KR20080094468A - Multi type adapter for charging contact-less chargeable battery and battery charging set having the same - Google Patents

Abstract

A multi-type adapter for charging a contactless chargeable battery and a battery charging set having the same are provided to charge a battery by using a multi-type adapter with a relatively small volume when a user moves resistance temporally. A multi-type adapter for charging a contactless chargeable battery(300) includes a power supply unit for supplying power by converting a received commercial alternative current into a direct current. A charged power supply unit directly supplies the power supplied from the power supply unit to the contactless chargeable battery by using a pair of power lines(103,104). A selection unit(105) selectively supplies the power supplied from the power supply unit to a contactless charging pad(200) to transmit the charged power to the contactless battery by forming magnetic field in an external space or the charged power supply unit.

Description

Multi type adapter for charging contact-less chargeable battery and Battery charging set having the same}

The following drawings attached to this specification are illustrative of preferred embodiments of the present invention, and together with the detailed description of the invention to serve to further understand the technical spirit of the present invention, the present invention is a matter described in such drawings It should not be construed as limited to

1 is a conceptual diagram illustrating a battery and a charger employing a contactless charging method according to the prior art.

2 is a block diagram schematically showing the configuration of a battery and a charger employing a contactless charging method according to the prior art.

3 is a conceptual diagram illustrating a battery charge set according to a preferred embodiment of the present invention.

4 is a block diagram schematically showing the configuration of a battery charge set according to a preferred embodiment of the present invention.

Figure 5 is a block diagram schematically showing the configuration of the selection means implemented by the electronic switch in accordance with a preferred embodiment of the present invention.

6 is a block diagram schematically illustrating a configuration of a battery charge set according to another embodiment of the present invention.

<Description of main reference numerals in the drawings>

100.Multi-type charging adapter 101 ... Power input terminal

102 Adapter body 103 ... First power line

104 second power line 105 ... selection switch

110 ... power supply 111 ... overvoltage cut-off filter

112 Rectifier 113 Constant voltage supply

120 ... selection means 121 ... electronic selector switch

122 ... toggle switch control unit 130 ... charging power supply unit

200 ... contactless charging pad 210 ... primary coil

220.High frequency power driver 230.Pad confirmation signal transmission means

300 ... contactless battery 305 ... mobile communication terminal

310 ... secondary coil 320 ... rectifier

330 Constant voltage / constant current supply 340 Battery acknowledgment signal transmission means

350 ... battery cell

The present invention relates to a multi-type charging adapter and a contactless battery charging set having the same, and more particularly, to a multi-type charging adapter capable of supplying charging power using a contact method and a contactless method to an electronic device having a contactless battery. And a contactless battery charging set having the same.

 Recently, a contactless charging technology for charging a battery in a state of being coupled with a charger in a contactless manner by an electromagnetic induction phenomenon for charging a personal portable device such as a mobile phone, PDA, notebook, etc. has been proposed.

1 schematically shows a configuration of a battery and a charger employing a contactless charging method according to the prior art.

Referring to FIG. 1, the charger 10 receives power from a commercial AC power source 20 and outputs a high frequency AC current, and a high frequency AC current from the high frequency power driver 30. It is provided with a primary coil 40 that is applied to form a magnetic field (M).

In addition, the battery 50 may include a battery cell 60 in which electrical energy is charged, a secondary side coil 70 in which a high frequency alternating current is induced according to a linkage of the magnetic field M generated in the primary side coil 40, and a secondary side. A rectifier 80 converts the high frequency AC current induced by the coil 70 into a DC current, and a constant voltage / constant current supply 90 that applies the DC current rectified by the rectifier 80 to the battery cell 60.

Here, the constant voltage / constant current supply unit 90 is a known circuit element widely used in a battery charging device. The constant voltage / constant current supply unit 90 supplies a constant current to the battery cell 60 at the beginning of charging, but when the charging voltage of the battery cell 60 gradually increases and exceeds a specific reference value, the supply of current decreases and the voltage is decreased. Function to keep constant.

