WO2013015208A1

WO2013015208A1 - Device with built-in battery, and charging station and device with built-in battery

Info

Publication number: WO2013015208A1
Application number: PCT/JP2012/068422
Authority: WO
Inventors: 洋由山本; 真一板垣; 玉井　幹隆
Original assignee: 三洋電機株式会社
Priority date: 2011-07-27
Filing date: 2012-07-20
Publication date: 2013-01-31
Also published as: JP2014195334A

Abstract

[Problem] To normally and fully charge a built-in battery, while accurately transmitting information from a device with the built-in battery to a charging station. [Solution] A device with a built-in battery (50) comprises: a charging switch (54) that supplies the output from a power-receiving coil (51) to the built-in battery (52); a level detector (58) that detects a trace output state whereby the output of the power-receiving coil (51) is smaller than a set value at the charging-start timing, and outputs an output increase signal; a modulation circuit (61) that changes the load for the power-receiving coil (51) and transmits the output increase signal to a charging station (10); and a control circuit (65) that controls the charging switch (54). The charging station (10) comprises an AC power supply (12) and a detection circuit (17) that detects the output increase signal transmitted from the device with the built-in battery (50), and controls the output of the AC power supply (12). When the level detector (58) has a detected trace output state at the charging-start timing, the device with the built-in battery (50) transmits the output increase signal from the device with the built-in battery (50) to the charging station (10), the output of the AC power supply (12) for the charging station (10) is increased, and charging of the built-in battery (52) is started.

Description

Battery built-in device, charging stand and battery built-in device

The present invention relates to a battery built-in device such as a battery pack or a mobile phone, and a charging stand and a battery built-in device for charging electric power to the battery built-in device by electromagnetic induction and charging the built-in battery of the battery built-in device.

A charging stand has been developed that carries power from the transmitting coil to the receiving coil by the action of electromagnetic induction to charge the built-in battery without contact. (See Patent Document 1)

Patent Document 1 describes a structure in which a power transmission coil that is excited by an AC power source is built in a charging stand, and a power receiving coil that is electromagnetically coupled to the power transmission coil is built in a battery pack. Further, the battery pack includes a circuit that rectifies the alternating current induced in the power receiving coil and supplies the battery to the battery for charging. According to this structure, the battery pack can be charged in a non-contact state by placing the battery pack on the charging stand.

Japanese Patent Laid-Open No. 9-63655

As shown in Patent Document 1, a method of electromagnetically coupling a power transmitting coil and a power receiving coil to transmit battery charging power includes a circuit for transmitting information from a battery built-in device to a charging stand. When the built-in battery is fully charged, the fact that the battery built-in device is fully charged is transmitted to the charging stand, and when the battery built-in device is removed from the charging stand, power transmission from the charging stand is stopped or the battery is built-in. This is because a special ID or the like needs to be transmitted from the device to the charging stand and charged normally. The battery built-in device that transmits information to the charging stand includes a modulation circuit that transmits information to the charging stand by changing the load of the power receiving coil.

FIG. 1 shows a battery built-in device 250 including a modulation circuit 266. Modulation circuit 266 shown in this figure changes the load of power receiving coil 251 and transmits information to charging stand 210. The charging stand 210 detects the load fluctuation of the power transmission coil 211 and detects information from the battery built-in device 250. The modulation circuit 266 changes the load on the output side of the power receiving coil 251. When the load of the power reception coil 251 changes, the voltage and frequency of the power transmission coil 211 that supplies AC power from the AC power supply 212 change. Therefore, the charging stand 210 can detect information on the battery built-in device 250 by detecting voltage change or frequency change of the power transmission coil 211.

However, this type of battery-equipped device and charging stand always suffer from a problem that it is difficult to transmit information normally. That is, when the power supplied from the AC power supply to the power transmission coil is small and the output side of the power reception coil is connected to the internal battery via the rectifier circuit, the internal battery with a small internal resistance is connected to the output side of the power reception coil Therefore, the load of the power receiving coil cannot be changed sufficiently with the modulation circuit, and changes in voltage, frequency, etc. of the power transmitting coil cannot be detected accurately. In other words, even if the power induced in the receiving coil is small and a built-in battery with low internal resistance is connected to the receiving coil and modulation is performed to change the load of the receiving coil, the current of the receiving coil cannot be changed greatly. . For this reason, the power transmission coil that is electromagnetically coupled to the power receiving coil has a small change in voltage and frequency, and the fluctuation in the load of the power receiving coil cannot be reliably detected from the power transmission coil side. Since the charging stand detects the load fluctuation of the power receiving coil and detects information from the built-in battery, when the load fluctuation of the power receiving coil is small and the output of the power transmitting coil is small, the voltage and frequency detected by the power transmitting coil The fluctuations of the load such as this will be reduced, and the information on the battery built-in device cannot be detected accurately.

In a state where a large amount of power is transmitted from the charging stand to the battery built-in device, the power induced in the power receiving coil becomes large, so that the information can be transmitted from the battery built-in device to the charging stand by changing the load of the power receiving coil. However, in a system in which electric power is transferred from a charging stand to a battery built-in device by magnetic induction and the built-in battery is charged, a large amount of power is not always supplied to the power transmission coil of the charging stand. In particular, if the power supplied to the power transmission coil is small when the battery built-in device is first set on the charging stand, information from the battery built-in device will not be transmitted to the charging stand, and the charging stand will normally be built in the battery. The device cannot be charged.

Furthermore, when the charging stand is connected to the internal battery with the output side of the power receiving coil connected to the internal battery while the power supplied to the power transmission coil is small, the charging current of the internal battery gradually decreases and hardly flows. . This is because the voltage of the built-in battery rises due to charging, and charging current cannot be supplied from the power receiving coil to the built-in battery. When the charging current stops flowing to the internal battery, it is erroneously determined that the internal battery device has fully charged the internal battery, and charging of the internal battery is stopped. For this reason, although the built-in battery is not fully charged, the charging is completed and it cannot be fully charged.

The present invention was developed for the purpose of solving the above-mentioned drawbacks. An important object of the present invention is to provide a battery built-in device, a charging stand, and a battery built-in device that can normally fully charge the built-in battery while accurately transmitting information from the battery built-in device to the charging stand.

Means for Solving the Problems and Effects of the Invention

The battery built-in device and the charging stand according to the present invention include the battery built-in

devices

50, 70, 80, 90, 100, 110 including the power receiving coil 51 that supplies charging power to the built-in battery 52, and the battery built-in

devices

50, 70, 80. , 90, 100, 110 and charging base 10 including power transmission coil 11 electromagnetically coupled to power reception coil 51. The battery built-in

devices

50, 70, 80, 90, 100, 110 receive power at the charging switch 54 that charges the built-in battery 52 by supplying the output of the power receiving coil 51 to the built-in battery 52 and the charging start timing of the built-in battery 52.

Level detectors

58 and 118 for detecting an output of the coil 51, detecting a minute output state in which the output of the power receiving coil 51 is smaller than a set value, and outputting an output increase signal in the minute output state, and the level detector Control the

modulation circuits

61, 71, 81, 91, 101 that change the load of the power receiving coil 51 and transmit the output increase signal to the charging stand 10, and the charging switch 54 with the output increase signals output from 58, 118.

