KR101133649B1 - Electric/electronic apparatus and led apparatus which has high heat-release efficiency - Google Patents

Abstract

An electronic device is provided for improving the efficiency of heat dissipation. For example, this electric and electronic device is an LED light emitting device. An LED light emitting device may include: an LED chip emitting light through a combination of electrons and holes; A printed circuit board (PCB) electrically connected to an electrode unit formed on the LED chip; And a heat sink disposed on an approximately lower surface of the LED chip and the PCB and dissipating heat generated from the LED chip. The PCB has an opening formed at a position corresponding to the LED chip, and the heat sink has a relief portion formed to contact the PCB, but at a position corresponding to the opening of the PCB, to contact the LED chip.

Description

ELECTRIC / ELECTRONIC APPARATUS AND LED APPARATUS WHICH HAS HIGH HEAT-RELEASE EFFICIENCY

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device and an LED light emitting device using a light-emitting diode (LED). More specifically, the present invention relates to an electric electronic device and an LED light emitting device having a structure for improving heat dissipation efficiency of an electric electronic device (for example, LED chip).

Common bulbs used for lighting are generally classified into fluorescent, incandescent, or metallic neon lamps used for industrial purposes, and most of these bulbs are gas discharge tube configurations in which gas is injected into glass tubes. In the case of such a general light bulb, when the gas is leaked due to breakage of the glass tube, it may cause air pollution, and when the brightness is to be brightened, power consumption increases accordingly, and power line construction must be performed accordingly. There were problems such as excessive cost of facility and maintenance.

In addition, in addition to the field of silk lighting, in general, as a display element (including a general dimming push button or dimming lamp) for displaying on the panel whether or not a power source is applied, whether an electric / electronic component or a mechanical element is operating, or a state, is mainly used. Tungsten filament lamps are also used. These lamps have holders that can support and light them, down-trans for converting AC 110V or 220V AC to 24V or 6.3V, or winding resistors for DC power, and luminaires. And a color globe for emitting a predetermined color as well as a pilot lamp. The lamp constructed as described above has good brightness, but the lamp is composed of tungsten filament heating wires, and the filament heating wires may be caused by poor contact with the socket of the lamp, or by an irregular power supply or impact voltage at the time of on / off or due to prolonged deterioration. This disconnection is frequently required and frequent exchange is required. In addition, such lamps may be deformed due to the heat generated from the filament heating wire, the lamps or the globes may be damaged due to shock or vibration, the filaments may be easily broken, and the waterproofing and explosion proof may be difficult to be considered. .

As an alternative to solve the problems of the above-mentioned lighting or display bulbs, in recent years, development of lighting lamps or indicators using LEDs with low power consumption has been proposed. In other words, efforts to use the LED chip as a lighting device to compensate for the above-described disadvantages, LED chip is typically mounted on the PCB to receive power to emit light.

An LED chip is a kind of pn junction semiconductor that emits light through a combination of electrons and holes. For example, an LED chip generates a carrier composed of a few electrons and holes through the flow of electric current. It is one of the semiconductor devices that emit light emitted by the recombination process as light.

Hereinafter, a conventional LED lamp will be described with reference to FIG. 1.

1 is a view showing the structure of a conventional LED lamp (LED lamp).

The LED chip 110 may be mounted on a printed circuit board 120 having a predetermined metal pattern 121 formed on the surface of the insulating material 125, for example, by a die bonding method. The circuit is configured by a wire 130 that electrically connects the LED chip 110 and the metal pattern 121 to emit light by applying current. A schematic operation principle of the LED chip 110 has been described above, and a description thereof will be omitted.

The LED chip 110, which is a semiconductor device, is accompanied by heat generation. In other words, it is preferable that all of the energy generated when the electrons and holes meet is converted to light, but in reality, a large portion of the energy is also converted into thermal energy.

