JP2002050938A - Filter circuit, filter device and lighting device for discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter circuit for reducing the noise below 526.5 kHz. SOLUTION: Normal mode chokes L1 and L2 of an inductance of 10 mH are connected in series via wirings 7 from a commercial AC power supply e. The choke L1 is also connected to one winding Tr1a of a common mode chock Tr1 of total inductance of 10 mH, and the choke L2 to the other windings Tr1b of the chock Tr1. When a fluorescent lamp is high-frequency lighted by a discharge lamp lighting circuit of a ballast, a normal filter circuit reduces noise of frequencies of 526.5 kHz to 30 MHz. A filter circuit 8 reduces noise of frequencies of 9 KHz to 526.5 kHz. The reduction of noise of frequencies such as those that cannot be reduced by the normal filter circuits of the ballast can also handle international standards of the CISPR15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a filter circuit, a filter device, and a discharge lamp lighting device for further suppressing electromagnetic interference.

[0002]

2. Description of the Related Art Conventionally, when a discharge lamp lighting device of this type has an inverter circuit as a discharge lamp lighting device for lighting a discharge lamp at a high frequency, a filter circuit is provided in order to remove noise from the inverter circuit. ing. This filter circuit is regulated by the Electrical Appliance and Material Control Law 526.
Although noise within the range of 5 kHz to 30 MHz is removed, noise at a frequency of 526.5 kHz or less is not removed.

[0003]

However, 52
For frequencies below 6.5 kHz, the international standard CIS
Regulated by PR15, 9kHz to 5
Even at a frequency of 26.5 kHz, there is a problem that medical devices may be affected by electromagnetic interference.

[0004] The present invention has been made in view of the above problems, and has as its object to provide a filter circuit, a filter device, and a discharge lamp lighting device that reduce noise of 526.5 kHz or less.

[0005]

According to a first aspect of the present invention, there is provided a filter circuit comprising: two normal mode chokes each having an inductance of 10 mH or more; and a common mode choke each connected to these two normal mode chokes and having a total inductance of 8 mH or more. And removes noise having a frequency of 9 kHz to 526.5 kHz.

According to a second aspect of the present invention, there is provided a filter circuit comprising: two normal mode chokes each having an inductance of 3 mH or more; a common mode choke each connected to these two normal mode chokes and having a total inductance of 8 mH or more; A ground capacitor having a capacitance of not less than 2200 pF and being connected to either of them, from 9 kHz to 526.5.
Removes noise at a frequency of kHz.

A third aspect of the present invention is a filter circuit comprising two cross-the-line capacitors each having a capacitance of 0.47 μF or more; two cross-line capacitors connected between terminals of these two cross-the-line capacitors and each having an inductance of 0.33 mH or more. With two normal mode chokes;
A common mode choke connected to both ends of one of the cross-over line capacitors and having a total inductance of 8 mH or more; and a grounding capacitor connected to one of the common mode chokes and having an inductance of 2200 pF or more, from 9 kHz to 526. .5k
The noise of the frequency of Hz is removed.

[0008] The filter device according to the fourth aspect is the first aspect.
The filter circuit according to any one of (1) to (3); and a housing for accommodating the filter circuit.

According to a fifth aspect of the present invention, there is provided a filter device which is connected to a discharge lamp lighting circuit for lighting a discharge lamp and attenuates noise in a frequency range of 9 kHz to 526.5 kHz; and a housing for accommodating the filter circuit. And removes noise at a frequency of 9 kHz to 526.5 kHz.

According to a sixth aspect of the present invention, there is provided a discharge lamp lighting device comprising: a discharge lamp lighting circuit for lighting a discharge lamp; a normal filter circuit for removing noise from the discharge lamp lighting circuit; and a discharge lamp lighting circuit and a normal filter circuit. The filter device according to claim 5, wherein the housing is attached to the instrument main body, and the filter device is attached to the instrument main body.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the discharge lamp lighting device according to the present invention will be described with reference to the drawings.

FIG. 1 is a circuit diagram showing a filter circuit, FIG. 2 is an explanatory diagram showing a discharge lamp lighting device, and FIG. 3 is a block diagram showing a discharge lamp lighting device. As shown in FIG. 2, reference numeral 1 denotes a chassis as an instrument body. The chassis 1 has a reflection surface 2 on a lower surface, and a pair of fluorescent lamps 3 and 4 as discharge lamps are mounted on the reflection surface 2. A line insertion hole 5 is formed in the center of the surface 2. A terminal block 6 is disposed near the wire insertion hole 5, and a feed line 7 connected to a commercial AC power supply e is connected to the terminal block 6.

