Induction type power supply device

An induction type power supply device includes a power supply base unit having a connection interface connectable, an oscillator circuit for producing an AC signal upon connection of the connection interface to an electric outlet, a driver circuit for amplifying the AC signal and a primary inductor for obtaining a resonant frequency and releasing the AC signal, and an attached induction device placed on the power supply base unit and having a secondary inductor for receiving the AC signal from the primary inductor by means of magnetic induction, a rectifier filter circuit for converting the AC signal into a DC power supply, a power management circuit for regulating the DC power supply subject to a predetermined voltage and current value and a connection device for the connection of an external mobile electronic apparatus and for outputting the regulated DC power supply from the power management circuit to the connected external mobile electronic apparatus.

This application claims the priority benefit of Taiwan patent application number 097207329 filed on Apr. 28, 2008.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to power supply devices and more particularly an induction type power supply device, which comprises a power supply base unit connectable to an electric outlet to obtain an AC power supply, and an attached induction device placed on the power supply base unit for receiving the AC power supply from the power supply base unit by means of magnetic induction and converting the AC power supply into the desired DC power supply for output to an external mobile electronic apparatus being connected thereto.

2. Description of the Related Art

With the coming of digital era, many digitalized electronic products, such as digital camera, cellular telephone, music player (MP3) etc., have been continuously developed and have appeared on the market. These modern digital electronic products commonly have light, thin, short and small characteristics. For high mobility, power supply is an important factor. A mobile digital electronic product generally uses a rechargeable battery to provide the necessary working voltage. When power low, the rechargeable battery can be recharged. For charging the rechargeable battery of a digital electronic product, a battery charger shall be used. However, it is not economic to purchase a respective battery charger when buying a new mobile electronic product.

Further, when using a battery charger to charge the rechargeable battery of a mobile electronic product, it is necessary to connect the connection interface of the battery charger to an electric outlet and then insert the power output plug of the battery charger to the power jack of the mobile electronic product. After charging, the user needs to remove the battery charger from the mobile electronic product. When wishing to charge the rechargeable battery of a mobile electronic product, the user must carry the mobile electronic product to a place where there is an electric outlet. When one goes out and there is no any electric outlet available, the user will be unable to charge the rechargeable battery of his(her) mobile electronic product.

The use of a conventional battery charger has the drawbacks as follows:

1. When using many different mobile electronic products, one shall have to prepare many different battery chargers for charging the mobile electronic products separately. It costs a lot to prepare many different battery chargers.

2. A conventional battery charger can be used to charge a mobile electronic product only where there is an electric outlet. When one goes out to a place where there is no any electric outlet and the power of the rechargeable battery of his(her) mobile electronic product is low, he(she) will be unable to charge the mobile electronic product in time.

Therefore, it is desirable to find a way that eliminates the aforesaid problems.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is one object of the present invention to provide an induction type power supply device, which is practical for use to charge different mobile electronic products. It is another object of the present invention to provide an induction type power supply device, which is practical for use outdoors to charge different mobile electronic products with self-provided storage battery.

To achieve these and other objects of the present invention, an induction type power supply device comprises a power supply base unit having a primary inductor, and an attached induction device having a secondary inductor. When placed the attached induction device on the power supply base unit after connection of the power supply base unit to an electric outlet, the attached induction device obtains an AC signal from the power supply base unit by means of magnetic induction and converts the AC signal into a DC signal for charging an external mobile electronic product. Further, different attached induction devices with different connection interfaces can be used with the power supply base unit to charge different mobile electronic products having different connection interfaces.

In one embodiment of the present invention, the attached induction device has installed therein a charging module, which comprises a charging circuit and a rechargeable battery and connected in series between a rectifier filter circuit and a power management circuit. Normally, the rechargeable battery stores battery power. When the user goes out, the attached induction device can be used to charge a mobile electronic product when the power of the rechargeable battery of the mobile electronic product is low and when there is no any electric outlet available.

In another embodiment of the present invention, the power supply base unit has installed therein a feedback circuit, a primary control circuit, and an oscillator circuit. The feedback circuit feeds back the voltage of the resonant circuit of the primary inductor to the primary control circuit for comparison with a predetermined reference voltage so that the primary control circuit outputs a control signal to the oscillator circuit to regulate the resonant frequency subject to the comparison result.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIG. 1, an induction type power supply device in accordance with a first embodiment of the present invention is shown comprising a power supply base unit1and an attached induction device2.

The power supply base unit1comprises a connection interface11, an oscillator circuit12(either frequency modulable type or non-frequency modulable type), a driver circuit13, and a primary inductor14, which has installed therein a primary resonant circuit141and a primary coil142. The connection interface11, the oscillator circuit12, the driver circuit13and the primary inductor14are electrically connected in series.

The attached induction device2comprises a secondary inductor21having installed therein a secondary coil22and a secondary resonant circuit23, a rectifier filter circuit24, a power management circuit26, and a connection device27. The secondary inductor21, the rectifier filter circuit24, the power management circuit26and the connection device27are electrically connected in series.

