Title of Invention

A COOLING SYSTEM AND A METHOD OF COOLING A HEAT GENERATING OBJECT

Abstract A cooling system (1) for cooling a heat generating object (C), comprises: a frame (3); a heat exchanger unit (2) connected to the frame (3) such that air flow is capable of passing through the frame in proximity to said heat exchanger unit (2); and a fan unit (4) connected to the frame (3) adjacent to the heat exchanger unit (2), position of the fan unit (4) along the frame (3) being selectively adjustable so that when said fan unit (4) is activated, air flow passes through said frame (3) in a first direction through a first portion of the heat exchanger unit (2) and a second direction substantially opposite the first direction through a second portion of the heat exchanger unit (2).
Full Text A COOLING SYSTEM AND A METHOD OF COOLING A HEAT
GENERATING OBJECT
Technical Field of the Invention
The present invention relates to a cooling system and a method of
cooling a heat generating object and is suitable for cooling electronic equipment.
It particularly relates to systems for cooling electronic equipment that are
reconfigurable to allow customized air flow in proximity to the electronic
equipment.
Background and Objects of the Invention
The growth of the computer industry and telephony over the past few
decades has been phenomenal. The integration of these technologies, for
example, in telecommunications switching systems, has lead to greater and
greater efficiencies as larger numbers of communications are handled by fewer
components, which are typically housed in a central control room.
One problem inherent with many existing cooling systems for electronic
equipment is rigidity. Many existing cooling systems are built into and/or under
the flooring of a temperature-controlled room having equipment needing to be
cooled. Such cooling systems employ fixed conduits or other piping for directing
cooled air along a subsurface of the flooring and upwardly through the floor and
towards the equipment to be cooled. The upwardly directed cooled air is in
proximity to the equipment. In the event the temperature characteristics within
the temperature-cooled room changes, such as by the equipment being moved
within the room or by additional equipment being added therein, it is very difficult
to modify the cooling system accordingly. For instance, the conduits
have to be detached from their fixed positions and repositioned, or replaced

in favor of differently sized conduits. Consequently, altering the cooling characteristics of existing
cooling systems frequently proves a costly adventure.
Floor-based cooling systems present additional difficulties other than rigidity in its cooling
characteristics. For instance, floor-based cooling systems that do not utilize conduits for passing
cooled air occupy more area so that equipment cabling and other obstructions do not cause uneven
air distribution or a reduction in air pressure. Such systems require the equipment cabling to be
plenum rated, thereby increasing system cost. Floor-based cooling systems also possess the
tendency to distribute noise and vibrations, which may effect the operation of the equipment to be
cooled.
In addition, floor-based and other existing cooling systems have a rather limited cooling-
capability. For instance, existing cooling systems have heat densities of approximately 80 watts per
square foot (w/ft2) with planned cooling systems being claimed to possess heat densities of up to
150 w/ft2. Cooling systems having such heat densities, however, may not effectively cool today's
equipment, such as state-of-the-art computational equipment.
As is readily apparent, if equipment is not effectively cooled, the internal temperature of the
electronic components in the equipment substantially increases, thereby leading to significantly
reduced system performance and, in some cases, total system failure. If a cooling system
inefficiently cools the equipment, either the equipment may fail due to increased operating
temperature or the costs for cooling the equipment may be unnecessarily high. What is needed, then,
is a cooling system having its cooling characteristics closely tailored to the heating characteristics
of the equipment to be cooled.
SUMMARY OF THE INVENTION
The present invention overcomes the above-discussed shortcomings and satisfies a
significant need for a cooling system for cooling a heat generating object. In accordance with a first
embodiment of the present invention, a cooling system includes a frame and a heat exchanger, such

as a cooling coil, connected thereto so that airflow is capable of passing through
the frame in proximity to the heat exchanger. A fan unit is connected to the
frame adjacent to the heat exchanger so that when the fan unit is activated, a
first path of airflow passes through the frame in proximity to the heat exchanger
through a first portion of the heat exchanger in a first direction and a second path
of airflow passes through a second portion of the heat exchanger in a second
direction substantially opposite said first direction. In addition, the fan unit is
selectively adjustable along the heat exchanger so that the first and second
paths of airflow may be repositioned to the desired locations along the heat
exchanger and thus the heat generating object. The present invention thus
provides a cooling system that is selectively customized to particular cooling
requirements.
The operation of the embodiment of the present invention includes
drawing air from the heat generating object through the first portion of the heat
exchanger so as to define the first path of air flow. The fan unit draws air from
the first path of airflow through the second portion of the heat exchanger and
directs the drawn air toward the heat generating object in the second path of
airflow. In the event heat generating dynamics of the heat generating object
changes, the fan unit may be moved along the heat exchanger so that the first
and second paths of airflow may be redefined.

BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the system and method of the
present invention may be obtained by reference to the following Detailed
Description when taken in conjunction with the accompanying Drawings wherein:
Figure 1 is a side elevational view of a cooling system in association
with heat generating equipment, in accordance with an embodiment of the
present invention;
Figure 2 is a bottom plan view of the cooling system of Figure 1;
Figure 3 is a bottom plan view of a fan unit of the cooling system of
Figure 1;

Figure 4 is a side elevational view of the fan unit of Figure 3 taken along line B-B thereof;
Figure5 isaside elevational view of a portion of the cooling system of Figure 1 taken along
the A-A line therein;
Figure 6 is an operational diagram of the cooling system of Figure 1 in association with heat
generating equipment;
Figure 7 is another operational diagram of the cooling system of Figure 1 in association with
heat generating equipment;
Figure 8 is a bottom plan view of a plurality of cooling systems of Figure 1 illustrating a
modular aspect thereof; and
Figure 9 is a side elevational view of a cooling system in association with heat generating
equipment, in accordance with another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EXEMPLARY EMBODIMENTS
The present invention will now be described more fully hereinafter with reference to the
accompanying drawings in which a preferred embodiment of the invention is shown. This invention
may, however, be embodied in many different forms and should not be construed as being limited
to the embodiment set forth herein. Rather, the embodiment is provided so that mis disclosure will
be thorough and complete, and will fully convey the scope of the invention to those skilled in the
art.
Referring to Figures 1-8, there is shown a cooling system 1 according to an embodiment of
the present invention. Cooling system 1 is adapted to provide cooled air to one or more heat
generating objects, such as a computer equipment C. As shown in Figure 1, cooling system 1 may

be disposed above the heat generating objec(s) C cooling system 1 is intended to cool. As such,
cooling system 1 may be attached along or suspended from a ceiling of the room in which the heat
generating object C is located.
Cooling system 1 includes, at least one heat exchanger 2 through which a coolant fluid is
passed. Heat exchanger 2 may be a cooling coil or other comparable device. Air is cooled by being
directed through or in proximity to heat exchanger 2. According to the embodiment of the present
invention shown in Figure 2, heat exchanger 2 is sized so that a length 1 and width w thereof are
substantially larger than a height of heat exchanger 2. In this way, a sizeable amount of air is
capable of passing in a transverse (vertical) direction through or in proximity to heat exchanger 2
and cooled thereby. Heat exchanger 2 includes an inlet 2A and an outlet 2B for receiving and
discharging coolant, respectively. Coolant temperature and flow rate within heat exchanger 2 may
be controlled manually or automatically.
Cooling system 1 further includes a frame member 3 to which heat exchanger 2 is attached.
Frame member 3 is utilized for connecting various components of cooling system 1, as explained
below. Cooling system 1 may be attached to or suspended from a ceiling or other object by
connecting frame member 3 thereto. Frame member 3 may include fins 3A to facilitate air flow in
a direction normal to heat exchanger 2.
Cooling system 1 may be modular so that a plurality of cooling systems 1 may be positioned
adjacent each other along a ceiling and/or above one or more heat generating objects C. In
particular, frame member 3 may be shaped to engage with and/or securely attach to a frame member
3 of another cooling system 1. As shown in Figure 8, frame member 3 may be shaped so that
multiple cooling systems 1 may be positioned substantially flush against each other. In this way,
an array or matrix of cooling systems 1 may effective cool an enlarged room having heat generating
equipment C.

