JP2024032529A - Lighting devices and lighting equipment - Google Patents

Abstract

An object of the present disclosure is to reduce the influence of static electricity in a lighting device. A lighting device (1) includes a circuit section (2). The circuit section 2 includes a rectifier circuit 3, a power conversion circuit 4, an inductance element L1, and a bypass circuit 5. The rectifier circuit 3 rectifies the AC voltage supplied from the AC power source to generate a pulsating voltage. The power conversion circuit 4 converts the pulsating voltage generated by the rectifier circuit 3 into a DC voltage that is supplied to the light source 6 . Inductance element L1 is electrically connected between rectifier circuit 3 and power conversion circuit 4. Bypass circuit 5 bypasses the surge voltage generated in inductance element L1. [Selection diagram] Figure 1

Description

The present disclosure generally relates to a lighting device and a lighting fixture, and more particularly relates to a lighting device having a rectifier circuit and a lighting fixture including the lighting device.

The lighting device described in Patent Document 1 includes a pair of input ends, an input circuit, a power conversion circuit, and a pair of output ends. The pair of input ends are connected to a power source and receive power from the power source. The input circuit has a rectifying element. The input circuit is connected to the pair of input ends and transmits power from the pair of input ends to the power conversion circuit. An LED module is connected to the pair of output ends.

Japanese Patent Application Publication No. 2019-145395

However, in the lighting device described in Patent Document 1, when static electricity is applied, the voltage applied to the rectifier increases, and the rectifier may malfunction.

An object of the present disclosure is to provide a lighting device and a lighting fixture that reduce the influence of static electricity.

A lighting device according to one aspect of the present disclosure includes a circuit section. The circuit section includes a rectifier circuit, a power conversion circuit, an inductance element, and a bypass circuit. The rectifier circuit rectifies an AC voltage supplied from an AC power source to generate a pulsating voltage. The power conversion circuit converts the pulsating voltage generated by the rectifier circuit into a DC voltage that is supplied to a light source. The inductance element is electrically connected between the rectifier circuit and the power conversion circuit. The bypass circuit bypasses surge voltage generated in the inductance element.

A lighting fixture according to one aspect of the present disclosure includes the lighting device and an outer shell. The outer shell has a conductive part having the same potential as the housing. The outer shell accommodates the housing.

The present disclosure has the advantage that the effects of static electricity can be reduced.

FIG. 1 is a circuit block diagram of a lighting device according to a first embodiment. FIG. 2 is a perspective view of a lighting fixture including the above lighting device. FIG. 3 is a circuit block diagram of a lighting device according to a reference example. FIG. 4 is a circuit block diagram of a lighting device according to a second embodiment. FIG. 5 is a circuit block diagram of a lighting device according to Embodiment 3. FIG. 6 is a circuit block diagram of a lighting device according to Embodiment 4.

In each embodiment below, a lighting device and a lighting fixture of the present disclosure will be described using drawings. However, each embodiment described below is only a part of various embodiments of the present disclosure. Each of the embodiments described below can be modified in various ways depending on the design, etc., as long as the objective of the present disclosure can be achieved. Furthermore, each of the drawings described in each of the embodiments below is a schematic drawing, and the ratio of the size and thickness of each component in the drawing does not necessarily reflect the actual size ratio. do not have.

(Embodiment 1)
(1) Overview The lighting device 1 is a device that converts an alternating current voltage into a direct current voltage and supplies this direct current voltage to the light source 6. As shown in FIG. 1, the lighting device 1 of this embodiment includes a circuit section 2. As shown in FIG. The circuit section 2 includes a rectifier circuit 3, a power conversion circuit 4, an inductance element L1, and a bypass circuit 5. The rectifier circuit 3 rectifies the AC voltage supplied from the AC power source to generate a pulsating voltage. The power conversion circuit 4 converts the pulsating voltage generated by the rectifier circuit 3 into a DC voltage that is supplied to the light source 6 . Inductance element L1 is electrically connected between rectifier circuit 3 and power conversion circuit 4. Bypass circuit 5 bypasses the surge voltage generated in inductance element L1.