Control circuits

65 and 115 are provided. The charging stand 10 detects, via the power transmission coil 11, a change in the load of the AC power source 12 that supplies AC power to the power transmission coil 11 and the power receiving coil 51 that is changed by the

modulation circuits

61, 71, 81, 91, 101. In addition, a detection circuit 17 is provided that detects an output increase signal transmitted from the battery built-in

devices

50, 70, 80, 90, 100, and 110, and controls the output of the AC power supply 12 with the detected output increase signal. The battery built-in

devices

50, 70, 80, 90, 100, 110 are in a state where the

level detectors

58, 118 detect a minute output state at the charging start timing of the built-in battery 52, and the battery built-in

devices

50, 70, 80, An output increase signal is transmitted from 90, 100, 110 to the charging stand 10, and the output of the AC power supply 12 of the charging stand 10 is increased to start charging the built-in battery 52.

The battery built-in device and the charging stand described above are characterized in that the internal battery can be normally fully charged while accurately transmitting information from the battery built-in device to the charging stand. When the output of the power receiving coil of the battery built-in device set on the charging stand is small, the battery built-in device outputs an output increase signal to the charging stand, and the charging stand detects the output increase signal. This is because the circuit increases the output of the AC power supply and starts charging the internal battery.

In the battery built-in device and the charging stand according to the present invention, the control circuit 115 includes the level detector 118, and the level detector 118 detects the output of the power receiving coil 51 from the power supplied to the control circuit 115 to detect a minute output state. can do.

In the battery built-in device and the charging stand of the present invention, the detection circuit 17 of the charging stand 10 detects the output increase signal transmitted from the battery built-in

devices

50, 70, 80, 90, 100, 110, and The output can be increased by a preset power.
The above-mentioned battery built-in device and charging stand are in a state where the output of the receiving coil is gradually increased in a predetermined step when the output of the receiving coil is small, and the internal battery is charged when the output of the receiving coil increases to the set value. It becomes. Since the battery built-in device and the charging stand gradually increase the output of the power receiving coil, the built-in battery can be charged with an optimum current.

devices

50, 70, 80, 90, 100, 110, and The output of the AC power supply 12 can be increased by changing the output to a preset power.
When the output increase signal is output from the battery built-in device to the charging stand in the state where the output of the power receiving coil is small, the charging stand supplies the power transmission coil with power that can charge the built-in battery. Therefore, even when the output of the power receiving coil is small, the built-in battery can be quickly switched to a normal charging state and charged.

In the battery built-in device and the charging stand according to the present invention, the built-in battery 52 can be either a lithium ion battery or a lithium polymer battery.

The battery built-in apparatus and the charging stand according to the present invention include a series circuit in which the

modulation circuits

61, 71, 81, 91, and 101 have switching

elements

64, 74, and 84 connected in series to the modulation capacitor 63. A series circuit can be connected in parallel with the power receiving coil 51.

In the battery built-in device and the charging stand of the present invention, the battery built-in device can be a battery pack.

The battery built-in device of the present invention includes a power receiving coil 51 that is electromagnetically coupled to the power transmission coil 11 built in the charging stand 10 and carries power from the power transmission coil 11. The built-in battery 52 is charged by supplying charging power. The battery built-in device supplies the output of the power receiving coil 51 to the built-in battery 52 to charge the built-in battery 52, and detects the output of the power receiving coil 51 at the charging start timing of the built-in battery 52. The

level detectors

58 and 118 for detecting a minute output state in which the output 51 is smaller than the set value and outputting an output increase signal in the minute output state, and the output increase signal output from the

level detectors

58 and 118 Therefore,

modulation circuits

61, 71, 81, 91, 101 that change the load of the power receiving coil 51 and transmit an output increase signal to the charging base 10, and

control circuits

65, 115 that control the charging switch 54 are provided. . The battery built-in device transmits an output increase signal to the charging base 10 when the

level detectors

58 and 118 detect the minute output state at the charging start timing of the internal battery 52, and the output of the AC power supply 12 of the charging base 10 is output. The charging of the built-in battery 52 is started in a state in which increases.

The above battery built-in devices have the feature that the built-in battery can be normally fully charged while accurately transmitting information to the charging stand. This is because, in a minute output state where the output of the power receiving coil is small, an output increase signal is output to the charging stand, and charging of the built-in battery is started in a state where the charging stand increases the output of the AC power supply.

In the battery built-in device of the present invention, the control circuit 115 includes the level detector 118, and the level detector 118 detects the output of the power receiving coil 51 from the power supplied to the control circuit 115 to detect a minute output state. be able to.

The battery built-in device of the present invention can be a battery pack.

It is a schematic block diagram of the conventional battery built-in apparatus and a charging stand. It is a perspective view of the battery built-in apparatus and charging stand concerning one Example of this invention. It is a block diagram of the battery built-in apparatus and charging stand concerning one Example of this invention. It is a block diagram of the battery built-in apparatus concerning the other Example of this invention. It is a block diagram of the battery built-in apparatus concerning the other Example of this invention. It is a graph which shows the relationship between the frequency of the alternating current supplied to a power transmission coil, and the electric current change of a power transmission coil. It is a block diagram of the battery built-in apparatus concerning the other Example of this invention. It is a block diagram of the battery built-in apparatus concerning the other Example of this invention. It is a block diagram of the battery built-in apparatus concerning the other Example of this invention. It is a flowchart in which a battery built-in apparatus charges a built-in battery. It is a flowchart in which a charging stand charges the internal battery of a battery built-in apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment shown below exemplifies a battery built-in device, a charging stand, and a battery built-in device for embodying the technical idea of the present invention, and the present invention includes a battery built-in device, a charging stand, and a battery built-in. The equipment is not specified as follows. Further, this specification does not limit the members shown in the claims to the members of the embodiments.

2 and 3 show a perspective view and a block diagram of the battery built-in device 50 and the charging stand 10. As shown in FIG. 2, the charging stand 10 places the battery built-in device 50 on the charging stand 10 and charges the built-in battery 52 of the battery built-in device 50 by electromagnetic induction. The battery built-in device 50 includes a power receiving coil 51 that is electromagnetically coupled to the power transmitting coil 11. A built-in battery 52 that is charged with electric power induced in the power receiving coil 51 is incorporated. Here, the battery built-in device 50 may be an electronic device such as a mobile phone or an IC player, or may be a pack battery.

The battery built-in device 50 in FIG. 3 detects the output of the power receiving coil 51 at the charging switch 54 for charging the built-in battery 52 by supplying the output of the power receiving coil 51 to the built-in battery 52 and the charging start timing of the built-in battery 52. Thus, a level detector 58 that detects a minute output state in which the output of the power receiving coil 51 is smaller than a set value and outputs an output increase signal in the minute output state, and an output increase signal output from the level detector 58 Accordingly, a modulation circuit 61 that changes the load of the power receiving coil 51 to transmit an output increase signal to the charging base 10 and a control circuit 65 that controls the charging switch 54 are provided. The battery built-in device 50 transmits an output increase signal from the battery built-in device 50 to the charging stand 10 in a state where the level detector 58 detects a minute output state at the charging start timing of the built-in battery 52, and the AC of the charging stand 10 is exchanged. The output of the power supply 12 is increased and charging of the internal battery 52 is started.

The charge switch 54 is a semiconductor switching element such as an FET or a transistor, and is connected between the output side of the rectifier circuit 53 and the built-in battery 52. The charging switch 54 is turned on to charge the built-in battery 52 with the output of the rectifier circuit 53, and stops charging the built-in battery 52 with off-charging.

