U.S. patent application number 12/131927 was filed with the patent office on 2009-06-18 for combination axial-flow fan.
This patent application is currently assigned to TAIWEI FAN TECHNOLOGY CO., LTD.. Invention is credited to Chien-Chun Yu.
Application Number | 20090155081 12/131927 |
Document ID | / |
Family ID | 40753503 |
Filed Date | 2009-06-18 |
United States Patent
Application |
20090155081 |
Kind Code |
A1 |
Yu; Chien-Chun |
June 18, 2009 |
COMBINATION AXIAL-FLOW FAN
Abstract
A high-performance low-noise combination axial-flow fan includes
a fan hub that has a center connection portion for the connection
of a fan motor shaft and a plurality of mounting grooves
equiangularly spaced around the periphery, and fan blades each
having a wedge block disposed at the inner end for insertion into
one mounting groove to secure the respective fan blade to the fan
hub so that the fan blades are radially fastened to the fan hub and
no gap is seen between each two adjacent fan blades when viewed
from the front side.
Inventors: |
Yu; Chien-Chun; (Shulin
City, TW) |
Correspondence
Address: |
PAI PATENT & TRADEMARK LAW FIRM
1001 FOURTH AVENUE, SUITE 3200
SEATTLE
WA
98154
US
|
Assignee: |
TAIWEI FAN TECHNOLOGY CO.,
LTD.
Sinjhuang City
TW
|
Family ID: |
40753503 |
Appl. No.: |
12/131927 |
Filed: |
June 3, 2008 |
Current U.S.
Class: |
416/219R |
Current CPC
Class: |
F04D 25/0613 20130101;
F04D 29/34 20130101; F04D 29/329 20130101; F04D 29/646
20130101 |
Class at
Publication: |
416/219.R |
International
Class: |
F01D 5/30 20060101
F01D005/30 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 12, 2007 |
TW |
096222594 |
Claims
1. A combination axial-flow fan, comprising: a fan hub, said fan
hub comprising a center connection portion for the connection of a
fan motor shaft and a plurality of mounting grooves equiangularly
spaced around the periphery thereof, each said mounting groove
having an open side disposed at a rear side of said fan hub; and a
plurality of fan blades, each said fan blade comprising a wedge
block disposed at an inner end thereof insertable through the open
side of one said mounting groove to secure the respective fan blade
to said fan hub.
2. The combination axial-flow fan as claimed in claim 1, wherein
each said mounting groove is a dovetail groove.
3. The combination axial-flow fan as claimed in claim 2, wherein
the wedge block of each said fan blade is a dovetail block.
Description
BACKGROUND OF THE INVENTION
[0001] (a) Field of the Invention
[0002] The present invention relates to a fan and more
particularly, to a combination axial-flow fan for use in a computer
or electronic product for forced air convection cooling.
[0003] (b) Description of the Prior Art
[0004] Regular cooler modules are designed for use in electronic
and photoelectric products to expel waste heat. A typical
conventional cooler module is comprised of a passive heat
dissipation device and an active heat dissipation device. A passive
heat dissipation device can be a heat sink extruded from copper or
aluminum and having multiple radiation fins. An active heat
dissipation device can be an axial-flow fan that forces surrounding
air to cause convection, thereby lowering the surrounding
temperature. A typical conventional axial-flow fan comprises a fan
hub 10 and multiple blades 20 integrated into and extending around
the periphery of the fan hub 10 (see FIG. 6). By means of
controlling a motor to rotate the fan hub 10, the blades 20 produce
a wind pressure, achieving force-air cooling Because the parameters
of 3D camber, angle, number and radius of the fan blades determine
the wind pressure, pressure amount and noise levels, it is the
optimum design where there is no gap structure seen in the fan
blades when viewed from the front side, i.e., the front edge of one
fan blade blocks the rear edge of another adjacent fan blade.
[0005] However, this design is not applicable due to technical
problems in molding technology. A partial fan blade overlapping
arrangement will result in a mold stripping problem after injection
molding. Therefore, there is a gap d' between each two adjacent fan
blades 20 (see FIG. 6), allowing removal of the molded fan from the
mold. The presence of this gap d' is one of the major reasons of
the production of wind noise. It also tends to cause an
insufficient wind pressure problem, which presents difficulties in
satisfying heat dissipation requirements of modern electronic
devices.
SUMMARY OF THE INVENTION
[0006] The present invention has been accomplished under the
circumstances in view. It is therefore one object of the present
invention to provide a combination axial-flow fan, which has the
fan hub and the fan blades separately made and then assembled
together so that the front edge of one fan blade is suspended above
the rear edge of another fan blade, no gap is seen between each two
adjacent fan blades when viewed from the front side, and has high
wind pressure, high wind capacity and low noise level
characteristics.
