JPS59212014A - Noise filter - Google Patents

Abstract

PURPOSE:To form a noise filter without using any magnetic core by winding a beltlike conductor and a beltlike magnetic conductor with a beltlike insulator between. CONSTITUTION:The beltlike conductor 6 made of aluminum foil which is, for example, 12mm. wide and 20mum thick and the beltlike magnetic conductor 9 made of iron foil which is 12mm. wide and 20mum thick are wound in a tubular shape while two Mylar tapes 11 which are 15mm. wide and 57mum thick are interposed so that a hollow core which has a 4mm. diameter is left at the center part. Consequently, the electrostatic capacity is as large as that of a filter constituted merely by using only good conductors made of aluminum foil, but the inductance is more than twice. Thus, a superior element as a noise filter is obtained by using the magnetic conductive foil as the conductive foil of a tubular capacitor without using any magnetic core.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a noise filter that is connected to a power supply circuit or a smoothing circuit and used to suppress noise and pulsation components.

Noise filters are used to prevent equipment from malfunctioning due to noise superimposed on the power supply, and to prevent noise generated by the equipment from being emitted to other equipment or the power supply side. There is.

Izuwa, even if we consider the purpose of noise filter 1, the first
As shown in the figure, a circuit in which an inductance (L) is inserted in series with a power supply and a capacitor (C) is connected in parallel has been widely used as a noise filter.

The inductance (L) used in such a noise filter circuit is made of a toroidal ferrite core or a bead-shaped magnetic core (4) having a hole (3) through it, as shown in Figure 2(a). ) with a conducting wire (5) inserted through the hole.

In order to manufacture the inductance (L) used in such a noise filter circuit, it is necessary to go through the molding/sintering process of the magnetic core material and the winding process, and also to connect the capacitor (C). Therefore, the present invention was devised to solve such problems and obtain an inexpensive noise filter. A capacitor wound in a tubular shape can also function as a coil without using a coil.
This capacitor is constructed to increase inductance by using a strip-shaped magnetic conductor such as iron foil as the electrode material of the capacitor.

As shown in Figure 3, lead wires (7) and (8) are placed near both ends of a strip-shaped conductive material (6) such as copper foil or aluminum foil.
Connect the lead wire (10) to the strip-shaped magnetic conductor (9) such as iron foil, and then connect the strip-shaped good conductor (6) and the strip-shaped magnetic conductor (9) to a strip-shaped magnetic conductor (9) such as capacitor paper. The noise filter element (12) of the present invention is produced by overlapping the strips with a strip-shaped insulator (11) such as an insulating sheet interposed therebetween, and then rolling them into a tubular shape as shown in FIG.

The lead wire (7) at one end of the strip-shaped good conductor (6) forming this noise filter element (12) and the lead wire (7) at the other end
8), and since the strip-shaped good conductor (6) forming this coil is sandwiched between the strip-shaped magnetic conductor (9), the inductance increases.
Moreover, since the capacitors are formed in a distributed manner over the entire structure, a noise suppressing effect can be exhibited.

In particular, by making the width (1) of the strip-shaped good conductor (6) narrower than the width (t') of the strip-shaped magnetic conductor (9), when rolled into a tubular shape, the strip-shaped good conductor (
6) can be obtained by burying it in a magnetic material,
Inductance can be increased.

(A) As shown in Figure 2 (b), the major axis is 67 mm and the minor axis is 3 mm.
I connected a paper capacitor (C) sold by TDK Corporation with a height of 4.8 mm as shown in Figure 1 and measured the relationship between frequency and attenuation rate, and found that the dotted line (A) in Figure 5
) exhibited the characteristics shown below.

On the other hand, (B) the strip-shaped good conductor (6) has a width of 9 mm and a thickness of 70 mm.
When we measured the relationship between the frequency and the attenuation rate for the noise filter element of the present invention, which employs micron aluminum foil and has a capacitance of a band-shaped magnetic conductor of μF, we found that it had an excellent result as shown by the solid line (B) in Figure 5. Characteristics comparable to those indicated by the dotted line (A) were obtained.

