JP2008278641A - Power supply unit and illuminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply unit to reduce power consumption while ensuring safety, and to provide an illuminator. <P>SOLUTION: While a light-emitting diode 26 is attached removably to a light source fixing section 22, a smoothing capacitor 24 is charged through the light-emitting diode 26, a control circuit 25 is started when the charging voltage of the smoothing capacitor 24 reaches a predetermined level to turn on/off a switching transistor 14 and to switch a switching transistor 13. Under a state where the light-emitting diode 26 is removed from the light source fixing section 22, a charging way to the smoothing capacitor 24 is opened to block the operation of the control circuit 25 and switching drive of the switching transistor 13 is prohibited. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power supply device and a lighting fixture that are optimal for driving a light emitting element such as a light emitting diode.

  Recently, a direct current power supply device using a switching element is often used as a power source for a light emitting element such as a light emitting diode.

In this type of power supply device, for example, as disclosed in Patent Document 1, a light emitting diode driving device in which a light emitting diode is driven by a DC output of a boost chopper provided with an inductance, a switching element, and a diode, As disclosed in Document 2, a DC input voltage is supplied to the primary winding of the switching transformer, excitation energy is accumulated in the primary winding of the switching transformer when the switching element is on, and the switching transformer is turned off when the switching element is off. The excitation energy accumulated in the primary winding is output from the secondary winding, the AC output output from this secondary winding is rectified through a diode, smoothed by a smoothing capacitor, and supplied to the load as a DC output. Such a switching power supply device is known.
JP 2001-313423 A JP 2003-88119 A

  However, those disclosed in Patent Documents 1 and 2 are in a state where a load such as a light emitting diode is not connected, that is, when the load is removed, and when the load is not attached as viewed from the power source side, The DC output is not stopped.

  However, continuing to generate output even when a load is not attached is to consume extra power during that time, which is not desirable under the recent trend of energy saving. In addition, the fact that the output is supplied even though the load is broken is not preferable from the viewpoint of work safety when the user inspects the load failure state.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a power supply device and a lighting fixture that can reduce power consumption and can ensure safety.

  The invention according to claim 1 includes a switching means, a DC output generating means for generating a DC output by a switching operation of the switching means; a control means for controlling the switching operation of the switching means; and the DC output generating means A load to which the generated DC output is supplied; and a starting unit that is connected to a power supply terminal of the control unit and is charged via the load to start the control unit.

  Here, switching transistors such as FETs and bipolar transistors are used as the switching means. Further, the DC output generating means includes a switching transistor, a switching transformer, a rectifying / smoothing circuit, and the like. For the load, a light emitting diode, a laser diode, or the like is used. The term “charged via the load” of the starting means includes charging by a current flowing through the load or a voltage generated at the load.

  According to a second aspect of the present invention, in the first aspect of the present invention, the load can be disconnected from the DC output generating means, and the starting means is connected to the DC output generating means. Charging is performed through the load.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the load is composed of one or more light emitting diodes, and the starting means is generated between a current flowing through the light emitting diodes or between the light emitting diodes. It is characterized by being charged by voltage.

  The invention according to claim 4 is a lighting fixture to which the power supply device according to any one of claims 1 to 3 is applied.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to reduce power consumption, the power supply device and lighting fixture which can ensure safety | security can be provided.

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

(First embodiment)
First, the lighting fixture to which the power supply device of the present invention is applied will be briefly described. 1 and 2, reference numeral 1 denotes an instrument body, and the instrument body 1 is made of aluminum die-casting and has a cylindrical shape with both ends opened. The appliance body 1 is internally divided into three in the vertical direction by partition members 1 a and 1 b, and a space between the lower opening and the partition member 1 a is formed in the light source unit 2. The light source unit 2 is provided with a plurality of LEDs 2a and a reflector 2b. The plurality of LEDs 2a are arranged and mounted at equal intervals along the circumferential direction of a disk-shaped wiring board 2c provided on the lower surface of the partition member 1a.

  A space between the partition members 1 a and 1 b of the instrument body 1 is formed in the power supply chamber 3. In the power supply chamber 3, a wiring board 3a is disposed on the partition member 1a. The wiring board 3a is provided with each electronic component constituting the power supply device of the present invention for driving the plurality of LEDs 2a. The DC power supply device and the plurality of LEDs 2 a are connected by lead wires 4.

  A space between the partition plate 1 b of the instrument body 1 and the upper opening is formed in the power supply terminal chamber 5. In the power terminal room 5, a power terminal block 6 is provided on the partition plate 1b. This power supply terminal block 6 is a terminal block for supplying AC power of commercial power to the power supply device in the power supply chamber 3, and serves as a power cable terminal portion on both sides of the box 6a made of electrically insulating synthetic resin. It has an insertion port 6b, an insertion port 6c serving as a feed cable terminal, a release button 6d for separating the power line and the feed line, and the like.