The level detector 58 detects the output voltage of the power receiving coil 51 and compares it with the lowest voltage stored in advance. The level detector 58 detects the peak voltage of the power receiving coil 51 and compares it with the minimum voltage. The level detector 58 compares the detected output voltage of the power receiving coil 51 with the stored minimum voltage. If the detected voltage is lower than the minimum voltage, the built-in battery 52 cannot be charged with the output of the power receiving coil 51. It is determined that the output is a “micro output state” and an output increase signal is output. The lowest voltage stored in the level detector 58 is set to the lowest output voltage at which the internal battery 52 can be normally charged with the output of the power receiving coil 51. The level detector 58 sets the state in which the output voltage of the power receiving coil 51 is higher than the minimum voltage as a chargeable state and does not output an output increase signal.

3 has a series capacitor 55 connected to the power receiving coil 51, the level detector 58 detects the voltage on the output side of the series capacitor 55, or detects the output voltage of the rectifier circuit 53. Thus, the output voltage of the power receiving coil 51 can also be detected. This is because as the voltage of the power receiving coil 51 increases, the voltage on the output side of the series capacitor 55 increases in proportion to this, and the output voltage of the rectifier circuit 53 also increases in proportion.

The level detector 58 outputs an output increase signal to the control circuit 65 and the modulation circuit 61, controls the charging switch 54 via the control circuit 65, and transmits the output increase signal to the charging stand 10 via the modulation circuit 61. . In a state in which the level detector 58 detects the output increase signal, the control circuit 65 turns off the charging switch 54 to stop the charging of the built-in battery 52, and outputs an output increase signal from the modulation circuit 61 to the charging stand 10. The output of the power transmission coil 11 of the charging stand 10 is increased. However, even when the level detector detects the output increase signal, the control circuit outputs the output increase signal to the charging stand from the modulation circuit while charging the built-in battery without turning off the charging switch. Thus, the output of the power transmission coil of the charging stand can be increased. In a state where the level detector 58 does not output an output increase signal, the control circuit 65 turns on the charging switch 54 to charge the built-in battery 52 with the output of the power transmission coil 11, and the modulation circuit 61 transmits battery information to the charging stand 10. State

The modulation circuit 61 transmits the output increase signal input from the level detector 58 and the battery information of the built-in battery 52 to the charging stand 10. 3 includes a capacitor load circuit 62 in which a switching element 64 is connected in series to a modulation capacitor 63 connected in parallel to the power receiving coil 51, and battery information for detecting battery information of the built-in battery 52. A detection circuit 59 and a control circuit 68 for switching the switching element 64 of the capacitor load circuit 62 on and off by battery information of the battery information detection circuit 59 and an output increase signal input from the level detector 58 are provided.

The battery built-in device 50 includes a battery information detection circuit 59 that detects battery information of the built-in battery 52. With the battery information detection circuit 59, a battery such as a voltage of a charged battery, a charging current, a battery temperature, and the like. Information is detected and input to the control circuit 68.

The control circuit 68 repeats at a predetermined cycle, that is, a transmission timing for transmitting the output increase signal and the battery information and a non-transmission timing at which the output increase signal and the battery information are not transmitted at a predetermined cycle. And transmit battery information. This period is set to, for example, 0.1 sec to 5 sec, preferably 0.1 sec to 1 sec. Since the remaining battery charge, voltage, current, temperature, etc. change, the battery information is repeatedly transmitted in the above-mentioned cycle, but the battery serial number and the battery charge current are allowed to be specified. The battery information such as the charging current and the allowable temperature for controlling the charging of the battery and the output increase signal are transmitted only at the beginning of charging, and need not be transmitted repeatedly thereafter. Further, the battery information of the fully charged battery is transmitted at the timing when the charged battery is fully charged. At the transmission timing, the control circuit 68 transmits the output increase signal and the battery information by switching the switching element 64 on and off with a digital signal indicating the output increase signal and the battery information. For example, the control circuit 68 controls on / off of the switching element 64 at a speed of 1000 bps, and transmits an output increase signal and battery information. However, the control circuit 68 can also transmit an output increase signal and battery information at 500 bps to 5000 bps. After the output increase signal and the battery information are transmitted at 1000 bps at the transmission timing, the transmission of the output increase signal and the battery information is stopped and the built-in battery 52 is charged in a normal state at the non-transmission timing. At the transmission timing, the switching element 64 is switched on and off.

Furthermore, the modulation circuit 71 of the battery built-in device 70 shown in FIG. 4 includes a capacitor load circuit 72 in which a switching element 74 is connected in series to a modulation capacitor 63 connected in parallel with the power receiving coil 51. The switching element 74 in FIG. 4 includes a pair of pair switching elements 74X connected in series with each other. The pair switching element 74X in the figure is a semiconductor switching element such as an FET. The

pair FETs

74a and 74b are connected in series with the sources connected to each other. Further, the source of the FET, which is the connection point of the pair switching element 74X, is connected to the earth line 78 via a high-resistance resistor 79, for example, a 100 kΩ resistor, to have a ground potential. Each pair switching element 74X is connected with a modulation capacitor 63 in series. The

pair FETs

74a and 74b, which are the pair switching elements 74X, are connected to both ends of the power receiving coil 51 via the modulation capacitor 63 connected to the drain. In the switching element 74 of this figure, a capacitor load circuit 72 formed by connecting a modulation capacitor 63, a pair FET 74a, a pair FET 74b, and a modulation capacitor 63 in series is connected in parallel with the power receiving coil 51.

The series capacitor 55 is connected to the rectifier circuit 53 side of the modulation capacitor 63 as shown by a solid line in the figure, or may be connected between the modulation capacitor 63 and the power receiving coil 51 as shown by a chain line. it can. The series capacitor 55 connected between the modulation capacitor 63 and the power receiving coil 51 is connected in series with the modulation capacitor 63 in a state where the pair switching element 74X is switched on.

The

pair FETs

74a and 74b of the pair switching element 74X are switched on and off together by the control circuit 68. The control circuit 68 controls the gate voltages of both FETs that are the pair switching element 74X in the same manner, and switches the pair of pair switching elements 74X on and off simultaneously. The modulation capacitor 63 is connected in parallel with the power receiving coil 51 in a state where the control circuit 68 switches on the FET of the pair switching element 74X. Further, the control circuit 68 turns off the pair switching element 74X, and the modulation capacitor 63 is disconnected from the power receiving coil 51 and is not connected.

The switching element 74 of FIG. 4 can simplify the circuit configuration of the control circuit 68 because one of the pair switching elements 74X is set to the ground potential. In particular, when the rectifier circuit 53 is the diode bridge 53B and both the receiving coils 51 are not at the ground potential, that is, the receiving coil 51 is connected to the earth line 78 via the diode, the control circuit 68 is connected to the pair switching element 74X. It is possible to simplify the circuit configuration for controlling on / off.

5 includes a capacitor load circuit 82 including a capacitor 83 connected to the power receiving coil 51 and a short circuit 88 that shorts the rectifier circuit 53 side of the capacitor 83. I have. The short circuit 88 is a series circuit of a resistance element 89 such as a PTC and a switching element 84. The modulation circuit 81 controls the switching element 84 to be turned on and off and connects the capacitor 83 in parallel with the power receiving coil 51 via the short circuit 88, that is, the capacitor 83 is used in combination with the modulation capacitor 63. The switching element 84 is a photo MOS FET and is turned on / off via light.