Cooling system 1 includes one or more fan units 4 that connect to frame member 3 adjacent
heat exchanger 2. Each fan unit 4 draws air through heat exchanger 2 when activated. Fan units 4
occupy only a portion of the surface of heat exchanger 2, as shown by the bottom plan view of
cooling system 1 (Figure 2). In this way, heated air from heating object C may be drawn through
a first portion 2C of heat exchanger 2 and cooled thereby, drawn through a second portion 2D of heat
exchanger 2 by fan units 4 and thereupon directed towards heating object C. Each fan unit 4
may include one or more fans 40. The operating speed of fans 40 may be fixed, manually varied
or automatically varied to provide the desired cooling capacity. Although each fan unit 4 is shown
as including four fans 40 (Figure 3), it is understood that the number of fans 40 in each fan unit 4
may vary depending upon the operating requirements of cooling system 1.
Each fan unit 4 includes a bracket or flange member 41 that extends from opposed end
panels thereof (Figures 3 and 4). In accordance with an embodiment of the present invention, each
bracket member 41 includes a substantially L-shaped member 42 (Figure 5), one side of which is
secured to an end portion of fan unit 4. Bracket member42 may further include h diagonal support
member 43 connected between the sides of L-shaped member 42 so as to strengthen bracket member
41 and prevent deformation of L-shaped member 42. Bracket members 41 selectively engage with
frame member 3 for connecting fan unit 4 thereto, as discussed in greater detail below.
A hood assembly 5 is connected to frame member 3 and positioned substantially entirely
over heat exchanger 2 so as to define and area A therewithin, as shown in Figure 1. When cooling
system 1 is positioned over a heat generating object C, heated air generated therefrom is collected
within area A through a portion of heat exchanger 2 that is not adjacent a fan unit 4, such as first
portion 2C (Figure 2). The collected air within area A is subsequently drawn by fan units 4 through
a portion of heat exchanger 2 that is adjacent fan unit 4, such as second portion 2D, and directed
towards heat generating object C. By heat exchanger 2 cooling the air as it is collected into hood
assembly 5 and subsequently discharged therefrom, the twice cooled air is recirculated around heat
generating object C so as to maintain operating temperatures thereof within a desired temperature
range.

In a first embodiment of the present invention, hood assembly 5 is dome-shaped or otherwise
includes tapered end portions, as shown in Figure 1. It is understood, however, that hood assembly
5 may have other shapes.
Cooling system 1 is preferably dimensioned so that cooling system 1 unobtrusively hangs
from a ceiling or other structure, without interfering with objects or persons underneath cooling
system 1. By way of one example, the combined height of hood assembly 5 and frame member
3/heat exchanger 2 is approximately 18". It is understood, that the dimensions of cooling system 1,
including the height thereof, may vary.
Because the thermal characteristics of heat generating object C may vary over time, such as
by moving heat generating object C relative to cooling system 1 or adding equipment to or removing
equipment from heat generating object C, it is advantageous to modify the cooling and/or operating
characteristics of cooling system 1 accordingly. According to an embodiment of the present
invention, cooling system 1 allows fan units 4 to be selectively repositioned along the surface of heat
exchanger 2 nearest heat generating object C. In particular, frame member 3. includes one or more
tray or shelf members 6 (Figure 2) that are disposed substantially entirely along opposed end
portions of frame member 3. Tray member 6 extends below heat exchanger 2 and is sized to receive
fan units 4 therein. Fan units 4 may be disposed within tray member 6 at any of a plurality of
locations substantially entirely along frame member 3 and/or tray member 6 thereof. In this way,
fan units 4 are independently positionable along tray member 6/frame member 3. Figure 8 illustrates
fan units 4 of each cooling system 1 being separated from each other. By separating fan units 4 from
each other, the second portion 2D of heat exchanger 2 to which fan units 4 are adjacent may be split
into a plurality of spaced-apart portions.
Referring to Figure 5, each tray member 6 includes an extension member 7 that extends from
frame member 3 and a ledge member 8 that extends from the unconnected end of extension member
7 in a substantially perpendicular relation thereto. Extension member 7 and ledge member 8 form
a shelf upon which the outwardly extending portion of bracket member 41 rests so as to attach fan

