JPH088646A - Oscillator frequency adjuster - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to adjust minute frequencies without using screws, eliminating problems such as damage to the dielectric due to over-turning of screws, detachment from the screw groove of the screw, and crushing of the screw groove To provide a frequency adjuster for a dielectric resonator. A microwave oscillation circuit comprising a microstrip line circuit, a dielectric disposed in proximity to the microstrip line, the microstrip line circuit, and a shield case accommodating the dielectric, The shield case is provided with a rotor that faces the upper surface of the dielectric and moves up and down by rotation, and the rotation shaft of the rotor is attached so as to be rotatable at a predetermined distance from the center of the dielectric.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency adjuster for a microwave oscillator circuit.

[0002]

2. Description of the Related Art Conventionally, a local oscillator used in a microwave oscillator circuit is as shown in FIG. 3, in which 1 is a shield case, 2 is a substrate, 3 is a lower conductor, and 4 is a microstrip line. Reference numeral 5 is a dielectric, and 6 is a support having a low dielectric constant. The shield case 1 is provided with a metal adjusting screw 20, which is screwed through the upper portion of the shield case 1 to rotate the adjusting screw 20. Adjusting screw 2 by
The bottom surface 21 of 0 can be arbitrarily brought close to the top surface 9 of the dielectric 5. Therefore, by adjusting the adjusting screw 20 to bring it closer to the dielectric 5,
And the coupling capacitance between the microstrip line 4 changes,
As a result, the resonance frequency of the dielectric resonator can be changed, and the oscillation frequency of the microwave oscillation circuit can be adjusted. However, if the adjusting screw 20 of the conventional dielectric resonator is rotated too much, the adjusting screw 20 comes into contact with the dielectric 5 and damages the dielectric 5, or the screw 20 is caught in the thread groove and falls into the case. There was a problem such as crushing the screw groove.

[0003]

As described above, conventionally, since the screw is used for adjusting the frequency of the dielectric resonator, the dielectric 5 is damaged due to excessive turning of the screw, and the screw from the screw groove of the screw is removed. However, the problem of the present invention is to solve the above problems and to provide a frequency adjuster for a dielectric resonator capable of adjusting a minute frequency without using a screw. To do.

[0004]

In order to solve the above-mentioned problems, the present invention provides a microstrip line circuit and a dielectric material arranged in the vicinity of the microstrip line.
In a microwave oscillation circuit composed of the microstrip line circuit and a shield case accommodating a dielectric, a rotor facing the upper surface of the dielectric and rotating up and down is provided in the shield case. The rotary shaft is attached so as to be rotatable with a predetermined distance from the center of the dielectric.

[0005]

With the above-described structure, in the frequency adjusting device of the microwave oscillator according to the present invention, the bottom surface of the rotor is formed so as to be inclined with respect to the upper surface of the dielectric material, and the upper surface of the dielectric material faces the upper surface of the dielectric material. Are arranged so as to be rotatable, and the center axis of the rotor and the center axis of the dielectric are
The rotor shaft is separated by a predetermined distance, and the rotor's rotating shaft is fitted into the shield case so that it can rotate freely.The central shaft is placed through the shield case, and the central shaft is crimped while penetrating the shield case. The rotor and the rotary knob are rotatably held by the dielectric and are electrically coupled while the distance between the rotor and the dielectric is changed. By rotating the central shaft, the rotor rotates while contacting the inner wall of the rotation hole that penetrates the shield case, and thereby the distance between the dielectric and the rotor changes. Therefore, the capacitance taken out between the dielectric and the rotor is variable.

[0006]

Embodiments of the frequency adjusting tool for a microwave oscillator using a dielectric material according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a sectional view of a main part of a microwave oscillation circuit using a dielectric resonator according to the present invention, in which 1 is a shield case, 2 is a substrate, 3 is a lower conductor, and 4 is a lower conductor.
Is a microstrip line, 5 is a dielectric, is fixed to the upper surface of the substrate 2 by a support 6, and 7 is an adjusting rotor having a rotating shaft fitted in the shield case 1.
Is a knob for rotating the rotor 7.