That is, the heat breaks the wire 130 that electrically connects the LED chip 110 and the metal pattern 121, and may cause deterioration of the LED chip 110 due to heat.

Since the high and low heat dissipation effect is directly proportional to the luminous efficiency, the corresponding heat dissipation structure must be supported for sufficient light emitting effect. However, in the conventional LED chip mounting structure, heat generated from the LED chip 110 is generated on the PCB 120. Since it is emitted only through the limited metal pattern 121, the heat dissipation effect is low, and thus there is a limit in mounting the LED chip of sufficient brightness and using it as an illumination (or display) device.

2 shows a conventional example using a metal PCB.

In FIG. 2, the LED chip 110 has an LED heat dissipation pad 210 and a solder joint 220 on its bottom surface. If necessary, a phosphor 110-1 may be formed on the LED chip 110 to correct the color of light emitted from the LED chip 110.

In FIG. 1, the LED chip 110 and the metal pattern 121 are connected through the wire 130, but in FIG. 2, the solder joint 220 (which serves as the wire 130 of FIG. 1) is somewhat different from this. It can be seen that through the circuit connection unit 230 (which serves as the metal pattern 121 of FIG. 1).

Below the LED chip 110, a metal PCB 280 is present. The metal PCB 280 includes a circuit connection unit 230, an adhesive 1 240, an insulation cloth 250, an adhesive 2 260, and a metal ( 270).

3 illustrates a state in which a heat sink is attached to the example of FIG. 2.

A heat conductive plate of a high heat transfer material (usually a metal) is attached to the bottom of the structure as shown in FIG. 2, wherein a heat conductive paste is disposed between the metal 270 of the metal PCB 280 and the heat sink 310 to increase thermal conductivity. Apply 320. The heat sink 310 typically includes a plurality of heat sink fins.

FRP PCB, epoxy PCB and the like are also available, but the reason for using a metal PCB as shown in Figure 2, is to increase the heat dissipation efficiency by attaching the heat sink 310 as shown in FIG.

As shown in FIG. 2, it can be seen that the metal PCB 280 has a multilayer structure in performing surface mount. That is, an insulation cloth 250 for insulation must be inserted between the circuit connection portion 230 (for example, made of copper foil (copper foil)) and the metal 270, and the circuit connection portion 230 and the insulation cloth ( Adhesive 1 240 is required to bond 250, and adhesive 2 260 is required to bond insulating cloth 250 and metal 270.

Such dissimilar materials include barriers to the direct and rapid release of heat generated by the LEDs into the heat sink.

This phenomenon is also called thermal resistance, and the thermal resistance increases as the resistance value increases through various other objects, which interferes with dissipating heat generated from the LED toward the heat sink.

In particular, when the thermally conductive paste 320 is added as shown in FIG. 3, it can be predicted that the heat resistance will be somewhat increased due to the combination of different materials.

According to the present invention, an electrical and electronic device; A printed circuit board (PCB) electrically connected to an electrode unit formed in the electrical and electronic device; And a heat sink disposed on an approximately lower surface of the electric electronic device and the PCB, the heat sink for dissipating heat generated from the electric electronic device, wherein the PCB has an opening formed at a position corresponding to the LED chip. Is in contact with the PCB, but at the position corresponding to the opening of the PCB is provided with an electrical and electronic device characterized in that it has an embossed portion formed to contact the electrical and electronic device.

Preferably, the embossed portions of the electric and electronic elements and the heat sink are in contact with each other via a heat radiation pad.

Preferably, the heat radiation pad is made of metal.

Preferably, the PCB is an epoxy resin PCB or a FRP resin PCB.

Preferably, the PCB is a metal PCB.

Preferably, when viewed in plan view, the embossed portion of the heat sink is smaller than the opening of the PCB.

Preferably, the heat sink and the embossed portion of the heat sink are integrally formed of the same material.

Preferably, the heat sink has a heat dissipation fin on the opposite side of the contact surface with the PCB in order to efficiently dissipate heat.

