Lighting device, light source unit and lighting fixture

Abstract

To prevent remote control malfunctions and failures caused by common mode noise.SOLUTION: A lighting device 1 includes a converter circuit 11, a control circuit 60 that controls the switching of a switching element Q1 included in the converter circuit 11, a constant current circuit 61 that makes a load current If constant, a filter unit 13 that removes common mode noise, a printed circuit board that has the converter circuit 11, the control circuit 60, the constant current circuit 61, and the filter unit 13, and a case that accommodates the printed circuit board. The control circuit 60 is configured to control the switching of the switching element Q1 at a frequency higher or lower than the carrier frequency of one or more types of wireless signals using electromagnetic waves as a medium. The constant current circuit 61 makes the load current If match a target value specified by one or more types of wireless signals. The filter unit 13 is electrically connected to the case.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a lighting device, a light source unit, and a lighting fixture, and more specifically to a lighting device that blinks a light source in response to instructions via a wireless signal, a light source unit that includes the lighting device and the light source, and a lighting fixture that includes the light source unit and a fixture body. [Background technology]

[0002] As a conventional example, the lighting fixture described in Patent Document 1 is exemplified. The lighting fixture described in Patent Document 1 (hereinafter referred to as the conventional example) includes an LED module, a lighting device that controls the LED module to turn on, off, dim, etc., and a receiver that receives wireless signals from a remote control. The lighting device includes a DC power supply consisting of a boost chopper circuit for power factor correction, a buck converter circuit that steps down the output voltage of the DC power supply, and a control device that controls the boost chopper circuit and the buck converter circuit. The control device controls the buck converter circuit to turn the LED module on, off, dim, etc., in accordance with the wireless signal received by the receiver. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-98094 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional example, if the frequency of common mode noise flowing through the lighting device overlaps with the frequency of the wireless signal, there is a possibility that the remote control may malfunction or not function properly. Note that the frequency of common mode noise flowing through the lighting device often coincides with the switching frequency of the switching power supply circuit (boost chopper circuit and step-down chopper circuit).

[0005] An object of the present disclosure is to provide a lighting device, a light source unit, and a lighting fixture that can suppress malfunctions and non-operation of remote control due to common mode noise. [Means for solving the problem]

[0006] A lighting device according to one embodiment of the present disclosure includes a converter circuit that supplies a DC load current to a light source, a control circuit that controls the switching of a switching element included in the converter circuit, a constant current circuit that constants the load current, a filter unit that removes common-mode noise, a printed circuit board that includes the converter circuit, the control circuit, the constant current circuit, and the filter unit, and a case formed of a metal plate that houses the printed circuit board. The converter circuit includes a single-stage converter that can perform voltage conversion and power factor correction in parallel. The control circuit controls the switching of the switching element to perform voltage conversion and power factor correction in parallel, and is configured to control the switching of the switching element at a frequency higher or lower than the carrier frequency of one or more types of radio signals mediated by electromagnetic waves. The constant current circuit adjusts the load current to a target value specified by the one or more types of radio signals. The filter unit is electrically connected to the case.

[0007] A light source unit according to one aspect of the present invention includes the lighting device and a light source that is turned on by the lighting device.

[0008] A lighting fixture according to one aspect of the present invention includes the light source unit and a fixture body that supports the light source unit. [Effects of the Invention]

[0009] The lighting device, light source unit, and lighting fixture of the present disclosure have the advantage of being able to suppress malfunctions and non-operation of remote control due to common mode noise. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of a lighting fixture according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is an exploded perspective view of the light source unit and the lighting fixture according to the embodiment of the present disclosure. [Figure 3] FIG. 3 is a circuit diagram of a lighting device according to an embodiment of the present disclosure. [Figure 4] FIG. 4 is an exploded perspective view of a wireless device in the light source unit of the above embodiment. [Figure 5] FIG. 5 is a circuit diagram of the wireless device. [Figure 6] FIG. 6 is a partially omitted perspective view showing the mounting portion of the wireless device. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, lighting devices, light source units, and lighting fixtures according to embodiments of the present disclosure will be described in detail with reference to the drawings. However, each diagram described in the embodiments is a schematic diagram, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Note that the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0012] First, a lighting fixture 3 according to an embodiment of the present disclosure (hereinafter simply referred to as lighting fixture 3) will be described.

[0013] 1 and 2, the lighting fixture 3 includes a light source unit 2 according to an embodiment of the present disclosure (hereinafter abbreviated as light source unit 2) and a fixture body 4 that supports the light source unit 2. The light source unit 2 is detachably attached to the fixture body 4, which is directly attached to the ceiling. However, the fixture body 4 may be embedded in the ceiling, or may be directly attached to a wall or embedded in the wall.

