US20120298346A1

US20120298346A1 - Bent-type heat dissipater

Info

Publication number: US20120298346A1
Application number: US13/518,689
Authority: US
Inventors: Jang-Hyung Cho
Original assignee: CEDIC CO Ltd
Current assignee: CEDIC CO Ltd
Priority date: 2009-12-24
Filing date: 2010-12-13
Publication date: 2012-11-29
Also published as: WO2011078507A2; WO2011078507A3; KR100970747B1

Abstract

Disclosed is a bent-type dissipater, including one or a plurality of heat sinks which are adapted with cooling apertures; one or a plurality of cooling pins which are bent in structure, and which are integrated to the heat sinks, and a central heat passage for combining heat moving in one direction with ambient air, and discharging the heat in the opposite direction.

Description

TECHNICAL FIELD

The present invention relates to a bent-type heat dissipater, particularly a bent-type heat dissipater that can improve easiness of manufacturing, weight reduction, and heat transfer performance by integrally forming a plurality of heat dissipation fins to be bent, and improve the operational performance of a device with a heat-generating unit by ensuring paths through which heat can flow.

BACKGROUND ART

In general, light emitting diode lamps (hereafter, referred to as ‘LED lighting device’) have the advantage in that economical efficiency is excellent because the efficiency of light to unit power is remarkably high in comparison to incandescent lamps and fluorescent lamps that are presently used.
That is, LEDs have the advantage in that they are eco-friendly and have a long life span because they generate a small amount of carbon and a small amount of heat, in addition to obtaining a desired amount of light from low voltage. Therefore, LEDs have been widely used for lighting devices, which can replace incandescent lamps and fluorescent lamps.
LED lighting devices have a problem in that it is difficult to obtain a desired amount of light due to heat from a plurality of LEDs when being used for a predetermined period of time due to the features and the life span of the LEDs rapidly decreases due to a gradual increase in the amount of generated heat when being continuously used.
In order to solve the problem, LED lighting devices have been configured to dissipate heat to the outside by attaching a heat sink made of metal (for example, aluminum) to the rear side of a substrate equipped with LEDs, in the related art. In this configuration, a plurality of heat dissipation fins for dissipating heat and a plurality of holes (also called discharge holes or convection holes) for passing external air and internal heat are formed at the outer side of the heat sink.
However, since the heat sink of the related art is made of not a single material, but a mixture of several materials, and is manufactured by die casting, performance of heat transfer is not good. Further, there is a problem in that the heat sink is heavy and this makes it difficult to reduce the weight of the device, and the cost increases due to a complicate manufacturing process.
Further, the heat sink has a structure in which the heat generated by the heat-generating unit transfers to the heat sink simply through only a contact type, without an inpassage, that is a passage, for external air which connects the heat-generating unit with the heat sink.
According to the structure, natural convection becomes slow locally only around the holes of the heat sink and the heat generated from the heat-generating units stops and cannot be quickly discharged.
Therefore, the heat generated from the heat-generating unit is not quickly discharged to the outside, such that it is impossible to prevent the heat-generating unit from continuously increasing in temperature, and accordingly, the life span or the function of the LEDs and the parts around are decreased, thus deteriorating the operational performance of the device.

DISCLOSURE

Technical Problem

Therefore, the present invention has been made in an effort to solve the problems in the related art and the first object of the present invention is to provide a bent-type heat dissipater that can be more easily manufactured and can improve heat transfer performance, by forming integral heat dissipation fins by machining one thin metal plate from a single material, and by bending up the integral heat dissipation fins to make the heat dissipater in one structure.
Further, the second object of the present invention is to provide a bent-type heat dissipater that allows heat generated from a heat-generating unit to be quickly discharged to the outside by ensuring a passage through which the heat generated from the heat-generating unit can be discharged outside together with external air.