The rotor 7 is made of metal as a whole, and the bottom surface 9 of the rotor 7 is formed so as to incline at a predetermined angle with respect to the top surface 9 of the dielectric 5 and faces the top surface 9 of the dielectric 5. While rotating freely, the center axis 12 of the rotor 7 and the center 13 of the dielectric 5 are separated by a required distance 1
It is configured to be separated by only 4. The rotating shaft 17 of the rotor 7 is fitted into the shield case 1 and is caulked while penetrating the shield case 1 so as to be rotatable. A rotary knob 8 is provided above the central shaft 12, and the rotor 7 is rotated by rotating the rotary knob 8.
Is designed to rotate. Since the bottom surface 9 of the rotor 7 is inclined at a predetermined angle with respect to the top surface 9 of the dielectric 5, when the rotor 7 is rotated, the dielectric 5
The distance between the rotor and the rotor 7 changes. Therefore, the electrostatic capacitance taken out between the dielectric 5 and the rotor 7 is variable.

Next, a specific example of the frequency adjusting method using the rotor 7 of the oscillation circuit having the above-mentioned structure will be described. The rotation starts when the point 15 on the bottom surface of the rotor 7 is located on the center 13 of the dielectric 5 (at this time, the distance between the bottom surface 10 of the rotor 7 and the top surface 9 of the dielectric 5 is the closest position). However, due to the inclination of the bottom surface of the rotor 7, the point 11 on the bottom surface of the rotor 7 gradually approaches the top surface 9 of the dielectric 5 as the rotor 5 rotates, which causes the dielectric 5 and the bottom surface 10 of the rotor 7 to be separated from each other. As the distance increases, the oscillation frequency gradually decreases. Due to the above structure, even if the rotor 7 is rotated too much, it only returns to the original position again, and unlike the conventional case, the screw does not get caught in the screw groove and fall into the case.

FIG. 2 is a sectional view of an essential part of an embodiment of the assembly of the frequency adjusting tool according to the present invention. A groove 31 is formed on the upper side surface of the rotary shaft 8 of the rotor 7, and an E ring 32 is formed in the groove 31. The rotor 7 is held in the shield case 1 by being fitted and caulked with the rotary shaft 8. Further, elastic members 33 having protrusions 34 and 35 formed therein are fitted to the lower side of the rotating shaft 8 of the rotor 7 and the surface where the rotor 7 contacts the shield case 1, and the protrusions 34 and 35 form the shield case 1 and the rotor. The rotor 7 can be rotated in parallel with respect to the shield case 1 by pressing down on the shield case 1.

Further, in order to make it easier to rotate the rotor using a screwdriver or the like, a groove for rotation is provided in the upper part of the rotor, and after the frequency adjustment, the shield case 1 and the rotor 7 are fixed, and the frequency is thereby adjusted. May be fixed by using, for example, an adhesive so as not to change.

[0011]

As described above, according to the frequency adjusting tool of the oscillator of the present invention, the dielectric is damaged or the screw is damaged by the contact with the dielectric due to the excessive adjustment screw turning. It is possible to provide a frequency adjuster that does not cause problems such as being caught in the screw groove and falling into the case, or the screw groove being crushed.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of an embodiment of a frequency adjuster according to the present invention.

FIG. 2 is a cross-sectional view of essential parts of an embodiment of assembly of the frequency adjusting tool according to the present invention.

FIG. 3 is a cross-sectional view of a main part of an example of a conventional frequency adjuster.

[Explanation of symbols]

 1 shield case 2 substrate 3 lower conductor 4 microstrip line 5 dielectric 6 support

Claims (5)

[Claims] 1. An oscillation circuit for a microwave comprising a microstrip line circuit, a dielectric arranged in proximity to the microstrip line, the microstrip line circuit, and a shield case accommodating the dielectric. , A rotor that is opposed to the upper surface of the dielectric and moves up and down by rotation is provided in the shield case, and the rotation shaft of the rotor is attached so as to be rotatable at a predetermined distance from the center of the dielectric. A frequency adjusting tool for an oscillation circuit characterized by the above. 2. The frequency adjusting tool for an oscillation circuit according to claim 1, wherein an E-ring is used as a locking member for locking the rotor in the shield case. 3. Between the rotor and the shield case,
The frequency adjuster for an oscillation circuit according to claim 1, further comprising an elastic member fitted to the rotation shaft of the rotor. 4. A frequency adjusting tool for an oscillation circuit according to claim 1, wherein a rotation groove is provided on an upper portion of the rotor. 5. The frequency adjusting tool for an oscillation circuit according to claim 1, wherein an adhesive is used as a fixing material for fixing the rotor and the shield case after the frequency adjustment.