JP7065352B2 - LED lighting device and lighting equipment - Google Patents

Description

The present invention relates to an LED lighting device that lights a plurality of LED (Light Emitting Diode) loads having different emission colors.

Patent Document 1 discloses a lighting device capable of dimming and toning by sequentially switching and lighting a plurality of LEDs having different emission colors and adjusting the intensity and mixing ratio of each emission color.

Japanese Unexamined Patent Publication No. 2004-311635

However, according to the above-mentioned prior art, there is a problem that color flicker may occur as the darkness increases due to dimming, for example. Here, color flicker means that when a fast-moving object such as a fan wing exists under the illumination light, the individual emission color of the LED appears on the object and is perceived by a person. To say. If the color flickers intensely, it may cause discomfort or discomfort to the person.

Therefore, an object of the present invention is to provide an LED lighting device and a lighting fixture that reduce color flicker that tends to occur when the illumination light is dark due to dimming.

In order to solve the above problems, the LED lighting device of the present invention is an LED lighting device that lights a plurality of LED loads having different emission colors, and is a power supply circuit that supplies power to the plurality of LED loads and the plurality of LEDs. By sequentially and cyclically selecting one LED load from the load, the selector circuit that feeds the selected LED load from the power supply circuit and the plurality of LED loads within a cycle in which the selection of the plurality of LED loads makes a cycle. A control circuit for controlling the selection of the selector circuit is provided so that at least two power supply sections of the power supply sections fed from the power supply circuit are continuous for each of the LED loads.

According to the LED lighting device and the lighting fixture of the present invention, it is possible to reduce the color flicker that tends to occur when the illumination light is dark due to dimming.

FIG. 1 is a block diagram showing a configuration example of a lighting fixture having an LED lighting device according to the first embodiment. FIG. 2 is a diagram showing a current waveform of a lighting fixture having the LED lighting device according to the first embodiment. FIG. 3 is a diagram showing a circuit configuration example of a lighting fixture having the LED lighting device according to the first embodiment. FIG. 4 is a diagram showing a current waveform and a voltage waveform of each part of the lighting fixture having the LED lighting device according to the first embodiment. FIG. 5 is a diagram showing a current waveform of a lighting fixture having the LED lighting device according to the second embodiment. FIG. 6 is a diagram showing a current waveform of a lighting fixture having the LED lighting device according to the third embodiment. FIG. 7 is a diagram showing a current waveform and a timer output of a lighting fixture having the LED lighting device according to the fourth embodiment. FIG. 8A is a diagram showing an external example of a lighting fixture having an LED lighting device according to each embodiment. FIG. 8B is a diagram showing another appearance example of the lighting fixture having the LED lighting device according to each embodiment. FIG. 8C is a diagram showing still another appearance example of the lighting fixture having the LED lighting device according to each embodiment. FIG. 9 is a diagram showing a configuration of a lighting fixture of a comparative example. FIG. 10 is a diagram showing a current waveform of a lighting fixture of a comparative example.

(Knowledge that became the basis of the present invention)
The present inventor has found that the following problems arise with respect to the lighting device described in the "Background Techniques" column.

First, the lighting fixture according to the knowledge of the present inventor will be described as a comparative example.

FIG. 9 is a diagram showing a configuration of a lighting fixture of a comparative example according to the knowledge of the present inventor. The lighting fixture in the figure includes a power supply circuit 90, LED loads 91 to 94, and switching elements SW3 to SW6. The power supply circuit 90 has switching elements SW1, SW2, and an inductor L0, and is a so-called step-down chopper type DC-DC converter. The switching elements SW1 and SW2 are controlled so as to be exclusively turned on. The inductor L0 stores and discharges energy supplied from the connection points of the switching elements SW1 and SW2.

The LED loads 91-94 have different emission colors.

The switching elements SW3 to SW6 are controlled so as to be turned on in order within one cycle.

FIG. 10 is a diagram showing a current waveform of a lighting fixture of a comparative example. The vertical axis in the figure shows the inductor current. The inductor current is the output current of the power supply circuit 90 supplied to any LED load via the inductor L0. The horizontal axis shows time. The upper part of the figure shows a relatively bright state. The lower part of the figure shows the darkened state due to dimming. Further, the color α, the color β, the color γ, and the color δ indicate the emission colors of the LED loads 91 to 94. The emission colors of the LED loads 91 to 94 are, for example, red, green, blue, and white.