As explained above, according to the noise filter of the present invention, an element having an excellent function as a noise filter can be obtained simply by deforming a tubular capacitor, so it is suitable for mass production and can be manufactured at low cost. be able to.

Note that the inductance (L) and capacitor (C) can be adjusted by adjusting the width and length of the coil and capacitor portions of the strip-shaped conductor that form this noise filter element, respectively. By connecting coils in series and adding more windings to increase the inductance (L), it is possible to obtain the desired performance required.

Further, as a measure to prevent leakage of magnetic flux from this noise filter element, it may be inserted into a case made of ferromagnetic material, or the outer periphery may be solidified with ferromagnetic powder.

The noise filter of the present invention can also be applied to a smoothing circuit to suppress pulsating components contained in a power supply.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventionally known noise filter circuit, FIG. 2 is a perspective view of an inductance element used in the circuit of FIG. FIG. 4 is a perspective view of a noise filter of the present invention, and FIG. 5 is a perspective view of a conventional noise filter.
FIG. 3 is a characteristic curve diagram showing the characteristics of a filter and a noise filter of the present invention. 6......Strip-shaped conductor 9...Strip-shaped magnetic conductor/σ 7.8, 〆...Lead wire 11...
... Band-shaped insulator (fLP) 4 ” $ : V' Procedural amendment (July 1982) Kazuo Wakasugi, Commissioner of the Japanese Patent Office 1, Case indication patent application No. 1985-085925 2, Name of the invention Noise filter 3, relationship with the case of the person making the amendment Patent applicant address 2-5-6-2135 Sanno, Ota-ku, Tokyo Claims column of the specification to be amended Both ends of the claims A strip-shaped conductor such as aluminum foil with a pair of lead wires connected near the part and a strip-shaped magnetic conductor such as iron foil are wrapped in a Ziegler shape through a strip-shaped insulator such as an insulating sheet, and the strip-shaped conductor is A noise filter formed by a coil having distributed capacitance together with the above-mentioned strip-shaped magnetic conductor.Procedural amendments, 1981, 10 Months and Months, Commissioner of the Japan Patent Office, Kazuo Wakasugi, 1, Patent Application for Indication of Case, 1982- 085925 No. 2, Title of the invention Noise filter 3 Relationship with the case of the person making the amendment Patent applicant 5, Full text of the specification to be amended and Figure 6 of the drawings Description 1, Title of the invention Noise filter 2, Patent Claims: Current-carrying conductive winding with connected K#!LD wire near both ends!
A noise filter formed by forming the above-mentioned strip-shaped conductor together with the above-mentioned strip-shaped magnetic conductor into a coil having distributed capacitance. 3. Detailed Description of the Invention The present invention relates to a noise filter that is connected to a power supply circuit or a smoothing circuit and used to suppress noise and pulsation components. Noise filters are used to prevent equipment from malfunctioning due to noise superimposed on the power supply, and to prevent noise generated by the equipment from being emitted to other equipment or the power supply side. There is. For any purpose of noise filling, as shown in Figure 1, an inductor /((
Conventionally, a circuit in which a capacitor (C) is inserted and a capacitor (C) is connected in parallel has been widely used as a noise filter. The inductance (L) used in such a noise filter circuit is determined by connecting a magnetic core (1) such as a toroidal ferrite core or a dust core to a coil (2) as shown in Figure 2(a). ), or a bead-shaped magnetic core (4) with a through hole (3) as shown in Figure 2(b), with a conducting wire (5) inserted through the hole. There is. In order to manufacture the inductance (L) used in such a noise filter circuit, it is necessary to go through the molding/sintering process of the magnetic core material and the winding process, and also to connect the capacitor (C). There was a problem in that the processing costs increased because of the need to do so. Therefore, this invention was devised in order to solve these problems and obtain an inexpensive noise filter. Connect the lead wires (7) and (8) near both ends