JP2003086427A - Air-core coil for high-frequency circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-core coil for high-frequency circuit which is suitable for physically thinner circuit and assures easy adjustment of the circuit. SOLUTION: The air-core coil for high-frequency circuit comprises a winding portion 4, which is formed by winding two conductor wires 2, 3 in parallel and connecting portions 5a, 5b provided at the end part of the winding portion 4. Since two conductor wires 2, 3 are wound with each other under the parallel condition to a center line C1 of the winding portion 4 and have the connecting portions 5a, 5b where two conductor wires 2, 3 located at the end part are connected, the air-core coil 1 is formed of a bifilar wire and diameter A1 of the conductor wires 2, 3 can be set narrower than a diameter A2 of a conventional conductor wire 22. Therefore, height of the winding portion 4 of the air-core coil 1 can be set smaller than the conventional one from the surface of a printed circuit board 6. Accordingly, the air-core coil for high-frequency circuit which is desirably applied to the physically thin circuit can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency circuit air-core coil suitable for use in an oscillation circuit, a tuning circuit, etc. of a television tuner.

[0002]

2. Description of the Related Art A conventional air core coil for a high frequency circuit will be described with reference to FIG. 3. For example, an air core coil 21 used for a high frequency circuit of an oscillator circuit has a relatively thick wire diameter S.
A single conducting wire 22 of 2 is used, and has a winding portion 23 wound a plurality of times and connecting portions 24a and 24b provided at both ends of the winding portion 23.

The air-core coil 21 thus formed has a center line C of the winding portion 23, as shown in FIG.
2, the conductor wire 22 is wound in a parallel state to form a winding portion 23, and the winding portion 23 has a diameter Z2 (a length up to the center A2 of the conductor wire 22) centered on the center line C2. It has been wound around.

In the air-core coil 21 having such a structure, the conductive patterns 26a, 26 provided on the printed circuit board 25 having the connecting portions 24a, 24b forming a circuit board.
Each of them is placed on b and is connected to the conductive patterns 26a and 26b by soldering.

The air-core coil 21 having a large wire diameter A2 is used in order to obtain a high oscillation frequency of the oscillation circuit, thereby reducing the inductance. Therefore, the thick wire diameter A2 is used. When the conducting wire 22 is used, the air-core coil 21 from the surface of the printed circuit board 25
It was not suitable for products that required a thin shape because of its large height.

The air-core coil 21 mounted on the printed circuit board 25 adjusts the frequency by displacing the winding portions 23 in the arrow Y2 direction and changing the interval between the winding portions 23. However, if the conductor wire 22 with a thick wire diameter A2 is used, its own spring property (returning force at the time of displacement)
Becomes large and the winding portion 23 is slightly displaced in the direction of the arrow Y2, the displaced portion returns to its original state, and its adjustment work is difficult and troublesome.

[0007]

In the conventional air-core coil for high frequency circuits, for example, in order to obtain a high oscillation frequency of the oscillation circuit, a wire having a thick wire diameter A2 is used to reduce the inductance. The use of the conductive wire 22 having the thick wire diameter A2 increases the height of the air-core coil 21 from the surface of the printed circuit board 25, which is not suitable for thinning. Further, when the conductive wire 22 having the thick wire diameter A2 is used, the spring property of itself (returning force at the time of displacement) becomes large, and when the winding portion 23 is slightly displaced in the arrow Y2 direction, the displacement is caused. There is a problem that the part returns to the original state and the adjustment work is difficult and troublesome.

Therefore, an object of the present invention is to provide an air core coil for a high frequency circuit, which is suitable for a thin type and whose adjustment work is easy.

[0009]

As a first solving means for solving the above-mentioned problems, a winding portion around which two conducting wires arranged in parallel are wound and an end portion of the winding portion is provided. And a connecting portion, wherein the two conducting wires are wound in parallel with each other in a state parallel to the center line of the winding portion, and the two conducting wires located at end portions of each other are connected to each other. It is configured to have a part.

As a second solving means, the two conducting wires are wound in a state of being in close contact with each other. As a third means for solving the problems, the connecting portions of the two conductors are connected to the conductive pattern in a state where they are juxtaposed on the conductor pattern provided on the printed board.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A drawing of the air-core coil for a high-frequency circuit of the present invention will be described. FIG. 1 relates to the air-core coil for a high-frequency circuit of the present invention, and is a side view showing a state in which the air-core coil is attached to a printed circuit board. FIG. 2 and FIG. 2 relate to the air-core coil for a high frequency circuit of the present invention, and are explanatory views showing the relationship between the air-core coil of the present invention and the conventional air-core coil.

Next, the structure of the air-core coil for a high-frequency circuit of the present invention will be described with reference to FIGS. 1 and 2. For example, the air-core coil 1 used for a high frequency circuit of an oscillation circuit is relatively thin. A bifilar wire is used, which is arranged in a state in which two conductor wires 2 and 3 having a wire diameter S1 are closely attached to each other.
Has a winding part 4 that is wound a plurality of times in parallel, and connection parts 5a and 5b that are provided at both ends of the winding part 4 and that connect two conductors 2 and 3 to each other. . In addition, the two conductors 2 and 3 have an insulating coating (not shown) applied to the portions other than the connection portions 5a and 5b, and the two conductors 2 and 3 respectively.
Is formed to have a diameter of about 1/2 of the diameter of the conventional conductive wire 22.

