JPH0969453A - Power supply - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a transfer of high power possible by a very low-cost method and low in the non-contact power supply of a small-sized electronic device. SOLUTION: In a non-contact power supply device of a structure, wherein a primary coil 4a, which is fed a high-frequency current, is made to oppose to a secondary coil 8a mounted in a case different from that for the coil 4a and power is transferred from the coil 4a to the coil 8a, the surface, which opposes to the coil 8a, of the coil 4a is formed into a flat surface, an I-type primary core 1a is provided in the center of the coil 4a and the coil 8a is provided with an E-type secondary core 5a. Thereby, a miniaturization of a device is made possible and moreover, the non-contact power supply, which is good in efficiency and is high in reliability, is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type power supply device for a small portable device such as a cordless phone, a mobile phone, a PHS, a movie, a personal computer or the like.

[0002]

2. Description of the Related Art A non-contact type power supply device transfers electric power from a primary side to a secondary side, and the primary side circuit and the secondary side circuit are mounted in separate independent housings. Therefore, magnetic coupling between the primary coil and the secondary coil is extremely important for efficiently transmitting electric power. As a means for improving this magnetic coupling, it is considered that the configuration of the EE core is effective. Further, it has been common to widen the facing area between the primary winding and the secondary winding to improve magnetic coupling.

Details of the above conventional technique will be described with reference to FIGS. FIG. 3 shows E as a primary core 1 and a secondary core 5.
This is a configuration using a mold core. A primary winding 2 is wound around the groove of the primary core (E-shaped core) 1 to form a primary coil 4. Similarly, the secondary winding 6 is wound around the groove portion of the secondary core (E-shaped core) 5 to form the secondary coil 8.

Next, the operation will be described. When a high-frequency current is passed through the primary winding 2 wound concentrically, the primary winding 2
And a magnetic flux is generated in the primary core 1. This magnetic flux is transmitted to the secondary core 5 and the secondary winding 6, converted into electric power, and supplied to the load.

Further, FIG. 4 shows an attempt to widen the facing area between the primary winding 2 and the secondary winding 6 to improve the magnetic coupling between the windings.

[0006]

In the conventional configuration as shown in FIG. 3 as described above, the magnetic circuit is an open magnetic circuit, so that the primary core (E-shaped core) 1 comes out from the middle leg 9. The magnetic flux is returned to the outer leg 10, and the magnetic flux is short-circuited. Therefore,
The magnetic flux transmitted to the secondary side was reduced, which was a factor that the efficiency did not increase.

FIG. 4 shows a case in which the facing area of both coils is wide.
The shape of the product, including the housing, is extremely large on both the primary side and the secondary side, which has been an obstacle to the miniaturization of equipment.
Accordingly, the present invention eliminates the above-mentioned conventional drawbacks, and provides a power supply device which is simple in structure, has a high power transfer rate, can be miniaturized, and is inexpensive and highly reliable.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a primary coil supplied with a high frequency current and a secondary coil mounted in a housing different from the primary coil face each other. In the non-contact power supply device that transmits electric power from the primary coil to the secondary coil, a surface where the primary coil and the secondary coil face each other is flattened, and an I-shaped primary core is provided in the center of the primary coil. The secondary coil is provided with an E-shaped secondary core.

[0009]

With the above structure, it is possible to downsize the device,
Moreover, it is possible to realize a highly reliable non-contact type power supply device that is highly efficient and can take out a larger output power.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the power supply device of the present invention is shown in FIG.
This will be described with reference to FIG. In FIG. 1, a primary core 1a is provided as an I-shaped core in the center of the primary bobbin 3a, and a primary winding 2a is wound around the I-shaped core 1a to form a primary coil 4a. Similarly, an E-shaped secondary core 5a is provided in the center of the secondary bobbin 7a, and a secondary winding 6a is wound between the middle leg and the outer leg of the secondary core 5a to form a secondary coil. 8a.

The operation will be described below. When a high-frequency current is passed through the primary winding 2a wound concentrically, magnetic flux is generated in the primary winding 2a and the primary core 1a provided in the central portion of the primary winding 2a. In the conventional example, since the E-type core was used for the primary coil, there was a short circuit of magnetic flux between the middle leg and the outer leg of the E-type core. However, when the I-type core of the present invention is used as the primary core 1a There is no short circuit of magnetic flux at. Also, the magnetic flux emitted from one side cross section of the primary core 1a draws a large loop,
It passes through the secondary coil 8a and returns to the other cross section of the primary core 1a. That is, by using the I-shaped core for the primary core 1a, the magnetic flux easily passes through the secondary coil 8a. Further, in order to concentrate and release this magnetic flux in the central portion, it is extremely effective to use the I-shaped core as the primary core 1a.

Since the magnetic circuit has an open magnetic circuit, magnetic flux is emitted from the primary coil 4a in multiple directions. In order to improve efficiency, it is necessary to collect more magnetic flux, and it is important that the opposing secondary coils 8a be magnetically coupled in a wide range.
For a, it is useful to use an E-type core as a secondary core.

[0013]

As described above, according to the present invention, the I-type primary core is provided in the center of the primary coil, and the E-type secondary core is provided in the secondary coil. In addition, it is possible to mount a highly reliable non-contact type power supply device capable of achieving high efficiency and capable of extracting a larger output power.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a primary coil and a secondary coil, which are essential parts of an embodiment of a power supply device of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a sectional view of a primary coil and a secondary coil, which are main parts of a conventional power supply device.

FIG. 4 is a primary coil that is a main part of another conventional power supply device;
Cross section of secondary coil

[Explanation of symbols]

 1a primary core 2a primary winding 4a primary coil 5a secondary core 6a secondary winding 8a secondary coil 9 primary core middle leg 10 primary core outer leg

Claims (1)

[Claims] 1. A primary coil to which at least a high-frequency current is supplied and a secondary coil mounted in a housing different from the primary coil face each other, and power is transmitted from the primary coil to the secondary coil. In the non-contact power supply device, the surfaces of the primary coil and the secondary coil facing each other are flattened, an I-shaped primary core is provided in the center of the primary coil, and an E-shaped secondary core is provided in the secondary coil. A power supply device characterized by being provided.