JPH09180765A - Electronic equipment with charging function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable charging of an equipment which is provided with a DC power source jack of different polarity from a conventional one, by charging a rechargeable battery pack with the current supplied from an external power source connected to the DC power source jack when the rechargeable battery pack is installed. SOLUTION: A detector circuit 22 of a charging control circuit 21 detects whether a rechargeable battery pack 100 is in or not. In the case where the rechargeable battery pack 100 is in, a switching element 23 is turned on, and a charging resistor R1 is connected between a fixed piece 18 and a movable piece 17 of a DC power source jack 20. At this stage, when a DC power source plug is inserted in the DC power source jack 20 so as to be connected to an external power source, the rechargeable battery pack 100 can be appropriately charged through the charging resistor R1.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electronic device with a charging function.

[0002]

2. Description of the Related Art In portable electronic equipment such as a tape recorder mainly powered by a small primary battery such as a manganese dry battery or an alkaline dry battery, a Ni-Cd (Nickel-Cadmium) storage battery is provided in a battery chamber for the primary battery. Ni-MH (N
ickel-Metal Hydride) storage battery, Li-Ion (Litium-Io)
n) It is known that a secondary battery such as a storage battery can be mounted.

FIG. 6 is a diagram showing a configuration of a power supply section in such an electronic device. The figure shows a state where the rechargeable battery pack 100 including the secondary battery cells 14 is mounted in the battery chamber in the main body of the device. The rechargeable battery pack 100 has a + terminal 10, a − terminal 12, and a charging terminal 16, each of which has a + contact point 11, a − contact point 13, and a − contact point 13, which are provided in the battery chamber of the device body.
It is in contact with the charging contact 15.

In the main body of the equipment, the-contact 13 is connected to the GND line, the + contact 11 is connected to the fixed piece 18 of the DC power jack 20, and the charging contact 15 is connected to the power line (+ Vcc) via the charging resistor R1. ing. Further, the movable piece 17 of the DC power jack 20 is a power line (+ Vcc)
The center pin 19 is connected to the GND line.

In such a structure, when the DC power jack 20 is not connected to an external power source such as an AC adapter, the fixed piece 18 and the movable piece 17 of the DC power jack 20 come into contact with each other to recharge the battery pack 100. The + side is connected to the power supply line (+ Vcc). Therefore, the device operates using the rechargeable battery pack 100 as a power source.

On the other hand, when a DC power plug (not shown) is inserted into the DC power jack 20 to supply the external power,
The movable piece 17 and the fixed piece 18 of the DC power supply jack 20 are separated from each other, and the center pin 19 is placed on the negative side of the external power source.
Are respectively connected to the + side.

Inside the rechargeable battery pack 100, the positive terminal 10 and the charging terminal 16 are electrically connected, and
When an external power source is connected to the C power jack 20,
Power line (+ Vcc) → Charging resistance R1 → Charging contact 15 →
The current I1 flows through the route of charging terminal 16 → secondary battery cell 14 → −terminal 12 → −contact 13 → GND line to charge the secondary battery cell 14.

In the battery compartment described above, a rechargeable battery pack 100 is provided.
It is also possible to mount a primary battery such as a dry battery instead of the above, and FIG. 7 shows an electrical connection state when the dry battery 21 is connected in the battery chamber. As shown in the figure, since the charging contact 15 provided in the battery chamber and the dry battery 21 are not electrically connected to each other, a primary battery such as the dry battery 21 is erroneously charged. There is no such thing.

FIG. 8 is a diagram showing an example of the external shape of the above-mentioned rechargeable battery pack 100, in which the positive terminal 10 and the negative terminal 1 are connected.
2, each terminal of the charging terminal 16 is provided. The charging terminal 16 is provided at a portion corresponding to a valley between two dry batteries when two cylindrical dry batteries are placed side by side in the battery chamber, and is provided at a portion facing the charging terminal 16. The charging contact 15 provided does not come into contact with the dry battery 21.

Further, the rechargeable battery pack 100 is provided with a protrusion 22 having a special shape for preventing incorrect insertion,
Only when the shape of the concave portion provided at the position inside the battery chamber facing the projection 22 matches, the + and − terminals 10 and 12 of the rechargeable battery pack 100 and the + and − contact points 11 of the battery chamber,
It is formed so as to contact with 13. With this configuration, the rechargeable battery pack 100 is prevented from being connected with the wrong polarity.

