JPS61191237A - Charger for storage battery - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a charger for storage batteries, and in particular to a so-called peak charger that controls the charging current when the charging voltage drops from the peak value of the charging voltage of the storage battery to be charged. , relates to improvements in pressure detection methods.

(Prior Art) A storage battery head system called the so-called peak voltage detection method has been proposed, which detects the peak point of the charging voltage that appears at the end of charging of a sealed storage battery based on the charging voltage that subsequently decreases, and controls the flow of charge to the storage battery. has been done. (For example, JP-A No. 5
(Publication No. 4-162140) (Problems to be Solved by the Invention) This device can rapidly charge a storage battery to be charged with a relatively large flow of charge quality, and can reliably detect the end of charging regardless of the temperature of the storage battery. However, if the temperature range is above a predetermined value, e.g. 50'C or more, or below a predetermined value, e.g. 0°C or less, the charging current may have various negative effects on the storage battery. give and its lifespan decreases.

(Means for Solving the Problems) The present invention eliminates any of the conventional drawbacks and includes a means for detecting the temperature of a storage battery or its surroundings, and charges the storage battery when the temperature becomes above or below a predetermined value. In addition to making it possible to control the current, when the temperature returns to a predetermined range, the delay circuit eliminates the influence of the existing peak value detection means, so that rapid charging can be reliably returned.

(Example) An example of the present invention will be described in detail based on the drawings.
il is a direct current power supply section, which includes, for example, a connection plug to a commercial alternating current, a transformer, a rectifier connected to the secondary side of the transformer, and the like. (2) is a constant current circuit section, which has a common collector.
It consists of two transistors (Ql, C2) and a diode (DI, D2) connected between the emitter and base of the transistors (Ql, C2). (3) is a storage battery to be charged, such as a sealed nickel-cadmium storage battery, which is connected in series to the constant current circuit section via a diode (D3), and is charged and current supplied to the constant current circuit section (2) by the DC power supply section +++. It is controlled at a constant rate and is made seven times M1. (4) is a peak voltage detection section, which includes a series circuit consisting of six resistors (R1, R2, R3) and a Zener diode (ZDl) connected in parallel with the storage battery to be charged (3);
Six OP amplifiers (IC1, IC2, IC3) whose output terminals are connected in sequence to non-inverting input terminals (-1-IK),
It consists of a peak bold capacitor (C1) connected to the output terminal of the first op amp (IC1), etc.
The sixth OP amplifier (IC3) is used as a comparator, and its inverting input terminal (-) is connected to the series circuit (A), and the non-inverting input terminal (+) of the first OP amplifier (rc'+) By detecting the potential difference with the point (port 1) that is directly read from the series circuit, and holding the potential at point (b) by the capacitor (C1), the voltage at point ) point voltage or capacitor (
An output signal is output from the output terminal of the third op amp (Ice) when the potential is lower than the potential held by the third op amp (Ice). (5) is a temperature detection section with two comparators (IC4,
It consists of an IC 5), a thermistor (TH), etc., and the thermistor (TH) is provided in contact with or in close proximity to the storage battery to be charged (3), and detects the temperature of the storage battery itself or its surroundings. Two comparators (IC4, IC5) are installed at the midpoint of the series circuit of the thermistor (TH) and the resistor (R4).
) are connected to the non-inverting input terminal [-1-1 and the inverting input terminal (-), and the other inverting input terminal (-) and d non-inverting input terminal are connected to a dividing resistor (R5 , R6, R7 and R8, R9, R10). And each funparator (IC4, I
The output terminal of C5) is shared, and an output signal is output from the output terminal according to the resistance value of the thermistor which changes depending on the temperature. (6) is a thyristor (TJ(YI)) in the control section.
The output terminal of the comparator (IC6) is connected to the base of the transistor (C2) of the constant current circuit section (2), and the thyristor (THYI) is connected to the base of the transistor (C2) of the constant current circuit section (2).
) is connected to the output terminal of the peak voltage detection section (4) via a diode (D4). Further, the output terminal of the temperature detection section (5) is connected to the inverting input terminal (-) of the comparator (IC6), and the output terminal and the peak voltage detection section (41) are connected to the inverting input terminal (-) of the comparator (IC6).
The output terminals of are connected via a diode (D5). (D6) is the inverting input terminal (
-) and the 7 nodes of the thyristor (TI (YI). (7) is an extended circuit consisting of a Zener diode (Zn2) and a capacitor (C2), and the peak lightning and voltage A Zener diode (Zn2) is connected in series with a capacitor (C2) between the output terminal of the detection section (4) and the gate of the thyristor (THYI) of the control section (6).
) are inserted in parallel. +81 is the timer circuit section, and the timer (MC14541B manufactured by Motorola)
), etc., and controls the charging time to control the peak voltage detection section (
4) is a safety timer to prevent overcharging in case of failure to operate, and its output terminal is connected to a diode (D
*+f control (6) thyristor (THYI)
), and the charging current is controlled by the timer output.

