JPH11176676A - Small-sized noncontact transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a smaller noncontact transmitter by constituting a ferrite core, a coil, and an electric circuit board integrally so as to materialize downsizing of a transmission part and reduction of number of parts enough. SOLUTION: This is a noncontact type of transmitter which includes coils 1 and 2, and 6 and 7 opposed to each other across space. Its one hand serves as input or transmission side, and the other hand serves as output or reception side, and transmits signals or power, making use of the electromagnetic inductive active generated between opposed coils 1 and 2, and 6 and 7, the coils 1 and 2, and 6 and 7 are arranged at the ferrite cores 21 and 31 as the base material of a printed circuit board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-sized non-contact transmission device for transmitting electric power, a signal, or both at the same time in a non-contact manner by electromagnetic induction generated between coils.

[0002]

2. Description of the Related Art Conventionally, a coil formed by winding a rectangular ferrite core is opposed to a coil through an air gap, one of which is an input side coil,
2. Description of the Related Art There is known a transmission device in which the other is disposed in an output side coil and transmits the signal in a non-contact manner by utilizing an electromagnetic induction effect generated between these opposed coils. It is configured using an electric circuit board such as a dedicated FPC (flexible wiring circuit board) on which the above-described coil and accompanying electronic components are mounted.

[0003]

However, in order to increase the inductance and reduce the DC resistance of the coil, the ferrite core is a Mn-Zn based material having a large magnetic flux density (B) and a high magnetic permeability (μ). Had adopted a ferrite core. Therefore, the electric resistance value of the core is low (about 1 Ω · m), and the coil and associated electronic components cannot be directly arranged on the core, and a flexible electric circuit board is used as an insulator. Furthermore, Mn-Zn ferrite can be sintered only in a furnace in an atmosphere (inert gas) and cannot be supplied in large quantities at low cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the technical problem thereof is that a ferrite core, a coil, and an electric wire are required to sufficiently reduce the size, weight, and number of parts of a transmission unit. An object of the present invention is to provide a further compact non-contact transmission device by integrally configuring a circuit board.

[0005]

According to the present invention, coils facing each other via a gap are provided, one of which is an input side or a transmission side and the other is an output side or a reception side. A non-contact transmission device for transmitting a signal and electric power by utilizing a generated electromagnetic induction action, wherein the coil comprises:
A compact non-contact transmission device characterized by being disposed on a ferrite core as a base material of a substrate having a wiring pattern, respectively.

Further, according to the present invention, in the above-mentioned compact non-contact transmission device, the opposed coil is constituted by a plane meander type coil or a plane spiral coil, and the number of each is at least one. The characteristic small contactless transmission device is obtained.

Further, according to the present invention, in any of the above-mentioned compact non-contact transmission devices, the ferrite core is made of a Ni-Zn ferrite or a Ni-Zn-Cu ferrite having a high electric resistance. A compact non-contact transmission device characterized in that the ferrite core is used as a base material of the substrate.

Further, according to the present invention, in any of the above-mentioned compact non-contact transmission devices, the ferrite core is made of Mn-Zn ferrite having a high magnetic flux saturation density, and the ferrite core is used as a base material of the substrate. In addition, a compact non-contact transmission device is provided, which is provided with an insulator interposed between the ferrite core and the wiring pattern for the sake of greenery.

Further, according to the present invention, in any one of the above-mentioned compact non-contact transmission devices, the wiring pattern has a connection portion and an external connection terminal for mounting an input side coil and a resonance capacitor on an input side. A small contactless transmission device characterized in that the output side includes a connection portion for mounting an output side coil, a resonance capacitor, a rectifier diode, and a smoothing capacitor, respectively, and an external connection terminal portion. .

According to the present invention, in any of the above-mentioned small non-contact transmission devices, the ferrite core may include
The electric resistance (ρ) is 10 kΩ · m or more in the case of i-Zn ferrite, and 1 MΩ · m or more in the case of Ni-Zn-Cu ferrite, and the saturation magnetic flux density (B) is 300 mT. As described above, the magnetic permeability (μ) is 500 or more, and when made of Mn—Zn-based ferrite, the electric resistance (ρ) is 5 Ω · m or more, the saturation magnetic flux density (B) is 500 mT or more, and the magnetic permeability is (Μ) is 200
A small contactless transmission device characterized by being 0 or more is obtained.

Further, according to the present invention, in any one of the above-mentioned compact non-contact transmission devices, the ferrite core may include N
A compact non-contact transmission device comprising a Ni-based ferrite selected from the group consisting of i-Zn-based and Ni-Zn-Cu-based ferrite and having a frequency used for transmission of 200 kHz or more is obtained.

Further, according to the present invention, in any one of the above-mentioned compact non-contact transmission devices, the ferrite core may be made of M
A compact non-contact transmission device comprising an n-Zn ferrite and having a frequency used for transmission of 200 kHz or less is obtained.

Further, according to the present invention, in any of the above-mentioned small non-contact transmission devices, the thickness of the ferrite core is within a range of 0.1 to 5 mm. can get.

Further, according to the present invention, there is provided a small-sized non-contact transmission device characterized in that any one of the above-mentioned small-sized non-contact transmission devices uses a method in which a contact that contributes to transmission is eliminated.

Further, according to the present invention, in any one of the above-mentioned compact non-contact transmission devices, each of the ferrite cores includes an electric circuit including a coil on one surface, and is mounted on an outer portion of the electric circuit. A compact non-contact transmission device characterized in that leakage magnetic flux generated from an electric circuit is suppressed to 40% or less.

Further, according to the present invention, in any one of the above-mentioned compact non-contact transmission devices, a ferrite core having the output side or the reception side coil formed on one side is provided on the other side opposite to the one side by 0 to 2 mm. Characterized in that the charging member is arranged through the gap or the at least the charging member and the ferrite core in the charging member and the electric circuit are separated from the ferrite core. A transmission device is obtained.

Further, according to the present invention, in any one of the above-mentioned compact non-contact transmission devices, a gap which is an interval between the coils is 0 to 5 mm (however, 0 is not included). A non-contact transmission device is obtained.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing a small contactless transmission device according to an embodiment of the present invention. FIG. 2 is a circuit diagram of the small contactless transmission device of FIG.

As shown in FIG. 1, a small contactless transmission device 1
Numeral 0 indicates that the reception unit 20 and the transmission unit 30 are arranged with the spiral coils 1 and 2 and the spiral coils 6 and 7 facing each other.

The receiving section 20 is provided with an insulator 22 on one surface of a ferrite core 21 and a wiring pattern 23 made of copper foil thereon. The wiring pattern 23 includes coil connection portions 23a and 23 for mounting the coils 1 and 2, respectively.
b, 23c and 23d, resonance capacitor connecting portions 23e and 23f for mounting the resonance capacitors,
Diode connection part 23 for mounting detection diode
g and 23h, smoothing capacitor connecting portions 23i and 23j for mounting the smoothing capacitor, and external terminal portions 23k and 23k.
23l.

The connecting portion 23 of each pattern of the insulator 22
In each of a to 23j, two winding coils 1 and 2, a resonance capacitor 3, a rectifying / detecting diode 4, and a smoothing capacitor 5 are mounted, respectively, and the electric wires are connected as shown by a wiring 23 '. A circuit is configured. Note that reference numerals 11, 1
Reference numeral 1 denotes an external connection terminal, which corresponds to a pattern indicated by reference numerals 23k and 23l.

The transmitting unit 30 includes a ferrite core 31
The wiring pattern 33 is also provided on one side of the
Is provided. The wiring pattern 33 includes coils 6,
7 for mounting the coil 7
c, 33d and resonance capacitor connecting portions 33e, 33f for mounting the resonance capacitors, and external connecting portions 33g, 3g.
3h are formed. The spiral coils 6 and 7 and the resonance capacitor 8 are mounted on the wiring pattern 33 to form an electric circuit.

The facing distance between the transmitting unit 30 and the receiving unit 20 is
5 mm or less.

The pair of coils 1, 2, and 6, 7
Are flat spiral coils, but may be flat meander coils.

The ferrite cores 21 and 31 have a thickness of 0.1 to 5 mm and have a high saturation magnetic flux density.
Zn-based ferrite can be used. This Mn-Z
The n-type ferrite has an electric resistance (ρ) of 5 Ω · m or more, a saturation magnetic flux density (B) of 500 mT or more, and a magnetic permeability (μ) of 2000 or more. Since the Mn-Zn-based ferrite has low insulating properties, the wiring patterns 23 and 33 are applied via the insulators 22 and 32. Alternatively, Mn-Zn
In the system ferrite core, an insulating layer can be applied and dried directly on the core in advance, and an electric circuit can be formed on the insulating layer in a subsequent printing process. Further, an FPC provided with a wiring pattern can also be used. When a Mn—Zn ferrite core is used, the magnetic permeability (μ) is large in a frequency band of 200 kHz or less, and the transmission frequency is 200 μm.
kHz or less is preferable.