  FIG. 3 shows a schematic configuration of the power supply device of the present invention incorporated in the power supply chamber 3 of the lighting fixture configured as described above.

  In FIG. 3, reference numeral 11 denotes a DC power source. The DC power source 11 generates, for example, a full-wave rectified AC output from an AC power source (commercial power source) and smoothes the full-wave rectified output by a smoothing capacitor to generate a DC output. What to do is used.

  A ripple current smoothing capacitor 12 is connected to both ends of the DC power supply 11, and a primary circuit 13a of a switching transformer 13 and a series circuit of a switching transistor 14 as switching means are connected. The switching transformer 13 includes a secondary winding 13b and an auxiliary winding 13c that are magnetically coupled to the primary winding 13a.

  A snubber circuit 171 composed of a parallel circuit of a capacitor 15 and a resistor 16 and a series-parallel circuit of a diode 17 of the illustrated polarity is connected to both ends of the primary winding 13a of the switching transformer 13. This snubber circuit 171 absorbs the flyback voltage generated in the primary winding 13 a of the switching transformer 13 by charging by the capacitor 15 and discharging of the resistor 16, and absorbs the ringing voltage generated by the leakage inductance of the switching transformer 13 by the capacitor 15. To do.

  The secondary winding 13b of the switching transformer 13 is connected to a rectifying / smoothing circuit 20 including a diode 18 having a polarity shown and a smoothing capacitor 19. The rectifying / smoothing circuit 20 constitutes a DC output generating means together with the switching transistor 14 and the switching transformer 13, rectifies the AC output generated from the secondary winding 13b of the switching transformer 13 by the diode 18, and the rectified output is smoothed by the smoothing capacitor. 19 is smoothed and generated as a DC output.

  A connection point between the diode 18 and the smoothing capacitor 19 of the rectifying and smoothing circuit 20 is connected to a connection point between the parallel circuit of the capacitor 15 and the resistor 16 and the primary winding 13a through the resistor 21.

  Connection terminals 21 a and 21 b are connected to both ends of the smoothing capacitor 19 of the rectifying and smoothing circuit 20. These connection terminals 21a and 21b will be described later.

  On the other hand, a series circuit of a diode 23 and a smoothing capacitor 24 in the illustrated polarity direction is connected to both ends of the auxiliary winding 13 c of the switching transformer 13. The smoothing capacitor 24 is charged by a current flowing in a light emitting diode 26, which will be described later, and constitutes a starting means for starting the control circuit 25. When an AC output is generated from the auxiliary winding 13c, the smoothing capacitor 24 rectifies the AC output. And is supplied with the driving power to the control circuit 25.

  Both ends of the smoothing capacitor 24 are connected to power terminals 25a and 25b of a control circuit 25 as a control means. In the control circuit 25, the drive terminal 25 c is connected to the gate of the switching transistor 14 through the resistor 29. The control circuit 25 is activated by the charging voltage of the smoothing capacitor 24 at the start of driving, and the switching transistor 14 is switched on and off by the operation thereof to drive the switching transformer 13.

  A connection terminal 21 c is connected to a connection point between the diode 23 and the smoothing capacitor 24 via a resistor 28.

  A light emitting diode 26 (corresponding to the LED 2a described in FIG. 2) as a load is connected to the connection terminals 21a, 21b, and 21c. In this case, the light emitting diode 26 has the connection terminal 27a connected to the anode and the connection terminals 27b and 27c connected to the cathode, respectively. The light emitting diode 26 is unitized together with the connection terminals 27a, 27b, and 27c, and can be connected to or disconnected from the connection terminals 21a, 21b, and 21c via the connection terminals 27a, 27b, and 27c. For example, the connection terminals 21a, 21b, and 21c are provided in the light source mounting portion 22 as load mounting means, and by attaching the unitized light emitting diode 26 to the light source mounting portion 22, the connection terminals 27a, 27b, 27c is electrically connected to the connection terminals 21a, 21b, and 21c.

  Next, the operation of the embodiment configured as described above will be described.

  First, when the light emitting diode 26 is mounted on the light source mounting portion 22 and the connection terminals 27a, 27b, and 27c are electrically connected to the connection terminals 21a, 21b, and 21c (FIG. 3 shows this state). Will be explained. In this case, when a power switch (not shown) is turned on, the current of the DC power supply 11 flows through the resistor 21 to the light emitting diode 26, and further flows through the resistor 28 to the smoothing capacitor 24 to charge the smoothing capacitor 24. .

  When the charging voltage of the smoothing capacitor 24 reaches a predetermined value, the control circuit 25 is activated by this charging voltage, and the switching transistor 14 is turned on / off. When the switching transistor 14 is turned on / off, the switching transformer 13 is switched.