[0011]

By the way, in recent years, the Japan Electronic Machinery Manufacturers Association has established a standard (EIAJ RC-532) for an external power plug / jack (for DC low voltage, uniform polarity type).
Due to the establishment of (0), the number of devices adopting the plug / jack of this standard is increasing, but in many cases, the polarity is different from that of the plug / jack conventionally adopted (the opposite). Therefore, a rechargeable battery pack designed according to the conventional standard polarity cannot be charged while it is installed in the main body, and a rechargeable battery pack having a charging terminal at a position different from the conventional one must be newly manufactured. It is necessary to add new manufacturing costs such as mold cost.

FIG. 9 is a diagram showing a structure of a power source unit having a DC power source plug having a polarity opposite to that of the structure shown in FIG. 6, and is constructed so that the rechargeable battery pack can be charged in the battery chamber. The electrical connection relationship in the case is shown.

A major difference from FIG. 6 is that the charging terminal 16 of the rechargeable battery pack 200 is connected to the negative side of the secondary battery cell 14. Along with this, the charging contact 15 provided in the battery chamber is connected to the GND line via the charging resistor R1.

In such a structure, when a DC power plug (not shown) is inserted into the DC power jack 20 in order to connect an external power source, the fixing piece 18 of the DC power jack 20 is inserted.
And the movable piece 17 are separated from each other, the center pin 19 is connected to the + side of the external power source, and the movable piece 17 is connected to the-side, so that the power supply line (+ Vcc) → the secondary battery cell 14 → the charging resistance R1 → GN
The current I1 flows through the path called the D line, and the secondary battery cell 1
4 is charged.

As described above, when the correspondence between the center pin 19 and the movable piece 17 of the DC power supply jack 20 and the polarity of the external power supply is changed, at least the internal connection relationship with the conventional rechargeable battery pack 100 is different. Battery pack 2
It is necessary to prepare 00.

10 to 12 are views for explaining the reason why the positions of the charging terminals of the rechargeable battery pack 200 are different. FIG. 10 is a diagram assuming a rechargeable battery pack 300 in which the positions of the charging terminals are the same as those of the rechargeable battery pack 100 shown in FIG. 6 and only the internal connection relationship is different. The method for connecting the DC power supply jack 20 to an external power supply such as an AC adapter to charge the battery is as described above with reference to FIG. 9, and thus the description thereof is omitted here.

FIG. 11 is a view showing a mounting state when the rechargeable battery pack 300 is mounted on the device having the structure shown in FIG. In such a mounted state, when the external power source is connected, the battery is not charged at all, and the charging resistor R1 is connected between the power source line (+ Vcc) and the GND line.
Since the charging resistor R1 usually has a low value of about several Ω to several tens of Ω, a large current flows through the charging resistor R1 to generate heat. Further, when the external power source is not connected, the charging resistor R1 consumes electric power and the battery is exhausted immediately.

FIG. 12 shows a rechargeable battery pack 10 shown in FIG.
FIG. 11 is a diagram showing a mounting state when 0 is mounted on the device having the configuration of FIG. 10. Even in such a mounted state, charging is not possible, and the charging resistor R1 is connected to the power line (+ V
Since it is connected between cc) and the GND line, inconveniences such as heat generation and remarkable battery consumption occur.

As described above, when a DC power supply jack having a polarity different from that of the conventional DC power supply jack is used, the conventional charging battery pack cannot be charged while being mounted in the battery chamber of the main body of the device. However, it is necessary to prepare a new rechargeable battery pack in which the position of the charging terminal and the internal connection are changed.

If the terminal position of the rechargeable battery pack is the same as that of the conventional one and the shape of the erroneous insertion preventing protrusion is changed, the problems of the configuration shown in FIGS. It is still necessary to prepare a rechargeable battery pack.

The electronic device with a charging function of the present invention has been made by paying attention to such a problem, and its purpose is to make any changes to the rechargeable battery pack designed according to the conventional device. It is an object of the present invention to provide an electronic device with a charging function that can be charged without being added to a battery mounting part in a device equipped with a DC power supply jack having a polarity different from the conventional one.