Technical Solution

In order to achieve the object, a bent-type heat dissipater of the present invention includes: a heat dissipation plate having one or a plurality of cooling holes that form passages to discharge heat, which transfers in one direction, together with external air in the opposite direction; and one or a plurality of heat dissipation fins integrally bent from the heat dissipation plate.
The cooling hole is preferably formed at the center of the heat dissipation plate. Further, it is preferable that the cooling hole is formed in a size of 20 to 80% of the size of the heat dissipation plate. Further, it is preferable that the cooling hole further has a plurality of sub-cooling grooves along the inner circumference.
In this configuration, it is preferable that the heat dissipation fins are inclined at a predetermined angle toward the center with respect to the top of the heat dissipation plate. It is preferable that the inclination angles of the heat dissipation fins are changed by selectively bending.
Further, it is preferable that the heat dissipation fins further have one or a plurality of sub-holes to pass heat, which flows inside from the cooling hole, to the outside.
It is preferable that the heat dissipation fins are integrally bent up along the edge of the heat dissipation plate and have a predetermined length upward.
Meanwhile, it is preferable that the heat dissipation fins are formed at regular intervals, and a plurality of sub-heat dissipation fins is further disposed at the regular gaps between the heat dissipation fins, along the edge of the heat dissipation plate in order to increase a heat dissipation area.
In this configuration, it is preferable that the sub-heat dissipation fins are formed in any one of a shape bent in one direction to have a plurality of steps and a zigzag shape alternately bent in two directions to have a plurality of steps.

Advantageous Effects

As described above, according to the present invention, since the heat dissipation fins are implemented by one thin metal plate made of one material, it is possible to easily manufacture the heat dissipater, reduce the weight, and improve heat transfer performance.
Further, as the sub-heat dissipation fins are further provided, the area coming in contact with air increases, such that the cooling performance can be further improved, and the heat dissipater can function as a main body simultaneously with cooling, such that it is possible to simplify the structure of the LED lighting device. Further, as passages through which the heat generated from the heat-generating unit can be discharged together with the external air to the outside are ensured, the discharge speed of heat is high in a device including a heat-generating unit, such that the performance of the device can be improved.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view showing a bent-type heat dissipater according to the present invention.

FIG. 2 is a perspective view showing when heat dissipation fins of the bent-type heat dissipater according to the present invention are deployed.

FIG. 3 is a bottom view showing sub-cooling grooves formed around a cooling hole of the bent-type heat dissipater according to the present invention.

FIG. 4A is a perspective view showing when the heat dissipation plate of the bent-type heat dissipater according to the present invention is further provided with sub-heat dissipation fins.

FIG. 4B is a perspective view showing the shapes of the sub-heat dissipation fins of FIG. 4A bent in one direction to have a plurality of steps.

FIG. 4C is a perspective view showing the shapes of the sub-heat dissipation fins of FIG. 4A alternately bent in two directions to have a plurality of steps.

FIG. 5 is a disassembly view showing the installation state of the bent-type heat dissipater according to the present invention.

FIG. 6 is a plan view showing the installation state of the bent-type heat dissipater according to the present invention.

FIG. 7 is a front cross-sectional view showing the installation state of the bent-type heat dissipater according to the present invention, taken along line A-A.

FIG. 8A is a view schematically showing temperature distribution according to the diameter of the cooling hole when heat is discharged by the bent-type heat dissipater according to the present invention.

FIG. 8B is a view schematically showing velocity distribution according to the diameter of the cooling hole when heat is discharged by the bent-type heat dissipater according to the present invention.