of the strip-shaped conductive material (6) such as copper foil or aluminum foil, and then connect the lead wires (7) and (8) to the strip-shaped magnetic conductor (9) such as iron foil. The wires (lO) are connected, and the strip-shaped good conductor (6) and strip-shaped magnetic conductor (9) are overlapped with a strip-shaped insulator (l l) such as an insulating sheet such as capacitor vapor interposed, and As shown in Fig. 4, the noise filter is composed of an element (12) that is wound into a tubular shape and has capacitance distributed over the entire coil.This noise filter element (12) A coil is formed between the lead wire (7) at one end of the strip-shaped good conductor (6) forming the coil and the lead wire (8) at the other end, and the strip-shaped good conductor forming the coil Since the body (6) is sandwiched between the strip-shaped magnetic conductors (9), the inductance increases, and capacitance is formed in a distributed constant manner over the entire body. ) and (9) are inductively coupled to each other, so they can exhibit a noise suppressing effect. In particular, the width (1) of the strip-shaped good conductor (6) can be compared to the width (1) of the strip-shaped magnetic conductor (9). narrower than the width (t') of (by doing so, when rolled into a tubular shape, an effect similar to that of burying the strip-shaped conductive material (6) in a magnetic material can be obtained, increasing the inductance. (A) As shown in Fig. 2 (b), the long axis is 6 mm, the short axis is 3 mm, and the height is 48 mm.It is made from the heath-like core of [ZBF253D-01J] sold by TDK Corporation. When the inductance (L) and the paper capacitor (C) of approximately 0.01 μF were connected as shown in Figure 1, the termination was opened and the relationship between frequency and attenuation rate was measured.
It exhibited the characteristics shown by the dotted line (A) in the figure. On the other hand, (B) an aluminum foil with a width of 9 mm and a thickness of 70 microns is adopted as the strip-shaped good conductor (6), and an iron foil with a width of 9 mm and a thickness of 20 microns is adopted as the strip-shaped magnetic conductor (9). Adopts foil and wraps it 36 times.
The noise filter element of the present invention, which has a capacitance of about 0.01 μF, which is the same as that in (A) above, was opened at the terminal end and the relationship between the frequency and the attenuation rate was measured. ), and the properties comparable to those of point 1(A) were obtained. The measured values of (A) l (B) explained above are all values with the output side terminal open, but J I
According to the S-C6904-1977 symmetric interference wave voltage prevention effect test circuit, a 50Ω non-inductive resistor was connected to the output terminal, and each of the above noises (A) and (B) was tested.
When the filter element was similarly measured, it exhibited the characteristics shown in FIG. 6 (A) and (B). As explained above, according to the noise filter of the present invention, it is possible to obtain an element with excellent functions as a noise filter by simply transforming a tubular capacitor, making it suitable for mass production and inexpensive to manufacture. can do. Note that the inductance (L) and capacitor (C) can be adjusted by adjusting the width and length of the coil and capacitor portions of the strip-shaped conductor that form this noise filter element, respectively. The required desired performance can be obtained by connecting coils in series and adding additional windings to increase the inductance (L). The noise filter of the present invention can also be applied to a smoothing circuit to suppress pulsating components contained in a power supply. 4. Brief explanation of the drawings Fig. 1 is a circuit diagram of a conventionally known noise filter circuit, Fig. 2 is a perspective view of an inductance element used in the circuit of Fig. 1, and Fig. 3 is a diagram of a noise filter circuit according to the present invention. FIG. 4 is a perspective view of the noise filter manufacturing process, FIG. 4 is a perspective view of the noise filter of the present invention, and FIGS. 5 and 6 show the characteristics of the conventional noise filter and the noise filter of the present invention. FIG. 6......Strip-shaped conductor 9...Strip-shaped magnetic conductor 7 + 8 + I O...
