JPS59211972A - Cell remainder recognition circuit - Google Patents

Abstract

PURPOSE:To minimize the dispersion error for each cell by individually discharging from a cell to two discharge loads, large and small, and recognizing and judging the cell remainder based on the difference between voltage drops of the cell during discharge respectively. CONSTITUTION:Two pulse discharge circuits D1, D2 corresponding to two discharge loads, large and small, are provided, a pulse discharge with a small current is performed through the pulse discharge circuit D1, a pulse discharge with a large current is performed through the pulse discharge circuit D2, and these pulse discharge circuits D1, D2 are controlled by monostable multivibrators MV1, MV2 respectively. Peak hold circuits PH1, PH2 are controlled by outputs of monostable multivibrators MV1, MV2 respectively and operated at the same timing as that of the first and the second pulse discharge circuits D1, D2, and the peak value of the terminal voltage of a cell B is detected to generate an output. A subtracting circuit G detects the difference between outputs PH1, PH2 to generate an output, the output of this subtracting circuit G is amplified by an amplifying circuit Ap and fed into a relation comparing circuit C, and the remainder of the cell B is detected and recognized and displayed on a display unit H.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a battery-operated device such as a rechargeable electric shaver that has a residual amount of battery in order to prevent the device from stopping during use due to a dead battery. [Background technology] Conventionally, when recognizing and determining the remaining battery level, a predetermined discharging load from the battery is used to display the remaining battery level. The battery was then discharged, and the remaining battery power could be determined based on the state of the battery's voltage drop at this time.

However, in such a conventional example, although it is possible to recognize and determine the remaining capacity of each individual battery, there is a very large variation in the number of batteries, and the process of correcting this variation becomes complicated and troublesome. There was a problem.

[Purpose of Hamoe]

□The present invention is a battery remaining power recognition circuit that minimizes the variation error when recognizing and determining the remaining battery power, and allows accurate recognition and determination of the remaining power while being used without any adjustment. The purpose is to provide the following.

[Disclosure of the invention]

The present invention recognizes and determines the remaining capacity of battery B by detecting the voltage drop of battery B during pulse discharge.
Two types of discharge loads, large and small, are provided, and the difference in voltage drop during pulse discharge to these discharge loads is detected, and the relationship between the difference in voltage drop and the preset remaining battery capacity is calculated as described above. The remaining capacity of battery B is recognized and determined by comparing the detected differences.

(Embodiment 1) FIG. 1 shows a first embodiment of the present invention, in which two pulse discharge circuits D1 and D2 corresponding to two types of discharge loads, large and small, are provided, and the pulse discharge circuit D+ generates small current pulses. The discharge is performed by pulse discharge of a large current by the pulse discharge circuit D2, and these pulse discharge circuits Dt,
Dzld each monostable multipipe one MVI, MV2
controlled by In the figure, PH2 is a peak hold circuit, G is a subtraction circuit, AP is an amplification circuit, C is a relational comparison circuit, and H is a display.

Thus, in the circuit of the embodiment shown in Fig. 1, the switch SW
When the oscillator is turned on, a trigger signal as shown in Fig. 2 (a) is generated, and the monostable multivibrator MVI operates, and as shown in Fig. 2 (a).
b) Generates a pulse like the one shown below. The first pulse discharge circuit D1 is turned on at the rising edge of the pulse shown in FIG.
Until the first pulse discharge circuit D+ is turned off at the falling edge of the pulse shown in (b) of the same figure, a small current pulse discharge is performed as shown in (d) of the same figure. At the same time as the vibrator MVI falls (c)
The second monostable multivibrator MV2 rises as shown in the figure, and at the same time as this rise, the second pulse discharge circuit D2 is turned on until it falls, and a large current pulse discharge occurs as shown in (d) of the same figure. It is done. On the other hand, the peak hold circuits PHI and PH2 are controlled by the monostable multivibrator MVI and MV2 outputs, respectively.
, second pulse discharge circuit D1. It operates at the same timing as II, and if the terminal voltage of battery B changes as shown in figure (e) due to the discharge current flowing as shown in figure (d), the peak hold circuit PHI
.

