U.S. patent application number 13/224323 was filed with the patent office on 2012-03-08 for fan and manufacturing method thereof.
This patent application is currently assigned to DELTA ELECTRONICS, INC.. Invention is credited to Chiu-Kung Chen, Bing-Feng Wang, Chun-Chih Wang.
Application Number | 20120057966 13/224323 |
Document ID | / |
Family ID | 45770860 |
Filed Date | 2012-03-08 |
United States Patent
Application |
20120057966 |
Kind Code |
A1 |
Chen; Chiu-Kung ; et
al. |
March 8, 2012 |
FAN AND MANUFACTURING METHOD THEREOF
Abstract
A fan includes a motor base, a bearing, an impeller, a stator
and a magnetic element. The motor base has a bearing stand in a
center portion thereof. The bearing is accommodated within the
bearing stand. The impeller includes a metallic case, a hub, plural
blades and a rotating shaft. The metallic case has a top surface
and a sidewall. The hub is sheathed around the metallic case. The
blades are disposed around an outer periphery of the hub. The
rotating shaft is protruded from a center portion of the top
surface and penetrated through the bearing stand, wherein no raised
ring structure is formed in the top surface of the metallic case,
and the rotating shaft and the metallic case are jointed together
by a laser welding process. The magnetic element is disposed on an
inner wall of the metallic case and aligned with the stator.
Inventors: |
Chen; Chiu-Kung; (Taoyuan
Hsien, TW) ; Wang; Chun-Chih; (Taoyuan Hsien, TW)
; Wang; Bing-Feng; (Taoyuan Hsien, TW) |
Assignee: |
DELTA ELECTRONICS, INC.
|
Family ID: |
45770860 |
Appl. No.: |
13/224323 |
Filed: |
September 1, 2011 |
Current U.S.
Class: |
415/170.1 ;
29/889 |
Current CPC
Class: |
F04D 29/281 20130101;
Y10T 29/49316 20150115 |
Class at
Publication: |
415/170.1 ;
29/889 |
International
Class: |
F01D 25/16 20060101
F01D025/16; B21D 53/78 20060101 B21D053/78 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 3, 2010 |
TW |
099129810 |
Claims
1. A fan, comprising: a motor base having a bearing stand in a
center portion thereof; a bearing accommodated within said bearing
stand; an impeller comprising: a metallic case having a top surface
and a sidewall extended axially from an outer periphery of said top
surface; a hub sheathed around said metallic case; plural blades
disposed around an outer periphery of said hub; and a rotating
shaft protruded from a center portion of said top surface and
penetrated through said bearing stand, wherein no raised ring
structure is formed in said top surface of said metallic case, and
said rotating shaft and said metallic case are jointed together by
a laser welding process; a stator disposed around an outer
periphery of said bearing stand; and a magnetic element disposed on
an inner wall of said metallic case and aligned with said
stator.
2. The fan according to claim 1 wherein said top surface of said
metallic case has a thickness of 0.1.about.2.0 mm.
3. The fan according to claim 1 wherein an opening is formed in
said center portion of said top surface of said metallic case, and
said rotating shaft is inserted into said opening.
4. The fan according to claim 1 wherein said rotating shaft is made
of metallic shaft.
5. The fan according to claim 1 wherein no embossed recess is
formed in said rotating shaft.
6. The fan according to claim 1 wherein said blades are integrally
formed with said hub.
7. The fan according to claim 1 wherein said metallic case further
comprises a sub-top surface at a horizontal level lower than said
top surface, wherein when said metallic case is sheathed by said
hub, said sub-top surface of said metallic case is sheltered by
said hub.
8. The fan according to claim 1 wherein said fan further comprises
a fan frame, which is arranged at an outer portion of said fan.
9. The fan according to claim 1 wherein an overall thickness of
said fan is smaller than 10 mm.
10. A fan, comprising: a motor base having a bearing stand in a
center portion thereof; a bearing accommodated within said bearing
stand; an impeller comprising: a metallic case having a top surface
and a sidewall extended axially from an outer periphery of said top
surface; plural blades disposed around an outer periphery of said
metallic case; and a rotating shaft protruded from a center portion
of said top surface and penetrated through said bearing stand,
wherein no raised ring structure is formed in said top surface of
said metallic case, and said rotating shaft and said metallic case
are jointed together by a laser welding process; a stator disposed
around an outer periphery of said bearing stand; and a magnetic
element disposed on an inner wall of said metallic case and aligned
with said stator.
11. The fan according to claim 10 wherein said blades are made of
metallic material.
