U.S. patent application number 10/876117 was filed with the patent office on 2004-11-18 for heat-dissipated mechanism for outer-rotor type brushless dc fan motor.
Invention is credited to Huang, Shih-Ming, Huang, Wen-Shi.
Application Number | 20040227416 10/876117 |
Document ID | / |
Family ID | 33422347 |
Filed Date | 2004-11-18 |
United States Patent
Application |
20040227416 |
Kind Code |
A1 |
Huang, Shih-Ming ; et
al. |
November 18, 2004 |
Heat-dissipated mechanism for outer-rotor type brushless DC fan
motor
Abstract
An outer-rotor type brushless fan motor is provided, wherein the
outer edge of a stator of the outer-rotor type brushless fan motor
is surrounded in the cup-shaped outer periphery of a rotor case of
a rotor thereof, and the rotor is rotated with respect to the
stator. The outer-rotor type brushless fan motor is characterized
in that at least one projection and a corresponding opening thereof
are formed on a surface of the rotor case, so that the projection
and the corresponding opening thereof are rotated together with the
rotation of the rotor, thereby heat generated by the stator is
dissipated.
Inventors: |
Huang, Shih-Ming; (Hsin Chu,
TW) ; Huang, Wen-Shi; (Taoyuan County, TW) |
Correspondence
Address: |
MARTINE & PENILLA, LLP
710 LAKEWAY DRIVE
SUITE 170
SUNNYVALE
CA
94085
US
|
Family ID: |
33422347 |
Appl. No.: |
10/876117 |
Filed: |
June 23, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10876117 |
Jun 23, 2004 |
|
|
|
10178969 |
Jun 24, 2002 |
|
|
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Current U.S.
Class: |
310/58 |
Current CPC
Class: |
F04D 29/329 20130101;
H02K 1/32 20130101; F04D 25/082 20130101 |
Class at
Publication: |
310/058 |
International
Class: |
H02K 001/32; H02K
009/04 |
Foreign Application Data
Date |
Code |
Application Number |
May 7, 2002 |
TW |
91206441 |
Claims
What is claimed is:
1. An outer-rotor type brushless DC fan motor, wherein a cup-shaped
outer periphery of a rotor case of a rotor of the outer-rotor type
brushless DC fan motor encloses an outer edge of a stator thereof,
a fan hub containing a set of fan blades is provided at the outer
periphery of the rotor case, and the rotor is rotated with respect
to the stator; the outer-rotor type brushless DC fan motor is
characterized in that: at least one projection configured in one of
a trigonal prism shape and a trigonal pyramid shape, and an opening
corresponding to the at least one projection are formed on a
surface of the rotor case, so that the projection and the
corresponding opening thereof are rotated together with the
rotation of the rotor, thereby heat generated by the stator is
dissipated.
2. An outer-rotor type brushless DC fan motor, wherein a cup-shaped
outer periphery of a rotor case of a rotor of the outer-rotor type
brushless DC fan motor encloses an outer edge of a stator thereof,
a fan hub containing a set of fan blades is provided at the outer
periphery of the rotor case, and the rotor is rotated with respect
to the stator; the outer-rotor type brushless DC fan motor is
characterized in that: at least one projection configured in one of
a trigonal prism shape and a trigonal pyramid shape, and an opening
corresponding to the at least one projection are formed on the
rotor case and the hub, so that the projection and the
corresponding opening thereof are rotated together with the
rotation of the rotor, thereby heat generated by the stator is
dissipated.
3. The motor as recited in claim 1, wherein the openings are
positioned alternately relative to the fan blades in the radial
direction of the periphery of the rotor case.
4. The motor as recited in claim 2, wherein the openings are
positioned opposing to the fan blades in the radial direction of
the periphery of the rotor case.
5. The motor as recited in claim 1, wherein the at least one
projection connected to the surface of the rotor case at at least
one side is inwardly configured to have a shape thereof and the
opening.
6. The motor as recited in claim 2, wherein the at least one
projection connected to the surface of the rotor case at at least
one side is inwardly configured to have a shape thereof and the
opening.
7. A heat-dissipated mechanism for outer-rotor type brushless DC
fan motor, wherein a cup-shaped outer periphery of a rotor case of
a rotor of the outer-rotor type brushless fan motor encloses an
outer edge of a stator thereof, a fan hub containing a set of fan
blades is provided at the outer periphery of the rotor case, and
the rotor is rotated with respect to the stator; the
heat-dissipated mechanism is characterized in that: at least one
projection configured in one of a trigonal prism shape and a
trigonal pyramid shape, and an opening corresponding to the at
least one projection are formed on a surface of the rotor case, so
that the projection and the corresponding opening thereof are
rotated together with the rotation of the rotor, thereby heat
generated by the stator is dissipated.
