U.S. patent application number 10/989862 was filed with the patent office on 2005-09-29 for fan frame and mold for making the same.
This patent application is currently assigned to HON HAI Precision Industry CO., LTD.. Invention is credited to Ku, Chin-Long, Yeh, Chin-Wen.
Application Number | 20050214142 10/989862 |
Document ID | / |
Family ID | 34775179 |
Filed Date | 2005-09-29 |
United States Patent
Application |
20050214142 |
Kind Code |
A1 |
Ku, Chin-Long ; et
al. |
September 29, 2005 |
Fan frame and mold for making the same
Abstract
A heat dissipation assembly includes a fan frame (11), a blade
set (12) rotably mounted in the fan frame, a support member (30)
abutting the fan frame, and a number of fasteners (20) mounting the
fan frame on the support member. The fan frame defines an inner
cavity receiving the blade set, a number of circular through
apertures (18) for insertion of the fasteners respectively, and a
number of slits (19) communicating with the through apertures to
allow the through apertures to be resiliently expandable. For
making the fan frame, a female mold (50) includes a number of posts
(56) extending therefrom, and a connecting plate (58) connected
between a main part of the female mold and each post.
Inventors: |
Ku, Chin-Long; (Tu-Cheng,
TW) ; Yeh, Chin-Wen; (Tu-Cheng, TW) |
Correspondence
Address: |
MORRIS MANNING & MARTIN LLP
1600 ATLANTA FINANCIAL CENTER
3343 PEACHTREE ROAD, NE
ATLANTA
GA
30326-1044
US
|
Assignee: |
HON HAI Precision Industry CO.,
LTD.
Tu-Cheng City
TW
|
Family ID: |
34775179 |
Appl. No.: |
10/989862 |
Filed: |
November 15, 2004 |
Current U.S.
Class: |
417/423.8 ;
417/366; 417/423.3 |
Current CPC
Class: |
F04D 29/545
20130101 |
Class at
Publication: |
417/423.8 ;
417/423.3; 417/366 |
International
Class: |
F04B 017/00; F04B
039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2004 |
CN |
200420044248.X |
Claims
What is claimed is:
1. A heat dissipation assembly comprising: a fan frame defining an
inner cavity, a plurality of circular through apertures around the
inner cavity, a plurality of slits communicating with the through
apertures to allow the through apertures to be resiliently
expandable; a blade set rotatably mounted in the inner cavity; a
support member supporting the fan frame thereon; and a plurality of
fasteners extending through the through apertures respectively and
engaging with the support member so as to mount the fan frame on
the support member.
2. The assembly as described in claim 1, wherein the fan frame has
a square outer periphery with the through apertures defined at
corners thereof respectively.
3. The assembly as described in claim 1, wherein the slits are in
communication with an exterior of the fan frame thereby making the
through apertures open outwardly.
4. The assembly as described in claim 1, wherein the fasteners are
screws.
5. The assembly as described in claim 1, wherein the support member
is a fan holder that is secure to a heat sink.
6. The assembly as described in claim 1, wherein the support member
is a heat sink.
7. The assembly as described in claim 1, wherein the support member
is a wall of a computer case.
8. A mold for making a fan frame, the mold comprising: a male mold;
and a female mold comprising a main part having a bottom wall and a
plurality of sidewalls extending from the bottom wall to
cooperatively define an inner space therebetween for receiving the
male mold therein, the male mold and the female mold cooperatively
defining a gap resembling the shape of the fan frame therebetween,
a plurality of posts having a same height extending perpendicularly
from the bottom wall, a connecting plate connected between the main
part and each of the posts.
9. The mold as described in claim 8, wherein the connecting plate
has a same height with the post.
10. The mold as described in claim 9, wherein the connecting plate
is connected to a junction of two adjacent sidewalls.
11. The mold as described in claim 8, wherein the connecting plate
is perpendicular to the bottom wall.
