KR20110001453U - LED mount structure for the shear plane of PWB or material of radiant heat. - Google Patents

Abstract

The mounting (or mounting) structure of the LED for the purpose of increasing the heat dissipation effect of the LED, the LED 201 is mounted on the end portion 204 of the printed circuit board or the heat dissipation member and the surface 203a of the printed circuit board or the heat dissipation member And the LED component leads 202a and 202b at 203b, and the structure of the light emitting body by the LED mounted at the end of the printed circuit board or the heat dissipation member in which the electrical connection means 205a and 205b and the control component 6C11 are located. to be.
It is a proposal that can expect high performance heat dissipation effect at a relatively low price. By increasing heat dissipation effect, LED can be operated at rated or higher level to increase LED utilization efficiency, and it is easy to arrange LED clusters more densely than before. In addition, also in the construction of a display device or a surface light emitting body, it is possible to configure a network that is simpler and easier to handle than in the related art.

Description

Structure of a light emitting body by an LED mounted on an end of a printed circuit board or a heat radiating member {LED mount structure for the shear plane of PWB or material of radiant heat.}

The present invention relates to the mounting (Mount) of the LED illuminant for constituting the LED lighting fixture.

In particular, it relates to the mounting (or mounting) structure of the LED for the purpose of increasing the heat dissipation effect of the LED is to provide a structure and shape suitable for configuring a variety of LEDs and various uses at a relatively low price.

Light emitting diodes (LEDs), also known as light emitting diodes, have the advantages of longer lifespan, less heat generation, faster response time (time to current to shine through light bulbs), and various shapes than light bulbs. It is a semiconductor that has recently been spotlighted as a light source for various lighting as a light emitting body.

LED's appearance is applied to various purposes such as circular round, cylindrical flat type, super / high flux type, and power LED type and chip and surface mount type for various purposes.

Since a single LED has a limitation in using for lighting purposes, tens or hundreds or more LEDs are clustered to form an LED array. A means for this role is usually a printed wiring board (PWB). boards have been used. The printed circuit board must have a component location where the LED or other component is mounted and a copper foil layer for electrically connecting them. According to the number of copper foil layers, a single copper foil layer is used on one surface for printed circuit boards, and a copper foil layer on each surface and a back is used for double-sided printed circuit boards, and a multilayer printed circuit board is molded with other copper foil layers other than the surface and back surface. Are separated. In this printed circuit board, the copper foil is fixed and mutual insulation is maintained. The base material is used for the purpose of adapting to the external environment such as physical external force, temperature and humidity, and the user's purpose.The poly resin substrate (PP material: phenol in kraft paper) Synthetic resin and laminated substrate), epoxy resin substrate (Epoxy Resin, GE material: substrate made of epoxy resin on glass fiber and laminated), composite base material (CPOGITE Base Material, CPE material: two or more materials) Synthesized and laminated substrates. Generally, substrates made by synthesizing cellulose in glass), flexible substrates (copper coated with polyester or polyimide film), and ceramic substrates (ceramic conductor paste). Printed substrates, metal substrates (METAL Cored Base Material) There are various editions).

In such a printed circuit board, it can be made usable when manufactured through a mounting process in which components are placed at a planned position on the substrate surface and a soldering process for electrically connecting the components. For this reason, the component surface and the solder surface on the surface and the back surface of the printed circuit board are reliably classified and treated as functions. In this relationship, there are cases where the component surface and the solder surface are different from each other and the component surface and the solder surface are located on the same plane. The parts also have lead wires for electrical connection to the outside. Soldering should be made to this component lead and may be in good condition when a reliable electrical connection is applied to the component lead.

LED light source is semi-permanent because it is semiconductor, but it is damaged or deteriorated by forward overvoltage, reverse overvoltage due to heat generated by small amount of impurities, noise of electric circuit, and transient phenomenon. It is a very important problem to operate it to produce sufficient light output.

In the heat dissipation structure of LED lamp USING CONVECTIVE FLOW, the heat dissipation structure of LED lamp using convection is effectively released, which extends the life of LED module and improves luminous efficiency. The present invention relates to a heat dissipation structure of an LED lamp using convection, which can be induced to form a heat dissipation hole for inducing convection of air in a main plate.

