JP2000149151A - Heat radiation structure for light emitting diode lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively radiate heat emitted by LED from a lamp body and a globe through a filling material and a supporting main body since a part of the supporting main body is made in close contact with the lamp body and the globe, to improve light emitting efficiency since the temperature rising in LED can be prevented and to improve the radiation luminous intensity of a lamp unit. SOLUTION: This heat radiation structure has an LED 1, a substrate 2, a supporting main body 3, a filling material 4 and a glove 5. The lead part of LED is soldered to the conduction pattern of the substrate 2. The supporting main body 3 is the good conductor of heat and it supports the substrate 2 between the lead part and solder through the thermally conductive and non- electrically conductive filling material 4 and radiates heat from a flange part 11. The globe covers LED 1 by leaving the heat radiation face of the supporting main body 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiating mechanism for emitting a warning, a signal, information, or the like, such as a marker light or a signal light, and using a light emitting diode (hereinafter, referred to as "LED") as a light source. Since LEDs have a longer life than light bulbs, they are suitable for long-term continuous use such as sign lights, and have been widely used in recent years. However, with lighting, L
When the temperature inside the ED increases, there is a property that the luminous efficiency decreases and the luminous intensity decreases. For this reason, it is important to internally cool the LED to quickly discharge the heat generated inside the LED.
The present invention provides an effective means for cooling an internal LED mounting portion of a lamp using an LED as a light source.

[0002]

2. Description of the Related Art An example of a conventional technique for improving the internal cooling of a lamp of this type is disclosed in JP-A-4-121901.
No. (hereinafter referred to as “A”) is known. This is because, in order to promote heat radiation inside the lamp, the lamp has a structure in which the upper base (4) is hollow and the lower is a cup-shaped stay (6), and a plurality of ventilation holes are provided on the side surface. A power source (7) is housed in a central part of the stay (6).
Japanese Patent Application Laid-Open No. 9-69304 (hereinafter referred to as "B") has a similar purpose. This is to improve the heat radiation by providing a radiator (56) at the top of the lamp.

[0003]

However, in the prior art as described above, the LEDs are mounted on a printed circuit board (No. 3, No. 33). In this mounting state, although the figure is small and the details are not clearly shown, the printed circuit board (No. 3, No. 33) includes a supporting body (No. 4: Base, No. 32: (The unit body), and is separated by an air layer, so that the heat transfer between the LED and the base 4 or the unit body 32 depends on the air, and the cooling effect is limited.

Generally, an LED element is mounted by soldering with a lead portion penetrating through a hole in a printed circuit board. At this time, an energizing pattern is formed on the opposite side of the LED body, and the lead is penetrated here and soldered, so that the solder and the lead protrude. When they come into contact with the metal supporting body, they are electrically short-circuited and do not operate normally. That is, it is considered that an air layer is always interposed, and heat conduction is restricted. Also, LE
Even if the tip of the lead of D and the metal support body are not in direct contact with each other, if the gap is narrow, there is a danger that a short circuit may occur due to lightning or the like due to electric discharge.

[0005]

According to the present invention, a heat radiating structure for a light emitting diode lamp includes a light emitting diode, a substrate, a support body, a filling, and a globe. The light-emitting diode has its lead portion inserted through a hole in the substrate and fixed to a conducting pattern on the back surface of the substrate by soldering,
It is attached to the substrate. The supporting body is composed of a good heat conductor, supports the substrate via the heat conductive and non-electrically conductive filler between the lead portion and the solder, and has a flange portion attached to the lamp body. The glove is supported and forms a heat radiating surface. And, the globe covers the light emitting diode.

A printed circuit board on which the LED is mounted;
An air layer interposed between the LED and the metal part by filling and solidifying a thermally conductive and electrically insulating filler between the thermally conductive and electrically conductive support body supporting the substrate. Disappears. Then, the heat generated from the LED is quickly conducted to the supporting body via the filling material, and is radiated to the outside from the heat radiation surface of the supporting body. For this reason, the luminous intensity of the lamp is increased, and the problem of the related art has been solved.

[0007] The substrate may have flexibility, the support body may have a conical cylinder part, and the substrate may be supported along the outer surface of the conical cylinder part. In this case, it is easy to wind the substrate around the outer periphery of the conical cylindrical portion, and the regulation imposed on the aviation obstruction light, that is, the light distribution suitable for the whole circumference in the horizontal direction and the vertical direction from 15 ° downward to just above can be performed. 6. Upward of the specified luminous intensity
It can easily handle 5 mm.

