U.S. patent application number 09/761984 was filed with the patent office on 2001-08-02 for column fan unit.
Invention is credited to Akhtar, Salman, Han, Ming Hui.
Application Number | 20010011007 09/761984 |
Document ID | / |
Family ID | 46257435 |
Filed Date | 2001-08-02 |
United States Patent
Application |
20010011007 |
Kind Code |
A1 |
Akhtar, Salman ; et
al. |
August 2, 2001 |
Column fan unit
Abstract
An air handling system for use in a building is used in
combination with an elevated floor assembly for mounting on a
principal floor of the building, this assembly including a working
area floor which lies above the principal floor so as to provide an
air plenum between the two floors. An outlet attenuator is mounted
on the principal floor and extends upwardly through the working
area floor, this attenuator including an exterior outlet housing
having an air inlet at the top and a lowermost air outlet in at
least one vertical side thereof. The air outlet is connected to the
air plenum and is connected to the air inlet by a lower airflow
passageway defined by interior walls. This attenuator includes
sound absorbing material contained in the housing. An axial or
centrifugal fan unit is mounted above the outlet attenuator and
provides a downward flow of air to the outlet attenuator. There is
also an inlet attenuator section mounted above the fan unit and
extending upwardly to a ceiling of the building. The inlet
attenuator has an exterior housing with an upper air inlet and a
circular bottom air outlet. The inlet attenuator in one preferred
embodiment includes an elongate airflow member mounted centrally in
the airflow passageway that extends between the air inlet and air
outlet. In another version, the inlet attenuator has its airflow
passageway divided into two passageways by a conical divider
wall.
Inventors: |
Akhtar, Salman;
(Mississauga, CA) ; Han, Ming Hui; (Mississauga,
CA) |
Correspondence
Address: |
Gifford, Krass, Groh, Sprinkle,
Patmore, Anderson & Citkowski
280 North Woodward Avenue, Suite 400
Birmingham
MI
48009
US
|
Family ID: |
46257435 |
Appl. No.: |
09/761984 |
Filed: |
January 17, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09761984 |
Jan 17, 2001 |
|
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|
09491904 |
Jan 27, 2000 |
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Current U.S.
Class: |
454/338 ;
454/906 |
Current CPC
Class: |
F24F 7/007 20130101;
F24F 13/24 20130101; Y10S 454/906 20130101 |
Class at
Publication: |
454/338 ;
454/906 |
International
Class: |
F24F 007/007 |
Claims
I claim:
1. An air handling system for use in a multiple story building in
order to supply air to one level of said building, said system
comprising: an outlet attenuator adapted for mounting on a floor of
said building and including an exterior outlet housing having an
air inlet in a top thereof and a lowermost air outlet in at least
one vertical side thereof, said air inlet and air outlet being
connected by a lower airflow passageway defined by interior walls
of said outlet attenuator, said outlet attenuator further including
sound absorbing material which is contained in said housing and
extends to and is covered by said interior walls; a fan unit
mounted above said outlet attenuator and capable of providing
downward airflow into said air inlet of the outlet attenuator; and
a fan inlet section mounted above said fan unit and extending
upwardly therefrom, said inlet section including an exterior inlet
housing with a bottom air outlet in a bottom end thereof and an
upper airflow passageway that extends downwardly to said bottom air
outlet, wherein said bottom air outlet is positioned directly above
an airflow inlet of said fan unit.
2. An air handling system according to claim 1 wherein said fan
unit includes an axial fan having a vertical axis of rotation.
3. An air handling system according to claim 2 wherein said fan
inlet section includes a central elongate airflow member mounted
centrally in said upper airflow passageway and having a vertical
longitudinal axis, and wherein said elongate airflow member
contains sound absorbing material.
4. An air handling system according to claim 3 wherein said
elongate airflow member includes an outer peripheral wall that is
made of perforated sheet metal and that diverges outwardly from an
upper end to a bottom end thereof.
5. An air handling system according to claim 3 wherein said air
inlet section further includes two or more intermediate airflow
members mounted in said upper airflow passageway and spaced from
said central elongate airflow member and from internal walls
defining an outer periphery of said upper airflow passageway, each
of said intermediate airflow members being tapered inwardly in a
downwards direction from an upper end section thereof.
6. An air handling system according to claim 5 wherein each of said
intermediate airflow members includes inner and outer peripheral
walls that are made of perforated sheet metal and sound absorbing
material contained between said inner and outer peripheral
walls.
7. An air handling system according to claim 1 wherein said fan
inlet section is a sound attenuator and contains sound absorbing
material positioned behind perforated interior walls of said fan
inlet section and said fan inlet section includes at least one heat
exchanging coil unit arranged so that incoming airflow passes
through said at least one coil unit.
8. An air handling system according to claim 7 wherein said fan
inlet section includes a central elongate airflow member mounted
centrally in said upper airflow passageway and having a vertical
longitudinal axis, and wherein said elongate airflow member
contains sound absorbing material.
9. An air handling system according to claim 4 wherein said fan
inlet section includes two or more side inlet openings and a top
inlet opening, said side inlet openings being adapted to receive
return air from an interior region of said one level of the
building and said top inlet opening adapted to receive fresh
incoming air from a location outside said one level of the
building.
10. An air handling system according to claim 3 wherein said
lowermost air outlet is provided in at least three vertical sides
of said exterior outlet housing and said lower airflow passageway
curves through approximately 90 degrees form said air inlet to the
lowermost air outlet in each of said at least three vertical
sides.
11. An air handling system for use in a building in order to supply
an air mixture to said building, said system comprising, in
combination: an air outlet and sound attenuator section adapted for
mounting on a floor of said building and including an outlet
housing containing sound absorbing material and having a lower
airflow passageway extending vertically through said outlet housing
to a lowermost air outlet located in at least one vertical side
thereof, a fan unit mountable above said air outlet and sound
attenuator section and capable of providing downward airflow into
said lower airflow passageway; and an air inlet and sound
attenuator section mounted above said fan unit and including an
inlet housing with a round bottom air outlet in a bottom end
thereof and an upper airflow passageway that tapers inwardly in a
downwards direction and that extends downwardly to said bottom air
outlet, said upper airflow passageway being surrounded on
vertically extending sides thereof with sound absorbing material,
said inlet housing having at least first and second air inlet
openings found in an upper section thereof, said first air inlet
opening adapted to receive fresh incoming air and at least said
second air inlet opening adapted to receive return air from said
building, wherein, during use of said air handling system, said
fresh incoming air and said return air are mixed in said air inlet
and sound attenuator section and a mixed airflow as delivered by
said upper airflow passageway to an inlet of said fan unit.
12. An air handling system according to claim 11 wherein said fan
unit is an axial fan unit having a vertical axis of rotation and
said inlet housing has perforated interior walls made of sheet
metal and forming said vertically extending sides of said upper
airflow passageway.
13. An air handling system according to claim 12 wherein said air
inlet and sound attenuator section includes at least one heat
exchanging coil unit arranged in at least one of said air inlets so
that incoming air passes through said coil unit.
