JPH0389816A - Electronic apparatus - Google Patents

Abstract

PURPOSE:To contrive to decrease the cost of an electronic apparatus through employment of a small capacity and low cost second power supply by providing a control means for inhibiting the charge of a storage battery by the second power supply, when an electric load due to the working condition of the electronic apparatus is large. CONSTITUTION:When a controller 6 outputs a high-level control signal to an output port P0, transistors(Tr) T2 and T 1 are turned ON to enable charging of a nickel-cadmium battery; and when the controlled part 6 outputs a low-level control signal, Trs T2 and T1 are turned OFF to inhibit charging. Also, an adapter connection detector 5 for detecting whether an adapter 2 is connected with a power jack 3 or not, is provided and the output of the detector 5 is connected with the input port P1 of the controller 6. In the normal mode of an electronic apparatus, charging of the battery 1 is inhibited while an actuator 8 operates when the adapter 2 is connected, and charging is permitted only when the actuator 8 does not operate. When the adapter 2 is connected, therefore, driving of the actuator 8 and charging of the battery 1 are not performed simultaneously.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to electronic equipment, and in particular uses a storage battery as a first power source and a second power source other than the storage battery, and uses the second power source to operate the storage battery. This invention relates to an electronic device configured to be able to charge a battery.

[Prior art] As this type of electronic equipment, rechargeable storage batteries such as nickel-cadmium batteries (hereinafter abbreviated as nickel-cadmium batteries) and A
Electronic devices that use a C-DC adapter as a power source are known. When an AC-DC adapter is connected to such an electronic device and power is being supplied by the AC-DC adapter, the NiCd battery is charged by the power of the AC-DC adapter. In order to prevent NiCd batteries from being overcharged beyond full charge in such electronic devices, the control section of the electronic device detects the terminal voltage of the NiCd battery, and when the terminal voltage exceeds a predetermined value, has a configuration that prohibits charging of NiCd batteries.

[Problem to be solved by the invention] However, in the configuration of the conventional electronic device as described above,
The capacity of the AC-DC adapter, that is, the power supply capacity, must be set to a value that corresponds to the maximum electrical load due to the operating state of the drive unit of the electronic device plus the load for charging the NiCd battery. However, there was a problem in that the capacity of the AC-DC adapter had to be increased.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems related to power supply capacity in this type of electronic equipment.

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, a storage battery as a first power source and a second power source other than the storage battery are used, and the second power source is used to power the storage battery. In the electronic device configured to be able to charge the storage battery, a configuration is adopted in which a control means is provided for prohibiting charging of the storage battery by the second power source when the electrical load due to the operating state of the electronic device is large.

[Function 1] According to such a configuration, when the electrical load of the electronic device is large depending on the operating state of the electronic device, charging of the storage battery by the second power source is prohibited.

[Example] DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIG.

FIG. 1 shows the overall configuration of an electronic device according to an embodiment of the present invention.

As shown in Fig. 1, the electronic device of this embodiment uses a NiCd battery 1 as a rechargeable storage battery as a power source, and an AC-DC adapter (hereinafter referred to as an adapter) that converts the AC voltage of a commercial power supply into a predetermined DC voltage and outputs it. omitted) 2 is used. adapter 2
is detachably connected to the power supply line of the main body of the electronic device via the power jack 3. The power supply line is switched through the power jack 3 so that when the adapter 2 is not connected, power is supplied by the NiCad battery 1, and when the adapter 2 is connected, the power is supplied by the adapter 2.

Power is supplied from the NiCad battery 1 or the adapter 2 to each part of the electronic device via a power supply circuit 7. This power supply circuit 7 is a well-known circuit that performs voltage transformation, voltage regulation, etc. A control unit 6 that controls the entire electronic device from this voltage circuit 7
For example, power is supplied to the drive unit 8 and other parts of a printer or the like.

The control unit 6 is composed of a microcomputer including a CPU as a microprocessor element, ROM and RAM as memories, and input/output board elements. The drive section 8 is controlled by the control section 6. A keyboard 9 is also connected to the control unit 6, and various commands and data are input to the control unit 6 by operating the keyboard 9. Further, a buzzer 10 is connected to the control unit 6 for issuing an alarm, which will be described later.

Furthermore, in this embodiment, the control unit 6 connects or disconnects the charging path of the NiCd battery l, which is composed of the lead IIL connected to the power supply line, to the NiCd battery l to permit or prohibit charging of the NiCd battery l by the adapter 2. A switching circuit 4 is provided for this purpose. The switching circuit 4 includes transistors T1. Ti and bias and current limiting resistors R2 to R
It consists of 5. The emitter collector of the transistor T is connected in series between the lead wire and the NiCd battery l via a protective diode D, and the base is connected to the collector of the transistor T2 via a resistor R1. The base of the transistor T2 is connected to the output port PO of the control unit 6 via a resistor R6, and the emitter is grounded.

With such a configuration, the control unit 6 outputs a high-level control signal to the output port PO, thereby controlling the transistor T2.
is turned on, transistor T is turned on, the charging path is crossed, conduction is established between the NiCd batteries 1, and the NiCd battery 1 can be charged. In addition, by the control unit 6 outputting a low level control signal to the output port PO,
Transistor T2 is turned off, transistor T is turned off, lead ML and NiCd battery 1rWi are cut off, and the NiCd battery l cannot be charged. That is, charging is prohibited.

