JP2009099627A - Led luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED luminaire allowing appropriate wire connection even if a connector for reverse connection prevention is not used and the number of LEDs is not increased. <P>SOLUTION: The LED luminaire includes: input terminals 1a and 1b for inputting a D.C. voltage thereto; one or more light emitting diodes 2a-2h; and an LED mounting board 3 for mounting the input terminals 1a and 1b and the light emitting diodes 2a-2h thereon. In the LED luminaire, a rectifying device DB1 connected to rectify a current from anodes to cathodes of the light emitting diodes 2a-2h is mounted between the input terminals 1a and 1b and the light emitting diodes 2a-2h on the LED mounting board 3. The rectifier device DB1 is arranged substantially at the center of a region of the LED mounting board 3 where the light emitting diodes are mounted. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an LED lighting apparatus using a light emitting diode (hereinafter referred to as LED).

  FIG. 8 is a schematic configuration diagram of a conventional LED lighting apparatus. A light diffusing plate 9 is attached to the opening of the instrument housing 8 embedded in the ceiling surface 7, and the LED 2 is disposed behind the light diffusing plate 9. A power input lead wire 61 is drawn out from an LED mounting board 3 formed of a printed board on which a plurality of LEDs 2 are mounted, and a connector 71 is attached to the end of the lead wire 61. In addition, an AC-DC converter that outputs a DC voltage with an AC power line 12 connected to a commercial power supply as an input is mounted, and a similar output lead wire 62 is also connected to the output end of the DC power unit 14 that emits light from the LED 2. The connector 72 is attached to the end portion.

  Here, like the diode, the LED 2 must pass current from the anode to the cathode. Since the output from the DC power supply unit 14 has positive and negative voltage polarities, the LED 2 does not emit light unless a positive output is connected to the anode side of the LED 2 and a negative output is connected to the cathode side. Thus, the lead wires 61 and 62 have polarity, and the pair of lead wires 61 for power input to the LED mounting substrate 3 and the pair of lead wires 62 for output from the DC power supply unit 14 are polar. In order not to make a mistake, the connectors 71 and 72 cannot be reversely connected. For the connectors 71 and 72, for example, an SL series made by Japanese crimp terminal is used.

In addition, as disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2000-101136), a configuration in which a plurality of LEDs are connected so that the polarities of the anode and the cathode are alternately reversed in order to be lit by a commercial power supply has been proposed. ing. According to the configuration disclosed in Patent Document 1, a connection error is prevented from occurring by alternately connecting the polarities of LEDs in the reverse direction without using a connector or the like for preventing reverse connection.
JP 2000-101136 A

  When the connectors 71 and 72 for preventing reverse connection are used as in the conventional example of FIG. 8, terminals on the male side and female side are required, and the connectors 71 and 72 for connecting the lead wires 61 and 62 to the lead wires 61 and 62 are required. Work becomes necessary, and this becomes a factor that increases the cost. That is, in order to securely connect the lead wires 61 and 62 to the connectors 71 and 72, a male-side pin contact and a female-side socket contact are necessary, and the conductive portion is exposed by itself, so that The housing portions of both contacts are required, and the number of parts increases.

  In addition, with the configuration shown in Patent Document 1, a connector for preventing reverse connection is not necessary. However, compared to DC lighting, AC lighting emits only half a power cycle. In order to ensure, twice as many LEDs are required. Therefore, even in this method, a large number of LEDs are required, which causes a cost increase.

  This invention is made | formed in view of the above points, and it is a subject to provide the LED lighting fixture which can perform an appropriate connection, without using the connector for reverse connection prevention, and without increasing the number of LED. And

  In order to solve the above problems, the invention of claim 1 is, as shown in FIG. 1, input terminals 1a and 1b to which a DC voltage is applied, at least one light emitting diode 2a to 2h, and the input terminal 1a. , 1b and the first printed circuit board 3 on which the light emitting diodes 2a to 2h are mounted, between the input terminals 1a and 1b and the light emitting diodes 2a to 2h, from the anode of the light emitting diodes 2a to 2h to the cathode The rectifying element DB1 connected so as to rectify is mounted on the first printed circuit board 3.

