JP7515079B2 - Light source unit and lighting fixture - Google Patents

Description

The present disclosure relates to 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 wireless signals, a light source unit including the light source, and a lighting fixture that includes the light source unit and a fixture body.

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) comprises 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 comprises a DC power supply consisting of a boost chopper circuit for power factor improvement, 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 on, off, dim, etc. the LED module in response to the wireless signal received by the receiver.

JP 2017-98094 A

However, in conventional examples, 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. Furthermore, 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).

An object of the present disclosure is to provide a light source unit and a lighting device that can suppress malfunctions and non-operation of remote control caused by common mode noise.

A light source unit according to an embodiment of the present disclosure includes a lighting device, a light source that is turned on by the lighting device, a wireless device that receives a radio signal mediated by radio waves by an antenna and generates a control signal for transmitting a target value indicated by the received wireless signal, and a mounting member to which the light source, the lighting device, and the wireless device are attached. The lighting device includes a converter circuit that supplies a DC load current to the light source, a control circuit that controls switching of a switching element included in the converter circuit, and a constant current circuit that makes the load current a constant current. The converter circuit has a single-stage converter that can perform voltage conversion and power factor correction in parallel. The control circuit is configured to control the switching of the switching element so as to perform voltage conversion and power factor correction in parallel, and to control the switching of the switching element at a frequency lower than the carrier frequency of the wireless signal. The constant current circuit makes the load current coincide with the target value indicated by the wireless signal. The control circuit is configured to fix a switching frequency when controlling the switching of the switching element. The mounting member has a bottom plate formed in a long rectangular plate shape to which the lighting device and the wireless device are attached. The lighting device is attached to the bottom plate at a position separated from the wireless device along the longitudinal direction of the bottom plate. The wireless device has a circuit board and the antenna made of a conductor formed on a surface of the circuit board, and is attached to one end of the bottom plate in the longitudinal direction.

A lighting fixture according to one aspect of the present invention comprises the light source unit and a fixture body that supports the light source unit.

The 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 caused by common mode noise.

FIG. 1 is a perspective view of a lighting fixture according to an embodiment of the present disclosure. FIG. 2 is an exploded perspective view of the light source unit and the lighting fixture according to the embodiment of the present disclosure. FIG. 3 is a circuit diagram of a lighting device according to an embodiment of the present disclosure. FIG. 4 is an exploded perspective view of a wireless device in the light source unit. FIG. 5 is a circuit diagram of the wireless device. FIG. 6 is a perspective view, with some parts omitted, showing the mounting portion of the wireless device of the above.

The lighting device, light source unit, and lighting fixture according to the embodiments of the present disclosure will be described in detail below with reference to the drawings. However, each figure described in the embodiments is a schematic diagram, and the ratio of the size and thickness of each component does not necessarily reflect the actual dimensional ratio. Note that the configuration described in the following embodiment is merely one example of the present disclosure. The present disclosure is not limited to the following embodiment, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

First, we will explain the lighting fixture 3 (hereinafter, abbreviated as lighting fixture 3) according to an embodiment of the present disclosure.

As shown in Figs. 1 and 2, the lighting fixture 3 has 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 that 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.

The fixture body 4 includes a rectangular box-shaped storage section 40 with an open bottom, a pair of reflectors 41 protruding obliquely upward from the opening edges on both sides along the longitudinal direction of the storage section 40, and a pair of end plates 42 provided at both ends in the longitudinal direction of the storage section 40 and the pair of reflectors 41 (see FIG. 2). The fixture body 4 is installed on the ceiling by inserting a hanging bolt (not shown) into at least two of the multiple mounting holes 400 provided on the bottom surface of the storage section 40 and tightening nuts (not shown) on the hanging bolts. In addition, a power line is inserted into one of the multiple power supply holes 401 provided on the bottom surface of the storage section 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.

As shown in FIG. 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.

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 in a line at equal intervals along the longitudinal direction of the substrate 221, at the center of the short side of the surface (lower surface) of the substrate 221.

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

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

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 of a metal plate in the shape of a long rectangular box with one side (bottom side) open. The case 18 houses the printed circuit board 19 and is fixed to the mounting member 21 so that the open side faces the upper surface of the 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.

The circuit configuration of the lighting device 1 is shown in FIG. 3. The lighting device 1 includes a filter section 13, a rectifier circuit 10, a converter circuit 11, a control power supply circuit 12, a control device 6, etc.

The filter unit 13 preferably includes, for example, a Y capacitor (bypass capacitor), a common mode choke coil, and an X capacitor (bypass capacitor) in order to remove both normal mode noise and common mode noise. 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.

The rectifier circuit 10 is composed of a diode bridge. The rectifier circuit 10 full-wave rectifies the AC voltage supplied from the AC power source 9. The 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.