14. An air handling system according to claim 12 wherein said air
inlet and sound attenuator section includes a central elongate
airflow member mounted centrally in said upper airflow passageway
and having a vertical longitudinal axis, and wherein said elongate
airflow member contains sound absorbing material.
15. An air handling system according to claim 14 wherein said
elongate airflow member includes an outer peripheral wall that is
made of perforated sheet metal and that diverges outwardly from an
upper end to a bottom end thereof.
16. An air handling system according to claim 14 wherein said air
inlet and sound attenuator section further includes two or more
intermediate airflow members rigidly mounted in said upper airflow
passageway and spaced from said central elongate airflow member and
from said vertically extending sides of the upper airflow
passageway, each of said intermediate airflow members being tapered
inwardly in a downwards direction from an upper end section
thereof.
17. An air handling system according to claim 16 wherein said
lowermost air outlet is provided in at least three vertical sides
of said outlet housing and said lower airflow passageway curves
through approximately 90 degrees from an air inlet at a top of said
outlet housing to said lowermost air outlet in each of said at
least three vertical sides.
18. An air handling system according to claim 14 including an
acoustical resonator mounted at a bottom end of said elongate
airflow member and located adjacent said fan unit.
19. An air handling system for use in a building in order to supply
treated air to said building, said system comprising: an air outlet
and sound attenuator section adapted for mounting on a floor of
said building and including an outlet housing containing sound
absorbing material and having a lower airflow passageway extending
vertically through said outlet housing to a lowermost air outlet
located in at least one vertical side thereof, a fan unit mountable
above said air outlet and sound attenuator section and capable of
providing downward airflow into said lower airflow passageway, and
an air inlet and sound attenuator section mounted above said fan
unit and including an inlet housing with a round bottom air outlet
in a bottom end thereof and an upper airflow passageway that tapers
inwardly in a downwards direction and that extends downwardly to
said bottom air outlet, said upper airflow passage being surrounded
on vertically extending sides thereof with sound absorbing
material, an upper section of said inlet housing having an air
inlet opening provided in two or more of said vertically extending
sides, said upper airflow passageway being divided into at least
two smaller passageways, that extend from said air inlet opening to
said bottom air outlet, by means of a substantially conical divider
wall which is substantially coaxial with said upper airflow
passageway; and at least one heat exchanging coil unit mounted in
said air inlet and sound attenuator section for heating or cooling
at least a portion of the airflow entering said system through said
air inlet opening.
20. An air handling system according to claim 19 wherein said upper
airflow passageway is defined by upper and lower interior walls
which are made of perforated sheet metal and each of which has a
substantially conical shape and is substantially coaxial with said
divider wall.
21. An air handling system according to claim 20 wherein sound
absorbing material fills a conical space formed by said upper
interior wall and said fan unit includes an axial fan with a
vertical axis of rotation.
22. An air handling system according to claim 21 wherein said
divider wall is made of non-perforated sheet metal and has a
circular bottom end at said bottom air outlet.
23. An air handling system according to claim 19 wherein said
divider wall is made with two, spaced-apart sheet metal walls, each
having a substantially conical shape and sound absorbing material
filling a space between said two sheet metal walls.
24. An air handling system according to claim 23 wherein one of
said two sheet metal walls is perforated and has an outer airflow
defining surface, which faces substantially downwardly and radially
outwardly.
25. An air handling system according to claim 19 wherein there are
two or more heat exchanging coil units covering all sides of said
air inlet opening so that all of the airflow entering said system
is required to pass through the heat exchanging coil units.
Description
[0001] This is a continuation-in-part application of U.S. patent
application Ser. No. 09/491,904 filed Jan. 27, 2000.
BACKGROUND OF THE INVENTION
[0002] This invention relates to air handling systems for use in a
building in order to supply air to the interior of a building and,
in particular, to such a system employing an axial fan unit.
[0003] A number of different air handling systems are known for
providing conditioned air to a building's interior. These systems
can vary depending upon the size of and requirements of the
building. They also differ on the basis of the perceived
requirements for heating and cooling in the building. Particularly
in systems designed for larger buildings, a concern of the building
owner and of the users of the building is that the air handling
system be not only efficient for the delivery of conditioned air to
each floor of the building but also relatively quiet in its
operation.
[0004] Relatively sophisticated air handling systems for
multi-storey buildings are already known in the heating and air
conditioning industry. For example, it is already known to provide
a relatively large axial fan on a lower floor of a multi-storey
building in order to deliver the required conditioned air through a
system of air ducts to the various floors of the building. In order
to reduce the sound levels that are produced by the operation of
the fan, the fan inlet can be mounted adjacent an inlet attenuator
which directs incoming air into the inlet side of the fan. There
can also be an outlet attenuator mounted adjacent the outlet side
of the fan and connected to one or more air delivery ducts. Both of
these attenuators can have exterior walls and specially designed
interior walls with sound attenuating material arranged between the
interior and exterior walls. One perceived difficulty with these
known system is that they generally require a reasonably large room
set aside on the lower floor for the air handling system, including
the attenuators and, with such systems, difficulties can be
encountered in controlling the conditioned air delivered to each
floor of the multi-storey building and in modifying the air
delivery system when changes, are made to the layout of one or more
of the floors of the building.
[0005] In U.S. Pat. No. 4,418,788 issued Dec. 6, 1983 to Mitco
Corporation there is disclosed a composite branch take-off and
silencer for an air distribution system. This take-off unit
includes two series-coupled sections including a static pressure
regain section and a channel section adapted for coupling an input
duct to an output duct and branch ducts. With this unit, the input
section is located adjacent the axial fan which is generally
located at the bottom end while the channel section which is
coupled to a main duct for the delivery of air is located in the
upper half of the unit. Sound absorbing material is used at several
locations in the unit to reduce the amount of sound passing through
the unit and into the air ducts.
[0006] More recent U.S. Pat. No. 4,874,127 issued Oct. 17, 1989 to
W. R. Collier describes a multi-level access flooring system with a
working area floor and at least one intermediate floor. A
horizontal plenum is formed between an intermediate floor and the
building floor. An HVAC unit is mounted on an elevated top floor
and this unit has an axial fan and an air outlet located at the
bottom thereof. Just above the outlet are arranged evaporator
coils. Air from the room enters the HVAC unit through a top grill.
As there is no provision for reducing the sound levels emanating
from the axial fan, it appears that the climate control system
described in this patent specification would be relatively noisy.
There is also no provision in this system for mixing fresh air with
return air before it is passed through the HVAC unit and delivered
to the air distribution plenum and the air outlets.
[0007] U.S. Pat. No. 4,646,966 issued Mar. 3, 1987 to Argon Corp.
teaches a personalized air conditioning system which employs an air
plenum formed by an elevated floor of the building. Air rises from
the floor space into an air distribution system which includes an
upstanding passageway or column that has upright sidewalls. A small
fan is mounted in the column as is an air valve which apparently
regulates the air passing upwardly in the column. A plurality of
air outlets are provided near the top of the column and are
adjustable.
