U.S. patent application number 10/711852 was filed with the patent office on 2006-04-13 for bi-directional blowers for cooling laptop computers.
This patent application is currently assigned to NONLINEAR TECH, INC.. Invention is credited to Wen-Chun Zheng.
Application Number | 20060078423 10/711852 |
Document ID | / |
Family ID | 35305640 |
Filed Date | 2006-04-13 |
United States Patent
Application |
20060078423 |
Kind Code |
A1 |
Zheng; Wen-Chun |
April 13, 2006 |
Bi-directional Blowers for Cooling Laptop Computers
Abstract
Bi-directional Blowers capable of sucking-in ambient air and
blowing-out hot air from system box simultaneously are invented to
cool computer or electronic systems. The application to cooling
laptop computers is disclosed in very details. The bi-directional
blowers are comprised of a DC or AC motor, a rotary part of blades
and/or impellers, an optional cover, and a housing frame with
built-in broken walls, stationary blades and airfoils, which
control the flow volume and direction. The separate zone to divide
the blow-out and suck-in channels is constructed using the broken
walls with conjunction of the blades and/or impellers. The rotary
part is the radial blades, or a combination of blades and
impellers. Two types of bi-directional blowers are explored: the
pressure type and hybrid type. A one-way blower of pressure type
utilizes the same principle of the bi-directional blowers such that
the inlet and outlet can be located on sides of the blower. With
the advantages of the invention, the air gap between laptop bottom
and top surface of the desk can be eliminated for better heat
conduction through lower side because the desk can be used as a
natural heat sink.
Inventors: |
Zheng; Wen-Chun; (San Jose,
CA) |
Correspondence
Address: |
PATENT LAW GROUP LLP
2635 NORTH FIRST STREET
SUITE 223
SAN JOSE
CA
95134
US
|
Assignee: |
NONLINEAR TECH, INC.
551 Crystalberry Ter.
San Jose
CA
|
Family ID: |
35305640 |
Appl. No.: |
10/711852 |
Filed: |
October 8, 2004 |
Current U.S.
Class: |
415/206 |
Current CPC
Class: |
F04D 17/04 20130101;
F04D 25/0613 20130101; F04D 29/424 20130101; F04D 29/4246 20130101;
F04D 29/444 20130101 |
Class at
Publication: |
415/206 |
International
Class: |
F04D 29/44 20060101
F04D029/44 |
Claims
1. A Bi-directional Blower with the functions of suck-in ambient
air and blow-out hot air from system box simultaneously for
computer and electronic systems comprising: A housing frame of
molded plastics or casted metal with built-in broken walls which
forms a separate zone with conjunction of blades and/or impellers
to construct suck-in and blow-out channels, stationary blades and
airfoils which are designed to control flow volume as well as flow
directions; vents of intakes and outlets may be located on sides,
top or bottom; A molded plastics rotary part of radial blades or a
combination of blades and impellers sitting on a circular plate
which is extended from the drum of the rotary part; A DC or AC
motor, which rotor is mounted with the rotary blades or impellers,
and the stator is assembled to the housing frame; A cover of molded
plastics or sheet metal aligned to the housing frame, which is
optional depending on the application situation.
2. A pressure type bi-directional blower for cooling laptop
computer of claim 1, wherein the so called "negative pressure"
formed behind separate zone draws air into the space between
blades/impellers which drive air out through the outlets.
3. A hybrid type bi-directional blower for laptop computer cooling
of claim 1, wherein the inlet for suck-in ambient air may be
located on top or bottom and hence this suck-in channel is
centrifugal type but the blow-out hot air channel is pressure
type.
4. A combination of blades and impellers sitting on a circular
plate extended from the drum of the rotary part in claim 1, wherein
the blades provide air supply to the forward impellers which moves
air out faster.
5. A pressure type one way blower of claim 1, wherein there are one
inlet and one outlet of the housing frame with the features of
broken walls, stationary blades and airfoils which control the air
flow volume as well as direction. The blowers of this type with
inlet and outlet on sides can eliminate the air gap between the
bottom of a laptop and the top of the desk, so that the heat
conduction through bottom side can be enhanced dramatically.
6. A centrifugal blower with broken walls, stationary blades and
airfoils of claim 1, which control air flow volume as well as
directions for even air flow across the outlet area before heat
sink.
7. The generalized air exchangers, fluid pumps, wherein
bi-directional flow is enabled utilizing the mechanism of claim 1,
i.e., the separate zone constructed with the broken walls, blades
and/or impellers, the stationary blades and tunnels to control the
flow volume as well as directions.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to the field of thermal
management for computer and electronics systems and more
specifically to bi-directional blowers for cooling laptop
computers.
