JP2005109228A - Led device and led illumination apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED device wherein the radiation of heat from LEDs mounted on a board is accomplished well for the suppression of temperature rise, and to provide an LED illumination apparatus. <P>SOLUTION: The LED device 3 comprises a plurality of LEDs 8, a board 7 and a copper foil 10 formed on the two surfaces 7a and 7b of the board 7, with the copper foil 10 occupying similar areas of the two surfaces and with the copper foil 10 on the surface 7a formed into circuit patterns 11a and 11b for mounting LEDs 8, and a heatsink 9 arranged to be in contact with the copper foil 10 on the surface 7b of the board 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an LED device and an LED lighting device in which a plurality of LEDs are mounted on a substrate.

When a plurality of LEDs mounted on a circuit board are turned on simultaneously, a lot of heat is generated. Due to this heat, the temperature of the LED rises, and it tends to have a short life due to deterioration of the resin. Further, when the temperature of the LED rises, the luminous flux decreases. Therefore, in general, a heat dissipating means is provided to dissipate the heat of the LED. For example, an LED lighting device is provided in which a back surface of a metal base plate on which an LED is not mounted is brought into contact with a part of the lighting device to dissipate heat (see, for example, Patent Document 1).
Japanese Unexamined Patent Publication No. 2003-124528 (page 6, FIG. 5)

  Patent Document 1 has a drawback that it is expensive because an LED is formed on a metal base plate via an insulating layer instead of a general circuit board.

  An object of the present invention is to provide an LED device and an LED lighting device in which an LED mounted on a substrate is sufficiently radiated to suppress a temperature rise.

  The invention of the LED device according to claim 1 is a copper foil having a plurality of LEDs; a copper foil formed on one and the other surfaces so that the respective occupancy ratios are substantially equal, and a circuit pattern copper foil on one surface And a substrate on which the LED is mounted; and a heat dissipating means arranged in contact with the copper foil on the other surface of the substrate.

  In the present invention and each of the following inventions, each configuration is as follows unless otherwise specified.

  The LED may be either a surface-mounted type that is surface-mounted on a base or a bullet-type that has a lead frame attached to the base.

  The fact that the respective occupation ratios of the copper foils are substantially equal means that the difference in the occupation ratios is allowed to be 5%.

  The circuit pattern is a current path that supplies current to each of the plurality of LEDs.

  According to the present invention, the heat of the LED is immediately transferred from the copper foil on one side of the base to the base, transferred from the base to the copper foil on the other side, and further transferred to the heat radiating means and dissipated. . Therefore, the temperature rise of the LED is suppressed, and the deterioration of the LED resin or the decrease of the luminous flux is suppressed.

  The invention of the LED device according to claim 2 is the LED device according to claim 1, wherein the occupancy ratio of each copper foil area to each surface area of one and the other surfaces of the substrate is 70% or more, And the difference of the said occupation rate is 5% or less, It is characterized by the above-mentioned.

  When the occupancy is 70% or more, the copper foil area becomes large, so that the heat of the LED is easily transferred to the copper foil on one side, and heat is transferred or released from the copper foil on the other side. That is, the thermal resistance from one surface of the substrate to the other surface is reduced. And when the difference in the occupation ratio is 5% or less, the amount of heat transferred from the copper foil on one side and the amount of heat released from the other side are substantially balanced, so that heat transfer is facilitated, and The temperature difference between the surface and the other surface is reduced, and the substrate is prevented from warping. It was confirmed that the conditions where the occupation ratio is 70% or more and the difference between the occupation ratios is 5% or less are experimentally good for suppressing the temperature rise of the LED.

  According to the present invention, the occupancy of each copper foil area with respect to the surface area of each of the one and other surfaces of the substrate is 70% or more, and the difference in the occupancy is 5% or less, It was confirmed that the heat of the LED was dissipated well by the heat dissipating means and the substrate was not warped.

  The invention of the LED device according to claim 3 comprises the LED device according to claim 1 or 2; an LED lighting device body in which the LED device is disposed; and a lighting device for lighting the LED. It is characterized by that.

  The lighting device is configured by an AC-DC conversion device, a voltage adjustment device, or the like that emits light (lights) the LED, and may be provided in the LED lighting device body or may be provided separately from the LED lighting device body.

  According to the present invention, since the LED device according to claim 1 or 2 is provided, an LED illumination device is provided in which the temperature rise of the LED is suppressed and the decrease of the luminous flux is suppressed.

