JP5331512B2 - LED lighting equipment - Google Patents

Description

  The present invention relates to an LED lighting apparatus that employs an LED as a light source, and more particularly, to an LED lighting apparatus that includes a white LED that obtains white light by emitting a yellow phosphor with a blue LED.

  Conventionally, various LED lighting fixtures using LEDs as light sources are known (see, for example, Patent Document 1). In recent years, white LEDs that output white light have been known. This type of white LED is often used to obtain white light by mixing the blue LED's emission color and the yellow phosphor's fluorescent color by sealing the blue LED with a resin in which a yellow phosphor is dispersed. It has been.

JP 2007-234558 A

However, depending on the path when the light emitted from the light emitting surface of the blue LED passes through the yellow phosphor, the yellow fluorescent color becomes too strong, and even when mixed with blue, white light cannot be obtained and Become. For this reason, the irradiated light contains yellow light in addition to white light, and when the irradiated light is irradiated, a yellowish spot is generated on the irradiated surface, thereby causing color unevenness and the irradiation object. The color development was poor, and the pattern and characters drawn on the irradiated area were degraded. In order to solve this problem, it is conceivable to separate only yellow light through illumination light through a color separation lens, but there is a problem that the amount of illumination light is reduced.
This invention is made | formed in view of the situation mentioned above, and aims at providing the LED lighting fixture which can suppress irradiation of the light biased to the fluorescence color.

In order to achieve the above-mentioned object, the present invention provides a light source for white LED that encloses a blue LED in a resin in which a phosphor is dispersed and obtains white light by mixing the emission color of the blue LED and the fluorescence color of the phosphor. in the LED lighting device with a, has a concave reflecting surface which the bottom portion is opened, said bottom opening to comprise the reflector white LED is disposed in, the white of the opening of the bottom above said white LED Among the light components radiated from the white LED, a predetermined gap is provided between the LED and the bottom of the reflector so that a light component having a long distance passing through the resin and biased to a fluorescent color component is incident. The light component biased toward the fluorescent color component is emitted from the gap to the outside of the reflector, and the light component without bias is reflected by the reflector .

  According to the present invention, in the above LED lighting apparatus, the white LED is mounted between the LED board on which the blue LED is mounted, the bottom of the concave reflecting surface, and the LED board, and forms the predetermined gap. And the gap forming member has insulating properties and flexibility, and is pressed by the bottom of the concave reflecting surface so that the LED substrate is brought into close contact with the high thermal conductivity member on the appliance body side. .

  According to the present invention, among the light components radiated from the white LED, the light component having a long distance passing through the resin and biased to the fluorescent color component is emitted from the gap to the outside of the reflector. For this reason, since the light biased to the fluorescent color does not enter the concave reflecting surface, the irradiation of the light is suppressed and white light can be mainly emitted.

It is a figure which shows all the front, a plane, a right side, and a back surface of the LED projector which concerns on embodiment of this invention. It is an assembly drawing of a light source case and a light source unit. It is a figure which shows the structure of a LED package. It is a figure which expands and shows an LED package and a reflector. It is a figure which expands and shows the light emission part of a LED package.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, an LED projector is illustrated as an example of an LED lighting fixture, but the present invention is not limited to this, and any LED lighting fixture having a support leg can be applied.

  FIG. 1 is a diagram illustrating both a front surface, a plane surface, a right side surface, and a back surface of an LED projector 1 according to the present embodiment. The LED projector 1 includes a luminaire main body 7 formed by integrally connecting a light source case 3 and a power supply case 5, and a support leg 9 for attaching a structure that supports the luminaire main body 7 at a variable angle. Each of the light source case 3, the power supply case 5, and the support legs 9 is integrally formed from a material having high thermal conductivity such as aluminum die casting.

The light source case 3 is a case for housing a light source unit 33 having a plurality of LED packages 35. The light source case 3 has a substantially box shape with a thickness smaller than the length and width, and a substantially rectangular irradiation opening 13 on the front. An opening and a transparent cover 15 made of glass or resin are fitted, and light is irradiated from the irradiation opening 13 toward the front. The back surface of the light source case 3 swells in a substantially arc shape, and a large number of heat radiation fins 11 extending vertically are integrally formed on this back surface.
At the lower end of the light source case 3, a support leg mounting portion 4 formed integrally with a width B smaller than the width A of the main part of the light source case 3 is integrally formed.

  The power supply case 5 is a horizontally long box-shaped case containing a power supply circuit for supplying power to the LED package 35. The lateral width is slightly smaller than the support leg mounting portion 4 of the light source case 3, and a gap is provided between the support leg 9. Similarly to the light source case 3, a plurality of heat radiation fins 19 extending vertically are also provided integrally on the back surface of the power supply case 5. The power supply case 5 is integrally coupled to the lower end of the support leg mounting portion 4 of the light source case 3, and thereby a luminaire main body 7 is configured.

