JPH04357467A - Battery consumption detection device - Google Patents

Abstract

PURPOSE:To prevent a battery from being used up totally by predicting a battery life of an equipment using the battery. CONSTITUTION:A title item is provided with an A/D conversion device 3 which measures a battery voltage and a microcomputer 4 which recorded a plurality of battery discharge curves at a memory region previously. By comparing a battery voltage change which is obtained by A/D conversion for a certain amount of time with a battery discharge curve which is recorded at the microcomputer 4, the battery life of a used equipment is predicted and the predicted data is displayed at a display circuit 6. The above configuration prevents a device to be controlled 5 from being stopped halfway due to total consumption of the battery.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery consumption detection device for equipment using batteries.

0002

BACKGROUND OF THE INVENTION In recent years, the number of outdoor devices has been increasing due to the improvement in the performance of batteries, and furthermore, it has become possible to perform complex control in combination with microcomputers (hereinafter abbreviated as microcomputers). However, a new problem has arisen in which devices malfunction due to microcomputer program runaway due to a drop in battery voltage, and various battery consumption detection devices have been devised to prevent these problems.

An example of the above-mentioned conventional battery consumption detection device will be described below with reference to the drawings.

FIG. 4 is a block diagram showing the configuration of a conventional battery consumption detection device. In FIG. 4, 1 is a battery, 2 is a constant voltage power supply, 4 is a microcomputer, 5 is a controlled device, 6 is a display circuit, 9 and 10 are data lines, 11 is a voltage detector, 1
2 is a microcomputer reset line.

The voltage V of the battery 1 is changed to V by the constant voltage power supply 2.
The voltage is stabilized to 2 and is supplied to the microcomputer 4. The microcomputer 4 controls a controlled device 5 (for example, motor control) and a display circuit 6 (for example, an LED) via data lines 9 and 10.

FIG. 2 shows a graph showing the process by which the battery 1 is consumed. The curve of the graph varies depending on the load current, and shows the voltage change over time when the load current is sequentially reduced from I1 to I4.

[0007] Using this graph, the operating state when the battery 1 in the conventional example is exhausted will be explained. The constant voltage power supply output V2 depends on the voltage of the battery 1 and is supplied to the microcomputer 4 when the voltage of the battery 1 decreases and becomes lower than V2. When the voltage of the battery 1 further decreases and reaches the operating limit voltage V1 of the microcomputer 4, the voltage detector 11 resets the microcomputer 4 via the microcomputer reset line 12, and the controlled device 5 and display due to program runaway are reset. Malfunction of the circuit 6 is prevented.

[0008]

[Problems to be Solved by the Invention] However, in the conventional battery consumption detection device as described above, the process of battery consumption is unknown, and when the battery 1 reaches the microcomputer operation limit voltage V1 while the device is in use, the microcomputer 4 is reset,
The controlled device 5 and the display circuit 6 stop mid-operation, causing the device to become unusable, or, in the case of a recording device, resulting in destruction of recorded data.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention has been made with the object of providing a battery consumption detection device that can predict battery consumption time and prevent equipment from stopping mid-operation.

0010

[Means for Solving the Problems] In order to solve the above problems, the battery consumption detection device of the present invention stores a battery discharge curve in the memory area of a microcomputer in advance, and compares the voltage change over time of the equipment used with the battery discharge curve. This is to estimate the remaining battery life of the device.

[0011]

[Operation] With the above-described structure, the present invention prevents the equipment in use from stopping mid-operation by predicting the battery consumption time, thereby providing an effective usage environment for the equipment and the battery.

0012

[Embodiments] Hereinafter, embodiments of the battery consumption detection device of the present invention will be described in detail with reference to FIGS. 1 to 3.

FIG. 1 is a block diagram showing the configuration of a battery consumption detection device according to a first embodiment of the present invention.

In FIG. 1, 1 is a battery, 2 is a constant voltage power supply, 3 is an A/D converter, 4 is a microcomputer, 5 is a controlled device (eg, motor control), and 6 is a display circuit (eg, LED).
, 7 is an A/D conversion input line, 8 is an A/D conversion data line, and 9 and 10 are data lines.

The operation of the battery consumption detection device constructed as described above will be explained below.

First, let us consider a state in which the capacity of the battery 1 is sufficiently secured. The voltage V of the battery 1 is stabilized to a voltage V2 by a constant voltage power supply 2 and supplied to the A/D converter 3 and the microcomputer 4.

