JPH07107660A - Electronic apparatus - Google Patents

Abstract

PURPOSE:To provide an electronic apparatus having a safe power supply part, from which dangerous current does not flow across the terminals until the power supply unit is mounted on the electronic apparatus. CONSTITUTION:A power supply unit has power supply terminals 7 for supplying the currents. The current from a rectifyer circuit is cut off with electrode gaps 12. When the power supply unit is not mounted, the current is not supplied directly to the power supply terminals 7. Meanwhile, conductive members 11 for short-circuiting the electrode gaps 12 other than receiving-side terminals 10 accepting the power supply a terminals 7 are arranged in a power-supply containing part. The electric power is supplied to the power supply terminals 7 of the power supply unit only when the power supply unit is mounted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic equipment, and more particularly, to power supply control of its power source.

[0002]

2. Description of the Related Art In portable electronic equipment such as a notebook personal computer and a portable word processor, a battery power supply unit containing a battery is attached to the main body to operate in a place where commercial power is difficult to obtain, and commercial AC is used on an indoor desk or the like. Is operated by using an AC adapter that converts the DC voltage into a predetermined DC voltage. Rechargeable nickel-cadmium batteries are generally used as battery power sources, but nickel-hydrogen batteries and 2
The capacity and current of lithium batteries are increasing. Further, a power supply unit has been proposed in which the AC adapter includes a step-down transformer, a rectifier circuit, a smoothing circuit, etc. and can be mounted as it is in the main body of the electronic device (JP-A-4-92381).
issue). On the other hand, the electric power required for electronic devices is also increasing because they are equipped with high-performance microprocessors and large-capacity memories. Therefore, both the power supply unit using the battery and the power supply unit using the AC adapter as described above tend to have a large capacity and a large current.

[0003]

However, in these power supply units, the terminals to which voltage is applied are exposed before mounting, and during storage or transportation, further, due to overcurrent due to short circuit between terminals during mounting, There was a risk of fire, burnout of batteries, rectifier circuits, etc., and electric shock.

The present invention has been made to solve the above-mentioned problems, and an electronic device having a safe power supply unit in which a dangerous current does not flow between terminals until the power supply unit is attached to an electronic device. Intended to provide equipment.

[0005]

In order to achieve the above-mentioned object, the present invention provides an electronic device in which a power supply unit can be removably mounted in a power supply housing, in which the power supply unit has a current greater than a predetermined value flowing between terminals. And a mounting detection unit that detects that the power supply unit is mounted. The current control unit performs current control to release the current limit between the terminals when mounting is detected. Configured.

[0006]

With this electronic device constructed as described above, current is controlled so that a predetermined amount of current does not flow between the terminals until the power supply unit is mounted, so that there is no risk of ignition, burnout of the power supply unit, electric shock, etc. You can avoid an accident.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of an electronic apparatus according to an embodiment of the present invention, in which a main body is provided with a liquid crystal display 1, a keyboard 2, a power source storage section 3 and the like. The power source storage unit 3 has a structure in which either a power source unit 4 using a battery or a power source unit 5 using an AC adapter is stored and used as a power source. Reference numeral 6 is an AC cord for connecting the power supply unit 5 with an AC adapter to a commercial AC.

FIG. 2 is a perspective view of a power supply unit mounted on the electronic device shown in FIG. Although an AC adapter is shown as a power supply unit in the figure, the same applies to a power supply unit using a battery power supply. 2 for power supply unit 5
There are two power supply terminals 7, and they come into contact with the terminals on the receiving side provided in the back of the power supply housing 3 when mounted on the main body of the electronic device.
The power supply unit 5 is further provided with a mounting detection hole 8 so that a conductive member provided inside the power supply housing 3 can be inserted therein.

FIG. 3 shows a contact relationship of terminals and the like when the power supply unit 5 shown in FIG. The power supply terminal 7 of the power supply unit is the power supply housing 3
The conductive member 11 which is in contact with the receiving side terminal 10 and is arranged further inside the power supply housing 3 penetrates the mounting detection hole 8 and is inserted into the electrode gap 12 to short-circuit the electrode. The electrode gap 12 has a gap before mounting, and the voltage from the rectifier circuit (not shown) is not applied to the power supply terminal 7.