8. A heat-dissipated mechanism for outer-rotor type brushless DC
fan motor, wherein a cup-shaped outer periphery of a rotor case of
a rotor of the outer-rotor type brushless fan motor encloses an
outer edge of a stator thereof, a fan hub containing a set of fan
blades is provided at the outer periphery of the rotor case, and
the rotor is rotated with respect to the stator; the
heat-dissipated mechanism is characterized in that: at least one
projection configured in one of a trigonal prism shape and a
trigonal pyramid shape, and an opening corresponding to the at
least one projection are formed on the rotor case and the hub, so
that the projection and the corresponding opening thereof are
rotated together with the rotation of the rotor, thereby heat
generated by the stator is dissipated.
9. The heat-dissipated mechanism as recited in claim 7, wherein the
openings are positioned alternately relative to the fan blades in
the radial direction of the periphery of the rotor case.
10. The heat-dissipated mechanism as recited in claim 8, wherein
the openings are positioned opposing to the fan blades in the
radial direction of the periphery of the rotor case.
11. The heat-dissipated mechanism as recited in claim 7, wherein
the at least one projection connected to the surface of the rotor
case at at least one side is inwardly configured to have a shape
thereof and the opening.
12. The heat-dissipated mechanism as recited in claim 8, wherein
the at least one projection connected to the surface of the rotor
case at at least one side is inwardly configured to have a shape
thereof and the opening.
Description
CLAIM OF PRIORITY
[0001] This Application is a continuation-in-part of and claims
priority under 35 U.S.C. .sctn. 120 of U.S. application Ser. No.
10/178,969, filed on Jun. 24, 2002. This application is hereby
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an outer-rotor type
brushless fan motor, and more particularly, to an outer-rotor type
brushless DC fan motor with forced-ventilation mechanism.
[0004] 2. Description of the Related Art
[0005] Please refer to FIG. 1, a partially cross sectional view of
a conventional outer-rotor type brushless DC fan motor 100 is
illustrated.
[0006] As shown in FIG. 1, the conventional outer-rotor type
brushless DC fan motor 100 comprises a rotor 101, a bearing
assembly 201, a stator 301 and a plate 401. The rotor 101 is
constituted by a shaft 102, a rotor case 104, a fan hub 103, and a
permanent magnet 105 provided on an inner surface of a cup-shaped
outer periphery of the rotor case 104. The bearing assembly 201
comprises at least one bearing 202 and a bearing housing 203,
wherein the at least one bearing 202 is provided between the shaft
102 and an inner surface of the bearing housing 203. The stator 301
includes a plurality of silicon steel sheets 302 radially fixed to
an outer surface of the bearing housing 203 and a set of coils 303
wound around each silicon steel sheet 302, wherein the cup-shaped
outer periphery of the rotor case 104 encloses an outer edge of the
stator 301, and the rotor 101 is rotated with respect to the stator
301. Furthermore, the plate 401 is fixed to the bearing housing 203
so as to support the outer-rotor type brushless DC fan motor
100.
[0007] However, when the conventional outer-rotor type brushless DC
fan motor 100 runs, heat generated from the stator 301 enclosed in
the DC fan motor 100 can not be dissipated effectively, resulting
in the rated temperature of the running DC fan motor 100 being
unable to reduce, and then the efficiency of the DC fan motor 100
being deteriorated at high temperature.
[0008] In view of the above, it is required an outer-rotor type
brushless fan motor capable of reducing the temperature resulted
from the running thereof and increasing the efficiency thereof.
SUMMARY OF THE INVENTION
[0009] Thus, it is an object of the present invention to provide an
outer-rotor type brushless DC fan motor capable of reducing the
temperature resulted from the running thereof and increasing the
efficiency thereof.
[0010] The outer-rotor type brushless fan motor is provided
according to one embodiment of the present invention, wherein a
cup-shaped outer periphery of a rotor case of a rotor of the
outer-rotor type brushless DC fan motor encloses an outer edge of a
stator thereof, and the rotor is rotated with respect to the
stator; the outer-rotor type brushless DC fan motor is
characterized in that: at least one projection and an opening
corresponding to the at least one projection are formed on a
surface of the rotor case, so that the projection and the
corresponding opening thereof are rotated together with the
rotation of the rotor, thereby heat generated by the stator is
dissipated.
