JP2013196758A - Led lighting device and illuminating fixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED lighting device capable of detecting arcs with certainty, and protecting a light source part with certainty.SOLUTION: A DC power supply device 22 has a pair of output lines 38 and 39. A light source part 16 has a pair of power lines 35 and 36 connected to the pair of output lines 38 and 39 of the DC power supply device 22 while being substantially short-circuited. The light source part 16 has a light-emitting diode D electrically connected between the power lines 35 and 36, and emitting light by a DC current outputted from the DC power supply device 22. A detection circuit 23 has a detection line 45 electrically connected to the power line 35 of the light source part 16, and detects arcs on the basis of a potential difference between the output line 38 and the power line 35, and a predetermined reference potential. A protection circuit 24 reduces or stops an output of the DC power supply device 22 when the detection circuit 23 detects arcs.

Description

  Embodiments described herein relate generally to an LED lighting device having a light emitting diode that is lit by a direct current output from a direct current power supply device, and a lighting fixture including the LED lighting device.

  Conventionally, for example, in an LED lighting device including a light source unit in which a plurality of light emitting diodes (LEDs) are connected in series, the light emitting diodes are turned on by supplying a direct current from the direct current power supply device to the light emitting diodes.

  In such an LED lighting device, since a DC power supply device is used, it is difficult to extinguish an arc caused by poor connection or disconnection. For this reason, the voltage of the DC power supply device is monitored, the arc is detected by the increase in the voltage of the DC power supply device caused by the occurrence of the arc, and the output from the DC power supply device is reduced when the arc is detected. A protection circuit for performing the protection operation is used.

JP 2010-118270 A

  However, while the arc discharge voltage in the air is about 13V to 20V, in recent years, the number of light emitting diodes used in the light source unit has increased, and the output voltage from the DC power supply unit to the light source unit is relatively high. It's getting bigger. For this reason, even if an arc occurs, the rate of increase in voltage on the DC power supply device side is relatively small, so that it is not easy to detect the arc based on the voltage on the DC power supply device side.

  Problem to be solved by the invention is providing the LED lighting device which can detect an arc reliably, and can protect a light source part reliably, and a lighting fixture provided with the same.

  The LED lighting device according to the embodiment includes a direct-current power supply device, a light source unit separate from the direct-current power supply device, a detection circuit, and a protection circuit. The DC power supply device includes a pair of output lines. The light source unit includes a pair of power supply lines that are substantially short-circuited to the pair of output lines of the DC power supply device. Further, the light source unit includes at least one light emitting diode that is electrically connected between the power supply lines and is lit by a direct current output from the direct current power supply device. The detection circuit includes a detection line that is electrically connected to any one of the power supply lines of the light source unit, and detects an arc based on a potential difference between the output line and the power supply line and a predetermined reference potential. And a protection circuit will reduce or stop the output of a DC power unit, if an arc is detected by a detection circuit.

  According to the present invention, the detection circuit for detecting an arc includes a detection line electrically connected to one of the power supply lines of the light source unit, and is connected to the power supply line by being substantially short-circuited. By detecting an arc based on the potential difference from the output line of the device and a predetermined reference potential, it is expected to detect the occurrence of an arc when a connection failure occurs, and protection is also provided when an arc is detected. It can be expected that the light source unit and the like are reliably protected by reducing or stopping the output of the DC power supply device by the circuit.

It is a circuit diagram which shows the LED lighting device of 1st Embodiment. It is a perspective view of the lighting fixture provided with the LED lighting device same as the above. It is a circuit diagram which shows the LED lighting device of 2nd Embodiment. It is a circuit diagram which shows the LED lighting device of 3rd Embodiment.

  Hereinafter, the configuration of the first embodiment will be described with reference to FIGS. 1 and 2.

  In FIG. 2, 11 is a lighting fixture, and this lighting fixture 11 is a downlight embedded in a ceiling surface etc., for example. In the lighting fixture 11, a circular decorative frame 13 is provided on the lower end side of the substantially cylindrical appliance main body 12, and a translucent cover 14 is disposed on the decorative frame 13. The appliance main body 12 includes an attachment spring 15 for fixing the appliance main body 12 to an attachment surface such as a ceiling.

  In addition, the instrument main body 12 has a light source unit 16 that is a lamp body and a reflector (not shown) disposed inside the lower end side. In addition, a first connection portion 17 as one connector which is a terminal block electrically connected to the light source portion 16 is provided on the upper portion of the instrument main body 12, and the first connection portion 17 is Via a second connection portion 18 as the other connector, the power supply cable 19 and the light source portion 16 which are wiring portions are electrically and mechanically connected to a power supply unit 20 which is a separate power supply device.