  According to a second aspect of the present invention, in the first aspect of the present invention, the rectifying element DB1 is connected to the cathode of the light emitting diodes 2a to 2h even if the polarity of the DC voltage applied to the input terminals 1a and 1b changes. It is connected so that it may rectify.

  The invention of claim 3 is the invention of claim 1 or 2, wherein the rectifier element DB1 is a diode bridge component in which a plurality of rectifier diodes are housed in one package.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the DC voltage applied to the input terminals 1a and 1b is an output of the AC-DC converter 4 that converts a commercial AC power source into a DC voltage. As shown in FIG. 2, the electronic component of the AC-DC converter 4 is mounted on the second printed circuit board 5, and the first printed circuit board 3 and the second printed circuit board 5 are electrically conductive. 6a and 6b are connected.

  The invention of claim 5 is characterized in that, in the invention of claim 4, the first printed circuit board 3 and the second printed circuit board 5 are housed in the same instrument housing 8 (FIG. 2).

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the rectifying element DB1 is disposed at a substantially central portion of a region where the light emitting diode is mounted on the first printed circuit board 3. (FIGS. 3, 5, and 7).

  According to the first aspect of the present invention, a reverse voltage is not applied to the LED even when reversely connected, and the LED can be prevented from being broken.

  According to the invention of claim 2, there is an effect that the LED can be normally lit even when reverse connection is made.

  According to the invention of claim 3, by using the diode bridge component, the component cost can be reduced, the wiring between the plurality of rectifier diodes can be omitted, and the assembly cost can also be reduced.

  According to the fourth aspect of the present invention, an LED lighting apparatus that can be turned on by a commercial AC power source can be realized, so that it can be applied to a wide range of indoor lighting and outdoor lighting.

  According to the fifth aspect of the present invention, since the power supply unit and the light emitting unit are integrated, it is easy to construct the lighting fixture on site. In addition, it is not necessary to consider the plus and minus of wiring when connecting between boards during manufacturing, maintenance and inspection of lighting fixtures, and it is not necessary to use a misconnection prevention type connector, etc. The instrument can be configured.

  According to the invention of claim 6, even if the rectifying element is mounted on the first printed circuit board for LED mounting, the rectifying element hardly forms a shadow, so that a substantially uniform light region is formed in the vicinity of the rectifying element. It becomes possible to do.

The details of the present invention will be described below with reference to the illustrated embodiments.
(Embodiment 1)
FIG. 1 is a circuit diagram of an LED lighting apparatus according to the first embodiment of the present invention. In the figure, 3 is an LED mounting substrate, and 4 is an AC-DC converter. The input terminals 1a and 1b of the LED mounting board 3 and the output terminal CON2 of the AC-DC converter 4 are connected by lead wires 6a and 6b. The input terminal CON1 of the AC-DC converter 4 is connected to an AC power supply voltage (for example, AC100V, 50/60 Hz) from the commercial power supply Vs.

  FIG. 2 is a cross-sectional view showing an example of the mounting structure of the LED lighting apparatus according to this embodiment. The instrument housing 8 embedded in the ceiling surface 7 is made of a metal cylinder opened at the lower end, and the lower end open portion is covered with a light diffusion plate 9. The LED mounting substrate 3 is disposed so as to face the light diffusing plate 9.

  In this embodiment, the AC-DC converter 4 of FIG. 1 and the LED mounting substrate 3 are housed in the same instrument housing 8. The second printed circuit board 5 on which the electronic components of the AC-DC converter 4 are mounted is supported on the back side of the top plate of the instrument housing 8 by the support member 10. A connection member 11 to the commercial power source Vs is provided on the upper surface side of the top plate of the instrument housing 8. Reference numeral 12 denotes an AC power line.

  In the case of an LED lighting fixture, the temperature of the LED greatly affects the light output, so that the heat generated by the LED needs to be radiated to the fixture housing 8. For this reason, the AC-DC converter 4 and the LED mounting substrate 3 are separated by the heat radiating plate 13 that is thermally coupled to the instrument housing 8, so that the connection work using the lead wires 6 a and 6 b is necessary. In the present embodiment, when connecting the lead wires 6a and 6b during the assembly operation of the lighting fixture, since it does not depend on the polarity of the output terminal CON2 of the AC-DC conversion device 4, the plus and minus of the wiring in manufacturing. Thus, it is not necessary to use an erroneous connection prevention type connector or the like, and the lighting apparatus can be configured at low cost.