[0014] The fixture main body 4 includes a rectangular box-shaped storage compartment 40 with an open bottom, a pair of reflectors 41 protruding obliquely upward from both longitudinal opening edges of the storage compartment 40, and a pair of end plates 42 provided at both longitudinal ends of the storage compartment 40 and the pair of reflectors 41 (see FIG. 2). The fixture main body 4 is installed on a ceiling by inserting suspension bolts (not shown) into at least two of a plurality of mounting holes 400 provided on the bottom surface of the storage compartment 40 and tightening nuts (not shown) onto the suspension bolts. A power supply line is inserted into one of a plurality of power supply holes 401 provided on the bottom surface of the storage compartment 40. The power supply line inserted into the power supply hole 401 is electrically connected to the lighting device 1 via a terminal block 402.

[0015] 2, the light source unit 2 includes a lighting device 1 according to an embodiment of the present disclosure (hereinafter abbreviated as lighting device 1) and an LED module 22 that is turned on by the lighting device 1. The light source unit 2 preferably includes an attachment member 21, a cover 23, and a wireless device 5. However, the light source unit 2 may include multiple LED modules 22.

[0016] The LED module 22 includes a large number of LEDs 220 and a substrate 221. The substrate 221 is formed in the shape of a long rectangular plate. The large number of LEDs 220 are mounted on the surface (lower surface) of the substrate 221 at the center in the short direction, and are aligned in a row at equal intervals along the longitudinal direction of the substrate 221.

[0017] The mounting member 21 is formed into a long, rectangular trough shape from a metal plate. The mounting member 21 has a long, rectangular bottom plate 210 and a pair of side plates 211 that rise upward from both ends of the bottom plate 210 in the longitudinal direction. The LED module 22 is attached to the underside of the bottom plate 210 by a plurality of claws cut and raised from the bottom plate 210.

[0018] Cover 23 is formed in a semi-cylindrical shape from a translucent synthetic resin such as acrylic resin or polycarbonate resin. Cover 23 also has a pair of protruding walls 233 that protrude upward along the longitudinal direction. Cover 23 houses mounting member 21 between the pair of protruding walls 233, and is attached to mounting member 21 by hooking hook portions formed on the tips (upper ends) of the pair of protruding walls 233 onto the tips (upper ends) of a pair of side plates 211 of mounting member 21.

[0019] The lighting device 1 has a printed circuit board 19 and a case 18 that houses the printed circuit board 19. The printed circuit board 19 is configured by mounting various electronic components, including integrated circuits, on a rectangular printed wiring board. The case 18 is formed from a metal plate in the shape of a long rectangular box with one surface (bottom) open. The case 18 houses the printed circuit board 19 and is fixed to a mounting member 21 with the open surface facing the upper surface of a bottom plate 210. Note that the case 18 is electrically connected to the mounting member 21 when fixed to the mounting member 21. Furthermore, the mounting member 21 is electrically connected to the fixture body 4 when the light source unit 2 is attached to the fixture body 4. Therefore, the case 18 of the lighting device 1 is electrically connected to the fixture body 4 through the mounting member 21.

[0020] 3 shows the circuit configuration of the lighting device 1. The lighting device 1 includes a filter unit 13, a rectifier circuit 10, a converter circuit 11, a control power supply circuit 12, a control device 6, and the like.

[0021] To remove both normal mode noise and common mode noise, the filter unit 13 preferably includes, for example, a Y capacitor (bypass capacitor), a common mode choke coil, and an X capacitor (bypass capacitor). The filter unit 13 is provided between an AC power source 9 such as a commercial power system and the rectifier circuit 10. The Y capacitor is electrically connected to the case 18 through the circuit ground.

[0022] The rectifier circuit 10 is made up of a diode bridge. The rectifier circuit 10 full-wave rectifies the AC voltage supplied from the AC power supply 9. A converter circuit 11 is electrically connected to a pair of pulsating current output terminals of the rectifier circuit 10. The pulsating current output terminal on the low potential side of the rectifier circuit 10 is electrically connected to ground.

[0023] The converter circuit 11 has a single-stage converter (also called a one-converter) that can perform voltage conversion and power factor correction in parallel. Specifically, the converter circuit 11 has a SEPIC (Single Ended Primary Inductance Converter) type DC / DC converter circuit.