  As shown in FIG. 1, the power supply unit 20 includes a DC power supply device 22 electrically and mechanically connected to the power cable 19, a detection circuit 23 for detecting an arc, and a protection circuit 24. The power supply unit 20 constitutes an LED lighting device 25 together with the light source unit 16.

  Here, the first connection portion 17 is provided with three terminals 17a, 17b, and 17c, and the second connection portion 18 is provided with three terminals 18a, 18b, and 18c. The terminals 17a, 17b, and 17c and the terminals 18a, 18b, and 18c are electrically and mechanically connected to each other in a state where the first connecting portion 17 and the second connecting portion 18 are connected.

  The light source unit 16 includes a pair of high-voltage and low-voltage power lines 35 and 36, and at least one light-emitting diode (LED in this embodiment) connected in series in the present embodiment. ) D. The power lines 35 and 36 are electrically and mechanically connected to the terminals 17a and 17b of the first connecting portion 17.

  The DC power supply 22 is, for example, a power supply obtained by rectifying a (commercial) AC power supply. The DC power supply 22 has a pair of high-voltage side and low-voltage side output lines 38 and 39 that output a DC power source for causing the light-emitting diode D of the light source unit 16 to emit light. These output lines 38 and 39 constitute the power cable 19 and are electrically and mechanically connected to the terminals 18a and 18b of the second connecting portion 18. That is, the pair of output lines 38 and 39 of the DC power supply device 22 and the pair of power supply lines 35 and 36 of the light source unit 16 are electrically and mechanically connected via the first and second connection parts 17 and 18. Has been. For this reason, the pair of output lines 38 and 39 of the DC power supply device 22 and the pair of power supply lines 35 and 36 of the light source unit 16 are connected in a state of being substantially short-circuited. And a pair of power wires 35 and 36 constitute main electric wires 41 and 42. In addition, the state which short-circuits substantially means that the impedance (voltage drop in the main electric wires 41 and 42) of the main electric wires 41 and 42 is 0 or a small value very close to 0 (substantially 0). .

  The detection circuit 23 also has a Zener diode ZD as a reference potential setting means for setting a reference potential (equivalent to a Zener voltage) having a predetermined voltage value of, for example, 20 V or less, a resistor R1 as a current limiting element, and a control element. A photocoupler PC, a capacitor C as a protection element, and a detection line 45 are included. A resistor R1 is electrically connected to the output line 38, and a series circuit of a Zener diode ZD and a light-emitting element PCD (for example, an infrared light-emitting diode) of a photocoupler PC is connected to the resistor R1, a capacitor C is electrically connected in parallel, and the light-emitting element PCD of the photocoupler PC is electrically and mechanically connected to the terminal 18c of the second connecting portion 18.

  Further, the light receiving element PCQ of the photocoupler PC is electrically connected to the output line 39. A protection circuit 24 is electrically connected to the light receiving element PCQ (for example, a phototransistor) of the photocoupler PC. The protection circuit 24 is electrically connected to the DC power supply device 22, and the output of the DC power supply device 22 can be variably controlled.

  Further, both ends of the detection line 45 are electrically and mechanically connected to the terminal 17c of the first connection portion 17 and the power supply line 35. Therefore, the detection line 45 is electrically connected to the light emitting element PCD and the capacitor C of the photocoupler PC via the terminal 17c of the first connection portion 17 and the terminal 18c of the second connection portion 18. .

  Next, the operation of the first embodiment will be described.

  In the state in which the connection parts 17 and 18 are normally connected, the main electric wires 41 and 42 are substantially short-circuited, so that a potential difference equal to or higher than the reference potential set by the Zener diode ZD is generated on the output line 38 side and the power supply line. Since it does not occur with the side of 35 (substantially no potential difference), the detection circuit 23 and the protection circuit 24 do not operate. Therefore, DC power (constant current) output from the output lines 38 and 39 of the DC power supply device 22 is supplied to the light emitting diodes D of the light source unit 16 via the power lines 35 and 36, and these light emitting diodes D emit light.

