U.S. patent application number 11/812400 was filed with the patent office on 2008-11-20 for cooling device.
This patent application is currently assigned to Sunonwealth Electric Machine Industry Co., Ltd.. Invention is credited to Alex Horng, Shih-Chang Hsu, Pen-Wen Lo.
Application Number | 20080283216 11/812400 |
Document ID | / |
Family ID | 40026335 |
Filed Date | 2008-11-20 |
United States Patent
Application |
20080283216 |
Kind Code |
A1 |
Horng; Alex ; et
al. |
November 20, 2008 |
Cooling device
Abstract
The present invention relates to a cooling structure for motor
of fan, which includes a housing, an impeller and a circuit board.
The housing has an air flow channel and a base; the base is located
on one side of the air flow channel to support the circuit board,
and the impeller is movably integrated on the base; the circuit
board is bonded with a highly heat-conductive metal on at least one
side thereof so as to provide good heat dissipation and heat
transfer performance; at least one portion of the circuit board is
extended beyond the hub of the impeller such that the extended
portion is located at a downwind place of the blades of the
impeller to facilitate fast heat dissipation.
Inventors: |
Horng; Alex; (Kaohsiung
City, TW) ; Hsu; Shih-Chang; (Kaohsiung City, TW)
; Lo; Pen-Wen; (Kaohsiung City, TW) |
Correspondence
Address: |
BACON & THOMAS, PLLC
625 SLATERS LANE, FOURTH FLOOR
ALEXANDRIA
VA
22314-1176
US
|
Assignee: |
Sunonwealth Electric Machine
Industry Co., Ltd.
Kaohsiung City
TW
|
Family ID: |
40026335 |
Appl. No.: |
11/812400 |
Filed: |
June 19, 2007 |
Current U.S.
Class: |
165/47 |
Current CPC
Class: |
F04D 25/0633 20130101;
F04D 25/068 20130101; F04D 29/5813 20130101 |
Class at
Publication: |
165/47 |
International
Class: |
F24F 7/007 20060101
F24F007/007 |
Foreign Application Data
Date |
Code |
Application Number |
May 14, 2007 |
TW |
096117087 |
Claims
1. A cooling structure for motor of fan, comprising: a housing
having an air inlet, an air flow channel, an air outlet and a base,
wherein said air inlet and said air outlet are located on both
sides of said air flow channel, and said base is disposed on one
side of said air flow channel; an impeller rotationally integrated
on said base and having a hub and a plurality of blades; and a
circuit board disposed on said base, wherein at least one side
thereof is installed with a highly heat-conductive metal, and at
least one portion thereof is extended beyond said hub of said
impeller, so that said extended portion is located at a downwind
place to facilitate heat dissipation.
2. The cooling structure of claim 1, wherein said circuit board is
selected from one of flexible printed circuit board and regular
printed circuit board.
3. The cooling structure of claim 1, wherein said highly
heat-conductive metal is chosen from one of aluminum and zinc.
4. The cooling structure of claim 1, wherein said circuit board has
a protrusion extended beyond said hub of said impeller and located
at a downwind place of said blades.
5. The cooling structure of claim 4, wherein a plurality of ribs
are provided between said base and an inner wall of said air flow
channel, at least a rib is equipped with a cable slot, and said
protrusion is located above said rib with said cable slot.
6. The cooling structure of claim 1, wherein said circuit board has
a form selected from one of circle, rectangle and sector.
7. The cooling structure of claim 6, wherein said circular circuit
board has a diameter expandable to be greater than that of said
hub.
8. The cooling structure of claim 6, wherein said rectangular and
sector circuit boards have at least one side or at least one corner
extended beyond said hub.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a cooling structure for
motor of fan, and more particularly to a cooling fan that achieves
the object of temperature rise for its heat-generating electronic
components without changing the original mechanism design, to
prolong the operation lifespan of fan.
BACKGROUND OF THE INVENTION
[0002] As shown in FIG. 1 and FIG. 2, a conventional cooling fan
structure includes a housing 1, an impeller 2 and a circuit board
3.
[0003] The housing 1 has an air flow channel 10, an air inlet, an
air outlet, a base 13 and a stator set 14, in which the air flow
channel 10 accommodates the impeller 2 such that air flow is
inputted from the air inlet 11 and outputted from the air outlet
12, the base is located beside the air inlet 12 for carrying the
circuit board 3, and the stator set 14 and is integrated with the
impeller 2.
[0004] The impeller 2 has a hub 21, a spindle 22, several bladed
and an annular magnet 24, in which the spindle 22 is located
centrally within the hub 21 and is movably bundled on the base 13,
and the blades are circularly disposed around the periphery of the
hub 21.
[0005] A sensing component 31 and at least a heat-generating
electronic component 32 are disposed on the circuit board 3 for
controlling alternate excitation of the stator set 14 to impel and
rotate the impeller 2. Air flow is further driven by the blades 23
to flow from the air inlet 11 to the air outlet 12.
