JPH0715201Y2 - Polarization plane switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a polarization plane switching device, and more specifically, to a microwave ferrite rod functioning as a Faraday rotator, which is inserted in a waveguide. Input and output dielectrics are arranged on both end faces of the rod, and a resistive film is interposed on a vertical division surface including the axis of the output dielectric, and is formed on a coil bobbin on the outer peripheral surface of the waveguide. The present invention relates to a polarization plane switching device in which magnetic field applying means is provided, and yokes made of magnetic metal are provided at both end surfaces of the magnetic field applying means so as to cover the end surface and a part of both the inner and outer peripheral surfaces thereof.

[Conventional technology]

For example, the conventional polarization plane switching device used for satellite broadcasting reception is designed to pass only the reception wave of the desired channel among the reception waves whose polarization planes are deviated by 90 ° for each channel collected by the parabolic antenna. Used for. Conventionally, as the polarization plane switching device of this type, a device utilizing the Faraday effect of ferrite has been used. 8th
FIG. 9 and FIG. 9 show an example of such a polarization plane switching device. A microwave ferrite rod 4 functioning as a Faraday rotator is provided in a waveguide 2 made of a non-magnetic metal having good conductivity. Inserted, and dielectrics 6 and 8 functioning as an input / output impedance matching device are disposed at both ends thereof. The output side dielectric 8 is divided into two parts on a plane including the axis, and the resistance film 10 is interposed on the divided surface. Waveguide 2
A coil device 14 formed on a coil bobbin is provided as a magnetic field applying means on the outer peripheral surface of the. Coil device
Yokes 16 and 18 made of magnetic metal are attached to both end face portions of 14 so as to cover the coil end face and a part of both circumferential faces. In this polarization switching device, for example, the waveguide 2 is made of aluminum and the microwave ferrite rod 4 is used.
Is made of lithium ferrite, and dielectrics 6 and 8 have a dielectric constant of 6
The resistance film 10 is formed by baking ruthenium oxide on the divided surface of the dielectric 8, and the yokes 16 and 18 are made of thin pure iron with a thickness of about 1 mm.

The polarization plane switching device configured as described above is a coil device 14
It is possible to switch between horizontal polarization and vertical polarization by adjusting the strength of the magnetic field by changing the magnitude of the electric current flowing through. That is, the linearly polarized wave incident on the dielectric 6 is impedance-converted here, and then the plane of polarization is appropriately rotated according to the strength of the magnetic field generated by the coil device 14 while passing through the microwave ferrite rod 4. The adjusted resistance film 10 formed on the dielectric 8 allows an electromagnetic wave perpendicular to the surface of the resistance film 10 to pass therethrough and absorbs an electromagnetic wave orthogonal thereto. Therefore, by setting the former vertical electromagnetic wave as the desired electromagnetic wave and the latter orthogonal electromagnetic wave as the unnecessary electromagnetic wave, it is possible to pass only the received wave of the desired channel.

[Problems to be solved by the device]

In the above-mentioned conventional polarization plane switching device, the waveguide 2 having the microwave ferrite rod 4 and the dielectrics 6 and 8 inserted therein is fitted into the yokes 16 and 18 to fix the components to each other. In addition, the structure prevents the deterioration of the characteristics. Therefore, both abutting surfaces involved in the fitting are subjected to precision processing so that they are in close contact with each other.

However, the yokes 16 and 18 are composed of a disk portion facing the end surface of the coil device 14, an inner cylindrical portion continuously provided on the inner circumference thereof, and an outer cylindrical portion continuously provided on the outer circumference thereof. In order to finish a yoke with such a shape with a predetermined accuracy,
Since a simple plate material or the like takes different processing man-hours and has a small thickness, it is considerably difficult to perform precision processing on it.

Therefore, an object of the present invention is to provide a polarization plane switching device provided with a yoke having a structure that can be easily processed.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention inserts a microwave ferrite rod functioning as a Faraday rotator into a waveguide, and disposes input / output dielectrics on both end faces of this ferrite rod, A resistance film is interposed on a vertical division surface including the axis of the dielectric material for use, magnetic field applying means is provided on the outer peripheral surface of the waveguide, and both end surfaces of this magnetic field applying means are provided.
In a polarization plane switching device in which a yoke made of magnetic metal is arranged so as to cover the end surface and a part of both the inner and outer peripheral surfaces following the end surface, a disk portion in which the yoke contacts the end surface of the coil bobbin,
It is configured by being divided into an inner cylindrical portion that is continuously provided on the inner periphery of the disc portion and an outer cylindrical portion that is continuously provided on the outer periphery of the disc portion. It is characterized in that it is fixed by inserting the protrusion formed on the other side into the hole formed on the other side.

[Action]

With the yoke configured as described above, by dividing the yoke into a simple-shaped disc portion, an inner cylinder portion, and an outer cylinder portion, the disc portion can be easily processed by pressing a plate-shaped material. It is possible to obtain the inner cylinder and the outer cylinder with a predetermined accuracy by simply cutting a pipe material of a predetermined size into a predetermined length, so that it has a processing accuracy equivalent to that of conventional precision processing. The yoke can be easily obtained.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to the drawings.

