JP2002353726A - Small-sized antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized antenna with a stable characteristic that can be mounted on an electronic device without the need for using a printed circuit board. SOLUTION: An antenna element 12 having; a feeding section 12a; and a ground section 12b and a ground plate 14 are integrally formed from one metallic plate so that the ground section 12b and the ground plate 14 are formed consecutive. A groove 18 to position the end of a center conductor 16a of the feeding section 12a is formed to the feeding section 12a of the antenna element. A contact piece 20 in contact with an outer conductor 16b of a feeder and a support piece 22 supporting the feeder 16 are formed to the ground plate 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[Detailed description of the invention] The present invention relates to a small antenna incorporated in an electronic device.

[0002]

2. Description of the Related Art Conventionally, as a small antenna, a chip antenna in which an antenna element is formed on a dielectric chip is widely known. The chip antenna is mounted on an electronic device while being mounted on a printed circuit board having a feed line and a ground plate.

[0003]

The chip antenna needs to use a printed circuit board to be incorporated in an electronic device. For example, if the circuit that processes the input / output signals of the antenna cannot be placed near the antenna due to space or the like, the antenna and the signal processing circuit are placed apart, and both are connected by a feeder line. Even in such a case, the chip antenna is mounted on a printed circuit board different from the signal processing circuit, and is incorporated into the electronic device with the power supply line connected to the power supply line of the printed circuit board.

[0004] As described above, the chip antenna has the inconvenience that a printed circuit board must be used to incorporate it into an electronic device. In addition, the use of a printed circuit board causes an increase in cost. Further, when the chip antenna is mounted on a printed circuit board, there is a problem that even if the positional relationship with the ground plate of the printed circuit board is shifted even a little, the antenna characteristics are changed.

In view of the above problems, an object of the present invention is to provide a small antenna that can be incorporated into an electronic device without using a printed circuit board, is low in cost, and has stable characteristics. It is in.

[0006]

Means for Solving the Problems In order to achieve this object, a small antenna according to the present invention comprises an antenna element having a feeding unit and a grounding unit, and a ground plate formed of a single metal plate. Are formed integrally so as to be continuous. This way,
Since small antennas can be mass-produced by punching a metal plate, cost can be reduced.Because the antenna element and the ground plate are integrated, the positional relationship between them is stable, and stable characteristics are obtained. It can be incorporated into electronic equipment without using a printed circuit board.

In the small antenna according to the present invention, the positioning portion for positioning the end portion of the center conductor of the feed line at a predetermined position is formed in the feeding portion of the antenna element, so that the displacement of the center conductor can be reduced. It is preferable in order to eliminate and stabilize the characteristics.

In the small antenna according to the present invention, the ground plate is provided with a contact piece that is in contact with the external conductor of the feed line by cutting and raising a part of the ground plate, thereby facilitating attachment and grounding of the feed line. It is preferable to perform the above.

Further, in the small antenna of the present invention, the ground plate is formed with a holding piece for holding the power supply line at a predetermined position by cutting and raising a part of the ground plate. It is preferable in performing.

[0010]

Hereinafter, embodiments of the present invention will be described.
This will be described in detail with reference to the drawings.

Embodiment 1 FIG. 1 shows an embodiment of the present invention. This small antenna 10 has an antenna element
12 and the ground plate 14 are integrally formed by punching a single metal plate. The antenna element 12 has a feeding part 12a and a ground part 12b, and the ground part 12b is formed so as to be continuous with the ground plate 14. As the metal plate, a copper or copper alloy plate, a steel plate subjected to solderable plating (copper plating, nickel plating, or the like) can be used. The thickness of the metal plate may be such that it can hold its shape by itself in the state formed as shown in FIG.

The feeding section 12 a of the antenna element 12 is L
As shown in FIG. 1 (B), a groove 18 for positioning the end of the center conductor 16a of the feeder line 16 at a predetermined position is formed at the tip end thereof. The center conductor 16a is a groove
While being positioned at 18, it is fixed to the power supply section 12a by soldering (solder is not shown).