  FIG. 3 is a front view of the LED mounting substrate 3 as viewed from the light diffusion plate 9 side. Eight LEDs 2a to 2h are mounted on the LED mounting substrate 3, and the LED 2a to LED 2h are connected in series from the anode to the cathode. When a positive voltage is applied to the anode side of the LED 2a and a negative voltage is applied to the cathode side of the LED 2h, the LEDs 2a to 2h emit light. When a voltage equal to or greater than the total of the forward voltages Vf of the LEDs 2a to 2h is applied, a light flux can be obtained from the LEDs according to the value of the flowing current. Since the forward voltage Vf is generally about 3.5V, if eight of them are connected in series, they can be lit at a DC voltage of 8 × 3.5V or more.

  A rectifying element DB1 is mounted on the LED mounting substrate 3, and a diode is interposed between the lead wires 6a and 6b connected to the power input unit 1 (input terminals 1a and 1b in FIG. 1) and the series circuit of the LEDs 2a to 2h. A rectifying element DB1 for full-wave rectification made of a bridge component is connected, and is wired so that a current flows in the forward direction through the series circuit of the LEDs 2a to 2h regardless of the polarity to which the lead wires 6a and 6b are connected. Yes. The power input unit 1 is inexpensive as if the lead wires 6a and 6b are inserted into the front surface side from the back side through through holes (vias) provided in the LED mounting substrate 3 and soldered to the land (copper foil). A simple structure is also acceptable.

  The circuit configuration of the AC-DC converter 4 will be described with reference to the circuit diagram of FIG. The input filter unit 40 of the AC-DC converter 4 is connected to the commercial power source Vs. The input filter unit 40 includes a fuse FUSE, a capacitor C1, and a line filter LF. The fuse FUSE is connected in series to one end of the commercial power supply Vs, and the capacitor C1 and the line filter are connected in parallel with the other end of the commercial power supply Vs and the output end of the fuse FUSE. LF is connected.

  A rectifier element DB2 and a capacitor C2 are connected in parallel to the output of the input filter section 40, and a series circuit of a transformer T1 and a switching element Q1 is connected in parallel with the capacitor C2. A capacitor C4 is connected in parallel to both ends of the switching element Q1. A diode D1 is connected to the high potential side of the secondary winding side of the transformer T1, a capacitor C3 and an output terminal CON2 are connected in parallel via the diode D1, and the low potential side of the output terminal CON2 and the capacitor C3 A resistor R1 for converting the output current Io into a voltage value is connected between the negative electrodes.

  The first control circuit 41 is provided on the primary side of the transformer T1, and outputs a switching signal of the switching element Q1 according to an input value from the feedback terminal FB. The second control circuit 42 is provided on the secondary side of the transformer T1, and receives a value obtained by converting the output current Io into a voltage by the resistor R1, and generates a feedback signal. A light emitting element of the photocoupler PC1 is connected to the output of the second control circuit 40, and a feedback input terminal FB of the first control circuit 41 is connected to the light receiving element of the photocoupler PC1.

  The primary side capacitor C2 and the secondary side capacitor C3 of the transformer T1 are both aluminum electrolytic capacitors. Although not shown, capacitors for smoothing the control voltages Vcc of the first control circuit 21 and the second control circuit 22 are used, and these are limited-life parts such as aluminum electrolytic capacitors. It is. It is known that an aluminum electrolytic capacitor has a shorter life when the temperature rises.