BEST MODE

Preferred embodiments of the present invention will be described hereafter in detail with reference to the accompanying drawings.
Terminologies defined in description of the present invention are defined in consideration of the functions in the present invention and should not be construed as limiting the technical components of the present invention.
FIG. 1 is a perspective view showing a bent-type heat dissipater according to the present invention. FIG. 2 is a perspective view showing when heat dissipation fins of the bent-type heat dissipater according to the present invention are deployed. FIG. 3 is a bottom view showing sub-cooling grooves formed around a cooling hole of the bent-type heat dissipater according to the present invention. FIG. 4A is a perspective view showing when the heat dissipation plate of the bent-type heat dissipater according to the present invention is further provided with sub-heat dissipation fins. FIG. 4B is a perspective view showing the shapes of the sub-heat dissipation fins of FIG. 4A bent in one direction to have a plurality of steps. FIG. 4C is a perspective view showing the shapes of the sub-heat dissipation fins of FIG. 4A alternately bent in two directions to have a plurality of steps. FIG. 5 is a disassembly view showing the installation state of the bent-type heat dissipater according to the present invention. FIG. 6 is a plan view showing the installation state of the bent-type heat dissipater according to the present invention. FIG. 7 is a front cross-sectional view showing the installation state of the bent-type heat dissipater according to the present invention, taken along line A-A.
FIG. 8A is a view schematically showing temperature distribution according to the diameter of the cooling hole when heat is discharged by the bent-type heat dissipater according to the present invention. FIG. 8B is a view schematically showing velocity distribution according to the diameter of the cooling hole when heat is discharged by the bent-type heat dissipater according to the present invention.
As shown in FIGS. 1 and 2, a bent-type heat dissipater 100 of the present invention includes a heat dissipation plate 110 having one or a plurality of cooling holes 111 that form passages to discharge heat, which is generated in one direction, together with external air in the opposite direction, and a plurality of heat dissipation fins 120 integrally bending up along the edge of the heat dissipation plate 110 and having a predetermined length upward. It is preferable to use aluminum for the material of the heat dissipater of the present invention.
It is preferable that the cooling holes 111 are disposed at the center of the heat dissipation plate. Further, the heat dissipation fins 120 may be arranged at predetermined distances or in contact with each other.
That is, when the heat dissipation fins 120 may be arranged at predetermined distances, the air and heat flowing inside from the outside can be discharged through the upper portions and sides of the heat dissipation fins 120. On the contrary, when the heat dissipation fins 120 are in contact with each other, only the heat can be discharged through the sides of the heat dissipation fins 120.
In this case, one or a plurality of sub-holes 123 may be further formed at the heat dissipation fins 120 to pass the heat, which flows inside through the cooling hole, to the outside. That is, the sub-holes 123 allow the heat and the external air flowing upward through the cooling hole 111 to be easily discharged outside.
Further, insertion holes 121 are vertically formed through the tops of the heat dissipation fins 120 such that a power module 300 (described below) can be combined. Preferably, it may be possible to bend the upper ends of the heat dissipation fins 120 toward the center of the heat dissipation plate 110 to form flat surfaces and then vertically form the insertion holes 121 through the flat surfaces.
Meanwhile, it is preferable to form the cooling hole 111 at the center of the heat dissipation plate 110. Further, the cooling hole 111 may be shaped in any one of a circle, an ellipse, and a polygon. Further, it is preferable to size the cooling hole 111 to be 20 to 80% of the size of the heat dissipation plate 110.
Meanwhile, as shown in FIG. 3, a plurality of sub-cooling grooves 111 a may be formed along the circumference of the cooling hole 111.
The sub-cooling grooves 111 a may be selectively arranged in accordance with the installation direction of LEDs 211, and the length and width of the sub-cooling grooves 111 a may depend on the amount of heat generated by the LEDs 211. That is, the sub-cooling grooves 111 a have orientation to the portions where the LEDs 211 are disposed, such that they have an effect of intensively cooling the portions where a large amount of heat is generated.
It is preferable that the heat dissipation fins 120 are inclined at a predetermined angle toward the center with respect to the top of the heat dissipation plate 110. Further, it is preferable to selectively change the inclination angles of the heat dissipation fins 120 by bending.
The reason of inclining the heat dissipation fins 120 is for further improving heat dissipation performance by concentrating the heat to the upper portion, simultaneously with increasing the contact areas between air and the heat dissipation fins 120 while the air flows upward through the cooling hole 111.
Meanwhile, the heat dissipation fins 120 are formed at regular intervals and a plurality of sub-heat dissipation fins 122 are further disposed at the regular gaps between the heat dissipation fins 120 along the edge of the heat dissipation plate 110 to increase the heat dissipation area.
As shown in FIGS. 4A to 4C, the sub-heat dissipation fins 122 may be formed in any one of a shape bent in one direction to have a plurality of steps and a zigzag shape alternately bent in two directions to have a plurality of steps.
The bent-type heat dissipater 100 is formed in a single structure by integrally forming the heat dissipation fins 120 by machining one plate member, and then bending up the heat dissipation fins 120, as shown in FIG. 2. That is, since the heat dissipater 100 is formed in one integral body, heat easily transfers and the heat dissipation performance is improved.
Further, it is preferable that the inner diameter of the cooling hole 111 is 6.5% to 80% of the outer diameter of the heat dissipation plate 110.
For example, FIGS. 8A and 8B show when the inner diameters of three cooling holes 112, 122, and 131 are set at 6.5%, 22%, 37%, 52%, and 80% of the outer diameter of the heat dissipation plate 110 and then external air flowing inside through the cooling holes and heat generated from a heat-generating unit are discharged upward.
The red parts are where temperature is the highest and velocity is the highest and the blue parts are where temperature is the lowest and velocity is the lowest.
That is, referring to FIG. 8A, it can be seen that as the external air flows inside through the cooling hole formed at the center while air and heat is discharged, the temperature rapidly decreases toward the upper portion. Further, referring to FIG. 8B, it can be seen that the velocity increases toward the upper portion.
