JPS633149Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a high-voltage LC composite component used as a line filter for a magnetron tube used in high-frequency, high-power devices, such as microwave ovens.

Recently, high-power electromagnetic waves in the UHF and VHF bands have come to be used not only in industrial equipment such as broadcasting equipment, but also in consumer equipment such as microwave ovens, and as their use increases, leakage from these equipment increases. Noise pollution caused by electromagnetic waves has come to be highlighted as a major social problem. In order to prevent such noise pollution, various line filters have been proposed.

FIG. 1 shows a conventional example of a high voltage LC composite component configured to prevent noise in a magnetron tube. In this conventional example, mutually independent electrodes 2a,
2b and a common electrode 3 are respectively provided,
The common electrode 3 of the dielectric ceramic 1 is fixed by soldering onto the other electrode 5b of a high-voltage ceramic capacitor 5, which has one electrode 5a fixed to the grounding fitting 4 by soldering. Magnetic material 6
One ends 7a, 8a of the coils 7, 8 wound above,
It has a structure in which it is led out by passing through the through holes 1a and 1b, electrically connected to the electrodes 2a and 2b by soldering or conductive adhesive, respectively, and the whole is molded with an insulator 9. The insulator 9 is made of synthetic resin or synthetic rubber in which SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ etc. are uniformly dispersed as a filler, and the grounding fitting 4
Insulating case 10 and insulating bushes 11a, 11
It is formed by casting into b.

In order to use the above-mentioned high voltage LC composite component as a line filter for a magnetron tube in a microwave oven, etc., the coil terminals 7b and 8b of the inductance coils 7 and 8 are respectively connected to the heater 12b of the magnetron tube 12 with the anode 12a grounded. Connect in series. FIG. 2 is an equivalent circuit diagram in that case, where L ₁ and L ₂ are the inductances due to the coils 7 and 8, and C ₁ and C ₂ are the electrodes 2 provided on the dielectric ceramic 1.
The capacitance C ₃ of the feedthrough capacitor formed between a, 2b and the common electrode 3 is the capacitance due to the ceramic capacitor 5.

Normally, only a voltage of several volts is applied to the heater 12b of the magnetron tube 12, but the anode 12
A high voltage of about 500V to 3KV is applied between the heater 12a and the heater 12b. This high voltage has a capacitance of C ₃ and a capacitance of
Shared by C ₁ or C ₂ . In this case, if the relationship between capacitances C ₁ and C ₂ and capacitance C ₃ is selected so that C ₁ = C ₂ ≫ C ₃ , the voltage sharing of the capacitors is inversely proportional to the capacitance value, so the working voltage is 500V to 3KV.
Most of the voltage is added to the ceramic capacitor 5 that constitutes the capacitor C ₃ , and the voltage share of the feedthrough capacitors that constitute the capacitors C ₁ and C ₂ is significantly reduced. As is clear from the specific structure of FIG. 1, increasing the withstand voltage of the feedthrough capacitor is structurally extremely difficult, but increasing the withstand voltage of the ceramic capacitor 5 is relatively easy due to its increased thickness. It can be achieved. Therefore, selecting the relationship among the capacitances C ₁ , C ₂ , and C ₃ such that C ₁ =C ₂ >>C ₃ is structurally consistent.

Moreover, by selecting large values for the capacitances C ₁ and C ₂ , the thickness of the dielectric ceramic 1 can be made thinner, reducing costs and at the same time improving the function as a filter.

In other words, the conventional high-voltage LC composite component shown in Figure 1 has a grounded capacitor connected to the feed-through capacitor, which has the excellent effect of increasing the filter effect and improving dielectric strength at the same time. be able to.

Further, since the grounding capacitor 5 is directly fixed to the grounding metal fitting 4, there is an advantage that the capacitor 5 has a small self-inductance and a high self-resonance frequency.

Furthermore, since the coils 7 and 8 and the capacitors 1 and 5 are integrated and molded within the insulator 9, it is compact and highly reliable, and is easy to install and handle when attached to a magnetron tube, etc. It has the following characteristics.

The present invention does not lose the above-mentioned conventional advantages;
Furthermore, it is an object of the present invention to provide a high voltage LC composite component whose function as a filter is further improved.

In order to achieve the above purpose, high voltage according to the present invention
The LC composite component consists of an inductance coil, a feedthrough capacitor through which a lead wire led from the inductance coil passes through and is fixed to one of the electrodes, and one electrode conductively connected to the other electrode of the feedthrough capacitor and the other electrode. a grounding capacitor fixed on a grounding fitting; a magnetic body passing through the lead wire after passing through the feedthrough capacitor; and a feedthrough capacitor encasing the magnetic substance and fixed to the grounding fitting. It is characterized by

DESCRIPTION OF THE PREFERRED EMBODIMENTS The content of the present invention will be specifically explained in detail below with reference to the accompanying drawings, which are examples.