In the A Apparatus of Heat Radiation for LED Lighting Lamp, a heat dissipation structure that efficiently dissipates heat by transmitting heat generated in LEDs to a heat dissipation cover through a heat pipe. Posted about

In the Republic of Korea Patent Office Patent No. 1009912820000 (20101026) LED Apparatus using an integral heat dissipation structure (Lighting Apparatus using LED), the heat sink is formed at regular intervals, the reflection cover fixed to the front of the body, the LED (LED) is installed ( In the LED lighting device consisting of a printed circuit board, the LED is to be provided with a seating surface formed at a predetermined interval on the top of the heat sink.

In the Republic of Korea Patent Application No. 10-2009-0044240 (20090521) to form a plurality of pipe-type heat dissipation tube in the interior of the lamp, the length of each heat dissipation tube is formed differently so that the inflow and discharge of the outside air smoothly by the convection phenomenon It relates to a heat dissipation structure that can maximize the heat dissipation efficiency of the light emitting diode.

In addition, there have been a number of proposals, but their common feature is that the LEDs must be clustered and arranged in order to form an LED light emitting plane composed of a relatively wide plane. At this time, a plate-like structure such as a printed circuit board is used. It relates to improvements that inhibit convection and worsen cooling performance.

Convection is a form of transport of heat, such as conduction and radiation, in which physical quantities such as heat are transported by the movement of a fluid (in this case, air). Vertical movement is called convection. Separate.

The LED is generally marketed under the designation "It is a LED for 30mA." This is, of course, an example of using a part of the specification based on an ambient temperature of 25 degrees Celsius in place of the type name of the part. However, for LEDs on the market that are traded for 30mA, the actual range of current is not limited to 30mA. The reason why current is regarded as an important factor is that since the LED is a current-driven semiconductor device such as a transistor, the output of the LED, that is, the light output, has a correlation with the magnitude of the current.

Current (mA) Voltage (V) Brightness (LUX) 10 2.90 102 20 3.07 157 30 3.20 203 40 3.31 243 50 3.41 283 60 3.50 317 70 3.57 346 80 3.64 370 90 3.70 393 100 3.76 413 110 3.83 434 120 3.88 449 130 3.94 462 140 3.99 473 150 4.04 480 160 4.10 484 170 4.15 480 180 4.20 470

The diagram above shows the results of testing and measuring one type of LED that is marketed for 30mA. The result is that a 30mA LED can increase brightness up to 160mA. That is, it has a potential use capacity of about five times that of the commonly used range.

After 160mA, the increase of the current indicates the decrease of the light output and is not available.

There are many reasons why LEDs that can increase brightness up to 160mA are used for 30mA, but the primary cause is deterioration and destruction due to temperature rise. Of course, it cannot be used for a long time with excessively high current due to problems other than the temperature rise problem. However, if the 30mA LED is used in the range of 20mA in the field, it can be seen as a very wasteful factor. The present invention is to propose an efficient heat dissipation structure and LED mounting structure that can utilize this potential use capacity.

The heat generation of the LED can be drawn out by the heat conduction of the component lead or the package material from the heat generating source. The heat thus displayed can be conducted to the heat dissipation member, the heat sink and the like. However, without proper convection heat cycles, heat storage will not be able to cool the heat generated by the components. Thus, the circulation of heat by convection is the center of heat radiation.

In the conventional LED array, a convection circulation structure is deteriorated by a printed circuit board (PWB) manufactured for the purpose of densely arranging the LEDs on the surface in all directions. The present invention updates the structure so that the printed circuit board (PWB) or the heat dissipation member located on the same plane as the LED is located on the other side of the LED, thereby extending the natural passage of heat moved in the vertical direction and smoothly venting. Doing.

It is a proposal that can expect high performance heat dissipation effect at relatively low price. By increasing heat dissipation effect, LED can be operated at rated current or higher to increase LED utilization efficiency, and densely arrange LED clusters. It is easy to configure a display device or a surface light-emitting body, which makes it possible to construct a network which is simple and easy to handle as compared with the prior art.