The charging stand 10 includes a detection circuit 17 that detects signals transmitted from the

modulation circuits

61, 71, and 81. The detection circuit 17 detects a charging current change or / and voltage change of the built-in battery 52 from a voltage level change or / and current level change of the power transmission coil 11, and outputs an output increase signal from the charging current change or / and voltage change. And battery information. When the charging current or / and voltage of the built-in battery 52 changes, the voltage level and / or current level of the power transmission coil 11 changes because the power transmission coil 11 is electromagnetically coupled to the power reception coil 51. Since the voltage level or / and current level of the power transmission coil 11 change in synchronization with the on / off of the switching

elements

64, 74, 84, the switching

elements

64, 74, 84 can be detected.

Since the

modulation circuits

61, 71, 81 switch the

switching elements

64, 74, 84 on and off with an output increase signal and a digital signal indicating battery information, the detection circuit 17 detects the on / off of the switching

elements

64, 74, 84. Thus, it is possible to detect the output increase signal and the digital signal indicating the battery information, and to detect the output increase signal and the voltage, current, temperature, etc. of the charged battery from the detected digital signal.

However, the detection circuit 17 can also detect an output increase signal and battery information from any one of change values such as a change in the current level of the power transmission coil 11, a phase change with respect to the voltage of the current, or a change in transmission efficiency. This is because these characteristics of the power transmission coil 11 change due to changes in the charging current of the internal battery 52.

By the way, a modulation method in which a modulation capacitor 63 is connected in parallel to the power receiving coil 51 and the

switching elements

64 and 74 are turned on and off to change the impedance of the parallel circuit of the power receiving coil 51 and the modulation capacitor 63 is a modulation method. The resonance frequency of the capacitor 63 and the power receiving coil 51 changes. In this modulation method, as described above, the state in which the current of the power transmission coil 11 changes varies depending on the resonance frequency between the power reception coil 51 and the modulation capacitor 63. FIG. 6 is a graph showing the frequency of the alternating current supplied to the power transmission coil 11 on the X axis and the current change of the power transmission coil 11 on the Y axis. However, in this figure, a curve A indicated by a solid line indicates a state where the resonance frequency of the power receiving coil 51 is 100 kHz, and a curve B indicated by a chain line indicates a state where the resonance frequency of the power receiving coil 51 is 276 kHz. The resonance frequency of the power receiving coil 51 varies depending on the capacitance of a capacitor connected in parallel. Since the capacity of the modulation capacitor 63 is smaller than that of the series resonance capacitor 55, the resonance frequency becomes higher when the modulation capacitor 63 is connected. This is because the resonance frequency is inversely proportional to the square root of the capacitance of the capacitor connected in parallel with the power receiving coil 51.

From this figure, even if the modulation capacitor is connected to the power receiving coil, the switching element is turned on and off, and the resonance frequency is changed from 100 kHz to 276 kHz, the frequency of the power transmission coil at the position where the curve A and the curve B intersect, For example, in the state of about 150 kHz, since the curve A and the curve B overlap, the current of the power transmission coil does not change. If the current of the power transmission coil does not change even when the modulation capacitor is connected, the charging stand cannot detect the output increase signal or the battery information. On the other hand, in the above-described embodiment, such a problem can be eliminated by using the voltage drop changing element as described above.

The

modulation circuits

91 and 101 of the battery built-in

devices

90 and 100 shown in FIG. 7 and FIG. 8 are connected in parallel with a plurality of sets of

capacitor load circuits

62 and 72 each having a modulation capacitor 63 having a different capacitance. is doing. The control circuit 68 of the

modulation circuits

91 and 101 is a capacitor load circuit 62 that can change the current of the power transmission coil 11 by switching the switching

elements

64 and 74 on and off, that is, by changing the resonance frequency of the power reception coil 51. , 72 are controlled to turn on and off, and an output increase signal and battery information are transmitted to the charging base 10. Here, like the switching element 74 shown in FIG. 4 described above, the switching element 74 shown in FIG. 8 includes a pair of pair switching elements 74X connected in series.

The battery built-in

devices

90 and 100 in FIGS. 7 and 8 include a plurality of sets of

capacitor load circuits

62 and 72. Therefore, depending on the frequency of the power transmission coil 11, the modulation capacitor 63 is connected and not connected. The switching

elements

64 and 74 of the

capacitor load circuits

62 and 72 that can change the current of the power transmission coil 11 by connecting and disconnecting the modulation capacitor 63 are turned on and off so that the current of the power transmission coil 11 cannot be changed. Then, an output increase signal and battery information are transmitted. Therefore, the battery built-in

devices

90 and 100 include the modulation capacitors 63 of the plurality of

capacitor load circuits

62 and 72, the resonance frequency of the power receiving coil 51 as the current (or voltage, phase of the current with respect to the voltage, or transmission). By specifying a frequency that can change (efficiency), an output increase signal and battery information can be accurately transmitted to the charging stand 10.

Further, the battery built-in

devices

50, 70, 80, 90, and 100 shown in FIGS. 3 to 5, 7, and 8 store battery information in the charging stand 10 in a state where the built-in battery 52 is charged by the output of the rectifier circuit 53.

Sub-modulation circuits

66, 76 and 86 are also provided for transmission.

The sub-modulation circuit 66 shown in FIGS. 3 and 7 detects battery information of the voltage drop changing element 67 connected between the rectifier circuit 53 that rectifies the output of the power receiving coil 51 and the built-in battery 52, and the battery information of the built-in battery 52. And a control circuit 68 that changes the voltage drop of the voltage drop changing element 67 by a signal from the battery information detection circuit 59.

3 and 7 is a parallel circuit of a diode 67A and a switching element 67B. The diode 67 </ b> A is connected in a direction in which a charging current flows to the internal battery 52, and charges the internal battery 52 with the output of the rectifier circuit 53. The diode 67A generates a predetermined voltage drop with a current flowing in the forward direction. The voltage drop in the forward direction of the diode 67A does not increase in proportion to the current as in the resistor, but is almost constant over a certain current range. Therefore, the output voltage of the rectifier circuit 53 is an added value of the voltage drop of the diode 67A and the voltage of the built-in battery 52. Since the voltage of the built-in battery 52 does not change so much in the normal charging current fluctuation range, the output voltage of the rectifier circuit 53 is increased by the voltage drop of the diode 67, and the charging current flowing in the power receiving coil 51 is reduced. Change the flowing current.

The switching element 67B is an element having a low on-resistance in the on state, for example, a semiconductor switching element such as an FET or a transistor. The switching element 67B having a small on-resistance short-circuits both ends of the diode 67A in the on state so that the voltage drop across the diode is almost 0V. Therefore, in the ON state of the switching element 67B, the output voltage of the rectifier circuit 53 is supplied to the built-in battery 52 without voltage drop by the diode 67A, and in the OFF state of the switching element 67B, the output voltage of the rectifier circuit 53 is the diode 67A. The voltage is dropped and supplied to the internal battery 52. The charging current of the built-in battery 52 charged with a voltage drop at the diode 67A is smaller than the charging current charged without a voltage drop at the diode 67A. That is, the charging current of the built-in battery 52 can be changed by controlling the switching element 67B to be on / off.

Since the charging current of the internal battery 52 is supplied from the power receiving coil 51, when the charging current of the internal battery 52 changes, the load of the power receiving coil 51 changes. When the load of the power receiving coil 51 changes, the current, voltage, phase, and the like of the power transmission coil 11 change, so that the charging stand 10 can detect these changes in the power transmission coil 11 and detect the on / off state of the switching element 67B. Therefore, the battery built-in device 50 can modulate the switching element 67B to be turned on / off with the output increase signal or the battery information, and transmit the output increase signal or the battery information to the charging stand 10.

