JP2001016061A - Filter circuit, discharge lamp turn-on device, and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the discharge lamp turn-on device which removes noise corresponding to a floating capacity. SOLUTION: A filter circuit 13 is connected to a commercial AC power source (e) via a terminal 12 and the filter circuit 13 has a capacitor C1, a common mode choke Tr1, a normal mode choke L1, a capacitor C2, a ground capacitor C3, and a ground capacitor C4. The input terminal of a full-wave rectifier 15 is connected to the filter circuit 13, an inverter circuit 16 is connected to the output terminal of the full-wave rectifier 15, and a fluorescent lamp FL is connected to the inverter circuit 16. The beginning of the coil of the normal mode choke L1 is positioned on the side of the inverter circuit 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter circuit for suppressing noise, a discharge lamp lighting device, and a lighting device.

[0002]

2. Description of the Related Art Generally, in a discharge lamp lighting device, a filter circuit is connected to a commercial AC power supply via a terminal, and an inverter circuit connected to a discharge lamp via a rectifier circuit is connected to the filter circuit. Also, the filter circuit
It has a common mode choke, a normal mode choke, a ground capacitor, and the like.

After the voltage of a commercial AC power supply is rectified by a rectifier circuit, the voltage is converted into a high-frequency AC by an inverter circuit, and the discharge lamp is lit at a high frequency. In the filter circuit, noise generated in the inverter circuit is removed and harmonics are prevented from flowing to the power supply side.

[0004]

However, there is a problem that noise cannot be sufficiently removed due to stray capacitance such as a common mode choke, a normal mode choke, and a ground capacitor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a filter circuit, a discharge lamp lighting device, and a lighting device for removing noise corresponding to stray capacitance.

[0006]

According to a first aspect of the present invention, there is provided a filter circuit comprising a normal mode choke connected between a power supply and a load and having a winding start connected to a load side.
By setting the winding start side to be a load side that is a noise source, stray capacitance can be reduced, and noise returning to the power supply side can be suppressed.

According to a second aspect of the present invention, there is provided a filter circuit.
In the filter circuit described above, the normal mode choke is one in which the winding start side can be seen from the outside, and knowing the winding start from the outside can surely make the winding start on the load side.

According to a third aspect of the present invention, there is provided a filter circuit comprising: a grounding capacitor; a choke connected to the power supply side from the grounding capacitor; and a grounding capacitor disposed near the choke and shielding at least a part of the choke. A metal body grounded to the load side from the grounding portion,
Noise generated by the choke is electrostatically shielded by a metal body and grounded on the load side, which is a noise source, from a grounding capacitor, thereby suppressing noise returning to the power supply side.

According to a fourth aspect of the present invention, there is provided a filter circuit comprising: a grounding capacitor; a choke connected to the power supply side from the grounding capacitor; and a grounding capacitor disposed near the choke and shielding at least a part of the choke. A magnetic material grounded to the load side from the grounding portion,
Noise generated by the choke is electrostatically shielded by a magnetic material and grounded on the load side, which is a noise source, from a grounding capacitor, thereby suppressing noise returning to the power supply side.

A filter circuit according to a fifth aspect of the present invention includes a terminal connected to the power supply side; a grounding capacitor; a filter disposed near the terminal, at least a portion of the terminal being shielded, and a load side of the grounding portion of the grounding capacitor. And a metal body grounded to the ground, the noise generated at the terminal is electrostatically shielded by the metal body and grounded on the load side that is a noise source from the grounding capacitor,
Suppress noise returning to the power supply side.

A filter circuit according to a sixth aspect of the present invention is a filter circuit, comprising: a terminal connected to a power supply; a grounding capacitor; a filter disposed near the terminal; With a magnetic material grounded to the terminal, noise generated at the terminal is electrostatically shielded with a magnetic material, and grounded on the load side which is a noise source from a grounding capacitor,
Suppress noise returning to the power supply side.

According to a seventh aspect of the present invention, there is provided a discharge lamp lighting apparatus comprising: an inverter circuit serving as a load for lighting the discharge lamp; and a power supply and the filter circuit according to any one of the first to sixth aspects connected between the inverter circuits. What did
Each function is performed.

