JP2003258530A - Chip antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chip antenna of a simple structure that can stably be mounted on a printed circuit board without incurring an inclined mount. <P>SOLUTION: The chip antenna, wherein an antenna conductor comprising a prescribed conductor board is embedded to a dielectric chip of nearly a rectangular solid shape, is provided with a projection of a prescribed height for regulating a mount attitude of the dielectric chip at a lower side of the dielectric chip. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip antenna having a structure in which an antenna conductor made of a predetermined conductor plate is embedded in a dielectric chip.

[0002]

Related Background Art As a small antenna used for a mobile phone, a personal digital assistant, a wireless LAN (local area network) device, etc., the inventors have designed an antenna conductor made of a predetermined conductor plate as a dielectric chip. We proposed a chip antenna with a structure embedded in or laminated on the surface of a dielectric chip. In this type of chip antenna, for example, as shown in the schematic configuration of FIG. 7, an antenna conductor 1 having a so-called meandering line (antenna element) is formed on a dielectric chip 2 having a substantially rectangular parallelepiped shape. It has a structure in which the electrode terminal portion 3 of the antenna conductor 1 which is embedded and led out to the outside from the end portion of the dielectric chip 2 is bent to the lower surface side along the surface of the dielectric chip 2 (for example, Patent Document 1). reference).

[0003]

[Patent Document 1] JP-A-2002-223109 (6
(Page, Figure 8, Figure 9)

[0004]

In the manufacturing process of portable information terminals and the like, mounted components are mounted at high speed on a printed wiring board coated with solder paste by an automatic inserter (chip mounter). At this time, the above-mentioned chip antenna has a structure in which the electrode terminal portion 3 bent in a U-shape is projected on the lower surface side of the dielectric chip 2, and is supported on the printed wiring board by this electrode terminal portion 3. The inventors have found that there is a problem that the mounted chip antenna is tilted due to vibration at the time of mounting and the chip antenna is tilted and easily mounted because it is unstable just by being mounted. When the antenna conductor 1 including the electrode terminal portion 3 is patterned by punching, the punching blade is pressed from a predetermined direction of the conductor plate, so that a punching burr is generated on a specific surface side. For example, in the electrode terminal portion 3 shown in FIG. 7, when the burr is directed to the outer side of the lower surface of the dielectric chip 20 bent in a U shape, when the chip antenna is mounted on the printed board, the burr is printed together with the electrode terminal portion 3. Burrs will be present between the wiring boards. Therefore, there are problems that the chip antenna cannot be stably mounted on the substrate and that soldering becomes unstable.

By the way, when the chip antenna is tilted and mounted, the height position of the antenna conductor (antenna element) from the ground conductor in the printed wiring board or the like on which the chip antenna is mounted changes. It becomes a factor that changes the characteristics. Further, when the chip antenna is attached or detached, there is a concern that the above-mentioned burr of the electrode terminal portion may damage the components mounted around the chip antenna.

The present invention has been made in consideration of such circumstances, and an object thereof is to provide a chip antenna having a simple structure which can be stably mounted on a printed wiring board.

[0007]

In order to achieve the above-mentioned object, a chip antenna according to the present invention is a chip antenna in which an antenna conductor made of a predetermined conductor plate is laminated or embedded in a dielectric chip. The conductor includes an electrode terminal portion that is led out from the end portion of the dielectric chip and is bent to the lower surface side of the dielectric chip, and the dielectric chip projects toward the lower surface side and has a mounting posture of the dielectric chip. It is characterized in that it is provided with a protruding portion having a predetermined height to be regulated.

Preferably, the protrusions are respectively provided on the edges of the dielectric chip where the electrode terminal portion does not exist.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A chip antenna according to an embodiment of the present invention will be described below with reference to the drawings. Figure 1
2 is a perspective view showing a schematic configuration of a chip antenna according to this embodiment, FIG. 2 is a plan view thereof, and FIG. 3 is a view showing a sectional structure thereof. The chip antenna has a size of about 4.4 mm in width, 16 mm in length and 1.2 mm in thickness, and is basically connected to the radiating portion 11 and the end of the radiating portion 11. The antenna conductor 10 includes an electrode terminal portion 12, and a substantially rectangular parallelepiped-shaped dielectric chip 20 in which the radiating portion 11 of the antenna conductor 10 is embedded and the electrode terminal portion 12 is led out to the outside from the end portion. . The dielectric chip 20 is formed, for example, by injection molding a dielectric that is a mixture of synthetic resin and ceramic powder.