12. The fan according to claim 11 wherein said blades are
integrally formed with said metallic case.
13. A method for manufacturing a fan, said method comprising steps
of: providing a metallic case having a top surface and a sidewall
extended downwardly from an outer periphery of said top surface;
combining a rotating shaft with said metallic case by a laser
welding process, so that said rotating shaft is protruded from a
center portion of said top surface of said metallic case; placing a
combination of said rotating shaft and said metallic case within a
mold, and producing a hub and plural blades by a plastic injection
molding process, wherein said hub is sheathed around said metallic
case, and said blades are disposed around an outer periphery of
said hub; providing a motor base having a bearing stand in a center
portion thereof, and accommodating a bearing within said bearing
stand, and disposing a stator around an outer periphery of said
bearing stand; and disposing a magnetic element on an inner wall of
said metallic case, and penetrating said rotating shaft through
said bearing such that said magnetic element is aligned with said
stator.
14. The method according to claim 13 wherein said laser welding
process is performed to joint the rotating shaft and said metallic
case by arranging welding points in a ring-shaped profile.
15. The method according to claim 13 wherein said laser welding
process is performed to joint the rotating shaft and said metallic
case by arranging welding points symmetrically.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a fan, and more
particularly to a slim-type fan. The present invention also relates
to a method of manufacturing such a fan.
BACKGROUND OF THE INVENTION
[0002] With rapid development of high-tech industries, various
electronic devices such as computer or servers become essential in
our lives. As known, the heat-dissipating efficacy of the
electronic device influences the operating stability and the use
life of the overall system. For increasing the heat-dissipating
efficacy and the operating stability of the electronic device, a
fan is usually installed within the electronic device or installed
in the ambient environment to cool the electronic device.
Typically, a conventional fan comprises an impeller and a motor.
FIG. 1A is a schematic perspective view illustrating an impeller of
a conventional fan. FIG. 1B is a schematic exploded view
illustrating the impeller of FIG. 1A. FIG. 1C is a schematic
cross-sectional view illustrating the impeller of FIG. 1A. Please
refer to FIGS. 1A, 1B and 1C. The impeller 1 comprises a hub 10,
plural blades 11, a metallic ring 12 and a rotating shaft 13. The
blades 11 are disposed around the outer periphery of the hub 10.
The blades 11 and the hub 10 are integrally formed by a plastic
injection molding process. The metallic ring 12 is disposed on the
inner peripheral of the hub 10. The rotating shaft 13 is protruded
from a center portion of the hub 10.
[0003] For manufacturing the impeller 1, after the metallic ring 12
is placed within a plastic injection mold (not shown) and the
rotating shaft 13 is inserted into the mold, the impeller 1
including the hub 10, the blades 11, the metallic ring 12 and the
rotating shaft 13 is produced by the plastic injection molding
process. For increasing the adhesion between the rotating shaft 13
and the hub 10, the thickness of the hub 10 should be greater than
a minimum thickness. In addition, a raised ring structure 101 is
vertically formed on the center portion of the inner surface of the
hub 10 and extended along the direction of the rotating shaft 13.
The rotating shaft 13 is inserted into the raised ring structure
101. Moreover, plural reinforcing ribs 102 are radially arranged
around the raised ring structure 101. The rotating shaft 13 further
has an embossed recess 131 corresponding to the raised ring
structure 101 in order to further increase the adhesion between the
rotating shaft 13 and the hub 10.
[0004] The conventional impeller, however, still has some
drawbacks. For example, since the thickness of the hub 10 should be
greater than a minimum thickness and the raised ring structure 101
and the reinforcing ribs 102 of the hub 10 are necessary, the
process of producing the mold for the impeller is difficult. In
addition, the overall height of the impeller is too high. Moreover,
since the rotating shaft 13 further has an embossed recess 131 to
increase the adhesion between the rotating shaft 13 and the hub 10,
if a small-sized rotating shaft 13 is used to produce a slim
impeller, it is difficult to produce the embossed recess 131.
[0005] Therefore, there is a need of providing a slim-type fan and
a manufacturing method thereof in order to obviate the drawbacks
encountered from the prior art.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a fan
and a manufacturing method thereof so as to simplify the mold for
the impeller, avoid the problem of abrading the rotating shaft and
simply the process of producing the rotating shaft.
[0007] It is another object of the present invention to provide a
fan and a manufacturing method thereof so as to reduce an overall
thickness of the fan and achieve the slimness of the fan.