[0008] It is an object of the present invention to provide an
efficient air handling system that can be provided on each floor of
a building, particularly a high-rise building, in order to supply
air to the interior.
[0009] It is a further object of the present invention to provide a
novel air handling system for use in a building having an elevated
floor assembly mounted on a principal floor of the building, this
assembly including a working area floor which lies above the
principal floor so as to provide an air plenum.
[0010] It is another object of the present invention to provide an
air handling system for use in a building, the system including an
air outlet section with a lowermost air outlet, an axial fan unit
and an air inlet section that is mounted above the axial fan unit
and that has an air mixing chamber arranged to receive airflows
entering through air inlet openings.
SUMMARY OF THE INVENTION
[0011] According to one aspect of the invention, an air handling
system for use in a building in order to supply air to the interior
thereof comprises, in combination, an elevated floor assembly for
mounting on a principal floor of the building, an outlet attenuator
for mounting on this principal floor, an axial fan unit mounted
above the outlet attenuator, and an inlet attenuator section
mounted above the axial fan unit. The floor assembly includes a
working area floor which in use lies above and is spaced apart from
the principal floor so as to provide an air plenum between the
principal floor and the working area floor. The outlet attenuator
is adapted to extend upwardly through the working area floor. This
attenuator includes an exterior outlet housing having a lower air
inlet in the top thereof and a lowermost air outlet in at least one
vertical side thereof. The lowermost air outlet is connected to the
air plenum during use of the system and is connected to the lower
air inlet by a lower air flow passageway defined by interior walls
of the attenuator. The outlet attenuator further includes sound
absorbing material contained in the housing that extends to and is
covered by the interior walls. The axial fan unit is capable of
providing downward air flow into the lower air inlet of the outlet
attenuator. The inlet attenuator extends upwardly to a ceiling of
the building during use of the system. This attenuator includes an
exterior inlet housing having an upper air inlet in an upper region
thereof and a bottom air outlet in a bottom side thereof. The
bottom air outlet is connected to a top inlet of the axial fan
unit. The inlet attenuator section further includes sound absorbing
material contained in the inlet housing and interior walls forming
an upper airflow passageway extending from the upper air inlet to
the bottom air outlet.
[0012] Preferably, the inlet attenuator section includes air filter
panels mounted in the inlet housing and arranged so that all
airflow through the upper airflow passageway during use of this
system is required to flow through the air filter panels.
[0013] According to another aspect of the invention, an air
handling system for use in a multi-storey building in order to
supply air to a level of the building comprises an outlet
attenuator adapted for mounting on a floor of the building, a fan
unit mounted above the outlet attenuator and a fan inlet section
mounted above the fan unit. The outlet attenuator includes an
exterior outlet housing having an air inlet in the top thereof and
a lowermost air outlet in at least one vertical side thereof. The
air inlet and the air outlet are connected by a lower airflow
passageway defined by interior walls. The outlet attenuator further
includes sound absorbing material which is contained in the housing
and extends to and is covered by the interior walls. The fan unit
is capable of providing downward air flow into the air inlet of the
outlet attenuator. The fan inlet section extends upwardly from the
fan unit and includes an exterior inlet housing with a bottom air
outlet in a bottom end thereof and an upper airflow passageway that
extends downwardly to the bottom air outlet. The bottom air outlet
is positioned directly above the air flow inlet of the fan
unit.
[0014] Preferably the fan inlet section is a sound attenuator and
contains sound absorbing material positioned behind perforated
interior walls. In a particularly preferred embodiment, the fan
inlet section includes a central elongate airflow member mounted
centrally in the upper airflow passageway and having a vertical
longitudinal axis. This airflow member also contains sound
absorbing material.
[0015] According to another aspect of the invention, an air
handling system for use in building in order to supply an air
mixture to the building comprises, in combination, an air outlet
and sound attenuator section adapted for mounting on a floor of the
building, a fan unit mountable above the air outlet section, and an
air inlet and sound attenuator section mounted above the fan unit.
The outlet section includes an outlet housing containing sound
absorbing material and a lower airflow passageway extending
vertically through the outlet housing to a lowermost air outlet
located in at least one vertical side thereof. The fan unit is
capable of providing downward airflow into the lower airflow
passageway. The air inlet and sound attenuator section includes an
inlet housing with a round bottom air outlet in the bottom end
thereof and an upper airflow passageway that tapers inwardly in a
downwards direction and extends downwardly to the bottom air
outlet. The upper airflow passageway is surrounded on vertically
extending sides thereof with sound absorbing material. The upper
airflow passageway is connected so as to deliver a mixed airflow to
an inlet of the fan unit. The inlet housing has first and second
air inlet openings formed in an upper section thereof. The first
air inlet opening is adapted to receive fresh incoming air and at
least the second air inlet opening is adapted to receive return air
from the building. During use of the system, the fresh incoming air
and the return air are mixed in the air inlet and sound attenuator
section.
[0016] According to still another aspect of the invention, an air
handling system for use in a building in order to supply treated
air to the building comprises an air outlet and sound attenuator
section adapted for mounting on a floor of the building and
including an outlet housing containing sound absorbing material and
having a lower airflow passageway extending vertically through the
outlet housing to a lowermost air outlet located in at least one
vertical side thereof; a fan unit mountable above the air outlet
section and capable of providing downward airflow into the lower
airflow passageway, and an air inlet and sound attenuator section
mounted above the fan unit and including an inlet housing. This
housing has a round bottom air outlet in a bottom end thereof and
an upper airflow passageway that tapers inwardly in a downwards
direction and that extends downwardly to the bottom air outlet. The
upper airflow passage is surrounded on vertically extending sides
thereof with sound absorbing material. An upper section of the
inlet housing has an air inlet opening provided in two or more of
the vertically extending sides. The upper airflow passageway is
divided into at least two smaller passageways, that extend from the
air inlet opening to the bottom air outlet, by means of a
substantially conical divider wall which is substantially coaxial
with the upper airflow passageway. There is also at least one heat
exchanging coil unit mounted in the air inlet and sound attenuator
section for heating or cooling at least a portion of the airflow
entering the system through the air inlet opening.
