JPH0746838A - Electronic apparatus - Google Patents

Abstract

PURPOSE:To make it possible for a apparatus to correspond to diverse power sources without necessitating a space for installation, by making it have a structure wherein a DC-DC converter is so held as to be replaceable by a battery pack, and a construction wherein an arbitrary one of power source cords corresponding to the various power sources is connected removably to an input end of the DC-DC converter. CONSTITUTION:A space for holding a battery pack or a DC-DC converter 6 replaceably is provided in a power source holding part 4 of the main body 1 of a portable type personal computer. Besides, the DC-DC converter 6 is provided with an inlet connector part so that it is exposed outside, and a cord connection part of this inlet connector part is so designed that an input cord 8 for commercial power source or an input cord 9 for an automotive battery can be connected replaceably. By separating a cord part for input and making it removable in this way, an electronic apparatus can be driven by a desired power source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device such as a portable personal computer (hereinafter abbreviated as a personal computer) driven by a battery such as a built-in battery pack when it is carried, and particularly applicable to various power sources. Electronic devices.

[0002]

2. Description of the Related Art As semiconductor technology advances, electronic devices are becoming smaller, and along with this, electronic devices such as portable personal computers having a built-in power source such as a battery pack are increasing. In the above-mentioned portable electronic device, various power saving is performed in a circuit in order to enable a battery pack having a predetermined capacity to be used for a long time. However, the operating time of the battery pack is still, for example, that of a portable personal computer. 10 at best
It's about time. Therefore, these electronic devices are installed in the room A, etc.
When the C power source is used at an available place, it is common to use an AC adapter or the like provided outside the electronic device main body in order to prevent consumption of the battery pack capacity.

However, the external AC adapter and the like are relatively large blocks for personal computers, for example.
There is a drawback that it takes up a lot of space and is extremely disturbing when it is constantly used on a desk or the like. Therefore, in order to solve the above problems, an electronic device has been proposed in which an AC adapter can be attached in place of the battery pack in a space for accommodating the battery pack in the electronic device body.

[0004]

However, the method of accommodating the AC adapter in a replaceable manner with the battery pack as described above has recently been demanded because the target electronic equipment is limited to the battery pack and the commercial power source. It was impossible to use the in-vehicle battery in many cars.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems in the power source of the conventional portable electronic equipment, and can reduce the economical burden on the user and reduce the installation area. It is an object of the present invention to provide an electronic device equipped with a power supply means that can be used for various power supplies.

[0006]

In order to achieve the above object, the present invention has a structure in which a DC / DC converter is replaceable with a battery pack in an electronic device in which a battery pack is replaceable in an electronic device body. In addition, the DC / DC converter is configured such that any one of a plurality of input cords having different input voltages or input power sources is detachably provided at the input end thereof.

[0007]

As described above, according to the present invention, in the electronic equipment main body,
In an electronic device with a replaceable battery pack, DC
Since the / DC converter is provided so as to be replaceable with the battery pack, an installation place for placing the DC / DC converter becomes unnecessary. Further, since the input terminal of the DC / DC converter is detachably provided with any one of the input cords corresponding to a plurality of power sources having different input voltages or power source types, the user's economic burden is reduced. It can be reduced and can be used with various power sources.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is an external view of a portable personal computer showing an embodiment of an electronic device according to the present invention. In the figure, reference numeral 1 is a personal computer main body, 2 is a keyboard, 3 is a display, and a power source storage section 4 is provided as in the prior art. The vacant space for accommodating the DC / DC converter 6 is provided. The figure shows a state in which the DC / DC converter 6 is housed. Further, the DC / DC converter 6 is provided with the input connector portion of the DC / DC converter 6 exposed to the outside as shown in the figure, and the cord connection portion of the input connector portion has a commercial power input cord 8 and a vehicle-mounted device. The battery power input cord 9 is replaceably connected. If the input cord portion is separated and detachable as described above, the electronic device can be driven by a desired power source.