The switching element 67B is controlled on and off by the control circuit 68. The control circuit 68 switches the switching element 67B on and off with the output increase signal and the battery information, and transmits the output increase signal and the battery information to the charging stand 10. The control circuit 68 transmits an output increase signal and battery information as a digital signal. The battery information controls the full charge, remaining capacity, voltage, charging current, battery temperature, battery serial number, allowable charging current that identifies the battery charging current, and battery charging. Allowable temperature to be used. The battery information and the output increase signal are transmitted as a digital signal by controlling the switching element 67B.

At the transmission timing, the control circuit 68 switches the switching element 67B on and off with a digital signal indicating an output increase signal or battery information, changes the voltage drop of the voltage drop change element 67, that is, modulates the output increase signal. And transmit battery information. For example, the control circuit 68 controls on / off of the switching element 67B at a speed of 1000 bps and transmits an output increase signal and battery information. However, the control circuit 68 can also transmit an output increase signal and battery information at 500 bps to 5000 bps. After the output increase signal and the battery information are transmitted at 1000 bps at the transmission timing, the transmission of the output increase signal and the battery information is stopped and the built-in battery 52 is charged in a normal state at the non-transmission timing. At the transmission timing, the switching element 67B is switched on and off.

The control circuit 68 holds the switching element 67B in the ON state at the non-transmission timing, and short-circuits both ends of the diode 67A. In this state, the output of the rectifier circuit 53 is directly supplied to the built-in battery 52 for charging. This method can efficiently charge the internal battery 52 at the non-transmission timing. However, the switching element can be kept off at the non-transmission timing.

The charging stand 10 detects the load fluctuation of the power receiving coil 51 from the voltage level change or / and the current level change of the power transmission coil 11 by the detection circuit 17, and detects an output increase signal and battery information. The sub-modulation circuit 66 shown in FIGS. 3 and 7 changes the load of the power receiving coil 51 by changing the charging current or / and voltage of the internal battery 52. When the charging current or / and voltage of the power receiving coil 51 is changed, the power transmission coil 11 is electromagnetically coupled to the power receiving coil 51, so that the voltage level and / or current level of the power transmission coil 11 is changed. Since the voltage level and / or current level of the power transmission coil 11 changes in synchronization with the on / off state of the switching element 67B, the on / off state of the switching element 67B can be detected from the change in the voltage level or / and current level of the power transmission coil 11. Since the control circuit 68 switches the switching element 67B on and off with a digital signal indicating an output increase signal and battery information, the detection circuit 17 indicates the output increase signal and battery information when the switching circuit 67B is detected on and off. A digital signal can be detected, and an output increase signal, full charge, remaining capacity, voltage, current, temperature, and the like of a charged battery can be detected from the detected digital signal.

However, the detection circuit 17 detects an output increase signal and battery information from any one of change values such as a change in the current level of the power transmission coil 11, a change in the voltage level, a phase change with respect to the voltage of the current, or a change in transmission efficiency. You can also This is because these characteristics of the power transmission coil 11 change due to changes in the charging current of the internal battery 52.

3 and 7, the sub modulation circuit 66 of the battery built-in

devices

50 and 90 has a voltage drop changing element 67 as a parallel circuit of a diode 67A and a switching element 67B. In the sub-modulation circuit 76 of the battery built-in

devices

70 and 100 shown in FIGS. 4 and 8, the voltage drop changing element 77 is an FET 77B having a parasitic diode 77A. The FET 77B having the parasitic diode 77A is a circuit substantially equivalent to the voltage drop changing element 67 of FIGS. 3 and 7 in which the switching element 67B is connected in parallel with the diode 67A. Therefore, the battery built-in

devices

70 and 100 control the FET 77B, which is the switching element of the voltage drop changing element 77, to be turned on and off, and in the same way as the battery built-in

devices

50 and 90 in FIGS. Battery information can be transmitted to the charging stand 10.

In this voltage drop changing element 77, the forward direction of the parasitic diode 77A is a direction in which a current for charging the built-in battery 52 flows. The voltage drop changing element 77 controls the FET 77B to be turned on / off by the control circuit 68, and changes the charging current of the built-in battery 52. With the FET 77B turned off, the built-in battery 52 is charged via the parasitic diode 77A. Therefore, a voltage drop occurs at both ends of the parasitic diode 77A, the output voltage of the rectifier circuit 53 is increased by the voltage drop of the parasitic diode 77A, and the charging current flowing through the power receiving coil 51 is lowered. When the FET 77B is on, the voltage drop of the parasitic diode 77A is almost 0V, the output voltage of the rectifier circuit 53 is almost the same voltage as the built-in battery 52, and the charging current flowing through the power receiving coil 51 is increased.

Furthermore, the sub modulation circuit 86 of the battery built-in device 80 shown in FIG. 5 implements the voltage drop changing element 87 by a semiconductor switching element such as an FET or a transistor without a parasitic diode. The voltage drop changing element 87 in the figure is an FET 87B, and this FET 87B is used in combination with the charge switch 54. The voltage drop changing element 87 changes the on-resistance and transmits an output increase signal and battery information to the charging base 10. The voltage drop changing element 87 controls the charging current or / and voltage of the built-in battery 52 by changing the on-resistance to approximately 0Ω and a low resistance state that is not 0Ω. The on-resistance of the voltage drop changing element 87 is controlled by a signal input from the control circuit 68 to the gate and base. The voltage drop changing element 87 of the FET 87B changes the on-resistance with a signal input from the control circuit 68 to the gate. The voltage drop changing element of the transistor changes the on-resistance with a current input from the control circuit to the base. The voltage drop changing element 87 also controls the on-resistance of the semiconductor switching element to be small at the non-transmission timing, and efficiently charges the internal battery 52 with the output of the rectifier circuit 53.

Furthermore, although the voltage drop changing element is not shown, it can also be realized by a parallel circuit of a resistor and a switching element. This voltage drop changing element is a switching element that short-circuits both ends of the resistor to reduce the voltage drop to almost 0V, and the switching element is turned off to increase the voltage drop of the resistor, thereby changing the charging current of the built-in battery, An output increase signal and battery information are transmitted to the charging stand.

The

sub charging circuits

66, 76, 86 described above can transmit battery information to the charging base 10 when the control circuit 65 switches on the charging switch 54 and charges the built-in battery 52. However, these sub-modulation circuits also transmit an output increase signal to the charging stand at the charging start timing when the battery built-in device is set on the charging stand and battery information such as ID information is transmitted from the battery built-in device to the charging stand. You can also

These battery built-in

devices

50, 70, 80, 90, and 100 provide the charging base 10 with an output increase signal and battery information in both the

sub-modulation circuits

66, 76, and 86 and the

modulation circuits

61, 71, 81, 91, and 101. By transmitting, an output increase signal and battery information are transmitted to the charging stand 10 more reliably. The battery built-in

devices

50, 70, 80, 90, 100 are

sub-modulation circuits

66, 76, 86 and

modulation circuits

61, 71, 81, 91, 101. 10 is transmitted. The battery built-in

devices

50, 70, 80, 90, 100 that transmit the output increase signal and the battery information in a time division manner with the

sub modulation circuits

66, 76, 86 and the

modulation circuits

61, 71, 81, 91, 101 are sub modulation At the end of transmitting the output increase signal or battery information in the

circuits

66, 76, 86, a switching signal for switching to the

modulation circuits

61, 71, 81, 91, 101 is output, and the

modulation circuits

61, 71, 81, 91, 101 are output. Finally, the switching signal for switching to the

sub-modulation circuits

66, 76, 86 is output at the end of transmitting the output increase signal and the battery information. The charging stand 10 detects the switching signal and detects an output increase signal and battery information from the signals of the

sub modulation circuits

66, 76, 86 and the

modulation circuits

61, 71, 81, 91, 101. Also, the battery built-in

devices

50, 70, 80, 90, 100 that transmit the output increase signal and the battery information in both the

sub modulation circuits

66, 76, 86 and the

modulation circuits

61, 71, 81, 91, 101 in time division are The

sub modulation circuits

66, 76, 86 and the

modulation circuits

61, 71, 81, 91, 101, for example, output increase signals and battery information as different signals such as different transmission speeds between 500 bps and 5000 bps. Thus, the charging base 10 can distinguish between the signals of the

sub-modulation circuits

66, 76, 86 and the signals of the

modulation circuits

61, 71, 81, 91, 101.