unit 4 to frame member 3. A bulbous shaped engagement member 9 may be disposed on an inner
surface of ledge member 8 for supporting bracket member 41 of fan unit 4 so as to provide stability
and particularly to prevent fan unit 4 from vibrating relative to frame member 3.
It is understood that fan units 4 may attach to frame member 3 in ways other than by
engagement between bracket member 41 and tray member 6. For instance, fan units 4 may be
removably attached to frame member 3 using screws, nuts and bolts, or clamp mechanisms.
As stated above, coolant is passed through heat exchanger 2 so that air passing in proximity
to heat exchanger 2 is cooled thereby. Inlet 2A of heat exchanger 2 is positioned above outlet 2B
so that coolant from a cooling source (not shown) is initially forced through the portion of the heat
exchanger 2 closer to hood assembly 5 and thereafter returned to outlet 2B through the portion of
the heat exchanger 2 that is closer to heat generating object C. Noting that the cooler portion of heat
exchanger 2 is the portion thereof that receives the coolant, heated air that is (drawn into hood
assembly 5 remains cooler due to having more recently passed through the cooler portion of heat
exchanger 2.
Cooling system 1 may be disposed within a room so as to cool heat generating objects
therein. In this regard, it is understood that cooling system 1 may be sized for substantially
occupying the ceiling of the room. Alternatively, a plurality of cooling systems 1 may be adjacent
each other along the ceiling. In this way, a plurality of fan units 4 from the cooling systems 1 may
be positioned to be in proximity to each air intake of the heat generating objects C in the room.
The operation of cooling system 1 will be described with reference to Figures 6 and 7.
Initially, fan units 4 are positioned within tray member 6 of frame member 3 so as to be adjacent the
desired portion 2D of heat exchanger 2. It-is understood that fan units 4 may be positioned adjacent
each other (as shown) or separated from each other so that a plurality of second portions 2D of heat
exchanger 2 exist. Next, heated air from heat generating object C is drawn therefrom along a first
path of airflow 10 through a first portion 2C of heat exchanger 2 (Figure 6). The heated air naturally

rises from heat generating object C and/or is drawn therefrom, and is collected into area A of hood
assembly 5. The heated air is cooled by heat exchanger 2 a first time as the heated air passes through
the first portion 2C of heat exchanger 2. The cooled air within hood assembly 5 is then drawn
through a second portion 2D of heat exchanger 2 by activated fan units 4 adjacent thereto, and
thereafter directed towards heat generating object C along a second path 11 of airflow. The cooled
air drawn from hood assembly 5 is cooled a second time by heat exchanger 2 as the air passes
through the second portion 2D of heat exchanger 2. The twice cooled air effectuates heat generating
object C operating at desired operating temperatures.
In the event it is desired to change the location of the first path of airflow 10 and second path
of airflow 11, such as in response to a change in the heating characteristics of the heat generating
object, the fan units 4 are disconnected from frame assembly 3 by disengaging bracket member 41
of fan unit 4 from tray member 6 of frame assembly 3. Fan units 4 are then re-attached to frame unit
4 along a different portion of tray member 6 so that fan units 4 are adjacent another portion of heat
exchanger 2 other than second portion 2D thereof (Figure 7). Once fan units 4 are repositioned and
activated, air heated by heat generating object C is drawn into and collected in hood assembly 5
along a third path 12 of airflow and through heat exchange 2. The collected air is then drawn from
hood assembly 5 by the repositioned fan units 4, passes through heat exchanger 2 a second time and
is directed towards heat generating objects C along a fourth path 13 of airflow. As a result, the paths
of circulated airflow are selectively redefined by reconfiguring cooling system 1 as desired.
One advantage provided by the cooling system 1 according to the present invention concerns
heat density. The cooling system 1 of the present invention are capable of possessing a heat density
of approximately 200 w/ft2 or more. Relative to existing cooling systems, the cooling system 1 is
more capable of meeting the cooling demands of tomorrow's heat generating equipment.
In a second embodiment of the present invention, cooling system 100 includes fan units 4
that are disposed between heat exchanger 2 and hood assembly 5 (Figure 9). In this embodiment,
tray members 6 are disposed from one end of cooling system 1 to another: Fan units 4 engage with

tray members 6 as described above so that each fan unit 4 is independently positionable along tray
members 6. Fans 40 within fan units 4 are operable to blow air that was previously collected along
airflow paths 20 within hood assembly 5. Fans 40 blow the collected air through heat exchanger 2
and towards heat generating object C along airflow paths 21. The blown air is thus twice cooled by
heat exchanger 2, a first time as the air is being collected and a second time as the air is blown from
fan unit 4.
The invention being thus described, it will be obvious that the same may be varied in many
ways. Such variations are not to be regarded as a departure from the spirit and scope of the
invention, and all such modifications as would be obvious to one skilled in the art are intended to
be included within the scope of the following claims.