  On the other hand, for example, when a connection failure (contact failure) occurs at a position such as the second connection portion 18 and an arc is generated, a potential difference is generated between the output line 38 side and the power supply line 35 side of the main wire 41. . This potential difference is about 13 V to 20 V, which is a general arc discharge voltage in the air, and is larger than the reference potential set by the Zener diode ZD. Therefore, when the Zener diode ZD and the light emitting device PCD of the photocoupler PC are turned on, an arc is detected in the detection circuit 23, and the current limited by the resistor R1 is supplied to the light emitting device PCD of the photocoupler PC. The light emitting element PCD of the photocoupler PC emits infrared light. Therefore, the light receiving element PCQ of the photocoupler PC is turned on by receiving the infrared emission from the light emitting element PCD, and the power is supplied to the protection circuit 24. The protection circuit 24 outputs the output from the DC power supply device 22. The generated arc is extinguished by lowering (including stopping).

  As described above, according to the first embodiment, the detection circuit 23 for detecting the arc includes the detection line 45 electrically connected to the power supply line 35 of the light source unit 16. By detecting the arc based on the potential difference between the output line 38 of the DC power supply device 22 connected in a short circuit and the predetermined reference potential, the occurrence of an arc when the connection failure occurs in the main electric wire 41 is ensured. When the arc is detected, the output of the DC power supply 22 is lowered by the protection circuit 24, so that the light source unit 16 and the like can be reliably protected.

  Further, by setting the reference potential to be compared with the potential difference between the output line 38 of the DC power supply device 22 connected in a short circuit with the power supply line 35 in the detection circuit 23 to a predetermined potential of 20 V or less, It is possible to reliably detect a potential difference caused by an arc that is about 13 V to 20 V, which is a discharge voltage of the arc in the air.

  And by providing said LED lighting device 25 in the lighting fixture 11, generation | occurrence | production of an arc can be prevented reliably and it can improve reliability, and since a special connection etc. are not required, an inexpensive protection system can be provided. .

  Next, a second embodiment will be described with reference to FIG. In addition, about the structure similar to the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  The second embodiment includes a resistor R2, which is a load that electrically connects the detection circuit 23 and the protection circuit 24 side of the first embodiment. Specifically, the resistor R2 electrically connects a series circuit of the Zener diode ZD and the photocoupler PC and a parallel circuit of the capacitor C and the output line 39. Therefore, the resistor R2 electrically connects the detection line 45 and the protection circuit 24 side.

  And in this structure, when each connection part 17 and 18 is normally connected, and when a connection failure (contact failure) occurs at a position such as the second connection part 18, an arc is generated. The operation is the same as in the first embodiment.

  Even if the connection of the detection line 45 (for example, connection to the power supply line 35 or connection of the terminals 17c and 18c) is disconnected, the series circuit of the Zener diode ZD and the photocoupler PC and the capacitor C are not connected. The parallel circuit is not opened, and is connected to the output line 39 via the resistor R2 to complete the circuit. Therefore, when the arc is generated, the Zener diode ZD and the light emitting element PCD of the photocoupler PC are turned on, and the current limited by the resistor R1 is supplied to the light emitting element PCD of the photocoupler PC. The light emitting element PCD emits infrared light, and the light receiving element PCQ of the photocoupler PC receives the infrared light emitted from the light emitting element PCD, so that the power is supplied to the protection circuit 24. The generated arc is extinguished by reducing the output from 22 (including stopping).

  As described above, according to the second embodiment, even when the detection line 45 is temporarily disconnected by electrically connecting the detection line 45 of the detection circuit 23 and the protection circuit 24 side by the resistor R2, The protection operation can be performed by operating the photocoupler PC of the detection circuit 23 and operating the protection circuit 24.

  In each of the above embodiments, the detection circuit 23 may compare the potential difference and the reference potential between the output line 38 side and the power supply line 35 side of the main electric wire 41 using, for example, a comparator.

  Next, a third embodiment will be described with reference to FIG. In addition, about the structure similar to said each embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the third embodiment, a control circuit 48 functioning as a detection circuit and a protection circuit is provided in place of the detection circuit 23 and the protection circuit 24 in the above embodiments.

  The control circuit 48 is, for example, a microcomputer or the like, and is electrically connected to the terminal 18c of the second connection unit 18 and the output line 39 of the DC power supply device 22. Further, both ends of the detection line 45 are electrically and mechanically connected to the terminal 17c of the first connection portion 17 and the power supply line 36.

  Furthermore, the control circuit 48 can variably set the output of the DC power supply device 22 and detects an arc based on a potential difference between the output line 39 side and the power supply line 36 side of the main wire 42 and a predetermined reference potential. When an arc is detected, the output of the DC power supply 22 is reduced (including stopping). Here, the control circuit 48 stores a reference potential having a predetermined voltage value of, for example, 20 V or less, and when the length of the main electric wires 41, 42 is increased, for example, A voltage drop occurs between the output line 39 of the main electric wire 42 and the power supply line 36 in a state where the pair of output lines 38 and 39 and the pair of power supply lines 35 and 36 of the light source unit 16 are normally connected. In this case, the stored reference potential is offset (added) by the voltage drop. For example, when the voltage drop is known in advance, this offset may be added to the reference potential in advance, and the pair of output lines 38 and 39 and the pair of power supply lines 35 and 36 are normal. The line voltage of the main electric wire 42 in the connected state may be stored (actually measured), and the reference potential may be varied according to this.