[0006] Whereas, the gate current direction of the heat-generating
electronic component 32 is controlled with a metallic/non-metallic
doping material with semi-conductivity. As a result, while the
heat-generating electronic component is operated, its material
certainly consumes partial electrical energy and converts that into
thermal energy. However, structurally, the heat-generating
electronic component 32 is located within the range covered by the
base 13 and the hub 21. Accordingly, the heat-generating electronic
component 32 lacks of an adequate cooling mechanism, easily impacts
on its operational stability due to an excessively high temperature
and even deteriorates the efficacy and lifespan of the cooling
fan.
[0007] Therefore, the inventor of the present invention has
invented a cooling fan as shown in FIG. 3 and FIG. 4 to improve the
shortcoming of the conventional structure. Such cooling fan has a
protrusion 30 extended from the circuit board 3 and beyond the hub
21 of the impeller 2. The heat-generating electronic component 32
is disposed on the protrusion 30 so that one part or the entire
heat-generating electronic component 32 is located at a downwind
place of the blades 23 of the impeller 21, thereby dissipating the
heat of the heat-generating electronic component 32 by virtue of
air flow guided by the blades 23.
[0008] The cooling fan previously developed by the present
invention can surely reduce the temperature rise of the
heat-generating electronic component 32 and prevent from affecting
the overall performance and lifespan of the cooling fan as a result
of high temperature. However, such solution also gives rise to the
issues of the conflict between the blades 23 and the
heat-generating electronic component 32 accruing electrostatic
interference at the same time.
[0009] In original mechanism design of the cooling fan, a minimum
safety distance H is maintained between the bottom edge of the hub
21 of the impeller 2 and the circuit board 3. However, after the
protrusion 3 and the heat-generating electronic component 32 are
extended beyond the hub 21, the distance h between the bottom edge
of the hub 21 of the impeller 2 and the heat-generating electronic
component 32 will be diminished and thus will result in a conflict
between the impeller 2 and the heat-generating electronic component
32 because it is less than the minimum safety distance H. If
intending to prevent the conflict, the original mechanism design of
the cooling fan must be altered. Furthermore, when one part or the
entire heat-generating electronic component 32 is located at a
downwind place of the blades 23, it is equivalent to a situation
directly exposed to an air flow field guided by the blades 23,
making electrostatic charge generated by air collision in the flow
field interfere with the normal operation of the heat-generating
electronic component 32 or even cause malfunction thereof.
SUMMARY OF THE INVENTION
[0010] In view of the foregoing concern, the present invention thus
provides a cooling structure for motor of fan, whose main object
targets at achieving the function of lowering the temperature rise
of a heat-generating electronic component under the premise of no
change of the original mechanism design. The cooling structure has
a highly heat-conductive metal integrated with at least one side of
a circuit board to enhance the heat dissipation area and heat
transfer performance of the circuit board, and at least one part of
the circuit board is protruded beyond a hub of an impeller so as to
position the protrusion at a downwind place of blades of the
impeller to facilitate fast heat dissipation. Consequently, the
present invention can carry out heat dissipation of the entire
circuit board and the heat-generating electronic component by the
heat transfer function of the highly heat-conductive metal to
similarly attain a good cooling mechanism without altering the
original mechanism design.
[0011] A second object of the present invention is to prevent the
heat-generating electronic component from being interfered by
electrostatic charge in the air flow field. The present invention
can carry out heat dissipation of the entire circuit board and the
heat-generating electronic component such that the heat-generating
electronic component on the circuit won't be necessarily exposed in
the air flow field so as to ensure that its normal operation
function won't be interfered due to electrostatic interference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a plane view showing a conventional structure;
[0013] FIG. 2 is a cross-sectional view showing the conventional
structure;
[0014] FIG. 3 is a plane view showing a prior cooling fan developed
by the inventor of the present invention;
[0015] FIG. 4 is a cross-sectional view showing the prior cooling
fan developed by the inventor of the present invention;
[0016] FIG. 5 is a 3D exploded view showing a first preferred
embodiment of the present invention;
[0017] FIG. 6 is a plane view showing the first preferred
embodiment of the present invention;
[0018] FIG. 7 is a cross-sectional view showing the first preferred
embodiment of the present invention;
[0019] FIG. 8 is a plane view showing a second preferred embodiment
of the present invention; and
[0020] FIG. 9 is a cross-sectional view showing the second
preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] To make the object, characteristic and performance of the
present invention more self-explanatory, two preferred embodiments
of the present invention are provided as follows together with the
illustration of the figures.
[0022] As shown in FIG. 5, a first preferred embodiment of the
present invention includes a housing 1, an impeller 2 and a circuit
board 3.
