U.S. patent application number 13/036649 was filed with the patent office on 2012-08-30 for round axial fan with balancing structure.
Invention is credited to Wen-Hao Liu.
Application Number | 20120219419 13/036649 |
Document ID | / |
Family ID | 46719095 |
Filed Date | 2012-08-30 |
United States Patent
Application |
20120219419 |
Kind Code |
A1 |
Liu; Wen-Hao |
August 30, 2012 |
ROUND AXIAL FAN WITH BALANCING STRUCTURE
Abstract
A round axial fan with balancing structure includes a hub, a
ring-shaped band located around an outer side of the hub, and a
plurality of blades extended between the hub and the ring-shaped
band. At least one removable area is defined on the ring-shaped
band for serving as a balancing area. By determining and removing
one or more balancing areas at appropriate locations from the
ring-shaped band, uneven weight distribution of the components of
the round axial fan can be adjusted to enable stable rotation of
the fan without producing vibration. The provision of the balancing
area on the ring-shaped band of the round axial fan also enables
reduced material and labor costs for adjusting the weight
distribution of the fan.
Inventors: |
Liu; Wen-Hao; (New Taipei
City, TW) |
Family ID: |
46719095 |
Appl. No.: |
13/036649 |
Filed: |
February 28, 2011 |
Current U.S.
Class: |
416/144 |
Current CPC
Class: |
F04D 25/0613 20130101;
F04D 29/326 20130101; F04D 29/662 20130101 |
Class at
Publication: |
416/144 |
International
Class: |
F01D 25/04 20060101
F01D025/04 |
Claims
1. A round axial fan with balancing structure, comprising a hub; a
ring-shaped band located around an outer side of the hub to thereby
define an annular flow passage between the hub and the ring-shaped
band; a plurality of blades located in the annular flow passage,
the blades respectively having a radially inner end connected to an
outer circumferential surface of the hub and a radially outer end
connected to an inner circumferential surface of the ring-shaped
band; and at least one removable area defined on the ring-shaped
band for serving as a balancing area; whereby, by determining and
removing one or more balancing areas at appropriate locations from
the ring-shaped band, an overall weight distribution of the round
axial fan can be adjusted to enable stable rotation of the fan.
2. The round axial fan with balancing structure as claimed in claim
1, wherein the ring-shaped band has a first end face and a second
end face separately located at two opposite sides of the
ring-shaped band.
3. The round axial fan with balancing structure as claimed in claim
2, wherein the first end face and the second end face include a
first and a second radially outward extended end flange,
respectively.
4. The round axial fan with balancing structure as claimed in claim
2, wherein the at least one balancing area is provided on the first
end face.
5. The round axial fan with balancing structure as claimed in claim
2, wherein the at least one balancing area is provided on the
second end face.
6. The round axial fan with balancing structure as claimed in claim
2, wherein the at least one balancing area is provided on both of
the first and the second end face.
7. The round axial fan with balancing structure as claimed in claim
3, wherein the at least one balancing area is provided on the first
end flange at the first end face, and a notch is formed on the
first end flange when the balancing area is removed therefrom.
8. The round axial fan with balancing structure as claimed in claim
3, wherein the at least one balancing area is provided on the
second end flange at the second end face, and a notch is formed on
the second end flange when the balancing area is removed
therefrom.
9. The round axial fan with balancing structure as claimed in claim
3, wherein the at least one balancing area is provided on both of
the first and the second end flange at the first and the second end
face, respectively; and a notch is formed on each of the first and
the second end flange when the balancing area is removed
therefrom.
10. The round axial fan with balancing structure as claimed in
claim 2, wherein a radius of the first end face relative to a
center of the hub is equal to a radius of the second end face
relative to the center of the hub.
11. The round axial fan with balancing structure as claimed in
claim 2, wherein a radius of the first end face relative to a
center of the hub is larger than a radius of the second end face
relative to the center of the hub.
12. The round axial fan with balancing structure as claimed in
claim 2, wherein a radius of the second end face relative to a
center of the hub is larger than a radius of the first end face
relative to the center of the hub.
13. The round axial fan with balancing structure as claimed in
claim 1, further comprising a shielding member attached to an outer
surface of the at least one balancing area.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a balancing structure, and
more particularly to a round axial fan using such balancing
structure to enable quick adjustment of the weight distribution of
the round axial fan, so that the round axial fan can rotate stably
and the material and labor costs for balancing the fan can be
reduced.