1. A system for cooling, comprising:
a frame;
a heat exchanger unit connected to said frame such that air flow is capable
of passing through the frame in proximity to said heat exchanger unit; and
a fan unit connected to the frame adjacent to said heat exchanger unit, a
position of said fan unit along said frame being selectively adjustable so that
when said fan unit is activated, air flow passes through said frame in a first
direction through a first portion of said heat exchanger unit and a second
direction substantially opposite said first direction through a second portion of
said heat exchanger unit.
2. The cooling system as claimed in claim 1, wherein said fan unit is
removably attached to said frame.
3. The cooling system as claimed in claim 1, wherein
said fan unit is provided with a bracket member extending from opposed
ends of said fan unit; and
said frame is provided with at least one tray having a plurality of ledge
members sized so that said bracket members engage therewith when said fan
unit is attached to said frame.

4. The cooling system as claimed in claim 3, wherein each said ledge
member is disposed along opposed sides of said frame.
5. The cooling system as claimed in claim 1, wherein a hood member is
connected to said frame adjacent said heat exchanger units.
6. The cooling system as claimed in claim 5, wherein
said hood member is attached to said frame along a first side thereof;
and
said frame is provided with a tray disposed along a second side
thereof, for selectively receiving said fan unit.
7. The cooling system as claimed in claim 6, wherein said heat exchanger
unit has an inlet and an outlet for receiving and discharging coolant, respectively;
said inlet is disposed relatively near said first side of said frame; and said outlet
is disposed relatively near the second side of said frame.
8. The cooling system as claimed in claim 1, wherein said fan unit
operates to draw air from said heat exchanger unit.
9. The cooling system as claimed in claim 1, wherein said fan unit
comprises a plurality of fan members.

10. The cooling system as claimed in claim 1, comprising:
a plurality of fan units, a position of each fan unit being independently
adjustable along said frame.
11. A method of cooling a heat generating object, comprising the steps of:
passing coolant through a heat exchanger;
drawing air from the heat generating object through a first portion of the
heat exchanger so as to define a first path of air flow;
drawing air that passed through the first portion of the heat exchanger
through a second portion of the heat exchanger so as to define a second path of
air flow; and
selectively moving the first and second paths of air flow relative to the
first and second portions of the heat exchanger, respectively.
12. The method as claimed in claim 11, wherein said step of drawing air
through a second portion of the heat exchanger comprises the step of blowing
air from the second portion of the heat exchanger toward the heat generating
object.
13. The method as claimed in claim 12, wherein said step of blowing air
comprises the step of operating a fan unit so that air is drawn from the second
portion of the heat exchanger.

14. The method as claimed in claim 13, wherein said step of selectively
moving comprises the step of moving the fan unit along a surface of the heat
exchanger.
15. An apparatus for cooling a heat generating object, comprising:
a heat exchanger; and
a fan unit operably associated with said heat exchanger so that a first
path of air flow is drawn from said heat generating object through a first portion
of said heat exchanger and a second path of air flow is directed towards said
heat generating object through a second portion of said heat exchanger, said fan
unit being selectively repositioned along said heat exchanger so as to redefine
the first and second paths of flow relative to the first and second portions of said
heat exchanger, respectively.
16. The apparatus as claimed in claim 10, comprising a frame assembly to
which said heat exchanger is attached and said fan unit is removably attached
adjacent said heat exchanger.
17. The apparatus as claimed in claim 16, comprising a hood assembly
attached to said frame assembly so as to receive air from said first path of air
flow and redirect the air towards said second path of air flow.