[0002] Fans and blowers are the essential components in the active
air cooling for computer and electronics systems, as the power is
increasing dramatically. To extend air cooling limit and make more
efficient air cooling, duct cooling must be utilized. Because the
heat density in a system is different in various zones, the ideal
approach is to remove heat from hot region to outside of system box
immediately through duct. However, it is a real challenge to make
it happen because of the compact design with many different
components such as CPU, PCI components, graphics and network
processors, memory and other components.
[0003] Axial fans are normally used in desktop, server systems
because axial fans are the most efficient way to move air in same
direction, but blowers are commonly used for laptop cooling because
of the space limitation. Axial fan is more efficient because its
blades cut air mass from intake side and move it to other side
immediately. A same size centrifugal blower is not as efficient as
an axial fan because of these reasons: 1) the intake size is much
smaller; 2) the air mass moves out of the blades driven by
centrifugal force due to the high rotational speed of the blades or
impellers; 3) most of the air mass will have to go through the
circular tunnel before it escapes through outlet; 4) and further,
the air is dragged by the tunnel walls during circular movement.
However, blowers are still widely used because it has unique
advantages of changing air flow direction, fitting in constraint
space, and cooling small hot device such as a heat sink.
[0004] Overheating is a common problem for high power laptop,
although blowers have had to be used for laptop cooling due to
space limitation. The inlet of the centrifugal blower in the laptop
cooling model is usually located at the bottom near CPU. This
requires a 2.about.4 mm air gap between the laptop bottom and the
desk top surface, so that the "warm" air can flow into the blower.
Therefore, the air gap forms a huge thermal resistance in the heat
transfer path of lower side. Assuming the desk is made of wood, its
thermal conductivity is about 7.about.12 times of natural air.
Clearly, the thinner the air gap, the more efficient the heat
dissipation through bottom side because the desk underneath can be
utilized as a huge natural heat sink.
BRIEF SUMMARY OF THE INVENTION
[0005] The primary object of the invention is that the
bi-directional blowers that blow hot air out from the system box
and suck room air into the system box simultaneously.
[0006] Another object of the invention is that the bi-directional
blowers can be used for space constrained conditions, such as
laptop computers, thin blade servers, or PCI cards, e.g., graphics
device, for efficient duct cooling because it plays a role of two
blowers.
[0007] The special object of the invention is that a pressure-type
bi-directional blower can enhance heat dissipation for a laptop
because the cool (room temperature) air is sucked into the box as
well as the hot air is blown out because intakes or outlets are
designed on the sides. Thus the air gap between laptop bottom and
desk top can be eliminated so that the table can be served as a
natural heat sink.
[0008] A further object of the invention is that a hybrid
bi-directional blower maintains the advantages of sucking in cool
air as well as blowing out hot air, but it has higher flow
capability because the blow-in function utilizes centrifugal
mechanism to move air through the intakes located on top or bottom
of the laptop.
[0009] A very valuable object of the invention is that various
rotary blades are explored, for example, a combination of blades
and impeller which makes the bi-directional functions more
efficiently.
[0010] Other objects and advantages of the present invention will
become apparent from the following descriptions, taken in
connection with the accompanying drawings, wherein, by way of
illustration and example, an embodiment of the present invention is
disclosed.
[0011] In accordance with a preferred embodiment of the invention,
the Bi-directional Blowers for cooling laptop computers comprising
a motor, a rotary part of blades and/or impellers, an optional
cover and a housing frame with built-in broken walls, stationary
blades and airfoils. The number of blades should be more than
usual, say more than 18, enough to enable bi-directional functions
effectively. The broken walls with the width same as or wider than
the pitch of rotary blade pitch. While the blades/impellers rotate,
the broken walls with the junction to the blades/impellers will
always form a separate zone, so that suck-in and blow-out functions
can work simultaneously. The stationary blades in the intake or
outlet tunnels are designed to control the flow volume as well as
flow directions. More detailed descriptions will be given as
follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The drawings constitute a part of this specification and
include exemplary embodiments to the invention, which may be
embodied in various forms. It is to be understood that in some
instances various aspects of the invention may be shown exaggerated
or enlarged to facilitate an understanding of the invention.
[0013] FIG. 1 is a perspective view of a pressure type
bi-directional blower, which intakes and outlets are all located on
the sides.
[0014] FIG. 2 is a perspective view of a hybrid type bi-directional
blower, which shows that the function of blowing-out hot air is
pressure type and the function of sucking-in cold air is
centrifugal type with the intakes located on top or bottom
sides.
[0015] FIG. 3 is a perspective view of a pressure type
bi-directional blower, which uses a combination of blades and
impeller as a rotary part.