[0024] The converter circuit 11 includes an input capacitor C1 that smoothes the pulsating voltage output from the rectifier circuit 10. The converter circuit 11 also includes a switching element Q1, a first inductor L1, a second inductor L2, a capacitor C2, a diode D1, a resistor R1, and an output capacitor C3. The first inductor L1 and the second inductor L2 may be wound around the same core or may be wound around separate cores. A first end of the first inductor L1 is electrically connected to a first end on the high potential side of the input capacitor C1. A second end of the first inductor L1 is electrically connected to a first end of the capacitor C2. A second end of the capacitor C2 is electrically connected to an anode of the diode D1 and a first end of the second inductor L2. A cathode of the diode D1 is electrically connected to a positive electrode of the output capacitor C3. A negative electrode of the output capacitor C3 and a second end of the second inductor L2 are electrically connected to a second end (ground) on the low potential side of the input capacitor C1. The switching element Q1 is an enhancement-type N-channel MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The drain of the switching element Q1 is electrically connected to the second end of the first inductor L1 and the first end of the capacitor C2. The source of the switching element Q1 is electrically connected to the second end on the low potential side of the input capacitor C1 via a resistor R1. The second end of the second inductor L2 and the negative electrode of the output capacitor C3 are electrically connected to the second end on the low potential side of the input capacitor C1. The positive electrode of the output capacitor C3 is electrically connected to the positive electrode of the LED module 22, and the negative electrode of the output capacitor C3 is electrically connected to the negative electrode of the LED module 22 via a resistor Rx for measuring the load current If.

[0025] As will be described later, the converter circuit 11 steps down the DC input voltage (for example, a DC voltage of 141 V) smoothed by the input capacitor C1 to a desired DC voltage (for example, a DC voltage of about 30 V to 60 V) by controlling the switching of the switching element Q1. The output voltage (desired DC voltage) of the converter circuit 11 is a DC voltage equal to or higher than the lighting start voltage of the LED module 22.

[0026] The control power supply circuit 12 includes an auxiliary winding L3, a resistor R2, a diode D2, and a capacitor C4. The auxiliary winding L3 is magnetically coupled to the second inductor L2 of the converter circuit 11. A first end of the auxiliary winding L3 is electrically connected to a first end of the resistor R2, and a second end of the auxiliary winding L3 is electrically connected to a second end on the low potential side of the input capacitor C1. A second end of the resistor R2 is electrically connected to an anode of the diode D2. A cathode of the diode D2 is electrically connected to a first end of the capacitor C4. A second end of the capacitor C4 is electrically connected to a second end on the low potential side of the input capacitor C1.

[0027] After the converter circuit 11 starts up, the control power supply circuit 12 rectifies and smoothes the voltage induced in the auxiliary winding L3 using a resistor R2, a diode D2, and a capacitor C4, and outputs a DC control power supply voltage Vcc from both ends of the capacitor C4. The control device 6 then operates on the control power supply voltage Vcc supplied from the control power supply circuit 12.

[0028] Next, we will explain the control device 6. The control device 6 includes a control circuit 60 that controls the switching of the switching element Q1 of the converter circuit 11, a constant current circuit 61 that keeps the load current If (the forward current flowing through the LED module 22) constant, and an overcurrent detection circuit. The control device 6 also includes a dimming control circuit 62, an error amplifier 63, a start-up circuit 64, and a start-up on / off circuit 65.

[0029] The control circuit 60 controls the switching of the switching element Q1 of the converter circuit 11 by applying a drive voltage Vg to the gate of the switching element Q1. The error amplifier 63 amplifies the difference between the negative electrode voltage of the LED module 22 and a reference voltage Vst, and outputs the amplified difference voltage (feedback voltage) to the control circuit 60. The control circuit 60 adjusts the duty ratio of the drive voltage Vg so that the feedback voltage input from the error amplifier 63 approaches zero. In other words, the control circuit 60 controls the switching of the switching element Q1 of the converter circuit 11 so as to output a constant voltage (a voltage equal to or higher than the lighting start voltage of the LED module 22) to the LED module 22.

[0030] The dimming control circuit 62 converts a PWM (Pulse Width Modulation) signal transmitted from the wireless device 5 via the signal cable 52, as described below, into a dimming signal and outputs the signal to the constant current circuit 61. The PWM signal is a voltage signal in which the dimming level is converted into a duty ratio. The dimming level corresponds to the current value of the load current If supplied by the lighting device 1 to the LED module 22. The dimming level is set to 100% when the current value of the load current If is equal to the current value of the rated current of the LED module 22. The dimming level and the duty ratio of the PWM signal have the following relationship: the dimming level is 100% when the duty ratio is 0 to 5%, and the dimming level is 5% (the lower limit) when the duty ratio is 98% or higher (excluding 100%). When the duty ratio is 5 to 98%, the dimming level decreases at a constant rate as the duty ratio increases. However, when the duty ratio is 100%, the dimming level is set to 0%, that is, the LED module 22 is turned off.

