JPH04236133A - Charging device - Google Patents

Abstract

PURPOSE:To realize an inexpensive charging device which can cope with the abnormality of a charging control circuit and uses a less number of parts. CONSTITUTION:A CPU 3 for controlling charging outputs a charging start signal to a charging circuit 4 and, at the same time, sends a pulse of a fixed period to a multivibrator 5. The multivibrator 5 issues a charging permit signal to the circuit 4 upon detecting the pulse from the CPU 3 and the circuit 4 starts charging of a battery 2. When abnormality occurs in the CPU 3 and the output pulse to the multivibrator 5 stops, the charging permit signal becomes 'L' and the circuit 4 stops the charging 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 charging device for rapidly charging a storage battery.

0002

2. Description of the Related Art In recent years, with the spread of small personal computers, there has been a strong demand for charging devices for rapidly charging nickel-cadmium storage batteries, etc., not only to reduce the cost of the device but also to ensure its safety.

[0003] A conventional charging device will be explained below. FIG. 3 is a block diagram of a conventional charging device, in which 1 is a charging device, 2 is a storage battery, 3 is a 4-bit CPU that controls the operation of the charging device 1, and 4 is a storage battery according to a charging start signal issued from the CPU 3. 2 is a charging circuit that performs charging, 6 is a power supply unit that supplies DC power to the charging circuit 4, and 7 is a timer that starts operation according to instructions from the CPU 3 and issues a charging stop signal to the charging circuit 4 after a certain period of time has elapsed. be.

The operation of the conventional charging device configured as described above will be explained below. The CPU 3 issues a charging start signal to the charging circuit 4 and also commands the timer 7 to start its operation. Then, the timer 7 starts operating, and the charging circuit 4 starts charging the storage battery 2 based on the DC power supplied from the power supply section 6. The CPU 3 detects the end of charging by monitoring the voltage of the charging side terminal of the charging circuit 4 to the storage battery 2, and causes the charging circuit 4 to end the charging,
At the same time, the operation of the timer 7 is also stopped.

[0005] If it becomes impossible to detect the end of charging for some reason, such as when the CPU 3 goes out of control during charging, the timer 7 outputs a charging stop signal to the charging circuit 4 after a certain period of time has passed from the start of charging. However, charging will be forcibly stopped.

[0006]

[Problems to be Solved by the Invention] However, in the conventional charging device described above, the timer circuit has a large number of parts.
This had the problem of being expensive. SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive charging device with a small number of parts, which can solve the problems of the conventional technology and deal with abnormalities in the charging control circuit.

[0007]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a charging stop that detects an abnormality in a control means for controlling battery charging, such as the start and end of charging, and stops charging the battery. means.

[0008]

[Operation] According to the present invention, charging is performed while the control circuit is operating normally, and when an abnormality occurs in the control circuit, the charging stop means detects the abnormality and stops the charging means. to forcefully terminate charging.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. Note that explanations of parts that overlap with the conventional example will be omitted.

FIG. 1 is a block diagram of a charging device according to an embodiment of the present invention, in which 3 is a 4-bit CPU that controls the operation of the charging device 1, and 5 is a multivibrator. In this embodiment, the charging means of the present invention is realized by the charging circuit 1, the control means by the CPU 3, and the charging stop means by the multivibrator 5.

The operation of this embodiment will be explained below using the timing chart of FIG. First, CPU3
At the timing indicated by , a signal 1 instructing the charging circuit 4 to start charging is issued, and a signal 2, which is a constant cycle pulse, is issued to the multivibrator 5. Then, the multivibrator 5 activates the charging circuit 4 at the timing shown by arrow A.
Outputs a charging permission signal to The charging circuit 4 receives the signal 1 from the CPU 3 and starts charging the storage battery 2 when the charging permission signal is "H".

[0012] If it becomes impossible to control charging and detect the end of charging for some reason, such as when the CPU 3 goes out of control during charging, the signal 2 from the CPU 3 stops as shown by arrow C, and the multivibrator 5 no longer operates, and the charging permission signal becomes "L" as shown by arrow D. The charging circuit 4 forcibly ends charging the storage battery 2 when the charging permission signal becomes "L".

As described above, in this embodiment, charging can be stopped when the CPU is abnormal with a simple circuit configuration.
It is possible to reduce the number of parts and reduce costs.

[0014]

According to the present invention, since a means for detecting abnormality in the CPU and stopping charging of the storage battery is provided, an inexpensive charging device with a small number of parts can be realized.

[Brief explanation of the drawing]

FIG. 1: Block diagram of a charging device in an embodiment of the present invention.

[Fig. 2] Timing chart showing the operation of the charging device of the embodiment

[Figure 3] Block diagram of a conventional charging device

[Explanation of symbols]

1 Charging device 2 Storage battery 3 CPU 4 Charging circuit 5 Multivibrator 6 Power supply section 7. Timer

Claims (2)

[Claims] 1. A charging device that charges a battery; a control device that sends a charging start signal to the charging device, monitors the charging state, and issues an end signal when charging is completed; A charging device characterized by comprising: a charging stop means for sensing an abnormality in the control means and stopping the charging means. 2. The charging device according to claim 1, wherein the abnormality is determined when the signal output from the control means is no longer output.