On the back side of the reflecting surface 2, as shown in FIG. 3, 9 kHz to 526.5 kHz of the noise is provided.
Filter circuit 8 shown in FIG.
A filter unit 10 is provided as a filter device housed in a housing 9, and this filter unit 10 is connected to a terminal unit 6 and a filter unit input line 11. Further, a discharge lamp lighting circuit having a discharge lamp lighting circuit (not shown) for lighting the fluorescent lamps 3 and 4 at a high frequency of, for example, 50 kHz or less, and a normal filter circuit for attenuating noise of about 526.5 kHz to 30 MHz from the discharge lamp lighting circuit. A ballast 12 is provided as a device. The ballast 12 is connected to the filter unit 10 via a filter unit output line 13 and supplies power to the fluorescent lamps 3 and 4 via an output line 14. The length of the filter unit input line 11 from the terminal block 6 to the filter unit 10 is made shorter than the length of the filter unit output line 13 from the filter unit 10 to the ballast 12. The noise superimposed on the filter unit is reduced as much as possible to make the filter unit 10 effective.

Further, as shown in FIG. 1, an inductance of 10 mH
As described above, for example, the normal mode choke L1 of 10 mH and similarly the inductance is 10 mH or more, for example, 1
A normal mode choke L2 of 0 mH is connected, the normal mode choke L1 is connected to one winding Tr1a of a common mode choke Tr1 having a total inductance of 8 mH or more, for example, 10 mH, and the normal mode choke L2 is the other of the common mode choke Tr1. The winding Tr1b is connected to the ballast 12 via a filter unit output line 13.

Then, the fluorescent lamps 3 and 4 are turned on at a high frequency by the discharge lamp lighting circuit of the ballast 12, and 52
Attenuates noise at frequencies between 6.5 kHz and 30 MHz.

The filter circuit 8 attenuates noise having a frequency of 9 kHz to 526.5 kHz. In this way, the noise of the frequency that cannot be attenuated by the normal filter of the ballast 12 is attenuated by the filter circuit 8 to comply with the international standard CISPR15 shown in FIG. The risk of giving

Further, the filter unit 10 is separated from the ballast 12, the housing 9 in which the filter circuit 8 is housed is mounted on the chassis 1, and the filter circuit 8 is connected to the feed line 7 by the filter unit input line 11. Ballast with terminal block 6 and filter unit output line 13
Since the filter circuit 8 can be easily attached later electrically and mechanically since the filter circuit 8 can be easily connected later, it can be applied to an existing discharge lamp lighting device.

Next, another embodiment will be described with reference to FIG.

FIG. 5 is a circuit diagram showing a filter circuit according to another embodiment of the present invention.
And a normal mode choke L3 having an inductance of 3 mH or more, for example, 3 mH, and a normal mode choke L4 also having an inductance of 3 mH via a filter unit input line 11, and the normal mode choke L2 has a total inductance of 8 mH or more, for example, 10 mH.
The mH common mode choke Tr2 is connected to one winding Tr2a, the normal mode choke L4 is connected to the other winding Tr2b of the common mode choke Tr2, and the other winding Tr2b of the common mode choke Tr2 has a capacitance of 22 m2.
A grounding capacitor C1 of 00 pF is connected, and is connected to the ballast 12 via a filter unit output line 13.

The filter circuit 8 shown in FIG. 5 attenuates noise having a frequency of 9 kHz to 526.5 kHz as shown in FIG.
It also supports the standard.

Next, another embodiment will be described with reference to FIG.

FIG. 7 is a circuit diagram showing a filter circuit according to another embodiment of the present invention.
And the fuse F through the filter unit input line 11.
And the series circuit of the constant-voltage element Z1
An across-the-line capacitor C2 having a capacitance of 0.47 μF, for example, 0.47 μF, is connected in parallel with Z1. One end of the normal mode choke L5 and one end of a normal mode choke L6 having an inductance of 0.33 mH or more, for example, 0.33 mH, are connected, and a capacitance is connected between the other end of the normal mode choke L5 and the other end of the normal mode choke L6. Is connected to an across-the-line capacitor C3 of 0.47 μF or more, for example, 0.47 μF, and the normal mode choke L5 has a total inductance of 8 mH or more, for example, 10 mF.
The normal mode choke L6 is connected to the other winding Tr3b of the common mode choke Tr3, and the other winding Tr3b of the common mode choke Tr3 has a capacitance of 22 mH.
A grounding capacitor C4 of 00 pF is connected to the ballast 12 via a filter unit output line 13.

