JPH06290954A - Laminated antenna and manufacture thereof - Google Patents

Abstract

PURPOSE:To realize a laminated antenna which is high in Q value and shortened in manufacturing time by a method wherein magnetic bodies and coil conductors are laminated into a laminate element where a coil conductor is formed in spiral, and laminate elements are stacked up and fixed together into a laminated antenna. CONSTITUTION:Dielectrics 2 and coil conductors 3 are laminated through a screen printing method or a sheeting method and burned into a laminate element 1. The coil conductors 3 are formed into a spiral. A required number of the laminate elements 1 are stacked up, compressed by a pressing machine, and burned at a high temperature into a sintered body. The peripheral surface of the sintered body is polished, if necessary. Connecting conductors 4 and terminals 5 and 6 are provided to the sintered body by baking. By this setup, a laminated antenna high in Q value can be easily manufactured through rather a short manufacturing term.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated antenna used in a radio such as a mobile phone or a transceiver and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional antenna has been constructed by winding a conductor around a ferrite rod. However, this structure is large and the manufacturing process is complicated. As proposed in Japanese Patent Laid-Open No. -65645, a laminated antenna in which a magnetic body such as ferrite and a coil conductor are laminated and sintered has been developed and used.

[0003]

In such a laminated antenna, it is generally known that a high Q can be obtained by increasing the length of the core in the magnetic core direction with respect to the cross-sectional area of the core. ing. However, when such a laminated antenna is manufactured by, for example, a screen printing method, the printing and drying steps need to be repeated a number of times proportional to the number of turns of the coil conductor, which requires a long manufacturing time (for example, tens of turns). Has a number of turns, a thickness of about 1 mm to 3 mm,
That is, when manufacturing a laminated antenna having the length of the core in the magnetic core direction, it takes about one day to repeat printing and drying. ), As a result, there was a problem that the length of the core cannot be made too large.

In view of the above-mentioned circumstances, it is an object of the present invention to provide a laminated antenna and a manufacturing method thereof, which can obtain a high Q value and can shorten the manufacturing time.

[0005]

A laminated antenna according to the present invention constitutes a laminated element body in which a magnetic material and a coil conductor are laminated to form a spiral coil conductor, and a plurality of laminated element bodies are formed. It is characterized in that it is formed by superposing and fixing.

Further, in the method for manufacturing a laminated antenna according to the present invention, a magnetic element and a coil conductor are laminated to form a laminated element body in which a coil conductor is spirally formed, and then a plurality of laminated element bodies are formed. It is characterized by overlapping and fixing.

[0007]

As described above, by stacking the laminated bodies, the core length proportional to the number of laminated laminated bodies can be obtained.

[0008]

1A is a perspective view showing an embodiment of a laminated antenna according to the present invention. The laminated antenna shown in FIG.
A plurality of laminated element bodies 1 shown in the perspective view of (B) are superposed and integrated, and are shown by an equivalent circuit shown in FIG. 1 (C).
The laminated body 1 is manufactured by laminating the dielectric body 2 and the coil conductor 3 by a screen printing method or a sheet method and firing them. The coil conductor 3 has a spiral shape, and the starting end of the coil conductor 3 is formed. The s and the end f are exposed on the side surface of the magnetic body 2. In addition, the laminated body 1 adjacent in the stacking direction
Is electrically connected to the coil end f of the lower laminated element body 1 and the coil start end s of the upper laminated element body 1 by the connection conductor 4 formed by baking or plating, and the lower end of the laminated body is laminated. The conductor 5 serving as one terminal is formed at the coil start end s of the element body 1 in the same manner as described above, and the conductor 6 serving as the other terminal is formed at the coil end f of the laminated element body 1 at the upper end.

FIG. 2 shows an example of a process for manufacturing the laminated body 1 by a screen printing method. In this example,
An example of simultaneously forming four stacked element bodies 1 will be described. First, as shown in (a), a magnetic layer 2a composed of a sheet or layer formed by pasting ferrite powder is prepared. Next, as shown in (b), Ag, Al, Cu, Ag-Pd,
Two linear coil conductor layers 3a are formed by printing from a paste of metal powder such as Pd. These two coil conductor layers 3a are formed by connecting two laminated element bodies 1 to each other, and each coil conductor layer 3a has a starting end s located at the center of the magnetic layer 2a and on the left side, It is formed so as to extend vertically from s along the center and the left side of the magnetic layer 2a and further to the right along the upper and lower sides of the magnetic layer 2a. Next, as shown in (c), a magnetic layer 2b for half the surface is formed so as to cover the coil conductor layer 3a, leaving only both ends (terminations) of the coil conductor layer 3a. Next, as shown in (d), each laminated body, that is, four coil-shaped coil conductor layers 3b having a U-shaped coil conductor layer 3a at the starting end is formed.
Of the magnetic layer 2b is formed so as to overlap with the end of the magnetic layer 2b. Next, as shown in (e), the magnetic layer 2c for the other half surface is formed so as to cover the coil conductor layer 3b, leaving only the end of the coil conductor layer 3b. Next, as shown in (f), four U-shaped coil conductor layers 3c are formed by overlapping the start ends thereof with the end ends of the coil conductor layers 3b that are not covered by the magnetic layer 2b. Next, as shown in (g),
Only the end of the coil conductor layer 3c is left, and the coil conductor layer 3c
A magnetic layer 2d for half the surface is formed so as to cover c. Then, after repeating the steps (d) to (g) for a required number of turns, as shown in (h), after forming the coil conductor layer 3d having the terminations f and f, as shown in (i). Then, the magnetic layer 2e is printed on the entire surface to complete the stacking. As shown in (j), this laminate is cut with a cutter over the width W,
A laminated body having a structure in which the coil starting end s and the terminal end f are exposed on the side surface of the magnetic material is obtained.