According to an eighth aspect of the present invention, there is provided an illuminating apparatus comprising: the discharge lamp lighting apparatus according to the seventh aspect; and a fixture body on which a discharge lamp to be lit by the discharge lamp lighting apparatus is mounted. To play.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a lighting device according to an embodiment of the present invention.

FIG. 1 is a circuit diagram showing one embodiment of a discharge lamp lighting device, and FIG. 2 is a perspective view showing the appearance of a lighting device.

As shown in FIG. 2, a reflecting surface 2 is formed on the lower surface of the apparatus main body 1, and lamp sockets 3 and 3 are provided at both ends of the reflecting surface 2, with a space between the lamp sockets 3 and 3. A fluorescent lamp FL as a discharge lamp is provided, and a discharge lamp lighting device 11 is housed inside the appliance body 1.

In this discharge lamp lighting device 11, as shown in FIG. 1, a filter circuit 13 is connected to a commercial AC power supply e via a terminal 12, and this filter circuit 13 comprises a capacitor C1, a common mode choke Tr1, a normal Mode choke L1, capacitor C2, ground capacitor C3 and ground capacitor C4
Are connected and formed.

The input terminal of a full-wave rectifier 15 as a rectifier circuit is connected to the filter circuit 13.
The output terminal 15 is connected to an inverter circuit 16 as a load, and the inverter circuit 16 is connected to a fluorescent lamp FL.

The winding of the coil of the normal mode choke L1 is located on the inverter circuit 16 side. Here, as shown in FIGS. 3 and 4, the normal mode choke L1 has dummy legs 23, 22 in addition to the electrical connection legs 21, 22 so that the winding start and the winding end can be distinguished structurally. By disposing the legs 21, 22, and 23 in a state other than the vertices of an equilateral triangle, for example, an isosceles triangle, the legs 21, 22, and 23 are mounted on the board on which the normal mode choke L1 is mounted.
The winding start side of the coil of the normal mode choke L1 can be reliably connected to the inverter circuit 16 side only by forming and aligning the insertion holes corresponding to 22 and 23, so that the connection cannot be made unless the direction is correct. Things.

Next, the operation of the above embodiment will be described.

First, the voltage of the commercial AC power supply e is applied to a full-wave rectifier.
Full-wave rectification is performed at 15 and converted to a high-frequency AC voltage by the inverter circuit 16 to turn on the fluorescent lamp FL at high frequency.

At this time, the filter circuit 13 suppresses the noise generated in the inverter circuit 16 from returning to the commercial AC power supply e.

The experimental results of noise when the winding of the coil of the normal mode choke L1 is connected to the commercial AC power supply e and when it is connected to the inverter circuit 16 are as follows.
As shown in Table 1, in each case, the noise can be suppressed when the winding start of the coil of the normal mode choke L1 is on the inverter circuit 16 side.

[0024]

[Table 1] Here, the reason why noise can be suppressed when the winding of the coil of the normal mode choke L1 is on the inverter circuit 16 side will be described.

First, the discharge lamp lighting device 11 shown in FIG. 1 is simplified to the circuit shown in FIG. 5 by short-circuiting the common mode choke Tr1 for easy analysis.

In the simple circuit shown in FIG. 5, as shown in FIG. 6, the ground capacitance is CS, the resistance assuming that a leakage current flows is Rx, the inverter circuit 16 is a high frequency power supply eHf, and the commercial AC power supply eHf is used. Think about it. At this time, as shown in FIG. 6, a current flows through the path of the high-frequency power supply eHf, the normal mode choke L1, the capacitor C1, and the high-frequency power supply eHf, and the high-frequency power supply eHf, the normal mode choke L1, the capacitor C1, the ground capacitance CS, Resistance R
A leakage current flows through the path of x and the high frequency power supply eHf.

Then, as shown in FIG. 7, when the winding start side of the normal mode choke L1 is set to the commercial AC power supply e side,
The stray capacitances Cf1 to Cfn are present, and a large leak current flows through the stray capacitance Cfn as shown in FIG. 8, and conversely, the winding start side of the normal mode choke L1 is connected to the inverter circuit 16 as shown in FIG. On the side, there are stray capacitances Cf1 to Cfn, and as shown in FIG. 10, only a small leak current flows through the stray capacitance Cfn, so that the leak current can be suppressed and noise can be suppressed. It is considered that this may be achieved by connecting the winding start side of the normal mode choke L1 to the unstable potential side.

