JP2000124069A - Variable capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitor which is difficult to change with time elapsed by preparing upper electrodes on the upper surface of a stator, a rotatable driver plate on the upper surface side, and a contact that is connected electrically to the driver plate on its one end side and contacts which make contact with the upper surface of the stator on its other end. SOLUTION: A stator 4 is laminate composed of a plurality of dielectric sheets, and has a through-hole 4a in its center. A stator electrode 4b is formed on its internal layer member, and an end of it is extracted to the outside to connect to an external electrode 4c. An indent 4d is formed on the lower side of the stator 4 to accommodate lower end of an eyelet terminal 5, while upper electrode 4e are formed on the upper side. A driver plate 6 is set rotatably on the stators 4. An eyelet part 5a is pierced from the lower side of the stator 4 and is caulked at the upper side of the driver plate 6, while a contact 6c makes contact with the upper plane of the stator 4 in caulking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable capacitor used for various electronic devices.

[0002]

2. Description of the Related Art As shown in FIG. 3, a conventional variable capacitor is provided on a stator 1 having a stator electrode 1a in an inner layer.
A rotor 2 having a rotor electrode 2a is disposed on the lower surface side, and a grommet terminal 3 is passed through the center of the stator 1 and the rotor 2, and an upper end portion is caulked to the upper surface of the rotor 2 and provided at a lower end of the grommet terminal 3. Due to the resiliency of the spring portion 3a, the rotor 2 is rotatably pressed against the stator 1.

[0003]

The variable capacitor is required to maintain the capacity once adjusted, but the rotor electrode 2a is pressed against the stator 1 by the spring property of the spring portion 3a. Therefore, there is a problem that the space between the rotor electrode 2a and the stator electrode 1a changes due to a change over time such as metal fatigue of the spring portion 3a, and as a result, the capacitance value of the variable capacitor fluctuates.

Accordingly, the present invention provides a variable capacitor that is unlikely to change with time.

[0005]

In order to achieve this object, a variable capacitor according to the present invention is provided with a stator made of a dielectric, a stator electrode provided in an inner layer of the stator, and provided on an upper surface of the stator. An upper surface electrode facing the stator electrode, a driver plate rotatably provided on the upper surface side of the stator, and a contact having one end connected to the driver plate and the other end contacting the upper surface of the stator. That is the configuration provided with.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention provides a stator comprising a dielectric, a stator electrode provided on an inner layer of the stator, and a stator electrode provided on an upper surface of the stator. An opposing upper surface electrode, a driver plate rotatably provided on the upper surface side of the stator, and a contact having one end connected to the driver plate and the other end contacting the upper surface of the stator. The variable capacitor is characterized in that the upper surface electrode that forms a capacitance facing the stator electrode is provided on the upper surface of the stator, so that the capacitance can be fixed.

According to a second aspect of the present invention, there is provided the variable capacitor according to the first aspect, wherein a plurality of upper electrodes are provided, and the capacitance can be selected.

According to a third aspect of the present invention, there is provided the variable capacitor according to the second aspect of the present invention, wherein each of the upper electrodes has a different area, and a plurality of capacitors can be formed.

According to a fourth aspect of the present invention, there is provided the variable capacitor according to the second or third aspect, wherein a plurality of contacts are provided, and a capacitance is formed by combining a plurality of upper electrodes. Can be done.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view showing a variable capacitor according to the present invention.

Reference numeral 4 denotes a stator. This stator 4
This is a laminate composed of a plurality of dielectric sheets, and a through hole 4a is provided in the center thereof. A stator electrode 4b is provided on the inner layer, and one end thereof is drawn out to the outside and connected to the external electrode 4c as shown in FIG.
Returning to FIG. 1, the lower surface of the stator 4 is provided with a concave portion 4d for accommodating a lower end portion of the eyelet terminal 5 described later, and the upper surface is provided with an upper surface electrode 4e.

Reference numeral 6 denotes a driver plate. The driver plate 6 is formed by forming stainless steel for a spring into a disk shape. The driver plate 6 has a central portion recessed downward, and a through hole 6a is provided in the center. A driver groove 6 for engaging an adjustment driver (not shown) with the upper surface portion.
b, and a contact 6c extending outward is integrally provided on the lower surface side.

Reference numeral 5 denotes an eyelet terminal. This eyelet terminal 5
Is a cylindrical member formed by squeezing a metal material. A cylindrical eyelet portion 5a and a terminal portion 5b pulled out from the lower end thereof
And

Then, these parts are as shown in FIG.
The driver plate 6 is arranged on the stator 4, and the eyelets 5 a penetrate from below the stator 4 and are caulked on the upper surface side of the driver plate 6. Further, at the time of this caulking, the contact 6c is pushed upward by the contact with the stator 4, so that the contact 6c surely comes into contact with the upper surface of the stator 4 due to the spring property generated thereby. I have.