As shown in FIG. 10, the LED loads 91 to 94 make a round of light emission in the period Ts. This operation is called progressive lighting. Further, FIG. 10 shows a case where the period Ts is fixed and the switching frequencies of the switching elements SW3 to SW6 are fixed. When dimming is performed with the switching frequency fixed, the on-time is shortened and the pause section Tx is lengthened at the same time. When the rest section Tx becomes long, there is a problem that color flicker may be perceived by the human eye during progressive lighting.

Color flicker separates the individual emission colors when there is an object that moves quickly under the illumination light, for example, when the hand is swiftly waved under the illumination light, or when the fan blades are rotating. It is a phenomenon that can be seen. As for the color flicker, the longer the pause section Tx, the easier it is to see the colors separated on a rapidly moving object. Such color flicker may give a person a feeling of discomfort or discomfort.

In order to solve such a problem, the LED lighting device according to one aspect of the present invention is an LED lighting device that lights a plurality of LED loads having different emission colors, and is a power supply that supplies power to the plurality of LED loads. By sequentially and cyclically selecting one LED load from the circuit and the plurality of LED loads, the selection of the selected LED load is supplied from the power supply circuit, and the selection of the plurality of LED loads is completed. Within the cycle, the control circuit for controlling the selection of the selector circuit so that at least two power supply sections of the power supply sections fed from the power supply circuit for each of the plurality of LED loads are continuous is provided.

As a result, it is possible to reduce the appearance of separated emission colors on a rapidly moving object due to the continuous feeding section, that is, to reduce color flicker.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

It should be noted that all of the embodiments described below show a comprehensive or specific example of the present invention. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, steps, the order of steps, etc. shown in the following embodiments are examples, and are not intended to limit the present invention. Further, among the components in the following embodiments, the components not described in the independent claim indicating the highest level concept are described as arbitrary components.

(Embodiment 1)
[1.1 Configuration of LED lighting device and lighting equipment]
First, a configuration example of the lighting fixture 100 including the LED lighting device 30 according to the first embodiment will be described.

FIG. 1 is a block diagram showing a configuration example of a lighting fixture 100 having an LED lighting device 30 according to the first embodiment. The lighting fixture 100 in the figure includes an AC-DC power supply 10, a light source 20, and an LED lighting device 30.

The AC-DC power supply 10 is connected to, for example, a commercial 100V power supply, inputs AC power, and converts it into DC power.

The light source 20 includes LED loads 21 to 24. The LED loads 21 to 24 have different emission colors. The emission colors of the LED loads 21 to 24 are, for example, R (red), G (green), B (blue), and W (white).

The LED lighting device 30 is a device that lights a plurality of LED loads 21 to 24 having different emission colors. Therefore, the LED lighting device 30 includes a power supply circuit 31, a selector circuit 32, and a control circuit 33.

The power supply circuit 31 is a DC-DC converter that converts DC power from the AC-DC power supply 10 into DC power having different voltages and supplies the converted DC power to the light source 20.

The selector circuit 32 sequentially selects one LED load from the plurality of LED loads 21 to 24, thereby supplying power to the selected LED load from the power supply circuit 31. Therefore, the selector circuit 32 includes switching elements M3 to M6. Each of the switching elements M3 to M6 is connected in series with the LED load of any one of the plurality of LED loads 21 to 24. For example, in FIG. 1, the switching element M3 is connected in series with the LED load 21. The switching element M4 is connected in series with the LED load 22. The switching element M5 is connected in series with the LED load 23. The switching element M6 is connected in series with the LED load 24. These switching elements M3 to M6 are controlled to be exclusively turned on, for example. As a result, the LED loads 21 to 24 exclusively emit light, that is, one by one.

The control circuit 33 controls the selector circuit 32 so as to sequentially and cyclically select one LED load from the plurality of LED loads 21 to 24. At this time, the control circuit 33 feeds at least two of the power supply sections in which power is supplied from the power supply circuit 31 to each of the plurality of LED loads 21 to 24 within a cycle in which the selection of the LED loads 21 to 24 is completed. The selection of the selector circuit 32 is controlled so that the sections are continuous. For example, the control circuit 33 is provided with a rest section in which N power supply sections corresponding to N LED loads are continuous and no power is supplied to any of the LED loads immediately before and after the continuous N power supply sections. The selector circuit 32 may be controlled. Here, N is an integer of 3 or more, and FIG. 1 shows an example of N = 4.

FIG. 2 is a diagram showing an example of a current waveform of a lighting fixture 100 having an LED lighting device 30 according to the first embodiment. In FIG. 2, the power supply circuit 31 is a switching power supply including an inductor, and power is supplied to the LED loads 21 to 24 via the inductor. In the upper and lower stages of the figure, the vertical axis indicates the inductor current, that is, the current supplied from the power supply circuit 31 to any of the LED loads. The horizontal axis shows time. The upper part of the figure shows the waveform of the inductor current when the dimming factor is the first value. The lower part of the figure shows the waveform of the inductor current when the dimming factor is a second value smaller than the first value.

