JP2606940Y2 - Variable capacitor - Google Patents

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 in a tuning circuit of a consumer receiver or the like.

[0002]

2. Description of the Related Art Heretofore, as a variable capacitor of this type, a relatively small-sized polyvaricon (registered trademark) or the like has been known, and is configured as follows, for example.

That is, the variable capacitor is provided between the substrate and the pressing plate, a group of rotors pivotally supported around a rotation axis, a group of fixedly arranged stators, and disposed on the pressing plate. And at least one trimmer capacitor, and a trimmer cover that is put on the pressing plate so as to cover the trimmer capacitor.

[0004] The variable capacitor thus configured is
A variable capacitance section having a plurality of capacitance sections formed by a rotor group and a stator group between the substrate and the push plate is provided to a tuning circuit of ANT / OSC such as AM-FM, and provided on the push plate, for example. A trimmer capacitor having a maximum capacitance of about 5 pF can be used for fine adjustment.

Here, in each of the trimmer capacitors, a rotor portion is disposed between a pressing plate and a cover on a ground plate connected to a rotor group or the like of the variable capacitance portion. Further, the stator terminal serving as a hot terminal is usually connected to a stator group of the variable capacitance section.

According to the variable capacitor thus configured, when adjusting the capacitance of each trimmer capacitor, the nut portion formed at the end of the rotor rotation shaft of the trimmer capacitor is operated by a driver or the like. By rotating the rotor with respect to the stator, the capacitance of the trimmer capacitor can be adjusted to a desired capacitance value.

[0007]

However, in the variable capacitor configured as described above, a load is applied in the thrust direction to the rotating shaft of the trimmer capacitor when adjusting the capacity of the trimmer capacitor. Therefore, the load changes the electrode conditions of the rotor group and the stator group of the rotor group and the stator group, that is, the interval in the thrust direction, and the load resistance is weak. As a result, the capacitance of the trimmer capacitor fluctuates. Thus, there has been a problem that accurate adjustment of the capacity of the trimmer capacitor cannot be performed.

In view of the above, it is an object of the present invention to provide a variable capacitor capable of accurately adjusting its capacity by improving the load-bearing characteristics of a trimmer capacitor.

[0009]

According to the present invention, there is provided a rotor group rotatably supported around a rotation axis between a substrate and a pressing plate, and a stator group fixedly arranged. And at least one trimmer capacitor disposed on the push plate, and a variable capacitor including a trimmer cover placed on the push plate so as to cover the trimmer capacitor. This is achieved by a variable capacitor, characterized in that, in the area of the fixed part, a projection that can abut the stator plate of the trimmer capacitor is formed.

[0010]

According to the above construction, since the protrusion projecting from the inner surface of the trimmer cover is in contact with the stator plate of the trimmer capacitor, the load in the thrust direction is applied to the trimmer capacitor when adjusting the trimmer capacitor. When the load is applied, even if the rotor plate of the trimmer capacitor is deformed together with the trimmer cover due to this load, the projection of the trimmer cover presses the stator plate of the trimmer capacitor. Therefore, the stator plate is deformed following the deformation of the rotor plate, and the gap between the stator plate and the rotor plate can be kept substantially constant. Thus, the load-bearing characteristics of the trimmer capacitor can be substantially improved, and the capacitance of the trimmer capacitor does not fluctuate due to the load at the time of adjustment, and the capacitance of the trimmer capacitor is accurately adjusted. You will get.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 shows the overall configuration of an embodiment of the variable capacitor according to the present invention, and FIG. 2 shows the trimmer capacitor section in an exploded manner in detail.

In FIG. 1, a variable capacitor 10 is connected to a variable capacitance section 11 provided for a tuning circuit such as an ANT / OSC such as an AM / FM circuit of a receiver, and is connected in parallel to the variable capacitance section 11 for fine adjustment. And a trimmer capacitor unit 20 provided for

The variable capacitance section 11 is composed of a stator group 13 composed of a laminated metal plate and a polyester film of an insulating member on a substrate 12, and a vertical rotating shaft (not shown) fitted to the stator group 13 respectively. And a group of rotors 14 rotatably supported therearound. Here, a part of each rotor group 14 is, for example, an ANT / OS for AM.
A maximum capacity of 140/80 pF is provided for the C circuit, and another part is provided for a maximum capacity of 20 pF for the ANT / OSC circuit for FM.

As shown in FIG. 2, the trimmer capacitor section 20 has at least one, in the case shown, four trimmer capacitors 23, 24, 25, between the pressing plate 21 and the trimmer cover 22. 26 is configured as follows.

An earth plate 27 is placed on the upper surface of the push plate 21 so as to penetrate the edges facing each other, and an opening is formed on the upper surface of the push plate 21 on both sides of the earth plate 27. The trimmer capacitors 23, 24,
Rotating shafts 23a, 24 of the rotor portions constituting
a, 25a, 26a are fitted and fixed.

The grounding plate 27 is provided with lead wire connecting tongues 27a and 27b formed to protrude outward from both ends as shown in the figure.

Next, an insulating film 28 made of, for example, polyester is formed from above with a protrusion 21a having a peripheral end formed so as to protrude upward at opposing edges of the upper surface of the push plate 21. It is placed so as to be inscribed in. Subsequently, the through holes of the stator plates 23b, 24b, 25b, 26b constituting the respective trimmer capacitors 23, 24, 25, 26 are fitted into the projections 21a from above, whereby the stator plate is formed. 23b, 24b, 2
5b and 26b are mounted on the insulating film 28.