[0031] The dimming control circuit 62 outputs a dimming signal (DC voltage signal) with a maximum voltage value when the duty ratio of the PWM signal is 0 to 5%, and sets the voltage value of the dimming signal to zero when the duty ratio of the PWM signal is 100%.The dimming control circuit 62 outputs a dimming signal with a voltage value inversely proportional to the duty ratio when the duty ratio of the PWM signal is 5 to 98%.

[0032] The constant current circuit 61 includes an operational amplifier 610 , a voltage-current conversion circuit 611 , and a current mirror circuit 612 .

[0033] The operational amplifier 610, together with a feedback resistor (resistor R12) and an input resistor (resistor R11), constitutes a differential amplifier. The differential amplifier (operational amplifier 610) amplifies and outputs the voltage (differential voltage Vd) that is the difference between the dimming signal input from the dimming control circuit 62 and the voltage across the resistor Rx (a voltage proportional to the load current If).

[0034] The voltage-current conversion circuit 611 converts the differential voltage Vd output from the operational amplifier 610 into a current. The output current of the voltage-current conversion circuit 611 is proportional to the differential voltage Vd.

[0035] The current mirror circuit 612 is composed of two transistors TR1 and TR2. Each of the two transistors TR1 and TR2 is an enhancement-type N-channel MOSFET. However, each of the two transistors TR1 and TR2 may be a bipolar transistor. The drain of the transistor TR1 is electrically connected to the output terminal of the voltage-current conversion circuit 611 and the gates of the transistors TR1 and TR2. The drain of the transistor TR2 is electrically connected to the negative electrode of the LED module 22. The source of each of the transistors TR1 and TR2 is electrically connected to ground via a resistor Rx.

[0036] Thus, the current mirror circuit 612 operates to make the drain current of the transistor TR2, that is, the load current If flowing through the LED module 22, equal to the output current (target current) of the voltage-current conversion circuit 611.

[0037] As described above, the constant current circuit 61 operates to make the load current If flowing through the LED module 22 coincide with the target current corresponding to the dimming level indicated by the PWM signal. However, the constant current circuit 61 may have a transistor amplifier circuit instead of the current mirror circuit 612.

[0038] The starter circuit 64 generates the control power supply voltage Vcc in place of the control power supply circuit 12 from the time when the AC power supply 9 starts to supply AC voltage until the output voltage of the converter circuit 11 stabilizes.

[0039] The start-up on / off circuit 65 controls the on / off operation of the start-up circuit 64. The start-up on / off circuit 65 operates the start-up circuit 64 from the time when the AC power supply 9 starts to supply AC voltage until the output voltage of the converter circuit 11 stabilizes.

[0040] When AC power supply 9 starts supplying AC voltage, control device 6 preferably controls constant current circuit 61 so as to reduce load current If below the rated value during the operation period of start-up circuit 64. By controlling device 6 operating as described above, it is possible to prevent the output current of start-up circuit 64 and the output current (load current If) of constant current circuit 61 from simultaneously increasing to near their maximum values. However, control device 6 preferably operates in the same way even when the dimming level instructed by the PWM signal rises from 0% (a state in which LED module 22 is turned off) to any dimming level between several tens of percent and 100%.

[0041] The overcurrent detection circuit includes a comparator 66. The comparator 66 compares the voltage across the resistor R1, which is proportional to the source current of the switching element Q1, with a threshold voltage Vth. The comparator 66 outputs a low-level voltage when the voltage across the resistor R1 is less than the threshold voltage Vth, and outputs a high-level voltage when the voltage across the resistor R1 is equal to or greater than the threshold voltage Vth. When a high-level voltage is input from the comparator 66, the control circuit 60 stops the converter circuit 11 by halting the output of the drive voltage Vg. In other words, if an overcurrent flows through the switching element Q1 for some reason and is detected by the overcurrent detection circuit (comparator 66), the control device 6 stops the converter circuit 11, thereby protecting the lighting device 1 from the overcurrent. Note that the control circuit 60 preferably resumes output of the drive voltage Vg and operates the converter circuit 11 when the output voltage of the comparator 66 returns to a low level.