[0011] It is preferred that the at least one projection connected
to the surface of the rotor case at at least one side is inwardly
configured to have a shape thereof and the opening.
[0012] A heat-dissipated mechanism for an outer-rotor type
brushless DC fan motor is provided according to another embodiment
of the present invention, wherein a cup-shaped outer periphery of a
rotor case of a rotor of the outer-rotor type brushless DC fan
motor encloses an outer edge of a stator thereof, and the rotor is
rotated with respect to the stator; the heat-dissipated mechanism
is characterized in that: at least one projection and an opening
corresponding to the at least one projection are formed on a
surface of the rotor case, so that the projection and the
corresponding opening thereof are rotated together with the
rotation of the rotor, thereby heat generated by the stator is
dissipated.
[0013] It is preferred that the at least one projection connected
to the surface of the rotor case at at least one side thereof is
inwardly configured to have a shape thereof and the opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 illustrates a partially cross sectional view of the
conventional outer-rotor type brushless DC fan motor.
[0015] FIG. 2A illustrates a partially cross sectional view of the
outer-rotor type brushless DC fan motor according to an embodiment
of the present invention.
[0016] FIG. 2B illustrates a partially cross sectional view of the
outer-rotor type brushless DC fan motor according to an embodiment
of the present invention.
[0017] FIGS. 3A to 3C illustrate side views of the modified
projections and openings viewed along the lateral direction in
FIGS. 2A and 2B.
[0018] FIG. 4A illustrates a cross sectional view of the projection
and opening according to another modification of FIGS. 2A and
2B.
[0019] FIG. 4B illustrates a side view of the projection and
opening viewed along the lateral direction in FIG. 4A.
[0020] FIG. 4C illustrates the projection and opening of FIG. 4
viewed from top of the rotor case 14.
[0021] FIG. 5A illustrates a cross sectional view of the projection
and opening according to still another modification of FIGS. 2A and
2B.
[0022] FIG. 5B illustrates a side view of the projection and
opening viewed along the lateral direction in FIG. 5A.
[0023] FIG. 5C illustrates the projection and opening of FIG. 5
viewed from top of the rotor case 14.
[0024] FIG. 6 illustrates a side view of the heat-dissipated
mechanism of the outer-rotor type brushless DC fan motor according
to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] Please refer to FIG. 2A, a partially cross sectional view of
an outer-rotor type brushless DC fan motor 10 according to an
embodiment of the present invention is illustrated.
[0026] As shown in FIG. 2A, the outer-rotor type brushless DC motor
10 also comprises a rotor 11, a bearing assembly 21, a stator 31
and a plate 41. The rotor 11 is constituted by a shaft 12, a rotor
case 14, a fan hub 13, and a permanent magnet 15 provided on an
inner surface of a cup-shaped outer periphery of the rotor case 14.
The fan hub 13 includes a set of fan blades 13a. The bearing
assembly 21 comprises at least one bearing 22 and a bearing housing
23, wherein the at least one bearing 22 is provided between the
shaft 12 and an inner surface of the bearing housing 23. The stator
31 includes a plurality of silicon steel sheets 32 radially fixed
to an outer surface of the bearing housing 23 and a set of coils 33
wound around each silicon steel sheet 32, wherein the cup-shaped
outer periphery of the rotor case 14 encloses an outer edge of the
stator 31, and the rotor 11 is rotated with respect to the stator
31. Furthermore, the plate 41 is fixed to the bearing housing 23 so
as to support the outer-rotor type brushless DC motor 10.
[0027] Specifically, as shown in FIG. 2A, the outer-rotor type
brushless DC fan motor 10 is characterized in that at least one
projection 16 and a corresponding opening 17 thereof are formed on
a surface of the rotor case 14, so that the projection 16 and the
corresponding opening 17 thereof are rotated together with the
rotation of the rotor 11, thereby heat generated from the stator 31
is dissipated. The openings 17 are positioned alternately relative
to the fan blades 13a in the radial direction of the periphery of
the rotor case.
[0028] FIG. 2B shows another embodiment of the present invention
where the configuration is the same as that shown in FIG. 2A except
that the fan hub 13 without the corresponding openings does not
cover the openings 17, which are positioned opposing to the fan
blades 13a in the radial direction of the periphery of the rotor
case.
