U.S. patent application number 17/353800 was filed with the patent office on 2021-10-07 for conditioned air blower system for loading dock trailer.
This patent application is currently assigned to DL Manufacturing, Inc. The applicant listed for this patent is DL Manufacturing, Inc.. Invention is credited to Kyle J. Berean, Joseph Markert, Donald L. Metz.
Application Number | 20210310670 17/353800 |
Document ID | / |
Family ID | 1000005669458 |
Filed Date | 2021-10-07 |
United States Patent
Application |
20210310670 |
Kind Code |
A1 |
Markert; Joseph ; et
al. |
October 7, 2021 |
CONDITIONED AIR BLOWER SYSTEM FOR LOADING DOCK TRAILER
Abstract
A facility-based conditioned air blower system for ventilating a
trailer interior includes a fan and a split air conditioner system.
The fan includes an inlet portion, a fan housing, and a discharge
portion. The discharge portion includes a pivoting elbow conduit
configured to rotate into and away from the trailer interior. The
split air conditioner system includes an evaporator unit coupled to
the inlet portion of the fan, and further coupled to a condenser
unit by way of a closed-loop refrigerant line.
Inventors: |
Markert; Joseph; (East
Syracuse, NY) ; Metz; Donald L.; (Kirkville, NY)
; Berean; Kyle J.; (Chittenango, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DL Manufacturing, Inc. |
North Syracuse |
NY |
US |
|
|
Assignee: |
DL Manufacturing, Inc
|
Family ID: |
1000005669458 |
Appl. No.: |
17/353800 |
Filed: |
June 21, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15169467 |
May 31, 2016 |
11041641 |
|
|
17353800 |
|
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|
|
62167700 |
May 28, 2015 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60H 1/00471 20130101;
B60H 1/00014 20130101; F24F 1/0022 20130101; F24F 1/0011 20130101;
F24F 11/76 20180101 |
International
Class: |
F24F 1/0011 20060101
F24F001/0011; F24F 1/0022 20060101 F24F001/0022; B60H 1/00 20060101
B60H001/00; F24F 11/76 20060101 F24F011/76 |
Claims
1. A facility-based conditioned air blower system for ventilating a
trailer interior at a loading dock, comprising: a fan comprising an
inlet portion, a fan housing, and a discharge portion, the
discharge portion comprising a pivoting elbow conduit configured to
rotate into and away from the trailer interior; and a split air
conditioner system comprising an evaporator unit coupled to a
condenser unit by way of a closed-loop refrigerant line, the
evaporator unit coupled to the inlet portion of the fan.
2. The facility-based conditioned air blower system according to
claim 1, wherein the fan comprises a centrifugal blower.
3. The facility-based conditioned air blower system according to
claim 2, wherein the centrifugal blower comprises first and second
inlet portions, the first inlet portion comprising a first opening
on a side of the fan housing, the second inlet portion comprising a
second opening on an opposing side of the fan housing, the
discharge portion comprising an opening on the fan housing
transverse from the first and second inlet openings.
4. The facility-based conditioned air blower system according to
claim 1, further comprising a controller operable to interlock
operation of the fan in response to an operational state of another
system at the loading dock.
5. The facility-based conditioned air blower system according to
claim 4, wherein the controller enables operation of the fan in
response to an indication that an overhead door is open at the
trailer interior.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/169,467, filed May 31, 2016, entitled
"CONDITIONED AIR BLOWER SYSTEM FOR LOADING DOCK TRAILER," which
claims the benefit of U.S. Provisional Application Ser. No.
62/167,700, filed May 28, 2015, entitled "LAMINAR FLOW AIR MOVER
SYSTEM HAVING TEMPERATURE-CONDITIONED INLET AIR", which
applications are incorporated herein in their entirety by
reference.
