JPH11122832A - Charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To charge in a non-contact way a secondary battery integrated into an electronic appliance, without providing any sensing terminal, etc., on the outer surface of the electronic appliance side, by providing a charging-side sensing coil oppositely to a charged-side sensing coil connected in parallel with the secondary-side charging coil of the electronic appliance, and by sensing the presence of the putting of the electronic appliance on a charging table. SOLUTION: When an appliance (B) is absent on a charging table (A), a charge controlling circuit 13 outputs a signal (a) intermittently to a switch SW1 to excite intermittently a primary-side charging coil L1 . Then, when putting the appliance B on the charging table A, generating a DC voltage (b) in the output circuit of a secondary-side charging coil L2 , a charged-side sensing coil L4 is excited to generate a signal (c) in a charging-side sensing coil L3 . At this time, the charge controlling circuit 13 recognizes the putting of the appliance B on the charging table A and outputs the signal (a) to close continuously the switch SW1 and excite continuously the primary-side charging coil L1 . As a result, generating the continuous DC voltage (b) in the output circuit of the secondary-side charging coil L2 , a secondary battery BT is charged by a charge controlling circuit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for electronic equipment and portable communication equipment using a secondary battery as a power supply.

[0002]

2. Description of the Related Art Recently, mobile phones and PHS (Person)
al Handyphone System), as well as portable communication terminals premised on portable use, as well as cordless telephones used in homes, electric razors, electric toothbrushes, and many other electronic devices with built-in secondary batteries. Are often seen.

[0003] When charging a secondary battery incorporated in this kind of electronic equipment, it is usually placed in a predetermined position of a dedicated charger to provide a charging device provided in both the equipment and the charger. The terminals are brought into contact with each other so that the secondary battery is charged.

[0004]

However, since the charging terminal has a structure exposed on the outer surface of the device, it is disadvantageous not only for making the portable device to have a waterproof structure but also for adhering water droplets and the like. As a result, the terminals may be short-circuited.

[0005] Recently, in a variety of electronic devices incorporating a secondary battery, a system employing a non-contact type charger utilizing electromagnetic induction has become mainstream. However, in the non-contact type charger, the electric current is always supplied to the primary coil which is opposed to the secondary coil on the electronic device side by mounting the electronic device, and the electric power is constantly consumed. It is in a state. Therefore, there is a problem that not only wasteful power is consumed but also a metal such as a clip near the primary coil may generate heat.

The present invention has been made in view of the above-described circumstances, and an object of the present invention is to mount the device without providing a detection terminal or the like on the outer surface of the device to be charged. It is an object of the present invention to provide a charging device capable of detecting this only when the battery is placed, and performing charging without contact.

[0007]

According to the first aspect of the present invention,
By mounting an electronic device having a built-in secondary battery as a power source, the secondary charging coil connected to the secondary battery is supplied with power from the primary charging coil in a non-contact manner, and In a charging device for charging a battery, a charging device is disposed at a position facing a charging-side detection coil connected in parallel to the secondary-side charging coil of an electronic device, and detects the presence or absence of the charging-side detection coil. Control means for detecting the presence / absence of the electronic device based on the output of the charging side detection coil, a switch for interrupting the current flowing through the primary side charging coil, and an output of the charging side detection coil, for intermittently controlling the switch And characterized in that:

[0008] With this configuration, without providing a terminal or the like for detection on the outer surface of the electronic device to be charged, the device can be reliably detected only when the device is mounted.
Charging can be performed without contact.

According to a second aspect of the present invention, a portable communication device having a built-in secondary battery is mounted as a power source, so that electric power is supplied from the primary coil in a non-contact manner to the secondary coil of the secondary battery. In a charging device that supplies and charges the secondary battery,
A first communication device that communicates with the portable communication device and a presence / absence detection of the portable communication device based on a signal indicating the electric field strength of the portable communication device obtained from the communication device unit;
Detecting means, a second detecting means disposed at a position where the portable communication device is mounted, and detecting presence / absence of the portable communication device; a switch for interrupting a current flowing through the primary coil; And control means for intermittently controlling the switch based on the detection result of the second detection means.