1 shows an LED mounting method on a conventional printed circuit board.
Fig. 2: Structure of the light emitting body by the LED mounted at the end.
Fig. 3: Unit module for multiple replication with multiple numbers of LEDs.
Fig. 4: Heat dissipation of the LED mounted at the end.
Fig. 5: LED array structure for constructing a surface light-emitting body or display screen using the LED.
Figure 6: LED connection means in the unit module.
Figure 7: Example of extension application.

The end is a shortening of shearing, which refers to the cut part when a flat plate is cut to a suitable size, but in this design, the length having the smallest value in a material consisting of a cuboid. In general, the printed circuit board is intended to refer to a plane including a cut portion, but in the case of a heat dissipation member that may be formed by casting or molding, there may be no cutting portion or ambiguity, thereby limiting meaning.

1 shows an embodiment of mounting an LED on a conventional printed circuit board.

1 shows a case where the component surface and the solder surface are different from each other. 103a is the component surface of FIG. 1 and 103b is the solder surface of FIG. Fig. 101 is an LED as a component element, and 102a and 102b are a component lead of an LED, 105 is a copper foil of a soldering surface, and in this case, it is a copper foil corresponding to a part for soldering a component lead. 106 indicates that the component leads 102a and 102b are soldered onto the land 105.

Of course, components (surface mounted components) may be mounted on the same plane. At this time, LED as a component element is used as a kind belonging to the surface-mounted component, and mainly uses only one side which is a component surface and at the same time has a soldering surface, and the other surface is fixed to an external apparatus, adhesion for mechanical attachment, etc. Used for This form is illustrated in FIG. 3A or 5A.

In this conventional printed circuit board, the LED mounting aspect constitutes a completed circuit by using a component surface or a solder surface, and end portions 104 and 3A04 of the third surface constitute an outline of the printed circuit board. There was no specific use except for mechanical coupling with external structures.

Figure 2 is an embodiment showing the core content of the present invention. In Fig. 2, 201 is an LED as a component element. 202a and 202b are the component leads of the component element LED, 203 is the base material of the printed circuit board, 204 is the end of the base material of the printed circuit board, 205a and 205b are the same copper foil as the circuit pattern for connection with the component lead, and 206 Indicates that the component leads 202a and 202b and the copper foils 205a and 205b are soldered.

Comparing FIG. 2 with FIG. 1, the LED is not located at the component surface but at the end 204 of the third surface of the printed circuit board. That is, the LED 201 in FIG. 2 is located on the component surface 103a in FIG. 1, but is located at the end 204 of the printed circuit board in FIG. 2. It is a feature of the present invention.

In FIG. 2, preferably, the base material 203 of the printed circuit board is a heat radiation member made of a metal material such as aluminum. In addition, although FIG. 201 shows a high flux type LED, the LED having a cylindrical or power type other surface mount type may be mounted at an end portion in a manner appropriate to the present invention as shown in FIG. 2. Therefore, within the spirit of the present invention, it is easy for the appearance of LEDs such as cylindrical flat type, super / high flux type, and power LED type to be mounted on the end of the printed circuit board instead of the component surface. It can be recognized.

Leads 202a and 202b of the LEDs are conductive wires directly drawn from the LED 201 junctions, and are heat transfer portions of the LEDs that can be quickly transferred as the temperature increases. 1, the LED 101 standing upright on the component surface of the printed circuit board (PWB) passes through the thickness of the printed circuit board (103: about 2mm or so), reaches the soldering surface, and is cut after being soldered. At this time, the component leads 102a and 102b remain about 3 to 4 mm as a thermal conductor, but such component leads are depressed in the base material 103 and thus insufficient to exhibit a heat dissipation function by convection.

According to Fig. 2, it is possible to secure long enough soldering spots 205a and 205b, so that the component leads 202a and 202b (25 mm or more in the case of cylindrical LEDs) can be used as heat dissipation means without cutting. In addition, since the component leads 202a and 202b as the thermal conductor are exposed on the surface of the printed circuit board or the heat radiating member, cooling by convection is easy.

The specification of the end portion 204 providing such mounting of the LED may be made of a conventional heat sink (aluminum or copper plate). In this case, the separation between the component leads 202a and 202b and the heat dissipation plate material 203 as an insulating material having excellent thermal conductivity is easy for those skilled in the art.