Preferably, the heat sink, the heat sink fins and the embossed portion of the heat sink are integrally formed of the same material.

According to the present invention, as the LED light emitting device, the electric and electronic device described in any one of the above items is a light-emitting diode chip that emits light by the combination of electrons and holes. The heat dissipation pad is provided with an LED light emitting device which is an LED heat dissipation pad.

According to the present invention, since the LED chip and the heat sink are in direct contact or contact with only a minimum inclusion (for example, an LED heat pad), the heat dissipation efficiency can be improved.

In the past, when heat sinks were used to increase the efficiency of heat dissipation, metal PCBs, which are relatively expensive than resin PCBs, had to be used and the bottom surface of the metal PCB had to be in contact with the heat sinks. Interposed between the metal PCB and the metal PCB has an insulating cloth or adhesive layer in the middle, thereby tending to increase the thermal resistance (that is, although the heat dissipation efficiency is improved compared to without the heat sink) Inherent limitations existed), and in the present invention, since the thermal resistance inherently blocks a room for intervention, the advantages of the heat sink can be more reliably enjoyed.

According to the present invention, although the use of the metal PCB is not excluded, it is possible to achieve at least the same or much better heat dissipation efficiency as in the case of using the metal PCB while using a resin PCB which is cheaper than the metal PCB.

That is, the heat dissipation pad of the LED can be directly connected to the heat sink without using a conventional PCB (resin agent, etc.) as a substitute for an expensive metal PCB and distinguishing whether it is a metal PCB or a general PCB. The invention can make a great contribution not only to increase heat dissipation efficiency but also to lower the manufacturing cost.

1 is a view showing the structure of a conventional LED lamp (LED lamp).
2 is a view showing a conventional example using a metal PCB.
3 is a view showing a state that the heat sink is attached to the example of FIG.
4 is a view showing an embodiment of the present invention.
5 is an exploded perspective view of the cross-sectional view of FIG. 4.
6 is a diagram illustrating an embodiment of an LED arrangement.
7 is a view showing another embodiment of the LED arrangement.
8A and 8B are photographs showing an embodiment of the LED device shown in FIG. 7.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a view showing an embodiment of the present invention.

As shown in FIG. 4, an embodiment according to the present invention includes an LED chip 410, a phosphor 420 (if necessary), a PCB 430, and a heat sink 440.

The LED chip 410 is a kind of pn junction semiconductor that emits light through the combination of electrons and holes. For example, the LED chip 410 generates a carrier composed of a few electrons and holes through the flow of electric current. Is one of the semiconductor devices that emits energy emitted by light in the process of recombination of holes and light.

The phosphor 420 serves to correct the color of light emitted from the LED chip 410.

The material of the PCB 430 may be any material commonly used. That is, the PCB 430 of the embodiment of the present invention may be made of epoxy resin, FRP resin, or the like, and may be a metal PCB. However, as will be described later, since the heat dissipation effect can be obtained by the unique structure of the present invention, even if the metal PCB, the PCB 430 of the present invention is an epoxy resin PCB or FRP resin PCB, etc. It will be economical to use them.

In addition, the heat sink 440 is coupled as shown in FIG. An embossed portion 440-1 is formed at a predetermined portion of the heat sink 440. The predetermined portion means a portion facing the LED chip 410. In addition, the PCB is opened (opened) at the portion where the embossed portion 440-1 of the LED chip 410 and the heat sink 440 face each other, so that the embossed portion 440-1 of the LED chip 410 and the heat sink are fitted. It is accessible.

Although the LED chip 410 and the embossed portion 440-1 are described as being in contact with each other, the two LEDs 410 are not directly in contact with each other, but rather than the direct contact between the LED chip 410 and the upper surface of the embossed portion 440-1. The spring would be reasonable to include through a thin member such as 450, and it would be sufficient if a portion of the PCB 430 corresponding to the contacting portion was opened.