  In this case, when the switching transistor 14 is turned on, current is supplied from the DC power source 11 to the primary winding 13a of the switching transformer 13 to store energy, and when the switching transistor 14 is turned off, energy stored in the primary winding 13a is stored in the secondary winding. Release through 13b. As a result, a direct current output is generated via the rectifying and smoothing circuit 20, and the light emitting diode 26 is turned on.

  On the other hand, when the switching transformer 13 starts switching driving, an AC output is generated in the auxiliary winding 13c. The AC output is rectified by the diode 23, and the rectified output is charged in the smoothing capacitor 24. Therefore, thereafter, the control circuit 25 is driven by the charging voltage of the smoothing capacitor 24 charged by the rectified output of the diode 23, and turns on and off the switching transistor 14.

  Next, the case where the light emitting diode 26 is removed from the light source mounting portion 22 and the connection terminals 27a, 27b, and 27c are disconnected from the connection terminals 21a, 21b, and 21c will be described. In this case, when a power switch (not shown) is turned on, the connection terminals 27a, 27b, and 27c are not connected to the connection terminals 21a, 21b, and 21c. 24 is never charged. For this reason, the charging voltage of the smoothing capacitor 24 remains unchanged, and the control circuit 25 using this charging voltage as the power source at the start of driving does not operate. As a result, the switching transistor 14 remains off and the switching transformer 13 is not switched. That is, the switching drive of the switching transformer 13 can be stopped in the load non-mounted state in which the light emitting diode 26 is detached from the light source mounting portion 22.

  Therefore, in this way, the light emitting diode 26 is detachably provided on the light source mounting portion 22, and the smoothing capacitor 24 is charged via the light emitting diode 26 with the light emitting diode 26 mounted on the light source mounting portion 22. When the charging voltage of the smoothing capacitor 24 reaches a predetermined value, the control circuit 25 is activated, the switching transistor 14 is turned on / off, the switching transformer 13 can be switched, and the light emitting diode 26 is removed from the light source mounting portion 22. Then, the charging path of the smoothing capacitor 24 is cut off, the operation of the control circuit 25 is blocked, and the switching drive of the switching transformer 13 is prohibited. As a result, when the light emitting diode 26 is removed and the load is not mounted as viewed from the power supply side, the generation of DC output by the switching drive of the switching transformer 13 can be stopped, so that the output is performed even when the conventional load is not mounted. Compared to those that continue to generate power, the power consumption can be greatly reduced, which can greatly contribute to energy saving. Further, even when the load breaks down and the load is not attached, the switching drive of the switching transformer 13 can be stopped so that no output is generated, so that the user can inspect the load failure state. It is also possible to ensure safety.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.

  FIG. 4 shows a schematic configuration of the second embodiment, and the same parts as those in FIG. In this case, the negative electrode end of the DC power supply 11 is connected to a connection point between the secondary winding 13 b of the switching transformer 13 and the smoothing capacitor 19 of the rectifying and smoothing circuit 20. Further, a plurality of (four in the illustrated example) light-emitting diodes 31 to 34 connected in series are used as loads.

  The connection terminal 35 a is connected to the anode of the light emitting diode 31, and the connection terminal 35 b is connected to the cathode of the light emitting diode 34. A connection terminal 35 c is connected to a connection point between the light emitting diode 32 and the light emitting diode 33. Also in this case, the light emitting diodes 31 to 34 are unitized together with the connection terminals 35 a, 35 b, and 35 c, and by attaching the unitized light emitting diodes 31 to 34 in the light source mounting portion 22, the connection terminal 35 a , 35b, 35c are electrically connected to the connection terminals 21a, 21b, 21c.

  Others are the same as FIG.

  In this case, when the light emitting diodes 31 to 34 are mounted on the light source mounting portion 22 and the connection terminals 35a, 35b, and 35c are electrically connected to the connection terminals 21a, 21b, and 21c (FIG. 4 shows this state). The voltage generated across the series circuit of the light emitting diodes 33 and 34 is applied across the smoothing capacitor 24. Thereby, the smoothing capacitor 24 is charged, and when the charging voltage reaches a predetermined value, the control circuit 25 is activated, the switching transformer 13 is driven to be switched on, and the light emitting diodes 31 to 34 are turned on.

  On the other hand, when the light emitting diodes 31 to 34 are removed from the light source mounting portion 22 and the connection terminals 35a, 35b, and 35c are disconnected from the connection terminals 21a, 21b, and 21c, they occur at both ends of the series circuit of the light emitting diodes 33 and 34. The voltage was cut off and the smoothing capacitor 24 was not charged. As a result, the charging voltage of the smoothing capacitor 24 does not increase, the control circuit 25 does not start, the switching transistor 14 remains off, and the switching transformer 13 is not switched.