In FIG. 2, the section Ts indicates a cycle of lighting, which is a cycle in which the LED loads 21 to 24 cycle and light. Here, it is assumed that the one-round lighting cycle Ts is fixed. The colors α, β, γ, and δ indicate the emission colors of the LED loads 21 to 24, and are, for example, R (red), G (green), B (blue), and W (white).

The section Ta is a power supply section in which power is supplied from the power supply circuit 31 to the LED load 21 having the emission color α. Similarly, the sections Tb, Tc, and Td are power supply sections in which power is supplied from the power supply circuit 31 to the LED loads 22, 23, and 24.

The section Tx is a rest section in which no power is supplied to any LED load.

As shown in the figure, even if the dimming rate is changed as shown in the upper and lower rows, the paused section Tx is grouped into one section within the one-round lighting cycle Ts. The four power supply sections Ta to Tb are continuous and do not sandwich a rest section. In FIG. 2, color flicker can be reduced as compared with the comparative example shown in FIG.

Next, a more specific circuit example of the lighting fixture 100 having the LED lighting device will be described.

FIG. 3 is a diagram showing a circuit configuration example of a lighting fixture 100 having the LED lighting device 30 according to the first embodiment. As shown in FIG. 3, the luminaire 100 includes a light source 20 and an LED lighting device 30. However, in FIG. 3, the AC-DC power supply 10 shown in FIG. 1 is omitted.

The LED load 21 in the light source 20 is connected in series with the switching element M3, and its lighting is controlled by turning on and off the switching element M3. Become.

As a specific circuit example, the LED load 21 of FIG. 3 is connected in series with LEDs d1 to d3, a smoothing capacitor C2 connected in parallel with LEDs d1 to d3, and a parallel circuit including LEDs d1 to d3 and a smoothing capacitor C2. It also has a diode Da for preventing backflow and a resistor R2 for discharging when the power is turned off.

LEDs d1 to d3 are LED light emitting elements having the same light emitting color connected in series, and are connected in series with the switching element M3.

The smoothing capacitor C2 smoothes the inductor current supplied from the inductor L1 via the diode Da.

The diode Da prevents the current from flowing back from the smoothing capacitor C2 to the inductor L1. That is, the diode Da supplies the electric charge charged in the smoothing capacitor C2 only to the LEDs d1 to d3.

The resistor R2 has a high resistance value and discharges the electric charge of the smoothing capacitor C2 after the power is turned off from the on state.

The LED loads 22 to 24 have a configuration similar to that of the LED load 21 except that the emission colors are different. The LED load 21 may not be provided with the smoothing capacitor C2 and the diode Da for preventing backflow. The same applies to the LED loads 22 to 24.

The power supply circuit 31 in the LED lighting device 30 shows an example of a step-down chopper circuit in FIG. Specifically, the power supply circuit 31 includes a regulator 34, an HVIC (High Voltage Integrated Circuit) 35, input resistors R6 and R7, switching elements M1 and M2, and an inductor L1.

The regulator 34 receives DC power from the AC-DC power supply 10 and supplies a stabilized power supply voltage to the HVIC 35 and the control circuit 33.
The HVIC 35 supplies a gate signal to the switching elements M1 and M2 via the input resistors R6 and R7 according to the control of the control circuit 33. The gate signals of the switching elements M1 and M2 are activated exclusively at high speed and periodically.

The switching elements M1 and M2 are high-side transistors and low-side transistors for alternately connecting the DC voltage supplied from the AC-DC power supply 10 and the ground level to the inductor L1.

The inductor L1 stores and releases electrical energy according to the switching of the switching elements M1 and M2.

The selector circuit 32 includes input resistors R8 to R11 and switching elements M3 to M6.

The switching element M3 is connected in series with the LED load 21. A gate signal instructing on and off is input from the control circuit 33 to the gate of the switching element M3 via the input resistor R8. The switching element M3 is turned on and off according to the gate signal.

The switching elements M4 to M6 are also the same as the switching element M3. The control circuit 33 may be configured by an MCU (Micro Controller Unit or Micro Computer Unit) containing a processor, a memory, and a timer 36. The timer 36 measures various periodic times. For example, it is used to measure a cycle in which a plurality of LED loads 21 to 24 are selected, a feeding section, a resting section, and the like.