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.

The converter circuit 11 includes an input capacitor C1 that smoothes the pulsating voltage output from the rectifier circuit 10. The converter circuit 11 further 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. However, the first inductor L1 and the second inductor L2 may be wound around the same iron core, or may be wound around different iron cores. The first end of the first inductor L1 is electrically connected to the first end of the high potential side of the input capacitor C1. The second end of the first inductor L1 is electrically connected to the first end of the capacitor C2. The second end of the capacitor C2 is electrically connected to the anode of the diode D1 and the first end of the second inductor L2. The cathode of the diode D1 is electrically connected to the positive electrode of the output capacitor C3. The negative electrode of the output capacitor C3 and the second end of the second inductor L2 are electrically connected to the second end (ground) of 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 of 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 of 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.

The converter circuit 11 reduces the DC input voltage (e.g., a DC voltage of 141 V) smoothed by the input capacitor C1 to a desired DC voltage (e.g., a DC voltage of about 30 V to 60 V) by controlling the switching of the switching element Q1 as described below. 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.

The control power supply circuit 12 has 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.

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 resistor R2, diode D2, and capacitor C4, and outputs a DC control power supply voltage Vcc from both ends of capacitor C4. The control device 6 then operates using the control power supply voltage Vcc supplied from the control power supply circuit 12.

Next, the control device 6 will be described. 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 further includes a dimming control circuit 62, an error amplifier 63, a start-up circuit 64, and a start-up on/off circuit 65.

The control circuit 60 applies a drive voltage Vg to the gate of the switching element Q1 of the converter circuit 11 to control the switching of the switching element Q1. The error amplifier 63 amplifies the difference between the negative electrode voltage of the LED module 22 and the 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.

The dimming control circuit 62 converts a PWM (Pulse Width Modulation) signal transmitted from the wireless device 5 via the signal cable 52 to a dimming signal and outputs the dimming signal to the constant current circuit 61, as described later. The PWM signal is a voltage signal in which the dimming level is replaced with a duty ratio. The dimming level corresponds to the current value of the load current If supplied to the LED module 22 by the lighting device 1. 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. That is, when the duty ratio is 0 to 5%, the dimming level is set to 100%, and when the duty ratio is 98% or more (excluding 100%), the dimming level is set to 5% (lower limit). When the duty ratio is 5 to 98%, the dimming level decreases at a constant rate with respect to an increase in the duty ratio. However, when the duty ratio is 100%, the dimming level is set to 0%, meaning the LED module 22 is turned off.

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

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

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 difference (differential voltage Vd) between the dimming signal input from the dimming control circuit 62 and the voltage across resistor Rx (voltage proportional to the load current If).

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.

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.

The current mirror circuit 612 operates to make the drain current of the transistor TR2, i.e., the load current If flowing through the LED module 22, equal to the output current (target current) of the voltage-current conversion circuit 611.

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.

The start-up circuit 64 generates the control power supply voltage Vcc on behalf 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.

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 when the AC power supply 9 starts to supply AC voltage until the output voltage of the converter circuit 11 stabilizes.

When the AC power supply 9 starts to supply AC voltage, the control device 6 preferably controls the constant current circuit 61 so as to reduce the load current If to less than the rated value during the operation period of the start-up circuit 64. By operating the control device 6 as described above, it is possible to prevent the output current of the start-up circuit 64 and the output current (load current If) of the constant current circuit 61 from simultaneously increasing to near the maximum value. However, it is preferable that the control device 6 also operates in the same manner when the dimming level indicated by the PWM signal rises from 0% (LED module 22 is turned off) to any dimming level between several tens of percent and 100%.

The overcurrent detection circuit has 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, when an overcurrent flows through the switching element Q1 for some reason and the overcurrent detection circuit (comparator 66) detects the overcurrent, the control device 6 stops the converter circuit 11 to protect the lighting device 1 from the overcurrent. It is preferable that the control circuit 60 resumes the output of the drive voltage Vg to operate the converter circuit 11 when the output voltage of the comparator 66 returns to a low level.

In addition, it is preferable that the constant current circuit 61 continue the operation of making 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 the operation of 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.

As shown in FIG. 4, the wireless device 5 includes a circuit block 50, a housing 51, a signal cable 52, a plug connector 53, etc. The circuit block 50 includes a circuit board 50A and a circuit cover 50B.

As shown in FIG. 5, the circuit block 50 has 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, a signal output terminal 505, and the like. 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 is formed with a conductor constituting the antenna 500. In addition, the second area is equipped with the wireless communication circuit 501, the wireless control circuit 502, the infrared communication circuit 503, the photocoupler 504, resistors R51 and R52, the signal output terminal 505, and the like, except for the antenna 500. The circuit cover 50B is formed in a box shape from a material that blocks electromagnetic waves, for example, 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.