Next, a normal mode choke L1 according to another embodiment will be described.

First, as shown in FIG. 11, one leg 21 of the normal mode choke L1 is made thicker with respect to the other leg 22, and the insertion hole of the board on which the normal mode choke L1 is mounted is also formed by these legs 21, 21. Normal mode choke with correct polarity by positioning and inserting if it corresponds to 22 thickness
L1 can be installed.

As shown in FIG. 12, one leg 21 of the normal mode choke L1 is made longer by the other leg 22, and the insertion hole of the board on which the normal mode choke L1 is mounted is also formed by these legs 21 and 21. If it is set to a depth corresponding to the length of 22, the normal mode choke L1 can be installed with the correct polarity by positioning and inserting, and if the insertion holes are the same depth or if both sides are open, visual The normal mode choke L1 can be mounted with the correct polarity.

Further, as shown in FIG. 13, even when the legs 21 and 22 of the normal mode choke L1 are the same, a marking 24 is formed on the winding start side of the coil, for example.
The normal mode choke L1 can be attached with the correct polarity by visually judging.

Next, a discharge lamp lighting device according to another embodiment will be described with reference to FIGS.

The discharge lamp lighting device 11 shown in FIG. 14 is different from the discharge lamp lighting device 11 shown in FIG. 1 in that the normal mode choke L1 of the circuit board 30 on which the normal mode choke L1 is mounted as shown in FIG. , A metal plate 31, which is a metal body for electrostatic shielding, is attached to the ground, and the metal plate 31 is grounded to the AC output terminal of the full-wave rectifier 15 on the inverter circuit 16 side from the grounding capacitors C3 and C4. .

As described above, the metal plate 31 is attached near the normal mode choke L1, and the metal plate 31 is connected to the full-wave rectifier.
By grounding to the 15 AC output terminal, the leakage current from the normal mode choke L1 is induced through the metal plate 31 to the side of the inverter circuit 16 which is a noise source, and again the filter circuit
13 to prevent the noise from directly returning to the commercial AC power supply e as it is, thereby suppressing the noise.

Another embodiment will be described with reference to FIG.

In the embodiment shown in FIG. 16, the normal mode choke L1 is magnetically shielded by a magnetic box 32 having an open lower surface, and this box 32 is connected to ground capacitors C3 and C4.
This is grounded to the AC terminal of the full-wave rectifier 15 on the inverter circuit 16 side.

As described above, the magnetic box 32 of ferrite or the like is attached near the normal mode choke L1, and this box 32 is grounded to the AC terminal of the full-wave rectifier 15, so that the normal mode choke L1 Box 32 for leakage magnetic flux
To the inverter circuit 16 side, which is a noise source, through the filter circuit 13 again.
It prevents the noise from returning to the side and suppresses the noise.

A discharge lamp lighting device according to another embodiment will be described with reference to FIGS.

The discharge lamp lighting device 11 shown in FIG. 17 is different from the discharge lamp lighting device 11 shown in FIG. 1 in that the common mode choke Tr1 of the circuit board 30 on which the common mode choke Tr1 is mounted as shown in FIG. , A metal plate 36, which is a metal body for electrostatic shielding, was attached, and this metal plate 36 was grounded from the grounding capacitors C3 and C4 to the DC input terminal on the negative electrode side of the full-wave rectifier 15 on the inverter circuit 16 side. Things.

As described above, the metal plate 36 is attached near the common mode choke Tr1, and this metal plate 36 is connected to the full-wave rectifier.
By grounding to the DC input terminal on the negative electrode side of 15, the leakage current from the common mode choke Tr1 is induced via the metal plate 36 to the inverter circuit 16 which is a noise source, passes through the filter circuit 13 again, and is directly The noise is prevented from returning to the commercial AC power supply e side as noise.

Another embodiment will be described with reference to FIG.