The filter circuit 8 shown in FIG. 7 attenuates noise having a frequency of 9 kHz to 526.5 kHz as shown in FIG.
It also supports the standard.

[0024]

According to the filter circuit of the first aspect,
Noise at a frequency of 9 kHz to 526.5 kHz can be removed.

According to the filter circuit of the second aspect, 9
Noise at a frequency of kHz to 526.5 kHz can be removed.

According to the filter circuit of the third aspect, 9
Noise at a frequency of kHz to 526.5 kHz can be removed.

According to the filter device of the fourth aspect, since the housing for accommodating the filter circuit of any one of the first to third aspects is provided, the respective effects can be obtained.

According to the filter device of the fifth aspect, 9
Noise at a frequency of kHz to 526.5 kHz can be removed.

According to the discharge lamp lighting device of the sixth aspect,
Each effect can be obtained by attaching the filter device to the instrument body.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of a filter circuit of the present invention.

FIG. 2 is an explanatory diagram showing a discharge lamp lighting device according to the first embodiment;

FIG. 3 is a block diagram showing a discharge lamp lighting device according to the first embodiment;

FIG. 4 is a graph showing the relationship between the frequency and the gain of the international standard CISPR15.

FIG. 5 is a circuit diagram showing a filter circuit according to another embodiment of the present invention;

FIG. 6 is a graph showing attenuation characteristics of the filter circuit shown in FIG. 5;

FIG. 7 is a circuit diagram showing a filter circuit according to another embodiment of the present invention;

8 is a graph showing an attenuation characteristic of the filter circuit shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chassis as a fixture main body 3, 4 Fluorescent lamp as a discharge lamp 8 Filter circuit 9 Housing 10 Filter unit as a filter device 12 Ballast as a discharge lamp lighting device C1, C4 Ground capacitor C2, C3 Across the line capacitor L1 , L2, L3, L4, L5, L6 Normal mode choke Tr1, Tr2, Tr3 Common mode choke

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenichi Asami 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Inside Toshiba Lighting & Technology Corporation (72) Inventor Keiji Takahashi 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation (72) Inventor Fumio Kamiya 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting-Tech Corporation (72) Inventor Toshiyuki Hiraoka 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Inside (72) Inventor Kazuhiko Furuya 4-33, Shibaura, Minato-ku, Tokyo Kannai Kogyo Co., Ltd. (72) Inventor Katsumi Mizuno 4-83, Shibaura 4-chome, Minato-ku, Tokyo 72) Inventor Shigeka Sakai 4-33 Shibaura, Minato-ku, Tokyo Inside Kandenko Co., Ltd. (72) Inventor Toshio Ishizaki 4-chome, Shibaura, Minato-ku, Tokyo Ban No. 33 Kandenko Co., Ltd. in the F-term (reference) 3K072 AA01 FA05 GB01 5E058 AA40 5H740 BB08 NN02 PP02 5J024 AA01 DA25 EA09 FA04

Claims (6)

[Claims] 1. A filter circuit comprising: two normal mode chokes each having an inductance of 10 mH or more; and a common mode choke each connected to these two normal mode chokes and having a total inductance of 8 mH or more. 2. Two normal mode chokes each having an inductance of 3 mH or more; a common mode choke each having a total inductance of 8 mH or more connected to each of the two normal mode chokes; and a capacitance connected to any one of the common mode chokes. 22
A grounding capacitor of at least 00 pF. 3. The capacitance is 0.47 μF each.
The above two cross-the-line capacitors;
Two normal mode chokes connected between the terminals of one cross-the-line capacitor and each having an inductance of 0.33 mH or more; common-mode chokes connected to both ends of one of the cross-line capacitors and having a total inductance of 8 mH or more; 220 connected to one of the common mode chokes with an inductance of 220
A grounding capacitor of 0 pF or more. 4. A filter device comprising: the filter circuit according to claim 1; and a housing for housing the filter circuit. 5. A filter circuit connected to a discharge lamp lighting circuit for lighting a discharge lamp, the filter circuit attenuating noise in a frequency range of 9 kHz to 526.5 kHz; and a housing accommodating the filter circuit. Filter device. 6. A discharge lamp lighting circuit for lighting a discharge lamp; a normal filter circuit for removing noise from the discharge lamp lighting circuit; an appliance body for accommodating the discharge lamp lighting circuit and the ordinary filter circuit; A discharge lamp lighting device, comprising: a filter device according to claim 5, wherein a housing is attached.