[0008] The substrate may have flexibility, the support body may have a cylindrical portion in part, and may support the substrate along an outer surface of the cylindrical portion. As described above, the flexible substrate is easily wound around the outer periphery of the cylindrical portion. The light projection direction is the entire circumference in the horizontal direction.

[0009] A spacer may be provided between the support body and the substrate at a distance from each other, and the filler may be filled between the support body and the substrate except for the spacer. In the case of a rigid substrate, it is sufficient to have spacers in at least two places, but in the case of a flexible substrate, the spacing between the spacers is determined by the interval at which adjacent spacers support the substrate so as not to contact the substrate. . In the case of a rigid substrate as well as a flexible substrate, a filler can be filled between the substrate and the support body excluding the spacer.

The supporting body is box-shaped having an opening on one surface and has a recess on the other surface, leaving a stepped surface. The substrate is attached to the stepped surface covering the recessed portion on the back surface, and the opening is formed on the substrate. The glove may be covered. In this case, the substrate may be flexible or rigid. Light is emitted in one direction. Suitable for lighting used for inspection and identification of industrial products. Further, the present invention can be applied to a case where a large number of LEDs are used in the same structure, a control circuit capable of individually blinking the LEDs is added to display characters and symbols, and the display is used as a guide light or other indicator light or sign light.

The filler may comprise a mixture of silicone rubber and a curing agent. As an example of a thermally conductive and electrically insulating filler, a heat-dissipating silicone rubber has recently been sold. Among these, there is a type in which a narrow space is filled by mixing and injecting a hardening agent into a liquid base material and hardening over time. By injecting this filler into the gap between the printed circuit board on which the LED is mounted and the support body and curing the air, the air is almost completely exhausted, and the heat transfer between the printed circuit board and the support body is remarkable by this filler. To improve. In addition, the discharge that can occur when the lead end of the LED and the metal supporting body are close to each other while maintaining a space is suppressed by the filler.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment in which the present invention is applied to an aviation obstacle light will be described with reference to the drawings. The right half of FIG. 1 is an external view, and the left half is a cross-sectional view. The light distribution of this aviation obstruction light is specified by red light in a range from 15 ° downward to just above in the horizontal direction and up and down in the horizontal direction.
The maximum value of the specified luminous intensity is the upward 7.5 ° direction. For this reason, the LED is mounted at an angle of 7.5 ° all around.

1 is an LED, 2 is an LED substrate, 3 is a support body, 4 is a filler, and 5 is a glove. As can be seen from FIG. 6, the LED 1 has its lead portion 6 inserted through the hole 7 of the substrate 2 and fixed to the energizing pattern 9 printed on the back surface 8 of the substrate 2 with solder 10 and attached to the substrate 2. I have.

The support body 3 is made of a good heat conductor, supports the substrate 2 between the lead portion 6 and the solder 10 through a thermally and electrically non-conductive filler 4, and has a flange portion 1
1 is attached to the lamp body 12 and supports the globe 5 to form a heat radiation surface 13.

The globe 5 is attached to the flange 11 of the support body 3 as described above, and covers the LED 1.

In the illustrated example, the flange portion 11 of the support body 3 is provided.
Is attached to the flange portion 14 of the lamp body 12. The lighting circuit 1 is located below the central cavity 15 of the support body 3.
The lighting circuit 16 and the pattern 9 of the board 2 are connected by a connector 18. The terminal block 2 is stored in the terminal block storage section 19 below the lamp body 13.
0 is stored, and the power supply line 21 is connected.

The upper surface of the flange portion 12 of the support body 3 is used for mounting the globe 5. The substrate 2 is screwed to the support body 3 at upper and lower edges and is in close contact with the support body 3, but at an intermediate portion, the outer surface of the support body 3 is depressed and a temporary gap is provided between the two. . This is, as mentioned above,
This is to prevent the fixing portion of the ED 1 by the solder 10 from coming into contact with the support body 3.

The substrate 2 needs to be attached to the entire periphery of the support body 3, and may be rigid or flexible.
In this embodiment, the substrate 2 is attached in three parts. The alignment of the substrate 2 is suppressed by a substrate holder 22, and the substrate 2 is regulated so as to have a correct cylindrical or conical shape.
The cross-sectional shape of the substrate holder 22 is an inverted T-shaped cross-section to ensure the required bending rigidity, and a notch (not shown) is provided at a portion in contact with the substrate 2 to avoid contact with the lead portion 6 of the LED 1. Is provided.