[0023] Together with the reference to FIG. 6 and FIG. 7, the
housing has an air flow channel 10, an air inlet 11, an air outlet
12, a base 13 and a stator set 14. The air flow channel 10 can
accommodate an impeller 2, the air inlet 11 and the air outlet are
located on both sides of the air flow channel 10 such that air flow
is inputted to the air inlet 11 and outputted from the air outlet
12, the base 13 is selectively disposed beside the air outlet 12 or
the air inlet 11 depending on the requirement of actual
heat-dissipation occasion and has a plurality of ribs 130, a shaft
tube 131 and at least a cable gap 133, in which each rib 130 is
connected with the inner wall of the air flow channel 10 of the
base 13 and the housing 1, one rib corresponding to the cable gap
133 is equipped with a cable slot 132 for a power cord of the
circuit board 3 allowing the power cord of the circuit board 3 to
reach out, the shaft tube 131 can be integrally formed or assembled
on the center of the base 13, the stator set and the circuit board
3 are all fixedly disposed on the base 13 to generate alternate
excitation.
[0024] The impeller 2 has a hub 21, a spindle 22, several blades 23
and an annular magnet 24, in which the spindle 22 is located
centrally within the hub 21 and is movably coupled in the shaft
tube 131, the blades 23 are circularly disposed around the
periphery of the hub 21, and the annular magnet 24 is disposed on
the inner wall of the hub 21 to sense the alternate excitation of
the stator set 14 and impel and rotate the impeller 2 so as to
further drive air to flow in the air inlet 11 and flow out the air
outlet 12.
[0025] The circuit board 3 can be selected from a flexible printed
circuit board or a regular printed circuit board, whose one side is
installed with a highly heat-conductive metal, e.g. copper,
aluminum, zinc, and so forth, to increase the cooling area and heat
transfer performance of the circuit board 3. The circuit board 3
has at least a sensing component 31 and at least a heat-generating
electronic component 32 thereon and has at least a protrusion 30
extended beyond the hub 21 of the impeller 2 and located at a
downwind place of the blades, such that air flow guided by the
blades simultaneously dissipate heat generated by the entire
circuit board 3, the sensing component 31 and the heat-generating
component 32.
[0026] Moreover, the protrusion of the circuit board 3 is
preferably designed in the proximity of the cable gap 133, and
after the protrusion 30 is extended outwards in a radial direction,
it is close to or exactly positioned above the rib 130 equipped
with the cable slot 132. On the one hand, air flow driven by the
blades can still dissipate heat generated by the circuit board 3 to
prevent from impacting on the operational stability and the rated
output power of the heat-generating electronic component 32 and
further prolong the operation lifespan of the fan; on the other
hand, when the protrusion 30 is located above the rib 130 equipped
with the cable slot 132, it will facilitate to relatively alleviate
the turbulence and noise generated by the contact of the protrusion
30 and air flow.
[0027] When the protrusion 30 of the circuit board 3 in the present
invention is extended beyond the hub 21, a default minimum safety
distance H maintained between the bottom edge of the hub 21 and the
circuit board is unchanged. As a result, there will be no conflict
generated by the hub 21 or the blades 23, and thus it is
unnecessary to modify the original mechanism design of the present
invention, thereby lowering the afresh development and design cost.
The heat-generating electronic component 32 of the present
invention is located within a range covered by the based 13 and the
hub 21. The highly heat-conductive metal combined with the circuit
board 3 is employed to provide good heat dissipation and heat
transfer performance. Hence, it is unnecessary for the
heat-generating electronic component 32 to be exposed in air flow
field, meaning that the heat-generating electronic component 32 is
free from electrostatic charge that interferes with its normal
operating function.
[0028] As shown in FIG. 8 and FIG. 9, which relate to the second
preferred embodiment of the present invention, the shape of the
circuit board 3 can be selected from one of circle, rectangle,
sector, and so forth; the circle having its two sides incised forms
a quasi-rectangular shape, and at least a portion of the circuit
board 3 is extended beyond the hub 21 of the impeller 2 to position
at least a portion thereof at a downwind place of the blades 23;
for example, the diameter of the circular circuit board can be
enlarged to one greater than that of the hub 21, and rectangular
and sector circuit boards have at least one side or at least one
corner extended beyond the hub 21; the circuit board 3 can be
selected from either a flexible printed circuit board or a regular
printed circuit board and at least one side thereof is bonded with
a highly heat-conductive metal to increase the cooling area and the
heat transfer performance of the circuit board 3.
[0029] As such, the present invention can achieve the object of
lowering temperature rise of the entire circuit board 3 and the
heat-generating electronic component 32 without changing the
original mechanism design, and to reduce the development and design
cost and prolong the operation lifespan of the fan. Meanwhile, the
heat-generating electronic component 32 won't be necessarily
exposed in an air flow field, thereby avoiding the resulting
electrostatic charge to interfere with its normal operation
performance.
[0030] In sum, from the above-mentioned characteristics those
features not only have a novelty among similar products and a
progressiveness but also have an industry utility.
[0031] While the invention has been described in terms of what is
presently considered to be the most practical and preferred
embodiments, it is to be understood that the invention needs not be
limited to the disclosed embodiments. On the contrary, it is
intended to cover various modifications and similar arrangements
included within the spirit and scope of the appended claims, which
are to be accorded with the broadest interpretation so as to
encompass all such modifications and similar structures.
* * * * *