Further, the electronic device of this embodiment is provided with an adapter connection detector (hereinafter abbreviated as a detector) 5 that detects whether or not the adapter 2 is connected to the power jack 3, and its output is input to the controller 6. Connected to boat Pl. The detector 5 is composed of a switch S operated by connecting the adapter 2 and a pull-up resistor R. When the adapter 2 is not connected to the power jack 3, the high level voltage of the power line is applied to the output signal line of the detector 5 via the resistor R1, and the output signal of the detector 5 becomes high level. . Also, adapter 2 is power jack 3
When connected to the switch S, the switch S is operated and closed, and the detector 5
The output signal line of the detector 5 is grounded via the switch S, and the output signal of the detector 5 becomes low level.

Next, control operations related to permission and prohibition of charging of the NiCd battery 1 in the electronic device of this embodiment having the above configuration will be described below.

In the normal operation mode of the electronic device of this embodiment, adapter 2
Charging of the NiCd battery l is prohibited while the drive unit 8 is operating with the drive unit 8 connected, and charging is permitted only when the drive unit 8 is not operating. This is carried out as follows under the control of the control section 6 whose processing procedure is shown in FIGS. 2 and 3. Note that the control processing of the control section 6 is performed according to the *qm program of the microcomputer constituting the control section 6.

First, FIG. 2 shows an initialization process performed by the control section 6 when a power switch (not shown) of the electronic device is turned on or reset. In step Sl of this initialization process, the control section 6 initializes the output signal data of each output port, and outputs the output port PO that controls the switching circuit 4, which initializes each section.
The initial control signal is set to a high level, whereby the lead wires and the NiCd battery IM are brought into conduction, and the NiCd battery I is placed in a state where it can be charged. That is, charging of the NiCad battery 1 is permitted at the time of initialization.

Next, the control section 6 performs the processing shown in FIG. 3 at an appropriate timing.

In the process shown in FIG. 3, first, in step Sll, data of the input port Pl into which the output of the detector 5 is input is read.

Next, in step 512, it is determined whether or not the adapter 2 is connected based on the input port-PI data. As described above, if the data on the input port pt is at a high level, the adapter 2 is not connected, and if the data is at a low level, the adapter 2 is connected. If adapter 2 is not connected, the process jumps to step S14 and the output boat PO
A low level signal is output to inhibit charging of the nickel cadmium battery l, and the process ends.

On the other hand, if adapter 2 is connected, step S1
In step 3, it is checked whether the drive section 8 is in operation. If it is in operation, charging of the NiCd battery 1 is prohibited in step S14, and the process ends.

On the other hand, if the drive section 8 is not in operation, a high-level signal is output to the output boat PO in step S15 to permit charging of the NiCd battery I, and the process ends.

As described above, in the normal operating mode of the electronic device of this embodiment, charging of the NiCad battery 1 is prohibited when the adapter 2 is not connected. Further, while the adapter 2 is connected, charging is prohibited if the drive unit 8 is in operation, and charging is permitted if the drive unit 8 is not in operation.

Therefore, in the electronic device of this embodiment, the drive unit 8 is not driven and the NiCd battery l is charged at the same time when the adapter 2 is connected.
The capacity can be set to be smaller than the capacity corresponding to the maximum load when driving the drive section plus the load due to charging of the NiCd battery as in the conventional case. Moreover, a small-capacity and inexpensive adapter can be used as the adapter 2, and the cost of the entire electronic device can be reduced.

By the way, in this embodiment, a charging priority mode can be set in which charging of the NiCd battery 1 is given priority over driving of the drive unit 8 in accordance with the operation of a predetermined key on the keyboard 9. In the charging priority mode, the control section 6 performs the processing shown in FIG. 4 as follows.

That is, first, in step 5211L:J3, data of the input port P1 of the detector 5 is read, and in step S22, it is determined based on the data whether or not the adapter 2 is connected.

If adapter 2 is connected, step S2
At step 3, a high-level control signal is output to the output boat PO to permit charging, and the process ends.

On the other hand, if the adapter 2 is not connected, the buzzer 10 is sounded in step S24 to prompt the user of the electronic device to connect the adapter 2, and the process ends.

Although not shown in the flowchart of FIG. 4, when the charging priority mode is set and a command to drive the drive unit 8 is input by operating the keyboard 9, the drive unit 8 is not driven and the buzzer 10 is activated. The drive unit 8
The user shall be notified that this operation is not possible.

By using the charging priority mode as described above, it is possible to charge the NiCd battery 1 reliably and without error.

[Effects of the Invention] As is clear from the above description, according to the present invention, a storage battery as a first power source and a second power source other than the storage battery are used, and the storage battery can be charged by the second power source. In the electronic device configured as above, a configuration is adopted in which a control means is provided for prohibiting charging of the storage battery by the second power source when the electrical load due to the operating state of the electronic device is large. If the electrical load of the electronic device is large depending on the operating state, charging of the storage battery by the second power source is prohibited, so the capacity of the second power source can be set smaller than before, making it possible to use the second power source with a small capacity and low cost. The excellent effect of reducing the cost of electronic equipment can be obtained by using the same method.

[Brief explanation of drawings]

FIG. 341 is a block diagram showing a configuration related to charging control of a NiCd battery in an electronic device according to an embodiment of the present invention, FIG. 2 is a flowchart of initialization processing by the control unit 6 in FIG. 1, and FIG. A flowchart of charging control by the control unit in the normal operation mode, and FIG. 'M4 is a flowchart of charging tflJ control in the charging priority mode.

Claims (1)

[Claims] 1) In an electronic device that uses a storage battery as a first power source and a second power source other than the storage battery, and is configured such that the second power source can charge the storage battery, electricity is generated depending on the operating state of the electronic device. When the target load is large, the second
An electronic device characterized in that it is provided with a control means for prohibiting charging of the storage battery by the power source of the electronic device.