JPH08138760A - Charging device for battery - Google Patents

Abstract

PURPOSE: To suppress the deterioration of a battery with a low cost and maintain its durability highly by providing a cooling means sending cool air to the battery in the closing of charging when the battery of an electrically driven cart is charged. CONSTITUTION: When a battery 2 mounted on an electrically driven cart is charged by a charger 1, a voltage between the terminals of the battery 2 is detected by a voltage detection means 4. When the voltage between the terminals of the battery 2 is detected to be about 90% or more of the voltage between the terminals at a full charge time on proceeding of charging, a timer driven circuit 7 switches a relay 8 to an on state so as to hold the on state for a predetermined time. Thereby, a cooling fan 9 is driven for the predetermined time so as to blow cooling air to the battery 2 heated up to a high temperature to prevent the deterioration of the battery 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery charging device mounted on, for example, an electric cart.

[0002]

2. Description of the Related Art Conventionally, in a battery charger of this type, if the battery during charging becomes unduly high in temperature, deterioration of the charging ability is accelerated, so that the battery temperature at the time of charging must be higher than the preset value. It is known that a cooling fan for cooling a battery is driven by an AC power supply for charging while the detection is made by a thermoswitch and the detection is made.

[0003]

However, in the above-mentioned conventional structure, since there is a difference in detecting the battery temperature depending on the installation location of the thermoswitch, the installation location of the thermoswitch for appropriately driving the cooling fan is required. There is a problem in that it is necessary to carry out a test or the like every time a design change or the like because it is necessary to consider appropriately setting it in the design. In addition, since an installation tool for installing the thermoswitch is required as a separate component, the cost is increased. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a battery charging device that is inexpensive and can reliably charge a battery while cooling it.

[0004]

In order to achieve the above object, a battery charging device according to the present invention includes a timer that operates for a predetermined time at the end of battery charging by a charger, and a cooling air flow for the battery. And cooling air blowing means for blowing air, and driving means for driving the cooling air blowing means by a charging power source while the timer is operating. The operation and effect of this characteristic configuration are as follows.

[0005]

That is, since the temperature of the battery becomes high during charging mainly at the end of charging, the end of charging is detected by observing the voltage across the terminals of the battery during charging, Cooling air is blown to the battery by the cooling air blowing means only for a predetermined time before the charging is completed.

[0006]

As described above, the cooling air blower is reliably driven by the charging power source based on the end of the charging at which the battery is most likely to be unduly hot and at the end of the charging. In addition, since it is not necessary to provide a thermoswitch or the like for detecting the battery temperature, the deterioration of the battery can be suppressed at a low cost, so that the durability of the battery can be maintained high.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows a small electric cart. This electric cart is mounted on a vehicle body frame 14 supported by a single wheel type front wheel 11 steered by a steering wheel H and a pair of left and right rear wheels 13, 13 driven by an electric motor 12.
The control seat 15, the batteries 2 and 2, the control device 16 and the like are installed and configured. A pair of left and right batteries 2 and 2 are provided, and a charger 1 is arranged in the space between the batteries 2 and 2 and
A cooling fan 9 is provided as cooling air blowing means for blowing cooling air to cool each of the above.

FIG. 1 shows a circuit of a charger 1 used for a battery 2 or the like mounted on an electric cart. This charger 1 charges a battery 2 using a commercial AC power supply as a charging power supply, and has a voltage conversion means 3 for converting the voltage of the commercial AC power supply into a voltage suitable for charging and a terminal of the battery 2. Voltage detecting means 4 for detecting an inter-voltage, voltage / current adjusting means 5 for appropriately adjusting the amount of current supplied to the battery 2 and a voltage value based on the detection result of the voltage detecting means 4 during charging, and a switch for starting charging. 6, and a timer drive circuit 7 as a timer that starts operating when the voltage between terminals of the battery 2 detected by the voltage detection means 4 reaches a predetermined voltage value lower than that at full charge (for example, 90% of full charge). , And a relay 8 as a drive unit that is operated by the timer drive circuit 7. Then, as shown in FIG. 1, the drive motor of the cooling fan 9 as the cooling air supply means is connected to the commercial AC power source through the normally open contact circuit 10 which is driven to be closed by the relay 8.

With the above configuration, when charging the battery 2, when the terminal voltage of the battery 2 is lower than 90% of the preset terminal voltage value when the battery 2 is fully charged, the timer drive circuit 7 Keeps the relay 8 in the off state, the charging progresses, and when it is detected that the terminal voltage of the battery 2 is 90% or more of the terminal voltage value when the battery 2 is fully charged,
The timer drive circuit 7 switches the relay 8 to the ON state and outputs a signal for holding the ON state of the relay 8 for a preset time.
The timer operating time of the timer drive circuit 7 is set to the time from the state where the voltage value between the terminals of the battery 2 is 90% to the fully charged state by the charging by the charger 1. Therefore, at the same time when the timer operation of the timer drive circuit 7 is stopped, a signal for stopping the charging of the battery 2 from the charger 1 is also output from the timer drive circuit 7 to the voltage / current adjusting means 5.

[Other Embodiment] Although the switching means for driving the cooling fan uses a relay in the above embodiment, it may be configured by using an active element such as a transistor instead of the relay. .

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is an overall side view showing an electric cart

FIG. 2 is a schematic block diagram showing a circuit such as a charger.

[Explanation of symbols]

 1 charger 2 battery 7 timer 8 driving means 9 cooling air blowing means

Claims (1)

[Claims] 1. A timer (7) which operates for a predetermined time at the end of charging of a battery (2) by a charger (1).
And a cooling air blowing means (9) for blowing cooling air to the battery (2), and the cooling air blowing means (9) is driven by a charging power source while the timer (7) is operating. Battery charging device provided with driving means (8)