U.S. patent application number 12/635833 was filed with the patent office on 2010-11-04 for cooling device for illumination source.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to CHUN-YU LIN.
Application Number | 20100276118 12/635833 |
Document ID | / |
Family ID | 43019049 |
Filed Date | 2010-11-04 |
United States Patent
Application |
20100276118 |
Kind Code |
A1 |
LIN; CHUN-YU |
November 4, 2010 |
COOLING DEVICE FOR ILLUMINATION SOURCE
Abstract
An exemplary cooling device includes a hollow cylinder and a
number of fins. The hollow cylinder has a top end and an opposite
bottom end. The fins are evenly distributed on an outer
circumferentila surface of the hollow cylinder along radial
directions. Each of the fins includes a first portion, a middle
portion, and a second portion. A radial width of each fin measured
along a direction perpendicular to a center axis of the hollow
cylinder gradually decreases along each of the first and second
portions toward the middle portion.
Inventors: |
LIN; CHUN-YU; (Tu-Cheng,
TW) |
Correspondence
Address: |
Altis Law Group, Inc.;ATTN: Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
Tu-Cheng
TW
|
Family ID: |
43019049 |
Appl. No.: |
12/635833 |
Filed: |
December 11, 2009 |
Current U.S.
Class: |
165/104.26 ;
165/185 |
Current CPC
Class: |
F21Y 2115/10 20160801;
F21V 29/773 20150115; F21V 29/713 20150115 |
Class at
Publication: |
165/104.26 ;
165/185 |
International
Class: |
F28D 15/04 20060101
F28D015/04; F28F 1/14 20060101 F28F001/14 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 29, 2009 |
CN |
200910301956.4 |
Claims
1. A cooling device comprising: a hollow cylinder comprising a top
end and an opposite bottom end; and a plurality of fins evenly
distributed on an outer circumferential surface of the hollow
cylinder along radial directions; each of the fins comprising a
first portion, a second portion, and a middle portion between the
first and second portions; a radial width of each fin measured
along a direction perpendicular to a center axis of the hollow
cylinder gradually decreasing along each of the first and second
portions toward the middle portion.
2. The cooling device of claim 1, wherein the radial width of each
fin decreases according to a geometric progression along each of
the first and second portions toward the middle portion.
3. The cooling device of claim 1, wherein the radial width of the
each fin has at least one of the following characteristics: the
radial width decreases according to a linear progression along the
first portion toward the middle portion, and the radial width
decreases according to a linear progression along the second
portion toward the middle portion.
4. The cooling device of claim 1, wherein the radial width of each
fin decreases according to a linear progression along each of the
first and second portions toward the middle portion.
5. The cooling device of claim 1, wherein a bottom inner side of
the second portion of each fin defines a cutout, a top of the
cutout is bounded by an edge of the fin, the edge of the fin is
substantially coplanar with the bottom end of the hollow cylinder,
and the cutouts of the fins cooperatively define a receiving space
for receiving at least one light emitting diode (LED) therein.
6. The cooling device of claim 1, further comprising a plurality of
heat pipes, each of the heat pipes comprising an evaporating end
mounted to the second portions of two corresponding of the fins and
an opposite condensing end mounted to the first portions of said
two corresponding of the fins.
7. The cooling device of claim 6, further comprising a circular
flange mounted on end surfaces of the second portions of the fins
and connected to the evaporating ends of the heat pipes.
8. A cooling device comprising: a hollow cylinder comprising a top
end and an opposite bottom end; and a plurality of fins evenly
distributed on an outer circumferential surface of the hollow
cylinder along radial directions; each of the fins comprising a
first portion, a second portion, and a middle portion between the
first and second portions; an outer edge of each of the fins
converging from a top end of the first portion and a bottom end of
the second portion toward the middle portion where the outer edge
is nearest to a center axis of the hollow cylinder.
9. The cooling device of claim 8, wherein the outer edge of each
fin converges from the first and second portions toward the middle
portion according to a geometric progression.
