U.S. patent application number 11/946766 was filed with the patent office on 2008-03-27 for fan assembly and impeller thereof.
Invention is credited to Te-Fu CHEN, Wen-Shi Huang, Tsung-Yu Lei, Kuo-Cheng Lin.
Application Number | 20080075598 11/946766 |
Document ID | / |
Family ID | 34806388 |
Filed Date | 2008-03-27 |
United States Patent
Application |
20080075598 |
Kind Code |
A1 |
CHEN; Te-Fu ; et
al. |
March 27, 2008 |
FAN ASSEMBLY AND IMPELLER THEREOF
Abstract
A fan assembly and impeller thereof. The impeller comprises a
hub having an upper surface, an axial sidewall extended along the
axis of the impeller, and a corner connected between the upper
surface and the axial sidewall; and a plurality of blades directly
connected to the upper surface, the corner or the axial sidewall of
the hub to define an air-intake space between an inner edge of the
blades faced to the axis of the impeller and the upper surface of
the hub for allowing the intake airflow to radially flow toward the
blades.
Inventors: |
CHEN; Te-Fu; (Taoyuan Hsien,
TW) ; Lei; Tsung-Yu; (Taoyuan Hsien, TW) ;
Lin; Kuo-Cheng; (Taoyuan Hsien, TW) ; Huang;
Wen-Shi; (Taoyuan Hsien, TW) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
34806388 |
Appl. No.: |
11/946766 |
Filed: |
November 28, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10827285 |
Apr 20, 2004 |
|
|
|
11946766 |
Nov 28, 2007 |
|
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Current U.S.
Class: |
416/179 |
Current CPC
Class: |
F04D 29/283
20130101 |
Class at
Publication: |
416/179 |
International
Class: |
F04D 1/04 20060101
F04D001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 3, 2004 |
TW |
93102369 |
Claims
1. An impeller comprising: a hub having an upper surface, an axial
sidewall extended along the axis of the impeller, and a corner
connected between the upper surface and the axial sidewall; and a
plurality of blades directly connected to the upper surface, the
corner or the axial sidewall of the hub to define an air-intake
space between inner edges of the blades faced to the axis of the
impeller and the upper surface of the hub for allowing an intake
airflow to radially flow toward the blades.
2. The impeller as claimed in claim 1, wherein the blades are
arranged as an annular structure having an outer diameter greater
than that of the hub, and an inner diameter less than or equal to
the outer diameter of the hub.
3. The impeller as claimed in claim 1, wherein each of the blades
has a bottom end extending downward along the axial sidewall and
there is height difference between the bottom end of the blade and
a lower end of the hub.
4. The impeller as claimed in claim 1, wherein the blades are
radially extended and has an outer edge protruded out from the
corner of the hub.
5. The impeller as claimed in claim 1, wherein the blades are
arranged as an annular structure having an outer diameter equal to
or less than that of the hub.
6. The impeller as claimed in claim 1, wherein each blade is only
directly connected to the upper surface and the corner of the hub
and has an outer edge aligned with the axial sidewall of the
hub.
7. The impeller as claimed in claim 1, wherein each blade is only
directly connected to the upper surface of the hub.
8. The impeller as claimed in claim 1, wherein each blade is only
directly connected to the upper surface and the corner of the
hub.
9. The impeller as claimed in claim 1, wherein each blade is only
directly connected to the axial sidewall of the hub.
10. The impeller as claimed in claim 1, wherein each blade is
directly connected to the upper surface, the corner and the axial
sidewall of the hub.
11. The impeller as claimed in claim 1, further comprising an ring
formed on an outer top corner of the blades to connect the blades,
wherein a periphery of the ring is aligned with outer edges of the
blades.
12. The impeller as claimed in claim 1, wherein the hub and the
blades are integrally formed as a single unit.
13. A fan assembly comprising: an impeller comprising: a hub having
an upper surface, an axial sidewall extended along the axis of the
impeller, and a corner connected between the upper surface and the
axial sidewall; and a plurality of blades directly connected to the
upper surface, the corner or the axial sidewall of the hub to
define an air-intake space between inner edges of the blades faced
to the axis of the impeller and the upper surface of the hub for
allowing an intake airflow to radially flow toward the blades; and
a motor mounted within the hub of the impeller for driving the
impeller to rotate.
14. The fan assembly as claimed in claim 13, wherein the blades are
arranged as an annular structure having an outer diameter greater
than that of the hub, and an inner diameter less than or equal to
the outer diameter of the hub.
15. The fan assembly as claimed in claim 13, wherein each of the
blades has a bottom end extending downward along the axial sidewall
and there is height difference between the bottom end of the blade
and a lower end of the hub.