In the heat dissipation plate 204, bending a thin plate (preferably copper or aluminum) rather than a thick material to form a 'c' shape to form an end 204 for mounting the LED 201. This is easy for those with ordinary knowledge in the field.

In addition, to manufacture a printed circuit board 203 with a metal substrate (METAL Cored Base Material: a substrate made of aluminite after aluminite treatment) to realize an embodiment of the present invention is also common in the art. It is easy for those with knowledge.

In addition, the application of mounting the LED 201 at its end 204 in a double-sided substrate 203 made of conventional phenol or epoxy resin is also easy for those skilled in the art, and in such an application, a printed circuit It is desirable to secure a larger heat dissipation area to the copper foil surfaces 205a and 205b of the substrate 203, which is also easy for those skilled in the art.

In case that the brightness of unit LED is not enough or it is used as a good surface emitting light source, it is necessary to construct LED array by mounting two-dimensional array of LEDs on a plurality of planes. It is also necessary to create a screen with an LED array to construct a display for the display.

3 shows an example of configuring an LED strip for arranging and grouping a plurality of LEDs as an embodiment of the present invention.

3A is an example of a conventional LED strip and FIG. 3B is an example of an embodiment of the present invention. 3A01 in FIG. 3A is an LED, and surface mount LEDs are mainly used in this strip form. 3A03 is a board for mounting a component, and a printed circuit board is generally used. Electronic components 3A10 other than LEDs may be mounted on the surface (part surface) of the substrate and may be used alone or attached to a heat radiating member.

3B is an embodiment configured as claimed in the present invention, and the LEDs 3B01 are mounted in a plurality of rows at the third surface end 3B04 of the heat dissipation member or the printed circuit board. On the surface 3B04 of the heat dissipation member or the printed circuit board, the component lead 3B02 of the LED, as well as a means for electrical connection (copper pattern: 3B05 on the printed circuit board), and an electronic component 6C11 other than the LED 3B01. May be mounted.

Therefore, a circuit configuration for driving the LED 3B01 or additional components for control are installed on the third surface 3B04 on which the LED 3B01 is mounted, and on the other surface 3B05, so that the degree of freedom of mounting is high. The LEDs 3B01 may be mounted on the heat dissipation member or the end of the printed circuit board 3B05 in a plurality of densely arranged or arranged at appropriate intervals, which means that the degree of freedom is high in the arrangement of the LEDs 3B01.

For the verification of the heat dissipation effect in the strip-shaped assembly proposed in FIG. 3B, the embodiment shown in 3B as dozens of LEDs was fabricated, and this was produced in a horizontal posture of 3A and a vertical posture of 3B. The following diagram shows an example of the temperature rise experiment after operating each by changing only the posture.

Minutes Horizontal posture Vertical position Temperature (℃) Current (mA) Temperature (℃) Current (mA) 0 30.2 681 30.0 675 5 43.0 708 31.6 682 10 50.3 720 32.4 682 15 53.2 724 32.9 671 20 54.5 735 33.3 665 25 56.2 726 33.7 671 30 56.8 725 34.0 670 35 56.7 726 34.1 668

The heat-dissipating member used in this test is aluminum plate, which is 3mm thick and cut into 550mm × 35mm, and the LED is a white high flux type with 54 connected in series and operated by DC260V.

It can be seen that the difference between temperature rise and conduction current is significant depending on whether the posture is upright or horizontal in the same specimen, and the heat dissipation performance is superior in the vertical posture.

4A and 4B illustrate the convection and heat dissipation problems in use with respect to FIGS. 3A and 3B, respectively. 4A20 is a schematic of the air flow. 4A shows that the heat accumulating portion 4A21 is widely shown during convection by the relatively wide heat dissipating member 4A03 positioned horizontally. Compared with FIG. 4A, in FIG. 3B, the convection phenomenon accelerated by the wall surface of the heat radiating member 4B03, which is wide enough, can cause the heat of the heat radiating member to flow more easily. I can understand that it is done. 4B20 is a schematic of the flow of air. Therefore, the convection performance improvement effect by the heat dissipation member of the posture other than the horizontal posture is a feature of the present invention.