In detail, the heat dissipation paste 320 is attached to the heat dissipation plate 310 using the metal PCB 280, etc. In this case, the heat dissipation plate 310 and the metal PCB 280 are attached to the heat dissipation pad 450. Compared to the problem of voids caused by incomplete flatness of the LED, the heat dissipation pad 450 is usually made of metal, and has a smaller volume to be connected than the method of attaching the heat dissipation paste. For this reason, the metal-to-metal is directly connected, which may have a maximum heat dissipation effect.

In addition, the production of a non-polar heat dissipation pad of the LED component is also the trend of the production of LED packages these days, so there is often no electrical signal through the heat dissipation pad, so it will not be difficult to connect it directly to the heat sink.

That is, one embodiment of the present invention includes an LED chip 410 that emits light through a combination of electrons and holes, and includes a PCB 430 electrically connected to an electrode formed on the LED chip 410. Located on the lower surface of the LED chip 410 and the PCB 430, and has a heat sink 440 for dissipating heat generated from the LED chip 410.

The electrode part is a part that is an electric path through which an electrical signal or electric power of the LED chip 410 can enter and exit. As shown in FIG. 4, the electrode part is connected to the circuit connection part of the PCB 430 through the solder joint 460. to be. As shown in the figure, the electrode portion is generally present at the edge of the LED chip 410, but is not necessarily limited to this position.

The lower surface of the LED chip 410 and the PCB 430 is sufficient if the lower surface of the PCB 430 is lower than all sides, and the lower surface of the LED chip 410 is strictly embossed 440-1. It is an expression used to clarify that it is not completely present on the bottom surface of the PCB 430 (although it is actually located under the PCB 430, etc.) as it fits into the opening, which means those skilled in the art Will be clearly identified.

In addition, the PCB 430 has an opening formed at a position corresponding to the LED chip 410, and the heat sink 440 contacts the PCB 430, but at the position corresponding to the opening of the PCB 430, the LED chip 410. ) Has an embossed portion 440-1 formed to contact the.

5 is an exploded perspective view of the cross-sectional view of FIG.

The phosphor 420 is formed on the LED chip 410, and the solder joint 460 and the LED heat dissipation pad 450 are formed on the bottom surface of the LED chip 410.

The solder joint 460 is in contact with the circuit connection portion present on the upper surface of the PCB 430 to electrically connect the LED chip 410 and the circuit connection portion of the PCB 430.

Although the specific configuration of the PCB 430 is not described in FIG. 4 or 5, a metal PCB may be used, or a PCB made of FRP resin, an epoxy resin PCB, or any other PCB may be used. The upper surface of these PCBs is typically composed of electrical wiring (ie, circuit connection), which may refer to FIG. 2 and the like.

And the circumference of the PCB 430 shown in FIG. 5 indicates that the plurality of LED chips 410 may be formed in an arbitrary pattern, and thus the pattern of the PCB 430 may vary. do. In addition, the PCB 430 of FIG. 5 is not particularly marked, but typically, the PCB may be formed of two or more layers. For example, as shown in the metal PCB of FIG. 2, the circuit connection part may be formed of an adhesive, an insulating cloth, an adhesive, a metal, and the like. something to do.

A predetermined portion of the PCB 430 is opened, and through this opening, the bottom surface of the LED chip 410 (exactly, the LED heat dissipation pad 450 attached to the bottom surface of the LED chip 410) and the heat sink 440 to be described later. The relief portion 440-1).

The heat sink 440 is present under the PCB 430. This heat sink 440 has an embossed portion 440-1 different from the flat top surface of a normal heat sink. The embossed portion 440-1 is preferably made of the same material integrally formed with the heat sink 440. In addition, since it must be in contact with the LED heat radiation pad 450 of the LED chip 410 through the opening of the PCB 430, the size of the protruding portion of the relief portion 440-1 is preferably less than the size of the opening. However, if there is a special situation whether the embossed portion 440-1 protrudes in double, only the uppermost layer of the protruding portion may be smaller than the size of the opening.