The A/D converter 3 converts the voltage V of the battery 1 into A
The battery voltage data is constantly measured via the A/D conversion input line 7, and the battery voltage data is transferred to the microcomputer 4 via the A/D conversion data line 8. The microcomputer 4 controls the controlled device 5 and the display circuit 6 through data lines 9 and 10, and these operations are the same as in the conventional example.

Here, the operation will be explained with reference to the load current versus battery discharge curve shown in FIG. 2 in a state where the capacity of the battery 1 is reduced.

For example, if the circuit current of the present invention is I shown in FIG.
Assume that 1. Furthermore, if the voltage of the battery 1 at the present moment is a, the time point b when it reaches the microcomputer operating limit voltage V1
The microcomputer 4 operates without any problems during the time period TE.

The microcomputer 4 calculates the amount of change in battery voltage over a certain period of time from the battery voltage data obtained by the A/D converter 3, and at the same time calculates the most Similar data is calculated and the display circuit 6 displays the time from the current voltage to the microcomputer operating limit voltage V1.

FIG. 3 is a flowchart showing the operation of the microcomputer 4. In step 1, the A/D conversion data D
1 is read and stored in the memory (random access memory, hereinafter abbreviated as RAM) of the microcomputer 4 in step 2. Step 3 is a timer for a fixed time T, and steps 4 and 5 store the A/D conversion data D2 of the battery 1 in the RAM of the microcomputer 4 again. In step 6, the microcomputer 4 compares these two data, and in step 7, the microcomputer 4 compares the data for a certain period of time T.
Calculate the amount of voltage change in . In step 8, the microcontroller memory (read-only memory)
It is abbreviated as OM. ) A comparison is made with the battery discharge curve previously recorded in the table, and in step 9 the most similar discharge curve is retrieved from the memory table. In step 10, the time required to reach the operating limit voltage V1 of the microcomputer 4 is calculated, and in step 11, it is displayed on the display circuit 6. This corresponds to the time display of TE in FIG.

Step 12 is a judgment process, and if the voltage of the battery 1 is sufficiently secured, the process returns to step 1 and the above-described operation is repeated. Further, when the voltage of the battery 1 decreases and reaches around the operating limit voltage V1 of the microcomputer, a warning and a reset means are used to prevent the microcomputer's program from running out of control.

As described above, according to this embodiment, the battery discharge curve is stored in advance in the ROM table of the microcomputer 4, and the battery discharge curve is determined from the amount of voltage change per hour of the equipment used. Since the time required to reach the operating limit voltage V1 is calculated and displayed, it is possible to prevent the device from being stopped mid-use due to battery exhaustion.

[0024] Note that the circuit current is not limited to only I1 but is constantly changing, and even if it changes up to I4, by calculating the interpolated value from the ROM table of the microcomputer 4, it is easy to estimate the usable time of the device. It is possible to do so.

[0025]

As described above, the present invention constantly monitors the battery voltage using an A/D converter, and also performs calculations and comparisons with the battery discharge curve recorded in advance in the memory table of the microcomputer. Excellent battery depletion detection that displays the remaining battery usage time, allowing the user to continue using the device without knowing the battery life, preventing the device from stopping mid-operation or causing problems due to the microcontroller's program running out of control. equipment can be provided.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a battery consumption detection device in an embodiment of the present invention.

[Figure 2] Battery load current vs. battery discharge curve

FIG. 3 is a flowchart showing the control procedure of the embodiment of the present invention.

[Figure 4] Block diagram showing the configuration of a conventional battery consumption detection device

[Explanation of symbols]

1 Battery 2 Constant voltage power supply 3 A/D conversion device 4 Microcomputer 5 Controlled device 6 Display circuit 7 A/D conversion input line 8 A/D conversion data line 9 Data line 10 Data line

Claims (3)

[Claims] 1. A control section having means for recording a plurality of battery discharge curves in a memory area, and a measurement section for measuring battery voltage of a device to be used, wherein the control section has a means for recording a plurality of battery discharge curves in a memory area; A battery consumption detection device, characterized in that the change is compared with a specific discharge curve among the plurality of discharge curves, and a time required for the battery voltage to reach an operating limit voltage of the control unit is calculated. 2. The battery consumption detection device according to claim 1, further comprising a display section provided after the control section for displaying the time until the battery voltage reaches the operating limit voltage of the control section. 3. The battery consumption device according to claim 1, wherein the specific discharge curve is determined based on a load current of a device using the battery.