As shown in FIG. 2, the yokes 16 and 18 in the polarization plane switching device of the present invention include a disc portion b that abuts on the end face of the coil bobbin 12 and an outer cylinder that is continuously provided on the inner circumference of the disc portion b. Part c,
It is divided into three parts, namely, an outer cylinder part a which is continuously provided on the outer circumference of the disc part b. The inner diameter of the inner cylindrical portion c is made slightly smaller than the outer diameter of the waveguide 2 (see FIG. 1) in consideration of the press-fitting process during assembly.

As shown in FIG. 3, a stepped portion d for receiving the inner cylindrical portion c of the yokes 16 and 18 is formed on the inner diameter portion of the coil bobbin 12 up to a predetermined distance from the end surface thereof. An assembling projection e is provided on the portion. Corresponding to the protrusion e, a hole f for inserting the protrusion e is formed in the disc portion b. Note that the protrusion e and the hole f may be provided on the counterpart member depending on the case. These protrusions e and holes f are
The diameter of the protrusion e is made slightly smaller than the inner diameter of the hole f, and the structure is fixed by the elasticity of the protrusion e. The other components are
It is no different from the corresponding parts of the apparatus shown in FIGS. 8 and 9 described as the conventional apparatus.

In assembling, first, the dielectrics 6 and 8 and the ferrite rod 4 are inserted into the waveguide 2. Next, the waveguide 2 with the dielectrics 6 and 8 and the ferrite rod 4 inserted therein is inserted into the center hole of the coil bobbin 12 (FIG. 4). Next, the inner cylinder portion c of the yokes 16 and 18 is press-fitted into the stepped portion d formed on the coil bobbin 12 (Fig. 5). The press-fitting fixes the waveguide 2 in the coil device 14, and the dielectrics 6 and 8 and the ferrite rod 4 in the waveguide 2 are also fixed. Next, the disk portion b is fitted into the coil bobbin 12 using the hole f and the protrusion e (second
Next, the outer cylinder portion a is fitted into the disc portion b by fitting (FIG. 3). Note that this fixed joining may be performed by soldering or welding. In this way, the polarization plane switching device shown in FIG. 1 is constructed.

The yokes 16 and 1 in the polarization plane switching device of the present invention described above.
The outer cylinder portion a, the disc portion b, and the inner cylindrical portion c are divided into three parts, which are constructed by assembling them. The outer cylinder part a and the inner cylinder part c are obtained by simply cutting the ready-made pipe material, and the disc part b is made of a plate material.
It can be obtained by pressing this. This is called cutting and pressing, which is an easy task by itself, and the required accuracy as a polarization plane switching device can be easily and sufficiently maintained without depending on the product accuracy of the raw material, without performing complicated processing. can do. Therefore, according to the present invention, the number of processing steps can be significantly reduced without lowering the product performance.

In order to fix the disc portion b of the yokes 16 and 18 to the coil bobbin 12, as shown in FIG. 6, the protrusion e is made longer than the thickness of the disc portion b, and its tip is As shown in FIG. 7, the structure may be such that thermocompression bonding (thermocompression bonding part g) is performed.

[Effect of device]

As described above, according to the present invention, by dividing the yoke into appropriate structural parts and assembling them,
Without deteriorating the characteristics of the polarization plane switching device, manufacturing can be facilitated and the number of processing steps can be significantly reduced.

[Brief description of drawings]

1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is an exploded perspective view of the yoke in FIG. 1, FIG. 3 is a partial sectional view showing a state in which the yoke is mounted on a coil bobbin, and FIG. Is a vertical cross-sectional view showing a semi-manufactured state of the polarization plane switching device according to the present invention, and FIG. 5 is a vertical cross-sectional view showing a press-fit state of the yoke inner cylinder portion.
6 and 7 are partial sectional views showing different states when the yoke disk portion is fixed to the coil bobbin by crimping, FIG. 8 is a vertical sectional view of a general polarization plane switching device, and FIG. 9 is a sectional view. FIG. 9 is an end view of the polarization plane switching device of FIG. 8 viewed from the output side. 2 ... Waveguide, 4 ... Ferrite rod, 6,8 ... Dielectric, 1
0 ... Resistive film, 12 ... Coil bobbin, 14 ... Coil device, 16,18 ... Yoke, a ... Outer cylinder part, b ... Disc part,
c ... Inner cylinder part, d ... Stepped part, e ... Protrusion, f ...
hole.

Claims (1)

[Scope of utility model registration request] 1. A microwave ferrite rod functioning as a Faraday rotator is inserted in a waveguide, and input / output dielectrics are disposed on both end faces of the ferrite rod, and the axis of the output dielectric is the center. A resistive film is interposed on the vertical division surface including the magnetic field applying means configured on the coil bobbin on the outer peripheral surface of the waveguide, and both end surfaces and both the inner and outer surfaces following the end surface of the magnetic field applying means are provided. In a polarization plane switching device in which a yoke made of magnetic metal is arranged so as to cover a part of the peripheral surface, a disk portion in which the yoke is in contact with an end surface of the coil bobbin, and an inner periphery of the disk portion are continuously provided. The inner cylinder portion and the outer cylinder portion that is continuously provided on the outer periphery of the disc portion, and the disc portion of the yoke and the coil bobbin are formed on one side with the protrusion formed on the other side. By inserting it into the hole Polarization plane switching device characterized by being fixed in place.