In order for LED to be used for lighting, the light output must be increased. For this purpose, the current needs to be increased and the problem of heat generation due to the increased current is a big problem, and therefore, it must be used at the rated current for reliable operation. In light of the point that the loss is reduced, the purpose of the present invention, which is advantageous for heat dissipation by convection, may be useful. In particular, the conventional heat dissipation member has a complicated shape to help convective cooling, and according to the present invention, it is possible to use a heat dissipation plate having a simple shape.

FIG. 5 shows an LED array structure for constructing a surface light-emitting body or display screen using LEDs.

5A is an example of a conventional LED array structure. The LEDs 5A01 are arranged on a plane 5A03, which usually includes a printed circuit board and is attached to the heat dissipation member 5A30 by means of an electrical insulation layer. For convection, holes are also induced in the plane of the printed circuit board.

5B shows an end-mounted LED array structure insisted by the present invention. 5B01 is an LED, 5B02 is a component lead of LED, and 5B03 is a printed circuit board or a heat radiating member. This arrangement structure is an assembly of a two-dimensional array structure in which the LED strip 3B of the LED strip shape of FIG. 3B is used as a unit module, and has a structure that can realize various surface emitting areas.

Preferably, the unit modules should be configured to be penetrating without bending or bending in the passage of the air flow in order to maximize the cooling effect due to convection.

In natural convection, the flow of air flows from the bottom to the top, so it is a feature of the present invention to configure the unit module to follow the natural flow of air.

The LED has a current value corresponding to a specific brightness and the voltage required to flow this current is determined. In which group of LEDs are the LEDs connected in series

In this case, it is determined by the voltage of the power supply = the voltage required for one LED x the number of LEDs. The number of LEDs mounted in the unit module according to the proposal of the present invention is characterized by the result of the calculation as described above determined by the magnitude of the supply power supply voltage.

As described above, the unit module manufactured in the present inventive concept may simply constitute a surface light emitting body by adding and removing the same number of unit modules according to the size and shape of the surface light emitting body. Thus, the unit module may be manufactured in a detachable structure. It is a structure that is convenient for replacement is easy to those of ordinary skill in the art and the surface light-emitting body composed of a unit module is one of the features of the present invention as a structure that provides convenience for repair and repair.

6 shows the LED connection means in the unit module. In Fig. 6, 6A is a parallel connection and 6B is a series connection. The series connection connects two adjacent component leads. In parallel connection, all adjacent component leads are connected. This connection structure is simple and repetitive, so it is easy to handle. Other electrical connections such as conventional dip and soldering processes, as well as ultrasonic welding or spot welding. It provides a structure that is easy to apply the means and is one of the features of the present invention.

6C illustrates a connection structure suitable for display. The component leads of the LED exposed to the surface 6C03 of the printed circuit board or the heat dissipation member from the LED 6C01 mounted on the third surface and the end of the printed circuit board or the heat dissipation member are connected to the control circuit mounted on the same plane. It is individually connected to the component 6C11. Since the surface (or back surface) of the printed circuit board or the heat radiating member may be provided with a sufficiently wide plane 6C03, sufficient space is easily secured, and thus, a conventional high cost structure is not required, such as using a multilayer board as in the prior art. It is not possible to realize a simple and easy-to-repair device compared to the conventional display array, which has a complicated design of a circuit pattern of a matrix structure or a difficulty in analyzing or repairing a circuit. One of the features.

LEDs have a small emission angle, which creates a concentrated area of illumination. In order to compensate for this tendency, various diffusion mechanisms may be applied.

Fig. 7 shows an example of the shape of the base materials 7A03 and 7B03 in the unit module advantageous for such a diffusion structure. The contour of the end where the LED is to be mounted forms an elliptical or circular arc contour, and the LEDs are placed on the contour to form a unit module that produces diffused light. Such a unit module has a characteristic of easily making diffused light of LED light emission by arranging a portion of a circular arc or a columnar shape as shown in FIG. 7C.

In order to maximize the cooling effect by convection when combining a plurality of unit modules, the fan 7D40 does not need to bend or warp in the passage of the air flow, and in addition, the fan 7D40 insists that the present invention constitutes a through type. Forming the accelerated air stream 7D20 in the air passage is easy, the effect is doubled, and can have useful results such as low noise of low power consumption due to low air resistance.