16. The fan assembly as claimed in claim 13, wherein the blades are
radially extended and has an outer edge protruded out from the
corner of the hub.
17. The fan assembly as claimed in claim 13, wherein the blades are
arranged as an annular structure having an outer diameter equal to
or less than that of the hub.
18. The fan assembly as claimed in claim 13, further comprising an
ring formed on an outer top corner of the blades to connect the
blades, wherein a periphery of the ring is aligned with outer edges
of the blades.
19. The fan assembly as claimed in claim 18, wherein the hub, the
blades and the ring are integrally formed as a single unit.
20. The fan assembly as claimed in claim 13, further comprising a
frame for receiving the impeller and the motor therein.
21. The fan assembly as claimed in claim 20, wherein when the
impeller is driven by the motor to rotate, an airflow is axially
suck and axially flow out of the frame.
22. The fan assembly as claimed in claim 13, wherein when the
impeller is driven by the motor to rotate, an airflow is axially
suck and radially flow out.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of co-pending application
Ser. No. 10/827,285, filed on Apr. 20, 2004, and for which priority
is claimed over Application No. 93102369 filed in Taiwan on Feb. 3,
2004 under 35 U.S.C. .sctn. 119; the entire contents of all are
hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present inventions relates to a fan assembly, and in
particular, to a fan and an impeller thereof with higher strength
and better performance.
[0004] 2. Description of the Related Art
[0005] Electronic devices generally produce heat during operation,
and thus a heat-dissipating device or a fan assembly is required to
dissipate the generated heat. Since the demand for heat dissipation
has been increased, fans must offer optimal performance. A
conventional impeller 10a of a fan is shown in FIG. 1A, including a
plurality of blades 21 and a hub 22. The blades 21 encircle the hub
22. The blades 21 are disposed in a frame 20 and connected to the
hub 22 via a connecting portion 24 extending from a bottom of the
hub 22. A gap 23 is formed between the hub 22 and the blades 21,
and above the connecting portion 24.
[0006] As shown in FIG. 1B, airflow enters the gap 23 to contact
the blades 21 and flows in a direction shown by the dotted line
arrows. Due to space limitations imposed by the other elements in
the fan, a conventional way for increasing the rotation speed of
the motor is to increase the height H of the motor or the hub to
approximately the same height as the blades 21. The motor, however,
almost entirely blocks the inlet such that the airflow is unable to
smoothly flow through the gap 23 between the blades 21 and the hub
22. Thus, the contact area between the airflow and the blades 21 is
insufficient. Because the inlet area is reduced, the performance is
also reduced. Furthermore, the conventional fan requires the gap
23, thereby weakening the strength of the impeller.
[0007] As mentioned above, the conventional fan needs to increase
the height of the motor in order to increase power and rotation
speed, but the length of the blades 21 must also be increased to
increase the airflow contact area. The longer the blades 21,
however, the weaker the strength of the impeller, that is, the long
blades 21 are easily deformed.
[0008] Another conventional impeller 10b adds a rib 25 to increase
the strength of the blades 21, as shown in FIGS. 2A and 2B. Each
blade 21 of the impeller 10b is divided into upper and lower
partial blades 21a and 21b. The rib 25 is disposed between the
upper and lower partial blades 21a and 21b and connected to the hub
22. Thus, the blade structure can be strengthened by the rib 25.
The rib 25, however, may interfere with the airflow, which must
travel around the rib 25 to enter the gap 23, thus causing
turbulence. Furthermore, the amount of inflow is reduced due to
insufficient contact area between the airflow and the blade 21. As
a result, the motor is unable to increase the rotation speed.
[0009] Hence, the above method is still unable to satisfy the
demands of both structural stability and fan performance.
SUMMARY OF THE INVENTION
[0010] Therefore, an object of the present invention is to provide
a fan that eliminates the shortcomings described above.
[0011] The present invention provides an impeller comprising a hub
having an upper surface, an axial sidewall extended along the axis
of the impeller, and a corner connected between the upper surface
and the axial sidewall; and a plurality of blades directly
connected to the upper surface, the corner or the axial sidewall of
the hub to define an air-intake space between inner edges of the
blades faced to the axis of the impeller and the upper surface of
the hub for allowing an intake airflow to radially flow toward the
blades.
[0012] Preferably, the blades are arranged as an annular structure
having an outer diameter greater than that of the hub, and an inner
diameter less than or equal to the outer diameter of the hub,
wherein each blade is only directly connected to the axial sidewall
of the hub, or each blade is directly connected to the upper
surface, the corner and the axial sidewall of the hub.
[0013] Preferably, each of the blades has a bottom end extending
downward along the axial sidewall and there is height difference
between the bottom end of the blade and a lower end of the hub.
[0014] Preferably, the blades are radially extended and has an
outer edge protruded out from the corner of the hub.
