JPS646588Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to an LC filter for use in removing high frequency noise, and more particularly to a filter consisting of a combination of a capacitor and a magnetic core.

Prior Art The conventional noise removing T-type filter shown in FIGS. 1 to 3 forms a ceramic capacitor by providing a dielectric ceramic substrate 1 with a front capacitor electrode 2 and a back capacitor electrode 3. Two inductance elements are constructed by passing a conducting wire 6 through two ferrite hollow cores 4 and 5, that is, bead cores, and a conducting wire 6 is inserted between the two bead cores 4 and 5.
is electrically connected to the capacitor electrode 2 on the front side with solder 7, one end of the conductor 6 is used as the first terminal 6a, the other end as the second terminal 6b, and the lead wire 8 is connected to the capacitor electrode 3 on the back side with solder 9. By combining the third
Terminal 8a is provided. The T-type filter configured as described above has the first terminal 6a as an input terminal, the second terminal 6b as an output terminal, and the third terminal 8a as an input terminal.
is used as a ground terminal, the conducting wire 6 is connected in series to the signal transmission line, and the first bead core 4 is connected to the first inductance element, and the second bead core 4 is connected to the first inductance element.
The core 5 constitutes a second inductance element and is used as an LC noise removal filter.

However, since the dielectric ceramic substrate 1 and the bead cores 4 and 5 are stacked, it has the following drawbacks.

(1) It is difficult to arrange the first to third terminals 6a, 6b, and 8a in a straight line or at predetermined positions.

(2) Assembly is troublesome.

(3) Become large.

(4) Since the capacitor is largely exposed, problems with radio wave radiation will occur.

Purpose of the invention Therefore, the purpose of the present invention is to provide a filter that allows accurate positioning of lead wires, easy assembly, miniaturization, and blocking of radio wave radiation from a capacitor.

In order to achieve the above object, the present invention includes first and second through holes provided in parallel to each other;
a capacitor insertion groove provided between the through hole and the second through hole, and a capacitor insertion groove formed to communicate with the bottom of the groove and extending parallel to the first and second through holes. an insulating magnetic core having at least three through holes; a capacitor inserted into the groove such that one electrode faces the bottom of the groove and the other electrode faces the entrance of the groove; a first lead wire inserted into the third through hole and coupled to the one electrode;
The second lead wire is inserted into the through-holes of the second electrode, and the second lead wire is connected to the other electrode.

Effects of invention According to the above invention, the following effects can be obtained.

(a) A single magnetic core is provided with first to third through holes, and a first lead wire for connecting the capacitor to an external circuit and a second lead wire for obtaining an inductance component are connected to the first through hole. - Since the lead wires are inserted through the third through hole, the mutual positional relationship of the first and second lead wires becomes accurate.

(b) Since the two inductance components of the T-type filter are obtained based on a common magnetic core, and the capacitor is inserted into the groove of the magnetic core, assembly is facilitated. Further, miniaturization becomes possible.

(c) Since the capacitor is inserted into the groove of the magnetic core, radio wave radiation from the capacitor can be restricted.

Embodiment Next, a noise removal filter according to an embodiment of the present invention will be described with reference to FIGS. 4 to 13.

When configuring the filter of this embodiment, first the ferrite core 11, which is an insulating magnetic core shown in FIGS. 4 to 6, and the magnetic capacitor 1 shown in FIG.
2, a first lead wire 13 having a nail head-like portion shown in FIG. 8, and a U-shaped second lead wire 14 shown in FIG. 9 are prepared.

As is clear from FIGS. 4 to 6, the ferrite core 11 is formed into a quadrangular prism shape with six faces, and has first and second through holes 17 and 18 extending from the lower surface 15 to the upper surface 16, and further includes A third through hole 19 is provided between these. Moreover, this core 11
A capacitor insertion groove 20 is provided at the center of the through hole 17 and the second through hole 18, and the first through hole 1
A lead wire fitting groove 21 is provided on the upper surface 16 so as to connect the lead wire fitting groove 7 and the second through hole 18 . Note that the first, second, and third through holes 17, 18, and 19 extend parallel to each other.

As shown in FIG. 7, the capacitor 12 is a plate-shaped capacitor in which one electrode 23 and the other electrode 24 are provided on a dielectric ceramic substrate 22. One electrode 23
is also provided on the bottom surface of the ceramic substrate 22 to facilitate connection to the first lead wire 13, and the other electrode 24 is provided on the top surface of the ceramic substrate 22 to facilitate connection to the second lead wire 14. is also provided.

As shown in FIG. 8, the first lead wire 13 consists of a nail head-shaped part 13a and a lead terminal part 13b,
The nailhead-shaped portion 13a is formed to engage with the bottom of the groove 20. The second lead wire 14 is bent in advance into a U-shape in order to be inserted into the first and second through holes 17 and 18.

When assembling the filter, first attach the first lead wire 1 to the electrode 23 on the bottom surface of the capacitor 12 shown in FIG. 7 with cream solder 25 as shown in FIG.
3 is fixed to the core 11 as shown in FIG.
Attach to. That is, the first lead wire 13 is inserted into the third through hole 19, and the capacitor 12 is inserted into the groove 20.
Insert. The depth of the capacitor insertion groove 20 is set so that the position of the electrode 24 on the upper surface of the capacitor 12 substantially coincides with the bottom of the lead wire insertion groove 21.

Next, the second lead wire 14 shown in FIG. 9 is inserted into the first and second through holes 17 and 18, and the terminal parts 14a and 14b are made to protrude from the core 11 as shown in FIG. is fitted into the groove 21, and the connecting portion 14c is placed on the electrode 24 of the capacitor 12.