[1.2 Operation of LED lighting device and lighting equipment]
Next, an operation example of the lighting fixture 100 including the LED lighting device 30 according to the first embodiment will be described.

FIG. 4 is a diagram showing a current waveform and a voltage waveform of each part of the lighting fixture having the LED lighting device according to the first embodiment. The horizontal axis in the figure is the time axis. The vertical axis shows the current or voltage of each part. The inductor current IL indicates a current flowing through the inductor L1, that is, a current supplied from the power supply circuit 31 to any LED load. In the figure, the section in which the inductor current IL flows is a feeding section. The power supply section Ta indicates a section in which power is supplied from the power supply circuit 31 to the LED load 21. Similarly, the power supply sections Tb to Td indicate sections in which power is supplied from the power supply circuit 31 to the LED loads 22 to 24, respectively. Further, it is assumed that the emission colors of the LED loads 21 to 24 are R, G, B, and W.

The gate voltage V0 indicates a voltage input from the control circuit 33 to the gate of the switching element M1 via the HVIC 35. When the gate voltage Vo is at a high level, the switching element M1 is turned on. In the section where the gate voltage V0 is at a high level, the inductor current IL increases. At this time, the inductor L1 stores electric energy as magnetic energy. When the gate voltage V0 is at a low level, the switching element M1 is turned off. Immediately after the switching element M1 is switched from the on state to the off state, the inductor L1 releases the stored energy, that is, the inductor current IL is reduced to 0 by the back electromotive force of the inductor L1 and is supplied to the LED load 21. .. As a result, the feeding section Ta becomes longer than the high level section of the gate voltage V0. The inductor current IL is a triangular wave in the figure. The power supply section Ta in which the LED load is supplied from the power supply circuit 31 is equal to the section of one triangular wave.

The gate voltage Vr indicates a voltage input from the control circuit 33 to the gate of the switching element M3. When the gate voltage Vr is at a high level, the switching element M3 is turned on, that is, the corresponding LED load 21 is selected. Further, the high level section of the gate voltage Vr is controlled so as to include a high level section of the gate voltage V0 and include a triangular wave of the corresponding inductor current IL. The gate voltages Vg, Vb, and Vw are also the same as the gate voltage Vr. It should be noted that a dead time is provided between the high level sections of the gate voltages Vr, Vg, Vb, and Vw so that all four have low levels.

The LED current Ir indicates the current flowing through the LEDs d1 to d3 in the LED load 21. After the power supply section Ta, that is, even after the power supply from the power supply circuit 31 to the LED load 21 is completed, the LED current Ir does not become 0 and continues to flow while the current decreases. This is due to the smoothing capacitor C2 and the backflow prevention diode Da.

The LED currents Ig, Ib, and Iw are the same as those of the LED current Ir.

As shown in FIG. 4, the feeding sections Ta to Td are continuous. That is, the control circuit 33 controls the gate voltage V0 so that the feeding sections Ta to Td are continuous. The end point of the feeding section Ta is the time when the inductor current IL decreases and becomes 0. The control circuit 33 detects that the inductor current IL decreases to the 0 level, and when the 0 level is detected, the control circuit 33 raises the next pulse of the gate voltage V0. Further, the rest section Tx is grouped into one section within the one-round lighting cycle Ts.

In this way, since the feeding sections Ta to Td are continuous, color flicker can be reduced as compared with the case where there is a rest section between the feeding sections.

The toning for adjusting the color of the illumination light in the luminaire 100 is realized by changing the ratio of the brightness of the plurality of emission colors. Specifically, in FIG. 4, the control circuit 33 adjusts the color by changing the ratio of the four pulse widths of the gate voltage V0 in the feeding sections Ta to Td. Further, the dimming for adjusting the brightness of the illumination light in the luminaire 100 is realized by changing the brightness while keeping the ratio of the brightness of the plurality of emission colors constant. Specifically, in FIG. 4, the control circuit 33 adjusts by increasing or decreasing the four pulse widths of the gate voltage V0 while keeping the ratio of the four pulse widths of the gate voltage V0 in the feeding section Ta to td constant. It glows.

In the example shown in FIG. 4, the switching element M1 of the power supply circuit 31 is controlled to be turned on within the period in which any of the LED loads is selected by the selector circuit 32. That is, the switching operation in the power supply circuit 31 which is a switching power supply and the selection operation in the selector circuit 32 are synchronized.

It should be noted that the one-round lighting cycle Ts may be periodic at a speed that cannot be perceived by humans. For example, the frequency which is the reciprocal of the one-round lighting period Ts may be 100 Hz or more.