  And in the state where each connection part 17 and 18 is normally connected, since the main electric wires 41 and 42 are substantially short-circuited and connected, the potential difference greater than the reference potential is the output line 39 side and the power supply line 36 side. The control circuit 48 does not reduce the output of the DC power supply 22 and the DC output from the output lines 38 and 39 of the DC power supply 22 is not generated. A power source (constant current) is supplied to the light emitting diodes D of the light source unit 16 through the power supply lines 35 and 36, and these light emitting diodes D emit light.

  On the other hand, for example, when an arc is generated due to a connection failure (contact failure) at the position of the second connection portion 18 or the like, 13V to 20V is provided between the output line 39 side and the power supply line 36 side of the main electric wire 42. A potential difference of a degree occurs. Note that this potential difference increases in the main electric wire 42 when the voltage drop occurs between the output line 39 and the power supply line 36. The reference potential offset by the drop is compared with this potential difference, and an arc is detected when the potential difference becomes larger than the reference potential. When the arc is detected, the control circuit 48 reduces the output from the DC power supply device 22 (including the stop), thereby extinguishing the generated arc.

  As described above, according to the third embodiment, the control circuit 48 for detecting an arc includes the detection line 45 electrically connected to the power supply line 36 of the light source unit 16, and substantially includes the power supply line 36. By detecting the arc based on the potential difference with the output line 39 of the DC power supply device 22 connected in a short circuit and a predetermined reference potential, the occurrence of an arc is reliably ensured when a connection failure occurs in the main wire 42. When the arc is detected, the control circuit 48 reduces the output of the DC power supply 22 to reliably protect the light source unit 16 and the like.

  Further, by setting the reference potential to be compared with the potential difference between the output line 39 of the DC power supply device 22 connected to the power supply line 36 in a short circuit in the control circuit 48 to a predetermined potential of 20V or less, It is possible to reliably detect a potential difference caused by an arc that is about 13 V to 20 V, which is a discharge voltage of the arc in the air.

  In addition, the control circuit 48 includes a pair of output lines 38 and 39 of the DC power supply 22 and a pair of power lines 35 and 36 of the light source unit 16 even when the main wires 41 and 42 are long and a voltage drop occurs, for example. By offsetting the reference potential by the voltage drop that occurs between the output line 39 and the power supply line 36 of the main electric wire 42 in a state where the main wire 42 is normally connected, the voltage drop that occurs in the main electric wire 42 causes an arc It can prevent reliably that detection accuracy falls.

  And although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

11 Lighting equipment
12 Instrument body
16 Light source
22 DC power supply
23 Detection circuit
24 Protection circuit
25 LED lighting device
35, 36 Power line
38, 39 output line
45 Detection line
48 Control circuit that functions as a detection circuit and protection circuit D Light-emitting diode
R2 load resistance

Claims (5)

A DC power supply device having a pair of output lines for outputting DC current;
A pair of power supply lines that are substantially short-circuited to the pair of output lines of the DC power supply device, and at least one that is lit by a DC current that is electrically connected between the power supply lines and output from the DC power supply device A light source unit that is separate from the DC power supply device, comprising one light emitting diode;
A detection circuit that includes a detection line that is electrically connected to any one of the power supply lines of the light source section, and that detects an arc based on a potential difference between the output line side and the power supply line side and a predetermined reference potential;
A protection circuit that reduces or stops the output of the DC power supply when an arc is detected by the detection circuit;
The LED lighting device characterized by comprising. The LED lighting device according to claim 1, further comprising a load that electrically connects the detection line of the detection circuit and the protection circuit side. The detection circuit offsets a predetermined reference potential by a voltage drop that occurs between the output line and the power supply line when the pair of output lines of the DC power supply unit and the pair of power supply lines of the light source unit are normally connected. The LED lighting device according to claim 1 or 2, wherein: The LED lighting device according to any one of claims 1 to 3, wherein the predetermined reference potential of the detection circuit is set to a predetermined voltage of 20 V or less. An LED lighting device according to any one of claims 1 to 4;
An instrument body in which at least a light source part of the LED lighting device is disposed;
The lighting fixture characterized by comprising.

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