Next, the assembly is immersed in a solder bath with the terminal parts 13b, 14a, and 14b facing upward, and the connecting part 14c of the lead wire 14 is connected to the electrode 24 of the capacitor 12 in the 11th position.
They are connected with solder 26 as shown in the figure. This results in
The assembly is completed, but the grooves 20 and 21 may be removed as necessary.
As shown in FIG. 10, the empty space is filled with an adhesive insulator 27 such as synthetic resin, and the lead wire 14 and capacitor 12 are fixed to the core 11. Furthermore, if necessary, it is molded or coated with an exterior paint.

As is clear from the above, this embodiment has the following advantages.

(A) Multiple through holes 17, 18 in a single core 11,
19 is provided, and the second lead wire 14 which becomes the input/output line and the first lead wire which becomes the ground line of the capacitor 12 are inserted through this.
As shown in FIGS. 0 and 13, the three lead terminal portions 13b, 14a, 14b can be accurately and easily arranged on a straight line or in a constant positional relationship.

(B) Since a T-type LC filter consisting of one capacitor and two inductances can be constructed based on the combination of one capacitor 12 and one core 11, assembly work is facilitated.

(C) Since the capacitor 12 is fitted into the groove 20 and the connecting portion 14c of the lead wire 14 is fitted into the groove 21, a stable assembled state can be obtained.

(D) Since the capacitor 12 is embedded in the ferrite core 11, the capacitor 12
is shielded, and capacitor 12
It is possible to reduce unnecessary radio wave radiation from.

(E) Since the connecting portion 14c of the lead wire 14 does not protrude from the core 11, the length of the through holes 17 and 18 that are open to the inductance can be increased if the size is the same as the conventional one. . Moreover, it is possible to make the filter smaller in size compared to the filters shown in FIGS. 1 to 3.

(F) Since the capacitor 12 is embedded within the core 11, mechanical protection of the capacitor 12 is achieved.

(G) The connection between the lead wire 14 and the capacitor 12 can be achieved simply by placing the connecting portion 14c of the U-shaped second lead wire 14 on the upper electrode 24 of the capacitor 12 and soldering it. Therefore, the connection between the two is extremely easy.

Modifications The present invention is not limited to the above-described embodiments, and the following modifications are possible, for example.

(a) As shown in FIGS. 14 to 16, a multilayer ceramic capacitor 12a shown in FIG. 16 may be fitted into the core 11. Note that in FIGS. 14 to 15, parts common to those in FIGS. 4 to 13 are given the same reference numerals. Furthermore, the multilayer capacitor 12a has internal electrodes.

(b) Instead of the capacitor 12, a cylindrical ceramic capacitor, a cylindrical or cylindrical multilayer capacitor may be used.

(c) Although one T-type filter is shown in the example,
A common ferrite core has many through holes,
Multiple T-type filters may be constructed based on a single core.

(d) Connecting part 1 without the lead wire fitting groove 21
4c may be configured to be exposed outside the core 11.

(e) In the embodiment, the capacitor insertion groove 20 is formed in the shape of a hole, and only the top surface is exposed. It may also be a configuration.

(f) The second lead wire 14 may be divided into two lead wires and each lead wire may be connected to the electrode 24 of the capacitor 12.

(g) The entire connection between the electrodes 23 and 24 of the capacitor 12 and the lead wires 13 and 14 may be performed using cream solder or solder dipping.

[Brief explanation of the drawing]

Figure 1 is a plan view of a conventional LC filter, Figure 2 is a front view of the filter in Figure 1, Figure 3 is a right side view of the filter in Figure 1, and Figure 4 is an embodiment of the present invention. A perspective view showing the ferrite core of the filter,
Figure 5 is a plan view of the ferrite core in Figure 4;
The figures are a cross-sectional view taken along the - line in FIG. 5, FIG. 7 is a perspective view of a capacitor according to an embodiment of the present invention, FIG. 8 is a front view of the first lead wire of the embodiment, and FIG. 9 is a diagram of the embodiment. A front view of the second lead wire, Fig. 10 is a sectional view of the completed filter showing the part corresponding to the - line in Fig. 12, and Fig. 11 is a sectional view of the part corresponding to the line XI-XI in Fig. 12. 12 is a plan view showing the filter without solder and filling insulators, FIG. 13 is a bottom view of the filter in FIG. 10, FIG. 14 is a sectional view of a modified filter, and FIG. 14 is a sectional view taken along the line --, and FIG. 16 is a perspective view showing the capacitor of the filter shown in FIG. 14. 11... Ferrite core (magnetic core), 12...
...Capacitor, 13...First lead wire, 14...
...Second lead wire, 17...First through hole, 18
...Second through hole, 19...Third through hole, 20
...Groove for inserting the capacitor, 21...Groove for fitting the lead wire.

Claims (1)

[Claims for Utility Model Registration] (1) First and second through holes provided parallel to each other, and a capacitor insertion groove provided between the first through hole and the second through hole. , and an insulating magnetic core comprising at least a third through hole formed to communicate with the bottom of the groove and extending parallel to the first and second through holes, and one electrode is connected to the groove. a capacitor inserted into the groove so that the other electrode faces the entrance of the groove; and a first electrode inserted into the third through hole and coupled to the one electrode. A filter comprising: a lead wire; and a second lead wire that is inserted through the first and second through holes and coupled to the other electrode. (2) The filter according to claim 1, wherein the magnetic core is a ferrite core. (3) The filter according to claim 1 or 2, wherein the capacitor is a ceramic capacitor.