BACKGROUND OF THE INVENTION
[0002] This disclosure relates generally to a conditioned air
blower and, more specifically, to a fan having
temperature-conditioned air provided at the fan inlet. A noted
problem within the loading dock industry concerns ventilation
inside a trailer when workers load and unload the contents of the
trailer. Standard loading dock fans provide high volume airflow,
but since the airflow is at a low velocity, and randomly directed,
the airflow does not travel much more than half the trailer length
before it recirculates back into the fan's intake. As a result, the
air in the back of the trailer (e.g., towards the cab) becomes
stagnant and hot. One recent improvement to the standard loading
dock fan is a laminar flow centrifugal blower having a necked-down
discharge tube with an elbow that allows the discharge air to be
directed into the trailer. The combination of laminar flow and the
gradual decrease in diameter of the discharge tube provides a high
velocity discharge stream that is able to efficiently ventilate the
entire interior of the trailer.
[0003] Although a laminar flow centrifugal blower can be useful and
may be advantageous for certain applications, it does suffer from
drawbacks. One drawback is that the high velocity discharge air
stream is the same ambient temperature as the loading dock bay
area, which may be much warmer or cooler than the rest of the
facility. In some loading dock bay areas, the overhead doors are
left in the open position to accommodate frequent trailer traffic
at the docks. In such cases, a flexible PVC strip curtain may be
installed to separate the loading bay area from the remainder of
the shop floor. In time, then, the temperature of the loading bay
area approaches the outdoor temperature. In other loading dock
applications, the doors may be closed more frequently but the bay
area may have insufficient HVAC service to keep the temperature and
humidity of the bay area at a comfortable level. Thus, if the
loading dock bay area is uncomfortably warm, or uncomfortably cold,
the ventilation air in the trailer will be the same uncomfortable
temperature.
BRIEF SUMMARY OF THE INVENTION
[0004] In one aspect of the invention, a facility-based conditioned
air blower system for ventilating a trailer interior includes a fan
comprising an inlet portion, a fan housing, and a discharge
portion. The discharge portion includes a pivoting elbow conduit
configured to rotate into and away from the trailer interior. The
facility-based conditioned air blower system further includes a
split air conditioner system comprising an evaporator unit coupled
to a condenser unit by way of a closed-loop refrigerant line. The
evaporator unit is coupled to the inlet portion of the fan.
[0005] In one embodiment, the fan comprises a centrifugal
blower.
[0006] In one example, the centrifugal blower includes first and
second inlet portions. The first inlet portion includes a first
opening on a side of the fan housing, the second inlet portion
includes a second opening on an opposing side of the fan housing,
and the discharge portion includes an opening on the fan housing
transverse from the first and second inlet openings.
[0007] In another aspect of the invention, the facility-based
conditioned air blower system includes a controller operable to
interlock operation of the fan in response to an operational state
of another system at the loading dock.
[0008] In one example, the controller enables operation of the fan
in response to an indication that an overhead door is open at the
trailer interior.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0009] The features described herein can be better understood with
reference to the drawings described below. The drawings are not
necessarily to scale, emphasis instead generally being placed upon
illustrating the principles of the invention. In the drawings, like
numerals are used to indicate like parts throughout the various
views. For example, differing embodiments of like elements may be
assigned 100-series, 200-series, and so on.
[0010] FIG. 1 depicts a block schematic diagram of a conditioned
air blower system in accordance with another embodiment of the
invention;
[0011] FIG. 2 depicts a perspective view of a conditioned air
blower system in accordance with one embodiment of the
invention;
[0012] FIG. 3 depicts an exploded perspective view of a centrifugal
blower shown in FIG. 1;
[0013] FIG. 4 depicts a plan view of a conditioned air blower
system with a block schematic diagram in accordance with one
embodiment of the invention;
[0014] FIG. 5 depicts a perspective view of an adapter cuff in
accordance with one embodiment of the invention; and
[0015] FIG. 6 depicts a plan view of the conditioned air blower
system shown in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
[0016] As used herein, the term "trailer" means a vehicle with an
enclosed cargo area, and may include, but is not limited to,
tractor trailer trucks, refrigerated trucks, box trucks, delivery
trucks, and vans.
[0017] FIG. 1 illustrates a schematic diagram of an exemplary
embodiment of a conditioned air blower system 10 that may be used
to provide a more comfortable flow of air to a trailer interior.