[0007] To achieve this and other objects of the present invention,
the combination axial-flow fan comprises a fan hub and a set of fan
blades. The fan hub and the fan blades are separately made and then
assembled together. The fan hub comprises a center connection
portion for the connection of a fan motor shaft, and a plurality of
mounting grooves equiangularly spaced around the periphery. Each
fan blade comprises a wedge block disposed at the inner end. The
wedge block can be inserted through the rear open side of one
mounting groove to secure the respective fan blade to the periphery
of the fan hub. The mounting grooves can be dovetail grooves. In
this application, the mounting grooves are dovetail grooves, and
the wedge block of each fan blade is a dovetail block fitting the
dovetail configuration of the mounting grooves.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an exploded view of a combination axial-flow fan
according to the present invention.
[0009] FIG. 2 is an assembly view of the combination axial-flow fan
according to the present invention.
[0010] FIG. 3 is a sectional view of a part of the present
invention, showing the dovetail mounting grooves of the fan
hub.
[0011] FIG. 4 is a sectional elevation of the combination
axial-flow fan according to the present invention.
[0012] FIG. 5 is a front view of the combination axial-flow fan
according to the present invention.
[0013] FIG. 6 is a schematic front view of an axial-flow fan
according to the prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] With reference to FIGS. 1 and 2, a combination axial-flow
fan in accordance with the present invention comprises a fan hub 1
and a plurality of fan blades 2. The fan hub 1 and the fan blades 2
are separately molded from plastics by means of injection molding,
and then assembled together for use as an active heat dissipation
device for the cooling of an electronic product.
[0015] Referring to FIGS. 1 and 2 again, the fan hub 1 may be made
in any of a variety of shapes. According to the present preferred
embodiment, the fan hub 1 is shaped like a round cap, having a
center connection portion 11 at the center for the connection of
the shaft of a fan motor (not shown), and a plurality of mounting
grooves 12 equiangularly spaced around the periphery. The mounting
grooves 12 can be dovetail grooves extending axially towards the
rear side 13 of the fan hub 1 so that each mounting groove 12 has
an open end 121 at the rear side 13 of the fan hub 1.
[0016] Referring to FIGS. 1 and 2 again, the fan blades 2 are
identical in shape, each having a front edge 21, a rear edge 22, an
outer edge 23 and an inner edge 24. There are no particular
limitations on the 3D camber and geometric shape of the fan blades
2. The 3D camber and geometric shape of the fan blades 2 can be
modified to achieve optimum performance subject to aerodynamics.
Each fan blade 2 further has a wedge block 25. The wedge block 25
is a dovetail block fitting the circular shape of the periphery of
the fan hub 1 for engagement into one mounting groove 12 of the fan
hub 1. By means of engaging the wedge blocks 25 of the fan blades 2
into the mounting grooves 12 of the fan hub 1, the fan blades 2 are
fastened to the fan hub 1 and radially equiangularly spaced around
the periphery of the fan hub 1.
[0017] After installation, as shown in FIG. 2, the fan blades 2 are
radially disposed around the fan hub 1 and equiangularly spaced
from one another. Thereafter, the center connection portion 11 of
the fan hub 1 is fastened to the shaft of a fan motor (not shown)
and then the assembly of the fan hub 1 and fan blades 2 is mounted
with the fan motor in a rack, constituting an electric fan for use
in a cooler module for cooling a computer or any of a variety other
electronic products.
[0018] Because the fan hub 1 and the fan blades 2 are separately
molded from plastics and then assembled together, fan blades having
different 3D camber and geometric shape features can be selectively
used with one same fan hub to constitute different combination
axial-flow fans for different applications to satisfy different
cooling requirements, thereby lowering the mold cost. More
particularly, as shown in FIGS. 4 and 5, because the fan blades 2
and the fan hub 1 are separately made and then assembled together,
it is practical to constitute a high-performance axial-flow fan
having low noise level, i.e., the front edge 21 of one fan blade 2
is suspending above the rear edge 22 of another adjacent fan blade
2 so that no gap is seen between each two adjacent fan blades 2
when the axial-flow fan is viewed from the front side (see FIG. 5),
however the desired wind tunnel D is still maintained in between
each two adjacent fan blades 2 (see FIG. 4). This fan structure is
not achievable by conventional fan designs. By means of the
application of the present invention, this fan structure is easily
attainable.
[0019] Although a particular embodiment of the invention has been
described in detail for purposes of illustration, various
modifications and enhancements may be made without departing from
the spirit and scope of the invention. Accordingly, the invention
is not to be limited except as by the appended claims.
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