10. The cooling device of claim 8, wherein a radial width of each
fin has at least one of the following characteristics: the radial
width decreases according to a linear progression from the first
portion toward the middle portion, and the radial width decreases
according to a linear progression along the second portion toward
the middle portion.
11. The cooling device of claim 8, wherein a radial width of the
each fin decreases according to a linear progression along each of
the first and second portions toward the middle portion.
12. The cooling device of claim 8, wherein a bottom inner side the
second portion of each fin defines a cutout, a top of the cutout is
bounded by an edge of the fin, the edge of the fin is substantially
coplanar with the bottom end of the hollow cylinder, and the
cutouts of the fins cooperatively define a receiving space for
receiving at least one light emitting diode (LED) therein.
13. The cooling device of claim 8, further comprising a plurality
of heat pipes, each of the heat pipes comprising an evaporating end
mounted to the second portions of two corresponding of the fins and
an opposite condensing end mounted to the first portions of said
two corresponding of the fins.
14. The cooling device of claim 13, further comprising a circular
flange mounted on end surfaces of the second portions of the fins
and connected to the evaporating ends of the heat pipes.
15. A cooling device comprising: a hollow cylinder comprising a top
end and an opposite bottom end; and a plurality of fins equally
angularly distributed on an outer circumferential surface of the
hollow cylinder along radial directions; wherein the fins
cooperatively define an hourglass-shaped heat sink around the
hollow cylinder.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The disclosure relates to cooling devices, and more
particularly, to a cooling device for an illumination source such
as a light emitting diode (LED).
[0003] 2. Description of Related Art
[0004] Light emitting diodes (LEDs) have been widely used as
illumination sources due to their high brightness, long lifespan,
and so on. However, an LED generates a great amount of heat during
operation. When an LED operates continuously for an extended period
of time, the heat generated may build up and diminish the light
output efficiency of the LED. This excessive heat may also shorten
the lifespan of the LED. Accordingly, proper and timely dissipation
of the generated heat is important.
[0005] What is needed is to provide a cooling device for an
illumination source which can avoid excessive buildup of heat and
improve the lifespan of the illumination source.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is an isometric view of a cooling device according to
a first exemplary embodiment.
[0007] FIG. 2 is an isometric view of the cooling device of FIG. 1,
but showing the cooling device inverted.
[0008] FIG. 3 is an isometric view of a cooling device according to
a second exemplary embodiment.
DETAILED DESCRIPTION
[0009] Referring to FIG. 1, a cooling device 100 of a first
exemplary embodiment is shown. The cooling device 100 is for an
illumination source; and includes a hollow cylinder 110, a number
of heat fins 120 evenly distributed on an outer circumferential
surface of the hollow cylinder 110 along radial directions, and a
number of heat pipes 130 mounted on the heat fins 120.
[0010] The hollow cylinder 110 includes a top end 112 and an
opposite bottom end 114. The hollow cylinder 110 is configured for
supporting one or more LEDs on the top end 112 thereof, and is made
of thermally conductive material for transmitting (conducting) heat
generated by the LEDs to the heat fins 120.
[0011] Referring also to FIG. 2, the heat fins 120 are made of good
thermally conductive material such as copper, iron, aluminum alloy
or the like, and are used to dissipate heat to ambient air. Each of
the heat fins 120 includes a first portion 122, an opposite second
portion 124, and a middle portion 126 between the first portion 122
and the second portion 124. An end surface of the first portion 122
of each fin 120 and the top end 112 of the hollow cylinder 110 lie
in a same plane. The second portion 124 of each fin 120 defines a
cutout 124a, which is located at an inner side of the second
portion 124. A top of the cutout 124a is bounded by a bottom 124b
of the fin 120, with the bottom 124b being coplanar with the bottom
end 114 of the hollow cylinder 110. Thus an inmost top extremity of
the cutout 124a is located at the bottom end 114 of the hollow
cylinder 110. The cutouts 124 cooperatively form a receiving space
123 for receiving LEDs therein. A width of each fin 120 measured
along a direction perpendicular to a center axis of the hollow
cylinder 110 gradually decreases along each of the first and second
portions 122, 124 toward the middle portion 126. Such width is
hereinafter referred to as a "radial width." All of the fins 120
cooperatively form a generally hourglass-shaped heat sink around
the hollow cylinder 110.