The conditioned air blower system 10 includes a centrifugal blower
12 having at least one inlet portion 14 to direct air into the
blower, and a discharge portion 16 to direct air from the blower 12
into the trailer interior. The conditioned air blower system 10
further includes a heat exchange unit 18 to supply
temperature-conditioned air 20 to the inlet portion 14 of the
centrifugal blower 12. The term `temperature-conditioned air` means
air that has been heated or cooled relative to the temperature of
the ambient air 22 in the loading dock area, including air that has
had its moisture content adjusted relative to that surrounding the
loading dock area. The heat exchange unit 18 includes heat exchange
elements 24 to condition a supply of ambient air 22 by raising or
lowering the temperature of the air. In some embodiments, the
conditioned air blower system 10 includes a supply duct 26
connecting the output of the heat exchange unit 18 with the inlet
portion 14 of the blower 12.
[0018] The conditioned air blower system 10 may further include a
controller 28 operatively associated with the centrifugal blower 12
and the heat exchange unit 18. The controller can be configured to
monitor an input condition or sensor related to the centrifugal
blower 12 and, in response to the condition, regulate the supply of
temperature-conditioned air 20 to the blower 12.
[0019] FIG. 2 illustrates a portion of a conditioned air blower
system 10 in accordance with one embodiment of the invention. The
centrifugal blower 12 includes two inlet portions which, as defined
herein, generally refers to the hardware required to direct air
into the blower 12. The particular configuration of centrifugal
blower 12 depicted in FIG. 2 draws air in from both sides of the
blower 12. Thus, the centrifugal blower 12 includes a first inlet
portion 14a that draws in ambient air from the loading dock bay
area, and a second inlet portion 14b that interfaces with a supply
duct 26 from a heat exchange unit 18 (not shown). As shown, the
centrifugal blower 12 may be mounted a distance away from the
loading dock inside wall 30 to provide sufficient clearance for the
supply duct 26 to be mounted behind the blower.
[0020] As noted, the centrifugal blower 12 may have two inlet
portions 14a, 14b on opposing sides of the blower housing. In the
illustrated embodiment, the supply duct 26 with
temperature-conditioned air 20 is mounted to inlet portion 14b. In
some environments it may be desirable to partially block or
completely block the opposing inlet portion (e.g., 14a) to maximize
the temperature-conditioned air 20 entering the trailer. In some
embodiments, then, a damper system 32 may be utilized to regulate
the amount or degree or percentage of ambient air supplied to the
centrifugal blower 12. The damper system 32 (not illustrated) may
be positioned within the inlet portion 14a of the centrifugal
blower 12. In one example, the damper system 32 may be a circular
plate that can be manually rotated to block all or a portion of the
ambient air entering inlet portion 14a.
[0021] The blower 12 may further include a discharge portion 16
configured to direct air from the blower into the trailer interior
42. The blower 12 may be mounted above and/or to the side of the
overhead door frame to minimize obstruction with the trailer
interior 42 and decrease the likelihood of being hit by a forklift.
The discharge portion 16 may include a straight discharge adapter
34 configured to transition the discharge from a rectangular cross
section to a smaller circular cross section, and may further
include an elbow conduit 36 to turn the air flow and direct it into
the trailer interior 42. The exit of the elbow conduit 36 may be a
smaller diameter than the entrance to further backpressure the
centrifugal blower 12 for better performance. The discharge portion
16 and/or the elbow conduit 36 may further include a break-away
pivoting portion 38 that permits the elbow to rotate about its
central axis (indicated by arrows R-R), enabling a range of airflow
adjustment into the trailer and also enabling the elbow conduit 36
to pivot completely out of the overhead door opening when not in
use. The break-away pivoting portion 38 may also include a
break-away feature that allows the elbow conduit 36 to snap free
from the discharge adapter 34 in the event a forklift hits the
elbow. The break-away feature may also permit easy
re-installation.