The first letter is Tavern
The second and third characters
01: LED
02: LED part lead
03: Base Material
04: end
05: Connection part such as land or copper foil.
06: soldering
10,11: control parts
20,21: the flow of air.
30: heat dissipation member
40: Fan
The fourth character is an auxiliary mark.

Claims (13)

The LED 201 is mounted on the end portion 204 of the printed circuit board or the heat dissipation member, and the LED component leads 202a and 202b are positioned on the surfaces 203a and 203b of the printed circuit board or the heat dissipation member, and the electrical connection means 205a. And 205b) and the structure of the light emitting body by the LED installed at the end of the printed circuit board or the heat dissipation member in which the control part 6C11 is located. According to claim 1, the LED is formed on the end of the printed circuit board or the heat dissipation member consisting of any one of the shape of the round round, cylindrical flat, super / high flux, and the power LED type and chip. Structure of the light emitting body by the LED to be installed. The structure of a light-emitting body according to claim 1, wherein the electrical connection means is mounted at an end portion of a printed circuit board or a heat dissipation member which is made of soldering or dip soldering. The structure of a light-emitting body according to claim 1, wherein the electrical connection means is provided at an end portion of a printed circuit board or heat dissipation member which is made of ultrasonic welding or spot welding. The structure of a light emitting body according to claim 1, wherein an end portion of the heat dissipation member is a single aluminum plate or an LED mounted on an end portion of a heat dissipation member or a printed circuit board made of injection molding or extrusion molding. The structure of a light emitting body according to claim 1, wherein an end portion of the heat dissipation member is formed of a thin plate metal bent in a 'c' shape or is mounted at an end of the heat dissipation member. The structure of a light emitting body according to claim 1, wherein the printed circuit board is made of a base material made of phenol or an epoxy resin, or an LED mounted on an end portion of a printed circuit board made of a metal substrate (METAL Cored Base Material) or a heat radiating member. The LED 201 is mounted on the end portion 204 of the printed circuit board or the heat dissipation member, and the LED component leads 202a and 202b are positioned on the surfaces 203a and 203b of the printed circuit board or the heat dissipation member, and the electrical connection means 205a. And 205b) and a control circuit 6C11 in which the number of LEDs 3B01 mounted at the end of the printed circuit board or the heat dissipation member is made up of a plurality, and the printed circuit board constituting the unit module 3B for multiple replication or Structure of the light emitting body by the LED installed at the end of the heat dissipation member. The structure of a light emitting body according to claim 8, wherein the LED is provided at an end portion of a printed circuit board or a heat dissipation member to form a unit module of the LED whose number of LEDs is determined by the magnitude of the supply voltage. The printed circuit board according to claim 8, wherein in the unit module 3B, the end portion of the printed circuit board or the heat dissipation member has a straight line or a circle, or a part or all of the arcs of the ellipse, or a shape 3B, 7A, or 7B. Structure of the light emitting body by the LED installed at the end of the heat dissipation member. The LED 201 is mounted on the end portion 204 of the printed circuit board or the heat dissipation member, and the LED component leads 202a and 202b are positioned on the surfaces 203a and 203b of the printed circuit board or the heat dissipation member, and the electrical connection means 205a. And 205b) and the control part 6C11, the number of LEDs 3B01 mounted at the end of the printed circuit board or the heat dissipation member is composed of a plurality of units, and a plurality of unit modules 3B for a plurality of replications are arranged. The structure of the light emitting body by LED mounted in the edge part of the printed circuit board or heat radiating member which forms cluster 5B. The printed circuit board or the heat dissipation member according to claim 11, wherein the unit modules are arranged and arranged (7C) according to the shape of a flat or an ellipse, a part of a circle, a part of a circle, or a part of a cylindrical shape or a sphere when forming a group of light emitting bodies. Structure of the light emitting body by the LED installed at the end. 12. The structure of the light emitting body according to claim 11, wherein the LED is provided at an end of a printed circuit board or a heat dissipation member in which a fan (Fan: 7D40) is provided in the convective passage (7D20) of the group of light emitting bodies.

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