  The circuit operation will be described below. The AC-DC conversion device 4 is a so-called flyback type DC power supply device, and is a partial resonance type having a capacitor C4 connected in parallel to the switching element Q1. The voltage input from the commercial AC power supply Vs is full-wave rectified by the rectifier element DB2 via the input filter part 40 via the input terminal CON1. The full-wave rectified voltage is smoothed by the capacitor C2, and the voltage is applied to the series circuit of the transformer T1 and the switching element Q1. When the switching element Q1 is closed, a current flows through the transformer T1 and is charged as magnetic energy. When the switching element Q1 is opened, the magnetic energy is output to the output side via the secondary winding and the diode D1. To be released. The output voltage is smoothed by the capacitor C3 and output via the output terminal CON2. When the voltage output from the AC-DC converter 4 is supplied to the LED mounting substrate 3 and rectified by the rectifying element DB1, the voltage is equal to or higher than the total of the forward voltages Vf of the LEDs 2a to 2h. The LEDs 2a to 2h are lit.

  The current flowing at that time flows to the resistor R1 through the output terminal CON2, and the resistor R1 generates a voltage corresponding to the current. This voltage is monitored at the IN terminal of the control integrated circuit IC2 (for example, NJM2146 manufactured by New Japan Radio Co., Ltd.) in the second control circuit 42, and is compared with the reference voltage of the reference voltage terminal REF, whereby the LEDs 2a to 2h are operated. The output of the OUT terminal of the second control circuit 42 is determined according to the flowing current. This output determines the current flowing through the light emitting element of the photocoupler PC1 connected to the control voltage Vcc. The control voltage is fed back from the light receiving element in the photocoupler PC1 to the feedback terminal FB of the control integrated circuit IC1 of the first control circuit 40 (for example, MR 1722 manufactured by Shindengen Co., Ltd.). At this time, the ON width of the switching element Q1 is determined according to the control voltage input to the feedback terminal FB. By operating in this way, control is performed to keep the current flowing through the LEDs 2a to 2h constant.

  Since the rectifier element DB1 is provided on the input side of the LED mounting board 3, the output terminal CON2 of the AC-DC converter 4 and the lead wires 6a and 6b of the LED mounting board 3 are connected to the input terminals 1a and 1b. On the other hand, even if it is connected to a different polarity, it is rectified, and the LEDs 2a to 2h can be lit. Therefore, a connector for preventing reverse connection is not required on the input side of the LED mounting substrate 3 as in the prior art. Further, since the number of LEDs may be equal, the number of parts can be reduced as compared with the conventional example of Patent Document 1, and there is a merit in terms of cost.

  In this embodiment, the flyback type DC power source has been described, but it goes without saying that the same effect can be obtained if the DC power source outputs a DC voltage regardless of the type. Further, although eight LED connection in series has been described for the LED mounting substrate, it may be connected in parallel as long as the directions of the anode and the cathode are the same regardless of the number. In this example, a diode is used as a rectifying element, but any type of element can be used as long as it has an equivalent effect. For example, a Zener diode or the like may be used.

(Embodiment 2)
FIG. 4 is a perspective view showing a schematic configuration of Embodiment 2 of the present invention. The circuit configuration may be the same as in FIG. In this embodiment, an example of a case in which the DC power supply unit 14 that is a housing that houses the AC-DC converter 4 and the luminaire main body 21 including the LED mounting substrate 3 on which the plurality of LEDs 2 are mounted is separated. It is.

  In this embodiment, since the luminaire main body 21 and the DC power supply unit 14 can be separately arranged, the luminaire main body 21 is attached at a high place like the tip of the pole 20, and the DC power supply unit 14 is attached near the ground. In addition, since it is not necessary to consider the polarity of the output lead wires 6a and 6b of the DC power supply unit 14, the wiring work can be easily performed at the installation site.

  FIG. 5 shows a mounting form in which a plurality of LEDs 2 a to 2 j are arranged in a line on the LED mounting substrate 3. In this example, the rectifying element DB1 and the power input unit 1 (input terminals 1a and 1b in FIG. 1) are arranged in the approximate center of the LED mounting board 3, and a light diffusion plate is arranged in front of the plurality of LEDs 2a to 2j. As a result, the rectifying element DB1 receives light from the left and right, so that there is an effect that the rectifying element DB1 is less likely to be a shadow. When the rectifying element DB1 is arranged on the end face of the substrate, a shadow of the rectifying element DB1 is generated on the end face portion, so that a long line-shaped instrument cannot be uniformly emitted. However, by using the mounting form of FIG. Can be seen.

