JPS5845670B2 - Battery tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a battery tester, particularly a battery tester that determines the remaining weight or state of charge of a battery, as well as its quality.
Regarding testers.

Conventionally, various electric vehicles that use batteries as a power source,
For forklifts and other equipment, it is difficult to determine the remaining weight, state of charge, and quality of the battery, and the terminal voltage is usually measured using an ordinary voltmeter. Since the indication fluctuates widely, there are disadvantages such as the measurement is not performed automatically, the indication is instantaneous and the remaining battery capacity cannot be indicated continuously, and overall thermal reliability cannot be obtained. There wasn't.

The present invention provides a portable battery tester, the purpose of which is to instantaneously connect a low resistance with a heavy load compared to the battery capacity to one terminal of the battery at appropriate time intervals. To provide a battery tester that measures the instantaneous voltage of a battery and continuously confirms and instructs the state of charge with high reliability.

A feature of the present invention is to provide a device that can be assembled into a portable measuring instrument as a single unit, and can also have the form of a built-in panel meter in a battery-powered device. .

The operating principle of the present invention is to instantaneously connect a low resistance with a heavy load compared to the battery capacity at appropriate time intervals (approximately 30 to 60 seconds) between one terminal of the battery. The instantaneous voltage is instructed to be measured by a specific electronic voltage measuring circuit described below, and the remaining charge of the battery is confirmed by measuring the voltage at one terminal of the battery under a constant load condition.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of the present invention, in which 1 is a battery to be measured, 2 is a cycle determining circuit, 3 is a monomulti circuit, 4 is a relay circuit, and 5 is an instantaneous voltage detection section. ,
Reference numeral 6 indicates an instruction circuit.

FIG. 2 shows an example of the circuit configuration of the block diagram in FIG. 1, and in the same figure, each block surrounded by a dashed line corresponds to the block in FIG. 1.

That is, a, b, c, d, e, and f in FIG. 2 correspond to blocks 1, 2, 3, 4, 5, and 6 in FIG. 1, respectively.

In FIG. 2, a is a battery to be measured, and b is a cycle determining circuit, which is an intermittent oscillator using a UJT (unijunction transistor) and has a cycle of about 30 seconds to 60 seconds.

C in FIG. 2 is a monomulti circuit, and the conduction time in each period is about 80 milliseconds.

d is a relay circuit, and C operates relay d1 for the time obtained by subtracting the relay activation delay time from the conduction time (for example, if the activation delay time is 30 milliseconds, 80-30 = 50 milliJ seconds), and the relay contact e1 is closed and the battery to be measured a is connected to the load e2.

Reference character e in the figure is an instantaneous voltage detection section shown in block 5 of FIG. 1, and the instantaneous voltage generated at the low resistance terminal e2 is indicated by a meter f5 as a steady voltage in an indicating circuit f.

In the indicator circuit f, f2 is an instantaneous voltage holding capacitor, which is added to a series circuit of f2 and a constant voltage diode f3 via a diode f1, and f2 has the characteristic voltage of the constant voltage diode f3 from the instantaneous voltage of the battery a. The voltage obtained by subtracting the voltage is held charged, and there is no backflow discharge to the low resistance e2 side due to the action of the diode f1.

f4 is a Darlington circuit, which constitutes an impedance conversion circuit for displaying the charging voltage on the meter f5, and keeps the charging of the capacitor f2 substantially constant during the relay operating period determined by the period determining circuit. This is to convert the impedance of the voltmeter (meter) f5 to a sufficiently high impedance so that the impedance is maintained.

Therefore, it goes without saying that an element that provides a sufficiently high input impedance, such as an FET, would be even better.

In this way, the instantaneous battery voltage under load is displayed on the voltmeter f5 as a continuous steady state voltage.

Further, the zero point of this voltage indicator corresponds to the voltage of the constant voltage diode f3.

Therefore, for example, in the case of a 12-inch battery, if the voltage of the voltage f3 of the constant voltage diode is IOV, the voltage from 10-inch to 12V will be expanded to the full scale of the meter, so the voltage change of the battery during the discharging process will be indicated. Can be read accurately.

In the embodiments shown in FIGS. 1 and 2, a relay circuit, which is a mechanical switch, is used to facilitate understanding of the invention.
It is possible to replace the mechanical switch with an electronic switch to ensure high reliability in the current flow.

As explained above, the present invention measures the instantaneous voltage between the terminals by activating a mechanical or electronic switch that automatically switches on and off a constant low resistance load on the battery at regular intervals for a very short period of time. It provides a battery tester that continuously confirms and instructs a certain state of charge, and as mentioned above, it is extremely effective in practical use because it can indicate the remaining weight of the battery as a portable or built-in type. .

[Brief explanation of the drawing]

The figure shows the configuration of one embodiment of the present invention.
The figure is a block diagram showing the circuit configuration of the present invention, and FIG.
2 shows a circuit diagram of the block diagram of FIG. 1; FIG.

Claims (1)

[Claims] 1. For the battery under test, a cycle determining circuit consisting of an intermittent oscillator, a mono-multi circuit that determines the conduction time according to each cycle determined by the circuit, and a mechanical or electronic device whose operating time is determined by the circuit. an instantaneous voltage detection section that connects a mechanical or electronic switch and intermittently connects a certain low resistance heavy load to the battery according to the operation of the mechanical or electronic switch, and detects the instantaneous voltage generated at the low resistance terminal of the detection section. A battery tester characterized in that it is equipped with an indicator circuit that indicates a steady voltage, and displays continuous changes in the amount of electricity remaining in a battery during discharging.