The wireless communication circuit 501 receives a wireless signal received by the antenna 500, for example, a wireless signal using radio waves in the 920 MHz band as a medium. Furthermore, the wireless communication circuit 501 converts the received wireless signal (RF signal) into an intermediate frequency signal (IF signal) lower than the carrier frequency (920 MHz) and obtains a control command from the IF signal. The wireless signal is transmitted from a transmitter and transmits a control command for turning on/off the light source unit 2 and adjusting the dimming level. The wireless communication circuit 501 outputs the control command obtained from the wireless signal (IF signal) to the wireless control circuit 502. The wireless control circuit 502 is preferably composed of, for example, 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 also electrically connected to a pair of signal lines through which the control signal is transmitted. The input terminal of the photocoupler 504 and a current limiting resistor R51 are electrically connected in series to the wireless control circuit 502. In other words, the control signal transmitted to the signal line is input to the input terminal of the photocoupler 504 via the wireless control circuit 502.

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 the signal cable 52 and the 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 and the negative output terminal of the photocoupler 504 (the emitter of the phototransistor) are electrically connected by 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 by another electric wire 52B. Furthermore, 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 by 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 is at a low level when the input voltage to the photocoupler 504 is at a high level, and is at a high level when the input voltage to the photocoupler 504 is at a low level.

The infrared communication circuit 503 performs wireless communication using infrared rays as a medium. That is, the infrared communication circuit 503 receives (receives) an infrared signal with the infrared receiving element 503A mounted in the second area of the circuit board 50A, and outputs the setting information and control information obtained from the received infrared signal to the wireless control circuit 502. The setting information is, for example, unique identification information assigned to the transmitter that is the source 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, the so-called Electric Home Appliances Association format. In the Electric Home Appliances Association format, infrared rays with a peak value of 900 to 950 nm in wavelength are used, 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 is used.

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 obtains not only the control command but also the identification information of the transmitter from the wireless signal received by the antenna 500 and outputs it 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.

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

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 arranged side by side in the short direction, on two side walls facing each other in the longitudinal direction.

The cover 511 has a rectangular plate-shaped lid body 5110, two pairs of fixed legs 5111, and an antenna storage section 5112. The fixed legs 5111 are formed so as to protrude upward from both ends along the short side direction of the lid body 5110. The tips (upper ends) of these two pairs of fixed legs 5111 are provided with hook claws 51110 that protrude outward. The antenna storage section 5112 is formed in a flat rectangular box shape. The antenna storage section 5112 protrudes downward from the lower surface of the lid body 5110 and is formed integrally with the lid body 5110 so as to open on the upper surface of the lid body 5110. The antenna storage section 5112 has a through hole 5113 at the end in the longitudinal direction that penetrates the thickness direction (up and down direction) of the lid body 5110.

The body 510 and the cover 511 are joined by hooking two pairs of fixed legs 5111 of the cover 511 into four hook holes 5102 of the body 510. In the circuit block 50, the second area of the circuit board 50A to which the circuit cover 50B is attached is housed in the body 510, and the first area 50AA (antenna 500) of the circuit board 50A is housed in the antenna housing 5112. The through hole 5113 of the cover 511 faces the light receiving part of the infrared receiving element 503A mounted on the second area of the circuit board 50A. In other words, the infrared signal transmitted from the setting device (wireless remote controller) (not shown) is received (received) by the infrared receiving element 503A through the through hole 5113 of the housing 51 (cover 511).

As shown in FIG. 6, the wireless device 5 is attached to the bottom plate 210 of the mounting member 21. A rectangular opening 213 is provided at one end of the bottom plate 210 in the longitudinal direction (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 section 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 mounting member 21 with the antenna housing section 5112 protruding from the opening 213 to the lower surface side of the bottom plate 210 (see FIG. 6). In addition, 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.

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 frequency of the carrier waves of the radio signal and the infrared signal, the higher the possibility that the common mode noise will interfere with the radio signal and the infrared signal. Note that, for radio signals, the smaller the difference between the frequency of the IF signal (e.g., 720 kHz) and the frequency of the common mode noise, the higher the possibility that the common mode noise will interfere. 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. Note that 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 coincides with the switching frequency of the switching element Q1.

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 radio 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.

In this way, 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, which makes it possible to suppress malfunctions and non-operation of the remote control due to common mode noise.