PH2 detects the peak value in each operating time period and produces outputs as shown in (f) and (g) of the figure.

Subtraction circuit G, for example, resistors R, R, R, R and operational amplifier O
It is configured as shown in Figure 5 with P and detects and outputs the difference between the outputs of both peak hold circuits PHI and PH2, and the output of this subtraction circuit G is amplified by an amplifier circuit.
It is input to a relational comparison circuit C. The relationship between the remaining amount of battery B and the difference detected by the subtraction circuit G is as shown in FIG. Detects and recognizes the remaining amount of battery B,
This is displayed on the display H.

(Embodiment 2) FIGS. 5 to 7 show a second embodiment of the present invention, in which a divider W is added to the first embodiment described above, and one discharge Discharge voltage drop due to discharge to load,
The difference rate is calculated as the ratio of the difference in discharge voltage drop due to discharge to both discharge loads, and the divider W is divided into five amplifiers LA1 to LA3 and the The circuit is composed of subtracters G1 and K, which have the same configuration as the circuit in Figure 5, and the relationship between the output of the divider W, that is, the above-mentioned difference rate, and the remaining battery capacity is as shown in Figure 7, for example. The remaining capacity of battery B is detected and recognized by relational comparison circuit C based on O (Third Embodiment) Figures 8 and 9 show a fifth embodiment of the present invention. A third monostable multivibrator M■ controlled by the output of MV2 is provided, and this third monostable multivibrator MV3 turns on the pulse discharge circuit D2 of the rod 2 to generate the first and second pulse discharges. The on-starts of the circuits DI and D2 are temporally separated from each other, and the difference in voltage drop due to the first and second pulse discharges is detected by a divider W as a ratio between the two. However, in this third embodiment, the first to fifth monostable multivibrators Mv1 to
The MV convex operates as shown in the figure (b) to (d), and the figure (e
), a pulse current flows from battery B. This causes a voltage drop in battery B as shown in (f) in the same figure, which is then held at the peak w! rPHI and PH2 are detected as shown in (g) and (h) of the same figure, respectively, and further the divider W
The output shown in (i) in the same figure is obtained by dividing the power of Ryokawa by . According to the output of this divider W, the relational comparison circuit C recognizes and determines the remaining battery level, and the display H shows the remaining battery power. It is to be displayed.

〔Effect of the invention〕

As described above, the present invention provides two types of discharge loads, large and small, discharges from the battery individually to these discharge loads, and recognizes and discriminates the remaining battery capacity from the difference in voltage drop of the battery during each discharge. Because of this, it is possible to minimize the variation error for each battery and more accurately display the remaining battery power, and there is no need to make adjustments to compensate for variations during manufacturing. This has the effect of greatly improving productivity.

[Brief explanation of drawings]

Figure 1 is a 1099 diagram of the first embodiment of the present invention, Figure 2 is a time chart of the same as the above, Figure 5 is a circuit diagram of the subtraction circuit of the same as the above, and Figure 4 is the remaining battery level and the output of the subtraction circuit of the same as the above. Fig. 5 is a 1099 diagram of the second embodiment of the present invention, Fig. 6 is a detailed diagram of the division circuit of the same as above, and Fig. 7 is a diagram of the remaining battery power and division of the same as above. FIG. 8 is a block diagram of the fifth embodiment of the present invention, FIG. 9 is a time cisode as described above, and B is a battery. Agent Patent Attorney Ishi 1) Chief 7 Figure 3 R Remaining 10% - 1% Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (3)

[Claims] (1) Two types of discharge loads, large and small, are provided, and the batteries are discharged individually to each discharge load, and the remaining battery capacity is determined and recognized from the difference in voltage drop in the batteries during each discharge. Features a battery level recognition circuit. (2) Find the difference rate as the north of the difference between the discharge voltage drop during discharge for either discharge load and the discharge voltage drop due to normal discharge for both discharge loads, and use this difference rate to determine and recognize the remaining battery capacity. 1. A battery remaining amount recognition circuit as set forth in claim 1, characterized in that the circuit is configured such that: (3) The remaining battery capacity recognition circuit as set forth in claim 11, wherein the battery discharges for two types of discharge loads, large and small, are performed temporally apart from each other.