In the embodiment shown in FIG. 19, the common mode choke Tr1 is magnetically shielded by a magnetic box 37 having an open lower surface, and this box 37 is connected to ground capacitors C3 and C4.
This is grounded to the DC input terminal on the negative electrode side of the full-wave rectifier 15 which is the inverter circuit 16 side.

As described above, by mounting the magnetic box 37 of ferrite or the like in the vicinity of the common mode choke Tr1 and grounding the box 37 to the DC input terminal on the negative side of the full-wave rectifier 15, the common mode The leakage magnetic flux from the choke Tr1 is guided to the inverter circuit 16 which is a noise source through the box 37, passes again through the filter circuit 13, and is prevented from directly returning to the commercial AC power supply e as noise as it is. Suppress.

Further, a discharge lamp lighting device according to another embodiment will be described with reference to FIGS.

The discharge lamp lighting device 11 shown in FIG. 20 is different from the discharge lamp lighting device 11 shown in FIG. 1 in that, as shown in FIG. Attach a metal plate 41, which is a metal body for electrostatic shielding, and attach this metal plate 41 to the inverter circuit by grounding capacitors C3 and C4.
This is grounded to the AC output terminal of the full-wave rectifier 15 on the 16 side.

As described above, by attaching the metal plate 41 to the vicinity of the terminal 12 and grounding the metal plate 41 to the AC output terminal of the full-wave rectifier 15, the leakage current from the terminal 12 can be reduced.
To the inverter circuit 16 side, which is a noise source, through the filter circuit 13 again.
It prevents the noise from returning to the side and suppresses the noise.

Another embodiment will be described with reference to FIG.

In the embodiment shown in FIG. 22, the terminal 12 is magnetically shielded by a magnetic box 42 having an open lower surface.
This box 42 is connected to the grounding capacitors C3 and C4 to form an inverter circuit.
This is grounded to the AC output terminal of the full-wave rectifier 15 on the 16 side.

As described above, the box 42 made of a magnetic material such as ferrite is attached to the vicinity of the terminal 12, and the box 42 is grounded to the AC output terminal on the negative side of the full-wave rectifier 15. The leakage magnetic flux is guided to the inverter circuit 16 side, which is a noise source, through the box 42, and is again passed through the filter circuit 13,
This prevents the noise from directly returning to the commercial AC power supply e as it is and suppresses the noise.

[0050]

According to the filter circuit of the first aspect,
Since the winding start is connected to the load side of the normal mode choke connected between the power supply and the load, the stray capacitance can be reduced, and the noise returning to the power supply side can be suppressed.

According to the filter circuit of the second aspect, in addition to the filter circuit of the first aspect, the winding start side of the normal mode choke can be visually recognized, so that the winding start side can be reliably set on the load side.

According to the filter circuit of the third aspect, the noise generated by the choke is electrostatically shielded by the metal body and grounded on the load side, which is the noise source, from the grounding capacitor, so that the noise returning to the power supply side can be suppressed. .

According to the filter circuit of the fourth aspect, the noise generated by the choke is electrostatically shielded by the magnetic material and grounded on the load side, which is the noise source, from the grounding capacitor, so that the noise returning to the power supply side can be suppressed. .

According to the filter circuit of the fifth aspect, the noise generated at the terminal is electrostatically shielded by the metal body and grounded on the load side, which is the noise source, from the grounding capacitor, so that the noise returning to the power supply side can be suppressed. .

According to the filter circuit of the sixth aspect, the noise generated at the terminal is electrostatically shielded by the magnetic material and grounded on the load side, which is the noise source, from the grounding capacitor, so that the noise returning to the power supply side can be suppressed. .

According to the discharge lamp lighting device of the seventh aspect,
Since the filter circuit according to any one of claims 1 to 6 is connected between the power supply and the inverter circuit,
Each effect can be achieved.

According to the illuminating device of the eighth aspect, since there is provided the apparatus main body on which the discharge lamp to be lit by the discharge lamp lighting device of the seventh aspect is mounted, each effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of a discharge lamp lighting device of the present invention.

FIG. 2 is a perspective view showing an appearance of the lighting device.