Here, "periodically at a speed that humans cannot perceive" means "do not allow humans to perceive flicker." Regarding measures against flicker of LED lighting, for example, "Regarding the enforcement of the revised government ordinance of the Electrical Appliance and Material Safety Law (enforced from July 1, 2012)" (Ministry of Economy, Trade and Industry), which is an explanatory document of the Electrical Appliance and Material Safety Law (PSE). The standards are shown in (according to the Product Safety Division of the Commercial Distribution Group). In "Countermeasures against flicker of optical output" on page 28 of the same explanatory document, the frequencies that bring about the effect equivalent to "the optical output does not feel flicker" are interpreted as follows. That is, in the same explanatory document, "the optical output does not feel flicker" is satisfied by (1) the repetition frequency is 100 Hz or more and there is no missing part in the optical output, and (2) the repetition frequency is 500 Hz. As mentioned above, it is interpreted as one of the above.

In the lighting fixture 100 of the present embodiment, since it is considered that there is no omission in the light output in the example of FIG. 4, it is considered that the above (1) may be satisfied. In this case, the frequency, which is the reciprocal of the one-round lighting period Ts, may be 100 Hz or higher.

Alternatively, in FIG. 3, when the configuration does not include the smoothing capacitors C2 to C5 and the like, it corresponds to the case where the optical output is missing, and it is considered that the above (2) may be satisfied. In this case, the frequency, which is the reciprocal of the one-round lighting period Ts, may be 500 Hz or higher.

As described above, the LED lighting device 30 according to the first embodiment is an LED lighting device 30 that lights a plurality of LED loads 21 to 24 having different emission colors, and supplies power to the plurality of LED loads 21 to 24. The power supply circuit 31 to be used, the selector circuit 32 that feeds the selected LED load from the power supply circuit 31 by sequentially selecting one LED load from the plurality of LED loads 21 to 24, and the plurality of LED loads. Within the cycle in which the selection of 21 to 24 is cycled, the selector circuit 32 is connected so that at least two of the power supply sections in which power is supplied from the power supply circuit 31 to each of the plurality of LED loads 21 to 24 are continuous. A control circuit 33 for controlling selection is provided.

As a result, color flicker can be reduced by making the feeding sections continuous. That is, when there is an object that moves quickly under the illumination light, it is possible to reduce the appearance of the emitted colors separated on the object.

Here, the plurality of LED loads are N (N is an integer of 3 or more) LED loads, and in the control circuit 33, N feeding sections corresponding to N LED loads are continuous and N continuous. The selector circuit 32 may be controlled so as to provide a pause section in which no LED load is supplied immediately before and after the power supply section of the above.

According to this, since the feeding section corresponding to any emission color is continuous with the feeding section corresponding to other emission colors, it is reduced that the emission colors appear to be separated on a rapidly moving object, that is, color flicker. Can be further reduced.

Here, the frequency, which is the reciprocal of the cycle in which the selection of the plurality of LED loads makes a round, may be 100 Hz or more.

According to this, it is possible to make it difficult for a person to perceive flicker due to periodic light emission of a plurality of LED loads.

Here, the power supply circuit 31 is a switching power supply including the inductor L1, and may supply power to a plurality of LED loads 21 to 24 via the inductor L1.

According to this, it is possible to reduce the size, efficiency and cost of the power supply circuit.

Here, the control circuit 33 may synchronize the switching operation in the power supply circuit 31, which is a switching power supply, with the selection operation in the selector circuit 32.

Here, the selector circuit 32 includes a plurality of switching elements M3 to M6, and each of the plurality of switching elements M3 to M6 is connected in series with an LED load of any of the plurality of LED loads 21 to 24. The control circuit 33 may sequentially and cyclically select the corresponding LED load by sequentially turning on one switching element from the plurality of switching elements M3 to M6.

According to this, the selector circuit 32 can be operated at high speed with a simple circuit configuration.

Here, the cycle in which the selection of the plurality of LED loads 21 to 24 goes around may be constant regardless of the dimming rate.

According to this, dimming can be facilitated.

Further, the lighting fixture 100 according to the first embodiment includes the above-mentioned LED lighting device 30 and a plurality of LED loads 21 to 24.

Here, each of the plurality of LED loads 21 to 24 includes one or more LEDs d1 and the like, a smoothing capacitor C2 connected in parallel with one or more LEDs, and one or more LEDs and a smoothing capacitor C2 in parallel. It may have a backflow prevention diode Da connected in series with the circuit.

The combination of emission colors of the LED loads 91 to 94 is not limited to red, green, blue, and white.