The temporary gap between the LED substrate 2 and the support main body 3 is eliminated by filling the heat radiation filler 4. This filling is performed by attaching the substrate 2 to the support main body 3 and then injecting a fluid filler through an inlet 23 provided on the upper surface of the support main body 3. A plurality of injection ports 23 (three in this embodiment) are provided.
The air is exhausted from another inlet 23, and the filler 4 comes into close contact with the substrate 2 and the support body 3. In addition, an O-ring 24 is attached to the lower end of the temporary gap to prevent the filler 4 from leaking during injection. Note that F is the lamp body 12
These are fins for heat radiation provided in the.

With the above configuration, the LED 1
The heat generated inside the LED is led by the lead 6 of the LED 1 and the substrate 2.
The power transmission pattern 9 formed on the back surface 8 of the substrate 2 and the heat conductive filler 4 filled on the back surface 8 side of the substrate 2 are transmitted to the support body 3. And a part of this heat is
The heat is transmitted from the radiating surface 13 to the lamp body 12 to the outside through the fins F, and a part of the heat is transmitted from the heat radiating surface 13 to the globe 5 and is discharged to the outside. The air in the vicinity of the LED 1 is heated by the heat of the LED 1, rises to a high temperature, rises, dissipates heat through the globe 5, and descends along the central space 15 of the support body 3 as the temperature decreases, and radiates heat to the support body 3. Circulate while circulating. The radiance of the lamp in this case is about 20%
Improved.

In FIG. 1, the substrate 2 has flexibility, and the supporting body 3 has a conical tube portion 25 in a part thereof, and supports the substrate 2 along the outer surface of the conical tube portion 25. In this case, the substrate 2
It is easy to wind around the outer periphery of the conical tube portion 25, and the regulation imposed on the aviation obstruction light, that is, the horizontal direction is the entire circumference, and the vertical direction can perform a light distribution suitable for the range from 15 ° downward to directly above,
It can easily cope with an upward direction of 7.5 ゜ of the specified luminous intensity.
In this case, the substrate 2 is bent into a conical surface shape and attached to the conical cylindrical portion 25, and the filler 4 is filled between the two. This structure is higher in rigidity and superior in vibration resistance than the structure in which a narrow LED board is screwed at three places as seen in the conventional example. You get the angle. Further, since the number of substrates 2 is reduced, the processing of the substrates 2 is facilitated, and there is an advantage that the number of bottles to be mounted is reduced.

In FIG. 4, the substrate 2 has flexibility, the support body 3 has a cylindrical portion 26 in a part, and supports the substrate 2 along the outer surface of the cylindrical portion 26. In this case, the flexible substrate 2 can be easily wound around the outer periphery of the cylindrical portion 26 as described above. In this case, the substrate 2 is bent into a cylindrical surface shape and the cylindrical portion 26 is formed.
And the filler 4 is filled between the two. This structure is higher in rigidity and excellent in vibration resistance than a structure in which a narrow LED board is screwed at three places as in the conventional example. Further, since the number of substrates 2 is reduced, the processing of the substrates 2 is facilitated, and there is an advantage that the number of bottles to be mounted is reduced.

A spacer 27 is provided between the support body 3 and the substrate 2 at a distance from each other.
The filler 4 is filled between the support body 3 and the substrate 2 excluding 7. In this way, even in the case of the flexible substrate 2, a gap to be closed by the filler 4 can be secured between the support body 3 and the substrate 2. Although FIG. 2 shows the case where the horizontal angles are arranged at intervals of 40 °, this angle is appropriately determined. These spacers 27 are adhered and attached between the rows of the LEDs 1, thereby preventing the spacers 27 from contacting the solders 10 of the lead portions 6 of the LEDs 1 and making the gaps asymmetric.

FIGS. 5 and 6 show examples in which the present invention is applied to a flat lamp. The support body 3 has a box shape having an opening 28 on one surface, and has a concave portion 30 on the other surface while leaving a step surface 29. Glove 5 is covering. In this case, the substrate 2 may be flexible or rigid. Light is emitted in one direction, which is suitable for an illumination lamp used for inspection and identification of industrial products. Further, by using a large number of LEDs 1 with the same structure and adding a control circuit capable of individually blinking the LEDs 1 to display characters and symbols, the present invention can also be applied to a case where the display is used as a passage guide or other indicator lamps or marker lamps. .

The filling 4 is made of a mixture of silicone rubber and a curing agent. In this way, the filler 4 is injected into the gap 11 between the printed board 2 on which the LED 1 is mounted and the support body 3 and hardened, whereby air is almost completely exhausted. The heat transfer between the support bodies 3 is significantly improved. Also, LE
The discharge, which can occur when the tip of the lead portion of D and the metal supporting body are close to each other while maintaining a space, is suppressed by the filler.