18. The apparatus as claimed in claim 17, wherein said hood assembly is
substantially dome shaped.
19. The apparatus as claimed in claim 17, wherein said hood assembly has
tapered corner portions.
20. The apparatus as claimed in claim 16, wherein said frame assembly is
provided with a tray portion disposed along the frame assembly and sized for
removably receiving said fan unit therein.
21. The apparatus as claimed in claim 20, wherein said fan unit is provided
with a plurality of bracket members disposed outwardly from opposed end
portions of said fan unit which engage with said tray portion of said frame
assembly.
22. The apparatus as claimed in claim 21, wherein said tray portion
comprises a plurality of shelf members disposed along opposed edges of said
frame assembly; and said bracket members of said fan unit engage with said
shelf members when said fan unit is received in said tray assembly.
23. The apparatus as claimed in claim 20, wherein said fan unit engages
with said tray portion at any of a plurality of locations along said frame assembly.

24. The apparatus as claimed in claim 16, wherein said frame assembly is
sized so that a plurality of said apparatuses may be disposed adjacent each
other in substantially flush engagement therewith.
25. The apparatus as claimed in claim 15, comprising a plurality of fan
units, each fan unit being selectively and individually repositioned along said
heat exchanger so as to redefine the first and second paths of air flow relative to
the first and second portions of said heat exchanger, respectively.

26. The apparatus as claimed in claim 15, wherein said fan unit
comprises a plurality of fans.
27. The apparatus as claimed in claim 15, wherein said fan unit is disposed
adjacent said heat exchanger and blows air away therefrom when activated
28. The apparatus as claimed in claim 15, comprising a hood assembly
attached to said frame assembly so as to receive air from said first path of air
flow and redirect the air towards said second path of air flow;
wherein said heat exchanger has an inlet for receiving coolant and an
outlet for discharging coolant, said inlet being positioned between said hood
assembly and said outlet.
29. The apparatus as claimed in claim 15, wherein said heat exchanger
comprises at least one cooling coil.

A cooling system (1) for cooling a heat generating object (C), comprises:
a frame (3);
a heat exchanger unit (2) connected to the frame (3) such that air flow is
capable of passing through the frame in proximity to said heat exchanger unit
(2); and
a fan unit (4) connected to the frame (3) adjacent to the heat exchanger
unit (2), position of the fan unit (4) along the frame (3) being selectively
adjustable so that when said fan unit (4) is activated, air flow passes through
said frame (3) in a first direction through a first portion of the heat exchanger unit
(2) and a second direction substantially opposite the first direction through a
second portion of the heat exchanger unit (2).

Documents:

91-KOLNP-2003-FORM 27.pdf

91-KOLNP-2003-FORM-27.pdf

91-kolnp-2003-granted-abstract.pdf

91-kolnp-2003-granted-assignment.pdf

91-kolnp-2003-granted-claims.pdf

91-kolnp-2003-granted-correspondence.pdf

91-kolnp-2003-granted-description (complete).pdf

91-kolnp-2003-granted-drawings.pdf

91-kolnp-2003-granted-examination report.pdf

91-kolnp-2003-granted-form 1.pdf

91-kolnp-2003-granted-form 18.pdf

91-kolnp-2003-granted-form 3.pdf

91-kolnp-2003-granted-form 5.pdf

91-kolnp-2003-granted-gpa.pdf

91-kolnp-2003-granted-specification.pdf

91-kolnp-2003-granted-translated copy of priority document.pdf


Patent Number 226796
Indian Patent Application Number 91/KOLNP/2003
PG Journal Number 52/2008
Publication Date 26-Dec-2008
Grant Date 24-Dec-2008
Date of Filing 23-Jan-2003
Name of Patentee LIEBERT CORPORATION
Applicant Address 1050 DEARBORN DRIVE, COLUMBUS, OHIO
Inventors:
# Inventor's Name Inventor's Address
1 LENNART STAHL 1717 POINCIANA LANE PLANO, TX 75075
2 BELADY CHRISTIAN 2202 AMHERST CIRCLE, MCKINNEY, TX 75070
PCT International Classification Number F 28 F 27/02
PCT International Application Number PCT/US01/22398
PCT International Filing date 2001-07-17
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 09/617,391 2000-07-17 U.S.A.