BACKGROUND OF THE INVENTION
[0002] Electronic information products, including computers, have
now become very popular among consumers and provide very wide
applications. Consumers' wide demands also lead to rapid technical
development in the electronic information industry. While the
current electronic information products have increasingly upgraded
computing speed and access capacity, the heat produced by the
components in the electronic information products during high-speed
operation thereof also increases. To remove the heat produced by
the components from the electronic information products, heat sinks
and cooling fans are usually provided in the electronic information
products at positions of heat source.
[0003] Cooling fans can be generally divided into two types,
namely, axial fans and centrifugal fans. A round axial fan is one
type of the axial fans. The round axial fan includes a hub, a
plurality of blades radially outward extended from the hub, and a
ring-shaped band integrally connected to the radially outer ends of
the blades. The round axial fan is formed by injection molding. In
the process of injection molding, there are times the
injection-molding material is not uniformly injected to thereby
result in uneven weight distribution of the hub, the blades or the
ring-shaped band. The uneven weight distribution of the hub, the
blades or the ring-shaped band has adverse influence on the
balanced rotation of the round axial fan. That is, when the weight
distribution of the hub, the blades or the ring-shaped band is
uneven, the whole round axial fan would tilt during rotation to
result in abrasion and vibration of the central shaft of the round
axial fan relative to the bearing cup of the base supporting the
round axial fan. The abrasion and vibration of the central shaft
not only produces noise, but also accelerates the fatigue of the
central shaft of the round axial fan to shorten the service life
thereof. The fan device using the round axial fan would have
reduced overall quality and provide poor heat dissipation
effect.
[0004] To solve the problem of uneven weight distribution of the
round axial fan, there are manufacturers who try to adjust the
uneven weight distribution by locally providing weights on the hub
of the round axial fan. FIG. 1 is a perspective view showing a
conventional round axial fan with balancing structure. The
conventional round axial fan 10 includes a hub 11 and a ring-shaped
band 12. At least one blade 13 is provided between the hub 11 and
the ring-shaped band 12. The radius of the hub 11 relative to a
center of the round axial fan 10 is smaller than the radius of the
ring-shaped band 12 relative to the center of the round axial fan
10. At least one recess 111 is formed on the hub 11. In the case
the round axial fan 10 tilts during rotation due to uneven weight
distribution of the fan 10, weights are directly fitted in correct
recesses 111 to balance the weight distribution of the fan 10.
However, since there is a difference between the radii of the hub
11 and the ring-shaped band 12, the weights fitted in the recesses
111 on the hub 11 must be several times as heavy as the ring-shaped
band 12 to reach the required balance. Therefore, the cost for
providing the weights on the hub 11 is high. Further, with the
weights fitted on the hub 11, the round axial fan 10 in rotating is
still subject to tilting due to the uneven weight distribution of
the ring-shaped band 12 and the large radius thereof. As a result,
the abrasion and vibration of the central shaft of the round axial
fan 10 relative to the bearing cup on the base of the fan is
increased and requires more time and labor to adjust the overall
weight distribution of the round axial fan 10.
[0005] In brief, the conventional round axial fan with balancing
structure has the following disadvantages: (1) By fitting the
weights on the hub, increased material for the weights is needed to
achieve the purpose of balancing the fan; (2) the balance achieved
by fitting the weights on the hub is easily adversely affected by
the large radius and the uneven weight distribution of the
ring-shaped band; and (3) additional material and labor costs are
required to adjust the weight distribution of the round axial
fan.
[0006] It is therefore tried by the inventor to develop an improved
round axial fan with balancing structure in order to overcome the
disadvantages in the prior art.
SUMMARY OF THE INVENTION
[0007] A primary object of the present invention is to provide a
round axial fan with balancing structure, so that the round axial
fan can be quickly adjusted to achieve balanced weight distribution
and accordingly stable rotation thereof.
[0008] Another object of the present invention is to provide a
round axial fan with balancing structure, so that material and
labor costs for adjusting the weight distribution of the round
axial fan can be reduced.
[0009] A further object of the present invention is to provide a
round axial fan with balancing structure, in which a shielding
member is attached to at least one balancing area provided on the
fan, so that the function of the round axial fan to produce airflow
is not adversely affected by the balancing area when the same is
removed from the fan to balance the weight distribution of the
fan.