[0015] Alternatively, the blades are arranged as an annular
structure having an outer diameter equal to or less than that of
the hub, wherein each blade is only directly connected to the upper
surface and the corner of the hub and has an outer edge aligned
with the axial sidewall of the hub, or each blade is only directly
connected to the upper surface of the hub.
[0016] In addition, the impeller further comprises an ring formed
on an outer top corner of the blades to connect the blades, wherein
a periphery of the ring is aligned with outer edges of the
blades.
[0017] Preferably, the hub and the blades are integrally formed as
a single unit.
[0018] Another object of the present invention is to provide a fan
assembly comprising an impeller comprising a hub having an upper
surface, an axial sidewall extended along the axis of the impeller,
and a corner connected between the upper surface and the axial
sidewall; and a plurality of blades directly connected to the upper
surface, the corner or the axial sidewall of the hub to define an
air-intake space between inner edges of the blades faced to the
axis of the impeller and the upper surface of the hub for allowing
an intake airflow to radially flow toward the blades; and a motor
mounted within the hub of the impeller for driving the impeller to
rotate.
[0019] Preferably, the fan assembly further comprises an ring
formed on an outer top corner of the blades to connect the blades,
wherein a periphery of the ring is aligned with outer edges of the
blades, wherein the hub, the blades and the ring are integrally
formed as a single unit.
[0020] In addition, the fan assembly further comprises a frame for
receiving the impeller and the motor therein. When the impeller is
driven by the motor to rotate, an airflow is axially suck and
axially flow out of the frame.
[0021] Alternatively, when the impeller is driven by the motor to
rotate, an airflow is axially suck and radially flow out.
DESCRIPTION OF THE DRAWINGS
[0022] The present invention can be more fully understood by
reading the subsequent detailed description in conjunction with the
examples and references made to the accompanying drawings,
wherein:
[0023] FIG. 1A is a schematic diagram of a conventional
impeller;
[0024] FIG. 1B is a cross section of a conventional fan having the
impeller shown in FIG. 1A;
[0025] FIG. 2A is a schematic diagram of another conventional
impeller;
[0026] FIG. 2B is a cross section of another conventional fan
having the impeller shown in FIG. 2A;
[0027] FIG. 3A is a schematic diagram of a fan assembly of a first
embodiment;
[0028] FIG. 3B is a perspective diagram of an impeller of the first
embodiment shown in FIG. 3A;
[0029] FIG. 3C is a cross section viewed along line AA, of FIG.
3B;
[0030] FIG. 4 is a schematic diagram of an impeller of the second
embodiment according to the present invention;
[0031] FIG. 5 is a schematic diagram of an impeller of the third
embodiment according to the present invention;
[0032] FIG. 6A is a schematic diagram of an impeller of the fourth
embodiment according to the present invention;
[0033] FIG. GB is a cross section along line BB' of FIG. 6A;
[0034] FIG. 7 is a cross section of an impeller of the fifth
embodiment according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
First Embodiment
[0035] FIG. 3A is a schematic diagram of a fan assembly 3 of the
first embodiment. FIGS. 3B and 3C are schematic diagrams of an
impeller 30 of the first embodiment shown in FIG. 3A. The fan
assembly 3 comprises a frame 36, a motor 35, and an impeller 30.
The impeller 30 is disposed in the frame 36 and comprises a hub 32
and a plurality of blades 31. The hub 32 includes an upper surface
321, a lower surface 323, an axial sidewall 322 extended along the
axis of the impeller 30, and a corner 324 connected between the
upper surface 321 and the axial sidewall 322. The motor 35 is
completely mounted within the hub 32 as shown in FIGS. 3A and 3C.
The blades 31 are directly connected to the axial sidewall 322 and
the corner 324, and arranged as an annular structure. The blades 31
and the hub 32 can be integrally formed as a single unit, and there
is no gap therebetween. As a result, the strength of the impeller
30 is improved to prevent blade deformation and warping.
[0036] Furthermore, in the present invention, the motor 35 is
redesigned to match the size of the hub to be completely disposed
within the hub in order to increase air inflow. Unlike the
conventional motor with a thick and compact profile, the present
invention reduces the height H of the motor 35 and increases its
width. Thus, the motor 35 is wide and thin. Although the size is
changed, the performance and power of the motor is preserved.
[0037] As shown in FIG. 3C, the blades 31 are arranged as an
annular structure having an outer diameter D.sub.1. The outer
diameter D.sub.1 is greater than the outer diameter L of the hub
32. In addition, the inner diameter d of the annular structure is
less than the outer diameter L of the hub 32.