A required number of the thus obtained laminated bodies are stacked, pressed and pressed, and sintered at a high temperature to obtain a sintered body. Then, if necessary, the peripheral surface is polished. Then, the connection conductor 4 and the terminals 5 and 6 shown in FIG. 1A are formed by plating or baking. It should be noted that after firing each laminated element body 1, a new glass paste may be applied and fired, or a plurality of laminated element bodies 1 may be integrated with an adhesive.

If the laminated antenna is constructed as described above, a laminated antenna having a length of the laminated body 1 (thickness in the laminating direction) × a core length of the number of laminated bodies 1 can be obtained, and the core length should be increased. Therefore, a laminated antenna having a high Q value can be obtained. Further, in the above-mentioned embodiment, an example in which four laminated element bodies 1 are produced at the same time has been described. However, in practice, it is possible to print 10 or more laminated element bodies 1 at the same time. Thereby, it can be manufactured in a much shorter time than the conventional method. Since the coil conductor 3 is exposed on the side surface of the magnetic body 2 in the present embodiment, it has an open magnetic circuit structure as described in Japanese Patent Publication No. 3-65645 and exhibits an efficient operation. be able to.

FIGS. 3 and 4 show another embodiment of the present invention. As shown in FIG. 4 (a), an opening for exposing the starting end of the coil conductor layer 3a to the lower surface of the lowermost layer 2a. Part 7
4 (i), and as shown in FIG. 4 (i), the uppermost magnetic layer 2e is provided with an opening 8 for exposing the terminal end f of the coil conductor layer 3d, thereby cutting as shown in FIG. 4 (j). Then, the laminated body 1 manufactured as shown in FIG. 3B has a structure in which the starting end s of the coil conductor 3 is exposed on the lower surface and the terminal end f is exposed at the corresponding position on the upper surface. Such a laminated body 1 is shown in FIG.
By overlapping as shown in (A), the starting end s of the coil conductor 3 of the laminated body 1 adjacent to the upper side overlaps with the terminal end f of the coil conductor 3 on the upper surface of the lower laminated body 1, and the press,
It is integrated by firing. In addition, 5 and 6 are terminals formed to overlap with the coil start end s and the coil end f exposed on the lower surface of the lowermost layer and the uppermost laminated body 1, respectively.
With such a structure, it is not necessary to provide the connection conductor 4 on the side surface of the magnetic body as described above.

[0013]

According to the present invention, since a laminated antenna is constructed by superposing and fixing a plurality of laminated elements, a laminated antenna having a high Q value can be easily obtained without requiring a long manufacturing time. be able to. This makes it possible to provide a high-performance and inexpensive laminated antenna.

[Brief description of drawings]

1A is a perspective view showing an embodiment of a laminated antenna according to the present invention, FIG. 1B is a perspective view showing a laminated element body of this embodiment, and FIG. 1C is an equivalent circuit diagram of FIG. is there.

FIG. 2 is a manufacturing process diagram of the present embodiment.

FIG. 3A is a perspective view showing another embodiment of the laminated antenna according to the present invention, and FIG. 3B is a perspective view showing the laminated body thereof.

FIG. 4 is a manufacturing process diagram of the embodiment in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laminated element 2 Magnetic body 2a-2e Magnetic layer 3 Coil conductor 3a-3d Coil conductor layer 4 Connection conductor 5,6 Terminal 7,8 Opening s Coil conductor start end f Coil conductor end

Claims (2)

[Claims] 1. A laminated body in which a magnetic body and a coil conductor are laminated to form a spirally formed coil conductor, and a plurality of the laminated bodies are superposed and fixed to each other. Stacked antenna. 2. A laminated body in which a magnetic body and a coil conductor are laminated to form a laminated body in which a coil conductor is spirally formed, and then a plurality of the laminated bodies are superposed and fixed to each other. Antenna manufacturing method.