However, the battery built-in device can transmit the output increase signal and the battery information to the charging stand only by the modulation circuit, or can transmit the output increase signal and the battery information to the charging stand only by the sub modulation circuit. When the sub-modulation circuit fails, the modulation circuit transmits an output increase signal and battery information to the charging stand. When the modulation circuit fails, the sub-modulation circuit transmits an output increase signal and battery information to the charging stand. You can also

In the battery built-in

devices

50, 70, 80, 90, 100 described above, the control circuit 68 includes the switching

elements

64, 74, 84 of the

modulation circuits

61, 71, 81 and the voltage drop change elements of the

sub modulation circuits

66, 76, 86. 67, 77 and 87 are controlled. The control circuit 68 switches the switching

elements

64, 74, and 84 on and off with an output increase signal and battery information, and transmits the output increase signal and battery information to the charging stand 10. The control circuit 68 controls the switching

elements

64, 74, and 84 to transmit the output increase signal and the battery information as digital signals.

The control circuit 68 repeats at a predetermined cycle, that is, a transmission timing for transmitting the output increase signal and the battery information and a non-transmission timing at which the output increase signal and the battery information are not transmitted at a predetermined cycle. And transmit battery information. However, since the control circuit 68 also controls the

sub modulation circuits

66, 76, 86, the voltage

drop changing elements

67, 77, 87 of the

sub modulation circuits

66, 76, 86 and the switching element 64 of the

modulation circuits

61, 71, 81, 74 and 84 are controlled in a time-sharing manner. At the transmission timing, the

modulation circuits

61, 71, 81 switch the

switching elements

64, 74, 84 on and off with a digital signal indicating an output increase signal or battery information, and modulate and output the parallel capacitance of the power receiving coil 51. Transmit increase signal and battery information. For example, the control circuit 68 performs on / off control of the switching

elements

64, 74, and 84 at a speed of 1000 bps, and transmits an output increase signal and battery information. However, the control circuit 68 can also transmit an output increase signal and battery information at 500 bps to 5000 bps. After the output increase signal and battery information are transmitted at 1000 bps at the transmission timing, the transmission of the output increase signal and battery information is stopped and the battery is charged in a normal state at the non-transmission timing. At the transmission timing, the switching

elements

64, 74, and 84 are switched on and off. A modulation capacitor 63 is connected to the power receiving coil 51 in order to transmit an output increase signal and battery information. Since the modulation capacitor 63 is connected in parallel to the power reception coil 51, the efficiency of power transfer from the power transmission coil 11 to the power reception coil 51 is slightly reduced from the designed optimum state. However, the transmission timing is shorter than the non-transmission timing, and the timing at which the modulation capacitor 63 is connected to the power receiving coil 51 is very short even at this transmission timing. Even if the power transfer efficiency is reduced in a state where the power is connected, the reduction in power transfer efficiency can be almost negligible in the total time.

Further, the battery built-in

devices

50, 70, 80, 90, 100 shown in FIGS. 3 to 5, 7, and 8 are connected to the power receiving coil 51 and convert alternating current induced in the power receiving coil 51 into direct current. A rectifier circuit 53 that supplies charging power to the built-in battery 52 is provided. The rectifier circuit 53 converts the alternating current input from the power receiving coil 51 into direct current, and charges the internal battery 52. The rectifier circuit 53 in FIGS. 3, 5, and 7 is a synchronous rectifier circuit 53A. The synchronous rectifier circuit 53A includes four FETs 53a connected to the bridge, and a switching circuit 53b that controls on / off of each FET 53a. The switching circuit 53b switches the FET 53a in synchronization with the alternating current output from the power receiving coil 51, converts the input alternating current to direct current, and outputs the direct current. Since the voltage drop of the FET 53a is smaller than that of the diode, the synchronous rectifier circuit 53A has a feature that it can rectify more efficiently than a diode bridge and reduce power loss due to the voltage drop. However, it goes without saying that a diode bridge 53B can be used for the rectifier circuit 53 in place of the synchronous rectifier circuit as shown in FIGS.

A charging switch 54 that is connected between the output side of the rectifier circuit 53 and the built-in battery 52 and controls charging of the built-in battery 52 is controlled to be turned on and off by a control circuit 65. The control circuit 65 controls the charging switch 54 to be turned on / off by a signal from the level detector 58 and a signal from the battery information detection circuit 59. The control circuit 65 controls the charging switch 54 to be turned on in a state where the level detector 58 does not output an output increase signal, that is, in a state where the output of the power receiving coil 51 is larger than the set value and is not in a minute output state. 52 is charged. Further, the control circuit 65 detects whether or not the built-in battery 52 is in a chargeable state by a signal from the battery information detection circuit 59. If the built-in battery 52 is in a chargeable state, the control circuit 65 turns on the charge switch 54 and incorporates it. The battery 52 is charged. That is, the control circuit 65 turns on the charging switch 54 with no output increase signal input from the level detector 58 and a signal indicating that the built-in battery 52 can be charged from the battery information detection circuit 59. The built-in battery 52 is charged as follows. When the built-in battery 52 is fully charged or the battery temperature becomes high, the control circuit 65 switches the charging switch 54 to OFF and stops charging the built-in battery 52.

The battery built-in

devices

50, 70, 80, 90, 100 described above are stored in advance by connecting the level detector 58 to the output side of the power receiving coil 51 and directly detecting the output voltage of the power receiving coil 51. It is detected whether or not the output voltage is very small compared to the lowest voltage. However, the level detector can also detect the output voltage of the power receiving coil 51 by detecting the output voltage of the rectifier circuit 53 as shown in FIG. 9 without detecting the output voltage of the power receiving coil. The battery built-in device in FIG. 9 has a function of a level detector 118 provided to a control circuit 115 having a microcomputer built therein, and the level detector 118 detects the output of the power receiving coil 51. This control circuit 115 has an input line 119 connected to the output side of the rectifier circuit 53 as an operating power source, and the level detector 118 detects the output of the receiving coil 51 from the operating power supplied to the control circuit 115. Yes. According to this circuit configuration, the voltage or / and the current after rectification (current consumed or used in the control circuit 115) supplied to the control circuit 115 in a state where the charging switch 54 is turned off at the charging start timing. It can be detected and compared with the set value, and it can be determined whether or not it is a minute output state. Although not shown, the level detector 118 detects, for example, a current flowing through the current detection resistor by connecting a Zener diode, through which a current flows when the applied voltage exceeds a threshold, to a control circuit, which is a microcomputer, for protection. Thus, the rectified voltage or / and current supplied to the control circuit 115 can be detected even when the charging switch 54 is turned off. Even without such a Zener diode, the current consumption of the control circuit can be detected by a current detection resistor. The level detector 118 detects, for example, the rectified voltage and current supplied to the control circuit 115, obtains supply power from these products, compares the supply power with a predetermined value, and is below a predetermined value. If so, the modulation circuit 61 is operated by the control circuit 115 so as to output an output increase signal in a minute output state. However, the level detector detects the rectified voltage supplied to the control circuit, compares this voltage with the lowest voltage stored in advance, and the detected voltage is lower than the lowest voltage that is the set value. It is also possible to output an output increase signal by determining that the output state is minute. Further, the level detector detects the current after rectification supplied to the control circuit, and compares this current with the minimum current stored in advance, and the detected current is lower than the minimum current that is the set value. It is also possible to output an output increase signal by determining that the output state is minute. Further, the control circuit 115 turns on the charging switch 54 as a chargeable state without outputting an output increase signal when the supply power or the output voltage or current from the rectifier circuit 53 to the control circuit 115 is larger than the set value. Switching is started and charging of the internal battery 52 is started.

