JPH10107511A - Irreversible circuit element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the height of the entire irreversible circuit element without deteriorating the electric and mechanical characteristic by the thinned profile part of a yoke by forming the part of the yoke being a component of a magnetic circuit on which a magnetic assembly is mounted. SOLUTION: In this isolator, a lower yoke 8 on which a magnetic assembly 5 is mounted is made thinner than other parts, the magnetic assembly 5 is placed lower by the thinned profile A and an upper yoke 2 with a permanent magnet 3 adhered thereto is placed lower accordingly. A recessed part 8b is formed to the part of the lower yoke 8 on which the magnetic assembly 5 is mounted so as to make the thickness by the value A thereby making the entire height of the isolator lower. The part to which the recessed part 8b is formed is in the middle of a flat part of the yoke 8 so as to provide a small effect onto the distribution of magnetic lines of force and mechanical strength of the yoke and then the electric characteristic of the isolator is not much deteriorated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a non-reciprocal circuit device used in a high frequency band such as a microwave band, for example, an isolator and a circulator.

[0002]

2. Description of the Related Art As this type of isolator, there is a conventional isolator having a structure as shown in FIGS. 3 is an exploded perspective view of the isolator, FIG. 4 is a plan view in a state where a permanent magnet and upper and lower yokes are removed, and FIG. 5 is a sectional view taken along line XX of FIG.

In this isolator, as shown in FIGS. 3 to 5, a permanent magnet 3 is adhered to an inner surface of a box-shaped upper yoke 2 and arranged, and a substantially U-shaped lower yoke 8 is mounted. A magnetic circuit is formed, and a resin case 7 is provided on an inner bottom surface 8a of the lower yoke 8, and a magnetic assembly 5, matching capacitors C1 to C3, and a terminating resistor R are provided in the resin case 7. The permanent magnet 3 applies a DC magnetic field to the magnetic assembly 5.

The upper yoke 2 and the lower yoke 8 are manufactured by punching a metal plate of a predetermined thickness made of a magnetic metal, bending, drawing, and the like. In addition to the configuration, it also serves to protect the above-mentioned components arranged in the magnetic circuit formed by the upper and lower yokes 2 and 8.

The magnetic assembly 5 includes a disk-shaped ferrite 54.
Three central conductors 51 to 51 made of a thin metal plate
The ground portion 53 is brought into contact with the ferrite 54 and three center conductors 51 to 53 are formed on the insulating sheet 55 (FIGS. 3 and 4).
(Not shown) are interposed and bent so as to form an angle of 120 degrees with each other, and the port portions P1 to P3, which are the tip portions of the respective center conductors 51 to 53, are projected outward. It is configured.

The resin case 7 is made of a resin material having heat resistance and insulation properties, and has a structure in which a bottom wall 7a is integrally formed on a rectangular frame-shaped side wall, and input / output terminals 71, 7 are provided at predetermined locations.
2 and ground terminals 73, 73, an insertion hole 7b is formed in a substantially central portion of the bottom wall 7a, and three capacitor housing recesses 7c and a resistance housing recess 7d are formed in the peripheral edge of the insertion hole 7b. The input / output terminals 71 and 72 and the ground terminal 73 are molded and embedded in the center of the resin, and the external connection portion at one end is provided to be exposed on the outer surface of the bottom wall 7a and the side wall. The other end of each of 71 and 72 is exposed to the inner surface of the bottom wall 7a, and the other end of each ground terminal 73 is provided to be exposed to the inner bottom of the capacitor housing recess 7c and the resistor housing recess 7d.

The magnetic assembly 5 is inserted and arranged in the insertion hole 7b, and the ground portions of the center conductors 51 to 53 on the lower surface of the magnetic assembly 5 are connected to the bottom surface 8a of the lower yoke 8 by soldering. . Matching chip capacitors C1 to C3 are arranged in the capacitor recess 7c, and a chip terminating resistor R is arranged in the resistor recess 7d.

The port portions P1 and P2 of the input / output side center conductors 51 and 52 are connected to the upper surface electrodes of the capacitors C1 and C2 and the portions exposed on the inner surface of the bottom wall 7a of the input / output terminals 71 and 72. Port part P3 is a capacitor C3
And the electrode on one end of the terminating resistor R. The lower electrodes of the capacitors C1 to C3 and the electrode on the other end side of the terminating resistor R are respectively connected to the portions of the ground terminal 73 exposed to the inner surfaces of the capacitor housing recess 7c and the resistor housing recess 7d.

[0009]

A non-reciprocal circuit device of this type is employed in a transmission / reception circuit of a mobile communication device such as a portable telephone. These devices are rapidly becoming smaller and thinner, and there is a strong demand for non-reciprocal circuit devices to be thinner. In response to this demand for thinning, the present inventor has paid attention to reducing the thickness of the yoke constituting the magnetic circuit.

However, in the above-mentioned conventional isolator, the upper yoke 2 and the lower yoke 8 are formed with a constant thickness over the whole, and a certain thickness is required in consideration of electrical characteristics and mechanical strength. Therefore, there is a limit to simply reducing the thickness of the yoke to reduce the thickness. In other words, in the above-mentioned conventional isolator, if the thickness of the yoke is simply reduced, the leakage of the magnetic force at the bent portion of the yoke having a high magnetic flux density increases, and the electrical characteristics are reduced.
There is a problem that the mechanical strength is reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide a non-reciprocal circuit device which can be made thinner without deteriorating its electrical characteristics and mechanical strength.

