table stored in the ROM, the optimum final voltage V is obtained by calculation, and this final voltage V is set as the voltage of the battery E. In comparison, when V <E, it has a function of stopping the input / output units U1, U2, ..., Un. Therefore, in the first embodiment, the CPU is
The function of each element can be realized in a unified manner. In addition, a backup battery is provided, and when battery exhaustion is detected, the switch automatically switches to the backup battery.

In the table describing the relationship between the switching state and the final voltage V, the input / output units U1, U2, ...
., Un when each operates independently Δ
V1, ΔV2, ..., ΔVn are stored. The optimum final voltage V is obtained as follows. That is,
Input / output units U1, U2, ...
If i = 0 (when not operating) or ai = 1 (when operating),
The final voltage V when any or all of the input / output units U1, U2, ..., Un are operating is V = V0- (a1 .DELTA.V1 + a2.DELTA.V2 + ...
n). However, V0 is the final voltage when no unit is operating.

The control operation performed by the CPU is as shown in the flowchart of FIG. First, the user selects an input / output unit to be used by key input (step S).
1). Then, the values of a1, a2, ..., An are determined accordingly (step S2). Next, the values ΔV1, ΔV2, ..., ΔVn are read by referring to the table (step S3). Then, the final voltage V is calculated according to the above formula (step S4) and stored in the RAM (step S4).
5). When the input / output unit is driven (step S6),
The voltage E of the battery input from the A / D converter is compared (step S7). If E <V, the process proceeds to step S8 to check the number n of operating input / output units. If n = 1, the process proceeds to step S9, the operation of the device is stopped, the battery exhaustion is displayed, and the battery is switched to the backup battery. At this time, the CPU may be provided with, for example, a buzzer so that when the battery consumption is detected, the sound is notified to the outside. If n> 1, then
In step S10, it is determined which of the input / output units should be stopped. Which I / O unit should be stopped
It is determined on the condition that the final voltage V calculated for the remaining I / O units after the stop exceeds the voltage E of the battery. If it is necessary to stop all the input / output units, the process proceeds to step S9. If not, the process returns to step S2, and the procedure after step S2 is repeated for the remaining input / output units after the stop.

[0019]

As described above, according to the battery consumption detecting device of the first aspect, since the final voltage V is set according to the combination of the input / output units currently used, the battery voltage E is By comparing with the cut-off voltage V, it is possible to accurately evaluate the consumption state of the battery with the same reference regardless of the amount of current consumption, and to stop the power supply to the input / output unit currently used at the time of consumption. it can.

According to the battery consumption detecting device of the second aspect, the final voltage V is determined according to the current value I actually flowing from the battery.
Therefore, by comparing the final voltage V with the voltage E of the battery, it is possible to accurately evaluate the exhaustion state of the battery with the same reference regardless of the amount of consumed current. It is possible to stop the power supply to the input / output unit that is operating.

According to the battery consumption detecting device of the third aspect, it is possible to promptly notify the outside of the consumption of the battery to the outside so as to prompt the replacement or charging of the battery. According to the battery consumption detecting device of the fourth aspect, by switching to the backup battery, the operation of each part in the entire device can be continued.

[Brief description of drawings]

FIG. 1 is a diagram showing a specific configuration of a battery consumption detecting device used in a device having a plurality of input / output units according to the first aspect of the invention.

FIG. 2 is a diagram showing a specific configuration of a battery consumption detecting device used in a device having a plurality of input / output units according to a second aspect of the invention.

FIG. 3 is a block diagram showing a configuration in which the functions of a changeover switch, a changeover detection unit, and a final voltage setting unit are integrally realized by a CPU that controls the operation of the entire apparatus.

FIG. 4 is a flowchart showing a control procedure performed by a CPU.

[Explanation of symbols]

 1 Changeover switch 2 Final voltage setting part 3 Comparison part 4 Battery 5 Power cut-off part 6 Current detection part U1, U2, ..., Un Multiple input / output units

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G06F 1/30 7165-5B G06F 1/00 341 Q

Claims (4)

[Claims] 1. A battery consumption detecting device used in a device having a plurality of input / output units driven by batteries and a switching means for operating one or a plurality of the plurality of input / output units in combination. , Vn corresponding to the input / output unit, and the current switching state of the switching means, the input / output being driven. Means for setting an optimum final voltage V according to the unit, and when detecting that the detected battery voltage E is lower than the optimum final voltage V, supply of power to the input / output unit is stopped. And a means for detecting battery consumption. 2. A battery consumption detecting device used in a device having a plurality of input / output units driven by batteries and a switching means for operating one or a plurality of the plurality of input / output units in combination. A means for detecting the voltage E of the battery, a means for detecting a current value I flowing from the battery to the input / output unit, a means for setting an optimum end voltage V according to the detected current value I, And a means for stopping the supply of power to the input / output unit when it is detected that the voltage E of the battery is lower than the optimum final voltage V. 3. The battery consumption detection according to claim 1, further comprising means for instructing battery consumption to the outside when detecting that the battery voltage E becomes lower than the power supply voltage V. apparatus. 4. The battery consumption detecting device according to claim 1, further comprising means for switching to a backup battery when detecting that the battery voltage E becomes lower than the power supply voltage V. .