[0017] Further features and advantages will become apparent from
the following detailed description taken in conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a side elevation of an air handling system
constructed in accordance with the invention;
[0019] FIG. 2 is a side elevation of the air handling unit
including an outlet attenuator, an axial fan unit and an inlet
attenuator with the airflow passageways in the two attenuators
being shown in cross-section and panels removed for illustration
purposes;
[0020] FIG. 3 is a perspective view of the housing that
incorporates the inlet attenuator and in which the axial fan unit
can be mounted;
[0021] FIG. 4 is a perspective view taken from above and to one
side showing the top of the outlet attenuator with the attenuator
separated from the axial fan unit (not shown) and the housing of
FIG. 3;
[0022] FIG. 5 is a plan view showing the top end of the preferred
air handling unit;
[0023] FIG. 6 is a side elevation showing another embodiment of the
air handling unit, the airflow passageways of the two attenuators
being shown in cross-section;
[0024] FIG. 7 is a vertical cross-section taken along the central
axis of another embodiment of the inlet attenuator;
[0025] FIG. 8 is a horizontal cross-section of the inlet attenuator
taken along the line VIII-VIII in FIG. 7;
[0026] FIG. 9 is another horizontal cross-section of the inlet
attenuator taken along the line IX-IX in FIG. 7;
[0027] FIG. 10 is a vertical cross-section taken along the central
axis of a further embodiment of the inlet attenuator; and
[0028] FIG. 11 is a three-dimensional schematic illustration of the
three conical wall members used in the embodiment of FIG. 10.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0029] One version of an air handling system of the present
invention is illustrated generally in FIG. 1. This system includes
a vertically extending or column like air handling unit 10, the
details of which can be seen to a greater extent in FIG. 2. The air
handling system is for use in a building, particularly a
multi-storey building such as an office tower, the system providing
or supplying air to the interior of the building. In particular,
the preferred, illustrated air handling system is intended to
supply conditioned air to one floor level of the multiple storey
building. One or more of the air handling units 10 can be installed
on each floor level of the building, as required. Because these
units are intended to supply air to a single floor level, they can
be made smaller and more compact than would be the case for an air
handling unit designed to supply conditioned air to a complete
multiple storey building.
[0030] The air handling unit 10 is preferably used in combination
with an elevated floor assembly 12 illustrated in part in FIG. 1.
The floor assembly is mounted on a principal floor 14 of the
building which in many cases will be a concrete floor capable of
supporting substantial weight, including the weight of the air
handling unit 10. The floor assembly 12 includes a working area
floor 16 which in use lies above and is spaced apart a distance D
from the principal floor so as to provide an air plenum 18 between
the principal floor 14 and the working area floor 16. It will be
understood that both the principal floor 14 and the working area
floor 16 would normally extend over most of the floor area of the
building at the floor level where the unit 10 is installed. The
floor assembly 12 can be constructed in a variety of known ways and
therefore a detailed description of the floor assembly is deemed
unnecessary herein. For example, it can be constructed in a manner
similar to that illustrated and described in U.S. Pat. No.
4,874,127 issued Oct. 17, 1989 except that there is only one
elevated floor at 16. It can, for example, be made with the use of
horizontally extending floor panels which cover the working area on
which workers move in performing their task and on which equipment
normally used in the room is supported. The panels can be supported
on horizontally extending beams or frame members 20 which are in
turn supported by a plurality of pedestals 22 arranged in a
suitable grid.
[0031] One of the advantages of the air handling system of the
invention is that it is relatively easy to provide a conditioned
air outlet at almost any location on the floor level since the air
plenum 18 extends over substantially all of the floor area. It is
simply necessary to form or provide a suitable air outlet at the
desired location in one of the panels forming the working area
floor 16. It is not necessary to install a new, elongate air duct
to move the conditioned air from the outlet of the air handling
unit 10 to the desired outlet location.
[0032] The air handling unit 10 includes an outlet attenuator 24
which can be mounted on the principal floor 14 and is adapted to
extend upwardly through the working area floor 16 as shown in FIG.
1. In the preferred illustrated embodiment, the outlet attenuator
24 is constructed as a separate section, the height of which is
indicated by H.sub.1 in FIG. 2. The air handling system 10
preferably comprises two major sections, one of which is the outlet
attenuator and the other of which includes a fan unit indicated
generally at 26 and an inlet attenuator section 28. Although the
illustrated, preferred fan unit 26 is an axial fan unit having a
vertical rotation axis, other types of fan units could also be used
with suitable modifications to the inlet and outlet attenuator
sections. For example, a centrifugal fan unit could be used. The
overall height of the second major section is indicated by H.sub.2
in FIG. 2. By splitting the rather high air handling unit 10 into
these two major sections, the unit 10 is easier to handle and to
transport to the floor of the building where it is to be installed.
The second major section that includes the fan unit and the inlet
attenuator is made so as to be mountable on and supported by the
outlet attenuator section, which can also be described as an air
outlet and sound attenuator section 24.
[0033] The air outlet attenuator 24 includes an exterior outlet
housing 30 that is constructed with the use of a box like framework
that includes four upright frame members 32, two of which can be
seen in FIG. 2. Each pair of frame members 32 located on each side
of the unit is rigidly connected to one another by three horizontal
frame members 34, 36 and 38. Covering the outside of the housing 30
are four metal rectangular panels 40, each of which is attached to
the adjacent frame members 32, 36 and 38 by means of suitable
fasteners such as screws or bolts indicated at 42. The gap between
the bottom edge of each panel 40 and the bottom of the outlet
housing can either be open or closed as desired. The unit shown in
FIGS. 1 and 2 has a lowermost air outlet 44 located in the side 46
of the outlet attenuator but it will be appreciated that two, three
or all four sides of the outlet attenuator can be provided with a
rectangular air outlet such as the outlet 44 shown in FIG. 1. Which
sides will have a lowermost air outlet will depend upon the
particular location of the air handling unit in the building and
the airflow requirements of the floor level where the unit is
installed. If one or more of the sides of the outlet attenuator is
to be completely enclosed so that there is no air outlet, each of
these sides can be covered at the bottom end with a rectangular
metal panel similar to the panel 40 but of smaller height. The
outlet attenuator 24 has an air inlet 48 located in a top 50
thereof. The preferred air inlet 48 (herein referred to as the
"lower air inlet") is illustrated in FIG. 4 and it will be seen
that it is an annular air inlet in the center of which is a
circular metal cap 52. This cap is connected to perforated interior
wall 54 by means of four radially extending struts 56. The cap 52
forms the upper end of an inner airflow defining member identified
generally by 58, this member having a substantially funnel-shaped
bottom section 60 that can be seen in FIG. 1 and an elongate
cylindrical upper section 62, the height of which can be seen in
FIG. 2. Interior walls that form these two sections are formed with
perforated sheet metal in a manner known per se in the construction
of air flow attenuators and silencers. As shown in FIG. 2,
preferably a cylindrical metal tube forms the upper section 62 and
extends right down to the bottom end of the outlet attenuator. This
metal tube helps support the conical or funnel shaped bottom
section 60 with the upper ends 64 of the bent, perforated metal
plates that comprise the outer surface of the bottom section being
permanently attached such as by welding to the cylindrical metal
tube.