[0029] Please refer to FIGS. 3A to 3C, illustrating side views of
the modified projections and openings viewed along the lateral
direction in FIGS. 2A and 2B.
[0030] As shown in FIG. 3A, the projection 16 is formed such that
one end of the projection 16 is connected to the surface of the
rotor case 14 and the other end is inwardly folded to have a slope
and the opening 17 is thus formed correspondingly. Preferably, the
projection 16 and opening 17 are configured by means of stamping.
Therefore, the projection 16 and opening 17 function like fan
blades while both of them are rotated together with the rotation of
the rotor 11, thereby an air flow caused by the forced ventilation
is occurred in the outer-rotor type brushless DC fan motor 10, so
that it is possible to dissipate the heat generated from the stator
31, resulting in effective reduction of the rated temperature of
the running motor 10 effectively and the increase of the efficiency
of the motor 10.
[0031] As shown in FIG. 3B, a modification of the projection 16 and
opening 17 in FIG. 3A is illustrated, wherein the slope of the
projection 16' becomes perpendicular to the surface of the rotor
case 14, and an opening 17' is thus formed on the surface of the
rotor case 14 correspondingly.
[0032] As shown in FIG. 3C, another modification of the projection
16 and opening 17 in FIG. 3A is illustrated, wherein the end of a
projection 16" disconnected from the surface of the rotor case 14
forms a surface that is substantially parallel to the surface of
the rotor case 14, and an opening 17" is thus formed on the surface
of the rotor case 14 correspondingly.
[0033] Please refer to FIGS. 4A and 4B, a projection 16'" and
opening 17'" according to another modification of FIGS. 2A and 2B
are illustrated. FIG. 4B illustrates a side view of the projection
16'" and opening 17'" viewed along the lateral direction in FIG.
4A. FIG. 4C further shows the projection 16'" and opening 17'" from
top of the rotor case 14. As shown in FIG. 4C, the rotor case 14 at
areas A and C are cut except for the sides of the areas A and C
connected to area B (the cut-out sides of the areas A and C are
shown in dashed lines) and folded inwardly to form the projection
16'" with trignoal prism shape and the opening 17'" is thus formed
on the areas A and C. As shown in FIGS. 4A and 4B, the projection
16'" connected to the surface of the rotor case 14 at two sides is
inwardly configured to have a trigonal prism shape thereof and the
opening 17'". Preferably, the projection 16'" and opening 17'" are
configured by means of stamping.
[0034] Please refer to FIGS. 5A and 5B, a projection 16"" and
opening 17"" according to still another modification of FIGS. 2A
and 2B are illustrated. FIG. 5B illustrates a side view of the
projection 16"" and opening 17"" viewed along the lateral direction
in FIG. 5A. FIG. 5C further shows the projection 16"" and opening
17"" from top of the rotor case 14. As shown in FIG. 5C, the rotor
case 14 at areas A', B', and C' are cut except for the sides of the
areas A', B', and C' connected to area D (the cut sides of the
areas A', B', and C' are shown in dashed lines) and folded inwardly
to form the projection 16"" with trignoal prism shape and the
opening 17"" is thus formed on the areas A', B', and C'. As shown
in FIGS. 5A and 5B, the projection 16"" disconnected to the surface
of the rotor case 14 merely at one side is inwardly configured to
have a trigonal pyramid shape thereof and the opening 17"".
Preferably, the projection 16"" and opening 17"" are configured by
means of stamping.
[0035] It is to be appreciated that one of ordinary skill in the
art can change or modify the embodiment or the modifications
without departing from the spirit of the present invention. For
example, FIG. 6 illustrates the heat-dissipated mechanism of the
outer-rotor type brushless DC fan motor 10 according to another
embodiment of the present invention, wherein a projection 16'""
connected to the surface of the rotor case 14 at one side is
outwardly configured to have a shape thereof and an opening 17'"".
Further, the modifications of FIG. 6 can be accomplished easily by
persons skilled in the art by referring to FIGS. 3A to 3C, 4A and
5A.
[0036] Although the foregoing invention has been described in some
detail for purposes of clarity of understanding, it will be
apparent that certain changes and modifications may be practiced
within the scope of the appended claims. Accordingly, the present
embodiments are to be considered as illustrative and not
restrictive, and the invention is not to be limited to the details
given herein, but may be modified within the scope and equivalents
of the appended claims.
* * * * *