FIG. 2 is an external view showing an example of details of the commercial power input cord 8. A rectifier circuit is built in the connection box 81 in order to convert alternating current to direct current. In the figure, 82 is an AC plug and 83 is a DC /
It is an output connector portion that fits into the input connector portion 61 of the DC converter 6. FIG. 3 is an external view showing an example of details of the on-vehicle battery power input cord 9. In the figure,
91 is a connection box for wiring to the output connector section 93,
Reference numeral 92 is a cigarette lighter plug that fits with the joint portion of the vehicle battery.

FIG. 4 shows a DC / D housed in the power supply housing.
It is an external view which shows a detailed example of the C converter 6. As described above, the input connector portion 61 having the input terminal 62 can be fitted to the output connector portions 83 and 93 provided in the connection boxes 81 and 91. As will be described later, the DC / DC converter 6 has a built-in circuit for converting a DC voltage value into a predetermined value, and the output electrode 63 outputs the DC voltage converted into the predetermined value. This DC / DC converter 6 is operated from DC12V, which is the output voltage of the on-vehicle battery, or DC24.
It is possible to handle a wide range of input voltage from V to about 140 V DC after commercial power supply voltage rectification. FIG. 5 shows an example of an external view of the battery pack 5. The DC / DC converter 6 and the battery pack 5 have the same outer shape and the same output electrode structure so that they can be replaced.

FIG. 6 is a circuit diagram showing an embodiment of a DC / DC converter according to the present invention. Operation mode switching circuit 67
Is connected to the input terminal 62, detects the input voltage, controls the switching timing of the switching circuit 64 according to the detected voltage, and thereby controls the voltage output to the output electrode 63 to be constant. FIG. 11 is a diagram for explaining the operation of this circuit. Explaining with reference to FIGS. 6 and 11, T is a transformer, and a peak value of 1 / n of the input voltage peak value appears at the secondary side point a corresponding to the winding ratio (FIG. 11 ( See a)). In addition, the output end b is shown in FIG.
The sawtooth wave having the average level l _{1 in} (a) appears (the change amount of the sawtooth wave is made larger than the actual amount for the sake of explanation). As shown in FIG. 11B, when the switching circuit 64 is controlled so that the ON time is short, the charging time constant and the discharging time constant on the secondary side do not change, so the charging time becomes short and the discharge time becomes short. As the time increases, the average level l _{2 at} point b becomes lower than l ₁ . This embodiment utilizes such a principle, and such control is generally called a PWM (pulse width modulation) power supply. Also, 1
When the input power on the secondary side increases, the peak value at point a also increases in proportion thereto, as shown in FIG. 11 (c). At that time, the ON time of the switching circuit 64 becomes short as shown in (c). Thus, l ₃ = l ₁ . That is, when the operation mode switching circuit 67 detects a high voltage, the pulse width modulation circuit 66 generates a pulse having a narrow pulse width according to the voltage value. This pulse is widened by the driver 65, and the widened pulse is switched by the switching circuit 64 only during the period of the pulse width.
Turn on. Therefore, the output voltage can always be kept at a predetermined value despite the large fluctuation of the input voltage.

FIG. 7 is an external view showing another embodiment of the DC / DC converter according to the present invention. Instead of having means for detecting the input voltage, this embodiment has an input voltage selection switch 68 for indicating the input voltage. As shown in FIG. 8, the signal selected by the input voltage selection switch 68 is input to the pulse width modulation circuit 66, and is controlled as described above.

FIG. 9 is an external view showing another embodiment of the DC / DC converter according to the present invention, and this example shows a case corresponding to three kinds of input voltages. That is, the common input terminal 62g as the input terminal 62 and the input terminals 62a, 62b, 62c corresponding to the above three types of input voltages are provided.
As shown in FIG. 10, the respective input terminals are connected to a tap or the like corresponding to a predetermined number of turns on the primary side of the transformer T. That is, the secondary winding voltage is always set to a predetermined value by reducing the primary winding number ratio of high input voltage and increasing the primary winding number ratio of low input voltage. There is.