As described above, the battery 50 and the charger 10 employing the contactless charging method according to the related art are configured in one set, so that the contactless charger 10 is necessary to charge the contactless battery 50. Do. Therefore, when temporarily moving a residence, such as when traveling, there is an inconvenience that must carry a relatively large contactless charger 10 than the conventional contact type charger for charging the contactless battery 50.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to provide a multi-type charging adapter and a contactless battery charging set including the same, in which a user can select and charge a contact method and a contactless method as necessary. .

In order to achieve the above object, the multi-type charging adapter according to an aspect of the present invention is a charging adapter for transferring charging power to a contactless battery charged by an electromagnetic induction phenomenon, and receives a commercial AC current as a DC power source. A power supply unit converting and supplying the power supply unit; A charging power supply unit supplying power supplied from the power supply unit directly to a contactless battery using a power line; And selection means for selectively supplying the power supplied from the power supply unit to a non-contact charging pad or the charging power supply unit for forming a magnetic field in an external space to transmit charging power to the contactless battery.

The selection means may be a mechanical changeover switch operated by a user's operation, or the electronic changeover switch operated by a changeover signal input from the outside, and receiving a confirmation signal from a contactless charging pad or a contactless battery to switch the electronic changeover switch. It may be made of a switch control means for controlling the.

The power supply unit is an overvoltage cut-off filter unit for receiving a commercial AC current to block the overvoltage current; And a rectifying unit rectifying the alternating current passing through the filter unit and converting the alternating current into a direct current.

According to another aspect of the present invention, a battery charging set includes a magnetic field generator that receives an AC current and forms a magnetic field in an external space, and a high frequency power driver that converts electric power supplied from the outside to apply a high frequency AC current to the magnetic field generator. Contactless charging pad comprising a; A high frequency AC current induction unit in which a high frequency AC current is induced by a magnetic field generated by an external contactless charger, a rectifying unit receiving the induced high frequency AC current and converting it into a DC current, and receiving a DC current from the rectifying unit or an external device. A contactless battery including a constant voltage / constant current supply unit supplying a voltage or a current required for charging a battery cell; And a power supply unit which receives commercial AC current, converts the power into DC power, and supplies the power supplied from the power supply unit directly to a contactless battery using a power line, and the power supplied from the power supply unit. It includes a multi-type charging adapter including a selection means for selectively supplying the contactless charging pad or the charging power supply unit.

The selecting means may be a mechanical changeover switch operated by a user's manipulation. The contactless charging pad may include a pad acknowledgment signal transmitting means for generating and transmitting a confirmation signal for distinguishing a contactless charging pad, and the contactless battery generates and transmits a confirmation signal for distinguishing that the contactless battery is non-contact battery. A battery confirmation signal transmission means, the selection means comprising: an electronic changeover switch operated by a changeover signal input from the outside; And switch control means for receiving a confirmation signal from the pad confirmation signal transmission means or the battery confirmation signal transmission means to control the switching of the electronic changeover switch.

The power supply unit of the multi-type charging adapter is an overvoltage cut-off filter unit for receiving a commercial AC current to block the overvoltage current; And a rectifying unit rectifying the AC current passing through the filter unit and converting the AC current into a DC current. The contactless charging pad may include a constant voltage supply unit configured to convert power supplied from the rectifying unit and supply the converted current to the high frequency power driver. .

The power supply unit of the multi-type charging adapter is an overvoltage cut-off filter unit for receiving a commercial AC current to block the overvoltage current; A rectifying unit rectifying the AC current passing through the filter unit and converting the AC current into a DC current; And a constant voltage supply unit configured to convert the power supplied from the rectifier and supply the power to the high frequency power driver of the contactless charging pad.

The high frequency power driver includes a pulse signal generator for outputting a pulse signal for generating high frequency AC power; And a power driver configured to receive the pulse signal and generate a high frequency AC current in the form of a pulse by switching the constant voltage DC input from the constant voltage supply unit at high speed.

The pulse signal generator preferably modulates and outputs the width of the pulse current, the frequency of the pulse current, the amplitude of the pulse or the number of pulses.

The high frequency power driver may intermittently apply a high frequency AC current to the magnetic field generator.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

3 is a conceptual diagram illustrating a battery charge set according to a preferred embodiment of the present invention.