The ground plate 14 includes a contact piece 20 for contacting an outer conductor (shield layer) 16 b of the power supply line 16,
A holding piece 22 for holding 16 at a predetermined position is integrally formed by cutting and raising. At four corners of the ground plate 14, mounting holes 24 are formed. This mounting hole 24
Is for directly attaching the small antenna 10 to a case or the like of an electronic device. The position of the mounting hole 24 may be a position other than the four corners. The device may be attached to a case or the like by means other than the attachment holes.

With the above configuration, the ground portion 12 b of the antenna element 12 is integrated with the ground plate 14, and the feed portion 12 a of the antenna element 12 is located at the center of the feed line 16 fixed to the ground plate 14. Since it is integrated with the conductor 16a, the positional relationship between the antenna element 12 and the ground plate 14 is extremely stable. Also, the center conductor 16a of the feed line 16
Is positioned by the groove 18 formed in the power supply section 12a, so that there is no displacement between the center conductor 16a and the power supply section 12a. Therefore, a small antenna with stable characteristics can be obtained. Further, since the small antenna 10 can be mass-produced by stamping a metal plate, the cost can be reduced. Further, it can be incorporated into an electronic device without using a printed circuit board.

Embodiment 2 FIG. 2 shows another embodiment of the present invention. In this embodiment, a positioning hole 26 is formed in the feeding portion 12a of the antenna element, and the center conductor 16a of the feeding line is inserted into the hole 26 to position the center conductor 16a. Otherwise, the configuration is the same as that of the embodiment of FIG.

Embodiment 3 FIG. 3 shows still another embodiment of the present invention. In this small antenna 10, the antenna element 12 is bent at the ground portion 12b, and the antenna element 12 is inclined with respect to the ground plate 14. By doing so, it is possible to adjust the directivity and frequency characteristics of the antenna by the inclination angle of the antenna element 12. The other configuration is the same as that of the embodiment of FIG. 1, and therefore, the same portions are denoted by the same reference numerals and description thereof will be omitted.

[0017]

As described above, the small antenna according to the present invention can be mass-produced by punching a metal plate, so that the cost is low. Further, since the antenna element and the ground plate are integrally formed, the positional relationship between the two is reduced. Is stable,
Stable characteristics can be obtained, and it can be incorporated in electronic equipment without using a printed circuit board.

[Brief description of the drawings]

1A and 1B show an embodiment of the present invention, wherein FIG. 1A is a plan view, FIG. 1B is a cross-sectional view taken along the line BB of FIG. 1A, and FIG.
(D) is a cross-sectional view taken along a line DD in FIG.

FIG. 2 is a plan view of a main part showing another embodiment of the present invention.

FIG. 3 is a perspective view showing still another embodiment of the present invention.

[Explanation of symbols]

 10: Small antenna 12: Antenna element 12a: Feeding part 12b: Grounding part 14: Ground plate 16: Feeding line 16a: Central conductor 16b: External conductor 18: Positioning groove 20: Contact piece 22: Holding piece 24: Mounting hole 26: Positioning hole

Claims (4)

[Claims] 1. A small antenna comprising: an antenna element having a feeding portion and a ground portion; and a ground plate, which are integrally formed of a single metal plate so that the ground portion and the ground plate are continuous. 2. The small antenna according to claim 1, wherein a positioning portion for positioning an end of the center conductor of the feeding line at a predetermined position is formed at a feeding portion of the antenna element. 3. The small antenna according to claim 1, wherein the ground plate has a contact piece that is in contact with the outer conductor of the feeder line by cutting and raising a part of the ground plate. 4. The ground plate according to claim 1, wherein a holding piece for holding the power supply line at a predetermined position is formed by cutting and raising a part of the ground plate. Small antenna.