In this case, the size refers to the size when viewed from the top view, but is shown in side view in Figure 4 and a perspective view in Figure 5, but the size relationship on the plan view when viewed from the top surface embossed through the opening It is clear that the portion 440-1 may be in contact with the LED chip 410. As such, the relief 440-1 of the heat sink is smaller than the opening of the PCB 430.

In FIG. 5, the shapes of the relief portions 440-1 and the openings are all rectangular, but are not necessarily limited thereto. The relief portion 440-1 and the opening portion may be circular, elliptical, or any other shape.

In addition, the relief portion 440-1 and the opening portion do not have to have the same shape. For example, the opening portion may have a rectangular shape, and the relief portion 440-1 may have a circular shape. However, even in this case, it is a matter of course that the size relationship is set so that the relief portion 440-1, or at least the top layer structure of the relief portion, can enter the opening.

In addition, the circumference of the heat sink 440 of FIG. 5 is displayed in a wavy pattern, similar to the case of the PCB 430, and the plurality of embossed portions 440-1 have a predetermined pattern (that is, the upper LED chip 410). ), Which means that the pattern of the relief 440-1 may vary. In addition, although not shown in the heat sink 440 of Figure 5, it is preferable that the heat radiation fin is formed as shown in Figure 4 below. That is, the heat sink 440 may have a heat radiation fin on the opposite side of the contact surface with the PCB 430 in order to efficiently discharge heat.

Although not necessarily limited thereto, the embossed portion 440-1, the heat dissipation plate 440, and the heat dissipation fin are preferably integrally formed of the same member. Of course, if the material has a high thermal conductivity, it will be possible to form a different material to be in close contact with each other. Depending on the situation, from the standpoint of convenience and efficiency of manufacture, it may be possible to determine whether to form a single piece or to attach it separately, and usually a single piece would be preferable.

6 illustrates one embodiment of an LED arrangement.

A plurality of LEDs may be formed with the arrangement of FIGS. 4 and 5 described above, an example of which is the same as FIG. 6.

That is, in FIG. 5, waves are displayed on the PCB 430 and the heat sink 440 in order to have an arbitrary arrangement. As an example, the LED chip 410 and the phosphor 420 are illustrated in the front view of FIG. 6. ) May be arranged on the PCB 430. Each of the LED chips 410 is properly connected in series and parallel relationship. The serial-parallel relationship may be properly adjusted by circuit connections engraved on the PCB 430.

Although not shown in FIG. 6, an opening is formed at a corresponding position of the LED chip 410 of the PCB 430, and an embossed portion 440-1 is formed at a corresponding position of the heat sink 440. 4 and 5 will be readily appreciated.

7 shows another embodiment of an LED arrangement.

A plurality of LEDs may be formed with the arrangements of FIGS. 4 and 5 described above, another example of which is the same as FIG. 7.

That is, in FIG. 5, waves are displayed on the PCB 430 and the heat sink 440 in order to have an arbitrary arrangement. As an example, the LED chip 410 and the phosphor 420 are shown in the front view of FIG. 7. ) May be arranged on the PCB 430. Each of the LED chips 410 is properly connected in series and parallel relationship. The serial-parallel relationship will be properly controlled by the circuit connections engraved on the PCB 430.

Although not shown in FIG. 7, an opening is formed at a corresponding position of the LED chip 410 of the PCB 430, and an embossed portion 440-1 is formed at a corresponding position of the heat sink 440. 4 and 5 will be readily appreciated.

8A and 8B are photographs showing an embodiment of the LED device shown in FIG. 7.

FIG. 7 shows the state where the LED chip is attached, and FIGS. 8A and 8B show only the printed circuit board (PCB) before the LED chip is attached (although the arrangement state of the space to which the LED chip will be attached differs from FIG. 7). 8A is a plan view and FIG. 8B is a bottom view.