[0042] Furthermore, it is preferable that the constant current circuit 61 continues to operate to make the load current If constant even when a high-level voltage is output from the comparator 66. In other words, it is preferable that the lighting device 1 continues to operate the constant current circuit 61 to light the LED module 22 while a discharge current (load current If) is being supplied from the output capacitor C3 even after the converter circuit 11 has stopped.

[0043] 4, the wireless device 5 includes a circuit block 50, a housing 51, a signal cable 52, and a plug connector 53. The circuit block 50 includes a circuit board 50A and a circuit cover 50B.

[0044] As shown in FIG. 5, the circuit block 50 includes an antenna 500, a wireless communication circuit 501, a wireless control circuit 502, an infrared communication circuit 503, a photocoupler 504, resistors R51 and R52, and a signal output terminal 505. The circuit board 50A is divided into a first area 50AA and a second area (see FIG. 4). However, in FIG. 4, the second area of ​​the circuit board 50A is covered by a circuit cover 50B. The first area 50AA includes conductors constituting the antenna 500. The second area includes the wireless communication circuit 501, the wireless control circuit 502, the infrared communication circuit 503, the photocoupler 504, resistors R51 and R52, and the signal output terminal 505, excluding the antenna 500. The circuit cover 50B is formed in a box shape using a material that blocks electromagnetic waves, such as a metal plate such as a copper plate or an aluminum plate, and is attached to the circuit board 50A so as to cover the second area.

[0045] The wireless communication circuit 501 receives a wireless signal received by the antenna 500, for example, a wireless signal carried by radio waves in the 920 MHz band. The wireless communication circuit 501 then converts the received wireless signal (RF signal) into an intermediate frequency signal (IF signal) lower than the carrier frequency (920 MHz) and acquires a control command from the IF signal. The wireless signal is transmitted from a transmitter and transmits control commands for turning the light source unit 2 on and off and adjusting the dimming level. The wireless communication circuit 501 outputs the control command acquired from the wireless signal (IF signal) to the wireless control circuit 502. The wireless control circuit 502 is preferably configured, for example, by a microcontroller. The wireless control circuit 502 generates a control signal (PWM signal) for transmitting the control command (dimming level) received from the wireless communication circuit 501. The wireless control circuit 502 is electrically connected to a pair of signal lines through which the control signal is transmitted. The input terminal of a photocoupler 504 and a current-limiting resistor R51 are electrically connected in series to the wireless control circuit 502. That is, the control signal transmitted to the signal line is input to the input terminal of the photocoupler 504 via the wireless control circuit 502 .

[0046] The signal output terminal 505 is electrically connected to the control device 6 and the control power supply circuit 12 of the lighting device 1 via a signal cable 52 and a plug connector 53 (see FIG. 4). The signal cable 52 is composed of three electric wires 52A to 52C. The ground of the lighting device 1 is electrically connected to the negative output terminal of the photocoupler 504 (the emitter of the phototransistor) via one electric wire 52A. The connection point between the output terminal of the control power supply circuit 12 and one end of the resistor R52 is electrically connected via another electric wire 52B. The connection point between the other end of the resistor R52 and the positive output terminal of the photocoupler 504 (the collector of the phototransistor) is electrically connected to the dimming control circuit 62 of the control device 6 via the remaining electric wire 52C. In other words, a constant control power supply voltage Vcc is always applied to the series circuit of the resistor R52 and the phototransistor. Therefore, the control signal (PWM signal) input to the dimming control circuit 62 becomes low level when the input voltage to the photocoupler 504 is high level, and becomes high level when the input voltage to the photocoupler 504 is low level.

[0047] The infrared communication circuit 503 performs wireless communication using infrared rays. That is, the infrared communication circuit 503 receives (receives) an infrared signal with an infrared receiving element 503A mounted in the second region of the circuit board 50A, and outputs setting information and control information acquired from the received infrared signal to the wireless control circuit 502. The setting information is, for example, unique identification information assigned to a transmitter that is the sender of the wireless signal (radio wave). The control information is information including each command, such as a turn-on command to turn on the light source unit 2, a turn-off command to turn off the light source unit 2, and a dimming command to indicate the dimming level of the light source unit 2. The infrared signal complies with, for example, a standard defined by the Association for Electric Home Appliances (AHA), known as the AHA format. The AHA format uses infrared rays with a peak wavelength of 900 to 950 nm and a carrier wave consisting of a square wave with a duty ratio of 50% and a frequency of 33 kHz or more and 40 kHz or less.