In this case, the top of the rotating shaft of the variable capacity section 11 is supported by the through hole 27c of the ground plate 27, and the rotating shafts 23a and 24 are further fitted into the through hole 27d of the ground plate 27.
The rotor plates 23c, 24c, 25c, and 26c of the trimmer capacitors 23, 24, 25, and 26 are connected to the ground plate 27 by the shoulders a, 25a, and 26a being seated and locked.
It can rotate without abutting on it.

Finally, on the upper surface of the pressing plate 21, a trimmer cover 22 is provided with the above trimmer capacitors 23, 24, 25, and 2.
6, and each corner is screwed by a nut 29. Thus, the rotating shafts 23a, 24
a, 25a and 26a are sandwiched in the thrust direction and can be sandwiched between the push plate 21 and the trimmer cover 22.

The above configuration is the same as that of the conventional variable capacitor. However, in the variable capacitor 10 according to the embodiment of the present invention, the inner surface of the trimmer cover 22 (the surface in the direction of the variable capacitance portion) is shown in FIG. As described above, at the position adjacent to each projection 21a, that is, at the end opposite to each corner of the trimmer stator plates 23b, 24b, 25b, 26b screwed by the nut 29, the projection 30 protruding downward is provided.
Are formed. As shown in FIG. 4, each protrusion 30 has a length equal to each of the trimmer capacitors 23, 24, 2.
5, 26 stator plates 23b, 24b, 25b, 26b
It has been selected so that it just touches the surface. Thereby, the stator plates 23b, 24b, 25b, 26b
Correspond to the corresponding rotor plates 23c, 24c, 25c, 26c
Is configured to be able to maintain a constant distance from Here, the illustration of the insulating film 28 is omitted in FIG.

In FIG. 4, the trimmer capacitor 2
3, the other trimmer capacitors 24, 2
5 and 26 have the same configuration.

The embodiment of the present invention is configured as described above. When adjusting the capacitance of each of the trimmer capacitors 23, 24, 25, 26, the trimmer capacitors 23, 24,
The nuts formed at the ends of the rotation shafts 23a, 24a, 25a, 26a of the rotation plates 25, 26 are operated by a driver or the like, whereby the rotor plates 23c, 24c, 25c, 2 are rotated.
6c is rotated with respect to the stator plates 23b, 24b, 25b, 26b. Thereby, the rotor plates 23c, 24
c, 25c, 26c and stator plates 23b, 24b, 25
The overlapping area between the trimmer capacitors 23, 24, 25, and 26 changes, and thus the capacitance of the trimmer capacitors 23, 24, 25, and 26 can be adjusted to a desired capacitance value.

Here, the trimmer capacitors 23, 24, 2
For example, when adjusting the capacitance of the trimmer capacitor 2
As shown by an arrow A in FIG. 4, a load is applied to the third rotating shaft 23a in the thrust direction by a driver (not shown). This load may cause the rotor plate 23c, the push plate 21, and the trimmer cover 22 to bend downward along with the rotating shaft 23a. In this case, the deformation of the trimmer cover 22 causes the protrusion 30 provided on the inner surface of the trimmer cover 22 to push the stator plate 23b downward. Therefore, the stator plate 23b is moved downward by the same distance as the downward movement of the rotating shaft 23a and the rotor plate 23c. This allows
When operating the trimmer condenser 23, the rotating shaft 23a
Even if the trimmer capacitor 2 is deformed downward together with the rotor plate 23c, the push plate 21, and the trimmer cover 22,
3 can always be kept constant between the rotor plate 23c and the stator plate 23b.
There is no fluctuation due to the load of 3a.

Thus, the trimmer capacitors 23, 24,
The load-bearing characteristics of the trimmer capacitors 25, 26 can be improved, and the capacitance of the trimmer capacitors 23, 24, 25, 26 can be accurately adjusted.

[0025]

As described above, according to the present invention, there is provided an extremely excellent variable capacitor in which the capacity adjustment can be performed accurately by improving the load-bearing characteristics of the trimmer capacitor. You will get.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view of a trimmer capacitor part of the trimmer capacitor of FIG.

FIG. 3 is a partially cutaway plan view of the trimmer capacitor unit of FIG. 2;

FIG. 4 is a partially enlarged cross-sectional view of the trimmer capacitor section of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Variable capacitor 11 Variable capacity part 12 Substrate 13 Stator group 14 Rotor group 20 Trimmer capacitor part 21 Push plate 22 Trimmer cover 23, 24, 25, 26 Trimmer capacitor 23b, 24b, 25b, 26b Stator plate 27 Ground plate 28 Insulating film 29 Nut 30 protrusion

Claims (1)

(57) [Scope of request for utility model registration] 1. A group of rotors rotatably supported around a rotation axis between a substrate and a pressing plate, a group of stators fixedly disposed, and at least one of the plurality of stators disposed on the pressing plate. In a variable capacitor including a trimmer capacitor and a trimmer cover that is placed on the push plate so as to cover the trimmer capacitor, the variable capacitor including the trimmer cover is provided on the inner surface of the trimmer cover in a region of a fixing portion to the push plate to a stator plate of the trimmer capacitor. A variable capacitor characterized by having a protruding portion that can be in contact therewith.