  According to the first aspect of the present invention, the heat of the LED is dissipated by the heat dissipating means via the one and the other copper foils of the base, so that the temperature rise of the LED can be suppressed to a predetermined value or less, and the LED resin Degradation or decrease in luminous flux can be suppressed.

  According to the invention of claim 2, the occupancy ratios of the respective copper foil areas with respect to the respective surface areas of the one and the other surfaces of the substrate are both 70% or more, and the difference between the occupancy ratios is 5% or less. Accordingly, the heat of the LED can be radiated favorably by the heat radiating means, and the warpage of the substrate due to the temperature difference between one and the other surfaces of the substrate can be prevented.

  According to the invention of claim 3, since the LED device according to claim 1 or 2 is provided, it is possible to provide an LED lighting device in which the temperature rise of the LED is suppressed and the decrease of the luminous flux is suppressed.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 2 show an embodiment of the present invention, FIG. 1 shows an LED lighting device, (a) is a partially cutaway schematic front view, (b) is a bottom view, and (c) is ( FIG. 2 is a partial cross-sectional view of the LED device.

  An LED lighting device 1 shown in FIG. 1 is a direct-mounted lighting fixture disposed on a ceiling surface 2, and includes an LED device 3, a lighting fixture body 4 as a LED lighting device body, a lighting device 5, and an adapter 6. It is configured.

  The LED device (LED module) 3 includes a base 7, a surface-mounted LED 8, and a metal base 9 as a heat dissipation unit.

  The base body 7 is made of, for example, a substantially planar glass epoxy, and has an outer shape of, for example, 20 × 20 mm and a thickness B of about 1.1 mm. As shown in FIG. 2, a copper foil 10 is formed on one surface 7a and the other surface 7b, and circuit patterns 11a and 11b for energizing the LEDs 8 are formed on the copper foil 10 on the one surface 7a. The thickness C of the copper foil 10 is 0.035 mm. An LED 8 is mounted between the circuit patterns 11a and 11b.

  Then, the occupancy ratios of the respective copper foils 10 to the respective surface areas of the one and the other surfaces 7a, 7b of the base body 7 are both 70% or more, and the difference between the respective occupancy ratios is 5%. A copper foil 10 is formed on the surface of the substrate 7 so as to be as follows.

  The LED 8 emits white light, for example, and has a well-known configuration. Then, for example, a current of 20 mA flows by the applied voltage of 3.5 V between the circuit patterns 11a and 11b to emit light. That is, the power P per LED 8 is 0.07W. The LED 8 is mounted on the one surface 7a of the base 7 so that the distance d between the LEDs 8 and 8 is 4 mm. The distance d between the LEDs 8 and 8 is derived from an empirical formula (conditional formula) d ≧ 14 × B ^ 0.52 × C ^ (− 0.1) × P ^ 0.63. In the empirical formula, the symbol ^ represents a power. Symbols B, C, and P indicate the thickness of the base 7, the thickness of the copper foil 10, and the power per LED 8, respectively.

  The metal base 9 is made of, for example, aluminum, and has an outer shape that is substantially the same as the size of the base body 7 and has a thickness of, for example, 3 mm. And the metal body 9 is arrange | positioned so that the copper foil 10 of the other surface 7b of the base | substrate 7 may contact (contact | adhere). Moreover, as shown in FIG.1 (c), the recessed part 13 which follows the lead wires 12 and 12 from the central part vicinity to one end part is formed.

  The LED device 3 is formed as described above. In FIG. 1, the luminaire main body 4 is formed in a frame shape with openings 14 and 14 on the upper surface and the lower surface, and the LED device 3 is disposed therein. That is, the edge of the LED device 3 is supported by the lighting fixture body 4, the metal base 9 closes the opening 14 on the upper surface, and the one surface 7 a of the base 7 and the LED 8 face the opening 14 on the lower surface. And the lighting fixture main body 4 is supported by the adapter 6 by screwing the upper surface of the metal body 9 to the attachment plate 16 connected to the connecting pipes 15 and 15 of a predetermined length made of metal.

  The adapter 6 is formed in a substantially cylindrical shape, and houses the lighting device 5 therein. A pair of electrode blades (not shown) are provided on the upper surface side. This electrode blade is inserted into an electrode blade insertion hole (not shown) of the hooking ceiling 17 disposed on the ceiling surface 2, and the adapter 6 is rotated to turn the power supply electrode (not shown) of the hooking ceiling 17. ) And electrically connected. The power pole of the hook ceiling 17 is electrically connected to a commercial AC power source by a power cord (not shown) wired on the back side of the ceiling surface 2.