[0034] The air outlet attenuator 24 includes a second, perforated
interior wall located at 66 and again the upper portion of this
interior wall is cylindrical while the lower portion indicated at
68 is funnel-shaped. The interior walls of the attenuator define a
lower airflow passageway 70 which extends from the lower air inlet
48 to the lowermost air outlet or air outlets 44. The air outlet or
outlets 44 are connected to the air plenum 18 when the unit has
been installed in the manner shown in FIG. 1. Also, in a manner
known per se in the attenuator art, sound absorbing material 72 is
contained in the outlet housing 30 and extends to and is covered by
the interior walls. In particular, the space between the interior
wall 66 and each exterior panel 40 can be filled with this sound
absorbing material and the perforated metal tube that forms the
upper section 62 can be filled with this material as well. Also,
the space 63 between the bottom section of the aforementioned metal
tube and the curved metal panels forming the bottom section 60 can
be filled with this material. Accordingly, it will be appreciated
that any sound that emanates downwardly from the fan unit 26 will
be reduced to a substantial extent by this efficient outlet
attenuator. The inner airflow defining member 58 can be considered
a central airflow guide member with a vertical, cylindrical upper
portion 62 that is coaxial with the axis of rotation of the fan
unit 26. It will be appreciated as well that the cap 52 at the
upper end of this member is aligned with the hub portion of the
axial fan, the rotating fan blades of which are not shown in the
drawings.
[0035] The outlet attenuator 24 is substantially rectangular in
plan view and preferably is substantially square in plan view.
Because these air handling units 10 are designed to be installed
and operated on each floor level of a high-rise building, they can
be made reasonably compact and in fact, if desired, they can be
constructed so as to be similar in size and outer appearance to a
supporting structural column of the building. Preferably each of
the two horizontal dimensions of the air handling unit 10 do not
exceed five feet and the outlet attenuator 24, the axial fan unit
26 and the inlet attenuator section 28 have a combined height of at
last about nine feet and not more than about twelve feet with the
actual selected height depending upon the actual height of the
floor level in which the unit is to be installed. In one
particularly preferred embodiment of the air handling unit 10, the
horizontal dimensions of the unit were only slightly more than four
feet in each direction, measuring fifty-three inches each way. The
total height (H.sub.1 and H.sub.2) of this preferred unit was 111"
or 9 feet 3". The height H.sub.3 of the air outlet 44 as measured
from the bottom end of the unit was ten inches.
[0036] It will be understood that in order to provide for a smooth
air flow from the air handling unit into the air plenum 18, the
interior walls of the outlet attenuator are smoothly curved at
least in the lower section of the attenuator. In the illustrated
preferred embodiment, the airflow passageway 70 curves through
approximately 90.degree. from the air inlet 48 to the one or more
lowermost air outlets 44.
[0037] Turning now to the upper section of the preferred air
handling unit 10, this section also includes a housing that is
generally box like and has four vertical frame members 75 that
extend from the top of the unit to the bottom end of the section at
76. Extending between each adjacent pair of these frame members are
four horizontal connecting frame members 77 to 80. The
aforementioned fan unit 26 is located in the rectangular box
between frame members 77 and 78 while the inlet attenuator section
is located in the space extending from the frame members 78 to the
top frame members 80. The vertical sides of the housing are
preferably covered with generally rectangular metal panels
including the panels 82 and 84 shown in FIG. 1. These panels can be
attached by suitable threaded fasteners such as bolts or screws or,
in the case of any panels that need not be removed, by means of
rivets. For sake of illustration, in FIG. 1, a lower, rectangular
metal panel that would cover the rectangular opening at 86 has been
removed. The illustrated fan unit 26 is located behind this panel
of which there can be as many as four, one on each side. It will be
understood, however, that in actual use of the air handling unit,
all four sides of the fan unit 26 are normally covered by these
metal panels so that the fan unit cannot be seen. The removable
metal panel covering the opening 86 is attached by threaded
fasteners such as screws.
[0038] Turning now to the fan unit 26, the fan unit itself can be
of standard construction except that it is oriented so as to
provide a downward airflow into the air inlet 48 of the outlet
attenuator. The rotating fan blades (not shown) are rotatably
mounted in a cylindrical fan housing 88 which is open at its upper
and lower ends. In order to dampen vibrations from the operation of
the fan, in a known manner the fan housing is mounted on a number
of coil springs 90 which extend between a horizontal platform 92
and support brackets 94. The platform 92 is mounted on four rollers
96 mounted at the bottom end of short, vertical legs 98. The
rollers can roll along two parallel metal tracks 100 which can be
made of elongate angle members. The angle members can be seen
clearly in FIG. 3. These angle members are mounted on horizontal
connecting frames 102, the ends of which are rigidly connected to
two of the frame members 77. It will thus be seen that the fan unit
is mounted in such a way that it can be readily removed from
between the inlet attenuator and the outlet attenuator for
servicing, repairs or replacement. Suitable, known sealing units or
gaskets are provided at each end of the fan housing to close the
gap between the end of the fan housing and the adjacent attenuator
and to prevent the escape of air at the ends of the housing.
[0039] The air inlet and sound attenuator section 28 is mounted
above the fan unit 26 and extends upwardly to a ceiling of the
building during use of this system. It will be understood however
that the top end of the unit located at 105 is normally spaced
below the actual structural ceiling of the building which may
comprise a solid concrete slab (forming the floor of the next
building level). Often a suspended ceiling 106 is formed or
provided below the structural ceiling and it is this ceiling that
is seen by users of the building. This ceiling may comprise rows of
standard ceiling panels supported by suitable support members and
hangers (not shown). In the normal installation of the present air
handling unit, the top of the unit extends through the suspended
ceiling 106 in the manner shown in FIG. 1. This enhances the
appearance of the air handling unit and again can give rise to the
impression that the air handling unit has the appearance of a
standard building column.
[0040] The preferred air inlet and sound attenuator section 28
includes an exterior inlet housing which can simply be the upper
portion of the housing described above that includes frame member
75 and members 77 to 80. The inlet housing has an upper air inlet
108 and a bottom air outlet 110 in a bottom side thereof. The
bottom air inlet 110 is connected to a top inlet of the axial fan
unit 26. Standard sound absorbing material 112 is contained in the
inlet housing, being positioned between perforated interior walls
114 and exterior walls of the housing formed by the aforementioned
panels 84. The interior walls 114 form an upper airflow passageway
116 that connects the upper air inlet to the bottom air outlet
110.
[0041] The preferred inlet attenuator section includes air filter
panels 118 and 120 which can be mounted in rectangular, metal
frames. As illustrated in FIG. 2 and in FIG. 3, these panels are
arranged so that all air flow through the upper airflow passageway
116 during use of the system is required to flow through the air
filter panels. Each generally flat air filter panel can be of
standard construction and therefore a detailed description thereof
herein is deemed unnecessary. In the preferred illustrated
embodiment of FIGS. 2 and 3, the filter panels include the two main
panels sections 118, 120 arranged in a V-shape and located directly
above the upper airflow passageway 116 which is substantially
funnel-shaped. Also, as shown in FIG. 2, the combination of the two
panels sections 118, 120 extends substantially the width of the
inlet attenuator section. Further, each panel section extends
substantially from the front side 122 of the inlet attenuator to
the rear side 124 as seen in FIG. 3. In order to support the air
filter panels, there is an inverted V-shaped support frame 126 that
extends across the top of the upper airflow passageway 116 from the
front side 122 to the rear side 124. The lowermost side edges of
these filter panels can rest against the sloping sides of the frame
126. There are also upper, elongate support frames 128 mounted on
interior walls 130 of the inlet attenuator section. Each of the two
frames 128 extends at an acute angel to the interior wall and
preferably is formed with an upper edge flange 130 which helps to
hold the air filter panel in place. In addition, there can be
arranged along the rear side 124 two further supporting frame
members 132 arranged in a V-shape. The frame members 132 extend
between the support frame 126 and the two support frames 128. The
frames 132 have a bottom flange 134 that extends perpendicularly
from the rear side 124 and on this flange the edge of the filter
panel can be supported.