According to this embodiment, when static electricity is applied to the lighting device 1, the surge voltage caused by the static electricity can be bypassed by the bypass circuit 5. This reduces the surge voltage. Therefore, it is possible to reduce the possibility that the rectifier circuit 3 will malfunction due to the application of a surge voltage.

Further, by providing the inductance element L1, normal mode noise can be suppressed.

Since the inductance element L1 is provided after the rectifier circuit 3, the insulation distance required between the first end 101 and the second end 102 of the inductance element L1, and the winding of the inductance element L1 and the surrounding circuit are The required insulation distance between the Therefore, it becomes possible to downsize the lighting device 1. The peripheral circuits include, for example, the rectifier circuit 3, a varistor Z2 and a capacitor 42, which will be described later.

Furthermore, since the inductance element L1 is provided at the subsequent stage of the rectifier circuit 3, a pulsating current output from the rectifier circuit 3 instead of an alternating current flows through the inductance element L1. Therefore, compared to the case where an alternating current flows through the inductance element L1, the peak-to-peak of the current becomes smaller, and the hysteresis loss becomes smaller.

(2) Details of lighting device Hereinafter, the lighting device 1 of this embodiment will be explained in more detail. As shown in FIG. 1, the lighting device 1 includes a circuit section 2 and a housing 8. In this embodiment, the light source 6 will be described as not being a component of the lighting device 1; however, the light source 6 may be a component of the lighting device 1. That is, the lighting device 1 may include the light source 6.

Note that in FIG. 1, the stray capacitance FC1 generated between the circuit section 2 and the housing 8 is illustrated by a circuit symbol representing a capacitor. In FIG. 1, the positions where the circuit symbols corresponding to each stray capacitance FC1 are shown represent the positions where the stray capacitances FC1 occur, but the positions where the stray capacitances FC1 occur are not limited to the example in FIG. 1.

The housing 8 is made of metal, for example. The housing 8 has conductivity. The housing 8 houses the circuit section 2 . For example, the circuit section 2 is mounted on a board, and the housing 8 houses the board and the circuit section 2. Note that the light source 6 may be housed in the housing 8 or may be placed outside the housing 8.

The circuit section 2 includes at least a rectifier circuit 3, a power conversion circuit 4, an inductance element L1, and a bypass circuit 5. Further, in this embodiment, as shown in FIG. 1, the circuit section 2 further includes a fuse F1, a varistor Z1, a capacitor C1, a low-pass filter circuit LF1, and a varistor Z2. The low-pass filter circuit LF1 includes, for example, two inductance elements L11 and L12. The low-pass filter circuit LF1 is, for example, a common mode line filter that includes two inductance elements L11 and L12 that are magnetically coupled to each other.

Further, the circuit section 2 further includes two input ends 21 and 22 and two output ends 23 and 24. The input ends 21 and 22 and the output ends 23 and 24 may each be a terminal to which an electric wire is connected, or may be a part of a conductor (wiring) constituting the circuit section 2.

Input terminals 21 and 22 are electrically connected to an AC power source. Further, the input end 21 is on the non-grounded side, and the input end 22 is on the grounded side.

A first end of the fuse F1 is electrically connected to the input end 21. A second end of fuse F1 is electrically connected to a first end of inductance element L11. The second end of the inductance element L11 is electrically connected to the first input terminal 31 of the rectifier circuit 3.

A first end of an inductance element L12 is electrically connected to the input end 22. The second end of the inductance element L12 is electrically connected to the second input terminal 32 of the rectifier circuit 3.

Varistor Z1 is used as a surge absorber. Capacitor C1 is a filter capacitor. A first end of the varistor Z1 and a first end of the capacitor C1 are electrically connected to a conductor that electrically connects the second end of the fuse F1 and the first end of the inductance element L11. The second end of the varistor Z1 and the second end of the capacitor C1 are electrically connected to a conductor that electrically connects the input end 22 and the first end of the inductance element L12.