  The support leg 9 is a member that is formed in a generally U-shape for supporting the luminaire main body 7 on a structure such as a wall surface or a column of a building with a variable angle, and has an open end at the light source case 3. A support member (support shaft) 21 is rotatably supported on the left and right side surfaces of the support leg mounting portion 4. The shaft support member 21 is formed of a material having high thermal conductivity, such as aluminum die casting, like the light source case 3 and the like, and thermally couples the light source case 3 and the support legs 9 well.

Further, the lateral width of the support leg 9 is approximately the same as the lateral width A of the light source case 3, and the design is devised so that the support leg 9 does not protrude laterally with respect to the luminaire main body 7.
At this time, the leg portion 9A of the support leg 9 has a thickness C defined by the difference between the width A and the width B, and by increasing the thickness of the leg portion 9A compared to a conventional LED projector, The heat capacity of the leg 9A is increased. The thickness C of the leg portion 9A is set to such a thickness that the heat generated by the LED package 35 that cannot be radiated by the light source case 3 alone can be conducted and heat can be radiated satisfactorily. Thereby, even if it does not enlarge the lighting fixture main body 7, the heat dissipation of the heat | fever which the LED package 35 emits is improved.

  Further, as described above, since the power supply case 5 is not in contact with the support leg 9, heat is not transferred from the support leg 9 to the power supply case 5, so that extra heat is applied to the power supply circuit of the power supply case 5. Therefore, the power supply circuit housed in the power supply case 5 is prevented from being damaged by heat.

FIG. 2 is an assembly view of the light source case 3 and the light source unit 33.
The light source unit 33 is configured by connecting a plurality of LED packages 35 in series by wirings 34 and bonding them at a predetermined interval on one rectangular ceramic plate 37 made of alumina having high thermal conductivity, for example. The ceramic plate 37 is provided in close contact with the bottom surface 3 </ b> A of the light source case 3. Thus, by arranging each LED package 35 on one ceramic plate 37, uniform cooling can be achieved while achieving insulation.
The light source case 3 is attached with a reflector 41 having a concave reflecting surface 43 corresponding to each LED package 35 so as to press the light source unit 33 from above, and the adhesion between the light source unit 33 and the light source case 3. Has been increased.

Here, since the light source unit 33 is configured by adhering a plurality of LED packages 35 to a single ceramic plate 37 as described above, the adhesion of the ceramic plates 37 varies among the LED packages 35. It is likely to occur. If the variation occurs in this way, the heat dissipation is different, so that the life of the LED package 35 is also different. Therefore, the reflector 41 presses each LED package 35 so that the adhesiveness does not vary.
More specifically, as shown in FIG. 3, the LED package 35 is a light emitting device in which 24 × 3 LEDs 65 are arranged in a grid pattern on an LED substrate 61 in which an insulating layer 61B is provided on the surface of a metal plate 61A. The light emitting unit 63 emits planar light. In the figure, reference numeral 66 denotes an anode electrode formed on the LED substrate 61, and reference numeral 67 denotes a cathode electrode. The LED package 35 has a high output that outputs a luminous flux of about 1100 lm or more, and the light source unit 33 is composed of six LED packages 35.

  On the light source unit 33, the reflector 41 is provided so as to press the light source unit 33 against the bottom surface 3 </ b> A of the light source case 3. The reflector 41 is formed with a concave reflecting surface 43 corresponding to the light emitting portion 63 of each LED package 35 of the light source unit 33. The bottom 43A of the concave reflecting surface 43 has a bottom 43A as shown in FIG. In addition, a cushioning material 71 having flexibility and insulation is disposed. The bottom 43A of each concave reflecting surface 43 presses the LED substrate 61 against the ceramic plate 37 via the buffer material 71, so that each of the LED packages 35 comes into close contact with the ceramic plate 37, and the variation in adhesion is eliminated. It is.

FIG. 5 is an enlarged view showing the light emitting unit 63 of the LED package 35.
As described above, the LED package 35 is configured by mounting a large number of LEDs 65 arranged in a grid on the LED substrate 61. These LEDs 65 are blue LEDs that emit blue light. In addition, these LEDs 65 are sealed with a resin sealing body 95 in which a fluorescent material that emits yellow fluorescence in response to blue light is scattered and a light emitting surface is flattened. And white light is obtained by the mixed color of the blue luminescent color of LED65, and the yellow fluorescent color of fluorescent substance.