[0042] It will also be understood that in order for the filter
panels to be maintained or replaced, access to the upper portion of
the attenuator section 28 is provided by means of one or more
removable access panels. Such an access panel can simply be
provided by making one of the rectangular metal panels 82 (see FIG.
1) removable (for example, by removing attaching screws).
[0043] If desired, each of the main filter panel sections 118, 120
can comprise two smaller filter sections indicated at 118a, 118b,
120a and 120b. In FIG. 2 by splitting the main panel sections in
this manner, the filter panels can be easier to remove and
replace.
[0044] Preferably the inlet attenuator section 28 includes not only
the air inlet 108 (hereinafter sometimes referred to as the first
air inlet), but also a second air inlet opening permitting airflow
into the upper end section of the inlet attenuator housing. A
preferred form of the second air inlet opening 140 can be seen in
FIG. 5. The opening has a square shape and located in the center
thereof is the first air inlet opening 108. In the preferred
embodiment, return air from the floor level of the building where
the unit is installed passes through the second air inlet opening
and into an air mixing chamber 142 that is next to and operatively
connected to the upper air inlet 116 for delivery of an air mixture
thereto. Return air can enter through the opening 140 by passing
through return air outlets in the ceiling of the respective floor
level and then passing either through return air ducts or
preferably through a ceiling plenum located just above the ceiling
106 illustrated in FIG. 1. In the embodiment of FIG. 5, the square
opening 140 is covered with a screen which in a particular
preferred embodiment is one half inch by one half inch bird screen.
The screen helps to prevent any undesired larger objects from
passing through the opening to the filter panels or to the fan
itself. The bird screen is only shown partially in FIG. 5 but it
will be understood that it covers the entire top of the air
handling unit 10 except for the area of the first opening 108.
[0045] An adequate amount of mixing of the fresh incoming air or
secondary air and the return air occurs in the chamber 142 which
includes not only the space above the filter panels 118, 120 but
also the two spaces directly below these panels identified by
references 144 and 146. The central location of the opening 108
also helps the two air flows to mix properly. It will also be noted
that a four sided enclosure 148 extends downwardly from the opening
108 into the air mixing chamber. Mounted in the enclosure 148 is a
variable air damper which can be of standard construction. A
suitable air damper for this purpose is one made by Envirotech. By
means of a standard damper control mechanism, the size of the
opening 108 can be controlled in order to vary the amount of fresh
air or secondary air entering the mixing chamber. The preferred air
damper 150 illustrated in FIG. 5 comprises several, straight
elongate blades that can be rotated about a horizontal axis in
order to open or close the inlet opening 108. These blades can be
parallel blades or opposed blades. Extending upwardly from the
opening 108 can be a rectangular inlet duct section 152 to which a
suitably long air duct (not shown) can be connected for the
delivery of fresh air to the opening 108. The duct section 152 can
be attached to the top of the unit 10 after the unit 10 has been
installed at the required location in the building. It should also
be appreciated that instead of the opening 108 in the top of the
unit 10, it is also possible to deliver the return air to the
mixing chamber 142 by means of a side opening formed in one or more
sides of the inlet attenuator section 28 above the filter panels,
preferably adjacent the top end of the section 28. A side air inlet
may be particularly desirable if the height of the ceiling is
relatively low and there is insufficient room to connect a return
air duct to a top opening.
[0046] Turning now to the preferred form of the upper airflow
passageway 116, as illustrated in FIG. 2, a central bullet or
airflow defining member 154 extends vertically in the passageway.
Although this bullet can be cylindrical and of uniform diameter,
the illustrated bullet has a slight taper in the upwards direction.
The preferred bullet extends from the air outlet 110 upwardly to
the top end of the funnel-shaped passageway 116. The exterior of
the bullet is preferably made of perforated sheet metal and the
inside of the bullet is filled with sound insulating material. The
top end of the bullet is supported in the passageway by means of
the aforementioned support frame 126 to which it can be welded. It
is also, of course, possible to construct the passageway 116
without the bullet 154. With the bullet 154, the bottom air outlet
110 has an annular shape with a round perimeter. The bottom end of
the bullet 154 can be supported by four struts extending radially
from the bottom end to the interior wall 114, these struts being
similar to those illustrated in FIG. 4.
[0047] Preferably, the upper vertical walls (formed by the exterior
panels 82) of the inlet attenuator section 28 are also insulated by
sound absorbing material that extends right up to the top of the
unit. Typically there are two inches of fiberglass insulation in
these walls covered by perforated sheet metal on the interior.
Similarly, the walls or panels surrounding the fan unit 26 can also
be insulated to reduce noise levels.
[0048] Another embodiment of a column like air handling unit 160 is
shown in FIG. 6 of the drawings. This air handling unit is similar
to the air handling unit 10 described above except for the
differences noted hereinafter. Again, it will be understood that
this air handling unit 160 is intended for use in combination with
an elevated floor assembly (not shown). This floor assembly is
mounted on the principal floor 162 of the building. The air
handling unit 160 includes an outlet attenuator 164 which is
mounted on the principal floor 162. Again, a second major section
of the air handling system is mounted on top of the outlet
attenuator and includes the axial fan unit 166 and an inlet
attenuator section 168.
[0049] The outlet attenuator 164 is similar to the corresponding
attenuator in the first described embodiment. However, the
rectangular air outlets, two of which are indicated at 170 and 172
are proportionally larger in this embodiment as compared to the
first embodiment, at least with respect to their height. Also,
extending over each of the outlets is a diffuser or grill 174 that
can be made of metal and that acts to cover the outlet opening. It
will be understood that each diffuser has a large number of
apertures distributed over its surface for the air to pass
through.
[0050] The inlet attenuator 168 has a truncated conical passageway
at 176 through which incoming air can pass downwardly to the axial
fan unit. This attenuator section has two return air inlets located
at 178 and 180 on opposite vertical sides of the unit. Extending
across each of these air inlets is an air filter 182 which, in one
preferred embodiment, has a thickness of one inch. Arranged
immediately adjacent each of these air filters is a heat exchanging
coil unit 184, 186. Each of these coil units is mounted in the
inlet attenuator section so that the incoming air flow passes
through the coil unit. It will be appreciated that the coil unit
can be set up for either heating the incoming air or cooling this
air or a combination of two coil units can be mounted at each inlet
to provide either heating or cooling, as desired. The heat
exchanger coil unit can be of standard construction per se, for
example with copper or aluminum tubes winding back and forth across
the unit so that the air will be forced to pass between the tubes
which may also be provided with metal fins. It is quite possible to
have only one return air inlet opening fitted with a heat
exchanging coil unit if only one return air inlet is required.
