JPH0227557Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an LC composite component for a low-pass filter in which a magnetic material serving as an inductance and a capacitor are provided coaxially with respect to a through conductor.

Figure 1 shows a conventional example of this type of L-C composite component, in which a dielectric ceramic capacitor 1 formed in a cylindrical shape is shown.
A cylindrical magnetic body 2 made of ferrite beads or the like is fitted into the inner diameter of the magnetic body 2, and a straight rod-shaped through conductor 3 is passed through the through hole 2a of the magnetic body 2, and the through terminal 3 is inserted into the through hole 2a of the magnetic body 2. , it has a structure in which it is electrically connected to the electrode of the capacitor 1 by a header portion 4 and a washer-like electrode connecting body 5. The ceramic capacitor 1 has an outer electrode 6 and a gap in the center.
Two inner peripheral electrodes 7, 8 separated from each other by g ₁
and lead electrodes 9, 1 formed by leading out the inner peripheral electrodes 7, 8 from both end faces in the axial direction to the outer peripheral end.
0, the header portion 4 and the electrode connector 5 are connected and fixed by soldering 11 and 12.

As shown in FIG. 2, the conventional L-C composite component described above has electrodes 6-7, 6-8 of the magnetic capacitor ₁ on both ends of the inductance L1 formed by the magnetic material 2.
A π-type low-pass filter is formed by connecting capacitances C ₁ and C ₂ between them.

However, this conventional L-C composite part
Since the ceramic capacitor 1 has a cylindrical shape and requires inner electrodes 7 and 8, solder adheres to the inner electrodes 7 and 8, and cracks occur in the porcelain due to the shrinkage stress of the solder. The situation was ripe. Also,
In some cases, the flux used for soldering remained within the inner diameter of the ceramic capacitor 1, adversely affecting its characteristics. For this reason, the L-C composite part shown in FIG. 1 has had to be limited to a special range of uses.

In order to eliminate the above-mentioned drawbacks, an LC composite component having the structure shown in FIG. 3 has been proposed. This L-C composite part has a pair of electrodes 17 and 18 arranged inside a stepped cylindrical external terminal fitting 15 having a through hole 14 at the bottom 13 and around a through hole 16 opened on both sides in the thickness direction. An annular ceramic capacitor 19 is fixed by soldering so that the electrode 18 is in contact with the bottom part 13, and the electrode 17 has a header part 20a of a through conductor 20 passed through the through hole 16 of the ceramic capacitor 19. A structure in which a cylindrical magnetic material 22 made of ferrite, ferrite beads, etc. is embedded in an insulating resin 21 filled inside the external terminal fitting 15 so as to go around the through conductor 20 in an annular manner. It is becoming. 23 is an insulating resin.

The L-C composite component described above can eliminate the drawbacks of the one shown in FIG. However, due to its structure, it is not possible to form a π-shaped equivalent circuit like the L-C composite component shown in Figure 1, resulting in a T-shaped filter circuit as shown in Figure 4. It had the disadvantage that its characteristics and functions were inferior to those shown in FIG.

The present invention is based on the above-mentioned cylindrical and disc-through type L.
-C Eliminates each defect of composite parts and has high reliability.
Moreover, it is an object of the present invention to provide an LC composite component that has a π-shaped equivalent circuit and can exhibit advanced characteristics and functions as a filter.

In order to achieve the above object, the present invention provides an L-C with a magnetic material and a capacitor provided around the through conductor.
The capacitor is a composite component, and the capacitor is configured by stacking in series two plate-shaped capacitors having electrodes on both sides in the thickness direction with a through hole, and the magnetic body has an axial hole. The capacitor has a cylindrical shape, and is inserted so that most of it is located in the through hole of the two capacitors, and the mutually overlapping electrodes of the two capacitors are electrically connected to the external terminal fitting. and the other two electrodes are electrically connected to the through conductor that axially passes through the shaft hole of the magnetic body, the through conductor includes a header portion and an electrode connection body, and the through conductor includes a header portion and an electrode connecting body, The header portion and the electrode connector are electrically connected to the other two electrodes so as to close the through holes on both sides of the capacitor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The content of the present invention will be specifically described below with reference to the accompanying drawings, which are examples. Figure 5 shows the L according to the present invention.
-C is a front sectional view of the composite part. In the figure,
Reference numerals 24 and 25 designate capacitors made of dielectric ceramics, grain boundary insulation type, reduction reoxidation type semiconductor ceramics, or the like. Each of the capacitors 24 and 25 is formed into a disk shape having through holes 26 and 27 in the center, and electrodes 28 and 29 and 30 and 31 are provided on both sides in the thickness direction where the through holes 26 and 27 are opened.
It is covered with These capacitors 24 and 25 are stacked in series by bonding and fixing electrodes 29 and 30 to each other.

32 is a magnetic material serving as an inductance. The magnetic body 32 is formed into a cylindrical shape having an axial hole 33 using ferrite beads or ferrite, and
The capacitors 24 and 25 are fitted into through holes 26 and 27 of the capacitor assembly.

34 is a through conductor. The through conductor 34 has a straight rod portion passing through the shaft hole 33 of the magnetic body 32 and a header portion 3 provided at one end of the straight rod portion.
4a is connected and fixed to the electrode 28 of the capacitor 24 with solder 35 so as to close the through hole 26 of the capacitor 24. Further, a washer-shaped electrode connecting body 36 is press-fitted into the through conductor 34 from the opposite direction from the header part 34a with the capacitors 24 and 25 in between, and the electrode connecting body 36 is connected to the through conductor 34 by soldering 37 to the through hole of the capacitor 25. It is connected and fixed to the electrode 31 so that the hole 27 is closed.