The bent-type heat dissipater 100 described above, in accordance with the present invention, can be formed into one lighting device by organically combining an LED module 200 equipped with a plurality of LEDs 211 with a power module 300 supplying power to the LED module 200.
Obviously, the configurations described herein are only examples of preferable installation states of the bent-type heat dissipater 100 and it should be understood that the present invention may be achieved in various ways without being limited thereto.
First, the LED module 200 includes an LED substrate 210 equipped with a plurality of LEDs 211 arranged on the underside and having a first lower cooling hole 212 vertically formed through the center, and a condensing lens unit 220 coupled to the underside of the LED substrate 210, diffusing light generated from the LEDs 211 through lenses 221, and having a second lower cooling hole 222 vertically formed to be connected with the first lower cooling hole 212.
Further, a lens cover 230 may be further disposed under the condensing lens unit 220. On the other hand, as shown in FIG. 10, it should be understood that the condensing lens unit 220 may function as both a lens and a cover by being coupled to the underside of the LED substrate 210 by a cover-fastening member 232 which is described below.
The lens cover 230 has seating holes 233 vertically formed to seat the lenses 221 through the seating holes 233, and a third lower cooling hole 231 vertically formed to be connected (communicate) with the second lower cooling hole 222 of the condensing lens unit 220. That is, the first, second, and third lower cooling holes 212, 222, and 231 and the cooling hole 111 formed at the heat dissipation plate 110 form one vertical passage such that external air can flow inside from below and be discharged upward.
The seating holes 233 may be formed to have a diameter the same or larger than the circumferences of the lenses 21 such that the lenses 21 can pass through them.
Further, the cover-fastening member 232 extending upward and surrounding the third lower cooling hole 231 may be formed on the top of the lens cover 230. A plurality of first locking protrusions 232 a is formed along the circumference at the upper end of the cover-fastening member 232 to protrude outward.
The first locking protrusions 232 a are locked on the cooling hole 111 formed at the heat dissipation plate 110, through the second lower cooling hole 222 and the first lower cooling hole 212. Accordingly, the LED substrate 210, the condensing lens unit 220, and the lens cover 230 can be integrally fixed to the underside of the heat dissipation plate 110.
Further, the lens cover 230, the condensing lens unit 220, and the LED substrate 210 may be fastened to the heat dissipation plate 110 by several fasteners B. That is, when the cover-fastening member 232 is mounted on the lens cover 230, the space inside the cover-fastening member 232 becomes the third lower cooling hole 231 and the space inside the third lower cooling hole 231 forms one vertical passage for taking external air inside and discharging heat.
For this configuration, it is preferable that the outer diameter of the cover-fastening member 232 is the same as the diameters of the first, second, and third lower cooling holes 212, 222, and 231 and the cooling hole 111 formed at the heat dissipation plate 110, which are described above.
The power module 300 includes an upper holder 310 having terminal holes 311 at the upper portion and seated on the upper ends of the heat dissipation fins 120, a power substrate 320 fitted in the upper holder 310 from below such that connection terminals 321 disposed at the upper portion are inserted in the terminal holes 311 to be exposed upward, and a lower holder 330 fitted on the lower portion of the upper holder 310 and supporting and preventing the power substrate 320 from being separated outward.
In this structure, a plurality of second locking protrusions 330 protrudes outward from the sides of the upper holder 310. Further, inclined surfaces (not given a reference number) that are inclined upward and outward from the ends connected to the upper holder 310 may be formed on the undersides of the second locking protrusions 312.
Further, a plurality of locking holes 331 is horizontally formed through the upper portion of the lower holder 330 that is fitted on the upper holder 310 to fit the second locking protrusions 312 therein.
Further, a plurality of insertion protrusions 313, which protrude outward above and adjacent to the second locking protrusions 312 and then extend downward, is further formed on the sides of the upper holder 310.
That is, the upper ends with the locking holes 331 of the lower holder 330 open outward while sliding on the inclined surfaces formed on the undersides of the second locking protrusions 312 and are restored by elastic restoring force at the ends of the inclined surfaces, such that the second locking protrusions 312 are fitted. Therefore, the upper holder 310 and the lower holder 330 can be firmly combined.
Further, when the power module 300 is fixed on the upper portions of the heat dissipation fins 120, the insertion protrusions 313 of the upper holder 310 are inserted into the insertion holes 121 formed at the tops of the heat dissipation fins 120.
Meanwhile, at least one or more cable holes 332 may be formed through bottom of the lower holder 330 to pass cables (not shown). That is, cables (not shown) extending from the power substrate 320 are electrically connected to the LED substrate 210 through the cable holes 332.
Guide surfaces 333 narrowing downward may be formed on the underside of the lower holder 330 to guide the flow of air. That is, the guide surfaces 333 are narrow at the lower ends, such that the air flowing from below can be guided to quickly flow upward without stopping.
As a result, according to the present invention, since the heat dissipation fins are implemented by one thin metal plate made of one material, it is possible to easily manufacture the heat dissipater, reduce the weight, and improve heat transfer performance. Further, as the sub-heat dissipation fins are further provided, the area coming in contact with air increases, such that the cooling performance can be further improved, and the heat dissipater 100 can function as a main body simultaneously with cooling, such that it is possible to simplify the structure of the LED lighting device. Further, as passages through which the heat generated from the heat-generating unit can be discharged together with the external air to the outside are ensured, the discharge speed of heat is high in a device including a heat-generating unit, such that the performance of the device can be improved.
Although the spirit of the bent-type heat dissipater 100 according to the present invention is described above with reference to the accompanying drawings, this is an example for describing the most preferable embodiment of the present invention and does not limit the present invention.
Therefore, it is apparent that the present invention may be modified and copied in dimensions, shape, and structure by those skilled in the art without departing from the scope of the present invention and those modifications and copies are included in the scope of the present invention.