Lead wire 6- 11... Band-shaped insulator 12... Noise filter 7- ('W)3$'? Written amendment of territorial proceedings March 27, 1980 Kazuo Wakasugi, Commissioner of the Japan Patent Office Mr. L Display of the case Patent application No. 1985-085925 2, Name of the invention Noise filter a Person making the amendment Relationship with the case Patent applicant & amendment The entire text of the subject specification and Figures 5 to 8 of the drawings 6 Contents of the amendment As shown in the appendix Description L Name of the invention Noise filter 2, Claims A current-carrying conductor with lead wires connected near both ends A strip-shaped conductor and a strip-shaped magnetic conductor are wound into a tubular shape through a strip-shaped insulator such as an insulating sheet, and the strip-shaped conductor and the strip-shaped magnetic conductor are formed into a coil having a distributed electric charge. noise filter. 3. Detailed Description of the Invention The present invention relates to a noise filter that is connected to a power supply circuit or a smoothing circuit and used to suppress the propagation of noise and pulsating components. Noise filters are used to prevent equipment from malfunctioning due to noise superimposed on the power supply, and to prevent the noise generated by the equipment from being transmitted to other equipment or the power supply side. There is. h. Regardless of the purpose of noise fill, 1- As shown in Figure 1, inductance (L
) and a capacitor (C) connected in parallel have been widely used as noise filters. The inductance (L) used in such a noise filter circuit is determined by connecting a magnetic core (1) such as a toroidal ferrite core or a dust core to a coil (2) as shown in Figure 2(a). ), or a bead-shaped magnetic core (4) with a through hole (3) as shown in Figure 2(b), with a conducting wire (5) inserted through the hole. There is. In order to manufacture the inductance (L) used in such a noise filter circuit, it is necessary to go through the molding/sintering process of the magnetic core material and the winding process, and also to connect the capacitor (C). There was a problem in that the processing costs increased because of the need to do so. Therefore, this invention was devised in order to solve such problems and obtain an inexpensive noise filter, as shown in FIG. , leads near both ends of a strip-shaped good conductor (6) such as copper foil or aluminum foil.
Band-shaped insulators such as paper-like insulating sheets (11)
The noise filter is composed of an element (12) which is superimposed with a coil interposed therebetween and then wound into a tubular shape as shown in FIG. 4, so that the entire coil has a distributed capacitance. A coil is formed between the IJ lead wire (7) at one end of the band-shaped good conductor (6) that forms this noise filter element (12) and serves as a current-carrying conductor and the lead wire (8) at the other end. Moreover, the strip-shaped good conductor (6) that forms this coil
is sandwiched between the strip-shaped magnetic conductors (9), so the inductance increases, and capacitance is formed in a distributed constant manner over the entire area, and the two strip-shaped conductors (9)
Since elements 6) and (9) are inductively coupled, they can exhibit a noise suppressing effect. Next, the attenuation characteristics of the noise filter of the present invention,
That is, the relationship between frequency and attenuation rate will be explained in comparison with a conventional noise filter. The noise filter that we prototyped in order to obtain the measured values of such attenuation characteristics has a conventional row (h) as shown in Figure 2 (b), which has a major axis of 6 mm, a minor axis of 3 mm, and a conventional noise filter for comparison.
rZBF'253D- (made with a bead-shaped core of 1 tJ and has an inductance (L) of approximately 0, ..., OLl μF) sold by TDK Corporation with a height of 4.8 m
of! The capacitor (C) is connected as shown in Figure 1, and the conventional row (B) is made of two strip-shaped conductors - 12 ifi in width and 20 microns in thickness without using any magnetic material. 2 sheets c7) 2 sheets of Mylar aluminum foil with a width of 15 strips and a thickness of 57 microns.
(B-1)) Two pieces of aluminum foil, 50cm long, were wrapped 17 times through a tape, leaving an empty core with a diameter of 4mm in the center. (B-2) As two sheets of aluminum foil, length lO. (B-3) Two pieces of aluminum foil wrapped around 150 m long aluminum foil 38 times; Example foil used as a strip-shaped magnetic conductor (9) Using iron foil with a width of 12 mm and a thickness of 20 microns, a wire with a diameter of 4 m in the center was placed between two pieces of Mylar tape 15 mm wide and 57 microns thick.