In the bottom view of FIG. 8B, the dark colored portion is an electrical wiring pattern. The pattern is not exposed to the outside from the bottom and is covered with a separate insulating layer. Due to the nature of the resin material, the electrical wiring pattern may be visible.

8A and 8B is not a metal PCB, but the resin material is easily bent and there is no disconnection or performance deterioration due to the warp, and there is no economical deterioration due to the use of a metal PCB since the resin PCB is used, and an embossed heat sink according to the present invention. As a result, the heat dissipation effect is greatly improved compared to the case of using a metal PCB.

On the other hand, even when using the same LED chip, the performance such as the luminous efficiency is not always the same, there are many factors affecting the performance such as the luminous efficiency, but one of them is the temperature. In other words, the performance of the same LED chip may vary depending on how effective the heat dissipation is.

On the other hand, although the embodiment of the present invention has been described as using an LED chip, those skilled in the art will appreciate that the present invention is not only an LED chip, but also general electric and electronic devices (for example, active devices or combinations thereof, passive devices or combinations thereof, ICs). It will be readily appreciated that the present invention can be applied to a chip). In particular, since the heat generation is a problem in the LED chip is described as a great example, it is obvious that the structure is capable of effectively dissipating heat generated from the electric transfer device even if the LED chip.

Although specific examples have been described above, the present invention is not limited to the above embodiments, and many modifications are possible within the essential spirit of the present invention as set forth in the appended claims by those skilled in the art. Of course. Various other modifications should be considered to be within the scope of the present invention, without departing from the basic spirit of the invention.

110: LED chip
110-1: phosphor
210: LED heat dissipation pad
220: solder joint
230: circuit connection
240: adhesive 1
250: insulation cloth
260: adhesive 2
270: metal
280: PCB (metal)
310: heat sink
320: thermally conductive paste
410: LED chip
420: phosphor
430: printed circuit board
440: heat sink
440-1: Embossed part of the heat sink
450: LED heat dissipation pad
460: solder joint

Claims (10)

Electrical and electronic devices;
A printed circuit board (PCB) electrically connected to an electrode unit formed in the electrical and electronic device; And
Located on the lower surface of the electrical and electronic device and the PCB, the heat sink for dissipating heat generated in the electrical and electronic device
Equipped with
The PCB has an opening formed at a position corresponding to the electrical and electronic device,
The heat sink is in contact with the PCB, the electrical and electronic device characterized in that it has a relief formed to contact the electrical and electronic device at a position corresponding to the opening of the PCB. The method of claim 1,
An embossed portion of the electric transfer element and the heat sink are in contact with each other via a heat dissipation pad therebetween. The method of claim 2,
The heat dissipation pad is an electronic device, characterized in that the metal material. The method of claim 1,
The PCB is an electronic and electronic device, characterized in that the epoxy resin PCB or FRP resin PCB. The method of claim 1,
The PCB is an electronic device, characterized in that the metal PCB. The method of claim 1,
When viewed in plan view, the embossed portion of the heat sink is smaller than the opening of the PCB, the electronic device. The method of claim 1,
The heat sink and the embossed portion of the heat sink is an electrical and electronic device, characterized in that formed integrally with the same material. The method of claim 1,
The heat sink is characterized in that the heat dissipation fin on the opposite side of the contact surface with the PCB in order to discharge heat efficiently. The method of claim 8,
And the heat sink, the heat sink fins, and the embossed portions of the heat sink are integrally formed of the same material. As an LED light emitting device,
The electrical and electronic device according to any one of claims 1 to 9 is an LED chip (light-emitting diode chip) that emits light by the combination of electrons and holes,
The said heat radiating pad of any one of Claims 1-9 is an LED heat radiating pad, The LED light-emitting device characterized by the above-mentioned.

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