(Embodiment 2)
In the first embodiment, an example in which the resting sections are combined into one section within the one-round lighting cycle Ts has been described. In the second embodiment, an example in which a rest section is provided immediately before and after at least one feeding section and the other feeding sections are continuous will be described.

[2.1 Configuration of LED lighting device and lighting equipment]
The configuration of the luminaire 100 according to the second embodiment may be the same as that of FIGS. 1 and 3. However, the control performed by the selector circuit 32 by the control circuit 33 is different. The differences will be mainly described below.

The control circuit 33 controls the selector circuit 32 so as to provide a pause section in which no LED load is fed immediately before and after at least one feeding section. In other words, the control circuit 33 controls the selector circuit 32 so that not all the feeding sections corresponding to the plurality of LED loads are continuous, but at least two rest sections exist. The above-mentioned at least one feeding section may be, for example, a feeding section of a white LED load. That is, a pause section may be provided immediately before and after the feeding section of the white LED load.

The LED loads 21 to 24 do not have to be four LED loads, but may be composed of three or more LED loads.

[2.2 Operation of LED lighting device and lighting equipment]
Next, an operation example of the lighting fixture 100 including the LED lighting device 30 according to the second embodiment will be described.

FIG. 5 is a diagram showing a current waveform of a lighting fixture 100 having the LED lighting device 30 according to the second embodiment. The figure is different from FIG. 2 in that the rest section Tx is provided immediately before and after the power supply section Td of the color δ. Hereinafter, the differences will be mainly described.

In FIG. 5, the three feeding sections Ta, Tb, and Tc of the color α, the color β, and the color γ are continuous, and the feeding section Td of the color δ is not continuous with the other feeding sections. Rest sections Tx and Ty are provided immediately before and after the power supply section Td of the color δ.

Here, the color δ may be white. In FIG. 5, it is considered that the color δ is more likely to cause color flicker than other colors, but the discomfort perceived by humans is different from the case where the other primary colors appear to be separated even if the white color appears to be separated. small.

As described above, in the LED lighting device 30 according to the second embodiment, the plurality of LED loads 21 to 24 are composed of three or more LED loads, and the control circuit 33 immediately before and immediately after at least one feeding section. In addition, the selector circuit 32 is controlled so as to provide a rest section in which power is not supplied to any of the LED loads.

Even with this configuration, since there is a continuous feeding section, it is possible to reduce color flicker.

Here, the at least one LED load corresponding to at least one feeding section may include an LED load that emits light in white.

According to this, even if the white emission color appears to be separated on a rapidly moving object, the discomfort of color flicker is smaller than that of other primary colors, so there are pause sections immediately before and after the power supply section corresponding to white. However, it is possible to prevent color flicker.

The resting section Tx may have the same length as the resting section Ty, or may have a different length.

(Embodiment 3)
In the first embodiment, an example in which the resting sections are combined into one section within the one-round lighting cycle Ts has been described. In the third embodiment, an example in which each feeding section is continuous with at least one other feeding section and two or more resting sections are provided will be described.

[3.1 Configuration of LED lighting device and lighting equipment]
The configuration of the luminaire 100 according to the third embodiment may be the same as that of FIGS. 1 and 3. However, the control performed by the selector circuit 32 by the control circuit 33 is different. The differences will be mainly described below.

It is assumed that the light source 20 includes N LED loads. It is assumed that N = N1 + N2 (N is an integer of 4 or more, N1 is an integer of 2 or more, and N2 is an integer of 2 or more). 1 and 3 are examples of N = 4.

The control circuit 33 controls the selector circuit 32 so as to realize the following (a) to (d). (A) N1 power supply sections corresponding to N1 LED loads are continuous. (B) N2 feeding sections corresponding to N2 LED loads are continuous. (C) Immediately before and after the continuous N1 power supply section corresponding to the N1 LED load, a pause section in which no LED load is supplied is provided. (D) A pause section is provided immediately before and after the continuous N2 feeding section corresponding to the N2 LED load.

[3.2 Operation of LED lighting device and lighting equipment]
Next, an operation example of the lighting fixture 100 including the LED lighting device 30 according to the third embodiment will be described.

FIG. 6 is a diagram showing a current waveform of a lighting fixture 100 having the LED lighting device 30 according to the third embodiment. The figure shows the case of N = 4, N1 = 2, and N2 = 2. The figure is mainly different from FIG. 2 in that a pause section Tx is provided between the power supply section Tb of the color β and the power supply section Tc of the color γ. Hereinafter, the differences will be mainly described.

