JPH0270240A - Power supply for electronic equipment - Google Patents

Abstract

PURPOSE:To prevent an accident where the power supply is stopped in operation by switching over the power supply source to the other battery on detecting the drop of supply voltage. CONSTITUTION:Electric power is supplied from a plurality of batteries 2 to loads 3, 4 and 5 through a switching circuit 1. The supply voltage is detected by a voltage detection circuit 5. The voltage drop is detected by a circuit switching means 5, with which the switching circuit 1 is driven to switch over to another battery 2 for keeping on feeding the current.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a power supply device for electronic equipment.

2. Description of the Related Art Conventionally, some electronic devices that can be powered by batteries are equipped with a battery checker.

This battery checker is generally of the type that detects changes in battery voltage.

Problems to be Solved by the Invention Conventional electronic devices do not have spare batteries, so if the battery runs out during operation, not only will the device not be able to operate, but there is a risk of malfunctions such as memory contents being destroyed. Even if you check the battery voltage with a battery checker in advance, you cannot tell how long the battery will last. In other words, Figure 2 shows the discharge characteristics of a nickel-cadmium battery, and since this battery can be used with a stable voltage,
A voltage drop cannot be detected during a period when the voltage is stable. However, once the voltage begins to drop, it drops rapidly. Therefore, when using a battery that has discharge characteristics similar to this, although it is not limited to nickel-cadmium batteries, even if you check the battery voltage in advance, the power supply will be stopped during use, so you can use it with confidence. Can not.

Means for solving pressure points Claim 1 provides a switching section for connecting a load to one of a plurality of batteries, a voltage detection circuit is connected to the output side of the switching section, and the input side is connected to the voltage detection circuit. A circuit switching means is provided, the output side of which is connected to the switching section.

According to a second aspect of the present invention, there is provided a voltage detection circuit including a switching section for connecting a load to either of the two batteries, an input side connected to one of the batteries in parallel with the switching section, and an output side connected to the switching section. Established.

In the first aspect of the present invention, each time the voltage detection circuit detects a voltage drop in a battery connected to a load by the switching unit, the circuit switching means operates the switching unit to sequentially change the battery to be connected to the load.

In claim 2, when the voltage of one battery connected to the load by the switching unit decreases, the voltage detection circuit detects this state, and the detection signal directly operates the switching unit. Connect to the load.

Embodiment A first embodiment of the present invention will be described with reference to FIGS. 1 to 4. Reference numeral 1 designates a switching unit, a plurality of batteries 2 are connected to the input side of the switching unit 1, an actuator 4 is connected to the output side of the switching unit 1 via a driver 3, and a voltage detection circuit 5 is connected in parallel. It is connected to the. Between this voltage detection circuit 5 and the switching section 1, a circuit switching means C
A CPU 6 is connected to the CPU 6, a ROM 7 in which a program is written, and a RAM 9 in which change data is written, and the driver 3 and the display 9 are connected to the output side of the CPU 6. The driver 3, actuator 4, CPU 6, ROM 7, RAM 8, and display 9 are loads on the battery 2.

In the second configuration, power is supplied to the driver 3 from one of the batteries 2 via the switching unit 1.

Thereby, the actuator 4 is driven. The voltage of the battery 2 connected to the driver 3 is always detected by the voltage detection circuit 5.
Detected by As mentioned above, FIG. 2 shows the discharge characteristics of the Knickel cadmium battery 2.

Next, referring to the flowchart shown in FIG.
The circuit switching operation will be explained below. First, when all new batteries 2 are set, a signal indicating the completion of battery replacement work is inputted from an operation section (not shown), and N indicating the number of batteries 2 is written in the RAM 8. Voltage detection circuit 5 detects the voltage of battery 2. When the CPU 6 determines that the voltage detected by the voltage detection circuit 5 is below a certain value, the CPU 6 outputs a circuit switching command signal to the switching unit 1, and the switching unit 1, which has input this circuit switching command signal, performs a circuit switching operation and performs the following operation. Connect the battery 2 to the driver 3. Immediately after this operation, data N in RAM8 is changed to N-1.
Update to. In this way, the voltage of the battery 2 decreases and the operation of switching the switching unit 1 is repeated until N=0. During this time, the voltage detection circuit 5 continuously detects the voltages of the plurality of batteries 2 as shown in FIG. Further, the number of remaining batteries 2, that is, the value of N, is displayed on the display 9, and the batteries 2 are replaced when N=O.

Next, a second embodiment of the present invention will be described based on FIG. The same parts as in the previous embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, a switching unit 10 is provided to connect the driver 3 to either of the two batteries 2, and the input side is connected to one of the batteries 2 in parallel with the switching unit 10, and the output side is connected to the switching unit 10. A detection circuit 5 is provided, and an alarm section 11 is connected to the voltage detection circuit 5.

In such a configuration, when the voltage of the battery 2 connected to the redriver 3 by the switching unit 10 drops below a certain value, the voltage detection circuit 5 outputs a circuit switching command signal to the switching unit 10 and also issues an alarm. A signal II ( is outputted to the section 11. As a result, the switching section 10 connects the other battery 2 to the driver 3 on the one hand, and the alarm section 11 issues an alarm to replace the battery 2 on the other hand. In this state, Since the battery 2 to be used has been switched, it is possible to continue operating the electronic equipment. However, if the operation is interrupted when the alarm unit 11 issues an alarm, or if the operation is interrupted at a good point in the work, the battery 2 In this case, since the battery 2 used later is not completely exhausted, it is connected to the input side of the switching unit 1o while also being connected to the voltage detection circuit 5 so that it can be used immediately after replacing the battery. By doing so, it is possible to use the battery 2 to the end and avoid waste.

Effects of the Invention Since the present invention is configured as described above, in claim 1, the switching unit is operated by the circuit switching means every time the voltage detection circuit detects a voltage drop in the battery connected to the load by the switching unit. , the battery to be connected to the load can be sequentially changed, and in claim 2, when the voltage of one of the batteries connected to the load decreases by the switching unit, that state is detected by a voltage detection circuit, and the detection signal is detected. This has the effect of directly operating the switching unit, which allows the other battery to be connected to the load, thereby preventing the power supply from being stopped during operation in any case. has.

[Brief explanation of the drawing]

Figures 1 to 4 show a first embodiment of the present invention, where Figure 1 is a block diagram, Figure 2 is a graph showing the discharge characteristics of the battery, and Figure 3 is the detected voltage of the voltage detection circuit. FIG. 4 is a flowchart showing the circuit switching operation of the switching section, and FIG. 5 is a block diagram showing a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Switching part, 2...Battery, 3.4...Load, 5
...Voltage detection circuit, 6...Circuit switching means/load, 7
~9...Load, 10...Switching section

Claims (1)

[Claims] 1. A switching section for connecting a load to one of a plurality of batteries is provided, a voltage detection circuit is connected to the output side of the switching section, the input side is connected to the voltage detection circuit, and the output side is connected to the voltage detection circuit. 1. A power supply device for electronic equipment, comprising a circuit switching means connected to a switching section. 2. A switching section for connecting the load to either of the two batteries is provided, and a voltage detection circuit is provided whose input side is connected to one of the batteries in parallel with the switching section and whose output side is connected to the switching section. A power supply device for electronic equipment characterized by: