JP2002017046A - Noncontact battery charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a noncontact battery charger which enables the weight reduction and the thickness reduction. SOLUTION: The 1st coil 1 and 3rd coil 6 of this noncontact charger are hollow coils whose one side winding surfaces face each other. The coil 2 of the 2nd coil 2 of the charger is a printed coil printed spirally and faces the other side surface of the 1st coil and is, further, arranged at an approximately same position as the center axis of the 1st coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cordless telephone,
The present invention relates to a non-contact charger which can charge a rechargeable battery used as a power source of a portable device or the like in a non-contact manner without using a metal contact by electromagnetic induction.

[0002]

2. Description of the Related Art In recent years, non-contact type chargers utilizing electromagnetic induction have been required to be not only smaller but also thinner and lighter in electronic devices, particularly portable electronic devices and cordless telephones.

Conventionally, non-contact type chargers utilizing electromagnetic induction include those using a separately-excited oscillation circuit. The separately-excited oscillation circuit has a special type of oscillation circuit that is controlled and driven by a switching element. A circuit is required, which not only complicates the circuit, but also degrades efficiency due to power consumption of the control circuit. Further, since the number of parts increases, the product price increases, and miniaturization and weight reduction cannot be achieved.

In recent years, as a circuit system having a simple circuit configuration and low power consumption, Japanese Patent Laid-Open No.
95284, JP-A-6-225528, JP-A-9-12
1481 has been published.

FIG. 3 shows a circuit diagram of one of the non-contact chargers using a resonance type class C self-excited oscillation circuit. The charging unit 9 connects the resonance capacitor C1 in parallel with the power transmission coil T1, and causes the field effect transistor Q1 to perform switching operation of the DC input from the positive electrode 9a and the negative electrode 9b of the DC input terminals. An oscillation feedback coil T2 is arranged to continuously perform switching operation and continue oscillation, and a bias capacitor C2 is connected to one end of the coil.
It is necessary to improve the power efficiency and to perform the class C operation reliably. Therefore, the resistors R2, R3
And the connection point between R2 and R3 and the oscillation feedback coil T2
A diode D1 is connected between one ends of the two. Charged part 1
Reference numeral 0 denotes charging the rechargeable battery B in a configuration in which a diode D11 is connected in series to the power receiving coil T3 and a capacitor C11 and a capacitor C12 are connected in parallel, and a constant current circuit is added.

As described above, the circuit configuration of the charging section and the charged section is simple, and the number of components is small, so that it is suitable for miniaturization and weight reduction. Next, the structure of the coil component used in the contactless charger is shown in FIGS.

FIG. 4 is a sectional view of an example of a conventional contactless charger. The charging unit inserts a bobbin-less coil 13 made of a cement wire or the like into a terminal block 14 having a non-flanged winding frame 14a as a first coil, which is a power transmission coil T1, and attaches the T-shaped core 12 to the terminal block 14. Inserted and fixed. Next, a substrate 15 for a high-frequency oscillation circuit is attached to the terminal block 14, and the lead of the first coil T1 is connected to the substrate 15 constituting the oscillation circuit. As shown in FIG. 5, the high-frequency oscillation circuit substrate 15 has a second surface for oscillation feedback on the surface 15a.
The coil (T2) 16 is formed in a spiral shape by printing, and an oscillation circuit is formed on the back surface 15b. Since the core 12 exists between the first coil and the second coil for oscillation feedback, magnetic shielding is provided, and the coupling between the first coil and the second coil is weak. The charged part is a third coil, which is the power receiving coil T3, connected to the terminal block 2 having the non-flanged winding frame 20a.
The bobbin-less coil 19 made of cement wire or the like is inserted into the winding frame portion of No. 0. 18a is a housing on the power transmission side, and 18b is a housing on the power reception side.

[0008]

As described above, in the charging section, the first coil, which is the power transmission coil T1, is heavy due to the use of the T-shaped core and is fixed using the terminal block. It is getting thicker. And
The portion to be charged is also thick in the third coil, which is the power receiving coil T3, because it is fixed to the terminal block. An object of the present invention is to provide a non-contact charger suitable for weight reduction and thickness reduction by omitting these cores and terminal blocks.

[0009]

In order to achieve the above object, the present invention separates a charging section and a charged section, and the charging section includes a first coil for power transmission and a feedback winding for oscillation. A non-contact charger comprising a high-frequency oscillation circuit having a second coil and a charged part including a third coil for receiving power, wherein the first coil and the third coil are air-core coils Wherein the winding surfaces face each other, and the second coil is a printed coil printed in a spiral shape, and faces the other winding surface of the first coil via the substrate. A contactless battery charger is provided.