2 and 3 detects and detects a power transmission coil 11, an AC power supply 12 that supplies AC power to the power transmission coil 11, and an output increase signal transmitted from the battery built-in device 50. A detection circuit 17 for controlling the output of the AC power supply 12 by an output increase signal is provided. The detection circuit 17 detects a change in the load of the power receiving coil 51 that is changed by the modulation circuit 61 of the battery built-in device 50 via the power transmission coil 11 to detect an output increase signal.

The charging stand 10 in FIG. 2 charges the internal battery 52 by placing the battery internal device 50 on the top plate 21 of the casing 20. In order to efficiently charge the internal battery 52, the charging stand 10 includes a mechanism for bringing the power transmission coil 11 close to the power reception coil 51 of the battery built-in device 50 (not shown). The charging stand 10 includes a mechanism (not shown) that detects the position of the power receiving coil 51 and causes the power transmitting coil 11 to approach the power receiving coil 51. The charging stand 10 detects the positions of the power receiving coil 51 placed on the top plate 21 in the X-axis direction and the Y-axis direction, and moves the power transmitting coil 11 to the detected position. Since the charging stand 10 can bring the power transmission coil 11 close to the power receiving coil 51, it can efficiently carry power from the power transmitting coil 11 to the power receiving coil 51. However, the battery built-in device and the charging stand according to the present invention make the power receiving coil approach the power transmitting coil by setting the battery built-in device at a specific position on the charging stand without moving the power transmitting coil to the position of the power receiving coil. Thus, the electromagnetic coupling can be achieved. By enlarging the power transmission coil and placing the power reception coil inside the large power transmission coil, the battery built-in device can be set on the charging stand so that the power transmission coil and the power reception coil can be electromagnetically coupled. Therefore, this invention does not specify a charging stand as what moves a power transmission coil to the position of a receiving coil, and makes it approach.

The power transmission coil 11 is wound in a spiral shape on a surface parallel to the upper surface plate 21 and radiates an alternating magnetic flux above the upper surface plate 21. The power transmission coil 11 radiates an alternating magnetic flux orthogonal to the upper surface plate 21 above the upper surface plate 21. The power transmission coil 11 is supplied with AC power from the AC power source 12 and radiates AC magnetic flux above the upper surface plate 21.

The AC power supply 12 supplies, for example, high frequency power of 20 kHz to several MHz to the power transmission coil 11. As shown in FIG. 3, the AC power supply 12 is controlled by the detection circuit 17 to control AC power output to the power transmission coil 11. When an output increase signal is input from the detection circuit 17, the AC power supply 12 increases the AC power output to the power transmission coil 11. When an output increase signal is input from the detection circuit 17, the AC power supply 12 increases the output at a preset rate or increases the output to a preset power. For example, the AC power supply 12 that can change the AC power to 0.1 W, 0.5 W, 1 W, 3 W, and 5 W can be changed from 0.1 W to 0.5 W and 0.5 W each time an output increase signal is input. The output is increased from 1 W to 1 W, from 3 W to 5 W, or when an output increase signal is input, the output is increased to 3 W or 5 W set in advance. The AC power supply 12 can also increase the output by a preset ratio, for example, 10% to 50% each time an output increase signal is input.

The charging stand 10 supplies AC power from the AC power source 12 to the power transmission coil 11 in a state where the battery built-in device 50 is set. The charging stand 10 detects that the battery built-in device 50 has been set by a user pressing a set switch (not shown), and supplies AC power from the AC power supply 12 to the power transmission coil 11 or the battery built-in device. The fact that 50 is set is detected electrically or with a limit switch or the like, and power is supplied from the AC power supply 12 to the power transmission coil 11. The charging stand 10 that electrically detects that the battery built-in device 50 is set outputs a pulse signal for detection from the power transmission coil 11 and detects an echo signal of the detection pulse signal from the power reception coil 51, or It can be detected that the battery built-in device 50 is set by a change in inductance or impedance of the power transmission coil 11.

The battery built-in device 50 and the charging stand 10 described above charge the built-in battery 52 as follows.
(1) The charging stand 10 detects whether or not the battery built-in device 50 is set.
(2) When the charging stand 10 detects that the battery built-in device 50 is set, the AC power supply 12 outputs AC power to the power transmission coil 11.
(3) Battery information such as battery ID, voltage, and temperature is transmitted from the battery built-in device 50 to the charging stand 10 at the charging start timing.
(4) The battery built-in device 50 detects the output voltage of the AC signal induced in the power receiving coil 51 with the level detector 58.
When the level detector 58 detects that the output voltage of the power receiving coil 51 is larger than the set value and confirms that the internal battery 52 can be charged from the battery information, the control circuit 65 turns on the charging switch 54. Switching is started and charging of the internal battery 52 is started, and when the internal battery 52 is fully charged, the charging switch 54 is switched off to end the charging.
When the voltage induced in the power receiving coil 51 is smaller than the set value, the level detector 58 determines that the output state is minute, outputs an output increase signal to the control circuit 65 and the sub modulation circuit 66, and the control circuit 65 is charged. The switch 54 is kept off, and the built-in battery 52 is not charged.
(5) The sub modulation circuit 66 changes the load of the power receiving coil 51 with the output increase signal input from the level detector 58 and transmits the output increase signal to the charging stand 10.
(6) The charging stand 10 detects an output increase signal with a detection circuit 17 that detects a change in voltage or frequency of the power transmission coil 11, and the AC power supply 12 supplies the power transmission coil 11 with the output increase signal. Increase AC power.
(7) When the output of the power transmission coil 11 is increased, this is detected by the level detector 58 of the battery built-in device 50. When the level detector 58 detects the output voltage of the power receiving coil 51 and this detected voltage is larger than the set value, the charging start timing is terminated, the charging switch 54 is turned on, and the charging of the built-in battery 52 is started. To do.
(8) Even if an output increase signal is transmitted from the battery built-in device 50 to the charging stand 10, if the output voltage of the power receiving coil 51 is lower than the set value, the output of the power receiving coil 51 is not terminated without completing the charging start timing Until the voltage exceeds the set value, the battery built-in device 50 outputs an output increase signal. When the output voltage of the power receiving coil 51 exceeds the set value, the charging start timing is terminated and the built-in battery 52 starts charging.
(9) When the built-in battery 52 is fully charged, this is transmitted from the battery built-in device 50 to the charging stand 10, and the charging stand 10 cuts off the output of AC power from the AC power supply 12 to the power transmission coil 11. Then, the charging of the internal battery 52 is terminated.