Referring to FIG. 3, a battery charge set according to an embodiment of the present invention includes a multi-type charging adapter 100, a contactless charging pad 200, and a contactless battery 300 mounted in a mobile communication terminal 305. do.

The multi-type charging adapter 100 includes a power input terminal 101 capable of receiving commercial power, an adapter body 102 that receives commercial power and generates and supplies power for charging a battery, and the adapter body 102. A first power line 103 connected to an internal circuit of the power supply unit 100 and directly transferring power output from the adapter body 102 to a contactless battery 300 mounted on the mobile communication terminal 305, and the adapter body ( A second power line 104 connected to an internal circuit of the 102 and transmitting power output from the adapter body 102 to the contactless charging pad 200, and connected to an internal circuit of the adapter body 102. A selector switch 105 may be selected to supply charging power output from the adapter body 102 to the first power line 103 or the second power line 104.

The contactless charging pad 200 is connected to the second power line 104 to receive power supplied from an internal circuit of the adapter body 102. Then, using the received power to form a magnetic field for transmitting power to the contactless in the external space.

The contactless battery 300 induces a high frequency alternating current using a magnetic field generated from the outside and supplies power for charging the battery cell. In addition, the contactless battery 300 is connected to the first power line 103 directly receives the power supplied from the internal circuit of the adapter body 102, and supplies a voltage or current required for charging the battery cell. .

4 is a block diagram schematically illustrating the configuration of a battery charge set according to an embodiment of the present invention.

Referring to FIG. 4, the multi-type charging adapter 100 provided in the battery charging set according to the embodiment of the present invention includes a power supply unit 110, a selection unit 120, and a charging power supply unit 130.

The power supply unit 110 receives commercial power and converts it into direct current to supply power required for the contactless charging pad 200 and the contactless battery 300. In detail, the power supply unit 110 includes an overvoltage blocking filter unit 111 for blocking an overvoltage applied from commercial power, a rectifying unit 112 for converting AC power passing through the overvoltage blocking filter unit 111 into DC power; The constant voltage supply unit 113 receives the rectified DC power, converts the voltage into a voltage (eg, DC 22V) necessary for the contactless charging pad 200 and the charging power supply unit 130, and delivers the voltage to the selection unit 130. It may include.

The selecting means 120 is a means for selectively supplying the power applied from the power supply 110 to the contactless charging pad 200 or the charging power supply 130.

The selection means 120 may be a mechanical changeover switch whose output is selected by a selection switch 105 mounted to the outside of the multi-type charging adapter 100. Accordingly, when the user selects an output object and switches the selection switch 105, the selection means 120 receives the power applied from the power supply unit 110 in response to the switching of the selection switch 105. It supplies to the 200 or the charging power supply unit 130.

The multi-type charging adapter 100 according to the embodiment of the present invention directly supplies the power required for charging the battery cell 350 to a contact formed in the contactless battery 300 using the first power line 103. Accordingly, the charging power supply unit 130 converts the voltage (for example, DC 22V) received from the power supply unit 110 to charge the battery cell 350 included in the contactless battery 300 (for example, Supply it with DC 4.2V).

The contactless charging pad 200 according to the exemplary embodiment of the present invention includes a primary coil 210 and a high frequency power driver 220. The high frequency power driver 220 generates a magnetic field by applying a high frequency AC current of several tens of KHz to the primary coil 210 through a high speed switching operation. For example, the high frequency power driver 220 applies a high frequency AC current of 80 KHz to the primary coil 210. When a magnetic field is generated by the high frequency AC current in the primary coil 210, the charging power is transmitted to the battery 300 side in a contactless manner by the electromagnetic induction phenomenon.

Preferably, a known switching mode power supply (SMPS) may be employed as the high frequency power driver 220, but the present invention is not limited thereto.

The contactless battery B according to an exemplary embodiment of the present invention includes a charging circuit module including a secondary coil 310, a rectifier 320, and a constant voltage / constant current supply unit 330, and charging by the charging circuit module is performed. It comprises a battery cell 350 made.

The secondary coil 310 generates a high frequency AC current by an electromagnetic induction phenomenon while a high frequency AC current is applied to the primary coil 210 provided in the charger C. At this time, the magnitude of the high frequency alternating current induced in the secondary coil 310 is proportional to the magnetic flux chained to the secondary coil 310.