[0016] FIG. 4 is a perspective view of a hybrid type bi-directional
blower, which uses a combination of blades and impeller as a rotary
part.
[0017] FIG. 5 is a perspective view of a pressure type one way
blower, which shows both inlet and outlet can be located on sides
with various angles.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Detailed descriptions of the preferred embodiment are
provided herein. However, it is to be understood, that the present
invention may be embodied in other forms. Therefore, specific
details disclosed herein are not to be interpreted as limiting, but
rather as a basis for the claims and as a representative basis for
a skilled one to understand the principle of the invention.
[0019] To accomplish the important function of the invention, there
is shown in FIG. 1 the pressure type bi-directional blower used for
a laptop computer. It is assembled with a motor 120 fitted in the
drum of the rotary blade 130, the stator of the motor 120 is
mounted on the housing frame 110, and the optional cover 140. The
structure of the housing is the vital part of the invention. The
broken walls 112 and 113 form a separate zone with the conjunction
of the blades 130 to separate the suck-in and blow-out regions,
such that the intake 102 draws hot air into the blower and blows
out through outlet 101, and the intake 103 draws in cold air and
blows to front of heat sink through outlet 104 to enable duct
cooling, as the motor rotates count clockwise. The separate zone is
actually a gate that blocks air flow from one side to the other.
The stationary blades and airfoils 114 and 115 are designed to
control flow volume and flow directions. The blade should be acute
angles with the air flow velocity vector in order to minimize the
noise due to air dynamics. When rotary blades spin, the stationary
blades distribute flow volumes as even as possible through the
position and intake angles. When air flows into the tunnels among
the airfoils, the velocity of the air mass is adjusted as much as
possible to perpendicular to the outlet area. The motor pin 121
spins in the stator of the motor, which is assembled to the housing
frame 110. The cover 140 is optional depending on how to use the
blower. The screw holes 111 are used to fix the blower to the
system.
[0020] The principle of this invention is that partial vacuum forms
between the blades when they pass the broken walls (the separate
zone) which blocks air flowing from one side to the other. The so
called "negative pressure" sucks air from outside of the blower
into the space between the blades until most of it is driven out
through outlet by the centrifugal force. This periodic rotating
forms suck-in and blow-out channels.
[0021] Turning to FIG. 2, there is shown the hybrid type
bi-directional blower. All features depicted in this drawing are
similar to FIG. 1. It is called hybrid because the inlet 205, as
current technology, is located on top or bottom of the blower.
Thus, the suck-in function works as conventional centrifugal
blower. It transports air very efficiently because it eliminates
air travel in the circular tunnel as conventional blower. Although
suck-in flow is not as much as a conventional blower of the same
size, the total efficiency is better because the other half blows
out hot air from the system box with the pressure type
mechanism.
[0022] Comparing FIG. 3 with FIG. 1, one can notice that the
difference is the rotary part which is a combination of blades and
impellers sitting on the circular plate extended from the drum. The
separate zone is formed with the broken walls 312, 315, 314 and 313
conjunct with the blades and impellers, such that the suck-in and
blow-out channels are constructed. The blow-out channel draws hot
air from the inlet 302 and expels out through outlet 301 and the
suck-in channel draws cold air from intake 303 without airfoils and
blows to heat sink through outlet 304 for duct cooling, as the
rotary part spins count clockwise. The important embodiment of the
invention depicted in this figure is the combination of blades and
impellers. The inner blades extended from drum drives air from
inlet forward so to provide additional air supply to Impellers
which move air faster than blades.
[0023] Comparing FIG. 2, FIG. 4 shows a hybrid bi-directional
blower in which the rotary part of blades and impellers in FIG. 3
is used to replace the radial blades in FIG. 2.
[0024] FIG. 5 illustrates a pressure type one-way blower. The
rotary part 420 of combination of blades 422 and impellers 421 is
shown in the figure but radial blades can also be applied. Air
flows in through inlet 401 and move around in the circular tunnel
413 formed with the cover 410, and finally escapes through the
outlet 402. There are two significant features: 1) Intake 401 is
located on side of the blower, rather than on top or bottom as
conventional centrifugal blower. Using this type blower, the air
gap between a laptop bottom and desk top side can be eliminated for
better heat conduction, as well as maintain high flow capability;
2) The blocking walls 411, the stationary blades and airfoils 404
shown in the illustration are also very important features in order
to have more evenly air flow across the outlet.
[0025] While the invention has been described in connection with a
preferred embodiment, it is not intended to limit the scope of the
invention to the particular form set forth, but on the contrary, it
is intended to cover such alternatives, modifications, and
equivalents as may be included within the spirit and scope of the
invention as defined by the appended claims.
* * * * *