The ferrite cores 21 and 31 are made of Ni—Zn having a thickness of 0.1 to 5 mm and high electric resistance.
System ferrite or Ni-Zn-Cu system ferrite can be used. The Ni—Zn ferrite has an electric resistance (ρ) of 10 kΩ · m or more, and the Ni—Zn—Cu ferrite has an electric resistance (ρ) of 1 MkΩ · m.
The saturation magnetic flux density (B) is 300 mT or more, and the magnetic permeability (μ) is 500 or more. When using these Ni-based ferrites, an electric circuit can be formed by forming a wiring pattern directly on one surface of the ferrite core. Therefore, an electric circuit can be formed directly on the Ni-based ferrite core by a printing process. When a Ni-based ferrite core is used, since the magnetic permeability (μ) is high in a frequency band of 200 KHz or more, the transmission frequency is 2 kHz.
00 kHz or more is preferable.

Further, since the ferrite cores 21 and 31 have large electric resistance, an electric circuit is directly formed on the cores by printing. The coils 1, 2, 6 and 7 are arranged on the ferrite cores 21 and 31. The thickness of the Ni ferrite core used in these small contactless tactile transmitters is 0.1 to
The reason for selecting the Ni ferrite core as the ferrite core is preferably 5.0 mm because the Ni ferrite core has high electric resistance (10 kΩ · m or more) and excellent high frequency characteristics. Further, the reason for limiting the thickness of the Ni ferrite core to 0.1 to 5.0 mm is as follows.
When the thickness is 0.1 mm or more, the effect of capturing magnetic flux is clearly recognized, but when the thickness is 5.0 mm or more, the effect of reducing the thickness is significantly reduced.

The ferrite cores 21 and 31 are opposed to each other in parallel, and comb-shaped or spiral coils are arranged on the ferrite cores 21 and 31 so that a magnetic flux penetrates inside the coils.

As shown in FIG. 2, a frequency conversion circuit 12 having an outlet 13 for supplying external signal power is connected to an external connection terminal of the transmission unit 30. The transmitting unit 30 and the receiving unit 20 transmit power and / or signals via the spiral coils 6 and 7 and the spiral coils 1 and 2. Note that a charging member (not shown) related to charging of a supercapacitor, a secondary battery, or the like is connected to the external connection terminal portions 11, 11.

The small contactless transmission device 10 having such a configuration
Is a non-contact transmission using the electromagnetic induction generated between the coils 1, 2, 6 and 7 that are opposed to each other through the air gap. Section and an electrical circuit section for reception.

Furthermore, ferrite cores 11 and 12 made of a Ni-based ferrite core are mounted at least on the outer side of the electric circuit portion on the receiving side. This Ni-based ferrite core has an effect of preventing magnetic flux leakage.

In the case of such a small contactless transmission device 10, the transmission efficiency is remarkably improved as described later. For example, if the opposing coils 6 and 7 include an output-side electric circuit portion, a configuration (not shown) in which a capacitor is inserted into the output-side portion may be mentioned. Incidentally, when a capacitor is inserted in the output side portion of the coils 1 and 2, the conversion efficiency is improved, but this is because the supply power consumed for excitation is reduced.

Some of these small contactless transmission devices 10
In this case, the transmission efficiency is improved by mounting a Ni ferrite core outside the coils 6 and 7 on the receiving side or the coils 1, 2 and 6, 7 on the transmitting side and the receiving side. The reason is that the magnetic flux generated from the coils 1, 2 and 6, 7 is N
This is because the i-ferrite core passes through the core in a concentrated manner, thereby reducing leakage magnetic flux and contributing to transmission. This leakage flux is about 40% or less.

In addition, in the above-mentioned embodiment, the reason why the opposed coils 1, 2 and 6, 7 are planar spiral coils is that a plurality of air-core coils are densely arranged on the same plane. This is because the amount of magnetic flux increases accordingly, and the magnetic flux contributing to transmission can be increased.

When a plurality of planar spiral coils are connected to form a planar spiral coil in a plurality of opposing sets, a connection method in which the generated magnetic fluxes are all in the same direction, and a method of connecting magnetic fluxes between adjacent coils in the set. There is a method of connecting in the opposite direction. The latter configuration has the advantage that the magnetic fluxes are strengthened with each other, the magnetic flux leakage to the outside is small, and the influence on peripheral devices can be reduced.

In such a configuration, when the planar spiral coils are arranged in close contact with each other, the mutual inductance between adjacent coils works effectively in addition to the mutual inductance between the primary and secondary coils, so that the conversion efficiency is remarkable. Can be improved.

[0038]

As described above, according to the compact non-contact transmission device of the present invention, the electromagnetic induction effect generated between the coils facing each other through the air gap prevents the Ni mounted at least outside the output side portion of the coil. Since the magnetic flux leakage is prevented by the system ferrite, the transmission efficiency is remarkably improved. As a result, the thickness of a non-contact transmission device or a small non-contact transmission device in which the input side of an opposing coil is connected to a signal source is significantly reduced, and effective applications in various fields are expected.