[0010] With this configuration, the portable communication device to be charged can be reliably detected only when the device is placed without providing any special structure such as a terminal for detection. Charging can be performed without contact.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A first embodiment of the present invention will now be described with reference to the drawings.
An embodiment will be described. FIG. 1 shows a circuit configuration of a charging stand A and a charging system of a device B to be charged placed on the charging stand A. AC plug 11 for charging stand A
Is supplied to a transformer 12 and is lowered to a predetermined voltage value and then flows to a primary side charging coil L1.

The primary coil of the transformer 12 has a coil L
5 are connected in series, and a diode Di2 is connected to the coil L5.
And a rectifier circuit with a capacitor C2.
The obtained DC voltage is supplied to the charge control circuit 13.

A switch SW1 is provided between the secondary coil of the transformer 12 and the primary charging coil L1 for interrupting the current flowing to the primary charging coil L1, and the switch SW1 is connected to the switch SW1. On / off control is performed by a signal a from the charge control circuit 13.

A charging detection coil L3 is provided separately from the primary charging coil L1, and the charging detection coil L3 is excited by a signal c from the charging control circuit 13.

However, in a state where the device B is placed at a predetermined position on the charging stand A, the secondary-side charging coil L2 is opposed to the primary-side charging coil L1 so that the charging-side detecting coil L3 The charged-side detection coil L4 is provided in the device B so as to be opposed to and is electromagnetically coupled.

The AC power received by the secondary charging coil L2 by electromagnetic induction from the primary charging coil L1 is rectified by the diode Di1 and the capacitor C1, and is supplied to the charging control circuit 14 as a DC power source b. The charged side detection coil L4 is connected in parallel with the capacitor C1.

The charging control circuit 14 charges the secondary battery BT based on the applied DC power supply, and supplies power to other circuit units (not shown). In the circuit configuration as described above, FIG. 2 shows signal waveforms at the above-mentioned respective parts during operation, and a period indicated by I in the figure is a case where the device B is not placed at a predetermined position of the charging stand A. , II, and III show the case where the device B is placed at a predetermined position of the charging stand A, and II shows the initial operation when the device B is placed.

At I in the drawing, while the AC plug 11 is being inserted into the outlet, the coil L5 excites the charge control circuit 13 via the transformer 12 by the obtained AC power supply to operate it. As shown in FIG. 2A, the charge control circuit 13 intermittently supplies a signal a to the switch SW1 with a period T to perform on / off control, thereby controlling the primary side charging coil L1.
Is intermittently excited.

At this time, the device B is located at a predetermined position of the charging stand A.
Is not mounted, the secondary-side charging coil L2 of the device B is not electromagnetically coupled to the primary-side charging coil L1, and even if the primary-side charging coil L1 is intermittently excited, The secondary charging coil L2 cannot receive this, and the DC power supply b is not supplied to the charging control circuit 14 as shown in FIG.

Therefore, the charged side detection coil L4 is not excited, and the signal c in the charged side detection coil L3 not facing the charged side detection coil L4 is also shown in FIG.
As shown in (3), there is no reaction.

However, at the beginning when the device B is placed at a predetermined position of the charging stand A indicated by II in the drawing, the secondary charging coil L2 of the device B is relatively opposed to the primary charging coil L1. 2 (1), when the primary charging coil L1 is intermittently excited as shown in FIG. 2 (1), the secondary charging coil L2 receiving this by electromagnetic induction is shown in FIG. 2 (2). Thus, a DC power supply b to the charge control circuit 14 is generated.

Therefore, the charged side detection coil L4 is also excited, and the signal c of the charged side detection coil L3 opposite to the charged side detection coil L4 becomes as shown in FIG. Thereby, the charge control circuit 13 can recognize that the device B is placed at a predetermined position.