[0022] In operation, the controller 28 may be operatively
associated with the centrifugal blower 12 and the heat exchange
unit 18 (FIG. 1). The controller may be configured to monitor a
condition related to the centrifugal blower 12 and regulate the
supply of temperature-conditioned air 20 in response to the
condition. The controller 28 may also operate the damper system 32
(e.g., activate and position the damper). In one example, the
controller 28 could monitor an environmental condition such as the
temperature inside the trailer. A wireless temperature sensor 40
may be placed in the trailer interior 42 at the front trailer wall.
The output data of the temperature sensor 40 may be evaluated by a
processor within the controller 28. In one example, the temperature
data may be compared to a threshold limit value stored in a lookup
table. Based upon the reading, the controller 28 may execute
instructions, such as powering on the blower 12 and the heat
exchange unit 18 if the temperature reading is greater than the
threshold value (e.g., 80.degree. F.). In a similar manner, the
controller 28 may power off the blower 12 and heat exchange unit 18
if the temperature reading subsequently drops below the threshold
value.
[0023] In another example, the temperature sensor 40 may be located
in the discharge portion 16 of the centrifugal blower 12. The
controller 28 may be configured to regulate a parameter associated
with the centrifugal blower 12, such as air discharge temperature
or air flow. For example, the air discharge temperature data may be
compared to a desired range of values stored in a lookup table.
Based upon the temperature data, the controller 28 may execute
instructions to power on the heat exchange unit 18 and increase or
decrease the speed of the blower 12 to maintain the air discharge
temperature within the desired range.
[0024] In another embodiment of the invention, the controller may
be configured to monitor a simple on-off switch. The conditioned
air blower system 10 may be controlled by a switch that is in a
`normally off` position. In the event a user desires
temperature-conditioned air 20 into the trailer, the user may
manually select the `on` position of the switch. In response, the
controller 28 may turn on power to the centrifugal blower 12.
[0025] In another example of its operation, the centrifugal blower
12 may be activated without use of a controller. For example, the
centrifugal blower 12 may be manually powered on using a simple
on-off switch, or by plugging its power cord to a standard 120
volts a/c (VAC) outlet. The damper system 32, if present, may also
be manually operated without a controller.
[0026] In another embodiment of the invention, the controller 28
may be configured to monitor an operating condition of the
centrifugal blower 12. In one example, the controller 28 may
monitor a current sensor coupled to a power cord on the motor of
the centrifugal blower 12. The current sensor may give an
indication of the power level at which the centrifugal blower 12 is
operating. The controller 28 may command more or less power to the
centrifugal blower 12 in response to, for example, a temperature
sensor positioned in or near the discharge portion 16 of the
blower, or within the trailer interior 42. In another example, the
controller 28 may monitor a shaft speed sensor coupled to the motor
of the blower.
[0027] The output data from the temperature sensor 40 may also be
utilized as input for a feedback control loop to position the
damper plate 32. For example, the damper could be closed down to
minimize airflow through inlet portion 14a of the centrifugal
blower 12, thereby maximizing the cooling capability of the
conditioned air blower system 10. A low amperage servo motor could
operate the damper system 32 in response to commands from the
controller 28.
[0028] The centrifugal blower 12, shown in greater detail in FIG.
3, may include an internal motor 44 secured within a blower housing
46. The motor 44 may be powered by a 120 VAC supply, provided
through a power cord 48. The driveshaft of the motor 44 turns a
blower fan 50, known within the industry as a squirrel cage. In
operation, air is drawn in from the sides of the blower housing 46,
or inlet portions 14a, 14b, is then turned 90 degrees, accelerates
due to the centrifugal force as it flows over the fan blades 50,
and then exits the blower housing 46. The discharge air is further
accelerated as it passes through the necked-down discharge adapter
34, then accelerated further as it passes through the necked-down
elbow conduit 36. Upon discharge, the air has sufficient velocity
to flow down the length of the trailer, bounce off the front
trailer wall, and circulate back through the middle and opposite
side of the trailer, thereby creating a ventilated environment.