(C-1) One aluminum foil and one iron foil each having a length of 50 m are rolled into a tubular shape, leaving an empty core of 50 m long.
(C-2) Aluminum foil and iron foil each having a length of 1ooCrn are rolled 28 times. 5- (C-3) Aluminum foil and iron foil wrapped 38 times, each having a length of 150 cy. These prototype noise filters (B-1) to (B-3
) and the noise filters (C-■) to (C
The electrical characteristics of -3) are shown in Table 1. 6- In Table 1, as is clear from the comparison of the same number of turns, the noise filter of this invention (C -1)～
(C-3) is a noise filter (B-t) ~ (B-
It can be seen that the inductance and Q are larger than in 3), and the capacitance is almost equal. Next, for each of the above prototype noise filters, the relationship between frequency and attenuation rate is determined according to J I 5-C69n4-19.
According to the test circuit for the prevention effect against symmetrical interference wave voltage of No. 77, a 50Ω non-inductive resistor was connected to the output terminal and the measured values shown in the characteristic curve diagrams in Figures 5 to 8 were obtained. It was done. In addition, the symbols written alongside each characteristic curve in the figure indicate the difference in attenuation characteristics based on the difference in the material of the strip conductor (aluminum foil and aluminum foil, aluminum 7M and iron foil), as explained above. It can be seen that the noise filter of the present invention using iron foil in combination exhibits excellent attenuation characteristics over a wide frequency band. FIG. 8 shows the difference in attenuation characteristics based on the number of turns of the noise filter C of the present invention, which uses aluminum foil and iron foil as the strip-shaped conductor. It can be seen that the attenuation rate increases over the frequency band, and exhibits a tendency for the attenuation rate to increase particularly in the low frequency band. For reference, the attenuation characteristics of the noise filter that combines an inductance and a capacitor in the conventional example (A) are shown in the eighth example.
It is shown by curve (A) in the figure. As explained above, according to the noise filter of the present invention, an element having an excellent function as a noise filter can be obtained by modifying a tubular capacitor and using iron foil as a strip-shaped conductor. This makes it suitable for mass production and can be manufactured at low cost. In addition, as each strip-shaped conductor, metallized paper
As in the case of capacitors, miniaturization and mass production are facilitated by wrapping metallized paper on which aluminum or iron is deposited by vapor deposition or plating around the insulating sheet. In the noise filter 3 of the present invention, it is possible to obtain the desired performance by adjusting the width and the number of windings (length) of the conductor strips and adjusting the inductance and capacitance. Furthermore, the cross-sectional area of the strip-shaped good conductor to which electricity is applied should be determined in consideration of the allowable current flow, unlike the cross-sectional area of other strip-shaped breakable conductors. The noise filter of the present invention can also be applied to a smoothing circuit to suppress pulsating components contained in a power supply. 4. Brief explanation of the drawings Fig. 1 is a circuit diagram of a conventionally known noise filter circuit, Fig. 2 is a perspective view of an inductance element used in the circuit of Fig. 1, and Fig. 3 is a diagram of a noise filter circuit according to the present invention. FIG. 4 is a perspective view of the noise filter of the present invention, and FIGS. 5 to 8 show the differences between the conventional noise filter and the =IO− noise filter of the present invention. It is a characteristic curve diagram showing characteristics. 6......Strip-shaped good conductor 9...Strip-shaped magnetic conductor 7 +8.10...Lead wire 11...
...... Band-shaped insulator 12 ...... Noise filter ll-

Claims (1)

[Claims] Distributed capacitance is created by wrapping a band-shaped conductor such as a conductor foil with a pair of lead wires connected near both ends and a band-shaped magnetic conductor such as iron foil into a tubular shape through a band-shaped insulator such as an insulating sheet. A noise filter formed on a coil.