Therefore, in III in the figure, the charge control circuit 13 continuously turns on the switch SW1 by the signal a as shown in FIG. 2A, and continuously turns the primary side charging coil L1 on. Energize. The secondary charging coil L2 receiving the electromagnetic induction generates a continuous DC power supply b to the charge control circuit 14 as shown in FIG. 2 (2). The charging of the secondary battery BT is started.

Thereafter, when the device B is removed from the predetermined position of the charging stand A, the charging-side detecting coil L3 shown in FIG.
Is the same as the case of the above I, so that the charge control circuit 13 can recognize that the device B has been removed from the predetermined position.

As described above, the device B is located at a predetermined position of the charging stand A.
When is not mounted, by intermittently controlling the current flowing through the primary-side charging coil L1, the power consumption in the charging stand A is significantly reduced, and, for example, in the vicinity of the primary-side charging coil L1. Even if there is a metal piece or the like, it is possible to immediately shift to a normal charging operation when the device B is placed at a predetermined position while preventing the heat from being generated.

(Second Embodiment) A second embodiment in which the present invention is applied to a master / charging device using a portable communication terminal as a slave will be described with reference to the drawings.

FIG. 3 shows the circuit configuration. As shown, reference numeral 21 denotes a portable communication terminal as a slave unit, and reference numeral 22 denotes the portable communication terminal 21 as a base unit and a charger. Mobile communication terminal 2
1 has a secondary coil 31 for receiving power when placed at a predetermined position of the base unit / charger 22, and the electric power obtained by the secondary coil 31 is sent to a charging control unit 32. . The charging control unit 32 charges a secondary battery (not shown) with the obtained electric power. The transmission / reception unit 33 is driven by using the secondary battery as a power source, and transmission / reception using the antenna 34 is executed.

The base unit / charger 22 includes a base unit circuit section 35 and a charging circuit section 36. In the base unit circuit section 35, as in the transmission / reception section 33, transmission / reception using an antenna 38 is performed. It has a part 37.

The transmission / reception section 37 transmits and receives data to and from the portable communication terminal 21 as a slave unit as a master unit, and detects the electric field intensity of the portable communication terminal 21 at that time. It is determined whether or not the portable communication terminal 21 is in the vicinity of the predetermined position based on whether or not the threshold value is exceeded, and a signal corresponding to the determination result is transmitted to a charging control unit 42 of the charging circuit unit 36 to be described later. Can be

The charging circuit section 36 includes the portable communication terminal 2
While the primary coil 39 is provided so as to be opposed to the secondary coil 31 when 1 is placed at a predetermined position, a switch for detecting the placement of the mobile communication terminal 21 at the same predetermined position is provided as: For example, a reflection type photo interrupter 4
0 is provided.

The photo-interrupter 40 is composed of an LED and a light-receiving element such as a phototransistor.
The output of the light receiving element is also sent to the switch detector 41. The switch detection unit 41 detects whether or not the portable communication terminal 21 is placed at a predetermined position based on a signal from the light receiving element, and outputs a detection signal to the charge control unit 42.

The charging control unit 42 constantly supplies a DC power obtained by rectifying an AC power from an AC plug (not shown) to the base unit circuit unit 35, and a transmitting / receiving unit of the base unit circuit unit 35. The power supply to the primary coil 39 is controlled by the signal obtained from the switch 37 and the detection signal from the switch detection unit 41, and the portable communication terminal 21 is charged by electromagnetic coupling with the secondary coil 31 as necessary. .

With such a configuration, the contents of determination when the charging control section 42 controls the energization of the primary coil 39 will be described with reference to FIG. That is, the charging control unit 42 first determines whether or not the electric field strength of the mobile communication terminal 21 exceeds the preset threshold value based on the signal obtained from the transmission / reception unit 37, and whether the mobile communication terminal 21 is present near a predetermined position. (Step S1) Only when it is determined that the electric field strength exceeds the threshold value, is it subsequently determined whether or not the mobile communication terminal 21 is correctly placed at a predetermined position based on the detection signal from the switch detection unit 41. (Step S
2).