[0022]

In order to achieve the above object, the electronic device with a charging function according to the first aspect of the invention can be equipped with any one of a rechargeable battery pack with a charging terminal and a battery such as a dry battery. A DC power source in which external power is supplied to the device when the battery mounting part and the DC power plug are mounted, and power is supplied to the device from the battery mounted in the battery mounting part when the DC power plug is not mounted. The jack and the charging contact that is provided so as to contact the charging terminal of the charging battery pack when the charging battery pack is mounted on the battery mounting part, and the charging contact that is connected to the charging contact A detecting device that electrically detects the state, a switching device that turns ON / OFF in response to the detection result of the detecting device, and a battery device that connects via the switching device when an external power source is connected. And a charging current limiting means for supplying an appropriate charging current to the charging battery pack mounted in the battery mounting part, and an external power source connected to the DC power supply jack when the charging battery pack is mounted in the battery mounting part. The rechargeable battery pack is charged by the current supplied from the.

The electronic device with a charging function according to a second aspect of the invention is the electronic device with a charging function according to the first aspect of the invention, in which a resistor is used as the charging current limiting means. Also, the third
The electronic device with a charging function according to the invention is
In the electronic device with a charging function according to the invention described above, the transistor or the FET is used as both the detection means and the switching means.

That is, in the electronic device with a charging function according to the first aspect of the invention, the rechargeable battery pack is mounted in the battery mounting portion into which any one of the rechargeable battery pack with the charging terminal and the dry battery or the like can be mounted. At this time, when the charging contact comes into contact with the charging terminal of the charging battery pack, the detection means connected to the charging contact detects the mounting state of the charging battery pack in the battery mounting portion and corresponds to the detection result of the detection means. Then, the switching means is turned on / off. next,
When a DC power plug is attached to the DC power jack, external power is supplied to the device. At this time, the charging current limiting means supplies an appropriate charging current to the charging battery pack mounted in the battery mounting portion via the switching means. When the DC power plug is not attached to the DC power jack, power is supplied to the device from the battery attached to the battery attachment portion.

The electronic device with a charging function according to a second aspect of the invention is the electronic device with a charging function according to the first aspect of the invention, in which the charging current is limited by a resistor as a charging current limiting means.

The electronic device with a charging function according to a third aspect of the present invention is the electronic device with a charging function according to the first or second aspect of the invention, in which a charging battery pack is formed by a transistor or FET that also serves as a detecting unit and a switching unit. Is detected, and the ON / OFF operation corresponding to the detection result is performed.

[0027]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, an outline of an embodiment of the present invention will be described with reference to FIG. The figure shows the secondary battery cell 1
4 shows a state in which the rechargeable battery pack 100 including No. 4 is mounted in a battery chamber as a battery mounting portion in the device body. The rechargeable battery pack 100 has a + terminal 10, a − terminal 12, and a charging terminal 16, which are in contact with a + contact point 11, a − contact point 13 and a charging contact point 15 provided in the battery chamber of the device body. Further, in the device body, the − contact 13 is connected to the GND line, and the + contact 11 is the fixing piece 1 of the DC power supply jack 20.
8, the charging contact 15 is connected to the power supply line (+ Vcc) via the charging resistor R1. Further, the movable piece 17 of the DC power supply jack 20 is connected to the power supply line (+ Vcc), and the center pin 19 is connected to the GND line.

Although the above construction is the same as the conventional one, the present embodiment further includes a charge control circuit 21 composed of a detection circuit 22 as a detection means and a switching element 23 as a switching means. Then, the charging resistor R1 as the charging current limiting means is connected to the charging control circuit 2
The charging contact 15 is connected between the fixed piece 18 and the movable piece 17 of the DC power jack 20 via the switching element 23 in the charging control circuit 21 in the charging control circuit 21.
It is connected to the.

In the above configuration, the charge control circuit 21
The detection circuit 22 detects whether the rechargeable battery pack 100 is installed in the battery chamber, and the rechargeable battery pack 10 is detected.
When it is determined that 0 is attached, the switching element 23 is turned on, and the charging resistor R1 is connected between the fixed piece 18 and the movable piece 17 of the DC power jack 20. At this point, if a DC power plug (not shown) is attached to the DC power jack 20 in order to connect an external power source, the charging resistor R
Appropriate charging of the rechargeable battery pack 100 is performed via 1.

