JPH069552Y2 - Sealed lead acid battery charger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to an improvement of a sealed lead-acid battery charger.

2. Description of the Related Art Conventionally, there is a charging method for a sealed lead-acid battery (hereinafter, referred to as "over-discharge left-over battery") after being left over-discharged as a problem of a sealed lead-acid battery charger.

In particular, as the sealed lead-acid battery charger, a charger in which charging with a small current (hereinafter referred to as “trickle charging”) is started after the end-of-charge voltage is detected is often used. When an over-discharged battery is charged by this battery charger, the internal resistance of the battery is high, so that the charging voltage reaches the end-of-charging voltage immediately after the start of charging, and there is a drawback that the trickle charging is rarely performed.

As one of the methods to solve this drawback, Japanese Patent Application No.
As disclosed in the specification of No. 61-16196, there is a method in which after charging is started, a current is supplied in a direction opposite to the normal direction to perform charging (hereinafter referred to as “reverse charging”), and then normal charging is performed.

Problems to be Solved by the Invention One of the means for implementing the above-described charging is a method of returning to normal charging after performing reverse charging for a certain period of time. . This method has a problem that the charging time becomes long when the reverse charging is performed, and the time until completion of charging cannot be estimated.

Means for Solving the Problems The present invention is characterized by solving the above-mentioned problems and including means for displaying the state of reverse charging during reverse charging.

Function Since the present invention has the above-mentioned characteristics and displays the state of reverse charging, it is possible to indicate that the charging time becomes long when the battery goes into reverse charging.

Embodiment An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the normal charging state and the reverse charging state by adding a reverse charging function to the charger which is like trickle charging when the set voltage is reached by charging the battery of the present invention with a quasi-constant current. It is a thing. That is, the output of the transformer 2, which receives the AC power supply 1 as an input, is rectified through the diode 3 and the diode 4, passes through the transistor 6, passes through the backflow prevention diode 13, and flows into the sealed lead-acid battery 15 as a charge stream. The transistor 6 controls the charging double current, switches between the charging double current and the trickle charging current, and the resistor 5 controls the trickle charging current. The control unit 12 is used as an input.

The control unit 12 detects the voltage at the end of charge at the time of normal charging by the voltage detection unit 18, turns off the output to the transistor 11 and controls the transistor 6 for trickle charging, and when an over-discharged battery is connected. Since the internal resistance of the battery is high and the charging voltage becomes higher than usual, the voltage is detected by the voltage detection unit 17 and output to the relay 16 and to the transistor 9 and the diode 8
Is displayed and held for a certain period of time, and then the light emitting diode 10 is turned on to perform normal charging. The light emitting diode 10 is turned off when trickle charging is started.

Fig. 2 shows the charging characteristics of the battery charger of the present invention. (A) is for charging an over-discharged battery and (b) is for charging a normal sealed lead-acid battery. 4V-
4AH, internal resistance is 300Ω, 15mΩ respectively, and overcharge left battery is 10 ° -0 ′ before trickle charge, whereas normal battery is 3 ° -40 ′, the former one Is much longer than the latter.

In this way, the reverse charging state of the over-discharged battery, which has a long charging time before trickle charging, can be displayed by the light emitting diode.

In FIG. 1, 7 is a resistor and 14 is a contact of the relay 16. Further, in FIG. 2, V indicates a charging voltage and I indicates a charging current.

Effect of the Invention As described above, the present invention is applicable to charging an over-discharged battery,
Since the state of reverse charging is displayed, it can indicate that a long charging time is required, which is of great practical value.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of the charger of the present invention, FIG. 2 is a charging characteristic of the charger of the present invention, (a) is a charging characteristic curve diagram when an over-discharged battery is charged, and (b) is normal. FIG. 4 is a charging characteristic curve diagram when a different sealed lead-acid battery is charged. 6: Transistor, 8: Light emitting diode, 9: Transistor, 12: Control unit, 13: Backflow prevention diode, 15: Battery, 16: Relay, 17: Reverse charging voltage detection unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Komaki 2-1-1, Nishishinjuku, Shinjuku-ku, Tokyo Shin-Kuroto Electric Co., Ltd. Inspector Akira Suzuki

Claims (1)

[Scope of utility model registration request] 1. A sealed lead-acid battery charger that performs normal charging by applying a voltage in the opposite direction to the normal voltage until the battery voltage becomes a negative state, and A sealed lead acid battery charger comprising means for displaying a state of being added.