In the figure, (R11) to (R23) are resistances (D8) to (Dl
o) indicates a diode.

The charger configured in this way turns on the DC power supply section (1).
Then, the transistors (Ql) and (C2) become conductive and quickly charge the storage battery (3) to be charged. Meanwhile, the peak voltage detection section (4) constantly detects the charging voltage of the storage battery to be charged (3) through a series circuit of resistors (R1, R2, R3) and a wound Zener diode (ZDl) connected in parallel. When the storage battery to be charged (3) reaches its final stage of charging and the charging voltage has passed the peak point, the voltage at point (a) of the series circuit drops from the normal pressure at point (b) instantaneously earlier, so the third op. A detection signal is output from the amplifier (Ice), charges the capacitor (C2) of the delay circuit (7), and when it becomes higher than the Zener potential of the Zener diode (Zn2), it is applied to the gate of Thyrisk (THYI) of the control unit (6). Then, the thyrisk (THYI) becomes conductive, and due to the conduction, the electric potential to the inverting input terminal of the comparator (IC6) decreases, and an output signal is generated from the output terminal of the conoparator (IC6), and the constant current circuit section Since the base potential of the transistor Q2 in (2) becomes high, it becomes non-conductive and the charging current to the charged storage battery (3) starts from rapid charging!・Charging of the charged storage battery (3) is controlled safely by trickle charging through only run risk (Ql) and changes completely, so the input signal of the comparator (IC4 or IC5) is inverted and its output The output signal from the end is I (from the level L)
As the level signal changes, the input of the comparator (IC6) of the control section (6) is inverted, and an output signal is output from its output terminal, and as above, the transistor (C) of the constant current circuit section (2)
2) becomes non-conductive and rapid charging is controlled. At this time, as the charging current decreases, the peak voltage detection section (4)
operates and outputs an output signal, but the signal flows into the comparator (IC4 or IC5) via the diode (D5) and the THYI of the control section (6) is not conductive.

When the temperature returns to the predetermined value, the input signal of the comparator (IC4 or IC5) of the temperature detection section (5) returns to the original value, and therefore the input signal of the comparator (IC4 or IC5) of the control section (6) returns to the original value.
6) also returns to its original state and the transistor (C) of the steady flow circuit section (2)
2) becomes conductive and the charged storage battery (3) is quickly charged again. During this time, there is some time lag until the output signal of the peak voltage detection section (4) stops, but the delay circuit consisting of the Zener diode (Zn2) and the capacitor (C2)
7) prevents the thyristor (THYI) of the control unit (6) from becoming conductive (reliably returns to rapid charging. Then, when the rechargeable battery (3) to be charged reaches the end of charging, a beep occurs, detecting normal pressure, and the above-mentioned The charging current is controlled by the timer circuit section (8) once the set time of the timer elapses, regardless of the presence or absence of peak voltage detection.The temperature detection section (5) and the peak voltage When the detection signals from the detection section (4) are almost simultaneous and the detection signal from the temperature detection section (5) is slightly earlier and then a predetermined detection signal is output from the peak voltage detection section (4), the temperature returns to the predetermined value. When this happens, the detection signal from the peak normal pressure detector (4) does not stop, so the capacitor (C2) of the delay circuit (7) is charged as described above, and when the voltage reaches or exceeds the Zener potential of the Zener diode (Zn2), the charging current stops. controlled.

(Effects) As described above, according to the present invention, quick charging can be performed safely and reliably within a predetermined temperature range at all times, and even if the temperature returns to the predetermined range after deviating from the predetermined temperature range, rapid charging can be performed reliably without malfunction. It has the effect of being able to return to normal.

[Brief explanation of drawings]

The figure is a circuit diagram of one embodiment of the present invention. (11... DC power supply section, f21... Constant current circuit section, (3
)...Storage battery to be charged, (4)...Peak voltage detection section, (
5) Temperature detection section, (6) Control section, (7) Delay circuit, (8) Timer circuit section

Claims (1)

[Claims] a first detection means for detecting that the charging voltage of the storage battery to be charged has decreased from a peak value; a second detection means for detecting that the temperature of the storage battery to be charged or its surrounding temperature has become above or below a predetermined value; and a means for controlling the charging current by a detection signal from either of the first and second detection means, and a signal from the first detection means when the temperature returns to the predetermined value from above or below a predetermined value. A storage battery charger that releases control of charging current by delaying the current.