  Therefore, even in this case, the same effect as that of the first embodiment can be obtained.

(Third embodiment)
Next, a third embodiment of the present invention will be described.

  FIG. 5 shows a schematic configuration of the third embodiment, and the same parts as those in FIG. In this case, the connection terminal 21b is connected to the connection point of the diode 23 and the smoothing capacitor 24 via the resistor 28, and the connection terminal 21c is connected to the parallel circuit of the capacitor 15 and the resistor 16 and the primary winding 13a via the resistor 21. Connected to a point.

  Further, a plurality of (five in the illustrated example) light emitting diodes 41 to 45 connected in series are used as loads. The connection terminal 46 a is connected to the anode of the light emitting diode 41, and the connection terminal 46 b is connected to the cathode of the light emitting diode 45. A connection terminal 46 c is connected to a connection point between the light emitting diode 43 and the light emitting diode 44. Also in this case, the light emitting diodes 41 to 45 are unitized together with the connection terminals 46 a, 46 b, 46 c, and by attaching the unitized light emitting diodes 41 to 45 in the light source mounting portion 22, the connection terminal 46 a , 46b, 46c are electrically connected to the connection terminals 21a, 21b, 21c.

  Others are the same as FIG.

  Even in this case, when the light emitting diodes 41 to 45 are mounted on the light source mounting portion 22 and the connection terminals 46a, 46b, and 46c are electrically connected to the connection terminals 21a, 21b, and 21c (FIG. 5 illustrates this state). The current from the DC power supply 11 flows to the light emitting diodes 44 and 45 through the resistor 21, and further flows to the smoothing capacitor 24 through the resistor 28, so that the smoothing capacitor 24 is charged. Thereby, the smoothing capacitor 24 is charged, and when this charging voltage reaches a predetermined value, the control circuit 25 is activated, the switching transformer 13 is driven to be switched on, and the light emitting diodes 41 to 45 are turned on.

  On the other hand, when the light emitting diodes 41 to 45 are removed from the light source mounting portion 22 and the connection terminals 46a, 46b, and 46c are disconnected from the connection terminals 21a, 21b, and 21c, the current flowing from the DC power supply 11 to the smoothing capacitor 24 is interrupted. Therefore, the smoothing capacitor 24 is not charged. As a result, the charging voltage of the smoothing capacitor 24 does not increase, the control circuit 25 does not operate, the switching transistor 14 remains off, and the switching transformer 13 is not switched.

  Therefore, even in this case, the same effect as that of the first embodiment can be obtained.

  In addition, this invention is not limited to the said embodiment, In the implementation stage, it can change variously in the range which does not change the summary. For example, in the above-described embodiment, the smoothing capacitor 24 charged by the output of the auxiliary winding 13c of the switching transformer 13 is used as a starting power supply at the time of startup of the control circuit 25. A capacitor as a starting power supply may be provided separately from the smoothing capacitor 24. In the above description, the example of the light emitting diode is described as the load.

  Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and is described in the column of the effect of the invention. If the above effect is obtained, a configuration from which this configuration requirement is deleted can be extracted as an invention.

The perspective view which shows the lighting fixture with which the power supply device concerning the 1st Embodiment of this invention is applied. Sectional drawing of the lighting fixture to which the power supply device concerning 1st Embodiment is applied. The figure which shows schematic structure of the power supply device concerning 1st Embodiment. The figure which shows schematic structure of the power supply device concerning the 2nd Embodiment of this invention. The figure which shows schematic structure of the power supply device concerning the 3rd Embodiment of this invention.

Explanation of symbols

1 ... The instrument body,
DESCRIPTION OF SYMBOLS 2 ... Light source part, 2a ... LED, 4 ... Lead wire 5 ... Power supply terminal chamber, 6 ... Power supply terminal block 11 ... DC power supply, 13 ... Switching transformer,
14 ... switching transistor, 171 ... snubber circuit,
DESCRIPTION OF SYMBOLS 20 ... Rectification smoothing circuit, 22 ... Light source attachment part, 25 ... Control circuit 31-34, 41-45 ... Light emitting diode

Claims (4)

DC output generating means that includes switching means and generates a DC output by a switching operation of the switching means;
Control means for controlling the switching operation of the switching means;
A load to which a DC output generated by the DC output generating means is supplied;
An activation means connected to a power supply terminal of the control means and charged via the load to activate the control means;
A power supply device comprising: 2. The load is detachable from the DC output generating means, and the starting means is charged via the load in a connected state of the load to the DC output generating means. The power supply described. The load comprises one or more light emitting diodes,
The power supply apparatus according to claim 1, wherein the activation unit is charged by a current flowing through the light emitting diode or a voltage generated between the light emitting diodes. A lighting fixture to which the power supply device according to any one of claims 1 to 3 is applied.

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