[0010] To achieve the above and other objects, the round axial fan
with balancing structure according to the present invention
includes a hub; a ring-shaped band located around an outer side of
the hub to thereby define an annular flow passage between the hub
and the ring-shaped band; a plurality of blades located in the
annular flow passage, the blades respectively having a radially
inner end connected to an outer circumferential surface of the hub
and a radially outer end connected to an inner circumferential
surface of the ring-shaped band; and at least one removable area
defined on the ring-shaped band for serving as a balancing area. By
determining and removing one or more balancing areas at appropriate
locations from the ring-shaped band, it is able to adjust an
overall weight distribution of the round axial fan for the same to
rotate stably.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The structure and the technical means adopted by the present
invention to achieve the above and other objects can be best
understood by referring to the following detailed description of
the preferred embodiments and the accompanying drawings,
wherein
[0012] FIG. 1 is a perspective view showing a conventional round
axial fan with balancing structure;
[0013] FIG. 2 is a top perspective view showing a round axial fan
with balancing structure according to a first preferred embodiment
of the present invention;
[0014] FIG. 3 is a bottom perspective view of the round axial fan
with balancing structure according to the first preferred
embodiment of the present invention;
[0015] FIG. 4 is a sectioned side view of the round axial fan with
balancing structure according to the first preferred embodiment of
the present invention;
[0016] FIG. 5A is a sectioned side view of a round axial fan with
balancing structure according to a second preferred embodiment of
the present invention;
[0017] FIG. 5B is a sectioned side view of a round axial fan with
balancing structure according to a third preferred embodiment of
the present invention;
[0018] FIG. 6A is a top perspective view showing a round axial fan
with balancing structure according to a fourth preferred embodiment
of the present invention;
[0019] FIG. 6B is a bottom perspective view of the round axial fan
with balancing structure according to the fourth preferred
embodiment of the present invention; and
[0020] FIG. 6C is a sectioned side view of the round axial fan with
balancing structure according to the fourth preferred embodiment of
the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The present invention will now be described with some
preferred embodiments thereof and with reference to the
accompanying drawing. For the purpose of easy to understand,
elements that are the same in the preferred embodiments are denoted
by the same reference numerals.
[0022] Please refer to FIGS. 2, 3 and 4 that are front perspective,
rear perspective and sectioned side views, respectively, of a round
axial fan with balancing structure according to a first preferred
embodiment of the present invention. As shown, the round axial fan
20 includes a hub 30 and a ring-shaped band 40 located around an
outer side of the hub 30 to thereby define an annular flow passage
31 between the hub 30 and the ring-shaped band 40. The ring-shaped
band 40 has a first end face 41 and a second end face 42
respectively located at an upper and a lower side of the
ring-shaped band 40. A radius of the first end face 41 relative to
a center of the hub 30 may be larger than, equal to, or smaller
than a radius of the second end face 42 relative to the center of
the hub 30. In the illustrated first preferred embodiment, the
radius of the first end face 41 relative to the center of the hub
30 is equal to the radius of the second end face 42 relative to the
center of the hub 30.
[0023] In the annular flow passage 31, there is provided a
plurality of blades 50. The blades 50 each have a radially inner
end 51 connected to an outer circumferential surface of the hub 30
and a radially outer end 52 connected to an inner circumferential
surface of the ring-shaped band 40. The blades 50 in rotating are
able to guide airflow to move, so as to produce air convection to
carry away heat produced by a heat-producing element. On the
ring-shaped band 40, there is defined at least one removable area
that can be removed from the ring-shaped band 40 to serve as a
balancing area 60. A shielding member 61 is attached to an outer
surface of the at least one balancing area 60 provided on the
ring-shaped band 40, so as to effectively stop airflow from
entering into a void at the balancing area 60 when it is removed
from the ring-shaped band 40.
[0024] The at least one balancing area 60 is defined on the
ring-shaped band 40 for adjusting uneven eight distribution of the
round axial fan 20 when the same shows an unbalanced state and/or
vibrates while rotating due to uneven weight distribution of the
hub 30, the ring-shaped band 40 or the blades 50, or between the
first end face 41 and the second end face 42 of the ring-shaped
band 40. The at least one balancing area 60 may be defined on the
first end face 41 of the ring-shaped band 40, as shown in FIG. 2;
or be defined on the second end face 42 of the ring-shaped band 40,
as shown in FIG. 3; or be defined on both of the first and the
second end 41, 42 of the ring-shaped band 40, as shown in FIG. 4.