The rectifier circuit 3 is a diode bridge including four diodes D1 to D4. The anode of the diode D1 is electrically connected to the first input terminal 31 of the rectifier circuit 3. A cathode of the diode D1 is electrically connected to a positive terminal 33 (first output terminal) of the rectifier circuit 3.

The anode of the diode D2 is electrically connected to the second input terminal 32 of the rectifier circuit 3. The cathode of the diode D2 is electrically connected to the positive terminal 33 of the rectifier circuit 3.

The anode of the diode D3 is electrically connected to the negative terminal 34 (second output terminal) of the rectifier circuit 3. A cathode of the diode D3 is electrically connected to the first input terminal 31 of the rectifier circuit 3.

The anode of the diode D4 is electrically connected to the negative terminal 34 of the rectifier circuit 3. A cathode of the diode D4 is electrically connected to the second input terminal 32 of the rectifier circuit 3.

The rectifier circuit 3 outputs a pulsating voltage. The positive terminal 33 is a terminal that has a higher potential than the negative terminal 34.

In this way, the rectifier circuit 3 is a diode bridge that performs full-wave rectification of the alternating current voltage. The rectifier circuit 3 has a positive terminal 33 and a negative terminal 34, and the pulsating voltage output by the rectifier circuit 3 is a voltage between the positive terminal 33 and the negative terminal 34.

A parallel circuit including an inductance element L1 and a bypass circuit 5 (resistor R1) is provided downstream of the rectifier circuit 3. That is, the bypass circuit 5 is connected in parallel with the inductance element L1. Moreover, the bypass circuit 5 includes a resistor R1. The bypass circuit 5 of this embodiment consists only of the resistor R1.

A first end 101 of the inductance element L1 is electrically connected to a first end of the bypass circuit 5. The second end 102 of the inductance element L1 is electrically connected to the second end of the bypass circuit 5.

Further, the first end 101 of the inductance element L1 is electrically connected to the positive terminal 33 of the rectifier circuit 3. The second end 102 of the inductance element L1 is electrically connected to a positive input terminal 411 of a voltage conversion circuit 41 (described later). The negative terminal 34 of the rectifier circuit 3 is electrically connected to the negative input terminal 412 of the voltage conversion circuit 41.

A first end of the varistor Z2 and a first end of the capacitor 42 (described later) are electrically connected to a conductor that electrically connects the second end 102 of the inductance element L1 and the positive input terminal 411. There is. The second end of the varistor Z2 and the second end of the capacitor 42 are electrically connected to a conductor that electrically connects the negative terminal 34 of the rectifier circuit 3 and the negative input terminal 412.

The power conversion circuit 4 converts the pulsating voltage supplied from the rectifier circuit 3 into a DC voltage. The power conversion circuit 4 includes a voltage conversion circuit 41 and a capacitor 42. The capacitor 42 smoothes the pulsating voltage supplied from the rectifier circuit 3 and converts it into a DC voltage. The voltage conversion circuit 41 is provided after the capacitor 42. The voltage conversion circuit 41 converts the input DC voltage into a DC voltage of a predetermined magnitude. The voltage conversion circuit 41 is, for example, a linear regulator or a switching regulator.

The voltage conversion circuit 41 outputs a DC voltage to the output terminals 23 and 24. A DC voltage output from the voltage conversion circuit 41 is applied to the light source 6 via the output ends 23 and 24. This turns on the light source 6.

The light source 6 includes, for example, one or more light emitting diode elements, organic electroluminescent elements or laser diode elements.

(3) Lighting Fixture Next, the lighting fixture 9 will be explained with reference to FIG. 2.

The lighting fixture 9 includes a lighting device 1 (see FIG. 1) and an outer shell 90. The outer shell 90 has a conductive portion 91 . The conductive part 91 has conductivity. The potential of the conductive portion 91 is the same as that of the casing 8 (see FIG. 1). The outer shell 90 accommodates the housing 8.