After connection of the connection interface11of the power supply base unit1to an electric outlet3, the oscillator circuit12is electrically connected to produce an AC signal, which is then amplified by the driver circuit13and then sent to the primary resonant circuit141of the primary inductor14to obtain resonance, and then the AC signal is released through the primary coil142.

As stated above, the secondary inductor21of the attached induction device2has installed therein a secondary coil22and a secondary resonant circuit23. When the secondary coil22is set in proximity to the primary coil142of the power supply base unit1, it releases the AC signal to the secondary resonant circuit23for converting into DC power supply by the rectifier filter circuit24. The DC power supply thus obtained is regulated by the power management circuit26to provide the desired voltage and current to an external mobile electronic apparatus4via the connection device27. Further, the connection device27can be a USB (Universal Serial Bus), Mini USB (Mini Universal Serial Bus), or any suitable electric connection interface.

FIG. 2is a circuit block diagram of an induction type power supply device in accordance with a second embodiment of the present invention. This second embodiment is substantially similar to the aforesaid first embodiment with the exception that the attached induction device2according to this second embodiment further comprises a charging module25electrically connected in series between the rectifier filter circuit24and the power management circuit26. The charging module25comprises a storage battery252electrically connected to the power management circuit26, and a charging circuit251electrically connected in series between the rectifier filter circuit24and the storage battery252.

When the secondary coil22is set in proximity to the primary coil142of the power supply base unit1, it releases the AC signal to the secondary resonant circuit23for converting into DC power supply by the rectifier filter circuit24. The DC power supply thus obtained is then sent to the charging circuit251of the charging module25to charge the storage battery252. When travelling, a user can carry the attached induction device2separately and attach a mobile electronic apparatus to the connection device27of the attached induction device2to obtain the necessary working voltage and current from the storage battery252through the power management circuit26.

Referring toFIGS. 3˜6, during application of the present invention, connect the connection interface11of the power supply base unit1to an electric outlet3and the attached induction device2to an external mobile electronic apparatus4that can be a cellular telephone, music player or any other commercial mini electronic apparatus, and then place the external mobile electronic apparatus4with the attached induction device2on the power supply base unit1. By means of magnetic induction between the primary resonant circuit141and primary coil142of the primary inductor14and the secondary coil22and secondary resonant circuit23of the secondary inductor21, the attached induction device2charges the external mobile electronic apparatus4by means of the connection device27.

FIG. 7is a circuit block diagram of a power supply base unit for induction type power supply device in accordance with a third embodiment of the present invention. According to this third embodiment, the power supply base unit1further comprises a feedback circuit15and a primary control circuit16connected in series between the primary coil142and the oscillator circuit12. During operation, power supply is connected to the oscillator circuit12to produce an AC signal, which is amplified by the driver circuit13and then sent to the primary resonant circuit141to obtain resonance and then to be released through the primary coil142. At the same time, the feedback circuit15feeds back the AC signal to the primary control circuit16for voltage/current analysis and comparison with a predetermined reference resonance. After comparison, the primary control circuit16outputs a control signal to the oscillator circuit12subject to comparison result, causing the oscillator circuit12to regulate the optimal resonant frequency. Thus, it is not necessary to add any extra adjusting component to compensate inductor or capacitor performance. In case an extra adjusting component is used, only a skilled professional person can perform the calibration. By means of the aforesaid feedback circuit15and primary control circuit16, the adjustment of the resonant frequency is done automatically. Therefore, the invention greatly simplifies the fabrication of the power supply base unit1and improves its yield rate.

FIG. 8is a circuit block diagram of a power supply base unit for induction type power supply device in accordance with a fourth embodiment of the present invention. According to this fourth embodiment, the power supply base unit1further comprises a signal processing module17electrically connected to the primary coil142. The signal processing module17comprises a detection circuit171, a signal processing circuit172, a code-decode circuit173and a frequency mixer circuit174. The detection circuit171, the signal processing circuit172, the code-decode circuit173and the frequency mixer circuit174are connected in series. The frequency mixer circuit174is electrically connected to the primary coil141of the primary inductor14. Further, the primary control circuit16is electrically connected to the code-encode circuit173and the connection interface11. The connection interface11can be a USB (Universal Serial Bus) or Mini USB (Mini Universal Serial Bus). When the connection interface11transmits an external media signal to the primary control circuit16, the primary control circuit16converts the media signal into a data signal, and then the code-encode circuit173encodes the data signal, and then the frequency signal mixer circuit174mixes the encoded data signal with a predetermined radio frequency signal and sends the mixed signal to the primary resonant circuit141and then the primary resonant circuit141sends the signal to the primary coil142. The detection circuit171is adapted to receive a modulated data signal from the primary coil142and to remove the radio frequency signal by means of frequency demodulation, and then to send the demodulated data signal to the signal processing circuit172for data processing, enabling the processed signal to be decoded by the encode-decode circuit173and sent back to the primary control circuit16for converting into a media data for output through the connection interface11.