At this time, when the balance between the emission color of the LED 65 and the fluorescent color of the phosphor is lost and the fluorescent color component becomes strong, the light obtained by the color mixture is biased to yellow. That is, as shown in FIG. 5, when the light component K1 heading upward from the LED 65 and the light component K2 heading obliquely are compared, when passing through the sealing body 95 between the light components K1 and K2, respectively. In the path lengths L1 and L2, the path length L2 of the light component K2 in the oblique direction is longer. For this reason, in the direction of the light component K2, it shows that the fluorescence by a fluorescent substance becomes strong compared with the direction of the light component K1.
When the angle with respect to the main irradiation direction of the LED 65 is θ, and the threshold angle at which the balance between the emission color of the LED 65 and the fluorescent color of the phosphor is lost and the deviation to the fluorescent color cannot be ignored in the usage of the lamp is θth, the path length Since L becomes longer as the angle θ becomes larger, the light component irradiated in the range of 180 ° ≧ threshold angle θth (hereinafter referred to as “fluorescent color excess range”) is significantly biased to the yellow fluorescent color. When such light is irradiated, the irradiated object will be yellowish outside the irradiation range.

  Therefore, in the present embodiment, as shown in FIG. 4, the bottom 43A of the concave reflecting surface 43 of the reflector 41 is disposed above the LED package 35 above the range in which the light component in the fluorescent color excess range passes. . For this reason, the light component in the fluorescent color excess range is emitted to the outside of the reflector 41 from the gap between the bottom portion 43A of the reflector 41 and the LED package 35 and enters the concave reflecting surface 43, that is, white light. Is irradiated as irradiation light by the reflector 41.

  A gap between the bottom 43A of the reflector 41 and the LED package 35 is formed by the buffer material (gap forming member) 71, and the size of the gap is adjusted by the thickness, flexibility, and the like. The cushioning material 71 is made of a material having high transparency to yellow light (for example, silicon rubber), which prevents yellow light from being reflected by the cushioning material 71 and entering the concave reflecting surface 43. Is done.

  As described above, according to the present embodiment, among the light components emitted from the LED package 35, the light component having a long path length L passing through the sealing body 95 and biased to the fluorescent color component is converted into the bottom 43 </ b> A of the concave reflecting surface 43. And the LED package 35 are discharged from the reflector 41 to the outside. For this reason, the light biased to the fluorescent color does not enter the concave reflecting surface 43, and the white light can be reflected by the reflector 41 and used as irradiation light.

According to the present embodiment, the white LED includes an LED substrate on which the blue LED is mounted, a gap forming member that is disposed between the bottom of the concave reflecting surface and the LED board and forms the predetermined gap. The gap forming member has insulating properties and flexibility, and a ceramic plate (on which the LED substrate 61 of the LED package 35 is provided on the lighting fixture body 7 by pressing the buffer material 71 by the bottom 43A of the concave reflecting surface 43) The high heat conductive member 37 is in close contact.
With this configuration, each LED package 35 can be brought into close contact with the ceramic plate 37 without variation when the reflector 41 is assembled, and can be cooled uniformly and satisfactorily.

  It should be noted that the above-described embodiment is merely an aspect of the present invention, and can be arbitrarily modified and applied within the scope of the present invention.

1 LED lighting equipment (LED floodlight)
7 Lighting fixture body 33 Light source unit 35 LED package (white LED)
37 Ceramic plate 41 Reflector 43 Concave reflective surface 43A Bottom 61 LED substrate 63 Light emitting part 65 LED (blue LED)
71 Cushioning material (gap forming member)
95 Sealing body (resin)
θth threshold angle K1, K2 Light component L1, L2 Path length

Claims (2)

In an LED lighting apparatus equipped with a white LED as a light source, encapsulating a blue LED in a resin in which a phosphor is dispersed and obtaining white light by mixing the emission color of the blue LED and the fluorescence color of the phosphor,
It has a concave reflecting surface with an opening at the bottom, and includes a reflector in which the white LED is arranged at the opening at the bottom.
Of the light component emitted from the white LED between the white LED and the bottom of the reflector, the bottom opening is located above the white LED , and the distance passing through the resin is long and biased toward the fluorescent color component. Provided with a predetermined gap for entering the light component ,
An LED lighting apparatus, wherein a light component biased toward the fluorescent color component is emitted from the gap to the outside of the reflector, and a light component without bias is reflected by the reflector . The white LED is an LED substrate on which the blue LED is mounted;
A gap forming member disposed between the bottom of the concave reflective surface and the LED substrate and forming the predetermined gap;
The said space | gap formation member has insulation and a softness | flexibility, and is pressed by the bottom part of the said concave-shaped reflective surface, and closely adheres the said LED board to the high thermal conductivity member by the side of an instrument main body. LED lighting fixtures.

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