The conductive portion 91 is made of metal, for example. The conductive part 91 is formed in a box shape with an opening on one surface.

As shown in FIG. 2, the outer shell 90 includes a cover 92 in addition to the conductive part 91. The cover 92 covers the opening of the conductive part 91. The cover 92 has translucency. The cover 92 is made of, for example, synthetic resin.

The lighting device 1 and the light source 6 are housed in the conductive part 91. The light emitted from the light source 6 is emitted through the cover 92.

The conductive part 91 is grounded. Furthermore, the conductive portion 91 is electrically connected to the housing 8 . That is, the casing 8 is grounded via the conductive part 91.

In this embodiment, the light source 6 will be described as not being a component of the lighting fixture 9; however, the light source 6 may be a component of the lighting fixture 9. That is, the lighting fixture 9 may include the light source 6.

(4) Comparison with reference example FIG. 3 illustrates a lighting device 1P according to a reference example.

The lighting device 1P differs from the lighting device 1 of the first embodiment in that it does not include the bypass circuit 5.

In the lighting devices 1 and 1P, when static electricity is applied to the housing 8, there is a possibility that the inductance element L1 and the stray capacitance FC1 resonate, and a high voltage is applied to the inductance element L1. As a result, a high voltage corresponding to the voltage of the inductance element L1 may be applied to the diodes D1 to D4 of the rectifier circuit 3.

Further, there is a possibility that a voltage even higher than the voltage corresponding to the voltage of the inductance element L1 may be applied to the diodes D1 to D4 of the rectifier circuit 3. More specifically, when static electricity is applied to the housing 8, there is a possibility that the inductance element L11 or L12 and the stray capacitance FC1 resonate, and a high voltage is applied to the inductance element L11 or L12. As a result, a high voltage corresponding to the differential voltage between the voltage of the inductance element L1 and the voltage of the inductance element L11 or L12 may be applied to the diodes D1 to D4 of the rectifier circuit 3.

Each of the diodes D1 to D4 may fail if a high voltage is applied thereto. Therefore, as shown in FIG. 3 of the reference example, a series circuit of two capacitors C3 is provided in the lighting device 1P, the first end of the series circuit is electrically connected to the negative terminal 34 of the rectifier circuit 3, and the second end It is possible to reduce the voltage applied to the diodes D1 to D4 by grounding the diodes D1 to D4. Note that in FIG. 3, the second end of the series circuit is electrically connected to the casing 8 and thereby grounded.

On the other hand, the lighting device 1 of Embodiment 1 is electrically connected between the housing 8 and the negative electrode side electric path between the rectifier circuit 3 and the power conversion circuit 4 (one or more ) is not equipped with capacitor C3. The capacitor C3 mentioned here is a capacitor as an electronic component, and the stray capacitance FC1 does not correspond to the capacitor C3.

In the lighting device 1 of the first embodiment, the voltage applied to the diodes D1 to D4 is relaxed by the bypass circuit 5.

Furthermore, in the reference example, instead of the series circuit of the two capacitors C3, a varistor may be provided at the same position as the series circuit, thereby making it possible to reduce the voltage applied to the diodes D1 to D4. In the lighting device 1 of the first embodiment, the voltage applied to the diodes D1 to D4 can be relaxed without providing a varistor. That is, the lighting device 1 of the first embodiment does not include a varistor electrically connected between the housing 8 and the negative electrode side electric path between the rectifier circuit 3 and the power conversion circuit 4.

Furthermore, in the reference example, the voltage applied to the diodes D1 to D4 can be alleviated not only by a series circuit of two capacitors C3 or a varistor, but also by providing a surge absorber having a similar function. The series circuit of two capacitors C3 and the varistor are each an example of a surge absorber. In the lighting device 1 of the first embodiment, the voltage applied to the diodes D1 to D4 can be relaxed without providing a surge absorber. That is, the lighting device 1 of the first embodiment does not include a surge absorber electrically connected between the housing 8 and the negative electrode side electric path between the rectifier circuit 3 and the power conversion circuit 4.