[0026]

According to the present invention, the substrate on which the LED is mounted is supported by the supporting body via an electrically insulating and heat-conductive filler between the supporting body and the supporting body. Because it is close to the lighting fixtures and gloves in part,
The heat generated by the ED can be effectively radiated from the lamp body or the globe through the filler and the support body, and the temperature inside the LED can be prevented from rising, so that the luminous efficiency is improved and the luminous intensity of the lamp can be increased.

According to the second aspect, similarly to the second aspect, the substrate is easily wound around the outer periphery of the conical cylindrical portion, and the regulation imposed on the aviation obstruction light, that is, the horizontal direction is the entire circumference, and the vertical direction is downward. Light distribution suitable for a range from 15 ° to directly above can be performed, and it is possible to easily cope with an upward direction of 7.5 ° of the specified luminous intensity.

According to the third aspect, the flexible substrate can be easily wound around the outer periphery of the cylindrical portion, and can uniformly project light over the entire circumference in the horizontal direction.

According to the fourth aspect, the filler can be filled between the base and the support body excluding the spacer, not only in the case of a rigid substrate but also in the case of a flexible substrate.

According to the fifth aspect, since the light is emitted in one direction, it can be applied to an illuminating lamp used for inspection and identification of industrial products, etc. By adding a control circuit capable of blinking to display characters and symbols, the present invention can also be applied to guide lights and other indicator lights and sign lights.

According to the sixth aspect, the heat transfer between the substrate and the supporting body is remarkably improved, so that the temperature of the LED can be prevented from rising and the radiant intensity can be increased. Discharge that can occur when the support main body is close can also be suppressed.

[Brief description of the drawings]

FIG. 1 is a front view showing, in cross section, a left half portion of an aviation obstacle lamp to which a specific example of a heat radiation structure of a light emitting diode lamp according to the present invention is applied.

FIG. 2 is a plan view of FIG.

FIG. 3 is a bottom view of FIG. 1;

FIG. 4 is a partial cross-sectional view of a modification of FIG. 1, in which the support main body 3 has a cylindrical portion 26;

FIG. 5 is a front view showing a case of a flat lamp.

FIG. 6 is a sectional view taken along line 6-6 in FIG. 5;

[Description of Signs] 1 LED (Light Emitting Diode) 2 Substrate 3 Supporting Body 4 Filler 5 Globe 6 Lead 7 Hole 8 Back 9 Pattern 10 Solder 11 Heat Dissipation Surface

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3K014 AA01 LA01 LB04 5C083 BB10 BB28 DD02 DD06 DD10 JJ30 5F041 AA33 DB01 DC07 DC23 DC66 DC78 DC84 FF16

Claims (6)

[Claims] 1. Light emitting diode (1), substrate (2), support body
(3), a filler (4) and a globe (5), and the light emitting diode (1) has a lead (6) with a hole (7) in the substrate (2).
And a pattern for energizing the back surface (8) of the substrate (2)
(9) is fixed to the substrate (2) by fixing with solder (10), the support body (3) is made of a good heat conductor, and the lead portion (6) and the solder (10) are fixed. ), The substrate (2) is supported via the thermally and electrically non-conductive filler (4), and the flange (11) is attached to the lamp body (12) and the globe is supported. A heat dissipation structure for a light emitting diode lamp, wherein the heat dissipation surface (13) is formed by supporting the light emitting diode (1), and the globe (5) covers the light emitting diode (1). 2. The substrate (2) is flexible, and the support body is
The light emitting diode lamp according to claim 1, wherein (3) partially has a conical tube portion (25) and supports the substrate (2) along an outer surface of the conical tube portion (25). Heat dissipation structure. 3. The support body has flexibility, and the support body is flexible.
3. The heat dissipation structure of a light emitting diode lamp according to claim 1, wherein (3) has a cylindrical portion (26) in part and supports the substrate (2) along an outer surface of the cylindrical portion (26). . 4. A spacer (27) is provided between the support body (3) and the substrate (2) at a distance from each other.
The filler between the support body (3) and the substrate (2) except for (27)
The heat dissipation structure of a light emitting diode lamp according to claim 1, wherein (4) is filled. 5. The support body (3) is box-shaped with an opening (28) on one surface and has a recess (30) on the other surface leaving a step surface (29), and the substrate (2) is provided on the back surface. The heat dissipation structure of a light-emitting diode lamp according to claim 1, wherein the recess (30) is covered with the step (29) and the step (29) is attached to the step surface (29), and the opening (28) is covered by the globe (5). . 6. The heat radiating structure for a light emitting diode lamp according to claim 1, wherein said filler (4) is made of a mixture of silicone rubber and a curing agent.