The rectifier 320 smoothes the high frequency AC current induced by the secondary coil 310 to convert the DC current.

The constant voltage / constant current supply unit 330 charges the battery cell 350 by applying the DC power rectified by the rectifier 320 to the battery cell 350, but initially charges the battery cell 350 in the constant current mode. When the charging voltage exceeds a predetermined reference, the battery cell 350 is charged in the constant voltage mode to maintain a constant charging voltage instead of reducing the current.

In addition, the constant voltage / constant current supply unit 330 selectively applies the power supplied by the charging power supply unit 130 of the multi-type charging adapter 100 through the first power line 103 to the battery cell 350 to thereby charge the battery cell 350. ) Can be charged.

In the exemplary embodiment of the present invention, the selecting means 120 provided in the multi-type charging adapter 100 is a mechanical switching switch. Alternatively, the selecting means 120 may be implemented as an electronic switch. That is, the multi-type charging adapter 100 has a single power line connected to the contactless charging pad 200 and the contactless battery 300, and the contactless charging pad 200 and the contactless battery 300 are connected to each other. After confirming, the power supplied from the power supply unit 110 provided in the multi-type charging adapter 100 is automatically transferred to the contactless charging pad 200 or the charging power supply unit 130.

Figure 5 is a block diagram schematically showing the configuration of the selection means implemented by the electronic switch in accordance with a preferred embodiment of the present invention.

4 and 5, the contactless charging pad 200 and the contactless battery 300 transmit signals for confirming that the contactless charging pad 200 and the contactless battery 300 are connected, respectively. The pad confirmation signal transmission means 230 and the battery confirmation signal transmission means 340 are provided. The selection means 120 includes an electronic changeover switch 121 and a changeover switch controller 122. The electronic switching switch 121 connects the power supplied from the power supply unit 110 to the contactless charging pad 200 or the charging power supply 130 according to a control signal applied from the switching switch controller 122. The changeover switch controller 122 receives a signal transmitted from the pad confirming signal transmitting means 230 and the battery confirming signal transmitting means 340, and indicates that the received signal is a battery or a signal indicating that the received signal is a pad according to a form of a signal transmitted in advance. The control signal is transmitted to the electronic switching switch 121 by distinguishing whether the signal is represented.

The pad acknowledgment signal transmitting means 230 and the battery acknowledgment signal transmitting means 340 respectively transmit confirmation signals in which signal widths, magnitudes, frequencies, and patterns are different from each other, and the switch controller 122 receives the received confirmation signals. The width, magnitude, frequency, pattern, and the like of the signal are compared with the predetermined confirmation signal to determine the corresponding confirmation signal. As a result, the switch controller 122 may confirm that the contactless charging pad 200 and the contactless battery 300 are connected to a power line connected to the multi-type charging adapter 100.

Furthermore, in the preferred embodiment of the present invention, the power supply unit 110 provided in the multi-type charging adapter 100 is provided with a constant voltage supply unit 113, but as an alternative thereto, the constant voltage supply unit 113 is contactless charging It is also possible to be provided in the pad 200 (refer FIG. 6).

Accordingly, the power supply unit 110 provided in the multi-type charging adapter 100 does not include the constant voltage supply unit 113, but supplies the rectified DC power through the rectifying unit 112. In addition, the charging power supply unit 130 provided in the multi-type charging adapter 100 converts the rectified DC power into a voltage (for example, DC 4.2V) required for charging the battery cell 350, thereby providing a constant voltage / constant current supply unit 330. Supplies). In addition, the constant voltage supply unit 113 provided in the contactless charging pad 200 converts the rectified DC power into a voltage having a magnitude required by the high frequency power driver 220 and supplies it.

The battery charge set having the above-described configuration allows the user to selectively connect the power lines 103 and 104 connected to the multi-type charging adapter 100 to the electronic device (eg, the mobile communication terminal 305) having the contactless battery 300. May be directly connected to the contactless charging pad 200.

Hereinafter, the operation of the battery charge set according to the embodiment of the present invention will be described with reference to the aforementioned components.