[0029] The centrifugal blower 12 may further include a mounting
assembly to properly position the blower over the door frame of the
loading dock. In one embodiment, the mounting assembly includes a
bracket plate 52 fastened to an air inlet ring 54, which is in turn
fastened to the blower housing 46. The bracket plate 52 includes a
protrusion 56 or `ear` along its periphery. The protrusion 56
defines an aperture 58 configured to accommodate a mounting bar 60
in sliding engagement. A first end of the mounting bar 60 includes
a blower housing mounting plate 62 which is secured to the
centrifugal blower housing 46 adjacent the outlet opening thereof
by means of screws or rivets 64 (FIG. 2). The opposite end of the
mounting bar 60 telescopically engages a larger-diameter mounting
tube 66. The end of the mounting tube 66 opposite the telescoping
engagement includes a mounting plate 68, which may be secured to
the wall 30 of the loading dock, adjacent an overhead door, by any
suitable means such as screws (FIG. 2). As can be appreciated with
reference to FIG. 2, the mounting hardware allows the blower 12 to
extend towards and away from the wall 30, which may be beneficial
in accommodating the connection to the supply duct 26, or an
externally mounted motor.
[0030] In another embodiment of the invention, the centrifugal
blower 12 may have only one inlet portion 14. For example,
referring to FIG. 2, the inlet portion 14b may be replaced by an
externally mounted motor, such that no air enters from that side of
the blower 12. Or, in another example, there is no inlet on that
side of the blower 12. In such an arrangement, the sole inlet
portion 14 would receive the temperature-conditioned air 20 from
the heat exchange unit 18. In one example, the supply duct 26 could
be configured to separate from the inlet portion 14 by latches or
the like when the temperature-conditioned air 20 is not needed.
[0031] The heat exchange unit 18 may be selected from any suitable
configuration that fits the space, availability, and requirements.
For example, the heat exchange unit 18 may be part of a non-ducted
air conditioning system, such as the evaporative heat exchanger in
a residential split or mini-split system. Split and mini-split
systems have an outdoor compressor/condenser, and an indoor
evaporator or air-handling unit. A conduit, which houses the power
cable, refrigerant tubing 24, suction tubing, and a condensate
drain, links the outdoor and indoor units. The
temperature-conditioned air 20 output from the air handling unit
may be routed to the inlet portion 14 of the centrifugal blower
12.
[0032] In another example, the heat exchange unit 18 may be part of
a ducted HVAC system, such as direct expansion (DX) or chilled
water system in a central plant. A ducted system may also include a
packaged system, such as floor standing air cooled or water cooled
air conditioner, or an air cooled ductable split system. In the
ducted systems, a portion of the temperature-conditioned air 20
from the air handling unit can be routed to the inlet portion 14 of
the centrifugal blower 12.
[0033] Turning now to FIG. 4, wherein like numerals are used to
indicate like parts from FIGS. 1-3, shown is another embodiment of
a conditioned air blower system 110 along with a schematic diagram
of a heat exchange unit 118 that provides temperature-conditioned
air 120 to multiple blowers 112. The conditioned air blower system
110 is illustrated as seen from inside a loading dock bay area,
looking out through the overhead doors 170. Doors 170a and 170d are
closed, and doors 170b and 170c are open. Truck trailers may be
backed up to the open doors 170b and 170c, such that trailer
interiors 142b, 142c are shown ready for load or unloading
operations. As can be seen with reference to FIG. 4, the
centrifugal blowers 112 are mounted above and off to the side of
the overhead doors 170, so only a small portion of the blower
discharge 116 occupies the door opening.
[0034] In the illustrated embodiment, the heat exchange elements
124 of the heat exchange unit 118 are contained in an air handling
unit 172 of a building's heating/ventilation/air conditioning
(HVAC) system. As noted above, the air handling unit 172 supplies
temperature-conditioned air 120 to the inlet portion of the blower
housing via the supply duct 126. The air handling unit 172 may
include a secondary blower 174 to move the temperature-conditioned
air 120 through the ductwork 126.
[0035] The air handling unit 172 may also include components to
heat the temperature-conditioned air 120 in cold weather, such as a
humidifier 176 coupled to the heat exchange unit 118 to increase
the moisture content of the temperature-conditioned air 120,
heaters, or a hot water coil.