[0038] An upper end 31a of the blade 31 is positioned higher than
the upper surface 321 of the hub so that there is an air-intake
space is formed between the inner edge 31c of the blades 31 and the
upper surface 321 of the hub 32 for allowing the intake airflow to
radially flow toward the blades as the dotted line arrows shown in
FIG. 3C.
[0039] Each blade 31 of the impeller 30 has a bottom end 31b
extending downward along the axial sidewall 322. There is a height
difference h between the bottom end 31b of the blade 31 and the
lower end 323 of the hub 32. The axially extended bottom end 31b
increases the total length of each blade 31, thereby increasing the
strength thereof.
[0040] In addition, the impeller 30 further comprises a ring 33
formed on the outer top corner of the blades 31 to connect all
blades as shown in FIGS. 3B and 3C. A periphery of the ring is
aligned with outer edges of the blades 31. The blades 31, the ring
33 and the hub 32 can be integrally formed as a single unit
Second Embodiment
[0041] FIG. 4 shows an impeller 30a of the second embodiment. The
impeller 40 is similar to the first embodiment except that there is
no frame and the blades 31 of the impeller 30a are arranged as an
annular structure with an outer diameter D.sub.1 greater than the
outer diameter L of the hub 32, and an inner diameter d equal to
the outer diameter L of the hub 32. That is, the blade 31 is only
directly connected to the axial sidewall 322 of the hub 32. Thus,
this embodiment can utilize a motor with a larger diameter L.
Accordingly, the blades 31 are axially extended along the sidewall
322, wherein the upper ends of the blade 31 is positioned higher
than the upper surface 321 of the hub so that there is an
air-intake space is formed between the blades 31 and the upper
surface 321 of the hub 32 for allowing the intake airflow to
axially flow in and radially flow out through the blades as the
dotted line arrows shown in FIG. 4.
Third Embodiment
[0042] FIG. 5 shows an impeller 30b of the third embodiment. The
impeller 30b is similar to the second embodiment except that the
blades 31 of the impeller 30b are arranged as an annular structure
with an outer diameter D.sub.1 greater than the outer diameter L of
the hub 32, and an inner diameter d less than the outer diameter L
of the hub 32. Thus, the blades 31 are only directly connected to
the upper surface 321 and the corner 324 of the hub 32.
Furthermore, the blades 31 of this embodiment are radially extended
and an outer edge 31d of the blade is protruded out from the corner
324 so that the blades are wider than those of the above-described
embodiments. Namely, compared to the above-described embodiments,
this embodiment can utilize a motor with smaller diameter L.
[0043] Additionally, although the size of the motor or the
connection between the blades 31 and the hub 32 varies, the inlet
area remains constant. Thus, the performance of the fan is greatly
improved.
Fourth Embodiment
[0044] FIG. 6A is a schematic diagram of an impeller 30c of the
fourth embodiment. FIG. 6B is a cross section viewed along line BB'
of FIG. 6A. The impeller 30c is similar to the third embodiment
except that the blades 31 are formed into an annular structure with
an outer diameter D.sub.1 equal to the outer diameter L of the hub
32. Thus, as shown in FIGS. 6A and 6B, each blade 31 is only
directly connected to the upper surface 322 and the corner 324 of
the hub 32 and the outer edge 31d is aligned with the axial
sidewall 322. The inlet area remains unchanged. Thus, the present
invention can be utilized in a fan with a motor of any diameter
L.
Fifth Embodiment
[0045] FIG. 7 is a cross section of an impeller 30d of the fifth
embodiment. The impeller 30d is similar to the fourth embodiment
except that the blades 31 are arranged as an annular structure with
an outer diameter D.sub.1 smaller than the outer diameter L of the
hub 32. Each blade 31 is disposed on and only connected to the
upper surface 321 of the hub 32. The inlet area remains the same as
the above embodiments, and thus, the present invention can be
utilized in a fan with a motor of any diameter L.
[0046] In conclusion, the present invention has blades directly
connected to the upper surface, the corner or the axial sidewall of
the hub. No gap is formed between the blades and the hub. Instead,
an open space is surrounded by the blades and above the hub. Thus,
the strength of the impeller is improved without sacrificing the
inlet area size. Additionally, instead of using a thick motor, a
thin and wide motor with the same power and performance is used for
the impeller according to the present invention. Thus, the impeller
of the present invention not only has greater strength but also
provides larger air inflow to increase rotational speed and provide
better performance.
[0047] Finally, while the invention has been described by way of
example and in terms of the preferred embodiments, it is to be
understood that the invention is not limited to the disclosed
embodiments. On the contrary, it is intended to cover various
modifications and similar arrangements as would be apparent to
those skilled in the art. Therefore, the scope of the appended
claims should be accorded the broadest interpretation so as to
encompass all such modifications and similar arrangements.
* * * * *