In the lighting device 1 of the first embodiment, the negative electrode side electrical path between the rectifier circuit 3 and the power conversion circuit 4 is a conductor that electrically connects the negative electrode terminal 34 and the negative electrode side input terminal 412 of the power conversion circuit 4. It is. Even if the lighting device 1 is not provided with a surge absorber in such a location, by providing the bypass circuit 5, the voltage applied to the diodes D1 to D4 can be relaxed. Examples of the surge absorber mentioned here are a gap arrester, a gas arrester, a Zener diode, and a varistor.

(5) Modification Examples Modification examples of Embodiment 1 will be listed below. The following modified examples may be realized in combination as appropriate. Further, the following modified examples may be applied to Embodiments 2 to 4 as appropriate.

Although the rectifier circuit 3 of the first embodiment is a diode bridge that performs full-wave rectification of AC voltage, the rectifier circuit 3 may be a circuit that performs half-wave rectification of AC voltage.

Varistors Z1 and Z2 are examples of surge absorbers. For example, a surge absorber such as a Zener diode may be used instead of the varistors Z1 and Z2.

At least one of the varistors Z1 and Z2, the capacitor C1, and the low-pass filter circuit LF1 may be omitted.

As shown in the reference example (see FIG. 3), the lighting device 1 is electrically connected between the housing 8 and the negative electrode side electrical path between the rectifier circuit 3 and the power conversion circuit 4. , one or more capacitors C3, or a surge absorber other than the capacitor C3. The number of capacitors C3 may be one, or may be two or more in order to prevent electrical connection between the circuit section 2 and the casing 8 when one capacitor C3 fails. good. Further, common mode noise is effectively suppressed by configuring an LC filter with one or more capacitors C3 and the inductance of the low-pass filter circuit LF1. In particular, when a switching regulator is used in the voltage conversion circuit 41, there is a concern that noise generated by switching may leak into the commercial power supply system, causing interference with other devices connected to the commercial power supply system. Therefore, it is necessary to suppress the noise that flows out.

(Embodiment 2)
Hereinafter, a lighting device 1A according to Embodiment 2 will be described using FIG. 4. Components similar to those in Embodiment 1 are designated by the same reference numerals and description thereof will be omitted.

In this embodiment, the configuration of the bypass circuit 5 is different from that in the first embodiment. The bypass circuit 5 of this embodiment includes a resistor R1 and a capacitor C4. Capacitor C4 is connected in series with resistor R1. A series circuit of resistor R1 and capacitor C4 is connected in parallel to inductance element L1.

In this embodiment, as in the first embodiment, the surge voltage caused by static electricity can be bypassed by the bypass circuit 5. Further, by providing the capacitor C4, the direct current component and low frequency component of the current are suppressed from flowing into the bypass circuit 5. This suppresses noise in the low frequency band.

As a modification of the second embodiment, the bypass circuit 5 may be configured to include at least a capacitor C4. For example, the bypass circuit 5 may be composed only of the capacitor C4. In this case as well, the noise in the low frequency band is suppressed by the capacitor C4, and the surge voltage due to static electricity can be bypassed by the bypass circuit 5.

(Embodiment 3)
Hereinafter, a lighting device 1B according to Embodiment 3 will be described using FIG. 5. Components similar to those in Embodiment 1 are designated by the same reference numerals and description thereof will be omitted.

In this embodiment, the configuration of the bypass circuit 5 is different from that in the first embodiment. The bypass circuit 5 of this embodiment includes a nonlinear resistance element 50 instead of the resistor R1. The bypass circuit 5 of this embodiment consists only of the nonlinear resistance element 50. Nonlinear resistance element 50 is connected in parallel to inductance element L1.

The nonlinear resistance element 50 has a characteristic that its impedance decreases as the applied voltage increases. Examples of the nonlinear resistance element 50 of the bypass circuit 5 are a Zener diode such as a TVS diode, and a varistor.