[0036] As noted above, a controller 128 is operatively associated
with the centrifugal blower 112 and the heat exchange unit 118. The
controller 128 is configured to monitor a condition related to the
centrifugal blower 112 and regulate the supply of
temperature-conditioned air 120 in response to the condition. In
one embodiment, the controller 128 regulates the supply of
temperature-conditioned air 120 by executing instructions to
operate the secondary blower 174 in the air handling unit 172. The
controller 128 may interface with or may comprise a controller
operating a building's automation and control network, such as the
BACnet communications protocol.
[0037] In another embodiment of the invention, the conditioned air
blower system 110 may include a damper system 132 configured to
regulate the amount or degree or percentage of
temperature-conditioned air 120 supplied to the centrifugal blower
112. The damper system 132 may be positioned within the inlet
portion 114 of the centrifugal blower 112, or may be accommodated
within the air handling unit 172. The damper system 132 may be
activated and positioned by the controller 128. In one example, the
controller 128 could monitor a condition such as a temperature
sensor placed in the trailer interior 142. Based upon demand, the
controller 128 could execute instructions, such as a control loop,
to maintain a balance point with the HVAC system. A low amperage
servo motor could operate the damper system 132 in response to
commands from the controller 128.
[0038] In another embodiment of the invention, the conditioned air
blower system 110 may be operatively associated with a dock safety
sensor system, such as the Smart Chock.TM. brand sensor system sold
by DL Manufacturing, Syracuse, N.Y. Briefly, the dock safety sensor
system is a trailer restraint system that secures the trailer while
communicating with drivers and loading dock workers to ensure a
safe and productive work environment. The dock safety sensor system
includes a chock (not shown), an outside-mounted light box 178
(shown in dashed lines because it is located on the other side of
the dock wall 130), and an inside-mounted control panel 180 with
light box.
[0039] In operation, in a first step, as a driver backs up to a
closed overhead door 170, the outside light box 178 illuminates
green, indicating it is safe to proceed. Concurrently, the control
panel 180 illuminates a red light, indicating the trailer is not
chocked and it is unsafe to open the overhead door 170. In a second
step, when the trailer is parked and chocked, a sensor in the chock
relays the condition to the inside control panel 180, which
illuminates a chock indicator light on the outside light box 178.
Concurrently, the red light turns off and a green light illuminates
on the inside control panel 180, indicating the trailer is chocked
and it is safe to open the overhead door 170. In a third step, a
photovoltaic sensor detects when the door is opened, relays the
condition to the inside control panel 180, and a flashing red light
is illuminated on the outside light box 178, indicating to the
truck driver that loading operations are in progress and it is
unsafe to remove the chock. The green light remains illuminated on
the inside control panel 180. In a fourth step, when loading or
unloading operations are complete and the overhead door 170 is
closed, the flashing red light is turned off on the outside light
box 178, indicating it is now safe to remove the chock. In a fifth
step, after the driver removes the chock, the sensor in the chock
relays the condition to the inside control panel 180, which turns
off the chock indicator light on the outside light box 178.
Concurrently, the green light turns off and the red light
illuminates on the inside control panel 180, indicating the trailer
is no longer chocked and it may be unsafe to open the overhead door
170.
[0040] In one embodiment of the invention, the inside control panel
180 can interlock and control operation of the centrifugal blower
112. For example, at step three above, when the sensor detects the
overhead door 170 is open and the condition is relayed to the
inside control panel 180, the controller 128 may send instructions
to initiate operation of the centrifugal blower 112. The
instructions may take the form of a simple on/off command, or in
other examples, may initiate a logic sequence stored in the memory
of the controller 128 to determine if blower operation is
warranted. In another example, the instructions may control
operation of the secondary blower 174 in the air handling unit 172,
or the damper system 132.
