JPH063704B2 - Charge control relay - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement of a storage battery charging device.
Recently, the development of automated guided vehicles has been vigorous, and along with this, high reliability of the automatic charging device for storage batteries for such vehicles is desired.

2. Description of the Related Art The problems that affect the performance and reliability of an automatic charging device are the charging control relays that control the charging device. However, in the conventional charge control relay, the electronic parts of the components and the output relay are often out of order, and the storage battery is often overcharged or damaged.

Means for Solving the Problems The present invention is to provide a monitoring circuit in the output circuit of the charging control relay so as to immediately stop the charging when an electronic component or an output relay fails. More specifically, the output relay is turned on and held by charging and discharging the capacitor and the charging current thereof, and the failure of the output relay circuit is detected by monitoring the potential of the capacitor.

Embodiment FIG. 1 is a circuit diagram showing an embodiment of the charging control relay of the present invention, 1 is an output relay coil, 2 is a switching transistor, 3 is a capacitor, and 1, 2, 3 are connected in series with each other. ing. Reference numeral 4 denotes a capacitor discharging transistor which is ON / OFF controlled by a microcomputer chip 5 described later, and is connected in parallel to the capacitor 3. 5
Is a microcomputer chip for charge / discharge control, and 6 is an LED for displaying a failure. Reference numerals 7 and 8 are resistors and reference numeral 9 is a zener diode, and these 7, 8, and 9 constitute a constant voltage power source for the microcomputer chip 5. Reference numeral 10 is a charge push button switch, 11 is a stop push button switch, 12 is an oscillator for controlling the microcomputer chip 5, and 13 is an output relay contact.

FIG. 2 shows a circuit example of a charging device using the charging control relay of the present invention, 21 is a power switch, 22 is a rectifying circuit, 23 is a fuse, 24 is a storage battery, 25 is a charging control relay,
26 is a contact of the charge control relay.

Referring to FIG. 1, when the push button 10 for charging is pressed, the microcomputer chip 5 is started and the switch transistor 2 is turned on.
N, the discharge transistor 4 of the capacitor 3 is turned ON-O.
FF operation, output relay coil 1 is excited, its contact
Close 13 After a predetermined time has elapsed, the microcomputer chip 5 operates, the switching transistor 2 and the discharging transistor 4 of the capacitor 3 are turned off, and the output relay contact 13 is opened.

Referring to FIG. 2, when the contact 26 of the charge control relay is closed, the power switch 21 is closed and the storage battery 24
Start charging. Charge control relay after a predetermined time
When 25 operates and its contact 26 opens, the power switch 21 opens to stop charging.

However, as described above, if a component of the charge control relay 25 fails during charging and the contact 26 remains closed, the storage battery 24 will be overcharged or damaged.

In order to prevent this, the present invention detects the failure of the output relay circuit by monitoring the potential at the point b'on the + side of the capacitor 3 in FIG. 1 by the microcomputer chip 5. If the potential at the point b'is continuously low (potential of the − line) during the operation of the charge control relay, the output relay coil 1 is broken or the switch transistor 2 is opened, or the capacitor 3 or the discharge transistor 4 is used. Is the case of short circuit. When the potential at the point b'is high, it means that the switching transistor 2 is short-circuited or the discharging transistor 4 is open. During the operation of the charge control relay, it is detected that the potential at point b'becomes low or high continuously, and the switching transistor 2 or the discharging transistor 4 of the capacitor 3 is turned off, and the contact 13 of the output relay is turned on. The LED 6 is opened and the LED 6 is turned on to display the failure. Further, when the microcomputer chip 5 malfunctions or the oscillator 12 fails, the ON / OFF control of the discharge transistor 4 is disabled and the contact 13 of the output relay can be opened.

Advantageous Effects of Invention As described above, the present invention provides a highly reliable charging control relay by constantly monitoring the output circuit that is prone to failure even in the constituent circuits of the charging control circuit.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a charging control relay of the present invention, and FIG. 2 is a circuit diagram showing a circuit example of a charging device. 1 ... Output relay coil, 5 ... Microcomputer chip, 6 ... LE
D, 12 ... Oscillator, 13 ... Output relay contact, 22 ... Rectifier circuit,
24 ... Storage battery, 25 ... Charging control relay, 26 ... Charging control relay contact

Claims (1)

[Claims] 1. A coil of an output relay, a switching transistor whose base is connected to an output port of a microcomputer, and a capacitor are connected in series, and a base is an output port different from the output port of the microcomputer. And a capacitor discharge transistor which is connected to the capacitor and is controlled so as to intermittently drive the base by appropriately dividing the oscillation of the control oscillator of the microcomputer. A charge control relay, which is a relay and is configured to detect a failure by monitoring a potential of the capacitor at an input port of the microcomputer.