Claims

1. A bent-type heat dissipater comprising:

a heat dissipation plate having one or a plurality of cooling holes that form passages to discharge heat, which transfers in one direction, together with external air in the opposite direction; and

one or a plurality of heat dissipation fins integrally bending from the heat dissipation plate.

2. The bent-type heat dissipater of claim 1, wherein the cooling hole is formed at the center of the heat dissipation plate.

3. The bent-type heat dissipater of claim of claim 1, wherein the cooling hole is shaped in any one of a circle, an ellipse, and a polygon.

4. The bent-type heat dissipater of claim 1, wherein the inner diameter of the cooling hole is 6.5 to 80% of the outer diameter of the heat dissipation plate.

5. The bent-type heat dissipater of claim 1, wherein the cooling hole further has a plurality of sub-cooling grooves along the inner circumference.

6. The bent-type heat dissipater of claim 1, wherein the heat dissipation fins are integrally bent up along the edge of the heat dissipation plate and have a predetermined length upward.

7. The bent-type heat dissipater of claim 6, wherein the heat dissipation fins are inclined at a predetermined angle toward the center with respect to the top of the heat dissipation plate.

8. The bent-type heat dissipater of claim 7, wherein the inclination angle of the heat dissipation fins is changed by selectively bending.

9. The bent-type heat dissipater of claim 1, wherein the heat dissipation fins further have one or a plurality of sub-holes to pass heat, which flows inside from the cooling hole, to the outside.

10. The bent-type heat dissipater of claim 1, wherein the heat dissipation fins are formed at regular intervals, and

a plurality of sub-heat dissipation fins is further disposed at the gaps between the heat dissipation fins, along the regular edge of the heat dissipation plate in order to increase a heat dissipation area.

11. The bent-type heat dissipater of claim 10, wherein the sub-heat dissipation fins are formed in any one of a shape bent in one direction to have a plurality of steps and a zigzag shape alternately bent in two directions to have a plurality of steps.