First, the user switches the selection switch 105 provided in the multi-type charging adapter 100 to a state of selecting the second power line 104, and contacts the second power line 104 connected to the multi-type charging adapter 100 without contact. Connect to the charging pad 200. Then, the electronic device (for example, the mobile communication terminal 305) equipped with the contactless battery 300 is positioned on the contactless charging pad 200.

Then, the power supply unit 110 provided in the multi-type charging adapter 100 converts the input commercial power into direct current power and supplies it to the selection means 120. Since the selecting means 120 is switched to the state in which the power supply unit 110 and the contactless charging pad 200 are connected, the DC power is transmitted to the contactless charging pad 200.

The high frequency power driver 220 of the contactless charging pad 200 supplied with the DC power from the multi-type charging adapter 100 applies a high frequency AC current to the primary coil 210 for a short time at a predetermined time interval, 1 The secondary coil 210 forms a magnetic field around each time a high frequency AC current is applied.

Accordingly, the magnetic flux is chained to the secondary coil 310 of the contactless battery 300 placed in the magnetic field region by the electromagnetic induction phenomenon, and the high frequency AC current is induced in the secondary coil 310.

The high frequency AC current induced in the secondary coil 310 is converted into a DC current by the rectifier 320 and then applied to the battery cell 350 via the constant voltage / constant current supply unit 330. Then, as the battery cell 350 is gradually charged, the voltage of both ends of the battery cell 350 increases until it is fully charged.

The constant voltage / constant current supply unit 330 charges the battery cell 350 in the constant current mode until the charging voltage of the battery cell 350 increases to a certain level, but when the voltage of the battery cell 350 increases by a predetermined level or more, the constant voltage mode Charges the battery cell 350 at.

On the other hand, the user switches the selection switch 105 provided in the multi-type charging adapter 100 to the state of selecting the first power line 103, and the contactless first power line 103 connected to the multi-type charging adapter 100 is contactless. It is connected to an electronic device (eg, mobile communication terminal 305) having a battery 300. Then, the electronic device (for example, the mobile communication terminal 305) equipped with the contactless battery 300 is positioned on the contactless charging pad 200.

Then, the power supply unit 110 provided in the multi-type charging adapter 100 converts the input commercial power into direct current power and supplies it to the selection means 120. Since the selecting means 120 is switched to a state in which the power supply unit 110 and the contactless battery 300 are connected, the DC power is supplied to the charging power supply unit 130. The charging power supply unit 130 converts the DC power into power as required by the constant voltage / constant current supply unit 330 included in the contactless battery 300 and supplies the same to the constant voltage / constant current supply unit 330. As a result, the converted DC power is transmitted to the constant voltage / constant current supply unit 330 through the first power line 103, and the constant voltage / constant current supply unit 330 is a battery cell 350 in the constant voltage mode and the constant current mode as described above. Charge cell 350.

In the exemplary embodiment of the present invention, the selecting means 120 is illustrated as a mechanical changeover switch. Alternatively, the selection means 120 may be implemented as an electronic changeover switch. When the selection means 120 is implemented as an electronic changeover switch, only one power line is connected to the multi-type charging adapter 100, and the user operates the selection switch 105 separately or uses the first and second power lines as necessary. There is no need to select and connect. That is, the user only needs to couple the power line connected to the multi-type charging adapter 100 to the contactless charging pad 200 or the contactless battery 300 as necessary.

Furthermore, when the user couples the power line connected to the multi-type charging adapter 100 to the contactless charging pad 200, the pad confirmation signal transmitting means 230 provided in the contactless charging pad 200 selects the pad confirmation signal. Transmit switch control unit 122 of (120). The switch switch control unit 122 controls the combination of the electronic switch switch 421 in consideration of the pad check signal. That is, the changeover switch control unit 122 controls the electronic changeover switch 421 to connect the power supply unit 110 and the contactless charging pad 200. Similarly, when the user couples the power line connected to the multi-type charging adapter 100 to the contactless battery 300, the user receives the battery confirmation signal from the battery confirmation signal transmission means 340 provided in the contactless battery 300 The selection means 120 connects the power supply unit 110 and the charging power supply unit 130.

Using such a battery charging set, the user can freely charge the battery as needed by using the contactless charging method and the contactless method.