The variable capacitor thus configured is
By rotating the driver plate 6, the contact 6c comes into contact with the upper surface electrode 4e, and a capacitance is formed between the upper surface electrode 4e and the stator electrode 4b. Then, the electric charge on the upper electrode 4e is led out through the contact 6c, the driver plate 6, and the eyelet terminal 5 which are in contact with the upper electrode 4e.

That is, this variable capacitor is different from the conventional capacitor shown in FIG. 3 in which the rotor electrode 2a is formed on the rotor 2 itself, and the stator electrode 4b and the upper surface electrode 4e forming the capacitance are integrated with the stator 4. Therefore, the interval between these electrodes does not change, and a change with time can be prevented.

On the upper surface of the stator 4, a plurality of upper electrodes 4e are provided as shown in FIG. That is, by rotating the driver plate 6, the contact 6
The upper electrode 4e with which c contacts can be selected from among the plurality of upper electrodes 4e, and various capacitances can be selected by making the areas of the upper electrodes 4e different. For example, by subdividing the upper surface electrode 4e and arranging the upper electrode 4e having a gradually increasing area in ascending order, the capacitance can be adjusted stepwise from a smaller capacitor to a larger capacitor as in the conventional case. .

Further, by providing a plurality of contacts 6c connected to the driver plate 6, a plurality of upper surface electrodes 4 are provided.
Since e can be used in combination, the maximum capacitance value of the variable capacitor can be increased. In this regard, it leads to miniaturization of the product.

Further, since the upper surface electrode 4e facing the stator electrode 4b is provided integrally with the stator 4, the stator electrode 4b is connected to the stator electrode 4b as shown in FIG.
And the area of the stator 4 can be effectively used. This is shown in FIG.
In the case of the conventional variable capacitor shown in FIG.
Since the shape of is provided on the rotating body, it becomes a semicircular shape,
The maximum capacitance value is limited by the shape of the rotor 2 such that the effective shape of the opposed stator electrode 1a is substantially the same as the semicircular shape of the rotor electrode 2a, as shown in FIG. By forming the upper surface electrode 4e facing the stator electrode 4b on the stator 4,
This is because there is no longer any restriction on the electrode shape due to the shape of the driver plate 6, and the surface of the stator 4 can be effectively used without waste.

Further, in the case of the conventional variable capacitor shown in FIG. 3, precision processing such as mirror polishing is required on the lower surface side of the rotor 2 in order to form the rotor electrode 2a. In the variable capacitor according to the present embodiment, the upper electrode 4e facing the stator electrode 4b is provided on the stator 4, so that the processing accuracy of the driver plate 6 itself is not so required, and the processing cost can be reduced. You can do it.

Further, in the case of the conventional variable capacitor shown in FIG. 3, since the rotor electrode 2a is pressed against the stator 1, the silicon is interposed between the rotor 1 and the stator 1 to make the rotation of the rotor 2 smooth. It is necessary to interpose a lubricating oil 7 such as oil, and when the cleaning is performed after the adjustment, the lubricating oil 7 flows out and the capacity value changes. However, in the variable capacitor of the present embodiment shown in FIG. if there is,
Since the lubricating oil 7 is not provided between the stator electrode 4b and the upper surface electrode 4e, the capacity does not change due to cleaning.

Further, in the case of the conventional variable capacitor shown in FIG. 3, since the rotor electrode 2a is provided on the lower surface of the rotor 2, the lower end portion of the eyelet terminal 3 for pressing the rotor electrode 2a against the stator 1 is provided. Spring part 3a
However, in the case of the variable capacitor shown in FIG.
Thus, the height of the variable capacitor can be reduced without requiring a.

The top electrode 4e can be easily adjusted by shortening the adjustment time by arranging several kinds of the upper surface electrodes 4e in advance that can obtain a frequently used capacitance value.

[0024]

As described above, according to the present invention, since the upper surface electrode is formed on the upper surface of the stator having the stator electrode, it is possible to prevent the variable capacitor from changing over time.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a variable capacitor according to an embodiment of the present invention.

FIG. 2 is a sectional view of the variable capacitor.

FIG. 3 is a sectional view of a conventional variable capacitor.

[Explanation of symbols]

 Reference Signs List 4 Stator 4b Stator electrode 4e Upper electrode 6 Driver plate 6c Contact

Claims (4)

[Claims] 1. A stator made of a dielectric, a stator electrode provided on an inner layer of the stator, an upper surface electrode provided on an upper surface of the stator and facing the stator electrode, and rotatable on the upper surface side of the stator. And a contact having one end connected to the driver plate and the other end in contact with the upper surface of the stator. 2. The variable capacitor according to claim 1, wherein a plurality of upper electrodes are provided. 3. The variable capacitor according to claim 2, wherein the area of each upper electrode is different. 4. The variable capacitor according to claim 2, wherein a plurality of contacts are provided.