Since the bypass circuit 5 includes the nonlinear resistance element 50, the surge voltage caused by static electricity can be bypassed by the bypass circuit 5. Further, noise is suppressed by the nonlinear resistance element 50. Noise can be further suppressed by selecting a nonlinear resistance element 50 that has a relatively small capacitance between terminals.

(Embodiment 4)
Hereinafter, a lighting device 1C according to Embodiment 4 will be described using FIG. 6. Components similar to those in Embodiment 1 are designated by the same reference numerals and description thereof will be omitted.

This embodiment is different from the first embodiment in the configuration and arrangement of the bypass circuit 5. The bypass circuit 5 of this embodiment includes a capacitor C5. The capacitor C5 is electrically connected between the positive terminal 33 and the negative terminal 34 before the inductance element L1. More specifically, the first end of the capacitor C5 is electrically connected to a conductor that electrically connects the positive terminal 33 and the first end of the inductance element L1. The second end of the capacitor C5 is electrically connected to a conductor that electrically connects the negative terminal 34 and the negative input terminal 412 of the voltage conversion circuit 41.

Also in the configuration of this embodiment, the surge voltage due to static electricity can be bypassed by the bypass circuit 5, and the surge voltage can be reduced.

(summary)
The following aspects are disclosed from the embodiments described above.

The lighting device (1, 1A to 1C) according to the first aspect includes a circuit section (2). The circuit section (2) includes a rectifier circuit (3), a power conversion circuit (4), an inductance element (L1), and a bypass circuit (5). The rectifier circuit (3) rectifies the AC voltage supplied from the AC power source to generate a pulsating voltage. The power conversion circuit (4) converts the pulsating voltage generated by the rectifier circuit (3) into a DC voltage that is supplied to the light source (6). The inductance element (L1) is electrically connected between the rectifier circuit (3) and the power conversion circuit (4). The bypass circuit (5) bypasses the surge voltage generated in the inductance element (L1).

According to the above configuration, when static electricity is applied to the lighting device (1, 1A to 1C), the surge voltage due to the static electricity can be bypassed by the bypass circuit (5). That is, the influence of static electricity on the lighting devices (1, 1A to 1C) can be reduced.

Further, the lighting device (1, 1A to 1C) according to the second aspect further includes a housing (8) in the first aspect. The housing (8) has conductivity. The housing (8) houses the circuit section (2).

According to the above configuration, noise can be suppressed in the lighting devices (1, 1A to 1C).

Further, in the lighting device (1, 1A to 1C) according to the third aspect, in the second aspect, the negative electrode side between the housing (8), the rectifier circuit (3), and the power conversion circuit (4) It does not include a surge absorber that is electrically connected between the electrical circuit and the electrical circuit.

According to the above configuration, the number of parts of the lighting device (1, 1A to 1C) can be reduced.

Further, in the lighting device (1, 1A to 1C) according to the fourth aspect, in the second or third aspect, the connection between the housing (8), the rectifier circuit (3), and the power conversion circuit (4) is It does not include a capacitor (C3) electrically connected between it and the negative electrode side electrical path.

According to the above configuration, the number of parts of the lighting device (1, 1A to 1C) can be reduced.

Further, in the lighting device (1, 1A to 1C) according to the fifth aspect, in any one of the second to fourth aspects, the lighting device (1, 1A to 1C) includes a housing (8), a rectifier circuit (3), and a power conversion circuit (4). ) and a varistor electrically connected between the negative electrode side electrical path and the

According to the above configuration, the number of parts of the lighting device (1, 1A to 1C) can be reduced.

Further, in the lighting device (1, 1A, 1B) according to the sixth aspect, in any one of the first to fifth aspects, the bypass circuit (5) is connected in parallel with the inductance element (L1). There is.

According to the above configuration, surge voltage due to static electricity can be suppressed.

Furthermore, in the lighting device (1, 1A) according to the seventh aspect, in the sixth aspect, the bypass circuit (5) includes a resistor (R1).

According to the above configuration, the surge voltage can be lowered by the resistor (R1).