Where there is more than one air inlet, the incoming air flows will
mix in the air mixing chamber 190 formed between the two heat
exchanging coil units. Fresh or make-up air at room temperature can
be provided to this mixing chamber through a third inlet opening
located in the top 200 of the inlet attenuator. After this mixing
has occurred, the incoming air will then be forced downwardly
through the passageway 176, being drawn into this passageway by the
fan unit.
[0051] Again, it will be understood that the upper portion of the
inlet attenuator is preferably located above a false ceiling
indicated at 192
[0052] In one preferred embodiment of this particular column air
handling unit, the heat exchanging coil units are cooling coils
with each unit having a horizontal length of forty inches and a
vertical height of twenty inches and having a cooling capacity of
450 FPM. Preferably at least one side of the upper section of the
inlet attenuator is covered with a removable panel (not shown).
This panel can be removed by maintenance or service personnel in
order to gain access to the air mixing chamber. This panel is
located on one of the vertical sides that is perpendicular to the
two sides on which the heat exchanging coil units are provided.
[0053] A preferred form of the air inlet and sound attenuator
section of this invention is illustrated in FIG. 7, this particular
section being indicated generally at 202. It will be understood
that this inlet section is constructed in a manner generally
similar to the inlet section of FIG. 6 except as described
differently hereinafter. As in the earlier embodiments, this inlet
section includes an inlet housing 204 and an annular bottom air
outlet 206 with a round periphery. Extending downwardly to this air
outlet is an upper airflow passageway 208 which is divided into
smaller airflow passageways as explained hereinafter. The
passageway 208 tapers inwardly in a downwards direction. As in the
embodiment of FIGS. 1 and 2, the air inlet and sound attenuator 202
is provided with an upper air inlet located at 210 which can be
similar to that provided by the rectangular air inlet duct section
152 in the first embodiment. The air inlet section 202 of FIGS. 7
and 8 also has one or more and preferably at least two side air
inlets indicated at 212 and 214. There can be as many as four side
air inlets, one on each of the vertical sides of the air inlet
section 202. At least one of these air inlets 210, 212, 214 is
adapted to receive fresh incoming air which can be ducted to the
unit through the ceiling area and at least one of the air inlet
openings at 210, 212, and 214 is adapted to receive return air from
the building. During use of this particular air handling system,
the fresh incoming air and the return air are mixed in the air
inlet and sound attenuator section 202 and therefore a mixed
airflow is delivered by the upper airflow passage 208 to the inlet
of the fan unit.
[0054] The air inlet section 202 contains standard sound absorbing
material which is positioned behind perforated interior walls 218
made of sheet metal. These interior walls form vertically extending
sides of the upper airflow passageway 208. Thus this passageway is
surrounded with sound absorbing material.
[0055] The inlet section 202 includes a central, elongate airflow
member 220 which is mounted centrally in the upper airflow
passageway 208 and which has a vertical longitudinal axis. This
airflow member 220 is preferably filled with sound absorbing
material 222. The airflow member 220 has an outer peripheral wall
224 which is made of perforated sheet metal and that diverges
outwardly from an upper end at 226 to a bottom end thereof. Unlike
the central airflow members of the above described embodiments, the
airflow member 220 preferably extends up to a point near or at the
top of the air inlet section 202. An upper end section 227 of the
airflow member preferably is sloped at a greater acute angle to the
vertical central axis of the member. This feature together with
other features included in the air inlet section 202 provide the
unit with improved air attenuating qualities, reducing the sound
from the fan that comes out of the air inlet section to a low
level.
[0056] The preferred air inlet section 202 further includes two or
more intermediate airflow members 230 to 233, two of which can be
seen in FIG. 7. These airflow members are mounted in the upper
airflow passageway 208 and they are spaced from the central
elongate airflow member 220 as well as from the internal walls 218.
As illustrated in FIG. 7, each of these airflow members is tapered
inwardly in a downwards direction from an upper end section
thereof, tapering to a point at the air outlet 206. The number of
airflow members 230 to 233 will depend, at least in part on the
number of the air inlets 212, 214. In the situation where there are
two air inlets located on opposite sides of the unit, there are at
least two of the intermediate airflow members 230, 232 but
optionally there can also be two interconnecting, similar airflow
members 231, 233. In the case of four side air inlets, one on each
of the vertical sides of the air handling unit, there are normally
four of the airflow members 230 to 233. The illustrated preferred
airflow members are constructed on their periphery with an arcuate
top sheet metal panel 236, an inner panel section 238 that extends
down to the bottom point, an outer arcuate panel 240, and a
transition wall section 242 that extends downwardly from the panel
section 240. It will be understood that the inner panel section 238
is a transition panel providing a transition in cross-section of
the inner airflow passageway 244 from rectangular (about its outer
periphery) at the top to circular at the bottom. Similarly the
transition wall panel section 242 changes the outer airflow
passageway 246 from rectangular at its upper end to circular at its
bottom.
[0057] It will be understood that the airflow members 230 to 233
can be rigidly connected to one another, for example by welding,
and can be connected to the interior walls 218 by suitable, rigid
connecting straps (not shown) that do not interfere with the
airflow significantly. Also each of the airflow members 230 to 233
is substantially filled with sound absorbing material indicated at
250. This material can, for example comprise fibreglass insulation.
It will be seen that the effect of the airflow members 230 to 233
is to divide up the return airflow entering through the side air
inlets and this helps to ensure that the return air entering into
the unit flows smoothly and without undue turbulence into the fan
inlet. Furthermore the presence of these airflow members helps to
block direct transmission of sound from the fan unit through the
air inlet section 202 and out through the air inlets 212, 214.
[0058] In a preferred embodiment of this unit, there is at least
one heat exchanging coil unit arranged in at least one of the air
inlets 212, 214 so that incoming air passes through the coil unit.
In FIGS. 7 and 8 each of the air inlets 212, 214 is provided with a
heat exchanging coil unit 255. These heat exchanging coil units can
be of standard construction. For example they may comprise one or
more lengths of pipe 256 which wind back and forth across the inlet
and through which a suitable heat exchanging fluid, such as water,
passes. A number of metal fins can be mounted on these pipes and
arranged in a closely spaced manner and parallel to one another as
indicated in FIG. 7. If desired, there can be one set of heat
exchanging coils for heating purposes and a separate, adjacent set
of heat exchanging coils for cooling purposes. Alternatively, only
one set for cooling or one set for heating may be provided.
Preferably there are mounted on the outside of these heat
exchanging coils air filter panels indicated at 260 in FIG. 8.