Although the present invention has been described above by means of limited embodiments and drawings, the present invention is not limited thereto and will be described below by the person skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of the claims.

According to the battery charging set of the present invention, by supporting both contact and contactless charging, the user can selectively charge as needed.

In addition, when temporarily moving the residence, such as when traveling can be used to charge the battery using a relatively small multi-type charging adapter, it is possible to reduce the load when moving.

Claims (12)

In the charging adapter for transferring the charging power to the contactless battery charged by the electromagnetic induction phenomenon, A power supply unit which receives commercial AC current and converts the power into DC power; A charging power supply unit supplying power supplied from the power supply unit directly to a contactless battery using a power line; And And a selection means for selectively supplying the power supplied from the power supply unit to a contactless charging pad or a charging power supply unit for forming a magnetic field in an external space to transmit charging power to the contactless battery. Charging adapter. The method of claim 1, The selection means is a multi-type charging adapter, characterized in that the mechanical changeover switch operated by the user's operation. The method of claim 1, The selection means, An electronic changeover switch operated by a changeover signal input from the outside; And And a switch control means for receiving a confirmation signal from a contactless charging pad or a contactless battery to control the switching of the child switching switch. The method of claim 1, The power supply unit, An overvoltage cutoff filter unit which receives a commercial AC current and cuts off the overvoltage current; And And a rectifying unit rectifying the alternating current passing through the filter unit and converting the alternating current into a direct current. A contactless charging pad including a magnetic field generator for receiving an AC current to form a magnetic field in an external space and a high frequency power driver for converting electric power supplied from the outside to apply a high frequency AC current to the magnetic field generator; A high frequency AC current induction unit in which a high frequency AC current is induced by a magnetic field generated by an external contactless charger, a rectifying unit receiving the induced high frequency AC current and converting it into a DC current, and receiving a DC current from the rectifying unit or an external device. A contactless battery including a constant voltage / constant current supply unit supplying a voltage or a current required for charging a battery cell; And A power supply unit that receives commercial AC current and converts the power into a DC power source; a charging power supply unit supplying the power supplied from the power supply unit directly to a contactless battery using a power line; And a multi-type charging adapter including selection means for selectively supplying the contactless charging pad or the charging power supply unit. The method of claim 5, And said selecting means is a mechanical changeover switch operated by a user's operation. The method of claim 5, The contactless charging pad is provided with a pad confirmation signal transmission means for generating and transmitting a confirmation signal to distinguish the contactless charging pad, The contactless battery is provided with a battery confirmation signal transmission means for generating and transmitting a confirmation signal to distinguish the contactless battery, The selection means, An electronic changeover switch operated by a changeover signal input from the outside; And And a switch control means for receiving a confirmation signal from the pad confirmation signal transmission means or the battery confirmation signal transmission means to control the switching of the electronic changeover switch. The method of claim 5, The power supply unit of the multi-type charging adapter, An overvoltage cutoff filter unit which receives a commercial AC current and cuts off the overvoltage current; And And a rectifying unit rectifying the AC current passing through the filter unit and converting the AC current into a DC current. Contactless charging pad, And a constant voltage supply unit configured to convert the power supplied from the rectifier unit and supply the converted power to the high frequency power driver. The method of claim 5, The power supply unit of the multi-type charging adapter, An overvoltage cutoff filter unit which receives a commercial AC current and cuts off the overvoltage current; A rectifying unit rectifying the AC current passing through the filter unit and converting the AC current into a DC current; And And a constant voltage supply unit configured to convert the power supplied from the rectifier unit and supply the converted power to the high frequency power driver of the contactless charging pad. The method of claim 5, The high frequency power drive unit, A pulse signal generator for outputting a pulse signal for generating high frequency AC power; And And a power driver configured to receive the pulse signal and to generate a high frequency alternating current in the form of a pulse by switching a constant voltage direct current input from the constant voltage supply unit at a high speed. The method of claim 10, And the pulse signal generator modulates the width of the pulse current, the frequency of the pulse current, the amplitude of the pulse or the number of pulses to output the modulated output. The method of claim 5, And the high frequency power driver intermittently applies a high frequency alternating current to a magnetic field generating unit.

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