[0041] Turning now to FIG. 5, in another embodiment of the
invention, an inlet portion of a conditioned air blower system may
include an adapter cuff 282 to better distribute the air flow over
the inlet, or to provide a functional inlet flow distribution in
limited space. The adapter cuff 282 includes a first end 284 to
mate with a supply duct from an air handling unit, such as supply
duct 126 and air handling unit 172 shown in FIG. 4, and a cuff
region 286 to modify the inlet flow geometry. In the illustrated
embodiment, the cuff region 286 includes symmetric cuff components
286a and 286b. Typical centrifugal blowers have uneven flow
distribution over the inlet face, or from one side to the other,
and the adapter cuff 282 can be used to redistribute the internal
flow to provide more uniform entry into the blower. The adapter
cuff 282 can also provide a low-profile entry path into the
centrifugal blower 212. In one embodiment, the profile may be
approximately one-half the width of the supply duct. In other
examples, the profile may be between one-third and three-fourths
the width of the supply duct.
[0042] FIG. 6 depicts a plan view of a conditioned air blower
system 310 according to yet another embodiment of the invention. In
this embodiment, the components utilized to supply
temperature-conditioned air to the centrifugal blower 312 are
stand-alone units that do not tie into the building's existing HVAC
system. As a result, installation of the conditioned air blower
system 310 is less complicated, less labor intensive, and reduces
capital cost.
[0043] The conditioned air blower system 310 may include many of
the components as depicted in FIG. 2, such as the centrifugal
blower 312, including the discharge adapter 334 and elbow conduit
336. The conditioned air blower system 310 further includes a heat
exchange unit, embodied as an evaporator unit 387, such as that
found in a residential split air conditioning unit. The evaporator
unit 387 includes an ambient air inlet portion 388, an evaporator
coil 389 as part of a closed-loop refrigerant line 390, and a
conditioned air exit portion 391, which is connected to the inlet
portion of the blower 312 via supply duct 326.
[0044] The conditioned air blower system 310 may further include a
condenser unit 392, such as that found in a residential split air
conditioning unit. The condenser unit 392 may include a refrigerant
compressor 393, a refrigerant condenser coil 394 as part of the
closed-loop refrigerant line 390, and heat-rejection fins (not
illustrated) to remove heat from the circulating refrigerant. The
condenser unit 392 may be mounted on a support frame 396 suspended
from the ceiling. The support frame 396 may be positioned well
above the overhead door 370 to provide adequate clearance for the
door's movement.
[0045] In operation, cold refrigerant is pumped through the
evaporator coil 389 within the evaporator unit 387. The centrifugal
blower 312 draws ambient air through the air inlet portion 388,
across the evaporator coil 389 where the air is chilled, through
the supply duct 326, and into the inlet of the centrifugal blower
312. The chilled air is expelled out the elbow conduit 336 and into
the trailer interior 342.
[0046] As the ambient air is drawn across the evaporator coil 389,
the refrigerant in the coil absorbs heat from the air. As the
refrigerant absorbs heat, it evaporates into a low-pressure gas,
which enters the compressor 393. The compressor 393 increases the
pressure and temperature of the refrigerant gas, which then moves
through the condenser coil 394. As the refrigerant passes through
the condenser coil 394, heat is removed and the gas condenses back
into a liquid. The liquid refrigerant flows to an expansion valve
398, which regulates how much refrigerant is supplied to the
evaporator unit 387. The cold refrigerant then flows out the
condenser unit 392 back to the evaporator unit 387, and the cooling
cycle starts over again.
[0047] As used herein, an element or function recited in the
singular and proceeded with the word "a" or "an" should be
understood as not excluding plural said elements or functions,
unless such exclusion is explicitly recited. Furthermore,
references to "one embodiment" should not be interpreted as
excluding the existence of additional embodiments that also
incorporate the recited features.
[0048] While the present invention has been described with
reference to a number of specific embodiments, it will be
understood that the true spirit and scope of the invention should
be determined only with respect to claims that can be supported by
the present specification. Further, while in numerous cases herein
wherein systems and apparatuses and methods are described as having
a certain number of elements it will be understood that such
systems, apparatuses and methods can be practiced with fewer than
the mentioned certain number of elements. Also, while a number of
particular embodiments have been described, it will be understood
that features and aspects that have been described with reference
to each particular embodiment can be used with each remaining
particularly described embodiment.
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