  In the present embodiment, 10 LEDs are divided into 5 pieces, but a configuration in which a substantially uniform light region can be formed in the vicinity of the rectifying element DB1 regardless of the number of LEDs. Then, it goes without saying that there is no difference in effect.

  Alternatively, the LED mounting board may be a double-side mounting type printed board, the LED may be mounted on the front surface, the rectifying element DB1 may be mounted on the back surface, and both may be connected by a through hole of the printed board. In this case, the LEDs can be arranged also on the mounting portion of the rectifying element DB1 in FIG.

(Embodiment 3)
FIG. 6 is a perspective view showing a schematic configuration of Embodiment 3 of the present invention. The circuit configuration may be the same as in FIG. Also in this embodiment, the DC power supply unit 14, which is a housing that houses the AC-DC converter 4, and the luminaire main body 31 including the LED mounting substrate 3 are configured separately. In the present embodiment, in order to facilitate inspection, the DC power supply unit 14 is built in the power supply box 16, and a plurality of lead wires 6 are wired from there to each lighting fixture body 31. 7 is a ceiling surface, and 18 is a wall surface.

  Also in this embodiment, if the lead wire 6 is connected to the DC power supply unit 14 after completing the wiring to the luminaire main body 31 first, it is not necessary to consider the polarity at the time of wiring. Wiring work can be done.

  FIG. 7 shows a mounting form of a circular LED mounting substrate 3 adapted to a circular instrument shape. In this example, the rectifying element DB1 and the power input unit 1 (input terminals 1a and 1b in FIG. 1) are arranged near the center of the LED mounting board 3. By adopting such a mounting form and disposing the light diffusing plate on the front surface of the LED mounting substrate 3, the rectifying element DB1 receives light from all directions by the surrounding LEDs, so that the rectifying element DB1 is not easily shaded. Has the effect.

  Alternatively, the LED mounting board may be a double-sided mounting type printed board, the LED may be mounted on the front surface, the rectifying element may be mounted on the back surface, and both may be connected by a through hole of the printed board. In this case, the LEDs can be arranged also on the mounting portion of the rectifying element DB1 in FIG. The same applies to the configuration of FIG.

It is a circuit diagram which shows the circuit structure of Embodiment 1 of this invention. It is sectional drawing which shows the mounting structure of Embodiment 1 of this invention. It is a front view which shows the principal part structure of Embodiment 1 of this invention. It is a perspective view which shows schematic structure of Embodiment 2 of this invention. It is a front view which shows the principal part structure of Embodiment 2 of this invention. It is a perspective view which shows schematic structure of Embodiment 3 of this invention. It is a front view which shows the principal part structure of Embodiment 3 of this invention. It is a schematic block diagram of the conventional LED lighting fixture.

Explanation of symbols

1a, 1b input terminal 2a-2h LED
3 First printed circuit board (LED mounting board)
DB1 Rectifying element 4 AC-DC converter 5 Second printed circuit board 6a, 6b Lead wire

Claims (6)

An LED lighting apparatus comprising: an input terminal to which a DC voltage is applied; at least one light emitting diode; and a first printed circuit board on which the input terminal and the light emitting diode are mounted. An LED lighting apparatus, wherein a rectifying element connected to rectify from an anode to a cathode is mounted on the first printed board. 2. The LED illumination according to claim 1, wherein the rectifying element is connected so as to rectify from the anode of the light emitting diode to the cathode even if the polarity of the DC voltage applied to the input terminal changes. Instruments. 3. The LED lighting apparatus according to claim 1, wherein the rectifying element is a diode bridge part in which a plurality of rectifying diodes are housed in one package. The DC voltage applied to the input terminal is an output voltage of an AC-DC converter that converts commercial AC power into a DC voltage, and the electronic components of the AC-DC converter are mounted on a second printed circuit board. The LED lighting apparatus according to claim 1, wherein the first printed circuit board and the second printed circuit board are connected by a conductive material. 5. The LED lighting apparatus according to claim 4, wherein the first printed circuit board and the second printed circuit board are housed in the same apparatus housing. The LED luminaire according to any one of claims 1 to 5, wherein the rectifying element is disposed at a substantially central portion of a region where the light emitting diode is mounted on the first printed circuit board.

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