By the way, the radiation portion 11 has a thickness of 0.1 mm.
The conductor plate is patterned by punching, etching, or the like, and, for example, as shown in FIG. 2, meandering meandering lines are provided in parallel at a predetermined pitch through a folded portion extending over several turns. In addition, the electrode terminal portion 12
Is a portion extending from the both ends of the radiating portion 11 in the longitudinal direction of the radiating portion 11 over a predetermined length.

As shown in FIGS. 2 and 3, the dielectric chip 20 has the radiating portion 11 embedded in the central portion thereof and the electrode terminal portion 12 from the end face thereof.
To be formed. The electrode terminal portion 12 led out from the end portion of the dielectric chip 20 is bent downward in an L shape (first bending point a) as shown in FIG. 3, and the radiation portion 11 is attached. It is bent inward toward the inside at a position that defines the height (second bending point b) to form a U-shaped leg portion. These bending processes are performed after shaping the dielectric chip 20.

Preferably, when the above-mentioned electrode terminal portion 3 is bent in a U-shape, it is desirable to perform the bending work in two steps. Specifically, the electrode terminal portion 3
Is preferably formed by bending the tip side (second bending point b) of the electrode terminal portion 3 and then bending the dielectric chip 20 side (first bending point a) into a U-shape. By forming in this way, springback can be suppressed and the electrode terminal portion 3 can be formed with high accuracy.

When the radiation portion 11 and the electrode terminal portions 12 located at both ends of the radiation portion 11 are simultaneously patterned by punching, punching burrs are formed on the radiation portion 11 and the electrode terminal portion 12. This punching burr is the mounting surface (soldering surface) of the electrode terminal portion 12 of the chip antenna.
It is desirable that the electrode terminal portion 12 be processed so as to have an inner side surface (side of the dielectric chip 20) bent in a U shape so as not to be located at.

The feature of the chip antenna according to the present invention is that it is projected from the lower surface of the dielectric chip 20 by a predetermined height in the thickness direction thereof as shown in the schematic structure of FIG. The point is that the protrusion 21 is provided. That is, on the mounting surface side of the chip antenna, both edge portions along the longitudinal direction thereof (edge portions where the electrode terminal portion 12 does not exist)
Collar-shaped protrusions 21 are provided in the central portion of each.
Here, the predetermined height means that the height is configured in consideration of the thickness of the electrode of the electrode terminal portion 12 of the antenna conductor 10. Preferably, when the distance between the lower surface of the dielectric chip 20 and the printed wiring board mounting surface side of the U-shaped leg is 0.15 mm, the height of the protrusion 22 is about 0.1 mm. Realized as a thing.

In the dielectric chip 20 having such a structure, for example, a groove (recess) having a predetermined depth for forming the protruding portion 21 is provided on the bottom surface of the dielectric injection molding (molding) mold. The protrusion 21 can be integrally formed. Thus, according to the chip antenna having the above-described structure, since the projecting portion 21 is provided on the lower surface of the dielectric chip 20, when the chip antenna is mounted on the printed wiring board, as shown in FIG. The mounting posture of the (dielectric chip 20) can be regulated.

That is, the supporting attitude of the chip antenna on the printed wiring board can be stably regulated at the four positions of the solder joint surface of the electrode terminal portion 12 and the protruding portion 21. Therefore, it is possible to prevent the chip antenna from tilting or rattling, and it is possible to improve the mounting accuracy of the chip antenna on the printed wiring board. That is, the projecting portion 21 is the radiating portion 1 with respect to the ground conductor of the printed wiring board.
It exhibits the function of accurately defining the height and position of 1.

According to the chip antenna having such a structure, the inclination of the chip antenna during mounting can be prevented. That is, since the stable mounting state can be maintained, it is not necessary to correct the inclination of the chip antenna during the chip mounting process and after the reflow process, and good manufacturing quality can be secured. Even if an external force (stress) is applied to the chip antenna after the chip antenna is mounted on the printed wiring board (after reflow), the two protruding portions 2
Since it is supported at four points by the solder joint surfaces of the one and two electrode terminal portions 12, it is difficult to remove the chip antenna. Further, as a secondary effect, the presence of the protrusions 21 makes it possible to firmly hold the electrode terminal portion 12 by soldering and make it difficult for the electrode terminal portion 12 to be peeled off. Further, even when an external force is applied to the chip antenna from above, the chip antenna is supported at four points, so that the chip antenna is not broken.