[0008] In accordance with an aspect of the present invention, there
is provided a fan. The fan includes a motor base, a bearing, an
impeller, a stator and a magnetic element. The motor base has a
bearing stand in a center portion thereof. The bearing is
accommodated within the bearing stand. The impeller includes a
metallic case, a hub, plural blades and a rotating shaft. The
metallic case has a top surface and a sidewall extended axially
from an outer periphery of the top surface. The hub is sheathed
around the metallic case. The blades are disposed around an outer
periphery of the hub. The rotating shaft is protruded from a center
portion of the top surface and penetrated through the bearing
stand. In addition, no raised ring structure is formed in the top
surface of the metallic case, and the rotating shaft and the
metallic case are jointed together by a laser welding process. The
stator is disposed around an outer periphery of the bearing stand.
The magnetic element is disposed on an inner wall of the metallic
case and aligned with the stator.
[0009] In an embodiment, the top surface of the metallic case has a
thickness of 0.1.about.2.0 mm. No embossed recess is formed in the
rotating shaft. The overall thickness of the fan is smaller than 10
mm.
[0010] In accordance with another aspect of the present invention,
there is provided a fan. The fan includes a motor base, a bearing,
an impeller, a stator and a magnetic element. The motor base has a
bearing stand in a center portion thereof. The bearing is
accommodated within the bearing stand. The impeller includes a
metallic case, plural blades and a rotating shaft. The metallic
case has a top surface and a sidewall extended axially from an
outer periphery of the top surface. The blades are disposed around
an outer periphery of the metallic case. The rotating shaft is
protruded from a center portion of the top surface and penetrated
through the bearing stand. In addition, no raised ring structure is
formed in the top surface of the metallic case, and the rotating
shaft and the metallic case are jointed together by a laser welding
process. The stator is disposed around an outer periphery of the
bearing stand. The magnetic element is disposed on an inner wall of
the metallic case and aligned with the stator.
[0011] In an embodiment, the blades are made of metallic material.
The blades are integrally formed with the metallic case.
[0012] In accordance with a further aspect of the present
invention, there is provided a method for manufacturing a fan. The
method comprises steps of: providing a metallic case having a top
surface and a sidewall extended downwardly from an outer periphery
of the top surface; combining a rotating shaft with the metallic
case by a laser welding process, so that the rotating shaft is
protruded from a center portion of the top surface of the metallic
case; placing a combination of the rotating shaft and the metallic
case within a mold, and producing a hub and plural blades by a
plastic injection molding process, wherein the hub is sheathed
around the metallic case, and the blades are disposed around an
outer periphery of the hub; providing a motor base having a bearing
stand in a center portion thereof, and accommodating a bearing
within the bearing stand, and disposing a stator around an outer
periphery of the bearing stand; and disposing a magnetic element on
an inner wall of the metallic case, and penetrating the rotating
shaft through the bearing such that the magnetic element is aligned
with the stator.
[0013] The above contents of the present invention will become more
readily apparent to those ordinarily skilled in the art after
reviewing the following detailed description and accompanying
drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1A is a schematic perspective view illustrating an
impeller of a conventional fan;
[0015] FIG. 1B is a schematic exploded view illustrating the
impeller of FIG. 1A;
[0016] FIG. 1C is a schematic cross-sectional view illustrating the
impeller of FIG. 1A;
[0017] FIG. 2A is a schematic perspective view illustrating an
impeller of a fan according to an embodiment of the present
invention;
[0018] FIG. 2B is a schematic exploded view illustrating the
impeller of FIG. 2A;
[0019] FIG. 2C is a schematic cross-sectional view illustrating the
impeller of FIG. 2A;
[0020] FIG. 3 is a schematic cross-sectional view illustrating a
fan according to an embodiment of the present invention; and
[0021] FIG. 4 is a schematic cross-sectional view illustrating a
fan according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] The present invention will now be described more
specifically with reference to the following embodiments. It is to
be noted that the following descriptions of preferred embodiments
of this invention are presented herein for purpose of illustration
and description only. It is not intended to be exhaustive or to be
limited to the precise form disclosed.
[0023] FIG. 2A is a schematic perspective view illustrating an
impeller of a fan according to an embodiment of the present
invention. FIG. 2B is a schematic exploded view illustrating the
impeller of FIG. 2A. FIG. 2C is a schematic cross-sectional view
illustrating the impeller of FIG. 2A. Please refer to FIGS. 2A, 2B
and 2C. The impeller 2 comprises a hub 20, plural blades 21, a
metallic case 22 and a rotating shaft 23. The metallic case 22 is
sheathed by the hub 20. The blades 21 are disposed around the outer
periphery of the hub 20. In addition, the blades 21 and the hub 20
are integrally formed by a plastic injection molding process.