In the illustrated first preferred embodiment, when uneven weight
distribution of the hub 30, the ring-shaped band 40 or the blades
50, or between the first end face 41 and the second end face 42 of
the ring-shaped band 40 is found, one or more of the at least one
balancing area 60 at appropriate positions are removed from the
ring-shaped band 40 to form one or more holes thereon, so as to
adjust the weight distribution of the hub 30, the ring-shaped band
40 or the blades 50, allowing the round axial fan 20 to be quickly
adjusted for rotating in a balanced state. By performing the weight
distribution adjustment on the ring-shaped band 40 instead of the
hub 30, the number of required balancing areas 60 can be
effectively reduced to achieve the purpose of saving the labor and
material costs for adjusting the weight distribution of different
components of the round axial fan 20. Further, the condition of a
tilted round axial fan 20 during rotation thereof caused by
non-uniform radius and weight distribution of the hub 30 and the
ring-shaped band 40 can be avoided to enable further saving of the
material and labor costs.
[0025] FIG. 5A is a sectioned side view of a round axial fan with
balancing structure according to a second preferred embodiment of
the present invention. In the second preferred embodiment, a radius
of the first end face 41 relative to a center of the hub 30 can be
larger than a radius of the second end face 42 relative to the
center of the hub 30 according to actual need, and the at least one
balancing area 60 is defined on the first end face 41.
Alternatively, according to a third preferred embodiment of the
present invention as shown in FIG. 5B, the radius of the second end
face 42 relative to the center of the hub 30 can be larger than the
radius of the first end face 41 relative to the center of the hub
30 according to actual need, and the at least one balancing area 60
is defined on the second end face 42. By determining and removing
one or more balancing areas 60 at appropriate locations from the
ring-shaped band 40, the uneven weight distribution of the hub 30,
the ring-shaped band 40 or the blades 50, or between the first end
face 41 and the second end face 42 of the ring-shaped band 40 can
be adjusted for the whole round axial fan 20 to rotate in a
balanced manner.
[0026] FIGS. 6A, 6B and 6C illustrate a fourth preferred embodiment
of the present invention. Since the components and the connection
relation therebetween in the fourth embodiment are generally
similar to those in the previous embodiments, they are not
repeatedly described herein. However, the fourth embodiment is
different from the previous embodiments in that the first end face
41 and the second end face 42 include a first radially outward
extended end flange 411 and a second radially outward extended end
flange 421, respectively; and the at least one balancing area 60 is
defined on the first end flange 411 at the first end face 41 of the
ring-shaped band 40 as shown in FIG. 6A, or on the second end
flange 421 at the second end face 42 of the ring-shaped band 40 as
shown in FIG. 6B, or on both of the first and the second end flange
411, 421 at the first and the second end face 41, 42 of the
ring-shaped band 40, respectively, as shown in FIG. 6C. When the
balancing area 60 is removed from the first and/or the second end
flange 411, 421 for the purpose of adjusting the weight
distribution of the hub 30, the ring-shaped band 40 or the blades
50, or between the first end face 41 and the second end face 42 of
the ring-shaped band 40, a notch is formed on the first and/or the
second end flange 411, 421 to achieve the same function of
adjusting the overall weight distribution of the round axial fan 20
for the same to rotate in a balanced manner.
[0027] In conclusion, the round axial fan with balancing structure
according to the present invention has the following advantages:
(1) by defining the balancing area or areas on the ring-shaped
band, the labor and material costs required to adjust the weight
distribution of different components of the round axial fan can be
reduced; (2) by defining the balancing area or areas on the
ring-shaped band to adjust the weight distribution of different
components of the round axial fan, it is able to avoid adverse
influence on the balance of the round axial fan by the large radius
and uneven weight of the ring-shaped band; (3) the material needed
for balancing the round axial fan can be saved; (4) the labor cost
for balancing the round axial fan can be reduced; and (5) the
service life of the round axial fan can be prolonged.
[0028] The present invention has been described with some preferred
embodiments thereof and it is understood that many changes and
modifications in the described embodiments can be carried out
without departing from the scope and the spirit of the invention
that is intended to be limited only by the appended claims.
* * * * *