When the punching burrs formed on the electrode terminal portion 12 are not bent on the mounting surface (soldering surface) of the electrode terminal portion 12 of the chip antenna, the electrode terminal portion 12 is bent toward the dielectric chip 20 side. When mounting the chip antenna on the printed wiring board, the chip antenna can be stably mounted on the board without any punching burr between the electrode terminal portion 12 and the printed wiring board, and the soldering stability can be improved. It becomes possible to improve. Further, when the chip antenna is attached or detached, it is possible to prevent the components mounted around the chip antenna from being scratched.

The present invention is not limited to the above-described embodiment of the chip antenna in which the antenna conductor is embedded, and may be, for example, a chip antenna having a structure in which the antenna conductor is laminated on the upper surface of the dielectric chip 20. . Further, in addition to the electrode thickness, the height of the protruding portion 21 may be made higher than the electrode thickness in consideration of the floating amount of the chip antenna due to soldering when mounting the chip antenna.
Further, the height of the protruding portion 21 may be set to a desired height in consideration of the board shape, the solder resist thickness, and the like. Alternatively, as shown in FIG. 5 in the second embodiment, the protrusion 21a may be provided over the entire area of the lower surface central portion of the dielectric chip 20. With such a structure, a sufficiently thick dielectric layer can be interposed between the antenna conductor 11 and the conductor, and the antenna can be designed with substantially no air layer. Moreover, it is possible to enhance the regulation of the mounting posture by the protrusion 21a.

The dimensions and the like of each part of the chip antenna may be determined according to the specifications thereof, and the height of the protrusion of the protrusion 21 may be determined by, for example, the thickness of the electrode of the electrode terminal portion 12 and the electrode terminal portion. It is sufficient to set the height to be approximately equal to the floating amount of the chip antenna when soldered on the printed wiring board. Alternatively, as shown in FIG. 6 according to the third embodiment, the structure may be such that the lower surface of the dielectric chip 20 is provided with the projecting portions 21 projecting from the four corners by a predetermined height.

In addition, the present invention can be variously modified and implemented without departing from the scope of the invention.

[0022]

As described above, according to the present invention, since the lower surface of the dielectric chip is provided with the protrusion having a predetermined height in the thickness direction, it is possible to suppress the inclination when the chip antenna is mounted. And so on, a great effect is practically achieved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of a chip antenna according to an embodiment of the present invention.

FIG. 2 is a diagram showing a planar configuration of the chip antenna shown in FIG.

3 is a diagram showing a cross-sectional structure of the chip antenna shown in FIG.

FIG. 4 is a printed wiring board mounting diagram of the chip antenna shown in FIG. 1;

FIG. 5 is a perspective view showing a schematic configuration of a chip antenna according to another embodiment of the present invention.

FIG. 6 is a perspective view showing a schematic configuration of a chip antenna according to another embodiment of the present invention.

FIG. 7 is a perspective view showing a schematic structure of a conventional general chip antenna.

[Explanation of symbols]

1 antenna conductor 2 Dielectric chip 3 electrode terminals 4 printed wiring board 10 antenna conductor 11 Radiator 12 electrode terminals 20 Dielectric chip 21 Projection

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Isao Tomomatsu             2-6-1, Marunouchi, Chiyoda-ku, Tokyo             Kawa Electric Industry Co., Ltd. F-term (reference) 5J046 AA08 AA09 AA19 AB06 QA02

Claims (2)

[Claims] 1. A chip antenna in which an antenna conductor made of a predetermined conductor plate is laminated and embedded in a dielectric chip, wherein the antenna conductor is led out from the end of the dielectric chip and is on the lower surface side of the dielectric chip. 1. A chip antenna, comprising: an electrode terminal portion bent into a rectangular shape; and the dielectric chip having a protrusion of a predetermined height that protrudes to a lower surface side of the dielectric chip and restricts a mounting attitude of the dielectric chip. 2. The chip antenna according to claim 1, wherein the protruding portion is provided at an edge portion of the dielectric chip having no electrode terminal portion.