[0012] In the illustrated embodiment, the radial width of each fin
120 decreases according to a same nonlinear progression along each
of the first and second portions 122, 124 toward the middle portion
126. Thus, the first and second portions 122, 124 each have curved
edges. The nonlinear progression can for example be a geometric
progression. In another example, the edges of the first and second
portions 122, 124 may be arc-shaped. Thereby, each fin 120 has a
generally V-shaped outer profile, with the two sides of the V-shape
converging to a middle of the V-shape. Thus the fins 120
cooperatively form two converging V-shaped profiles at opposite
sides of the cooling device 100 when the cooling device 100 is
viewed from a side thereof, with the two converging V-shaped
profiles being symmetrical to each other. The converging V-shaped
profiles of the fins 120 simplify the fabrication of the fins 120.
In addition, the converging V-shaped profiles provide the fins 120
with increased surface area exposed to ambient air, and enhance the
efficiency of convection of ambient air in direct contact with the
fins 120. Similarly, the converging V-shaped profiles also enhance
the forced convection of such ambient air, for example when a fan
(not shown) blows such ambient air.
[0013] A circular flange 140 is mounted on end surfaces of the
second portions 124 of the fins 120, for supporting and fixing in
position corresponding ends of the heat pipes 130.
[0014] The heat pipes 130 are used as a heat transfer mechanism
that can transport large amounts of heat with a very small
difference in temperature between a hotter interface and a colder
interface. Each of the heat pipes 130 includes an evaporating end
132 and a condensing end 134. The evaporating end 132 of each heat
pipe 130 is mounted on the flange 140 and is in contact with the
second portions 124 of two corresponding adjacent fins 120. The
condensing end 134 of each heat pipe 130 is mounted to top ends of
the first portions 122 of the two corresponding adjacent fins
120.
[0015] In typical use of the cooling device 100, LEDs are received
in the receiving space 123. Heat generated by the LEDs is
transferred to the fins 120 through the hollow cylinder 110, and
quickly dissipated from the fins 120 to ambient air. One reason for
the efficient dissipation is that the converging V-shaped profiles
of the fins 120 can reduce the wind resistance of airflow, thereby
increasing the circulation of ambient air. In addition, the heat
pipes 130 transfer heat from the second portions 124 to the first
portions 122, thereby enhancing heat dissipation and cooling the
second portions 124. The converging V-shaped profiles of the fins
120 of the so-called sandglass-like cooling device 100 can help
cool the LEDs and thereby increase the lifespan of the LEDs.
[0016] Referring to FIG. 3, a cooling of a second exemplary
embodiment is present shown. The cooling device 200 is similar to
the cooling device 100 in most respects. Therefore similar labels
in FIGS. 1 and 3 indicate similar parts of the cooling devices 100
and 200. The cooling device 200 includes a hollow cylinder 210, a
number of heat fins 220 evenly distributed on an outer
circumferential surface of the hollow cylinder 210 along radial
directions, a number of heat pipes 230 mounted on the heat fins
220, and a circular flange 240 mounted on bottom ends of the fins
220. The flange 240 is for supporting and fixing in position bottom
ends of the heat pipes 230. The difference between the cooling
devices 200 and 100 is that the radial width of each fin 220
decreases according to a linear progression along each of a first
portion 222 and a second portion 224 to a middle portion 226. That
is, both the first and the second portions 222, 224 have straight,
oblique edges. In alternative embodiments, the radial width of each
fin 220 decreases according to a linear progression along only one
of the first portion 222 and the second portion 224 to the middle
portion 226.
[0017] It is believed that the present embodiments and their
advantages will be understood from the foregoing description, and
it will be apparent that various changes may be made thereto
without departing from the spirit and scope of the disclosure or
sacrificing all of its material advantages, the examples
hereinbefore described merely being preferred or exemplary
embodiments of the disclosure.
* * * * *