The air-core coil 1 thus formed has a center line C of the winding portion 4 as shown in FIG.
The two conducting wires 2 and 3 are parallel to each other and wound in a closely contacted state to form a winding portion 4, and the winding portion 4 has a center line C.
It is configured such that it is wound with a diameter Z1 (a length up to the center A1 of the conductive wires 2 and 3) with 1 being the center. That is, the diameter Z1 of the air-core coil 1 of the present invention is formed to be equal to the diameter Z2 of the conventional air-core coil 21, and therefore the present invention and the conventional air-core coil have the same total length. There is.

In the air-core coil 1 of the present invention having such a configuration, the connecting portions 5a and 5b are respectively placed on the conductive patterns 7a and 7b provided on the printed circuit board 6 forming the circuit board, It is configured to be connected to the conductive patterns 7a and 7b, respectively, by soldering.

If the air-core coil 1 made of a bifilar wire is used as in the present invention, for example, in order to obtain a high oscillation frequency of the oscillation circuit, a thin wire diameter A2 is not used and a thin wire is used. Since the wire diameter is A1, the inductance can be reduced. Therefore, as shown in FIG. 2, the height of the winding portion 4 of the air-core coil 1 can be made smaller than that of the conventional one from the surface of the printed circuit board 6 and is suitable for those required to be thin. Becomes

Further, in the air-core coil 1 mounted on the printed circuit board 6, the winding portion 4 is displaced in the arrow Y1 direction,
The frequency is adjusted by changing the interval between the winding portions 4, but since the conductive wires 2 and 3 having a small wire diameter A1 are used, the spring property of itself (returning force at the time of displacement) is obtained.
Is smaller than the conventional one, and even when the winding part 4 is slightly displaced in the direction of the arrow Y1, it is deformed to the displaced position,
The adjustment work becomes easy.

Further, the connecting portions 5a, 5b of the air core coil 1
Is placed on the conductive patterns 7a and 7b in a state where the two conductors 2 and 3 are juxtaposed in parallel with the center line C1, and in this state, the connecting portions 5a and 5b are electrically conductive. When soldered to the patterns 7a and 7b, the solder also intrudes between the two conductors 2 and 3 to ensure the connection.

In the above embodiment, the conductors 2 and 3 have been described as having a wire diameter of about 1/2 of the conventional conductor wire, but a wire diameter smaller than 1/2 of the conventional wire diameter is used. You may use it.

[0019]

The air-core coil for a high-frequency circuit according to the present invention has a winding portion 4 around which two conducting wires 2 and 3 arranged in parallel are wound, and a connection provided at an end portion of the winding portion 4. The two conductors 2 and 3 provided with the portions 5a and 5b are wound in parallel with each other in a state parallel to the center line C1 of the winding portion 4, and the two conductors 2 and 3 located at the ends of each other. Connection parts 5a, 5b in which the two are connected to each other
Since the air core coil 1 has a bifilar wire, the wire diameter A1 of the conductor wires 2 and 3 can be made smaller than the wire diameter A2 of the conventional conductor wire 22. The height of 4 can be made smaller than that of the conventional one from the surface of the printed circuit board 6, and it is possible to provide an air-core coil for a high-frequency circuit, which is suitable for a thin type. Also, the wire diameter S of the conductors 2 and 3
Since 1 can be made thin, the spring property of itself (returning force at the time of displacement) is smaller than that of the conventional one, and even when the winding part 4 is slightly displaced in the direction of the arrow Y1, it is deformed to the displaced position. , The adjustment work becomes easy.

Further, since the two conductors 2 and 3 are wound in a state in which they are in close contact with each other, it is possible to provide the air-core coil 1 having a small variation in the inductance and the air-core coil for a high-frequency circuit having a small deformation with time. .

Further, the connecting portions 5a, 5 of the two conducting wires 2, 3
b is a conductor pattern 7a provided on the printed circuit board 6,
Since the conductive patterns 7a and 7b are connected to each other in a state of being juxtaposed on the conductive pattern 7b, the connecting portions 5a and 5b have the conductive patterns 7a and 7b.
When soldered to a and 7b respectively, two conductors 2,
Solder also intrudes into the space between the three, and a reliable connection can be obtained.

[Brief description of drawings]

FIG. 1 is a side view of an air-core coil for a high-frequency circuit according to the present invention, showing a state in which the air-core coil is attached to a printed circuit board.

FIG. 2 is an explanatory diagram showing a relationship between the air-core coil of the present invention and a conventional air-core coil according to the air-core coil for a high frequency circuit of the present invention.

FIG. 3 is a side view of a conventional air-core coil for a high-frequency circuit, showing a state in which the air-core coil is attached to a printed circuit board.

[Explanation of symbols]

1 air core coil 2 conductors 3 conductors 4 winding section 5a connection part 5b connection 6 printed circuit boards 7a Conductor pattern 7b conductor pattern C1 center line Z1 diameter A1 center S1 wire diameter

Claims (3)

[Claims] 1. A winding part, which winds two conducting wires arranged in parallel, and a connecting part provided at an end of the winding part, wherein the two conducting wires are the winding part. An air-core coil for a high-frequency circuit, characterized in that the air-core coil is wound around each other in parallel with the center line and has the connecting portion that connects the two conducting wires located at the ends to each other. 2. The air core coil for a high frequency circuit according to claim 1, wherein the two conductive wires are wound in a state of being in close contact with each other. 3. The conductive pattern as claimed in claim 1, wherein the connecting portions of the two conductive wires are connected to the conductive pattern in a state where they are juxtaposed on a conductive wire pattern provided on a printed circuit board. 2. An air core coil for a high frequency circuit according to 2.