[0048] The wireless control circuit 502 stores the setting information received from the infrared communication circuit 503 in a memory built into the microcontroller. The wireless communication circuit 501 acquires not only the control command but also the identification information of the transmitter that is the sender from the wireless signal received by the antenna 500, and outputs this to the wireless control circuit 502. If the identification information received from the wireless communication circuit 501 matches the identification information stored (registered) in the memory, the wireless control circuit 502 generates a control signal for transmitting the control command received from the wireless communication circuit 501. On the other hand, if the identification information received from the wireless communication circuit 501 does not match the identification information stored in the memory, the wireless control circuit 502 discards the control command received from the wireless communication circuit 501 and does not generate a control signal. In other words, even if the wireless communication circuit 501 can receive wireless signals from multiple transmitters, the wireless control circuit 502 only accepts control commands transmitted from a specific transmitter whose identification information has been registered in advance.

[0049] When wireless control circuit 502 receives control information from infrared communication circuit 503, it generates a control signal (PWM signal) for transmitting a command (turn on command, turn off command, dimming command) included in the received control information. When transmitting a turn on command, wireless control circuit 502 generates a PWM signal with a duty ratio of 95%. When transmitting a turn off command, wireless control circuit 502 generates a PWM signal with a duty ratio equal to or lower than a lower limit. When transmitting a dimming command, wireless control circuit 502 generates a PWM signal with a duty ratio corresponding to the dimming level specified in the dimming command.

[0050] As shown in Fig. 4, the housing 51 includes a body 510 and a cover 511. The body 510 is made of a box-shaped synthetic resin molded body with one side (bottom) open. The body 510 has two side walls facing each other in the short direction, and one of these side walls has an insertion groove 5100 through which the signal cable 52 is inserted. The body 510 also has two female threaded portions 5101. Furthermore, the body 510 has a pair of hook holes 5102 formed on two side walls facing each other in the long direction, each of which is aligned in the short direction.

[0051] The cover 511 has a rectangular plate-shaped lid body 5110, two pairs of fixed legs 5111, and an antenna housing section 5112. The fixed legs 5111 are formed so as to protrude upward from both ends of the lid body 5110 in the short direction. The two pairs of fixed legs 5111 have outward-protruding hooks 51110 at their tips (upper ends). The antenna housing section 5112 is formed in the shape of a flat rectangular box. The antenna housing section 5112 protrudes downward from the bottom surface of the lid body 5110 and is formed integrally with the lid body 5110 so as to open at the top surface of the lid body 5110. The antenna housing section 5112 has a through-hole 5113 formed at a longitudinal end thereof, which penetrates the lid body 5110 in the thickness direction (vertical direction).

[0052] The body 510 and the cover 511 are joined together by hooking two pairs of fixing legs 5111 of the cover 511 into four hook holes 5102 of the body 510. In the circuit block 50, the second region of the circuit board 50A to which the circuit cover 50B is attached is housed within the body 510, and the first region 50AA (antenna 500) of the circuit board 50A is housed in the antenna housing portion 5112. Note that the through-hole 5113 of the cover 511 faces the light receiving portion of the infrared light receiving element 503A mounted on the second region of the circuit board 50A. That is, an infrared signal transmitted from a setting device (wireless remote controller) (not shown) is received (received) by the infrared light receiving element 503A through the through-hole 5113 of the housing 51 (cover 511).

[0053] As shown in Fig. 6, the wireless device 5 is attached to the bottom plate 210 of the attachment member 21. A rectangular opening 213 is provided at one longitudinal end of the bottom plate 210 (the left end in Fig. 6) (see Figs. 2 and 6). The housing 51 of the wireless device 5 is fixed to the upper surface of the bottom plate 210 with the antenna housing 5112 passing through the opening 213 from the upper surface side to the lower surface side of the bottom plate 210. In other words, the wireless device 5 is attached to the attachment member 21 with the antenna housing 5112 protruding from the opening 213 to the lower surface side of the bottom plate 210 (see Fig. 6). The through-hole 5113 of the housing 51 is exposed to the lower surface side of the bottom plate 210 through the opening 213. Therefore, the infrared signal transmitted from the wireless remote controller passes through the translucent cover 23 and is received by the infrared receiving element 503A of the infrared communication circuit 503 through the through hole 5113 exposed from the opening 213 of the bottom plate 210.