In FIG. 6, (a) N1 power supply sections Ta and Tb corresponding to N1 LED loads 21 and 22 are continuous. (B) N2 power supply sections Tc and Td corresponding to N2 LED loads 23 and 24 are continuous. (C) Immediately before and immediately after the continuous N1 power supply sections Ta and Tb corresponding to the N1 LED loads 21 and 22, rest sections Ty and Tx in which no LED load is supplied are provided. (D) Rest sections Tx and Ty are provided immediately before and after the continuous N2 power supply sections Tc and Td corresponding to the N2 LED loads 23 and 24.

In the example of FIG. 6, since the color α and the color β have continuous feeding sections Ta and Tb, color separation is unlikely to occur on a rapidly moving object. As for the color γ and the color δ, since the feeding sections Tc and Td are continuous, color separation is unlikely to occur on a rapidly moving object. Since the color β and the color γ sandwich the pause section Tx between the feeding sections Tb and Tc, color separation between the color mixture of the color α and the color β and the color mixture of the color γ and the color δ may occur. , Color β and color γ are unlikely to occur.

As described above, in the LED lighting device 30 according to the third embodiment, the plurality of LED loads 21 to 24 are N LED loads, and N = N1 + N2 (N is an integer of 4 or more, N1 is an integer of 2 or more, When N2 is an integer of 2 or more), in the control circuit 33, the N1 power supply section corresponding to the N1 LED load is continuous, and the N2 power supply section corresponding to the N2 LED load is continuous. Immediately before and after the continuous N1 power supply section corresponding to the N1 LED load, a pause section in which no LED load is supplied is provided, and the continuous N2 power supply section corresponding to the N2 LED load is provided. The selector circuit 32 is controlled so as to provide a rest section immediately before and after.

According to this, it is possible to reduce color flicker even if all the feeding sections are not continuous.

(Embodiment 4)
In the fourth embodiment, an example of counting the one-round lighting cycle by using the timer 36 will be described.

[4.1 Configuration of LED lighting device and lighting equipment]
The configuration of the lighting fixture 100 according to the fourth embodiment may be the same as that of FIG. However, the control circuit 33 is composed of an MCU (Micro Controller Unit or Micro Computer Unit) including a processor, a memory, and a timer 36. The timer 36 is used to count the length of the cycle in which the selection of the plurality of LED loads 21 to 24 goes around.

[4.2 Operation of LED lighting device and lighting equipment]
Next, an operation example of the lighting fixture 100 including the LED lighting device 30 according to the fourth embodiment will be described.

FIG. 7 is a diagram showing a current waveform of a lighting fixture 100 having the LED lighting device 30 according to the fourth embodiment. The figure is an example of the same lighting operation as in FIG. 2, and the one-round lighting cycle is fixed by the timer 36. As shown in the lower part of FIG. 7, the timer 36 is programmed to output a signal indicating a time-out each time the cycle lighting cycle Ts elapses. The control circuit 33 controls the selector circuit 32 so that the LED load 21 to the LED load 24 are turned on once each time a timeout occurs.

As described above, in the LED lighting device 30 according to the fourth embodiment, the control circuit 33 is composed of a microcomputer having a timer 36, and the timer 36 is used to determine the length of the cycle in which the selection of a plurality of LED loads goes through. May be counted.

According to this, in the control of the selector circuit 32 by the control circuit 33, the cycle lighting cycle can be flexibly and easily fixed, and the periodic control can be facilitated.

The timer 36 may count not only the cycle lighting cycle Ts but also the feeding section Ta to Td and the resting section Tx. The timer 36 may be configured to include one timer circuit or may be configured to include a plurality of timer circuits.

(Embodiment 5)
In the fifth embodiment, an example of the lighting fixture 100 including the LED lighting device 30 according to each of the above embodiments will be described with reference to FIGS. 8A to 8C.

FIG. 8A is a diagram showing an external example of a lighting fixture 100 having an LED lighting device 30 according to each embodiment. FIG. 8A shows the appearance of the downlight 100a as an example of the lighting fixture 100.

The downlight 100a includes a circuit box 101a, a lamp body 102a, and a wiring 103a. The circuit box 101a is a housing for accommodating all or a part of the LED lighting device 30 according to each of the above embodiments. The lamp body 102a is a lamp body equipped with a light source 20. The wiring 103a electrically connects the circuit box 101a and the light source 20 in the lamp body 102a.

FIG. 8B is a diagram showing another appearance example of the luminaire 100 having the LED lighting device 30 according to each embodiment. FIG. 8B shows the appearance of the spotlight 100b as an example of the lighting fixture 100. The spotlight 100b includes a circuit box 101b, a lamp body 102b, and wiring 103b. The circuit box 101b, the lamp body 102b, and the wiring 103b are the same as the circuit box 101a, the lamp body 102a, and the wiring 103a of FIG. 8A.