12. A fan for heat dissipation, comprising: a blade set; and a fan
frame receiving said blade set so as to keep said blade set
operatable therein, said fan frame having a plurality of through
apertures disposed around said blade set, each of said through
apertures extending through said fan frame to expose to outside of
said fan frame at two opposing ends thereof, and at least one slit
formed with said each of said through apertures to allow said each
of said through apertures communicating with outside of said fan
frame from a face of said each of said through apertures other than
said two opposing ends.
13. The fan as described in claim 12, wherein said each of said
through apertures is resiliently extendable along a direction
perpendicular to an extending direction of said at least one slit.
Description
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to cooling fans for
use in heat dissipation assemblies for cooling electronic packages,
and more particularly to a fan frame of a cooling fan and a mold
for making the fan frame.
[0003] FIG. 3 illustrates a conventional cooling fan 100 having a
frame 101 with an inner cavity, and a blade set 103 rotatably
received in the inner cavity. Four through holes 105 are formed at
corners of the frame 101 respectively. The through holes 105 allow
fasteners such as screws to extend therethrough and engage in
another member, such as a fan holder which is secured on a heat
sink, thereby mounting the cooling fan 100 on the heat sink. The
periphery of the frame 101 adjacent each hole 105 is thinner than
adjacent portion of the frame 101, and therefore forms a localized
area of high stress also referred to as stress concentration at the
thinner portion of the frame 101. When the screw 105 engages in the
hole 105, these thinner portions of the frame 101 at the holes 105
are prone to be damaged.
[0004] FIG. 4 illustrates a mold for making the frame 101 of the
conventional fan 100. The mold comprises a female mold 90 and a
male mold 80 inserting into the female mold 90. A gap 70 is formed
between the female mold 90 and the male mold 80. The gap 70 has a
shape of the frame 101. In molding, molten plastic is injected into
the gap 70, and the mold is cooled to freeze the plastic to form
the shape of the frame 101.
[0005] Referring to FIGS. 5 and 6, in order to form the though
holes 105 of the frame 101, four posts 92 are formed on a bottom
wall of the female mold 90. Each post 92 is slim, and is connected
to the bottom wall of the female mold 90 with only one end of the
post 92 joining with the bottom wall of the female mold 90. This
configuration will cause stress concentration at a joint area 94.
When the post 92 is subject to vibration or shock during
transportation of the mold or subject to unexpected radial force
during the molding process, the post 92 is very likely to break off
from the joint area 94.
[0006] For the foregoing reasons, there is a need for a fan frame
which has an improved resistance against breakage, and also there
is a need for a mold molding the fan frame which has an improved
resistance against unexpected shock or force.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to cooling fan whose fan
frame has an improved resistance to breakage due to stress
concentration.
[0008] The present invention is also directed to a mold for making
the fan frame which has improved resistance against unexpected
shock or force.
[0009] A cooling fan in according with a preferred embodiment of
the present invention comprises a fan frame, a blade set rotably
mounted in the fan frame, a support member abutting the fan frame,
and a plurality of fasteners mounting the fan frame on the support
member. The fan frame defines an inner cavity receiving the blade
set, a plurality of circular through apertures for insertion of the
fasteners respectively, and a plurality of slits communicating with
the through apertures to allow the through apertures to be
resiliently expandable.
[0010] A mold for make a fan frame according to a preferred
embodiment of the present invention comprises a male mold and a
female mold cooperatively define a gap resembling the shape of the
fan frame therebetween. The female mold comprises a main part
having a bottom wall and a plurality of sidewalls extending from
the bottom wall. A plurality of posts having a same height extends
perpendicularly from the bottom wall. A connecting plate is
connected between the main part and each of the posts.
[0011] Other objects, advantages and novel features of the present
invention will be drawn from the following detailed description of
the preferred embodiments of the present invention with attached
drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an exploded view of a preferred embodiment of a
heat dissipation assembly having a cooling fan embodying features
of the present invention;
[0013] FIG. 2 is a top, cut view of a mold for the fan frame of
FIG. 1;
[0014] FIG. 3 is a perspective view of a conventional cooling
fan;
[0015] FIG. 4 is an assembled, cross-sectional view of a mold for
the conventional cooling fan of FIG. 5;
[0016] FIG. 5 is a top, cross sectional view of the female mold
along line A-A of FIG. 4; and
[0017] FIG. 6 is a cross-sectional view of the female mold along
line B-B of FIG. 5.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0018] Referring to FIG. 1, a heat dissipation assembly according
to a preferred embodiment of the present invention comprises a
support member 30, a cooling fan 10, and a plurality of fasteners
such as screws 20 for mounting the cooling fan 10 to the support
member 30.