[0054] Here, the smaller the difference between the frequency of the common-mode noise flowing from the converter circuit 11 to the case 18 through the filter unit 13 and the carrier frequency of each of the radio signal and the infrared signal, the greater the likelihood that the common-mode noise will interfere with the radio signal and the infrared signal. Regarding the radio signal, the smaller the difference between the frequency of the IF signal (e.g., 720 kHz) and the frequency of the common-mode noise, the greater the likelihood that the common-mode noise will interfere with the radio signal. If the common-mode noise interferes with the radio signal (IF signal) and the infrared signal, the radio device 5 (remote control by the radio device 5) is more likely to malfunction or become inoperable. The common-mode noise is mainly generated due to the switching operation of the switching element Q1 of the converter circuit 11. Therefore, the frequency of the common-mode noise matches the switching frequency of the switching element Q1.

[0055] Therefore, in the lighting device 1, the switching frequency of the switching element Q1 is fixed to a frequency lower than the carrier frequency of the wireless signal (the frequency of the IF signal) and higher than the carrier frequency of the infrared signal (e.g., 36.7 kHz). In other words, the control circuit 60 fixes the frequency of the drive voltage Vg applied to the gate of the switching element Q1 to, for example, 55 kHz. However, the frequency of the drive voltage Vg may be fixed to a frequency other than 55 kHz as long as it is lower than the frequency of the IF signal and higher than the carrier frequency of the infrared signal.

[0056] Therefore, since the lighting device 1 has a switching frequency of the switching element Q1 that is lower than the carrier frequency of the radio signal and higher than the carrier frequency of the infrared signal, it is possible to suppress malfunctions and non-operation of the remote control due to common mode noise.

[0057] Incidentally, when a boost chopper circuit and a buck converter circuit are included as in the conventional example described in Patent Document 1, the frequency of common-mode noise coincides with the switching frequency of the boost chopper circuit. Furthermore, since the switching frequency of the boost chopper circuit varies within a predetermined frequency range depending on fluctuations in the input voltage and the dimming level, the frequency of the common-mode noise also changes in accordance with the change in the switching frequency. Meanwhile, the cutoff frequency of the low-pass filter (filter for removing common-mode noise) in the filter unit 13 varies depending on the variations in the constants and temperature characteristics of the circuit elements that make up the low-pass filter. Therefore, if the switching frequency of the boost chopper circuit is lower than the cutoff frequency of the low-pass filter, it may become difficult for the filter unit 13 to remove common-mode noise.

[0058] In contrast, in lighting device 1, the switching frequency of switching element Q1 is fixed to a frequency (55 kHz) that is lower than the frequency of the IF signal and higher than the carrier frequency of the infrared signal. As a result, lighting device 1 can prevent malfunctions and non-operation of the remote control due to common mode noise even in situations where the cutoff frequency of filter unit 13 is prone to fluctuations.

[0059] As described above, the lighting device (1) according to the first aspect of the present disclosure includes a converter circuit (11) that supplies a DC load current (If) to a light source (LED module 22) that is a load. The lighting device (1) according to the first aspect also includes a control circuit (60) that controls the switching of a switching element (Q1) included in the converter circuit (11), and a constant current circuit (61) that makes the load current (If) constant. The converter circuit (11) has a single-stage converter that can perform voltage conversion and power factor correction in parallel. The control circuit (60) is configured to control the switching of the switching element (Q1) so as to perform voltage conversion and power factor correction in parallel. The control circuit (60) is configured to control the switching of the switching element (Q1) at a frequency higher or lower than the carrier frequency of one or more types of radio signals mediated by electromagnetic waves. The constant current circuit (61) causes the load current (If) to match a target value specified by the one or more types of radio signals.

[0060] In the lighting device (1) according to the first aspect, common mode noise that coincides with the switching frequency of the switching element (Q1) is less likely to overlap with the carrier frequency of the wireless signal, so that malfunctions and non-operation of the remote control due to common mode noise can be suppressed.

[0061] A lighting device (1) according to a second aspect of the present disclosure can be realized in combination with the first aspect. In the lighting device (1) according to the second aspect, the control circuit (60) is preferably configured to fix a switching frequency when controlling the switching of the switching element (Q1).

[0062] In the lighting device (1) according to the second aspect, common mode noise does not overlap with the carrier frequency of the wireless signal, so that malfunctions and non-operations of the remote control due to common mode noise can be further suppressed.

[0063] A lighting device (1) according to a third aspect of the present disclosure can be realized by combining it with the first or second aspect. In the lighting device (1) according to the third aspect, the one or more types of wireless signals preferably include a first wireless signal (infrared signal) transmitted via infrared rays. The control circuit (60) is preferably configured to control the switching of the switching element (Q1) at a frequency higher than the carrier frequency of the first wireless signal.