Although the electrode gaps are short-circuited in the above embodiments, it goes without saying that similar detection and control can be performed using a microswitch. In this case, as shown in FIG. 4, the movable button of the micro switch 13 needs to be arranged so as not to project outside the power supply unit. In addition, it is necessary to provide a protruding portion 14 that responds to the pressure of the movable button at the back of the power source storage portion 3.

FIG. 5 is a perspective view of a power supply unit showing another embodiment of the present invention. Although the battery power supply is shown as the power supply unit, the same applies to the case of the AC adapter power supply unit. The battery power supply unit 4 has a detection terminal 15 in addition to the two power supply terminals 7, and is configured to detect attachment and control the current by the circuit shown in FIG. Needless to say, there is a receiving side terminal (not shown) for receiving the power supply terminal 7 and the detection terminal 15 inside the power supply housing 3.

FIG. 6 shows a switching circuit using a transistor as an example of mounting detection and current control. Before the power supply unit is attached, the detection terminal 15 is pulled up to the anode potential of the battery, so that it is at “H level”, the switching transistor TR is in the off state, and the voltage of the anode of the power supply terminal 7 is Does not appear. When the power supply unit is attached to the main body of the electronic device and the power supply terminal 7 and the detection terminal 15 come into contact with the corresponding terminals on the main body receiving side,
The GND terminal on the main body side and the detection terminal 15 come into contact with each other, and the terminal becomes "L level".
R is turned on and a voltage is output to the anode of the power supply terminal 7.

A voltage is applied to the detection terminal 15 through the resistor R2 before mounting even when there is no load. However, R
By setting the values of 1 and R2 to be large values, the current that flows at the time of short-circuiting with other terminals becomes very small, and there is no problem in terms of safety.

In the above embodiments, the method of using electrical contact by a conductive member or a micro switch for detecting mounting and controlling current, and the potential detection by transistor and current control by resistance have been described. Are not limited to these examples. For example, the power supply terminal of the power supply unit may be floated from the power supply line by an elastic member such as a metal spring or an air spring when the power supply unit is not installed, and may be brought into contact with the power supply line by pressure response when the power supply unit is installed. A switch may be configured by disposing a permanent magnet on the metal piece and contacting the metal piece with the attraction force of the magnet.

[0015]

As described above, in the electronic device according to the present invention, before the power supply unit is attached to the device, a current more than a predetermined amount does not flow to the power supply terminal of the power supply unit, so that the power supply unit is attached or stored. It is possible to prevent the power supply terminal from short-circuiting during transporting, and to prevent an overcurrent from flowing, and to avoid the risk of electric shock.

[Brief description of drawings]

FIG. 1 is a perspective view of a power supply and an electronic device showing an embodiment of the present invention.

FIG. 2 is a perspective view of an AC adapter power supply unit showing an embodiment of the present invention.

FIG. 3 is a diagram for explaining the connection between the AC adapter power supply unit shown in FIG. 2 and the terminals of the power supply housing.

FIG. 4 is a diagram for explaining the connection between the battery power supply unit and the terminals of the power supply housing according to the embodiment of the present invention.

FIG. 5 is a perspective view of a battery power supply unit showing an embodiment of the present invention.

FIG. 6 is a circuit diagram illustrating the principles of mounting detection and current control in the present invention.

[Explanation of symbols]

1 Liquid Crystal Display 2 Keyboard 3 Power Supply Section 4 Battery Power Supply Unit 5 AC Adapter Power Supply Unit 6 AC Cord 7 Power Supply Terminal 8 Hole for Detecting Mounting 10 Receiving Side Terminal 11 Conductive Member 12 Electrode Gap 13 Micro Switch 14 Projection 15 Detection Terminal

Claims (4)

[Claims] 1. An electronic device in which a power supply unit is detachably mountable in a power supply housing, wherein the power supply unit is equipped with a current control means for restricting a current more than a predetermined value between terminals and a power supply unit. An electronic device, comprising: mounting detection means for detecting, wherein the current control means performs current control to release a current limitation between terminals when mounting is detected. 2. The electronic device according to claim 1, wherein the control means and the detection means are performed by contact and non-contact of a conductive member. 3. The electronic device according to claim 1, wherein the control means and the detection means are composed of electronic circuits. 4. The electronic device according to claim 1, wherein the power supply unit is an AC adapter that converts a battery power supply or a commercial alternating current into a predetermined voltage and rectifies it.