[0019] The cooling fan 10 comprises a fan frame 11 defining an
inner cavity, and a blade set 12 rotatably received in the inner
cavity of the fan frame 11. A plurality of circular apertures 18 is
defined in the fan frame 11 around the cavity, for insertion of the
screws 20 thereinto respectively. In this exemplificative
embodiment, the fan frame 11 has a square outer periphery and the
through apertures 18 are arranged at corners of the fan frame 11
respectively. Understandably, the outer periphery of the fan frame
11 can be round or other shapes according to practice. The fan
frame 11 at each corner thereof splits so as to make each aperture
18 open outwardly, thereby defining a slit 19 at each of the
corners to communicate with both a corresponding aperture 18 and an
exterior of the fan frame 11. These slits 19 allow the through
apertures 18 to be resiliently expandable.
[0020] The support member 30 is an element for mounting the fan
frame 11 and varying with situations in which the cooling fan 10 is
used. Suppose the cooling fan 10 cooperates with a heat sink to
cool an electronic package, the support member 30 is the heat sink
if the cooling fan 10 is directly secured to the heat sink.
However, if a fan holder is used to retain the cooling fan 10 on
the heat sink, the support member 30 is the fan holder. Suppose
another situation, the cooling fan 10 is mounted to a wall of a
computer enclosure at a venting hole thereof for ventilation of the
computer enclosure, the support member is the wall of the computer
enclosure.
[0021] Referring to FIG. 2, a mold for making the fan frame 11 is
shown. FIG. 2 only shows a female mold 50. The female mold 50
comprises a bottom wall 52 and four sidewalls 54 extending
perpendicularly from sides of the bottom wall 52 to cooperatively
define an inner space therebetween. Four cylindrical posts 56
having a same height extend perpendicularly and upwardly from the
bottom wall 52, near the respective corners of the female mold 50.
A connecting plate 58 extends in a radial direction from a
periphery of each post 56 to a junction of two adjacent sidewalls
54. A junction line of each post 56 and a corresponding connecting
plate 58 is parallel to the axis of the post 56. Each connecting
plate 58 has a same height with the post 56.
[0022] The conventional male mold, such as the male mold 80 shown
in FIG. 4, may be adopted to cooperate with the female mold 80 of
the present invention to mold the fan frame 11. The male mold 80 is
received in the inner space of the female mold 50. A gap resembling
the shape of the fan frame is formed between the male mold 80 and
the female mold 50. In molding the fan frame 11, molten plastic
material is injected into the gap. After the molten plastic
solidify to form the fan frame 11, the male mold 80 is withdrawn
from the female mold 50. Then the fan frame 11 is removed from the
female mold 50.
[0023] In the fan frame 11 according to the present invention, the
slits 19 allow the fan frame 11 adjacent corresponding apertures 18
to resiliently deform to expand the apertures 18, therefore
eliminate the stress concentration phenomena of the fan frame at
the apertures 18. In the mold according to the present invention,
each post 56 connects to the main part of the female mold 50 not
only by its bottom end fixed to the bottom wall 52 of the female
mold 50, but also by its periphery fixed to the connecting plate 58
which is connected to the sidewalls 54. This arrangement greatly
increases the joining force between the post 56 and the main part
of the female mold 50. The post 56 is thus able to withstand
greater shock during transportation and radial force during molding
process or machining of the post 56 itself.
[0024] It is understood that the invention may be embodied in other
forms without departing from the spirit thereof. The
above-described examples and embodiments are to be considered in
all respects as illustrative and not restrictive, and the invention
is not to be limited to the details given above.
* * * * *