Further, according to the present invention, by using the ferrite core itself as the base material of the electric circuit board, it is possible to improve the high-frequency characteristics and reduce the number of components such as the circuit board.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a small contactless transmission device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of the small contactless transmission device of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Small non-contact transmission apparatus 20 Receiving part 30 Transmitting part 1, 2, 6, 7 Coil 3 Resonant capacitor 4 Rectifier / detection diode 5 Smoothing capacitor 8 Resonant capacitor 11 External connection terminal part 21 Ferrite core 23 Wiring pattern 22 Insulator 23a, 23b, 23c, 23d Coil connection part 23e, 23f Resonance capacitor connection part 23g, 23h Diode connection part 23i, 23j Smoothing capacitor connection part 23k, 231 External terminal part 23 'Wiring 31 Ferrite core 33 Wiring pattern 32 Insulator 33a, 33b, 33c, 33d Coil connection part 33e, 33f Resonance capacitor connection part 33g, 33h External connection terminal part

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H02J 17/00 H01F 1/34 A

Claims (13)

[Claims] The present invention includes a coil which is opposed to each other via an air gap, one of which is an input side or a transmission side, and the other is an output side or a reception side. A non-contact type transmission device for transmitting electric power, wherein the coils are respectively arranged on ferrite cores as a base material of a substrate provided with a wiring pattern. 2. A small-sized non-contact transmission device according to claim 1, wherein said opposed coils are formed of a plane meander type coil or a plane spiral type coil, and each of them is at least one. Small contactless transmission device. 3. The compact non-contact transmission device according to claim 1, wherein the ferrite core has a high electric resistance.
A compact non-contact transmission device comprising a Ni-based ferrite comprising an i-Zn-based or Ni-Zn-Cu-based ferrite, wherein the ferrite core is used as a base material of the substrate. 4. The compact non-contact transmission device according to claim 1, wherein the ferrite core is made of a Mn—Zn-based ferrite having a high magnetic flux saturation density, and the ferrite core is used as a base material of the substrate. A small non-contact transmission device comprising an insulator interposed between the ferrite core and the wiring pattern for green. 5. The compact non-contact transmission device according to claim 1, wherein the wiring pattern includes a connection portion for mounting an input side coil and a resonance capacitor on an input side. A small non-contact transmission device comprising an external connection terminal portion, and an output side having a connection portion for mounting an output side coil, a resonance capacitor, a rectifier diode, and a smoothing capacitor, respectively, and an external connection terminal portion. . 6. The compact non-contact transmission device according to any one of claims 1 to 5, wherein the ferrite core comprises:
When made of Ni-Zn ferrite, electric resistance (ρ)
Is not less than 10 kΩ · m, and is 1 MΩ · m or more when made of Ni—Zn—Cu-based ferrite, the saturation magnetic flux density (B) is 300 mT or more, and the magnetic permeability (μ) is 500
As described above, when made of Mn-Zn ferrite,
The electric resistance (ρ) is 5 Ω · m or more, the saturation magnetic flux density (B) is 500 mT or more, and the magnetic permeability (μ) is 200
A small non-contact transmission device characterized by being 0 or more. 7. The compact non-contact transmission device according to claim 1, wherein the ferrite core comprises:
A compact non-contact transmission device comprising a Ni-based ferrite selected from the group consisting of Ni-Zn-based and Ni-Zn-Cu-based ferrite, wherein a frequency used for transmission is 200 kHz or more. 8. The compact non-contact transmission device according to any one of claims 1 to 6, wherein the ferrite core comprises:
A compact non-contact transmission device comprising a Mn-Zn ferrite, wherein a frequency used for transmission is 200 kHz or less. 9. The small non-contact transmission device according to claim 1, wherein the thickness of the ferrite core is in a range of 0.1 to 5 mm. Transmission equipment. 10. The small-sized non-contact transmission device according to claim 1, wherein a contactless transmission system is eliminated. 11. The compact non-contact transmission device according to claim 1, wherein each of the ferrite cores includes an electric circuit including a coil on one surface, and is mounted on an outer portion of the electric circuit. And a leakage magnetic flux generated from the electric circuit is suppressed to 40% or less. 12. The compact non-contact transmission device according to any one of claims 1 to 11, wherein the output side or the reception side coil is formed on one side of a ferrite core on the other side opposite to the one side. It is characterized in that the charging member is provided through a gap of 0 to 2 mm, or that the ferrite core can be separated from at least the charging member and the ferrite core in the charging member and the electric circuit. Small non-contact transmission device. 13. The compact non-contact transmission device according to any one of claims 1 to 12, wherein a gap, which is an interval between the coils, is 0 to 5 mm (however, 0 is not included). Small contactless transmission device.