FIG. 8C is a diagram showing still another appearance example of the luminaire 100 having the LED lighting device 30 according to each embodiment. FIG. 8C shows the appearance of the spotlight 100c as an example of the lighting fixture 100. The spotlight 100c includes a circuit box 101c and a lamp body 102c. These are also the same as the circuit box 101a and the lamp body 102b in FIG. 8A.

Also in the fifth embodiment, the same effect as that of each of the above-mentioned embodiments can be obtained.

The LEDs d1 to d12 in the light source 20 may be not only a so-called light emitting diode but also a solid light emitting element such as an organic EL light emitting diode (OLED: Organic Light Emitting Diode) or a laser light emitting device.

Although the LED lighting device according to one or more aspects of the present disclosure has been described above based on the embodiment, the present disclosure is not limited to this embodiment. As long as it does not deviate from the gist of the present disclosure, various modifications that can be conceived by those skilled in the art are applied to the present embodiment, and a form constructed by combining components in different embodiments is also included in the scope of the present disclosure. You may.

21, 22, 23, 24 LED load 30 LED lighting device 31 Power supply circuit 32 Selector circuit 33 Control circuit)
36 Timer 100 Lighting equipment C2, C3, C4, C5 Smoothing capacitors d1 to d12 LED
Da, Db, Dc, Dd Diode L1 Inductor M3, M4, M5, M6 Switching element

Claims (10)

An LED lighting device that lights multiple LED (Light Emitting Diode) loads with different emission colors.
A power supply circuit that supplies power to the plurality of LED loads, and
A selector circuit that feeds the selected LED load from the power supply circuit by sequentially and cyclically selecting one LED load from the plurality of LED loads.
Within the cycle in which the selection of the plurality of LED loads is cycled, the selector circuit is configured so that at least two of the power supply sections supplied from the power supply circuit to each of the plurality of LED loads are continuous. Equipped with a control circuit to control the selection
The selector circuit includes a plurality of switching elements.
Each of the plurality of switching elements is connected in series with the LED load of any one of the plurality of LED loads.
The control circuit sequentially and cyclically selects the corresponding LED load by turning on one switching element sequentially from the plurality of switching elements.
The cycle in which the selection of the plurality of LED loads goes through is constant regardless of the dimming rate.
The length of the feeding section changes according to the dimming rate.
LED lighting device. The plurality of LED loads are composed of three or more LED loads.
The LED lighting device according to claim 1, wherein the control circuit controls the selector circuit so as to provide a pause section in which no LED load is supplied immediately before and after at least one power supply section. The LED lighting device according to claim 2, wherein the at least one LED load corresponding to the at least one feeding section includes an LED load that emits light in white. The plurality of LED loads are N LED loads.
When N = N1 + N2 (N is an integer of 4 or more, N1 is an integer of 2 or more, and N2 is an integer of 2 or more)
The control circuit is
N1 power supply sections corresponding to N1 LED load are continuous,
N2 power supply sections corresponding to N2 LED loads are continuous,
Immediately before and after the continuous N1 power supply section corresponding to the N1 LED load, a pause section in which no LED load is supplied is provided.
The LED lighting device according to claim 1, wherein the selector circuit is controlled so as to provide the pause section immediately before and after the continuous N2 power supply section corresponding to the N2 LED load. The plurality of LED loads are N (N is an integer of 3 or more) LED loads.
The control circuit is
N power supply sections corresponding to N LED loads are continuous,
The LED lighting device according to claim 1, wherein the selector circuit is controlled so as to provide a pause section in which no LED load is supplied immediately before and after the continuous N power supply sections. The LED according to any one of claims 1 to 5, wherein the control circuit is composed of a microcomputer having a timer, and counts the length of a cycle in which the selection of the plurality of LED loads goes through using a timer. Lighting device. The LED lighting device according to any one of claims 1 to 6, wherein the frequency, which is the reciprocal of the cycle in which the selection of the plurality of LED loads goes through, is 100 Hz or more. The LED lighting device according to any one of claims 1 to 7, wherein the power supply circuit is a switching power supply including an inductor, and supplies power to the plurality of LED loads via the inductor. The LED lighting device according to any one of claims 1 to 8 .
A luminaire with the plurality of LED loads. Each of the plurality of LED loads
With one or more LEDs
A smoothing capacitor connected in parallel with one or more LEDs,
The luminaire according to claim 9 , further comprising a parallel circuit including the one or more LEDs and the smoothing capacitor and a backflow prevention diode connected in series.

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