In this way, the L-C composite part according to the present invention is
Capacitors 24 and 25 have electrodes 2 on both sides in the thickness direction.
The magnetic body 32 is fitted into the through holes 26 and 27 provided in the thickness direction of the plate, and the through conductor 34 passed through the inside of the magnetic body 32 is connected to the capacitors 24 and 25. Since the structure is electrically connected to the electrodes 28 and 31 provided on one side, unlike the conventional coaxial type L-C composite component shown in Fig. 1, the shrinkage stress of the solder attached to the inner circumferential electrode is Therefore, there is no possibility that cracks will occur in the magnetic material 32 or that the characteristics will be deteriorated due to residual flux.

Moreover, the header portion 34a and the electrode connection body 36
are electrically connected to the electrodes 28 and 31 of the capacitors 24 and 25, respectively, so as to close the through holes 26 and 27 of the capacitors 24 and 25.
The solder 35 and 37 adhering to the header portion 34 and the electrode connection body 36 hardly enters around the magnetic body 32. Therefore, the magnetic material 32 by solder
It is possible to obtain an L-C composite part that does not cause any cracks.

Furthermore, the magnetic body 32 has a cylindrical shape with an axial hole, and is inserted so that most of it is located in the through holes 26 and 27 of the two capacitors 24 and 25. and capacitor 24,2
The total thickness including capacitors 24 and 2 is
5, the overall shape is smaller and thinner.

Reference numeral 38 denotes an external terminal fitting that is electrically connected to the electrodes 29 and 30 of the capacitors 24 and 25, which are stacked on top of each other. In this embodiment, the external terminal fitting 38 is formed into a stepped cylindrical shape, and the assembly of the capacitors 24 and 25 is fitted into the inner diameter part of the small diameter part 38a. The electrodes 29 and 30 of the capacitors 24 and 25, which are superimposed on each other, extend from the surface in the thickness direction to the outer peripheral surface, and have lead electrodes 29a and 30a formed on the outer peripheral surface. And this lead electrode 29a,
30a to the inner diameter surface of the external terminal fitting 38, or by adhering it with a conductive adhesive or the like, the electrode 2
8 and 30 are electrically connected to the external terminal fitting 38. Note that 39 and 40 are insulating resins.

FIG. 6 is an equivalent circuit diagram of the LC composite component according to the present invention described above. As is clear from FIG. 6, the L-C composite component according to the present invention basically has a disk-through type structure, and the through-hole conductor 34 on both sides of the inductance L ₁ by the magnetic body 32 is
One end of each capacitance C ₁ and C ₂ formed by the capacitors 24 and 25 is connected to each other, and the other end of the capacitance C ₁ and C ₂ is commonly connected to an external terminal fitting 38 to form a π-shaped equivalent circuit. Therefore, compared to the conventional example shown in FIG. 3, the characteristics and function as a low-pass filter are significantly improved.

As described above, according to the present invention, the following effects can be obtained.

(a) It is an L-C composite component in which a magnetic material and a capacitor are provided around a through conductor. The magnetic material is inserted into the through hole of the two capacitors, and the mutually stacked electrodes of the two capacitors are electrically connected to the external terminal fittings, and the other capacitors are stacked in series. The two electrodes are electrically connected to a through conductor that passes through the axial hole of the magnetic material in the axial direction, so the π-shaped L-
C. Composite parts can be provided.

(b) A capacitor is constructed by stacking two plate-shaped capacitors in series with electrodes on both sides in the thickness direction with through holes, and the through conductor includes a header part and an electrode connection body. The header part and the electrode connector are electrically connected to the electrodes by closing the through holes on both sides of the capacitor, so there is no cracking or damage to the magnetic material due to shrinkage stress of the solder, and there is no risk of flux. It is possible to provide an L-C composite component that does not suffer from characteristic deterioration due to residue.

(c) The magnetic material is cylindrical with an axial hole, and most of it is inserted into the through holes of the two capacitors, so the entire structure including the magnetic material and the capacitor is It is possible to provide an L-C composite component whose thickness remains the same as that of a capacitor, which is small and thin, and which is effective in improving mounting density and reducing mounting height.

[Brief explanation of the drawing]

Figure 1 is a front sectional view of a conventional L-C composite part.
FIG. 2 is an equivalent circuit diagram thereof, FIG. 3 is a front sectional view of another example of the conventional L-C composite component, FIG. 4 is an equivalent circuit diagram thereof, and FIG. 5 is an L-C composite component according to the present invention. A front sectional view of the C composite component, and FIG. 6 is an equivalent circuit diagram thereof. 24, 25... Capacitor, 26, 27... Through hole, 28-31... Electrode, 32... Magnetic material, 3
4...Through conductor, 38...External terminal fitting.

Claims (1)

[Claims for Utility Model Registration] An L-C composite component in which a magnetic material and a capacitor are provided around a through conductor, the capacitor having a plate shape having electrodes on both sides in the thickness direction in which a through hole is opened. The magnetic body is configured by stacking two capacitors in series, and the magnetic body has a cylindrical shape with an axial hole, and most of the magnetic body is located within the through hole of the two capacitors. The mutually overlapping electrodes of the two capacitors are electrically connected to an external terminal fitting, and the other two electrodes are connected to the through conductor that axially passes through the shaft hole of the magnetic body. The through conductor includes a header portion and an electrode connecting body, and the header portion and the electrode connecting body close the through hole on both sides of the capacitor, and the through conductor is electrically connected to the other capacitor. An L-C composite component characterized by being electrically connected to two electrodes.