[0064] In the lighting device (1) according to the third aspect, the first wireless signal transmitted via infrared rays is less likely to interfere with common mode noise, thereby preventing malfunctions and non-operation of remote control using the first wireless signal.

[0065] A lighting device (1) according to a fourth aspect of the present disclosure can be realized by combining it with any of the first to third aspects. In the lighting device (1) according to the fourth aspect, it is preferable that the one or more types of wireless signals include a second wireless signal transmitted via radio waves. It is preferable that the control circuit (60) is configured to perform switching control of the switching element (Q1) at a frequency lower than the carrier frequency of the second wireless signal.

[0066] In the lighting device (1) according to the fourth aspect, the second wireless signal transmitted via radio waves is less likely to interfere with common mode noise, thereby preventing malfunctions and non-operation of remote control using the second wireless signal.

[0067] A light source unit (2) according to a fifth aspect of the present disclosure includes the lighting device (1) according to any one of the first to fourth aspects and a light source that is turned on by the lighting device (1).

[0068] The light source unit (2) according to the fifth aspect can suppress malfunctions and non-operations of the remote control due to common mode noise.

[0069] A light source unit (2) according to a sixth aspect of the present disclosure can be realized by combining it with the fifth aspect. The light source unit (2) according to the sixth aspect preferably includes a wireless device (5) that receives one or more types of wireless signals and generates a control signal for transmitting a target value indicated by the received wireless signals. The light source unit (2) according to the sixth aspect preferably includes a mounting member (21) to which the light source, the lighting device (1), and the wireless device (5) are attached. The mounting member (21) preferably has a bottom plate (210) formed in the shape of an elongated rectangular plate to which the lighting device (1) and the wireless device (5) are attached. The lighting device (1) and the wireless device (5) are preferably attached to the bottom plate (210) at positions spaced apart from each other along the longitudinal direction of the bottom plate (210).

[0070] In the light source unit (2) according to the sixth aspect, the wireless device (5) can be placed in a location where it is less likely to affect the light emitted from the light source.

[0071] A lighting fixture (3) according to a seventh aspect of the present disclosure includes the light source unit (2) according to the fifth or sixth aspect and a fixture body (4) that supports the light source unit (2).

[0072] The lighting fixture (3) according to the seventh aspect can suppress malfunctions and non-operation of the remote control due to common mode noise. [Explanation of symbols]

[0073] 1 lighting device 2 Light source unit 3. Lighting fixtures 4. Instrument body 5 Radio equipment 11 Converter circuit 13 Filter section 18 cases 19 Printed Circuit Board 21 Mounting material 22 LED module (light source) 60 Control circuit 61 Constant current circuit 210 Bottom plate Q1 switching element If load current

Claims

1. a converter circuit that supplies a DC load current to a light source that is a load; a control circuit that controls switching of a switching element included in the converter circuit; a constant current circuit that makes the load current a constant current; a filter section for removing common mode noise; a printed circuit board having the converter circuit, the control circuit, the constant current circuit, and the filter unit; a case formed of a metal plate and housing the printed circuit board; Equipped with the converter circuit has a single-stage converter capable of performing voltage conversion and power factor correction in parallel; the control circuit is configured to control the switching of the switching elements so as to perform voltage conversion and power factor correction in parallel, and to control the switching of the switching elements at a frequency higher or lower than a carrier frequency of one or more types of radio signals mediated by electromagnetic waves; the constant current circuit causes the load current to match a target value indicated by the one or more types of wireless signals; The filter unit is electrically connected to the case. Lighting device.

2. the one or more types of wireless signals include a first wireless signal using infrared light as a medium; the control circuit is configured to control switching of the switching element at a frequency higher than a carrier frequency of the first radio signal. The lighting device according to claim 1.

3. the one or more types of wireless signals include a second wireless signal carried by radio waves; the control circuit is configured to control the switching of the switching element at a frequency lower than a carrier frequency of the second radio signal.

3. The lighting device according to claim 1 or 2.

4. further comprising a rectifier circuit that rectifies an AC voltage supplied from an AC power supply and outputs the rectified AC voltage to the converter circuit; The filter unit is provided between the AC power supply and the rectifier circuit. The lighting device according to any one of claims 1 to 3.

5. A lighting device according to any one of claims 1 to 4; a light source that is turned on by the lighting device; Equipped with Light source unit.

6. The light source unit of claim 5; a fixture body that supports the light source unit; Equipped with Lighting fixtures.

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