When the rechargeable battery pack 100 is not installed, the switching element 23 is in the OFF state. Therefore, when a primary battery such as a dry battery is installed in the battery chamber, it is erroneously charged. There is no such thing.

FIG. 2 is a diagram showing the configuration of the first embodiment of the present invention. In the figure, the + contact 11 provided in the battery chamber is connected to the power supply line (+ Vcc) in the device, and the power supply line (+ Vcc) is connected to the center pin 19 of the DC power supply jack 20. Further, the negative contact 13 provided in the battery chamber is connected to the fixed piece 18 of the DC power jack 20, and the movable piece 17 of the DC power jack 20 is the GN of the device.
It is connected to the D line. Further, the emitter of the NPN transistor Q1 is connected to the GND line, and the collector of the NPN transistor Q1 is connected to the fixed piece 18 of the DC power jack 20 via the charging resistor R1.
(-The same potential as the contact 13). A resistor R is provided between the base of the NPN transistor Q1 and the GND line.
3 is connected and the base of the NPN transmitter Q1 is connected to the charging contact 15 via the resistor R2.

The rechargeable battery pack 100 shown in FIG. 2 is the same as the rechargeable battery pack 100 shown in FIG. 6 and has a positive terminal 10, a negative terminal 12, a charging terminal 16, and a charging terminal 16
Are internally connected to the + terminal 10.

In the first embodiment, the charging resistor R1,
The resistor R2 and the NPN transistor Q1 form the charge control circuit 21 shown in FIG.
1 has the function of the detection circuit 22 and the function of the switching element 23.

In the above structure, the rechargeable battery pack 1
When 00 is mounted in the battery chamber, the charging contact 15 is connected to the power supply line (+ Vcc). Therefore, the current I1 flows into the base of the NPN transistor Q1 via the resistor R2, and the NPN transistor Q1 is turned on. When a DC power plug (not shown) is inserted into the DC power jack 20 to connect an external power source such as an AC adapter in this state, the power line (+ Vcc) → rechargeable battery pack 100 → charge resistance R1 → transistor Q1 → GND A current flows through a path called a line, and the rechargeable battery pack 100 is charged.

When the rechargeable battery pack 100 is not attached, the NPN transistor Q is connected via the resistor R2.
No current flows to the base of 1 and the base of the NPN transistor Q1 is connected to the GND line via the resistor R3. Therefore, the NPN transistor Q1 is never turned on. Therefore, the dry batteries in the battery chamber will not be accidentally charged.

According to the above-described first embodiment, a rechargeable battery pack designed for a conventional device can be used in a device equipped with a DC power supply jack having a polarity different from that of the conventional battery pack without any modification. It can be charged by installing it in the battery compartment. This eliminates the need for a new design of the rechargeable battery pack and the battery chamber, thereby reducing the manufacturing cost.

FIG. 3 is a diagram showing the configuration of the second embodiment of the present invention. In the second embodiment, an Nch MOS-FET (M1) is used as the detection circuit 22 and the switching element 23 shown in FIG. Other configurations are similar to those of the first embodiment.

According to this structure, the voltage divided by the resistors R2 and R3 connected between the charging contact 15 and the GND line is applied to the gate of the MOS-FET (M1). If it exceeds a certain value, MOS-FET
(M1) is turned on, and when it is below a certain value, it is turned off. That is, the MOS-FET (M1) is turned on only when the rechargeable battery pack 100 is mounted, and the rechargeable battery pack 100 can be charged by connecting the external power supply at this point.

Also in this embodiment, the same effect as that of the first embodiment is obtained. FIG. 4 is a diagram showing the configuration of the third exemplary embodiment of the present invention. In the third embodiment, the detection circuit 2 shown in FIG.
A comparator U1 is used as 2, and an NPN transistor Q1 is used as the switching element 23 shown in FIG.
Other configurations are similar to those of the first embodiment.

In such a structure, + Vcc and GND
The voltage divided by the resistors R4 and R5 connected between the lines is input to the-input terminal of the comparator U1,
Resistors R2 and R connected between the charging contact and the GND line
The voltage divided by 3 is input to the + input terminal of the comparator U1.

If the values of R2 to R5 are set in advance so that the voltage of the + input terminal becomes higher than that of the-input terminal when the rechargeable battery pack 100 is connected, the output terminal 24 of the comparator U1 Is the power line (+ Vcc)
Becomes a voltage close to that of the transistor Q1 via the resistor R6.
A current flows to the base of the transistor and the transistor Q1 is turned on. By connecting the external power supply at this point, the rechargeable battery pack 100 can be charged.