[0024] The metallic case 22 has a top surface 221 and a sidewall
222. The sidewall 222 is axially or downwardly extended from the
outer periphery of the top surface 221. The rotating shaft 23 is
made of metallic material, and protruded from a center portion of
the top surface 221. An opening is formed in the center portion of
the top surface 221 of the metallic case 22. After the rotating
shaft 23 is inserted into the opening, the rotating shaft 23 is
combined with the top surface 221 of the metallic case 22 by a
laser welding process. In FIG. 2C, the welding region S is circled
by a dashed line. During the laser welding process is performed,
high power laser beams are projected on the metallic surface to
melt the metallic surface. After the molten metal is cooled, the
rotating shaft 23 and the metallic case 22 are jointed together.
Since the laser welding process has small welding joints, high
precision and centralized energy, the laser welding process is able
to form a secure welded structure through thin-walled parts. Since
the laser welding process may create a strong adhesion between the
rotating shaft 23 and the metallic case 22, the raised ring
structure of the hub and the embossed recess of the rotating shaft
that are used in the conventional impeller may be omitted.
Moreover, since the thickness of the top surface 221 of the
metallic case 22 is too small (e.g. 0.1.about.2.0 mm), it is
advantageous to design a slim-type fan by using the impeller 2. As
the thickness of the metallic case 22 is decreased, the space under
the metallic case 22 for accommodating the stator of the fan will
be increased. In this situation, the coil turn may be increased in
order to enhance the operating performance of the fan.
[0025] For manufacturing the impeller 2, the rotating shaft 23 and
the metallic case 22 are firstly jointed together by the laser
welding process, then the combination of the rotating shaft 23 and
the metallic case 22 is placed within a plastic injection mold (not
shown), and finally the hub 20 and the blades 21 of the impeller 2
are produced by the plastic injection molding process. In
accordance with the present invention, no raised ring structure is
formed in the top surface 221 of the metallic case 22, and no
embossed recess is formed in the rotating shaft 23. In addition,
the thickness of the top surface 221 of the metallic case 22 is
ranged from 0.1 to 2.0 mm.
[0026] Since the rotating shaft 23 and the metallic case 22 are
firstly jointed together by the laser welding process and then the
hub 20 and the blades 21 of the impeller 2 are produced by the
plastic injection molding process, the mold for the impeller 2 of
the present invention is simpler than the mold used in the
conventional impeller. In addition, the adhesion between the
rotating shaft and the hub is not necessarily taken into
consideration, the possibility of abrading the rotating is
minimized, the thicknesses of the hub and the metallic case are not
needed to be greater than the minimum thickness, and the hub and
the metallic case are not shrunk or deformed after the plastic
injection molding process is done. Moreover, since no embossed
recess is formed in the rotating shaft, the process of producing
the rotating shaft is very simple. Since the welding points for
performing the laser welding process are symmetrically arranged or
arranged in a ring-shaped profile, the range of the torsion force
of the rotating shaft will be widened.
[0027] The laser welding process may be performed to weld various
metals. That is, the metallic case 22 and the rotating shaft 23 of
the impeller 2 may be made of any metallic material or alloy, for
example gold, silver, copper, iron, titanium, nickel, tin,
aluminum, chromium, or the alloy thereof. In addition, the metallic
case 22 and the rotating shaft 23 may be made of identical material
or different materials.
[0028] Please refer to FIG. 2C. The outer surface of the metallic
case 22 may has a level difference. That is, the metallic case 22
further comprises a sub-top surface 223, whose horizontal level is
slightly lower than the top surface 221. When the metallic case 22
is sheathed by the hub 20, the sub-top surface 223 of the metallic
case 22 is sheltered by the hub 20, but the top surface 221 of the
metallic case 22 and the hub 20 are substantially at the same
level. As a consequence, the overall height of the fan is not
considerably increased.
[0029] FIG. 3 is a schematic cross-sectional view illustrating a
fan having the impeller of FIGS. 2A-2C according to an embodiment
of the present invention. As shown in FIG. 3, the fan 3 comprises a
hub 30, plural blades 31, a metallic case 32, a rotating shaft 33,
a motor base 34, a bearing 35, a stator 36, a magnetic element 37
and a fan frame 38. The metallic case 32 is sheathed by the hub 30.
The blades 31 are disposed around the outer periphery of the hub
30. In addition, the blades 31 and the hub 30 are integrally formed
by a plastic injection molding process. The metallic case 32 is an
integral part, and comprises a top surface 321 and a sidewall 322.