  The electrode blade of the adapter 6 is electrically connected to the input terminal of the lighting device 5. Further, lead wires 12 and 12 are led out from the output terminal of the lighting device 5, and the lead wires 12 and 12 pass through the inside of the connecting pipes 15 and 15 and the recess 13 of the metal base 9, so that the common input portion of the base body 6 is inserted. It is connected to the.

  The lighting device 5 includes an AC-DC converter, a voltage regulator, and the like, and causes each LED 8 to pass a current of, for example, 20 mA to light (emit) the LED 8. And when LED8 lights, white light will be radiate | emitted from the opening 14 of the lower surface of the lighting fixture main body 4. FIG.

  Next, the operation of the embodiment of the present invention will be described.

  When power is supplied from the lighting device 5 to the common input section of the LED device 3, each LED 8 is lit (emits light).

  When the LED 8 is turned on (emits light), the heat from the LED 8 is diffused and transferred to the copper foil 10 on the one surface 7a of the base body 7 (heat spreader effect). Then, heat is transferred to the copper foil 10 on the other surface 7 b of the base body 7 through the base body 7. Since the metal base 9 is disposed on the other surface 7b so as to contact the copper foil 10, the heat transferred to the copper foil 10 on the other surface 7b is transferred to the metal base 9, mainly metal. Heat is radiated from the surface of the base 9 and the metal mounting plate 16. Here, the copper foil 10 and the metal base 9 are not necessarily in close contact with each other, and the copper foil 10 exerts a heat spreader effect. Therefore, if there is a partial contact, the required heat dissipation characteristics can be obtained. . As described above, the heat of the LED 8 is radiated and the temperature rise of the LED 8 is suppressed. As a result, the decrease in the luminous flux from the LED 8 is suppressed, the deterioration of the coating resin is prevented, and the life is extended.

  And the copper foil 10 of the one surface 7a of the base | substrate 7 and the copper foil 10 of the other surface 7b are formed so that it may become a 70% or more occupancy with respect to the surface area of each base | substrate 7, and each, It is formed so that the difference in the occupation ratio is 5% or less. Therefore, a large amount of heat of the LED 8 is transferred to dissipate heat, and thus the temperature rise of the LED 8 is suppressed to a predetermined value or less. Further, since the temperature difference between the one surface 7a and the other surface 7b of the base body 7 is small, the base body 7 is prevented from being warped. These were confirmed in the experiment. As a result, the heat radiation means such as the metal base 9 can be easily brought into contact with the copper foil 10 on the other surface 7b of the base body 7, and the LED device 3 or the LED lighting device 1 is formed at low cost.

  Further, if the distance d between the LEDs 8 and 8 is the above-described empirical formula (conditional formula) d ≧ 14 × B ^ 0.52 × C ^ (− 0.1) × P ^ 0.63, the temperature rise of the LED 8 It was confirmed that the temperature difference between the one surface 7a and the other surface 7b of the substrate 7 was 10 ° C. or less.

  And since the LED lighting apparatus 1 comprises the LED apparatus 3 mentioned above, the temperature rise of LED8 is suppressed and the reduction | decrease of a light beam is suppressed.

  The heat radiating means is not limited to the metal base 9 but may be a heat radiator such as a heat radiating fin, or may be an attachment body or a chassis for directly attaching the lighting fixture body 4 to the ceiling surface 2 or the like.

BRIEF DESCRIPTION OF THE DRAWINGS It is an LED illuminating device which shows one embodiment of this invention, (a) is a partially notched schematic front view, (b) is a bottom view, (c) is a top view of the AA direction of (a). Similarly, the partial cross section figure of the LED device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... LED lighting apparatus 3 ... LED apparatus 4 ... Lighting fixture main body 5 as LED lighting apparatus main body ... Lighting device 6 ... Base | substrate 8 ... LED
9 ... Metal stand as heat dissipation means

Claims (3)

A plurality of LEDs;
A substrate on which LEDs are mounted by forming copper foils on one and other surfaces so that the respective occupation ratios are substantially equal, and forming a copper foil of a circuit pattern on one surface;
Heat dissipation means disposed in contact with the copper foil on the other side of the substrate;
An LED device comprising: The occupancy ratio of each copper foil area with respect to the surface area of each of the one surface and the other surface of the substrate is 70% or more, and the difference between the occupancy ratios is 5% or less. LED device. An LED device according to claim 1 or 2;
An LED lighting device body in which the LED device is disposed;
A lighting device for lighting the LED;
LED lighting device characterized by comprising.

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