Further, in the present invention, the first coil and the second coil are arranged so that the winding surfaces of the first coil and the second coil are opposed to each other and the central axes thereof are substantially the same, with the circuit board interposed therebetween. The above object can be reliably achieved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention separates a charging section and a charged section, and the charging section comprises a high frequency oscillation circuit having a first coil for power transmission and a second coil which is an oscillation feedback winding. In the non-contact charger, wherein the charged portion includes a third coil for receiving electric power, the first coil and the third coil are air-core coils, and the winding surfaces thereof are arranged via a substrate. The second coil is a printed coil printed in a spiral shape, and has a configuration facing the other winding surface of the first coil. By directly attaching the air-core coil and the printed coil printed on the substrate or the air-core coil to the substrate in this manner, the terminal block can be omitted, and the thickness and weight can be reduced.

Further, the first coil and the second coil are arranged so that the winding surfaces of the first coil and the second coil are opposed to each other and the central axes thereof are substantially the same with each other with the circuit board interposed therebetween.
Magnetic coupling and insulation between the second coil and the second coil,
It can be made thinner and lighter.

[0013]

Next, the present invention will be described by way of examples. FIG. 1 is a sectional view of the contactless charger of the present invention. FIG.
Is a high-frequency oscillation circuit board constituting the non-contact charger of the present invention. The charging circuit used in the present invention is the same as the conventional one.
4 is a self-excited oscillation circuit of FIG. In the charging section, the first coil 1, which is the power transmission coil T1, is wound around the upper surface 3a of the circuit board 3 with a cement wire, and an air-core coil to which the winding is fixed is placed at a predetermined position with an adhesive. And so on. The second coil 2, which is the oscillation feedback coil T2, is a printed coil spirally printed on the back surface 3b of the circuit board 3 and forms an oscillation circuit. First
The coil 1 and the second coil 2 have an air-core coil having no core and a printed coil opposed to each other with the circuit board 3 interposed therebetween, thereby enhancing magnetic coupling. The other circuit electronic component 4 of the charging unit is arranged on the front surface 3a of the circuit board. In the portion to be charged, the third coil 6, which is the power receiving coil T3, is wound around a substrate with a cement wire, and an air-core coil to which the winding is fixed is attached to a predetermined position with an adhesive or the like. 8
Reference numerals a and 8b denote respective portions of the housing of the charging section and the charged section.

[0014]

As described above, in the non-contact charger of the present invention, the first coil of the charging section and the third coil of the section to be charged are formed by air-core coils, and the oscillation feedback winding of the charging section is used. A certain second
By using a coil as a printed coil, a conventionally used core can be omitted and the weight can be reduced, and by directly attaching an air-core coil to a circuit board, the thickness can be reduced without providing a coil terminal block or the like. . Furthermore, the first
By arranging the first coil and the second coil such that the winding surfaces of the first coil and the second coil are opposed to each other with the circuit board interposed therebetween and the center axes thereof are substantially the same, the magnetic force of the first coil and the second coil is increased. As a result, a secure connection and insulation can be ensured, and the thickness and weight can be reduced. By using an air-core coil without a core and a terminal block, the number of parts can be reduced and the product price can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a contactless charger of the present invention.

FIG. 2 is a circuit board constituting the non-contact charger of the present invention.

FIG. 3 is a circuit diagram showing one embodiment of a non-contact charger used in the present invention.

FIG. 4 is a cross-sectional view of a contactless charger showing one embodiment of the related art.

FIG. 5 is a circuit board constituting a non-contact charger according to one embodiment of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st coil 2 2nd coil 3 Charge part circuit board 4 Electronic component for circuits 6 Third coil 7 Charge part board 8a Charge part case 8b Charge part case

Claims (2)

[Claims] A charging section is separated from a charging section, and the charging section includes a high-frequency oscillation circuit having a first coil for power transmission and a second coil serving as an oscillation feedback winding. A charging unit including a third coil for receiving electric power, wherein the first coil and the third coil are air-core coils, and winding surfaces thereof face each other; The second
The non-contact charger is a printed coil which is printed in a spiral shape and faces the other winding surface of the first coil. 2. The method according to claim 1, wherein the first coil and the second coil are arranged so that the winding surfaces of the first coil and the second coil oppose each other and the central axes thereof are substantially the same. 1
The contactless charger as described.