When the rechargeable battery pack 100 is not attached, the voltage of the + input terminal of the comparator U1 becomes the GND level via the resistor R3, and therefore becomes lower than the voltage of the-input terminal. As a result, the level of the output terminal 24 of the comparator U1 becomes close to the GND line,
The transistor Q1 is turned off.

Since the charging resistor R1 is intended to set the charging current to an appropriate value, a constant current circuit may be used instead of the resistor. Also in this embodiment, the same effect as that of the first embodiment is obtained.

FIG. 5 is a diagram showing the configuration of the fourth embodiment of the present invention. The embodiment of FIG. 4 is an embodiment in which the configuration of the first embodiment shown in FIG. 2 is changed so as to have an opposite polarity relationship. That is, the rechargeable battery pack 300 manufactured to conform to the configuration shown in FIG. 10 can be charged even when mounted in the battery compartment of a device having a DC power supply jack having a polarity opposite to that of FIG. Is.

Also in this embodiment, the same effect as that of the first embodiment is obtained. In the first, second, and fourth embodiments described above, since the detection circuit 22 and the switching means 23 shown in FIG. 1 are shared by one element, there is an effect that the configuration becomes simpler.

[0046]

According to the first and second aspects of the present invention, a DC battery having a polarity different from that of the conventional DC battery pack is designed without any modification.
The effect that it can be charged by being attached to the battery mounting portion in the device equipped with the power jack. According to the invention described in claim 3, in addition to the effect of the invention described in claim 1, there is an effect that the configuration is simpler.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining an outline of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a second embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a third exemplary embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a fourth exemplary embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a power supply unit in a conventional electronic device.

FIG. 7 is a diagram showing an electrical connection state when a dry battery is connected to the battery chamber.

FIG. 8 is a diagram showing an example of an external shape of a rechargeable battery pack.

FIG. 9 is a diagram showing a configuration of a power supply unit of an apparatus including a DC power supply plug having a polarity opposite to that of the configuration shown in FIG.

10 is a configuration diagram assuming a charging battery pack in which the positions of charging terminals are the same as those in the charging battery pack shown in FIG. 6 and only the internal connection relationship is different.

11 is a diagram showing a mounting state when the rechargeable battery pack is mounted on the device having the configuration shown in FIG.

12 is a diagram showing a mounted state when the rechargeable battery pack shown in FIG. 9 is mounted on a device having the configuration of FIG.

[Explanation of symbols]

10 ... + terminal, 11 ... + contact, 12 ...- terminal, 13 ...-
Contact, 14 ... Secondary battery cell, 15 ... Charging contact, 16 ... Charging terminal, 17 ... Movable piece, 18 ... Fixed piece, 19 ... Center pin, 20 ... DC power jack, 21 ... Charging control circuit,
22 ... Detection circuit, 23 ... Switching element, 100, 2
00, 300 ... Rechargeable battery pack, R1 ... Charging resistance.

Claims (3)

[Claims] 1. A DC battery plug having a charging terminal and a battery mounting portion into which any one of batteries such as a dry battery can be mounted, and an external power source supplied to the device when the DC power plug is mounted. When the battery pack is not installed, the DC power jack that supplies power to the device from the battery installed in the battery installation part, and when the rechargeable battery pack is installed in the battery installation part, contacts the charging terminal of the rechargeable battery pack. A charging contact provided to the charging contact, a detection means connected to the charging contact, for electrically detecting a mounting state of the charging battery pack in the battery mounting portion, and a switching means for turning on / off according to a detection result of the detecting means. When connecting an external power source, via the switching means,
Charging current limiting means for supplying an appropriate charging current to the rechargeable battery pack mounted in the battery mounting part, and when the rechargeable battery pack is mounted in the battery mounting part, D
An electronic device with a charging function, characterized in that a rechargeable battery pack is charged by a current supplied from an external power source connected to a C power jack. 2. The electronic device with a charging function according to claim 1, wherein a resistor is used as the charging current limiting means. 3. The electronic device with a charging function according to claim 1, wherein the transistor or the FET also serves as the detecting means and the switching means.