[0012]

In order to achieve the above object, the present invention provides a magnetic circuit having permanent magnets arranged in a yoke, in which a plurality of central conductors are crossed by a magnetic material. A magnetic assembly placed in contact with the yoke, a matching capacitor connected between the port portion of each of the center conductors and ground, and the matching capacitor, the magnetic assembly, and the like. A non-reciprocal circuit device including a case for storing and holding components, wherein a thickness of a portion of the yoke on which the magnetic assembly is mounted is formed to be thinner than other portions. .

According to the above construction, the thickness of the portion on which the magnetic assembly of the yoke forming the magnetic circuit, that is, the outer shell of the non-reciprocal circuit element is mounted, is formed thin.
Since the magnetic assembly having the reduced thickness can be arranged low, the overall height of the non-reciprocal circuit device can be reduced. This thinning can be performed without substantially lowering the electrical characteristics and mechanical strength.

That is, the portion on which the magnetic assembly of the yoke is mounted is located at the center of the flat surface of the yoke and has a lower magnetic flux density than other portions, so that the influence on the magnetic force distribution is small. Since the influence on the mechanical strength is small, even if this part is thinned, the electric characteristics and the mechanical strength do not decrease.

Further, since the magnetic assembly is arranged in the thinly formed concave portion of the yoke, the magnetic assembly can be easily positioned, and the magnetic assembly can be securely mounted at a predetermined position on the yoke. can do.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the drawings showing embodiments thereof.

FIGS. 1 and 2 show the structure of an isolator according to one embodiment of the present invention. 1 is an exploded perspective view of the isolator, and FIG. 2 is a sectional view taken along line XX of FIG.

In the isolator of this embodiment, FIG.
As shown in FIG. 2, a portion of the inner bottom surface 8a of the lower yoke 8 facing the magnetic assembly 5 has a circular concave portion 8b having a depth A and a size substantially fitting to the outer diameter of the magnetic assembly 5. The magnetic assembly 5 is mounted in the recess 8b with its lower part fitted. The recess 8b is formed by punching or the like.

That is, in the isolator of this embodiment, the thickness of the portion of the lower yoke 8 on which the magnetic assembly 5 is mounted is formed thinner than other portions, 5 are arranged low and the permanent magnet 3 is accordingly
The upper yoke 2 to which is attached is also arranged low. The configuration other than the above is the same as that described in the conventional example, and the description thereof will be omitted.

As described above, in the structure of the present embodiment, the height of the entire isolator is reduced by forming the concave portion 8b in the portion of the lower yoke 8 where the magnetic assembly 5 is mounted and reducing the size A. It can be formed lower by the dimension A.

The portion in which the concave portion 8b is formed is substantially at the center of the flat portion of the yoke 8 constituting the magnetic circuit, and has little effect on magnetic force distribution and mechanical strength of the yoke. Properties and mechanical strength are not significantly reduced. That is, the depth A of the concave portion 8b is set to a size that does not substantially reduce the electrical characteristics and the mechanical strength. For example, in an isolator having a width of 7 mm, a length of 7 mm, and a height of 2.5 mm,
When the yoke is formed using a magnetic metal plate having a thickness of 0.2 mm, the depth A of the recess 8b is set to about 50 to 100 μm.

Further, since the magnetic assembly can be arranged so as to fit into the recess 8b, the positioning of the magnetic assembly can be performed more easily.

In the above embodiment, an isolator has been described as an example. However, the present invention is applicable to a circulator in which the port P3 is configured as a third input / output unit without connecting the terminating resistor R to the port P3. Can be.

The overall structure is not limited to the one shown in FIGS. 1 and 2 of the above embodiment. The present invention provides a non-reciprocal motor in which a magnetic assembly is mounted in contact with a yoke constituting a magnetic circuit. In the circuit element, the thickness of the portion where the magnetic assembly of the yoke is mounted is formed to be thinner than other portions, and other configurations are not particularly limited.

[0025]

As described above, according to the non-reciprocal circuit device according to the present invention, the thickness of the portion where the magnetic assembly of the yoke constituting the magnetic circuit is mounted is made thin, so that the electric circuit can be obtained. Without deteriorating the properties and mechanical properties
The height of the entire non-reciprocal circuit device can be reduced by the reduced thickness. That is, the thickness of the non-reciprocal circuit device can be reduced.

Further, since the magnetic assembly can be arranged in the thinly formed concave portion of the yoke, the magnetic assembly can be easily positioned, and the magnetic assembly can be securely placed at a predetermined position on the yoke. Can be mounted.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an isolator according to one embodiment of the present invention.

FIG. 2 is a sectional view of an isolator according to one embodiment of the present invention.

FIG. 3 is an exploded perspective view of a conventional isolator.

FIG. 4 is a plan view of an embodiment of the present invention and a conventional isolator.

FIG. 5 is a sectional view of a conventional isolator.

[Explanation of symbols]

 2 Upper Yoke 3 Permanent Magnet 5 Magnetic Assembly 51-53 Center Conductor 54 Ferrite 7 Resin Case 71, 72 Input / Output Terminal 73 Ground Terminal 8 Lower Yoke 8b Recess C1-C3 Matching Capacitance (R) Termination Resistance

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hiroshi Tokudera 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Stock Company Murata Manufacturing Co., Ltd. (72) Inventor Yutaka Ishiura 2-26-10 Tenjin, Nagaokakyo-city, Kyoto Stock Murata Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A magnetic circuit in which permanent magnets are arranged in a yoke, a plurality of central conductors are arranged on a magnetic body so as to intersect with each other, and a magnetic material is placed in contact with the yoke. A non-reciprocal circuit device comprising: an assembly; a matching capacitor connected between a port portion of each of the center conductors and ground; and a case for housing and holding components such as the matching capacitor and the magnetic assembly. A nonreciprocal circuit device, wherein a thickness of a portion of the yoke on which the magnetic assembly is mounted is formed thinner than other portions.