FIG. 3 is a sectional view of a high voltage LC composite component according to the present invention, and FIG. 4 is an exploded perspective view thereof. In the figure, the same reference numerals as in FIG. 1 indicate the same components. Reference numerals 13 and 14 denote cylindrical magnetic bodies made of ferrite beads, through which lead wires 7a and 8a pass through the dielectric ceramic 1 constituting the feedthrough capacitor.

15 and 16 are feedthrough capacitors made of cylindrical dielectric ceramic, and electrodes 15a, 15b, 16a, and 16b are formed on the inner and outer peripheral surfaces thereof. The feedthrough capacitors 15 and 16 enclose the magnetic bodies 13 and 14, penetrate into the cylindrical portions 4a and 4b provided on the grounding fitting 4, and connect the electrodes 15 on the outer periphery.
b, 16b are fixed to the grounding fitting 4. Further, the electrodes 15a and 16a on the inner circumference are electrically connected to the lead wires 7a and 8a via connectors 17 and 18, respectively.

In the area surrounded by the grounding fitting 4 and the insulating case 19, there is a feedthrough capacitor made of dielectric ceramic 1, a grounding capacitor 5, and magnetic materials 13, 14.
An insulator 9 is filled so as to surround the feedthrough capacitors 15 and 16. The insulator 9 is
As mentioned above, SiO ₂ , Al ₂ O ₃ ,
Constructed of synthetic resin or synthetic rubber in which Fe ₂ O ₃ etc. are homogeneously dispersed.

In this embodiment, the inductance coils 7 and 8 are arranged outside the insulator 9, but they may be molded with the insulator 9.

Furthermore, as shown in FIG. 5, the feedthrough capacitor may be divided into two independent dielectric ceramics 1C and 1D.

Furthermore, the dielectric ceramics 1, 1C, and 1D can be made of semiconductor ceramics to form a semiconductor ceramic feedthrough capacitor. In the case of a semiconductor ceramic capacitor, it is possible to obtain a capacitance 10 times more than that of a dielectric ceramic capacitor, so it is possible to realize a device with a superior noise reduction effect.

FIG. 6 is an equivalent circuit diagram of the high voltage LC composite component according to the present invention. As is clear from the figure, the high voltage LC composite component according to the present invention has a higher inductance L ₃ , C ₄ due to the magnetic bodies 13 and 14 than the conventional high voltage LC composite component shown in FIGS. 1 and 2. It has a structure in which capacitances C ₄ and C ₅ are added by feedthrough capacitors 15 and 16, and the number of filter elements is increased.

Therefore, it is clear that an excellent noise reduction effect can be achieved.

Furthermore, as can be understood from the specific structure shown in FIGS. 3 to 5, the magnetic bodies 13, 14 and feedthrough capacitors 15, 16 are installed by effectively utilizing the conventional dead space. Since there is almost no increase in size or change in the shape, it is possible to realize a compact, efficient, and convenient device for installation and use.

As described above, the high voltage LC composite component according to the present invention includes an inductance coil, a feed-through capacitor through which a lead wire led from the inductance coil is passed, and which is electrically connected to one of the electrodes.
a grounded capacitor in which one of the electrodes is conductively connected to the other electrode of the feedthrough capacitor, and the other electrode is fixed on a grounding fitting; a magnetic body through which the lead wire passes through the feedthrough capacitor; Since the capacitor is characterized by being equipped with a feedthrough capacitor covered with a magnetic material and fixed to the grounding fitting, the part that was conventionally a dead space can be effectively utilized,
It is possible to provide a high voltage LC composite component with improved noise reduction effect without increasing the size or the like.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional high-voltage LC composite component.
Figure 2 is an equivalent circuit diagram when the high voltage LC composite component shown in Figure 1 is used as a filter for a magnetron tube, Figure 3 is a sectional view of the high voltage LC composite component according to the present invention, and Figure 4 is Also an exploded perspective view, No. 5
The figure is a sectional view of another embodiment, and FIG. 6 is an equivalent circuit diagram thereof. 1, 1C, 1D... feedthrough capacitor, 7, 8...
...Inductance coil, 4...Grounding metal fitting, 1
3, 14...Magnetic material, 5...Grounding capacitor, 1
5,16...Feedthrough capacitor.

Claims (1)

[Claims for Utility Model Registration] (1) An inductance coil, a feedthrough capacitor through which a lead wire led from the inductance coil passes and which is fixed to one of the electrodes, and one of the electrodes attached to the other of the electrodes of the feedthrough capacitor. a grounding capacitor that is electrically connected and has the other electrode fixed on a grounding fitting; a magnetic body that is passed through the lead wire after passing through the feedthrough capacitor; A high-voltage device characterized by comprising a feed-through capacitor.
LC composite parts. (2) The high-voltage LC composite component according to claim 1, wherein the magnetic material is made of ferrite beads. (3) The high voltage LC according to claim 1 or 2, wherein the inductance coil, the feedthrough capacitor, and the magnetic body are provided in pairs and share the ground capacitor. Composite parts. (4) The high-voltage LC composite component according to claim 1, 2, or 3 of the utility model registration claim, wherein each component except the inductance coil is embedded in an insulator.