When a boost chopper circuit and a buck converter circuit are provided as in the conventional example described in Patent Document 1, the frequency of the common mode noise coincides with the switching frequency of the boost chopper circuit. Moreover, since the switching frequency of the boost chopper circuit changes within a predetermined frequency range depending on the fluctuation of the input voltage and the dimming level, the frequency of the common mode noise also changes according to the change in the switching frequency. On the other hand, the cutoff frequency of the low-pass filter (filter for removing common mode noise) of the filter unit 13 changes depending on the variation in the constants of the circuit elements constituting the low-pass filter and the temperature characteristics. Therefore, if the switching frequency of the boost chopper circuit becomes lower than the cutoff frequency of the low-pass filter, it may become difficult for the filter unit 13 to remove the common mode noise.

In contrast, in the lighting device 1, the switching frequency of the 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, the lighting device 1 can suppress malfunctions and non-operation of the remote control due to common mode noise even in a situation where the cutoff frequency of the filter section 13 is prone to fluctuation.

As described above, the lighting device (1) according to the first aspect of the present disclosure includes a converter circuit (11) that supplies a direct current load current (If) to a light source (LED module 22) that is a load. The lighting device (1) according to the first aspect 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) a constant current. 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 wireless signals mediated by electromagnetic waves. The constant current circuit (61) makes the load current (If) match a target value indicated by one or more types of wireless signals.

The lighting device (1) according to the first aspect makes it difficult for common mode noise that coincides with the switching frequency of the switching element (Q1) to overlap with the carrier frequency of the wireless signal, thereby making it possible to suppress malfunctions and non-operation of the remote control caused by common mode noise.

The lighting device (1) according to the 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 the switching frequency when controlling the switching of the switching element (Q1).

The lighting device (1) according to the second aspect can further prevent malfunctions and non-operation of the remote control caused by common mode noise, since the common mode noise does not overlap with the carrier frequency of the wireless signal.

The lighting device (1) according to the 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, it is preferable that the one or more types of wireless signals include a first wireless signal (infrared signal) using infrared rays as a medium. It is preferable that the control circuit (60) is configured to perform switching control of the switching element (Q1) at a frequency higher than the carrier frequency of the first wireless signal.

The lighting device (1) according to the third aspect makes it possible to suppress malfunctions and non-operation of remote control using the first wireless signal, since the first wireless signal using infrared rays is less likely to interfere with common mode noise.

The lighting device (1) according to the 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 that uses radio waves as a medium. 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.

The lighting device (1) according to the fourth aspect makes it possible to suppress malfunctions and non-operation of remote control using the second wireless signal, since the second wireless signal, which is transmitted via radio waves, is less likely to interfere with common mode noise.

The light source unit (2) according to the fifth aspect of the present disclosure includes a 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).

The light source unit (2) according to the fifth aspect can suppress malfunctions and non-operation of remote control caused by common mode noise.

The light source unit (2) according to the 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 signal. 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 a long rectangular plate shape 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).

The light source unit (2) according to the sixth aspect allows the wireless device (5) to be placed in a location that is unlikely to affect the light emitted from the light source.

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

The lighting device (3) according to the seventh aspect can suppress malfunctions and non-operation of the remote control due to common mode noise.

REFERENCE SIGNS LIST 1 Lighting device 2 Light source unit 3 Lighting fixture 4 Fixture body 5 Wireless device 11 Converter circuit 21 Mounting member 22 LED module (light source)
60 Control circuit 61 Constant current circuit 210 Bottom plate Q1 Switching element If Load current

Claims (3)

A lighting device;
a light source that is turned on by the lighting device;
a wireless device that receives a wireless signal carried by radio waves through an antenna and generates a control signal for transmitting a target value indicated by the received wireless signal;
a mounting member to which the light source, the lighting device, and the wireless device are attached;
Equipped with
The lighting device includes:
a converter circuit for supplying a DC load current to the light source;
a control circuit that controls switching of a switching element included in the converter circuit;
a constant current circuit for making the load current a constant current;
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 element so as to perform voltage conversion and power factor correction in parallel, and to control the switching of the switching element at a frequency lower than a carrier frequency of the radio signal;
the constant current circuit causes the load current to coincide with the target value indicated by the wireless signal;
The control circuit is configured to fix a switching frequency when controlling the switching element,
the mounting member has a bottom plate formed in a long rectangular plate shape to which the lighting device and the wireless device are attached,
the lighting device is attached to the bottom plate at a position spaced apart from the wireless device along a longitudinal direction of the bottom plate,
the wireless device has a circuit board and the antenna made of a conductor formed on a surface of the circuit board, and is attached to one end of the bottom plate in a longitudinal direction;
Light source unit. The wireless device receives a wireless signal using infrared rays as a medium , and further generates a control signal for transmitting a target value indicated by the received wireless signal;
The control circuit is configured to control the switching of the switching element at a frequency higher than a carrier frequency of the wireless signal transmitted through the infrared rays .
The light source unit according to claim 1 . A light source unit according to claim 1 or 2;
A fixture body supporting the light source unit;
Equipped with
lighting equipment.

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