As described above, the electronic device to which the present invention is applied has been described by taking the portable personal computer as an example, but the present invention can be widely applied not only to the portable personal computer but also to electronic devices driven by a battery pack when being carried. You can Input voltage is also 2
It is apparent from the above description that the present invention is not limited to three or three. The pulse width modulation circuit 66 is not essential for the present invention and can be replaced with other means for keeping the output voltage at a predetermined value. Such a circuit
This is an improvement of the circuit normally provided in the feedback system, and therefore does not increase the cost.

[0015]

As described above, according to the present invention,
In the electronic device in which the battery pack is replaceable in the electronic device main body, the structure is provided in which the DC / DC converter is replaceable with the battery pack, so that the installation place for placing the DC / DC converter becomes unnecessary. Also, DC / DC
At the input end of the converter, it is configured so that any one of a plurality of input cords with different input voltages is detachably provided,
Alternatively, since it can be switched according to the input voltage, the user's economic burden can be reduced and various power sources can be supported.

[Brief description of drawings]

FIG. 1 is an external view showing an embodiment of an electronic device according to the present invention.

FIG. 2 is an external view showing a detailed configuration example of the commercial power supply input cord shown in FIG.

FIG. 3 is an external view showing a detailed configuration example of an on-vehicle battery power input cord shown in FIG.

FIG. 4 is an external view showing a detailed configuration example of the DC / DC converter shown in FIG.

FIG. 5 is an external view of a battery pack used in the electronic device according to the present invention.

FIG. 6 is a circuit diagram showing an embodiment of a DC / DC converter according to the present invention.

FIG. 7 is an external view showing another embodiment of the DC / DC converter according to the present invention.

8 is a circuit diagram showing an embodiment of the DC / DC converter shown in FIG.

FIG. 9 is an external view showing another embodiment of the DC / DC converter according to the present invention.

10 is a circuit diagram showing an embodiment of the DC / DC converter shown in FIG.

11 (a), (b) and (c) are DC / DC according to the present invention.
It is a wave form chart for explaining a converter.

[Explanation of symbols]

1 ... Personal computer main body, 2 ... Keyboard, 3
... Display, 4 ... Power storage unit, 5 ... Battery pack, 6
... DC / DC converter, 7 ... AC adapter, 8 ... Commercial power supply input cord, 9 ... In-vehicle battery power supply input cord, 51 ... Output electrode, 61 ... Input connector section, 62 ... Input terminal, 63 ... Output electrode, 64 ... Switching circuit, 65 ... Driver, 66 ... Pulse width modulation circuit, 67 ... Operation mode switching circuit, 68 ... Input voltage selection switch, 81 ... Connection box, 82
… AC plug, 83… Output connector part, 91… Connection box, 92… Cigar lighter plug, 93… Output connector part.

Claims (5)

[Claims] 1. An electronic device in which a battery pack is replaceably provided in an electronic device body, wherein a DC / DC converter is provided so as to be replaceable with the battery pack. 2. The DC / DC converter is configured such that an arbitrary one of a plurality of input cords corresponding to different types of input power supplies is detachably provided at an input end thereof. 1. The electronic device according to 1. 3. The DC / DC converter includes an operation mode switching circuit for automatically detecting an input voltage, and the operation mode switching circuit controls the voltage according to the input voltage of the DC / DC converter. The electronic device according to claim 1 or 2, characterized in that. 4. The DC / DC converter includes an input voltage selection switch, and the input voltage selection switch
3. The electronic device according to claim 1, wherein the electronic device is configured to perform voltage control according to an input voltage of the DC / DC converter. 5. The DC / DC converter has an input terminal capable of individually corresponding to each of a plurality of input codes, and is configured to select an input terminal according to an input voltage. Electronic device described.