These air filter panels can be supported directly by the metal
frame members extending about their periphery including horizontal
frame members 264 and 266 and the vertical frame members at 75.
[0059] A preferred optional feature of this air inlet section is an
acoustical resonator 265 mounted at a bottom end of the elongate
airflow member 220 and located adjacent the fan unit. The
illustrated air inlet section in fact has two of these resonators
including a second resonator 266 located directly below the
resonator 265. Each resonator can be filled with a light, sound
absorbing fibre, if desired, and each has a series of circular
holes 268 distributed about its periphery. The number of holes will
vary depending upon the sound range that the attenuator is intended
to reduce.
[0060] The use of acoustical resonators of this type has been
previously illustrated and described in U.S. Pat. No. 5,426,268
issued Jun. 20, 1995, the disclosure and drawings of which are
incorporated herein by reference. An acoustical resonator of this
type is useful in reducing the blade passage frequency noise. The
resonator is in the form of an enclosed chamber having the
aforementioned holes 268 about its periphery. The chamber is
defined by a generally cylindrical side wall 270 and circular end
walls at the top and bottom edges of the side wall. The upper
airflow passageway 208 extends about the cylindrical side wall 270
of each resonator. The walls of the chamber can, for example be
made of sixteen gauge sheet metal. It is also possible for the
acoustical chamber to be empty rather than filled with light
fibre.
[0061] Turning now to a further embodiment of the air inlet and
sound attenuator section that can be used in the invention, this
further embodiment is illustrated in FIGS. 10 and 11 of the
drawings. This further air inlet and sound attenuator section is
indicated generally at 270 and again this embodiment is similar to
the previously described air inlet and sound attenuator sections
except for the differences herein described. This air inlet section
270 again has an inlet housing 272 with a round bottom air outlet
274 that is also annular. The upper airflow passageway that extends
between the air inlets and the annular air outlet 274 is indicated
generally by 276 and it will be seen that this passageway is
divided into an outer airflow passageway 278 and an annular inner
airflow passageway 280. The upper airflow passageway 276 is
surrounded on vertically extending sides thereof with sound
absorbing material 282 which is of course covered on the outside by
exterior panels of the housing 272. The upper section of the
housing 272 had an air inlet opening in two or more of the
vertically extending sides with two of these openings 284, 286
visible in FIG. 10. There can be as many as four of these air inlet
openings, one on each of the four vertical sides of the air inlet
section, if desired. As in the embodiment of FIG. 7, there can be a
heat exchanging coil unit 255 located in one or more of these air
inlet openings in order to heat or cool the incoming airflow.
[0062] It will be seen that the two smaller airflow passageways 278
and 280 each extend from the air inlet openings to the bottom air
outlet 274 and these passageways are separated by a substantially
conical divider wall 290 which is substantially coaxial with the
upper airflow passageway 276. Although it is possible for this
divider wall 290 to be constructed of non-perforated sheet metal
and for the wall to be only the thickness of the single sheet metal
panel, in a preferred version of this air inlet section the divider
wall 290 is made with two, spaced-apart sheet metal walls 292, 294
with each of these sheet metal walls having a substantially conical
shape. A relatively narrow space between these perforated metal
walls is filled with standard sound absorbing material 296. It is
also possible that only one of the two sheet metal walls is
perforated while some or all of the other sheet metal wall is
non-perforated with the exact configuration depending on various
factors such as the amount of sound reduction required, airflow
speed, etc. In one possible embodiment, only the outer metal wall
294 is perforated, this wall forming an outer airflow defining
surface which faces substantially downwardly and radially
outwardly.
[0063] In the embodiment of FIGS. 10 and 11, the upper airflow
passageway 276 is defined by an upper interior wall 300 and a lower
interior wall 302 and both of these walls are made of perforated
sheet metal. The lower interior wall 302 covers the aforementioned
sound absorbing material 282. As can be seen from both FIGS. 10 and
11, both of these interior walls have a substantially conical shape
although each wall has a rectangular top edge that can be seen
clearly in FIG. 11. This conical configuration provides for a very
smooth incoming airflow that extends from the air inlets 284, 286
to the annular outlet at 274. The conical interior space located
within the interior wall 300 is filled with sound absorbing
material 304, this material not being shown in FIG. 11 for purposes
of illustration. It will be understood that a top wall or panel
closes the top of the air inlet section 270 and thus there is no
air inlet in the top of this version.
[0064] Although only two heat exchanging coil units 255 can be seen
in FIG. 10, if in fact this air inlet section 270 has air inlets in
all four sides, it will be appreciated that there can be a heat
exchanging coil unit mounted in the air inlet of each side so that
all of the airflow entering the unit is required to pass through
the heat exchanging coil units. If there is no air inlet on one
side of a particular air inlet section 270, the boxlike space where
there would be a heat exchanging coil unit if the side had an air
inlet is preferably filled with sound absorbing material that is
covered on the inside surface with perforated sheet metal.
[0065] It will also be appreciated by those skilled in the air
handling art that the air inlet silencer of FIGS. 10 and 11 can
also be used as an outlet silencer in the column fan unit of this
invention. In this situation, the air inlet and sound attenuator
section 270 would be positioned downstream from the axial fan unit
and its annular air outlet at 274 would become an inlet to receive
the airflow from the air fan. The outlets for this air outlet
attenuator would then be the air outlets at 284, 286. In other
words, the attenuator section 270 when used as an air outlet
section can be used in place of the air outlet attenuator 24
illustrated, for example, in FIG. 2. It might also be noted that
the optional acoustic resonator 265 can also be employed when the
silencer unit of FIG. 10 is used as an air outlet silencer.
[0066] From the above description, it will be seen that an
efficient air handling system has been provided for use
particularly in high-rise buildings. The use of the air handling
system of the invention can avoid the need for a large mechanical
room to hold a relatively large air handling system capable of
supplying air to an entire high-rise building. The system of the
invention in its preferred form has several additional advantages
including the fact that its column like appearance can make it
easier to conceal on each floor of the building as it can have the
appearance of a structural column of the building. The present
system also can provide maximum flexibility with respect to the
distribution of the air supply on each floor level of the building
and it reduces substantially the need for the ducting of
conditioned air to various locations in the building. The use of
such a system will also permit the owner of the building to add
heating or cooling capability almost at any desired location in the
building without affecting other regions of the building and
without having to make major modifications to the complete air
handling system. In this regard, it should be noted that heating or
cooling coils can be mounted in the air mixing chamber to give the
unit 10 either a heating or cooling capability (or both). Preferred
versions of this air handling system can also be made relatively
quiet so as not to disturb persons located in the vicinity of the
air handling unit.
[0067] It will be readily apparent to those skilled in the air
handling art that various modifications and changes can be made to
the described air handling system without departing from the spirit
and scope of this invention. Accordingly, all such modifications
and changes as fall within the scope of the appended claims are
intended to be part of the present invention.
* * * * *