FIG. 9is a circuit block diagram of an attached induction device for induction type power supply device in accordance with a fifth embodiment of the present invention. According to this embodiment, the attached induction device2further comprises a signal processing module28electrically connected with the secondary resonant circuit23. The signal processing module28comprises a signal processing circuit281, a secondary control circuit282, and a modulation circuit283for signal modulation. The modulation circuit283is electrically connected to the secondary resonant circuit23. The secondary control circuit282is electrically connected to the rectifier filter circuit24. When the secondary resonant circuit23sends a data signal to the signal processing circuit281, the signal processing circuit281demodulates the data signal and then sends the demodulated data signal to the secondary control circuit282, which converts the data signal into a media signal for output through the connection device27.

Referring toFIGS. 8 and 9again, after connection of an external mobile electronic apparatus to the connection device27of the attached induction device2and connection of the connection interface11of the power supply base unit1to a computer, the connection interface11of the power supply base unit1transmits a data signal to the primary control circuit16for converting into a data signal. The converted data signal is then sent by the primary control circuit16to the code-encode circuit173for encoding. The encoded data signal is then mixed with a radio frequency signal by the frequency mixer circuit174and then sent to the primary inductor14for transmission to the secondary inductor21by means of magnetic induction. Upon receipt of the signal from the primary inductor14, the secondary inductor21sends the data signal to the signal processing circuit281for demodulation processing. After demodulation, the signal processing circuit281sends the demodulated data signal to the secondary control circuit282for converting into a media signal, which is then sent by the secondary control circuit282to the external mobile electronic apparatus4via the connection device27.

FIG. 10is a circuit block diagram of an attached induction device for induction type power supply device in accordance with a sixth embodiment of the present invention.FIG. 11illustrates an application example of the induction type power supply device in accordance with the sixth embodiment of the present invention. As illustrated inFIG. 10, the attached induction device2according to this sixth embodiment is substantially similar to that of the aforesaid fifth embodiment with the exception that this sixth embodiment eliminates the aforesaid charging module25and has an extra memory29installed therein. The memory29is electrically connected with the secondary control circuit282of the signal processing module28. According to this sixth embodiment, the connection interface11of the power supply base unit1can be connected to a computer (seeFIG. 11), allowing the computer to read storage data from the memory29, to write data into the memory29, or to make communication with an external mobile electronic apparatus being connected to the connection device27of the attached induction device2. Further, the attached induction device2can be made in the shape of a card, memory stick, or any of a variety of other configurations.

In conclusion, the invention provides an induction type power supply device, which has the following advantages and features:

1. The induction type power supply device comprises a power supply base unit1carrying a primary coil142and an attached induction device2carrying a secondary coil22. After connection of the power supply base unit1to an electric outlet3, power supply is transmitted from the power supply base unit1to the attached induction device2by means of magnetic induction to charge an external mobile electronic apparatus4that is connected to the attached induction device2. Multiple attached induction device2can be used with the power supply base unit1to charge multiple external mobile electronic apparatus4, thereby saving the cost.

2. In one embodiment of the present invention, the attached induction device2has installed therein a charging module25formed of a charging circuit251and a storage battery252and electrically connected in series between the rectifier filter circuit24and the power management circuit26. By means of the power supply base unit1, the storage battery252is charged with city power supply. When one goes out, he(she) can carry the attached induction device2and use the attached induction device2to charge a mobile electronic apparatus4in case there is no any electric outlet available.

3. Regular commercial mobile electronic apparatuses generally have at least one USB (Universal Serial Bus) and/or Mini USB (Mini Universal Serial Bus) for communication with external devices. The connection device27of the attached induction device2is compatible to most commercial mobile electronic apparatus. To fit a particular connection interface of a particular mobile electronic apparatus, a compatible attached induction device2can be selected for use with the same power supply base unit1.

4. In another embodiment of the present invention, the power supply base unit1has installed therein a feedback circuit15, a primary control circuit16and an oscillator circuit12. The feedback circuit15feeds back the voltage at the primary resonant circuit141to the primary control circuit16for voltage analysis. Subject to the analysis result, the primary control circuit16controls the oscillator circuit12to regulate input AC voltage so that the power supply base unit1provides the optimal resonant frequency.

5. When the connection device27of the attached induction device2is connected to an external mobile electronic apparatus4and the connection interface11of the power supply base unit1is connected to a computer, the connection interface11of the power supply base unit1transmits a media data signal to the primary control circuit16for converting into a data signal, which is then encoded by code-encode circuit173and mixed with a radio frequency signal by the frequency mixer circuit174and then transmitted by the primary inductor14to the secondary inductor21by means of resonant induction. Upon receipt of the data signal by the secondary inductor21, the data signal is sent by the secondary inductor21to the signal processing circuit281and the secondary control circuit282there the data signal is demodulated and converted into a media signal and then transmitted to the external mobile electronic apparatus4by the secondary control circuit282. Thus, the external mobile electronic apparatus4can receive data from the computer.

A prototype of induction type power supply device has been constructed with the features ofFIGS. 1˜11. The induction type power supply device functions smoothly to provide all of the features disclosed earlier.