The sidewall 322 is axially or downwardly extended from the outer
periphery of the top surface 321. The rotating shaft 33 is made of
metallic material, and protruded from a center portion of the top
surface 321. The rotating shaft 33 is combined with the top surface
321 of the metallic case 32 by a laser welding process. A bearing
stand 341 is formed in a center portion of the motor base 34. The
bearing 35 is accommodated within the bearing stand 341. The
rotating shaft 33 is penetrated through the bearing 35. The stator
36 is disposed around the outer periphery of the bearing stand 341.
The magnetic element 37 is disposed on the inner wall of the
metallic case 32 and aligned with the stator 36. The fan frame 38
is disposed at the outer portion of the fan 3 and surrounds the hub
30, the blades 31, the metallic case 32, the rotating shaft 33, the
motor base 34, the bearing 35, the stator 36 and the magnetic
element 37. Since the rotating shaft 33 and the metallic case 32
are jointed together by the laser welding process, the thicknesses
of the metallic case 32 is not needed to be greater than the
minimum thickness. In this situation, the overall thickness H of
the fan 3 may be smaller than 10 mm. Preferably, the overall
thickness H of the fan 3 is smaller than 7 mm. Consequently, this
slim-type fan 3 is achievable and may be used in an ultra-thin
notebook computer or other slim-type electronic device.
[0030] The present invention further provides a method of
manufacturing a fan. Firstly, the rotating shaft 33 and the
metallic case 32 are firstly jointed together by a laser welding
process. Then, the combination of the rotating shaft 33 and the
metallic case 32 is placed within a plastic injection mold (not
shown). Afterward, the hub 30 and the blades 31 of an impeller are
produced by the plastic injection molding process. In accordance
with the present invention, no raised ring structure is formed in
the top surface 321 of the metallic case 32, and no embossed recess
is formed in the rotating shaft 33. In addition, the thickness of
the top surface 321 of the metallic case 32 is ranged from 0.1 to
2.0 mm. Then, a motor base 34 is provided, wherein the motor base
34 has a bearing stand 341 in a center portion thereof. Afterward,
a bearing 35 is accommodated within the bearing stand 341, and a
stator 36 is disposed around the outer periphery of the bearing
stand 341. Then, a magnetic element 37 is disposed on the inner
wall of the metallic case 32. Thereafter, the rotating shaft 33 is
penetrated through the bearing 35 such that the magnetic element 37
is aligned with the stator 36. Then, a fan frame 38 is disposed at
the outer portion of the above resulting structure. Meanwhile, the
fan 3 is assembled.
[0031] FIG. 4 is a schematic cross-sectional view illustrating a
fan according to another embodiment of the present invention. As
shown in FIG. 4, the fan 4 comprises plural blades 41, a metallic
case 42, a rotating shaft 43, a motor base 44, a bearing stand 441,
a bearing 45, a stator 46, a magnetic element 47 and a fan frame
48. In this embodiment, the blades 41 are made of metallic material
rather than plastic material. As a consequence, the blades 41 are
integrally formed with the metallic case 42, and blades 41 are
disposed around the outer periphery of the metallic case 42. In
addition, no hub is included in the fan 4. The configurations of
the other components of the fan 4 are similar to those of the fan 3
as shown in FIG. 3, and are not redundantly described herein. Since
the rotating shaft 43 and the metallic case 42 are jointed together
by the laser welding process, the thicknesses of the metallic case
42 is not needed to be greater than the minimum thickness. In this
situation, the overall thickness H of the fan 4 may be smaller than
10 mm. Preferably, the overall thickness H of the fan 4 is smaller
than 7 mm. Consequently, this slim-type fan 4 is achievable and may
be used in an ultra-thin notebook computer or other slim-type
electronic device
[0032] From the above description, the fan impeller of the present
invention comprises a hub, plural blades, a metallic case and a
rotating shaft. The rotating shaft is protruded from a center
portion of the top surface. The rotating shaft and the metallic
case are directly jointed together by a laser welding process. In
addition, no raised ring structure is formed in the top surface of
the metallic case. In accordance with the present invention, the
top surface of the metallic case has a thickness of 0.1.about.2.0
mm. The problem of abrading the rotating shaft will be eliminated.
In addition, the mold for the impeller is simplified. Since no
embossed recess is formed in the rotating shaft, the range of the
torsion force of the rotating shaft will be widened. Moreover,
since the overall thickness of the fan may be smaller than 10 mm,
the slim-type fan of the present invention may be used in an
ultra-thin notebook computer or other slim-type electronic
device.
[0033] 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 embodiment. 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.
* * * * *