Then, when it is determined that the portable communication terminal 21 is correctly placed at the predetermined position, power is supplied to the primary coil 39 for a certain period of time for the first time to charge the portable communication terminal 21 (step S3).

However, when the charging for a certain period of time is completed, or when it is determined in step S2 that the portable communication terminal 21 is not correctly placed at a predetermined position, the process returns to step S1 again to return to the portable communication terminal 21. The operation of waiting for the electric field intensity to exceed the threshold value is repeated.

By controlling the charging of the portable communication terminal 21 in accordance with the contents of the medium, the primary coil 39 is energized even though the portable communication terminal 21 is not correctly placed. The device B is moved to a predetermined position while reliably preventing wasteful power consumption and preventing, for example, the generation of heat even when there is a metal piece near the primary coil 39. , The operation can be immediately shifted to the normal charging operation.

Further, the device is mounted at a predetermined position without providing any special configuration such as the coil L4 for detecting the charging side in the first embodiment on the side of the portable communication terminal 21 to be charged. Only when this is done, this can be reliably detected and charging can be performed without contact.

As described above, the reflection type photo interrupter 40 is provided as a switch for detecting whether or not the portable communication terminal 21 is properly placed at a predetermined position of the base unit / charger 22. However, the present invention is not limited to this, and a transmissive photointerrupter 40 or a switch having mechanical contacts may be used in accordance with the shape of the bottom of the portable communication terminal 21 or the like. In addition, the present invention can be variously modified and implemented without departing from the gist thereof.

[0039]

According to the first aspect of the present invention, without providing a terminal or the like for detection on the outer surface of the electronic device to be charged, the device is reliably detected only when the device is mounted. In addition, charging can be performed without contact.

According to the second aspect of the present invention, no special structure such as a detection terminal is provided on the portable communication device to be charged, and the portable communication device can be reliably detected only when the device is mounted. In addition, charging can be performed without contact.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration according to a first embodiment of the present invention.

FIG. 2 is a timing chart for explaining an operation according to the embodiment.

FIG. 3 is a block diagram showing a circuit configuration according to a second embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation according to the embodiment;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... AC plug 12 ... Transformer 13 ... Charge control circuit 14 ... Charge control circuit 21 ... Portable communication terminal (child unit) 22 ... Base unit and charger 31 ... Secondary side coil 32 ... Charge control unit 33 ... Transceiving unit 34 ... Antenna 35 ... Base unit circuit unit 36 ... Charging circuit unit 37 ... Transceiving unit 38 ... Antenna 39 ... Primary side coil 40 ... Photo interrupter 41 ... Switch detection unit 42 ... Charge control unit A ... Charge stand B ... Device BT ... Secondary battery

Claims (2)

[Claims] An electronic device having a built-in secondary battery as a power source is mounted so that power is supplied from the primary charging coil to the secondary charging coil connected to the secondary battery in a non-contact manner. A charging device for charging the secondary battery, wherein the charging device is disposed at a position opposed to a charged detection coil connected in parallel to the secondary charging coil of the electronic device, A charging side detection coil for detecting the presence / absence, a switch for interrupting a current flowing through the primary side charging coil, and detecting the presence / absence of the electronic device based on an output of the charging side detection coil to switch the switch. A charging device, comprising: control means for performing intermittent control. 2. A portable communication device having a built-in secondary battery as a power source is mounted thereon, so that power is supplied from the primary coil to the secondary coil of the secondary battery in a non-contact manner. In a charging device for charging a battery, a presence / absence of the portable communication device is detected by a communication device unit communicating with the portable communication device, and a signal indicating the electric field strength of the portable communication device obtained from the communication device unit. A first detection unit, a second detection unit disposed at a position where the portable communication device is mounted, and detecting presence / absence of the portable communication device; a switch for intermittently flowing a current flowing through the primary coil; Control means for intermittently controlling the switch based on detection results of the first and second detection means.