Furthermore, in the lighting device (1A) according to the eighth aspect, in the seventh aspect, the bypass circuit (5) further includes a capacitor (C4) connected in series to the resistor (R1).

According to the above configuration, noise in the low frequency band is suppressed.

Further, in the lighting device (1B) according to the ninth aspect, in any one of the sixth to eighth aspects, the bypass circuit (5) includes a nonlinear resistance element (50). The nonlinear resistance element (50) has a characteristic that impedance decreases as the applied voltage increases.

According to the above configuration, noise is suppressed.

Further, in the lighting device (1C) according to the tenth aspect, in any one of the first to ninth aspects, the rectifier circuit (3) is a diode bridge that performs full-wave rectification of the AC voltage. The rectifier circuit (3) has a positive terminal (33) and a negative terminal (34). The pulsating voltage is the voltage between the positive terminal (33) and the negative terminal (34). The bypass circuit (5) includes a capacitor (C5) electrically connected between a positive terminal (33) and a negative terminal (34) at a stage before the inductance element (L1).

According to the above configuration, surge voltage due to static electricity can be suppressed.

The configurations other than the first aspect are not essential to the lighting device (1, 1A to 1C) and can be omitted as appropriate.

Further, the lighting fixture (9) according to the eleventh aspect includes the lighting device (1, 1A to 1C) according to any one of the first to tenth aspects, and an outer shell (90). The lighting device (1, 1A to 1C) includes a housing (8). The housing (8) has electrical conductivity and houses the circuit section (2). The outer shell (90) has a conductive part (91) at the same potential as the housing (8). The shell (90) houses the housing (8).

According to the above configuration, noise can be suppressed in the lighting devices (1, 1A to 1C).

1, 1A to 1C Lighting device 2 Circuit section 3 Rectifier circuit 4 Power conversion circuit 5 Bypass circuit 6 Light source 8 Housing 9 Lighting fixture 33 Positive terminal 34 Negative terminal 50 Nonlinear resistance element 90 Outer shell 91 Conductive section C3 Capacitor C4 Capacitor C5 Capacitor L1 Inductance element R1 resistor

Claims (11)

a rectifier circuit that rectifies AC voltage supplied from an AC power source to generate pulsating voltage;
a power conversion circuit that converts the pulsating voltage generated by the rectifier circuit into a DC voltage that is supplied to a light source;
an inductance element electrically connected between the rectifier circuit and the power conversion circuit;
a circuit section having a bypass circuit that bypasses a surge voltage generated in the inductance element;
lighting device. further comprising a casing having conductivity and accommodating the circuit section;
The lighting device according to claim 1. does not include a surge absorber electrically connected between the casing and the negative electrode side electrical path between the rectifier circuit and the power conversion circuit;
The lighting device according to claim 2. does not include a capacitor electrically connected between the housing and the negative electrode side electrical path between the rectifier circuit and the power conversion circuit;
The lighting device according to claim 2. does not include a varistor electrically connected between the housing and the negative electrode side electrical path between the rectifier circuit and the power conversion circuit;
The lighting device according to claim 2. the bypass circuit is connected in parallel with the inductance element,
The lighting device according to claim 1. The bypass circuit includes a resistor.
The lighting device according to claim 6. The bypass circuit further includes a capacitor connected in series with the resistor.
The lighting device according to claim 7. The bypass circuit includes a nonlinear resistance element having a characteristic that impedance decreases as the applied voltage increases.
The lighting device according to claim 6. The rectifier circuit is a diode bridge that full-wave rectifies the AC voltage,
The rectifier circuit has a positive terminal and a negative terminal, and the pulsating voltage is a voltage between the positive terminal and the negative terminal,
The bypass circuit includes a capacitor electrically connected between the positive terminal and the negative terminal at a stage before the inductance element.
The lighting device according to claim 1. A lighting device according to claim 2;
an outer shell having a conductive part having the same potential as the casing and accommodating the casing;
lighting equipment.

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