FIG. 3 is a perspective view showing a normal mode choke of the above.

FIG. 4 is a bottom view of the same.

FIG. 5 is a simplified circuit diagram of the discharge lamp lighting device shown in FIG. 1;

FIG. 6 is an equivalent circuit diagram of the circuit shown in FIG. 5;

FIG. 7 is an explanatory diagram showing a normal mode choke in which the beginning of winding is connected to the commercial AC power supply side.

FIG. 8 is a circuit diagram showing a normal mode choke in which the beginning of the winding is connected to the commercial AC power supply side.

FIG. 9 is an explanatory diagram showing a normal mode choke in which the beginning of winding is connected to the inverter circuit side.

FIG. 10 is a circuit diagram showing a normal mode choke in which the beginning of the winding is connected to the inverter circuit side.

FIG. 11 is a perspective view showing a normal mode choke according to another embodiment of the present invention.

FIG. 12 is a perspective view showing a normal mode choke according to another embodiment of the present invention.

FIG. 13 is a perspective view showing a normal mode choke according to still another embodiment of the present invention.

FIG. 14 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 15 is a perspective view showing a state in which a metal plate is arranged near the normal mode choke in the above.

FIG. 16 is a perspective view showing a state in which a magnetic box is disposed in the normal mode choke.

FIG. 17 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 18 is a perspective view showing a state in which a metal plate is provided near the common mode choke in the same.

FIG. 19 is a perspective view showing a state where a magnetic box is provided in the common mode choke.

FIG. 20 is a circuit diagram showing a discharge lamp lighting device according to still another embodiment of the present invention.

FIG. 21 is a perspective view showing a state where a metal plate is arranged near the terminal.

FIG. 22 is a perspective view showing a state where a magnetic box is disposed on the terminal.

[Explanation of symbols]

 1 Appliance body 11 Discharge lamp lighting device 12 Terminal 13 Filter circuit 16 Inverter circuit as load 31, 36, 41 Metal plate as metal body 32, 37, 42 Box as magnetic material C3, C4 Grounding capacitor e Commercial AC power supply FL Fluorescent lamp as discharge lamp L1 Normal mode choke Tr1 Common mode choke

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Terasaka 4-3-1 Higashi-Shinagawa, Shinagawa-ku, Tokyo Inside Toshiba Lighting & Technology Corporation (72) Inventor Seiki Kosa 4-3-1 Higashi-Shinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation (72) Inventor Kazuyuki Uraya 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo F-term in Toshiba Lighting & Technology Corporation (Reference) 3K072 AA02 BA03 BB01 FA05 FA09 GB01 5J024 AA01 BA19 DA01 DA26 DA32 EA09

Claims (8)

[Claims] 1. A filter circuit comprising a normal mode choke connected between a power supply and a load and having a winding start connected to a load side. 2. The filter circuit according to claim 1, wherein the winding start side of the normal mode choke can be seen from the external appearance. 3. A grounding capacitor; a choke connected to the power supply side from the grounding capacitor; and a grounding capacitor disposed near the choke, shielding at least a part of the choke and grounding from the grounding portion of the grounding capacitor to the load side. A filtered metal body. 4. A grounding capacitor; a choke connected to the power supply side from the grounding capacitor; and a grounding capacitor disposed near the choke and shielding at least a part of the choke and grounding from the grounding portion of the grounding capacitor to the load side. A filtered magnetic material. 5. A terminal connected to the power supply side; a grounding capacitor; and a metal member disposed near the terminal and shielding at least a part of the terminal and grounded to the load side from the grounding portion of the grounding capacitor. A filter circuit comprising: 6. A terminal connected to the power supply side; a grounding capacitor; and a magnetic body disposed near the terminal and shielding at least a part of the terminal and grounded to the load side from the grounding portion of the grounding capacitor. A filter circuit comprising: 7. A discharge lamp comprising: an inverter circuit serving as a load for lighting a discharge lamp; and a power supply and the filter circuit according to claim 1 connected between the inverter circuit. Lighting device. 8. A lighting device comprising: the discharge lamp lighting device according to claim 7; and a fixture main body to which a discharge lamp to be lighted by the discharge lamp lighting device is mounted.