The battery built-in device 50 and the charging stand 10 as described above charge the built-in battery 52 in the following steps as shown in FIG.
[Battery built-in device 50]
[Step of n = 1]
It is detected whether or not the battery built-in device 50 is set on the charging stand 10. The battery built-in device 50 detects the pulse signal output from the charging stand 10 and detects that it is set on the charging stand 10.
[Step of n = 2]
When the battery built-in device 50 is set on the charging stand 10, the battery information is transmitted to the charging stand 10 by the sub modulation circuit 66.
[Steps n = 3, 4]
The level detector 58 detects the output voltage of the power receiving coil 51 and compares the detected voltage with a set value.
[Step n = 5]
When the detection voltage detected by the level detector 58 is equal to or lower than the set value, the sub modulation circuit 66 outputs an output increase signal.
The steps of n = 3 to 5 are looped until the output voltage of the power receiving coil 51 exceeds the set value.
[Step n = 6]
When the output voltage of the power receiving coil 51 is larger than the set value, the control circuit 65 switches on the charging switch 54 in this step and starts charging the built-in battery 52.
[Steps of n = 7, 8]
Charging is performed until the internal battery 52 is fully charged. When the built-in battery 52 is fully charged, the charging switch 54 is turned off to end charging.

[Charging stand 10]
As shown in FIG. 11, the charging stand 10 outputs AC power to the battery built-in device 50 in the following steps.
[Steps of n = 1, 2]
When the battery built-in device 50 is detected and the battery built-in device 50 is set, the AC power source 12 outputs AC power to the power transmission coil 11.
[Step n = 3]
The detection circuit 17 determines whether or not an output increase signal is transmitted from the battery built-in device 50.
[Step n = 4]
When an output increase signal is detected, an output increase signal is output to the AC power source 12, the AC power source 12 increases the AC power output to the power transmission coil 11, and if no output increase signal is detected, the output of the AC power source 12 is changed. I will not let you.
[Steps n = 5, 6]
When the detection circuit 17 detects that the built-in battery 52 is fully charged, the AC power supply 12 stops the output of AC power to the power transmission coil 11 and ends the charging.

DESCRIPTION OF SYMBOLS 10 ... Charging stand 11 ... Power transmission coil 12 ... AC power supply 17 ... Detection circuit 20 ... Casing 21 ... Top plate 50 ... Battery built-in apparatus 51 ... Power receiving coil 52 ... Built-in battery 53 ... Rectification circuit 53A ... Synchronous rectification circuit 53a ... FET
53b ... Switching circuit 53B ... Diode bridge 54 ... Charge switch 55 ... Series capacitor 58 ... Level detector 59 ... Battery information detection circuit 61 ... Modulation circuit 62 ... Capacitor load circuit 63 ... Modulation capacitor 64 ... Switching element 65 ... Control circuit 66 ... Sub modulation circuit 67 ... Voltage drop changing element 67A ... Diode 67B ... Switching element 68 ... Control circuit 70 ... Battery built-in equipment 71 ... Modulation circuit 72 ... Condenser load circuit 74 ... Switching element 74X ... Pair switching element 74a ... Pair FET
74b ... Pair FET
76 ... Submodulation circuit 77 ... Voltage drop changing element 77A ... parasitic diode 77B ... FET
78 ... Earth line 79 ... Resistor 80 ... Built-in battery device 81 ... Modulation circuit 82 ... Capacitor load circuit 83 ... Capacitor 84 ... Switching element 86 ... Sub modulation circuit 87 ... Voltage drop change element 87B ... FET
DESCRIPTION OF SYMBOLS 88 ... Short circuit 89 ... Resistance element 90 ... Battery built-in apparatus 91 ... Modulation circuit 100 ... Battery built-in apparatus 101 ... Modulation circuit 110 ... Battery built-in apparatus 115 ... Control circuit 118 ... Level detector 119 ... Input line 210 ... Charging stand 211 ... Power transmission coil 212 ... AC power supply 250 ... Battery built-in device 251, Power receiving coil 266 ... Sub modulation circuit

Claims

A battery built-in device including a power receiving coil for supplying charging power to the built-in battery;
It consists of a charging stand with a power transmission coil that is electromagnetically coupled to the power reception coil of this battery built-in device,
The battery built-in device detects the output of the power receiving coil at a charging start timing of charging the built-in battery by supplying the power of the power receiving coil to the built-in battery, and the output of the power receiving coil is A level detector that detects a minute output state smaller than the set value and outputs an output increase signal in the minute output state, and an output increase signal output from this level detector, changes the load of the receiving coil. A modulation circuit that transmits an output increase signal to the charging stand, and a control circuit that controls the charging switch;
The charging stand is an AC power supply for supplying AC power to the power transmission coil, and an output increase signal transmitted from the battery built-in device by detecting a change in the load of the power receiving coil changed by the modulation circuit via the power transmission coil. And a detection circuit that controls the output of the AC power supply with an output increase signal to be detected,
In the battery built-in device, an output increase signal is transmitted from the battery built-in device to the charging stand in a state where the level detector detects a minute output state at the charging start timing of the built-in battery, and the output of the AC power supply of the charging stand is A battery built-in device and a charging stand that are configured to start charging the built-in battery.
The battery according to claim 1, wherein the control circuit includes a level detector, and the level detector detects an output of the power receiving coil from electric power supplied to the control circuit to detect a minute output state. Built-in equipment and charging stand.
The battery built-in device according to claim 1 or 2, wherein the detection circuit of the charging stand detects an output increase signal transmitted from the battery built-in device and increases the output of the AC power source by a preset power. And charging stand.
The detection circuit of the charging stand detects an output increase signal transmitted from the battery built-in device, changes the output of the AC power supply to a preset set power, and increases the output of the AC power supply. The battery built-in apparatus and charging stand described in any one of 1 thru | or 3.
The battery built-in device and the charging stand according to any one of claims 1 to 4, wherein the built-in battery is either a lithium ion battery or a lithium polymer battery.
The said modulation circuit is provided with the series circuit which connected the switching element to the modulation capacitor in series, and this series circuit is connected in parallel with the said receiving coil, It is described in any one of Claim 1 thru | or 5 Battery built-in equipment and charging stand.
The battery built-in device and the charging stand according to any one of claims 1 to 6, wherein the battery built-in device is a battery pack.
A battery comprising a power receiving coil that is electromagnetically coupled to a power transmission coil built in a charging stand and that carries power from the power transmission coil, and that charges the built-in battery by supplying charging power from the power receiving coil to the internal battery. A built-in device,
A charging switch that supplies the output of the power receiving coil to the internal battery to charge the internal battery, and at the charging start timing of the internal battery, the output of the power receiving coil is detected, and the output of the power receiving coil is smaller than a set value A level detector that detects a minute output state and outputs an output increase signal in the minute output state, and an output increase signal output from this level detector changes the load of the power receiving coil to charge the output increase signal A modulation circuit for transmitting to a table, and a control circuit for controlling the charging switch,
When the level detector detects a minute output state at the charging start timing of the built-in battery, an output increase signal is transmitted to the charging stand, and charging of the built-in battery starts when the output of the AC power supply of the charging stand increases. A battery built-in device.
The battery according to claim 8, wherein the control circuit includes a level detector, and the level detector detects an output of the power receiving coil from power supplied to the control circuit to detect a minute output state. Built-in equipment.
The battery built-in device according to claim 8 or 9, wherein the battery built-in device is a battery pack.